/* Common target dependent code for GDB on ARM systems.
Copyright (C) 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1998, 1999, 2000,
- 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
This file is part of GDB.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
-#include <ctype.h> /* XXX for isupper () */
+#include <ctype.h> /* XXX for isupper (). */
#include "defs.h"
#include "frame.h"
#include "gdbcmd.h"
#include "gdbcore.h"
#include "gdb_string.h"
-#include "dis-asm.h" /* For register styles. */
+#include "dis-asm.h" /* For register styles. */
#include "regcache.h"
+#include "reggroups.h"
#include "doublest.h"
#include "value.h"
#include "arch-utils.h"
#include "prologue-value.h"
#include "target-descriptions.h"
#include "user-regs.h"
+#include "observer.h"
#include "arm-tdep.h"
#include "gdb/sim-arm.h"
#include "elf/arm.h"
#include "gdb_assert.h"
+#include "vec.h"
+
+#include "features/arm-with-m.c"
static int arm_debug;
MSYMBOL_SET_SPECIAL Actually sets the "special" bit.
MSYMBOL_IS_SPECIAL Tests the "special" bit in a minimal symbol. */
-#define MSYMBOL_SET_SPECIAL(msym) \
- MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym)) \
- | 0x80000000)
+#define MSYMBOL_SET_SPECIAL(msym) \
+ MSYMBOL_TARGET_FLAG_1 (msym) = 1
#define MSYMBOL_IS_SPECIAL(msym) \
- (((long) MSYMBOL_INFO (msym) & 0x80000000) != 0)
+ MSYMBOL_TARGET_FLAG_1 (msym)
+
+/* Per-objfile data used for mapping symbols. */
+static const struct objfile_data *arm_objfile_data_key;
+
+struct arm_mapping_symbol
+{
+ bfd_vma value;
+ char type;
+};
+typedef struct arm_mapping_symbol arm_mapping_symbol_s;
+DEF_VEC_O(arm_mapping_symbol_s);
+
+struct arm_per_objfile
+{
+ VEC(arm_mapping_symbol_s) **section_maps;
+};
/* The list of available "set arm ..." and "show arm ..." commands. */
static struct cmd_list_element *setarmcmdlist = NULL;
static enum arm_abi_kind arm_abi_global = ARM_ABI_AUTO;
static const char *arm_abi_string = "auto";
+/* The execution mode to assume. */
+static const char *arm_mode_strings[] =
+ {
+ "auto",
+ "arm",
+ "thumb",
+ NULL
+ };
+
+static const char *arm_fallback_mode_string = "auto";
+static const char *arm_force_mode_string = "auto";
+
/* Number of different reg name sets (options). */
static int num_disassembly_options;
-/* The standard register names, and all the valid aliases for them. */
+/* The standard register names, and all the valid aliases for them. Note
+ that `fp', `sp' and `pc' are not added in this alias list, because they
+ have been added as builtin user registers in
+ std-regs.c:_initialize_frame_reg. */
static const struct
{
const char *name;
{ "tr", 9 },
/* Special names. */
{ "ip", 12 },
- { "sp", 13 },
{ "lr", 14 },
- { "pc", 15 },
/* Names used by GCC (not listed in the ARM EABI). */
{ "sl", 10 },
- { "fp", 11 },
/* A special name from the older ATPCS. */
{ "wr", 7 },
};
static void convert_to_extended (const struct floatformat *, void *,
const void *, int);
+static void arm_neon_quad_read (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int regnum, gdb_byte *buf);
+static void arm_neon_quad_write (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int regnum, const gdb_byte *buf);
+
struct arm_prologue_cache
{
/* The stack pointer at the time this frame was created; i.e. the
struct trad_frame_saved_reg *saved_regs;
};
+static CORE_ADDR arm_analyze_prologue (struct gdbarch *gdbarch,
+ CORE_ADDR prologue_start,
+ CORE_ADDR prologue_end,
+ struct arm_prologue_cache *cache);
+
+/* Architecture version for displaced stepping. This effects the behaviour of
+ certain instructions, and really should not be hard-wired. */
+
+#define DISPLACED_STEPPING_ARCH_VERSION 5
+
/* Addresses for calling Thumb functions have the bit 0 set.
Here are some macros to test, set, or clear bit 0 of addresses. */
#define IS_THUMB_ADDR(addr) ((addr) & 1)
int arm_apcs_32 = 1;
+/* Return the bit mask in ARM_PS_REGNUM that indicates Thumb mode. */
+
+int
+arm_psr_thumb_bit (struct gdbarch *gdbarch)
+{
+ if (gdbarch_tdep (gdbarch)->is_m)
+ return XPSR_T;
+ else
+ return CPSR_T;
+}
+
+/* Determine if FRAME is executing in Thumb mode. */
+
+int
+arm_frame_is_thumb (struct frame_info *frame)
+{
+ CORE_ADDR cpsr;
+ ULONGEST t_bit = arm_psr_thumb_bit (get_frame_arch (frame));
+
+ /* Every ARM frame unwinder can unwind the T bit of the CPSR, either
+ directly (from a signal frame or dummy frame) or by interpreting
+ the saved LR (from a prologue or DWARF frame). So consult it and
+ trust the unwinders. */
+ cpsr = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
+
+ return (cpsr & t_bit) != 0;
+}
+
+/* Callback for VEC_lower_bound. */
+
+static inline int
+arm_compare_mapping_symbols (const struct arm_mapping_symbol *lhs,
+ const struct arm_mapping_symbol *rhs)
+{
+ return lhs->value < rhs->value;
+}
+
+/* Search for the mapping symbol covering MEMADDR. If one is found,
+ return its type. Otherwise, return 0. If START is non-NULL,
+ set *START to the location of the mapping symbol. */
+
+static char
+arm_find_mapping_symbol (CORE_ADDR memaddr, CORE_ADDR *start)
+{
+ struct obj_section *sec;
+
+ /* If there are mapping symbols, consult them. */
+ sec = find_pc_section (memaddr);
+ if (sec != NULL)
+ {
+ struct arm_per_objfile *data;
+ VEC(arm_mapping_symbol_s) *map;
+ struct arm_mapping_symbol map_key = { memaddr - obj_section_addr (sec),
+ 0 };
+ unsigned int idx;
+
+ data = objfile_data (sec->objfile, arm_objfile_data_key);
+ if (data != NULL)
+ {
+ map = data->section_maps[sec->the_bfd_section->index];
+ if (!VEC_empty (arm_mapping_symbol_s, map))
+ {
+ struct arm_mapping_symbol *map_sym;
+
+ idx = VEC_lower_bound (arm_mapping_symbol_s, map, &map_key,
+ arm_compare_mapping_symbols);
+
+ /* VEC_lower_bound finds the earliest ordered insertion
+ point. If the following symbol starts at this exact
+ address, we use that; otherwise, the preceding
+ mapping symbol covers this address. */
+ if (idx < VEC_length (arm_mapping_symbol_s, map))
+ {
+ map_sym = VEC_index (arm_mapping_symbol_s, map, idx);
+ if (map_sym->value == map_key.value)
+ {
+ if (start)
+ *start = map_sym->value + obj_section_addr (sec);
+ return map_sym->type;
+ }
+ }
+
+ if (idx > 0)
+ {
+ map_sym = VEC_index (arm_mapping_symbol_s, map, idx - 1);
+ if (start)
+ *start = map_sym->value + obj_section_addr (sec);
+ return map_sym->type;
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+static CORE_ADDR arm_get_next_pc_raw (struct frame_info *frame,
+ CORE_ADDR pc, int insert_bkpt);
+
/* Determine if the program counter specified in MEMADDR is in a Thumb
- function. */
+ function. This function should be called for addresses unrelated to
+ any executing frame; otherwise, prefer arm_frame_is_thumb. */
-static int
-arm_pc_is_thumb (CORE_ADDR memaddr)
+int
+arm_pc_is_thumb (struct gdbarch *gdbarch, CORE_ADDR memaddr)
{
+ struct obj_section *sec;
struct minimal_symbol *sym;
+ char type;
+ struct displaced_step_closure* dsc
+ = get_displaced_step_closure_by_addr(memaddr);
+
+ /* If checking the mode of displaced instruction in copy area, the mode
+ should be determined by instruction on the original address. */
+ if (dsc)
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: check mode of %.8lx instead of %.8lx\n",
+ (unsigned long) dsc->insn_addr,
+ (unsigned long) memaddr);
+ memaddr = dsc->insn_addr;
+ }
/* If bit 0 of the address is set, assume this is a Thumb address. */
if (IS_THUMB_ADDR (memaddr))
return 1;
+ /* If the user wants to override the symbol table, let him. */
+ if (strcmp (arm_force_mode_string, "arm") == 0)
+ return 0;
+ if (strcmp (arm_force_mode_string, "thumb") == 0)
+ return 1;
+
+ /* ARM v6-M and v7-M are always in Thumb mode. */
+ if (gdbarch_tdep (gdbarch)->is_m)
+ return 1;
+
+ /* If there are mapping symbols, consult them. */
+ type = arm_find_mapping_symbol (memaddr, NULL);
+ if (type)
+ return type == 't';
+
/* Thumb functions have a "special" bit set in minimal symbols. */
sym = lookup_minimal_symbol_by_pc (memaddr);
if (sym)
+ return (MSYMBOL_IS_SPECIAL (sym));
+
+ /* If the user wants to override the fallback mode, let them. */
+ if (strcmp (arm_fallback_mode_string, "arm") == 0)
+ return 0;
+ if (strcmp (arm_fallback_mode_string, "thumb") == 0)
+ return 1;
+
+ /* If we couldn't find any symbol, but we're talking to a running
+ target, then trust the current value of $cpsr. This lets
+ "display/i $pc" always show the correct mode (though if there is
+ a symbol table we will not reach here, so it still may not be
+ displayed in the mode it will be executed).
+
+ As a further heuristic if we detect that we are doing a single-step we
+ see what state executing the current instruction ends up with us being
+ in. */
+ if (target_has_registers)
{
- return (MSYMBOL_IS_SPECIAL (sym));
- }
- else
- {
- return 0;
+ struct frame_info *current_frame = get_current_frame ();
+ CORE_ADDR current_pc = get_frame_pc (current_frame);
+ int is_thumb = arm_frame_is_thumb (current_frame);
+ CORE_ADDR next_pc;
+ if (memaddr == current_pc)
+ return is_thumb;
+ else
+ {
+ struct gdbarch *gdbarch = get_frame_arch (current_frame);
+ next_pc = arm_get_next_pc_raw (current_frame, current_pc, FALSE);
+ if (memaddr == gdbarch_addr_bits_remove (gdbarch, next_pc))
+ return IS_THUMB_ADDR (next_pc);
+ else
+ return is_thumb;
+ }
}
+
+ /* Otherwise we're out of luck; we assume ARM. */
+ return 0;
}
/* Remove useless bits from addresses in a running program. */
static CORE_ADDR
-arm_addr_bits_remove (CORE_ADDR val)
+arm_addr_bits_remove (struct gdbarch *gdbarch, CORE_ADDR val)
{
if (arm_apcs_32)
return UNMAKE_THUMB_ADDR (val);
/* When reading symbols, we need to zap the low bit of the address,
which may be set to 1 for Thumb functions. */
static CORE_ADDR
-arm_smash_text_address (CORE_ADDR val)
+arm_smash_text_address (struct gdbarch *gdbarch, CORE_ADDR val)
{
return val & ~1;
}
+/* Return 1 if PC is the start of a compiler helper function which
+ can be safely ignored during prologue skipping. IS_THUMB is true
+ if the function is known to be a Thumb function due to the way it
+ is being called. */
+static int
+skip_prologue_function (struct gdbarch *gdbarch, CORE_ADDR pc, int is_thumb)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ struct minimal_symbol *msym;
+
+ msym = lookup_minimal_symbol_by_pc (pc);
+ if (msym != NULL
+ && SYMBOL_VALUE_ADDRESS (msym) == pc
+ && SYMBOL_LINKAGE_NAME (msym) != NULL)
+ {
+ const char *name = SYMBOL_LINKAGE_NAME (msym);
+
+ /* The GNU linker's Thumb call stub to foo is named
+ __foo_from_thumb. */
+ if (strstr (name, "_from_thumb") != NULL)
+ name += 2;
+
+ /* On soft-float targets, __truncdfsf2 is called to convert promoted
+ arguments to their argument types in non-prototyped
+ functions. */
+ if (strncmp (name, "__truncdfsf2", strlen ("__truncdfsf2")) == 0)
+ return 1;
+ if (strncmp (name, "__aeabi_d2f", strlen ("__aeabi_d2f")) == 0)
+ return 1;
+
+ /* Internal functions related to thread-local storage. */
+ if (strncmp (name, "__tls_get_addr", strlen ("__tls_get_addr")) == 0)
+ return 1;
+ if (strncmp (name, "__aeabi_read_tp", strlen ("__aeabi_read_tp")) == 0)
+ return 1;
+ }
+ else
+ {
+ /* If we run against a stripped glibc, we may be unable to identify
+ special functions by name. Check for one important case,
+ __aeabi_read_tp, by comparing the *code* against the default
+ implementation (this is hand-written ARM assembler in glibc). */
+
+ if (!is_thumb
+ && read_memory_unsigned_integer (pc, 4, byte_order_for_code)
+ == 0xe3e00a0f /* mov r0, #0xffff0fff */
+ && read_memory_unsigned_integer (pc + 4, 4, byte_order_for_code)
+ == 0xe240f01f) /* sub pc, r0, #31 */
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Support routines for instruction parsing. */
+#define submask(x) ((1L << ((x) + 1)) - 1)
+#define bit(obj,st) (((obj) >> (st)) & 1)
+#define bits(obj,st,fn) (((obj) >> (st)) & submask ((fn) - (st)))
+#define sbits(obj,st,fn) \
+ ((long) (bits(obj,st,fn) | ((long) bit(obj,fn) * ~ submask (fn - st))))
+#define BranchDest(addr,instr) \
+ ((CORE_ADDR) (((long) (addr)) + 8 + (sbits (instr, 0, 23) << 2)))
+
+/* Extract the immediate from instruction movw/movt of encoding T. INSN1 is
+ the first 16-bit of instruction, and INSN2 is the second 16-bit of
+ instruction. */
+#define EXTRACT_MOVW_MOVT_IMM_T(insn1, insn2) \
+ ((bits ((insn1), 0, 3) << 12) \
+ | (bits ((insn1), 10, 10) << 11) \
+ | (bits ((insn2), 12, 14) << 8) \
+ | bits ((insn2), 0, 7))
+
+/* Extract the immediate from instruction movw/movt of encoding A. INSN is
+ the 32-bit instruction. */
+#define EXTRACT_MOVW_MOVT_IMM_A(insn) \
+ ((bits ((insn), 16, 19) << 12) \
+ | bits ((insn), 0, 11))
+
+/* Decode immediate value; implements ThumbExpandImmediate pseudo-op. */
+
+static unsigned int
+thumb_expand_immediate (unsigned int imm)
+{
+ unsigned int count = imm >> 7;
+
+ if (count < 8)
+ switch (count / 2)
+ {
+ case 0:
+ return imm & 0xff;
+ case 1:
+ return (imm & 0xff) | ((imm & 0xff) << 16);
+ case 2:
+ return ((imm & 0xff) << 8) | ((imm & 0xff) << 24);
+ case 3:
+ return (imm & 0xff) | ((imm & 0xff) << 8)
+ | ((imm & 0xff) << 16) | ((imm & 0xff) << 24);
+ }
+
+ return (0x80 | (imm & 0x7f)) << (32 - count);
+}
+
+/* Return 1 if the 16-bit Thumb instruction INST might change
+ control flow, 0 otherwise. */
+
+static int
+thumb_instruction_changes_pc (unsigned short inst)
+{
+ if ((inst & 0xff00) == 0xbd00) /* pop {rlist, pc} */
+ return 1;
+
+ if ((inst & 0xf000) == 0xd000) /* conditional branch */
+ return 1;
+
+ if ((inst & 0xf800) == 0xe000) /* unconditional branch */
+ return 1;
+
+ if ((inst & 0xff00) == 0x4700) /* bx REG, blx REG */
+ return 1;
+
+ if ((inst & 0xff87) == 0x4687) /* mov pc, REG */
+ return 1;
+
+ if ((inst & 0xf500) == 0xb100) /* CBNZ or CBZ. */
+ return 1;
+
+ return 0;
+}
+
+/* Return 1 if the 32-bit Thumb instruction in INST1 and INST2
+ might change control flow, 0 otherwise. */
+
+static int
+thumb2_instruction_changes_pc (unsigned short inst1, unsigned short inst2)
+{
+ if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000)
+ {
+ /* Branches and miscellaneous control instructions. */
+
+ if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000)
+ {
+ /* B, BL, BLX. */
+ return 1;
+ }
+ else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00)
+ {
+ /* SUBS PC, LR, #imm8. */
+ return 1;
+ }
+ else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380)
+ {
+ /* Conditional branch. */
+ return 1;
+ }
+
+ return 0;
+ }
+
+ if ((inst1 & 0xfe50) == 0xe810)
+ {
+ /* Load multiple or RFE. */
+
+ if (bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* LDMIA or POP */
+ if (bit (inst2, 15))
+ return 1;
+ }
+ else if (!bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* LDMDB */
+ if (bit (inst2, 15))
+ return 1;
+ }
+ else if (bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* RFEIA */
+ return 1;
+ }
+ else if (!bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* RFEDB */
+ return 1;
+ }
+
+ return 0;
+ }
+
+ if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00)
+ {
+ /* MOV PC or MOVS PC. */
+ return 1;
+ }
+
+ if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000)
+ {
+ /* LDR PC. */
+ if (bits (inst1, 0, 3) == 15)
+ return 1;
+ if (bit (inst1, 7))
+ return 1;
+ if (bit (inst2, 11))
+ return 1;
+ if ((inst2 & 0x0fc0) == 0x0000)
+ return 1;
+
+ return 0;
+ }
+
+ if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
+ {
+ /* TBB. */
+ return 1;
+ }
+
+ if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010)
+ {
+ /* TBH. */
+ return 1;
+ }
+
+ return 0;
+}
+
/* Analyze a Thumb prologue, looking for a recognizable stack frame
and frame pointer. Scan until we encounter a store that could
- clobber the stack frame unexpectedly, or an unknown instruction. */
+ clobber the stack frame unexpectedly, or an unknown instruction.
+ Return the last address which is definitely safe to skip for an
+ initial breakpoint. */
static CORE_ADDR
thumb_analyze_prologue (struct gdbarch *gdbarch,
CORE_ADDR start, CORE_ADDR limit,
struct arm_prologue_cache *cache)
{
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
int i;
pv_t regs[16];
struct pv_area *stack;
struct cleanup *back_to;
CORE_ADDR offset;
+ CORE_ADDR unrecognized_pc = 0;
for (i = 0; i < 16; i++)
regs[i] = pv_register (i, 0);
- stack = make_pv_area (ARM_SP_REGNUM);
+ stack = make_pv_area (ARM_SP_REGNUM, gdbarch_addr_bit (gdbarch));
back_to = make_cleanup_free_pv_area (stack);
- /* The call instruction saved PC in LR, and the current PC is not
- interesting. Due to this file's conventions, we want the value
- of LR at this function's entry, not at the call site, so we do
- not record the save of the PC - when the ARM prologue analyzer
- has also been converted to the pv mechanism, we could record the
- save here and remove the hack in prev_register. */
- regs[ARM_PC_REGNUM] = pv_unknown ();
-
while (start < limit)
{
unsigned short insn;
- insn = read_memory_unsigned_integer (start, 2);
+ insn = read_memory_unsigned_integer (start, 2, byte_order_for_code);
if ((insn & 0xfe00) == 0xb400) /* push { rlist } */
{
regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM],
offset);
}
- else if ((insn & 0xff00) == 0xaf00) /* add r7, sp, #imm */
- regs[THUMB_FP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM],
- (insn & 0xff) << 2);
+ else if ((insn & 0xf800) == 0xa800) /* add Rd, sp, #imm */
+ regs[bits (insn, 8, 10)] = pv_add_constant (regs[ARM_SP_REGNUM],
+ (insn & 0xff) << 2);
+ else if ((insn & 0xfe00) == 0x1c00 /* add Rd, Rn, #imm */
+ && pv_is_register (regs[bits (insn, 3, 5)], ARM_SP_REGNUM))
+ regs[bits (insn, 0, 2)] = pv_add_constant (regs[bits (insn, 3, 5)],
+ bits (insn, 6, 8));
+ else if ((insn & 0xf800) == 0x3000 /* add Rd, #imm */
+ && pv_is_register (regs[bits (insn, 8, 10)], ARM_SP_REGNUM))
+ regs[bits (insn, 8, 10)] = pv_add_constant (regs[bits (insn, 8, 10)],
+ bits (insn, 0, 7));
+ else if ((insn & 0xfe00) == 0x1800 /* add Rd, Rn, Rm */
+ && pv_is_register (regs[bits (insn, 6, 8)], ARM_SP_REGNUM)
+ && pv_is_constant (regs[bits (insn, 3, 5)]))
+ regs[bits (insn, 0, 2)] = pv_add (regs[bits (insn, 3, 5)],
+ regs[bits (insn, 6, 8)]);
+ else if ((insn & 0xff00) == 0x4400 /* add Rd, Rm */
+ && pv_is_constant (regs[bits (insn, 3, 6)]))
+ {
+ int rd = (bit (insn, 7) << 3) + bits (insn, 0, 2);
+ int rm = bits (insn, 3, 6);
+ regs[rd] = pv_add (regs[rd], regs[rm]);
+ }
else if ((insn & 0xff00) == 0x4600) /* mov hi, lo or mov lo, hi */
{
int dst_reg = (insn & 0x7) + ((insn & 0x80) >> 4);
pv_area_store (stack, addr, 4, regs[regno]);
}
- else
+ else if ((insn & 0xf800) == 0x6000) /* str rd, [rn, #off] */
{
- /* We don't know what this instruction is. We're finished
- scanning. NOTE: Recognizing more safe-to-ignore
- instructions here will improve support for optimized
- code. */
- break;
- }
+ int rd = bits (insn, 0, 2);
+ int rn = bits (insn, 3, 5);
+ pv_t addr;
- start += 2;
- }
+ offset = bits (insn, 6, 10) << 2;
+ addr = pv_add_constant (regs[rn], offset);
- if (cache == NULL)
- {
- do_cleanups (back_to);
- return start;
- }
+ if (pv_area_store_would_trash (stack, addr))
+ break;
- if (pv_is_register (regs[ARM_FP_REGNUM], ARM_SP_REGNUM))
- {
- /* Frame pointer is fp. Frame size is constant. */
- cache->framereg = ARM_FP_REGNUM;
- cache->framesize = -regs[ARM_FP_REGNUM].k;
- }
- else if (pv_is_register (regs[THUMB_FP_REGNUM], ARM_SP_REGNUM))
- {
- /* Frame pointer is r7. Frame size is constant. */
- cache->framereg = THUMB_FP_REGNUM;
- cache->framesize = -regs[THUMB_FP_REGNUM].k;
- }
- else if (pv_is_register (regs[ARM_SP_REGNUM], ARM_SP_REGNUM))
- {
- /* Try the stack pointer... this is a bit desperate. */
- cache->framereg = ARM_SP_REGNUM;
- cache->framesize = -regs[ARM_SP_REGNUM].k;
- }
- else
- {
- /* We're just out of luck. We don't know where the frame is. */
- cache->framereg = -1;
- cache->framesize = 0;
- }
+ pv_area_store (stack, addr, 4, regs[rd]);
+ }
+ else if (((insn & 0xf800) == 0x7000 /* strb Rd, [Rn, #off] */
+ || (insn & 0xf800) == 0x8000) /* strh Rd, [Rn, #off] */
+ && pv_is_register (regs[bits (insn, 3, 5)], ARM_SP_REGNUM))
+ /* Ignore stores of argument registers to the stack. */
+ ;
+ else if ((insn & 0xf800) == 0xc800 /* ldmia Rn!, { registers } */
+ && pv_is_register (regs[bits (insn, 8, 10)], ARM_SP_REGNUM))
+ /* Ignore block loads from the stack, potentially copying
+ parameters from memory. */
+ ;
+ else if ((insn & 0xf800) == 0x9800 /* ldr Rd, [Rn, #immed] */
+ || ((insn & 0xf800) == 0x6800 /* ldr Rd, [sp, #immed] */
+ && pv_is_register (regs[bits (insn, 3, 5)], ARM_SP_REGNUM)))
+ /* Similarly ignore single loads from the stack. */
+ ;
+ else if ((insn & 0xffc0) == 0x0000 /* lsls Rd, Rm, #0 */
+ || (insn & 0xffc0) == 0x1c00) /* add Rd, Rn, #0 */
+ /* Skip register copies, i.e. saves to another register
+ instead of the stack. */
+ ;
+ else if ((insn & 0xf800) == 0x2000) /* movs Rd, #imm */
+ /* Recognize constant loads; even with small stacks these are necessary
+ on Thumb. */
+ regs[bits (insn, 8, 10)] = pv_constant (bits (insn, 0, 7));
+ else if ((insn & 0xf800) == 0x4800) /* ldr Rd, [pc, #imm] */
+ {
+ /* Constant pool loads, for the same reason. */
+ unsigned int constant;
+ CORE_ADDR loc;
- for (i = 0; i < 16; i++)
- if (pv_area_find_reg (stack, gdbarch, i, &offset))
- cache->saved_regs[i].addr = offset;
+ loc = start + 4 + bits (insn, 0, 7) * 4;
+ constant = read_memory_unsigned_integer (loc, 4, byte_order);
+ regs[bits (insn, 8, 10)] = pv_constant (constant);
+ }
+ else if ((insn & 0xe000) == 0xe000)
+ {
+ unsigned short inst2;
- do_cleanups (back_to);
- return start;
-}
+ inst2 = read_memory_unsigned_integer (start + 2, 2,
+ byte_order_for_code);
-/* Advance the PC across any function entry prologue instructions to
- reach some "real" code.
+ if ((insn & 0xf800) == 0xf000 && (inst2 & 0xe800) == 0xe800)
+ {
+ /* BL, BLX. Allow some special function calls when
+ skipping the prologue; GCC generates these before
+ storing arguments to the stack. */
+ CORE_ADDR nextpc;
+ int j1, j2, imm1, imm2;
+
+ imm1 = sbits (insn, 0, 10);
+ imm2 = bits (inst2, 0, 10);
+ j1 = bit (inst2, 13);
+ j2 = bit (inst2, 11);
+
+ offset = ((imm1 << 12) + (imm2 << 1));
+ offset ^= ((!j2) << 22) | ((!j1) << 23);
+
+ nextpc = start + 4 + offset;
+ /* For BLX make sure to clear the low bits. */
+ if (bit (inst2, 12) == 0)
+ nextpc = nextpc & 0xfffffffc;
+
+ if (!skip_prologue_function (gdbarch, nextpc,
+ bit (inst2, 12) != 0))
+ break;
+ }
- The APCS (ARM Procedure Call Standard) defines the following
- prologue:
+ else if ((insn & 0xffd0) == 0xe900 /* stmdb Rn{!},
+ { registers } */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ pv_t addr = regs[bits (insn, 0, 3)];
+ int regno;
- mov ip, sp
- [stmfd sp!, {a1,a2,a3,a4}]
- stmfd sp!, {...,fp,ip,lr,pc}
- [stfe f7, [sp, #-12]!]
- [stfe f6, [sp, #-12]!]
- [stfe f5, [sp, #-12]!]
- [stfe f4, [sp, #-12]!]
- sub fp, ip, #nn @@ nn == 20 or 4 depending on second insn */
+ if (pv_area_store_would_trash (stack, addr))
+ break;
-static CORE_ADDR
-arm_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
-{
- unsigned long inst;
- CORE_ADDR skip_pc;
- CORE_ADDR func_addr, func_end = 0;
- char *func_name;
- struct symtab_and_line sal;
+ /* Calculate offsets of saved registers. */
+ for (regno = ARM_LR_REGNUM; regno >= 0; regno--)
+ if (inst2 & (1 << regno))
+ {
+ addr = pv_add_constant (addr, -4);
+ pv_area_store (stack, addr, 4, regs[regno]);
+ }
- /* If we're in a dummy frame, don't even try to skip the prologue. */
- if (deprecated_pc_in_call_dummy (pc))
- return pc;
+ if (insn & 0x0020)
+ regs[bits (insn, 0, 3)] = addr;
+ }
- /* See what the symbol table says. */
+ else if ((insn & 0xff50) == 0xe940 /* strd Rt, Rt2,
+ [Rn, #+/-imm]{!} */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ int regno1 = bits (inst2, 12, 15);
+ int regno2 = bits (inst2, 8, 11);
+ pv_t addr = regs[bits (insn, 0, 3)];
- if (find_pc_partial_function (pc, &func_name, &func_addr, &func_end))
- {
- struct symbol *sym;
+ offset = inst2 & 0xff;
+ if (insn & 0x0080)
+ addr = pv_add_constant (addr, offset);
+ else
+ addr = pv_add_constant (addr, -offset);
- /* Found a function. */
- sym = lookup_symbol (func_name, NULL, VAR_DOMAIN, NULL, NULL);
- if (sym && SYMBOL_LANGUAGE (sym) != language_asm)
- {
- /* Don't use this trick for assembly source files. */
- sal = find_pc_line (func_addr, 0);
- if ((sal.line != 0) && (sal.end < func_end))
- return sal.end;
- }
- }
+ if (pv_area_store_would_trash (stack, addr))
+ break;
- /* Can't find the prologue end in the symbol table, try it the hard way
- by disassembling the instructions. */
+ pv_area_store (stack, addr, 4, regs[regno1]);
+ pv_area_store (stack, pv_add_constant (addr, 4),
+ 4, regs[regno2]);
+
+ if (insn & 0x0020)
+ regs[bits (insn, 0, 3)] = addr;
+ }
+
+ else if ((insn & 0xfff0) == 0xf8c0 /* str Rt,[Rn,+/-#imm]{!} */
+ && (inst2 & 0x0c00) == 0x0c00
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ int regno = bits (inst2, 12, 15);
+ pv_t addr = regs[bits (insn, 0, 3)];
+
+ offset = inst2 & 0xff;
+ if (inst2 & 0x0200)
+ addr = pv_add_constant (addr, offset);
+ else
+ addr = pv_add_constant (addr, -offset);
+
+ if (pv_area_store_would_trash (stack, addr))
+ break;
+
+ pv_area_store (stack, addr, 4, regs[regno]);
+
+ if (inst2 & 0x0100)
+ regs[bits (insn, 0, 3)] = addr;
+ }
+
+ else if ((insn & 0xfff0) == 0xf8c0 /* str.w Rt,[Rn,#imm] */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ {
+ int regno = bits (inst2, 12, 15);
+ pv_t addr;
+
+ offset = inst2 & 0xfff;
+ addr = pv_add_constant (regs[bits (insn, 0, 3)], offset);
+
+ if (pv_area_store_would_trash (stack, addr))
+ break;
+
+ pv_area_store (stack, addr, 4, regs[regno]);
+ }
+
+ else if ((insn & 0xffd0) == 0xf880 /* str{bh}.w Rt,[Rn,#imm] */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Ignore stores of argument registers to the stack. */
+ ;
+
+ else if ((insn & 0xffd0) == 0xf800 /* str{bh} Rt,[Rn,#+/-imm] */
+ && (inst2 & 0x0d00) == 0x0c00
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Ignore stores of argument registers to the stack. */
+ ;
+
+ else if ((insn & 0xffd0) == 0xe890 /* ldmia Rn[!],
+ { registers } */
+ && (inst2 & 0x8000) == 0x0000
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Ignore block loads from the stack, potentially copying
+ parameters from memory. */
+ ;
+
+ else if ((insn & 0xffb0) == 0xe950 /* ldrd Rt, Rt2,
+ [Rn, #+/-imm] */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Similarly ignore dual loads from the stack. */
+ ;
+
+ else if ((insn & 0xfff0) == 0xf850 /* ldr Rt,[Rn,#+/-imm] */
+ && (inst2 & 0x0d00) == 0x0c00
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Similarly ignore single loads from the stack. */
+ ;
+
+ else if ((insn & 0xfff0) == 0xf8d0 /* ldr.w Rt,[Rn,#imm] */
+ && pv_is_register (regs[bits (insn, 0, 3)], ARM_SP_REGNUM))
+ /* Similarly ignore single loads from the stack. */
+ ;
+
+ else if ((insn & 0xfbf0) == 0xf100 /* add.w Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)],
+ thumb_expand_immediate (imm));
+ }
+
+ else if ((insn & 0xfbf0) == 0xf200 /* addw Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)], imm);
+ }
+
+ else if ((insn & 0xfbf0) == 0xf1a0 /* sub.w Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)],
+ - (CORE_ADDR) thumb_expand_immediate (imm));
+ }
+
+ else if ((insn & 0xfbf0) == 0xf2a0 /* subw Rd, Rn, #imm */
+ && (inst2 & 0x8000) == 0x0000)
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_add_constant (regs[bits (insn, 0, 3)], - (CORE_ADDR) imm);
+ }
+
+ else if ((insn & 0xfbff) == 0xf04f) /* mov.w Rd, #const */
+ {
+ unsigned int imm = ((bits (insn, 10, 10) << 11)
+ | (bits (inst2, 12, 14) << 8)
+ | bits (inst2, 0, 7));
+
+ regs[bits (inst2, 8, 11)]
+ = pv_constant (thumb_expand_immediate (imm));
+ }
+
+ else if ((insn & 0xfbf0) == 0xf240) /* movw Rd, #const */
+ {
+ unsigned int imm
+ = EXTRACT_MOVW_MOVT_IMM_T (insn, inst2);
+
+ regs[bits (inst2, 8, 11)] = pv_constant (imm);
+ }
+
+ else if (insn == 0xea5f /* mov.w Rd,Rm */
+ && (inst2 & 0xf0f0) == 0)
+ {
+ int dst_reg = (inst2 & 0x0f00) >> 8;
+ int src_reg = inst2 & 0xf;
+ regs[dst_reg] = regs[src_reg];
+ }
+
+ else if ((insn & 0xff7f) == 0xf85f) /* ldr.w Rt,<label> */
+ {
+ /* Constant pool loads. */
+ unsigned int constant;
+ CORE_ADDR loc;
+
+ offset = bits (insn, 0, 11);
+ if (insn & 0x0080)
+ loc = start + 4 + offset;
+ else
+ loc = start + 4 - offset;
+
+ constant = read_memory_unsigned_integer (loc, 4, byte_order);
+ regs[bits (inst2, 12, 15)] = pv_constant (constant);
+ }
+
+ else if ((insn & 0xff7f) == 0xe95f) /* ldrd Rt,Rt2,<label> */
+ {
+ /* Constant pool loads. */
+ unsigned int constant;
+ CORE_ADDR loc;
+
+ offset = bits (insn, 0, 7) << 2;
+ if (insn & 0x0080)
+ loc = start + 4 + offset;
+ else
+ loc = start + 4 - offset;
+
+ constant = read_memory_unsigned_integer (loc, 4, byte_order);
+ regs[bits (inst2, 12, 15)] = pv_constant (constant);
+
+ constant = read_memory_unsigned_integer (loc + 4, 4, byte_order);
+ regs[bits (inst2, 8, 11)] = pv_constant (constant);
+ }
+
+ else if (thumb2_instruction_changes_pc (insn, inst2))
+ {
+ /* Don't scan past anything that might change control flow. */
+ break;
+ }
+ else
+ {
+ /* The optimizer might shove anything into the prologue,
+ so we just skip what we don't recognize. */
+ unrecognized_pc = start;
+ }
+
+ start += 2;
+ }
+ else if (thumb_instruction_changes_pc (insn))
+ {
+ /* Don't scan past anything that might change control flow. */
+ break;
+ }
+ else
+ {
+ /* The optimizer might shove anything into the prologue,
+ so we just skip what we don't recognize. */
+ unrecognized_pc = start;
+ }
+
+ start += 2;
+ }
+
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "Prologue scan stopped at %s\n",
+ paddress (gdbarch, start));
+
+ if (unrecognized_pc == 0)
+ unrecognized_pc = start;
+
+ if (cache == NULL)
+ {
+ do_cleanups (back_to);
+ return unrecognized_pc;
+ }
+
+ if (pv_is_register (regs[ARM_FP_REGNUM], ARM_SP_REGNUM))
+ {
+ /* Frame pointer is fp. Frame size is constant. */
+ cache->framereg = ARM_FP_REGNUM;
+ cache->framesize = -regs[ARM_FP_REGNUM].k;
+ }
+ else if (pv_is_register (regs[THUMB_FP_REGNUM], ARM_SP_REGNUM))
+ {
+ /* Frame pointer is r7. Frame size is constant. */
+ cache->framereg = THUMB_FP_REGNUM;
+ cache->framesize = -regs[THUMB_FP_REGNUM].k;
+ }
+ else if (pv_is_register (regs[ARM_SP_REGNUM], ARM_SP_REGNUM))
+ {
+ /* Try the stack pointer... this is a bit desperate. */
+ cache->framereg = ARM_SP_REGNUM;
+ cache->framesize = -regs[ARM_SP_REGNUM].k;
+ }
+ else
+ {
+ /* We're just out of luck. We don't know where the frame is. */
+ cache->framereg = -1;
+ cache->framesize = 0;
+ }
+
+ for (i = 0; i < 16; i++)
+ if (pv_area_find_reg (stack, gdbarch, i, &offset))
+ cache->saved_regs[i].addr = offset;
+
+ do_cleanups (back_to);
+ return unrecognized_pc;
+}
+
+
+/* Try to analyze the instructions starting from PC, which load symbol
+ __stack_chk_guard. Return the address of instruction after loading this
+ symbol, set the dest register number to *BASEREG, and set the size of
+ instructions for loading symbol in OFFSET. Return 0 if instructions are
+ not recognized. */
+
+static CORE_ADDR
+arm_analyze_load_stack_chk_guard(CORE_ADDR pc, struct gdbarch *gdbarch,
+ unsigned int *destreg, int *offset)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ int is_thumb = arm_pc_is_thumb (gdbarch, pc);
+ unsigned int low, high, address;
+
+ address = 0;
+ if (is_thumb)
+ {
+ unsigned short insn1
+ = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
+
+ if ((insn1 & 0xf800) == 0x4800) /* ldr Rd, #immed */
+ {
+ *destreg = bits (insn1, 8, 10);
+ *offset = 2;
+ address = bits (insn1, 0, 7);
+ }
+ else if ((insn1 & 0xfbf0) == 0xf240) /* movw Rd, #const */
+ {
+ unsigned short insn2
+ = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code);
+
+ low = EXTRACT_MOVW_MOVT_IMM_T (insn1, insn2);
+
+ insn1
+ = read_memory_unsigned_integer (pc + 4, 2, byte_order_for_code);
+ insn2
+ = read_memory_unsigned_integer (pc + 6, 2, byte_order_for_code);
+
+ /* movt Rd, #const */
+ if ((insn1 & 0xfbc0) == 0xf2c0)
+ {
+ high = EXTRACT_MOVW_MOVT_IMM_T (insn1, insn2);
+ *destreg = bits (insn2, 8, 11);
+ *offset = 8;
+ address = (high << 16 | low);
+ }
+ }
+ }
+ else
+ {
+ unsigned int insn
+ = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+
+ if ((insn & 0x0e5f0000) == 0x041f0000) /* ldr Rd, #immed */
+ {
+ address = bits (insn, 0, 11);
+ *destreg = bits (insn, 12, 15);
+ *offset = 4;
+ }
+ else if ((insn & 0x0ff00000) == 0x03000000) /* movw Rd, #const */
+ {
+ low = EXTRACT_MOVW_MOVT_IMM_A (insn);
+
+ insn
+ = read_memory_unsigned_integer (pc + 4, 4, byte_order_for_code);
+
+ if ((insn & 0x0ff00000) == 0x03400000) /* movt Rd, #const */
+ {
+ high = EXTRACT_MOVW_MOVT_IMM_A (insn);
+ *destreg = bits (insn, 12, 15);
+ *offset = 8;
+ address = (high << 16 | low);
+ }
+ }
+ }
+
+ return address;
+}
+
+/* Try to skip a sequence of instructions used for stack protector. If PC
+ points to the first instruction of this sequence, return the address of
+ first instruction after this sequence, otherwise, return original PC.
+
+ On arm, this sequence of instructions is composed of mainly three steps,
+ Step 1: load symbol __stack_chk_guard,
+ Step 2: load from address of __stack_chk_guard,
+ Step 3: store it to somewhere else.
+
+ Usually, instructions on step 2 and step 3 are the same on various ARM
+ architectures. On step 2, it is one instruction 'ldr Rx, [Rn, #0]', and
+ on step 3, it is also one instruction 'str Rx, [r7, #immd]'. However,
+ instructions in step 1 vary from different ARM architectures. On ARMv7,
+ they are,
+
+ movw Rn, #:lower16:__stack_chk_guard
+ movt Rn, #:upper16:__stack_chk_guard
+
+ On ARMv5t, it is,
+
+ ldr Rn, .Label
+ ....
+ .Lable:
+ .word __stack_chk_guard
+
+ Since ldr/str is a very popular instruction, we can't use them as
+ 'fingerprint' or 'signature' of stack protector sequence. Here we choose
+ sequence {movw/movt, ldr}/ldr/str plus symbol __stack_chk_guard, if not
+ stripped, as the 'fingerprint' of a stack protector cdoe sequence. */
+
+static CORE_ADDR
+arm_skip_stack_protector(CORE_ADDR pc, struct gdbarch *gdbarch)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned int address, basereg;
+ struct minimal_symbol *stack_chk_guard;
+ int offset;
+ int is_thumb = arm_pc_is_thumb (gdbarch, pc);
+ CORE_ADDR addr;
+
+ /* Try to parse the instructions in Step 1. */
+ addr = arm_analyze_load_stack_chk_guard (pc, gdbarch,
+ &basereg, &offset);
+ if (!addr)
+ return pc;
+
+ stack_chk_guard = lookup_minimal_symbol_by_pc (addr);
+ /* If name of symbol doesn't start with '__stack_chk_guard', this
+ instruction sequence is not for stack protector. If symbol is
+ removed, we conservatively think this sequence is for stack protector. */
+ if (stack_chk_guard
+ && strncmp (SYMBOL_LINKAGE_NAME (stack_chk_guard), "__stack_chk_guard",
+ strlen ("__stack_chk_guard")) != 0)
+ return pc;
+
+ if (is_thumb)
+ {
+ unsigned int destreg;
+ unsigned short insn
+ = read_memory_unsigned_integer (pc + offset, 2, byte_order_for_code);
+
+ /* Step 2: ldr Rd, [Rn, #immed], encoding T1. */
+ if ((insn & 0xf800) != 0x6800)
+ return pc;
+ if (bits (insn, 3, 5) != basereg)
+ return pc;
+ destreg = bits (insn, 0, 2);
+
+ insn = read_memory_unsigned_integer (pc + offset + 2, 2,
+ byte_order_for_code);
+ /* Step 3: str Rd, [Rn, #immed], encoding T1. */
+ if ((insn & 0xf800) != 0x6000)
+ return pc;
+ if (destreg != bits (insn, 0, 2))
+ return pc;
+ }
+ else
+ {
+ unsigned int destreg;
+ unsigned int insn
+ = read_memory_unsigned_integer (pc + offset, 4, byte_order_for_code);
+
+ /* Step 2: ldr Rd, [Rn, #immed], encoding A1. */
+ if ((insn & 0x0e500000) != 0x04100000)
+ return pc;
+ if (bits (insn, 16, 19) != basereg)
+ return pc;
+ destreg = bits (insn, 12, 15);
+ /* Step 3: str Rd, [Rn, #immed], encoding A1. */
+ insn = read_memory_unsigned_integer (pc + offset + 4,
+ 4, byte_order_for_code);
+ if ((insn & 0x0e500000) != 0x04000000)
+ return pc;
+ if (bits (insn, 12, 15) != destreg)
+ return pc;
+ }
+ /* The size of total two instructions ldr/str is 4 on Thumb-2, while 8
+ on arm. */
+ if (is_thumb)
+ return pc + offset + 4;
+ else
+ return pc + offset + 8;
+}
+
+/* Advance the PC across any function entry prologue instructions to
+ reach some "real" code.
+
+ The APCS (ARM Procedure Call Standard) defines the following
+ prologue:
+
+ mov ip, sp
+ [stmfd sp!, {a1,a2,a3,a4}]
+ stmfd sp!, {...,fp,ip,lr,pc}
+ [stfe f7, [sp, #-12]!]
+ [stfe f6, [sp, #-12]!]
+ [stfe f5, [sp, #-12]!]
+ [stfe f4, [sp, #-12]!]
+ sub fp, ip, #nn @@ nn == 20 or 4 depending on second insn. */
+
+static CORE_ADDR
+arm_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned long inst;
+ CORE_ADDR skip_pc;
+ CORE_ADDR func_addr, limit_pc;
+ struct symtab_and_line sal;
+
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+ if (find_pc_partial_function (pc, NULL, &func_addr, NULL))
+ {
+ CORE_ADDR post_prologue_pc
+ = skip_prologue_using_sal (gdbarch, func_addr);
+ struct symtab *s = find_pc_symtab (func_addr);
+
+ if (post_prologue_pc)
+ post_prologue_pc
+ = arm_skip_stack_protector (post_prologue_pc, gdbarch);
+
+
+ /* GCC always emits a line note before the prologue and another
+ one after, even if the two are at the same address or on the
+ same line. Take advantage of this so that we do not need to
+ know every instruction that might appear in the prologue. We
+ will have producer information for most binaries; if it is
+ missing (e.g. for -gstabs), assuming the GNU tools. */
+ if (post_prologue_pc
+ && (s == NULL
+ || s->producer == NULL
+ || strncmp (s->producer, "GNU ", sizeof ("GNU ") - 1) == 0))
+ return post_prologue_pc;
+
+ if (post_prologue_pc != 0)
+ {
+ CORE_ADDR analyzed_limit;
+
+ /* For non-GCC compilers, make sure the entire line is an
+ acceptable prologue; GDB will round this function's
+ return value up to the end of the following line so we
+ can not skip just part of a line (and we do not want to).
+
+ RealView does not treat the prologue specially, but does
+ associate prologue code with the opening brace; so this
+ lets us skip the first line if we think it is the opening
+ brace. */
+ if (arm_pc_is_thumb (gdbarch, func_addr))
+ analyzed_limit = thumb_analyze_prologue (gdbarch, func_addr,
+ post_prologue_pc, NULL);
+ else
+ analyzed_limit = arm_analyze_prologue (gdbarch, func_addr,
+ post_prologue_pc, NULL);
+
+ if (analyzed_limit != post_prologue_pc)
+ return func_addr;
+
+ return post_prologue_pc;
+ }
+ }
+
+ /* Can't determine prologue from the symbol table, need to examine
+ instructions. */
+
+ /* Find an upper limit on the function prologue using the debug
+ information. If the debug information could not be used to provide
+ that bound, then use an arbitrary large number as the upper bound. */
+ /* Like arm_scan_prologue, stop no later than pc + 64. */
+ limit_pc = skip_prologue_using_sal (gdbarch, pc);
+ if (limit_pc == 0)
+ limit_pc = pc + 64; /* Magic. */
- /* Like arm_scan_prologue, stop no later than pc + 64. */
- if (func_end == 0 || func_end > pc + 64)
- func_end = pc + 64;
/* Check if this is Thumb code. */
- if (arm_pc_is_thumb (pc))
- return thumb_analyze_prologue (gdbarch, pc, func_end, NULL);
+ if (arm_pc_is_thumb (gdbarch, pc))
+ return thumb_analyze_prologue (gdbarch, pc, limit_pc, NULL);
- for (skip_pc = pc; skip_pc < func_end; skip_pc += 4)
+ for (skip_pc = pc; skip_pc < limit_pc; skip_pc += 4)
{
- inst = read_memory_unsigned_integer (skip_pc, 4);
+ inst = read_memory_unsigned_integer (skip_pc, 4, byte_order_for_code);
/* "mov ip, sp" is no longer a required part of the prologue. */
if (inst == 0xe1a0c00d) /* mov ip, sp */
if ((inst & 0xfffff000) == 0xe24dd000) /* sub sp, sp, #nn */
continue;
- if ((inst & 0xffffc000) == 0xe54b0000 || /* strb r(0123),[r11,#-nn] */
- (inst & 0xffffc0f0) == 0xe14b00b0 || /* strh r(0123),[r11,#-nn] */
- (inst & 0xffffc000) == 0xe50b0000) /* str r(0123),[r11,#-nn] */
+ if ((inst & 0xffffc000) == 0xe54b0000 /* strb r(0123),[r11,#-nn] */
+ || (inst & 0xffffc0f0) == 0xe14b00b0 /* strh r(0123),[r11,#-nn] */
+ || (inst & 0xffffc000) == 0xe50b0000) /* str r(0123),[r11,#-nn] */
continue;
- if ((inst & 0xffffc000) == 0xe5cd0000 || /* strb r(0123),[sp,#nn] */
- (inst & 0xffffc0f0) == 0xe1cd00b0 || /* strh r(0123),[sp,#nn] */
- (inst & 0xffffc000) == 0xe58d0000) /* str r(0123),[sp,#nn] */
+ if ((inst & 0xffffc000) == 0xe5cd0000 /* strb r(0123),[sp,#nn] */
+ || (inst & 0xffffc0f0) == 0xe1cd00b0 /* strh r(0123),[sp,#nn] */
+ || (inst & 0xffffc000) == 0xe58d0000) /* str r(0123),[sp,#nn] */
continue;
/* Un-recognized instruction; stop scanning. */
break;
}
- return skip_pc; /* End of prologue */
+ return skip_pc; /* End of prologue. */
}
/* *INDENT-OFF* */
R7 -> 0 local variables (16 bytes)
SP -> -12 additional stack space (12 bytes)
The frame size would thus be 36 bytes, and the frame offset would be
- 12 bytes. The frame register is R7.
+ 12 bytes. The frame register is R7.
The comments for thumb_skip_prolog() describe the algorithm we use
to detect the end of the prolog. */
static void
thumb_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR prev_pc,
- struct arm_prologue_cache *cache)
+ CORE_ADDR block_addr, struct arm_prologue_cache *cache)
{
CORE_ADDR prologue_start;
CORE_ADDR prologue_end;
CORE_ADDR current_pc;
- /* Which register has been copied to register n? */
- int saved_reg[16];
- /* findmask:
- bit 0 - push { rlist }
- bit 1 - mov r7, sp OR add r7, sp, #imm (setting of r7)
- bit 2 - sub sp, #simm OR add sp, #simm (adjusting of sp)
- */
- int findmask = 0;
- int i;
- if (find_pc_partial_function (prev_pc, NULL, &prologue_start, &prologue_end))
+ if (find_pc_partial_function (block_addr, NULL, &prologue_start,
+ &prologue_end))
{
- struct symtab_and_line sal = find_pc_line (prologue_start, 0);
-
- if (sal.line == 0) /* no line info, use current PC */
- prologue_end = prev_pc;
- else if (sal.end < prologue_end) /* next line begins after fn end */
- prologue_end = sal.end; /* (probably means no prologue) */
+ /* See comment in arm_scan_prologue for an explanation of
+ this heuristics. */
+ if (prologue_end > prologue_start + 64)
+ {
+ prologue_end = prologue_start + 64;
+ }
}
else
/* We're in the boondocks: we have no idea where the start of the
thumb_analyze_prologue (gdbarch, prologue_start, prologue_end, cache);
}
-/* This function decodes an ARM function prologue to determine:
- 1) the size of the stack frame
- 2) which registers are saved on it
- 3) the offsets of saved regs
- 4) the offset from the stack pointer to the frame pointer
- This information is stored in the "extra" fields of the frame_info.
-
- There are two basic forms for the ARM prologue. The fixed argument
- function call will look like:
-
- mov ip, sp
- stmfd sp!, {fp, ip, lr, pc}
- sub fp, ip, #4
- [sub sp, sp, #4]
-
- Which would create this stack frame (offsets relative to FP):
- IP -> 4 (caller's stack)
- FP -> 0 PC (points to address of stmfd instruction + 8 in callee)
- -4 LR (return address in caller)
- -8 IP (copy of caller's SP)
- -12 FP (caller's FP)
- SP -> -28 Local variables
-
- The frame size would thus be 32 bytes, and the frame offset would be
- 28 bytes. The stmfd call can also save any of the vN registers it
- plans to use, which increases the frame size accordingly.
-
- Note: The stored PC is 8 off of the STMFD instruction that stored it
- because the ARM Store instructions always store PC + 8 when you read
- the PC register.
-
- A variable argument function call will look like:
-
- mov ip, sp
- stmfd sp!, {a1, a2, a3, a4}
- stmfd sp!, {fp, ip, lr, pc}
- sub fp, ip, #20
-
- Which would create this stack frame (offsets relative to FP):
- IP -> 20 (caller's stack)
- 16 A4
- 12 A3
- 8 A2
- 4 A1
- FP -> 0 PC (points to address of stmfd instruction + 8 in callee)
- -4 LR (return address in caller)
- -8 IP (copy of caller's SP)
- -12 FP (caller's FP)
- SP -> -28 Local variables
-
- The frame size would thus be 48 bytes, and the frame offset would be
- 28 bytes.
-
- There is another potential complication, which is that the optimizer
- will try to separate the store of fp in the "stmfd" instruction from
- the "sub fp, ip, #NN" instruction. Almost anything can be there, so
- we just key on the stmfd, and then scan for the "sub fp, ip, #NN"...
-
- Also, note, the original version of the ARM toolchain claimed that there
- should be an
-
- instruction at the end of the prologue. I have never seen GCC produce
- this, and the ARM docs don't mention it. We still test for it below in
- case it happens...
-
- */
+/* Return 1 if THIS_INSTR might change control flow, 0 otherwise. */
-static void
-arm_scan_prologue (struct frame_info *this_frame,
- struct arm_prologue_cache *cache)
+static int
+arm_instruction_changes_pc (uint32_t this_instr)
{
- struct gdbarch *gdbarch = get_frame_arch (this_frame);
- int regno;
- CORE_ADDR prologue_start, prologue_end, current_pc;
- CORE_ADDR prev_pc = get_frame_pc (this_frame);
- pv_t regs[ARM_FPS_REGNUM];
- struct pv_area *stack;
- struct cleanup *back_to;
- CORE_ADDR offset;
+ if (bits (this_instr, 28, 31) == INST_NV)
+ /* Unconditional instructions. */
+ switch (bits (this_instr, 24, 27))
+ {
+ case 0xa:
+ case 0xb:
+ /* Branch with Link and change to Thumb. */
+ return 1;
+ case 0xc:
+ case 0xd:
+ case 0xe:
+ /* Coprocessor register transfer. */
+ if (bits (this_instr, 12, 15) == 15)
+ error (_("Invalid update to pc in instruction"));
+ return 0;
+ default:
+ return 0;
+ }
+ else
+ switch (bits (this_instr, 25, 27))
+ {
+ case 0x0:
+ if (bits (this_instr, 23, 24) == 2 && bit (this_instr, 20) == 0)
+ {
+ /* Multiplies and extra load/stores. */
+ if (bit (this_instr, 4) == 1 && bit (this_instr, 7) == 1)
+ /* Neither multiplies nor extension load/stores are allowed
+ to modify PC. */
+ return 0;
- /* Assume there is no frame until proven otherwise. */
- cache->framereg = ARM_SP_REGNUM;
- cache->framesize = 0;
+ /* Otherwise, miscellaneous instructions. */
- /* Check for Thumb prologue. */
- if (arm_pc_is_thumb (prev_pc))
- {
- thumb_scan_prologue (gdbarch, prev_pc, cache);
- return;
- }
+ /* BX <reg>, BXJ <reg>, BLX <reg> */
+ if (bits (this_instr, 4, 27) == 0x12fff1
+ || bits (this_instr, 4, 27) == 0x12fff2
+ || bits (this_instr, 4, 27) == 0x12fff3)
+ return 1;
- /* Find the function prologue. If we can't find the function in
- the symbol table, peek in the stack frame to find the PC. */
- if (find_pc_partial_function (prev_pc, NULL, &prologue_start, &prologue_end))
- {
- /* One way to find the end of the prologue (which works well
- for unoptimized code) is to do the following:
+ /* Other miscellaneous instructions are unpredictable if they
+ modify PC. */
+ return 0;
+ }
+ /* Data processing instruction. Fall through. */
+
+ case 0x1:
+ if (bits (this_instr, 12, 15) == 15)
+ return 1;
+ else
+ return 0;
+
+ case 0x2:
+ case 0x3:
+ /* Media instructions and architecturally undefined instructions. */
+ if (bits (this_instr, 25, 27) == 3 && bit (this_instr, 4) == 1)
+ return 0;
+
+ /* Stores. */
+ if (bit (this_instr, 20) == 0)
+ return 0;
+
+ /* Loads. */
+ if (bits (this_instr, 12, 15) == ARM_PC_REGNUM)
+ return 1;
+ else
+ return 0;
+
+ case 0x4:
+ /* Load/store multiple. */
+ if (bit (this_instr, 20) == 1 && bit (this_instr, 15) == 1)
+ return 1;
+ else
+ return 0;
+
+ case 0x5:
+ /* Branch and branch with link. */
+ return 1;
+
+ case 0x6:
+ case 0x7:
+ /* Coprocessor transfers or SWIs can not affect PC. */
+ return 0;
- struct symtab_and_line sal = find_pc_line (prologue_start, 0);
+ default:
+ internal_error (__FILE__, __LINE__, _("bad value in switch"));
+ }
+}
- if (sal.line == 0)
- prologue_end = prev_pc;
- else if (sal.end < prologue_end)
- prologue_end = sal.end;
+/* Analyze an ARM mode prologue starting at PROLOGUE_START and
+ continuing no further than PROLOGUE_END. If CACHE is non-NULL,
+ fill it in. Return the first address not recognized as a prologue
+ instruction.
- This mechanism is very accurate so long as the optimizer
- doesn't move any instructions from the function body into the
- prologue. If this happens, sal.end will be the last
- instruction in the first hunk of prologue code just before
- the first instruction that the scheduler has moved from
- the body to the prologue.
-
- In order to make sure that we scan all of the prologue
- instructions, we use a slightly less accurate mechanism which
- may scan more than necessary. To help compensate for this
- lack of accuracy, the prologue scanning loop below contains
- several clauses which'll cause the loop to terminate early if
- an implausible prologue instruction is encountered.
-
- The expression
-
- prologue_start + 64
-
- is a suitable endpoint since it accounts for the largest
- possible prologue plus up to five instructions inserted by
- the scheduler. */
-
- if (prologue_end > prologue_start + 64)
- {
- prologue_end = prologue_start + 64; /* See above. */
- }
- }
- else
- {
- /* We have no symbol information. Our only option is to assume this
- function has a standard stack frame and the normal frame register.
- Then, we can find the value of our frame pointer on entrance to
- the callee (or at the present moment if this is the innermost frame).
- The value stored there should be the address of the stmfd + 8. */
- CORE_ADDR frame_loc;
- LONGEST return_value;
-
- frame_loc = get_frame_register_unsigned (this_frame, ARM_FP_REGNUM);
- if (!safe_read_memory_integer (frame_loc, 4, &return_value))
- return;
- else
- {
- prologue_start = gdbarch_addr_bits_remove
- (gdbarch, return_value) - 8;
- prologue_end = prologue_start + 64; /* See above. */
- }
- }
+ We recognize all the instructions typically found in ARM prologues,
+ plus harmless instructions which can be skipped (either for analysis
+ purposes, or a more restrictive set that can be skipped when finding
+ the end of the prologue). */
- if (prev_pc < prologue_end)
- prologue_end = prev_pc;
+static CORE_ADDR
+arm_analyze_prologue (struct gdbarch *gdbarch,
+ CORE_ADDR prologue_start, CORE_ADDR prologue_end,
+ struct arm_prologue_cache *cache)
+{
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ int regno;
+ CORE_ADDR offset, current_pc;
+ pv_t regs[ARM_FPS_REGNUM];
+ struct pv_area *stack;
+ struct cleanup *back_to;
+ int framereg, framesize;
+ CORE_ADDR unrecognized_pc = 0;
- /* Now search the prologue looking for instructions that set up the
+ /* Search the prologue looking for instructions that set up the
frame pointer, adjust the stack pointer, and save registers.
Be careful, however, and if it doesn't look like a prologue,
begins with stmfd sp!, then we will tell ourselves there is
a frame, which will confuse stack traceback, as well as "finish"
and other operations that rely on a knowledge of the stack
- traceback.
-
- In the APCS, the prologue should start with "mov ip, sp" so
- if we don't see this as the first insn, we will stop.
-
- [Note: This doesn't seem to be true any longer, so it's now an
- optional part of the prologue. - Kevin Buettner, 2001-11-20]
-
- [Note further: The "mov ip,sp" only seems to be missing in
- frameless functions at optimization level "-O2" or above,
- in which case it is often (but not always) replaced by
- "str lr, [sp, #-4]!". - Michael Snyder, 2002-04-23] */
+ traceback. */
for (regno = 0; regno < ARM_FPS_REGNUM; regno++)
regs[regno] = pv_register (regno, 0);
- stack = make_pv_area (ARM_SP_REGNUM);
+ stack = make_pv_area (ARM_SP_REGNUM, gdbarch_addr_bit (gdbarch));
back_to = make_cleanup_free_pv_area (stack);
- regs[ARM_PC_REGNUM] = pv_unknown ();
-
for (current_pc = prologue_start;
current_pc < prologue_end;
current_pc += 4)
{
- unsigned int insn = read_memory_unsigned_integer (current_pc, 4);
+ unsigned int insn
+ = read_memory_unsigned_integer (current_pc, 4, byte_order_for_code);
if (insn == 0xe1a0c00d) /* mov ip, sp */
{
regs[ARM_IP_REGNUM] = regs[ARM_SP_REGNUM];
continue;
}
- else if ((insn & 0xfffff000) == 0xe28dc000) /* add ip, sp #n */
+ else if ((insn & 0xfff00000) == 0xe2800000 /* add Rd, Rn, #n */
+ && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
{
unsigned imm = insn & 0xff; /* immediate value */
unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
+ int rd = bits (insn, 12, 15);
imm = (imm >> rot) | (imm << (32 - rot));
- regs[ARM_IP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], imm);
+ regs[rd] = pv_add_constant (regs[bits (insn, 16, 19)], imm);
continue;
}
- else if ((insn & 0xfffff000) == 0xe24dc000) /* sub ip, sp #n */
+ else if ((insn & 0xfff00000) == 0xe2400000 /* sub Rd, Rn, #n */
+ && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
{
unsigned imm = insn & 0xff; /* immediate value */
unsigned rot = (insn & 0xf00) >> 7; /* rotate amount */
+ int rd = bits (insn, 12, 15);
imm = (imm >> rot) | (imm << (32 - rot));
- regs[ARM_IP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -imm);
+ regs[rd] = pv_add_constant (regs[bits (insn, 16, 19)], -imm);
continue;
}
- else if (insn == 0xe52de004) /* str lr, [sp, #-4]! */
+ else if ((insn & 0xffff0fff) == 0xe52d0004) /* str Rd,
+ [sp, #-4]! */
{
if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM]))
break;
regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -4);
- pv_area_store (stack, regs[ARM_SP_REGNUM], 4, regs[ARM_LR_REGNUM]);
+ pv_area_store (stack, regs[ARM_SP_REGNUM], 4,
+ regs[bits (insn, 12, 15)]);
continue;
}
else if ((insn & 0xffff0000) == 0xe92d0000)
for (regno = ARM_PC_REGNUM; regno >= 0; regno--)
if (mask & (1 << regno))
{
- regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -4);
+ regs[ARM_SP_REGNUM]
+ = pv_add_constant (regs[ARM_SP_REGNUM], -4);
pv_area_store (stack, regs[ARM_SP_REGNUM], 4, regs[regno]);
}
}
- else if ((insn & 0xffffc000) == 0xe54b0000 || /* strb rx,[r11,#-n] */
- (insn & 0xffffc0f0) == 0xe14b00b0 || /* strh rx,[r11,#-n] */
- (insn & 0xffffc000) == 0xe50b0000) /* str rx,[r11,#-n] */
+ else if ((insn & 0xffff0000) == 0xe54b0000 /* strb rx,[r11,#-n] */
+ || (insn & 0xffff00f0) == 0xe14b00b0 /* strh rx,[r11,#-n] */
+ || (insn & 0xffffc000) == 0xe50b0000) /* str rx,[r11,#-n] */
{
/* No need to add this to saved_regs -- it's just an arg reg. */
continue;
}
- else if ((insn & 0xffffc000) == 0xe5cd0000 || /* strb rx,[sp,#n] */
- (insn & 0xffffc0f0) == 0xe1cd00b0 || /* strh rx,[sp,#n] */
- (insn & 0xffffc000) == 0xe58d0000) /* str rx,[sp,#n] */
+ else if ((insn & 0xffff0000) == 0xe5cd0000 /* strb rx,[sp,#n] */
+ || (insn & 0xffff00f0) == 0xe1cd00b0 /* strh rx,[sp,#n] */
+ || (insn & 0xffffc000) == 0xe58d0000) /* str rx,[sp,#n] */
{
/* No need to add this to saved_regs -- it's just an arg reg. */
continue;
}
+ else if ((insn & 0xfff00000) == 0xe8800000 /* stm Rn,
+ { registers } */
+ && pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
+ {
+ /* No need to add this to saved_regs -- it's just arg regs. */
+ continue;
+ }
else if ((insn & 0xfffff000) == 0xe24cb000) /* sub fp, ip #n */
{
unsigned imm = insn & 0xff; /* immediate value */
imm = (imm >> rot) | (imm << (32 - rot));
regs[ARM_SP_REGNUM] = pv_add_constant (regs[ARM_SP_REGNUM], -imm);
}
- else if ((insn & 0xffff7fff) == 0xed6d0103 /* stfe f?, [sp, -#c]! */
+ else if ((insn & 0xffff7fff) == 0xed6d0103 /* stfe f?,
+ [sp, -#c]! */
&& gdbarch_tdep (gdbarch)->have_fpa_registers)
{
if (pv_area_store_would_trash (stack, regs[ARM_SP_REGNUM]))
regno = ARM_F0_REGNUM + ((insn >> 12) & 0x07);
pv_area_store (stack, regs[ARM_SP_REGNUM], 12, regs[regno]);
}
- else if ((insn & 0xffbf0fff) == 0xec2d0200 /* sfmfd f0, 4, [sp!] */
+ else if ((insn & 0xffbf0fff) == 0xec2d0200 /* sfmfd f0, 4,
+ [sp!] */
&& gdbarch_tdep (gdbarch)->have_fpa_registers)
{
int n_saved_fp_regs;
regs[fp_start_reg++]);
}
}
+ else if ((insn & 0xff000000) == 0xeb000000 && cache == NULL) /* bl */
+ {
+ /* Allow some special function calls when skipping the
+ prologue; GCC generates these before storing arguments to
+ the stack. */
+ CORE_ADDR dest = BranchDest (current_pc, insn);
+
+ if (skip_prologue_function (gdbarch, dest, 0))
+ continue;
+ else
+ break;
+ }
else if ((insn & 0xf0000000) != 0xe0000000)
- break; /* Condition not true, exit early */
- else if ((insn & 0xfe200000) == 0xe8200000) /* ldm? */
- break; /* Don't scan past a block load */
- else
- /* The optimizer might shove anything into the prologue,
- so we just skip what we don't recognize. */
+ break; /* Condition not true, exit early. */
+ else if (arm_instruction_changes_pc (insn))
+ /* Don't scan past anything that might change control flow. */
+ break;
+ else if ((insn & 0xfe500000) == 0xe8100000) /* ldm */
+ {
+ /* Ignore block loads from the stack, potentially copying
+ parameters from memory. */
+ if (pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
+ continue;
+ else
+ break;
+ }
+ else if ((insn & 0xfc500000) == 0xe4100000)
+ {
+ /* Similarly ignore single loads from the stack. */
+ if (pv_is_register (regs[bits (insn, 16, 19)], ARM_SP_REGNUM))
+ continue;
+ else
+ break;
+ }
+ else if ((insn & 0xffff0ff0) == 0xe1a00000)
+ /* MOV Rd, Rm. Skip register copies, i.e. saves to another
+ register instead of the stack. */
continue;
+ else
+ {
+ /* The optimizer might shove anything into the prologue,
+ so we just skip what we don't recognize. */
+ unrecognized_pc = current_pc;
+ continue;
+ }
}
+ if (unrecognized_pc == 0)
+ unrecognized_pc = current_pc;
+
/* The frame size is just the distance from the frame register
to the original stack pointer. */
if (pv_is_register (regs[ARM_FP_REGNUM], ARM_SP_REGNUM))
{
/* Frame pointer is fp. */
- cache->framereg = ARM_FP_REGNUM;
- cache->framesize = -regs[ARM_FP_REGNUM].k;
+ framereg = ARM_FP_REGNUM;
+ framesize = -regs[ARM_FP_REGNUM].k;
}
else if (pv_is_register (regs[ARM_SP_REGNUM], ARM_SP_REGNUM))
{
/* Try the stack pointer... this is a bit desperate. */
- cache->framereg = ARM_SP_REGNUM;
- cache->framesize = -regs[ARM_SP_REGNUM].k;
+ framereg = ARM_SP_REGNUM;
+ framesize = -regs[ARM_SP_REGNUM].k;
}
else
{
/* We're just out of luck. We don't know where the frame is. */
- cache->framereg = -1;
- cache->framesize = 0;
+ framereg = -1;
+ framesize = 0;
}
- for (regno = 0; regno < ARM_FPS_REGNUM; regno++)
- if (pv_area_find_reg (stack, gdbarch, regno, &offset))
- cache->saved_regs[regno].addr = offset;
+ if (cache)
+ {
+ cache->framereg = framereg;
+ cache->framesize = framesize;
+
+ for (regno = 0; regno < ARM_FPS_REGNUM; regno++)
+ if (pv_area_find_reg (stack, gdbarch, regno, &offset))
+ cache->saved_regs[regno].addr = offset;
+ }
+
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "Prologue scan stopped at %s\n",
+ paddress (gdbarch, unrecognized_pc));
do_cleanups (back_to);
+ return unrecognized_pc;
+}
+
+static void
+arm_scan_prologue (struct frame_info *this_frame,
+ struct arm_prologue_cache *cache)
+{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int regno;
+ CORE_ADDR prologue_start, prologue_end, current_pc;
+ CORE_ADDR prev_pc = get_frame_pc (this_frame);
+ CORE_ADDR block_addr = get_frame_address_in_block (this_frame);
+ pv_t regs[ARM_FPS_REGNUM];
+ struct pv_area *stack;
+ struct cleanup *back_to;
+ CORE_ADDR offset;
+
+ /* Assume there is no frame until proven otherwise. */
+ cache->framereg = ARM_SP_REGNUM;
+ cache->framesize = 0;
+
+ /* Check for Thumb prologue. */
+ if (arm_frame_is_thumb (this_frame))
+ {
+ thumb_scan_prologue (gdbarch, prev_pc, block_addr, cache);
+ return;
+ }
+
+ /* Find the function prologue. If we can't find the function in
+ the symbol table, peek in the stack frame to find the PC. */
+ if (find_pc_partial_function (block_addr, NULL, &prologue_start,
+ &prologue_end))
+ {
+ /* One way to find the end of the prologue (which works well
+ for unoptimized code) is to do the following:
+
+ struct symtab_and_line sal = find_pc_line (prologue_start, 0);
+
+ if (sal.line == 0)
+ prologue_end = prev_pc;
+ else if (sal.end < prologue_end)
+ prologue_end = sal.end;
+
+ This mechanism is very accurate so long as the optimizer
+ doesn't move any instructions from the function body into the
+ prologue. If this happens, sal.end will be the last
+ instruction in the first hunk of prologue code just before
+ the first instruction that the scheduler has moved from
+ the body to the prologue.
+
+ In order to make sure that we scan all of the prologue
+ instructions, we use a slightly less accurate mechanism which
+ may scan more than necessary. To help compensate for this
+ lack of accuracy, the prologue scanning loop below contains
+ several clauses which'll cause the loop to terminate early if
+ an implausible prologue instruction is encountered.
+
+ The expression
+
+ prologue_start + 64
+
+ is a suitable endpoint since it accounts for the largest
+ possible prologue plus up to five instructions inserted by
+ the scheduler. */
+
+ if (prologue_end > prologue_start + 64)
+ {
+ prologue_end = prologue_start + 64; /* See above. */
+ }
+ }
+ else
+ {
+ /* We have no symbol information. Our only option is to assume this
+ function has a standard stack frame and the normal frame register.
+ Then, we can find the value of our frame pointer on entrance to
+ the callee (or at the present moment if this is the innermost frame).
+ The value stored there should be the address of the stmfd + 8. */
+ CORE_ADDR frame_loc;
+ LONGEST return_value;
+
+ frame_loc = get_frame_register_unsigned (this_frame, ARM_FP_REGNUM);
+ if (!safe_read_memory_integer (frame_loc, 4, byte_order, &return_value))
+ return;
+ else
+ {
+ prologue_start = gdbarch_addr_bits_remove
+ (gdbarch, return_value) - 8;
+ prologue_end = prologue_start + 64; /* See above. */
+ }
+ }
+
+ if (prev_pc < prologue_end)
+ prologue_end = prev_pc;
+
+ arm_analyze_prologue (gdbarch, prologue_start, prologue_end, cache);
}
static struct arm_prologue_cache *
{
struct arm_prologue_cache *cache;
struct frame_id id;
- CORE_ADDR func;
+ CORE_ADDR pc, func;
if (*this_cache == NULL)
*this_cache = arm_make_prologue_cache (this_frame);
cache = *this_cache;
- func = get_frame_func (this_frame);
-
- /* This is meant to halt the backtrace at "_start". Make sure we
- don't halt it at a generic dummy frame. */
- if (func <= gdbarch_tdep (get_frame_arch (this_frame))->lowest_pc)
+ /* This is meant to halt the backtrace at "_start". */
+ pc = get_frame_pc (this_frame);
+ if (pc <= gdbarch_tdep (get_frame_arch (this_frame))->lowest_pc)
return;
/* If we've hit a wall, stop. */
if (cache->prev_sp == 0)
return;
+ /* Use function start address as part of the frame ID. If we cannot
+ identify the start address (due to missing symbol information),
+ fall back to just using the current PC. */
+ func = get_frame_func (this_frame);
+ if (!func)
+ func = pc;
+
id = frame_id_build (cache->prev_sp, func);
*this_id = id;
}
void **this_cache,
int prev_regnum)
{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct arm_prologue_cache *cache;
if (*this_cache == NULL)
cache = *this_cache;
/* If we are asked to unwind the PC, then we need to return the LR
- instead. The saved value of PC points into this frame's
- prologue, not the next frame's resume location. */
+ instead. The prologue may save PC, but it will point into this
+ frame's prologue, not the next frame's resume location. Also
+ strip the saved T bit. A valid LR may have the low bit set, but
+ a valid PC never does. */
if (prev_regnum == ARM_PC_REGNUM)
- prev_regnum = ARM_LR_REGNUM;
+ {
+ CORE_ADDR lr;
+
+ lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
+ return frame_unwind_got_constant (this_frame, prev_regnum,
+ arm_addr_bits_remove (gdbarch, lr));
+ }
/* SP is generally not saved to the stack, but this frame is
identified by the next frame's stack pointer at the time of the call.
if (prev_regnum == ARM_SP_REGNUM)
return frame_unwind_got_constant (this_frame, prev_regnum, cache->prev_sp);
+ /* The CPSR may have been changed by the call instruction and by the
+ called function. The only bit we can reconstruct is the T bit,
+ by checking the low bit of LR as of the call. This is a reliable
+ indicator of Thumb-ness except for some ARM v4T pre-interworking
+ Thumb code, which could get away with a clear low bit as long as
+ the called function did not use bx. Guess that all other
+ bits are unchanged; the condition flags are presumably lost,
+ but the processor status is likely valid. */
+ if (prev_regnum == ARM_PS_REGNUM)
+ {
+ CORE_ADDR lr, cpsr;
+ ULONGEST t_bit = arm_psr_thumb_bit (gdbarch);
+
+ cpsr = get_frame_register_unsigned (this_frame, prev_regnum);
+ lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
+ if (IS_THUMB_ADDR (lr))
+ cpsr |= t_bit;
+ else
+ cpsr &= ~t_bit;
+ return frame_unwind_got_constant (this_frame, prev_regnum, cpsr);
+ }
+
return trad_frame_get_prev_register (this_frame, cache->saved_regs,
prev_regnum);
}
default_frame_sniffer
};
-static struct arm_prologue_cache *
-arm_make_stub_cache (struct frame_info *this_frame)
-{
- int reg;
- struct arm_prologue_cache *cache;
- CORE_ADDR unwound_fp;
-
- cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache);
- cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
+/* Maintain a list of ARM exception table entries per objfile, similar to the
+ list of mapping symbols. We only cache entries for standard ARM-defined
+ personality routines; the cache will contain only the frame unwinding
+ instructions associated with the entry (not the descriptors). */
- cache->prev_sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM);
+static const struct objfile_data *arm_exidx_data_key;
- return cache;
-}
+struct arm_exidx_entry
+{
+ bfd_vma addr;
+ gdb_byte *entry;
+};
+typedef struct arm_exidx_entry arm_exidx_entry_s;
+DEF_VEC_O(arm_exidx_entry_s);
-/* Our frame ID for a stub frame is the current SP and LR. */
+struct arm_exidx_data
+{
+ VEC(arm_exidx_entry_s) **section_maps;
+};
static void
-arm_stub_this_id (struct frame_info *this_frame,
- void **this_cache,
- struct frame_id *this_id)
+arm_exidx_data_free (struct objfile *objfile, void *arg)
{
- struct arm_prologue_cache *cache;
+ struct arm_exidx_data *data = arg;
+ unsigned int i;
- if (*this_cache == NULL)
- *this_cache = arm_make_stub_cache (this_frame);
- cache = *this_cache;
+ for (i = 0; i < objfile->obfd->section_count; i++)
+ VEC_free (arm_exidx_entry_s, data->section_maps[i]);
+}
- *this_id = frame_id_build (cache->prev_sp, get_frame_pc (this_frame));
+static inline int
+arm_compare_exidx_entries (const struct arm_exidx_entry *lhs,
+ const struct arm_exidx_entry *rhs)
+{
+ return lhs->addr < rhs->addr;
}
-static int
-arm_stub_unwind_sniffer (const struct frame_unwind *self,
- struct frame_info *this_frame,
- void **this_prologue_cache)
+static struct obj_section *
+arm_obj_section_from_vma (struct objfile *objfile, bfd_vma vma)
{
- CORE_ADDR addr_in_block;
- char dummy[4];
+ struct obj_section *osect;
- addr_in_block = get_frame_address_in_block (this_frame);
- if (in_plt_section (addr_in_block, NULL)
- || target_read_memory (get_frame_pc (this_frame), dummy, 4) != 0)
- return 1;
+ ALL_OBJFILE_OSECTIONS (objfile, osect)
+ if (bfd_get_section_flags (objfile->obfd,
+ osect->the_bfd_section) & SEC_ALLOC)
+ {
+ bfd_vma start, size;
+ start = bfd_get_section_vma (objfile->obfd, osect->the_bfd_section);
+ size = bfd_get_section_size (osect->the_bfd_section);
- return 0;
+ if (start <= vma && vma < start + size)
+ return osect;
+ }
+
+ return NULL;
}
-struct frame_unwind arm_stub_unwind = {
- NORMAL_FRAME,
- arm_stub_this_id,
- arm_prologue_prev_register,
- NULL,
- arm_stub_unwind_sniffer
-};
+/* Parse contents of exception table and exception index sections
+ of OBJFILE, and fill in the exception table entry cache.
-static CORE_ADDR
-arm_normal_frame_base (struct frame_info *this_frame, void **this_cache)
+ For each entry that refers to a standard ARM-defined personality
+ routine, extract the frame unwinding instructions (from either
+ the index or the table section). The unwinding instructions
+ are normalized by:
+ - extracting them from the rest of the table data
+ - converting to host endianness
+ - appending the implicit 0xb0 ("Finish") code
+
+ The extracted and normalized instructions are stored for later
+ retrieval by the arm_find_exidx_entry routine. */
+
+static void
+arm_exidx_new_objfile (struct objfile *objfile)
{
- struct arm_prologue_cache *cache;
+ struct cleanup *cleanups = make_cleanup (null_cleanup, NULL);
+ struct arm_exidx_data *data;
+ asection *exidx, *extab;
+ bfd_vma exidx_vma = 0, extab_vma = 0;
+ bfd_size_type exidx_size = 0, extab_size = 0;
+ gdb_byte *exidx_data = NULL, *extab_data = NULL;
+ LONGEST i;
+
+ /* If we've already touched this file, do nothing. */
+ if (!objfile || objfile_data (objfile, arm_exidx_data_key) != NULL)
+ return;
- if (*this_cache == NULL)
- *this_cache = arm_make_prologue_cache (this_frame);
- cache = *this_cache;
+ /* Read contents of exception table and index. */
+ exidx = bfd_get_section_by_name (objfile->obfd, ".ARM.exidx");
+ if (exidx)
+ {
+ exidx_vma = bfd_section_vma (objfile->obfd, exidx);
+ exidx_size = bfd_get_section_size (exidx);
+ exidx_data = xmalloc (exidx_size);
+ make_cleanup (xfree, exidx_data);
- return cache->prev_sp - cache->framesize;
-}
+ if (!bfd_get_section_contents (objfile->obfd, exidx,
+ exidx_data, 0, exidx_size))
+ {
+ do_cleanups (cleanups);
+ return;
+ }
+ }
-struct frame_base arm_normal_base = {
- &arm_prologue_unwind,
- arm_normal_frame_base,
- arm_normal_frame_base,
- arm_normal_frame_base
-};
+ extab = bfd_get_section_by_name (objfile->obfd, ".ARM.extab");
+ if (extab)
+ {
+ extab_vma = bfd_section_vma (objfile->obfd, extab);
+ extab_size = bfd_get_section_size (extab);
+ extab_data = xmalloc (extab_size);
+ make_cleanup (xfree, extab_data);
-/* Assuming THIS_FRAME is a dummy, return the frame ID of that
- dummy frame. The frame ID's base needs to match the TOS value
- saved by save_dummy_frame_tos() and returned from
- arm_push_dummy_call, and the PC needs to match the dummy frame's
- breakpoint. */
+ if (!bfd_get_section_contents (objfile->obfd, extab,
+ extab_data, 0, extab_size))
+ {
+ do_cleanups (cleanups);
+ return;
+ }
+ }
-static struct frame_id
-arm_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
-{
- return frame_id_build (get_frame_register_unsigned (this_frame, ARM_SP_REGNUM),
- get_frame_pc (this_frame));
-}
+ /* Allocate exception table data structure. */
+ data = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct arm_exidx_data);
+ set_objfile_data (objfile, arm_exidx_data_key, data);
+ data->section_maps = OBSTACK_CALLOC (&objfile->objfile_obstack,
+ objfile->obfd->section_count,
+ VEC(arm_exidx_entry_s) *);
-/* Given THIS_FRAME, find the previous frame's resume PC (which will
- be used to construct the previous frame's ID, after looking up the
- containing function). */
+ /* Fill in exception table. */
+ for (i = 0; i < exidx_size / 8; i++)
+ {
+ struct arm_exidx_entry new_exidx_entry;
+ bfd_vma idx = bfd_h_get_32 (objfile->obfd, exidx_data + i * 8);
+ bfd_vma val = bfd_h_get_32 (objfile->obfd, exidx_data + i * 8 + 4);
+ bfd_vma addr = 0, word = 0;
+ int n_bytes = 0, n_words = 0;
+ struct obj_section *sec;
+ gdb_byte *entry = NULL;
-static CORE_ADDR
-arm_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
-{
- CORE_ADDR pc;
- pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM);
- return arm_addr_bits_remove (pc);
-}
+ /* Extract address of start of function. */
+ idx = ((idx & 0x7fffffff) ^ 0x40000000) - 0x40000000;
+ idx += exidx_vma + i * 8;
-static CORE_ADDR
-arm_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
-{
- return frame_unwind_register_unsigned (this_frame, ARM_SP_REGNUM);
-}
+ /* Find section containing function and compute section offset. */
+ sec = arm_obj_section_from_vma (objfile, idx);
+ if (sec == NULL)
+ continue;
+ idx -= bfd_get_section_vma (objfile->obfd, sec->the_bfd_section);
-/* When arguments must be pushed onto the stack, they go on in reverse
- order. The code below implements a FILO (stack) to do this. */
+ /* Determine address of exception table entry. */
+ if (val == 1)
+ {
+ /* EXIDX_CANTUNWIND -- no exception table entry present. */
+ }
+ else if ((val & 0xff000000) == 0x80000000)
+ {
+ /* Exception table entry embedded in .ARM.exidx
+ -- must be short form. */
+ word = val;
+ n_bytes = 3;
+ }
+ else if (!(val & 0x80000000))
+ {
+ /* Exception table entry in .ARM.extab. */
+ addr = ((val & 0x7fffffff) ^ 0x40000000) - 0x40000000;
+ addr += exidx_vma + i * 8 + 4;
-struct stack_item
-{
- int len;
- struct stack_item *prev;
- void *data;
-};
+ if (addr >= extab_vma && addr + 4 <= extab_vma + extab_size)
+ {
+ word = bfd_h_get_32 (objfile->obfd,
+ extab_data + addr - extab_vma);
+ addr += 4;
-static struct stack_item *
-push_stack_item (struct stack_item *prev, void *contents, int len)
-{
- struct stack_item *si;
- si = xmalloc (sizeof (struct stack_item));
- si->data = xmalloc (len);
- si->len = len;
- si->prev = prev;
- memcpy (si->data, contents, len);
- return si;
-}
+ if ((word & 0xff000000) == 0x80000000)
+ {
+ /* Short form. */
+ n_bytes = 3;
+ }
+ else if ((word & 0xff000000) == 0x81000000
+ || (word & 0xff000000) == 0x82000000)
+ {
+ /* Long form. */
+ n_bytes = 2;
+ n_words = ((word >> 16) & 0xff);
+ }
+ else if (!(word & 0x80000000))
+ {
+ bfd_vma pers;
+ struct obj_section *pers_sec;
+ int gnu_personality = 0;
+
+ /* Custom personality routine. */
+ pers = ((word & 0x7fffffff) ^ 0x40000000) - 0x40000000;
+ pers = UNMAKE_THUMB_ADDR (pers + addr - 4);
+
+ /* Check whether we've got one of the variants of the
+ GNU personality routines. */
+ pers_sec = arm_obj_section_from_vma (objfile, pers);
+ if (pers_sec)
+ {
+ static const char *personality[] =
+ {
+ "__gcc_personality_v0",
+ "__gxx_personality_v0",
+ "__gcj_personality_v0",
+ "__gnu_objc_personality_v0",
+ NULL
+ };
+
+ CORE_ADDR pc = pers + obj_section_offset (pers_sec);
+ int k;
+
+ for (k = 0; personality[k]; k++)
+ if (lookup_minimal_symbol_by_pc_name
+ (pc, personality[k], objfile))
+ {
+ gnu_personality = 1;
+ break;
+ }
+ }
-static struct stack_item *
-pop_stack_item (struct stack_item *si)
-{
- struct stack_item *dead = si;
- si = si->prev;
- xfree (dead->data);
- xfree (dead);
- return si;
-}
+ /* If so, the next word contains a word count in the high
+ byte, followed by the same unwind instructions as the
+ pre-defined forms. */
+ if (gnu_personality
+ && addr + 4 <= extab_vma + extab_size)
+ {
+ word = bfd_h_get_32 (objfile->obfd,
+ extab_data + addr - extab_vma);
+ addr += 4;
+ n_bytes = 3;
+ n_words = ((word >> 24) & 0xff);
+ }
+ }
+ }
+ }
+ /* Sanity check address. */
+ if (n_words)
+ if (addr < extab_vma || addr + 4 * n_words > extab_vma + extab_size)
+ n_words = n_bytes = 0;
-/* Return the alignment (in bytes) of the given type. */
+ /* The unwind instructions reside in WORD (only the N_BYTES least
+ significant bytes are valid), followed by N_WORDS words in the
+ extab section starting at ADDR. */
+ if (n_bytes || n_words)
+ {
+ gdb_byte *p = entry = obstack_alloc (&objfile->objfile_obstack,
+ n_bytes + n_words * 4 + 1);
-static int
-arm_type_align (struct type *t)
+ while (n_bytes--)
+ *p++ = (gdb_byte) ((word >> (8 * n_bytes)) & 0xff);
+
+ while (n_words--)
+ {
+ word = bfd_h_get_32 (objfile->obfd,
+ extab_data + addr - extab_vma);
+ addr += 4;
+
+ *p++ = (gdb_byte) ((word >> 24) & 0xff);
+ *p++ = (gdb_byte) ((word >> 16) & 0xff);
+ *p++ = (gdb_byte) ((word >> 8) & 0xff);
+ *p++ = (gdb_byte) (word & 0xff);
+ }
+
+ /* Implied "Finish" to terminate the list. */
+ *p++ = 0xb0;
+ }
+
+ /* Push entry onto vector. They are guaranteed to always
+ appear in order of increasing addresses. */
+ new_exidx_entry.addr = idx;
+ new_exidx_entry.entry = entry;
+ VEC_safe_push (arm_exidx_entry_s,
+ data->section_maps[sec->the_bfd_section->index],
+ &new_exidx_entry);
+ }
+
+ do_cleanups (cleanups);
+}
+
+/* Search for the exception table entry covering MEMADDR. If one is found,
+ return a pointer to its data. Otherwise, return 0. If START is non-NULL,
+ set *START to the start of the region covered by this entry. */
+
+static gdb_byte *
+arm_find_exidx_entry (CORE_ADDR memaddr, CORE_ADDR *start)
{
- int n;
- int align;
- int falign;
+ struct obj_section *sec;
- t = check_typedef (t);
- switch (TYPE_CODE (t))
+ sec = find_pc_section (memaddr);
+ if (sec != NULL)
{
- default:
- /* Should never happen. */
- internal_error (__FILE__, __LINE__, _("unknown type alignment"));
- return 4;
+ struct arm_exidx_data *data;
+ VEC(arm_exidx_entry_s) *map;
+ struct arm_exidx_entry map_key = { memaddr - obj_section_addr (sec), 0 };
+ unsigned int idx;
- case TYPE_CODE_PTR:
- case TYPE_CODE_ENUM:
- case TYPE_CODE_INT:
- case TYPE_CODE_FLT:
- case TYPE_CODE_SET:
- case TYPE_CODE_RANGE:
- case TYPE_CODE_BITSTRING:
- case TYPE_CODE_REF:
- case TYPE_CODE_CHAR:
- case TYPE_CODE_BOOL:
- return TYPE_LENGTH (t);
+ data = objfile_data (sec->objfile, arm_exidx_data_key);
+ if (data != NULL)
+ {
+ map = data->section_maps[sec->the_bfd_section->index];
+ if (!VEC_empty (arm_exidx_entry_s, map))
+ {
+ struct arm_exidx_entry *map_sym;
- case TYPE_CODE_ARRAY:
- case TYPE_CODE_COMPLEX:
- /* TODO: What about vector types? */
- return arm_type_align (TYPE_TARGET_TYPE (t));
+ idx = VEC_lower_bound (arm_exidx_entry_s, map, &map_key,
+ arm_compare_exidx_entries);
- case TYPE_CODE_STRUCT:
- case TYPE_CODE_UNION:
- align = 1;
- for (n = 0; n < TYPE_NFIELDS (t); n++)
- {
- falign = arm_type_align (TYPE_FIELD_TYPE (t, n));
- if (falign > align)
- align = falign;
+ /* VEC_lower_bound finds the earliest ordered insertion
+ point. If the following symbol starts at this exact
+ address, we use that; otherwise, the preceding
+ exception table entry covers this address. */
+ if (idx < VEC_length (arm_exidx_entry_s, map))
+ {
+ map_sym = VEC_index (arm_exidx_entry_s, map, idx);
+ if (map_sym->addr == map_key.addr)
+ {
+ if (start)
+ *start = map_sym->addr + obj_section_addr (sec);
+ return map_sym->entry;
+ }
+ }
+
+ if (idx > 0)
+ {
+ map_sym = VEC_index (arm_exidx_entry_s, map, idx - 1);
+ if (start)
+ *start = map_sym->addr + obj_section_addr (sec);
+ return map_sym->entry;
+ }
+ }
}
- return align;
}
-}
-/* We currently only support passing parameters in integer registers. This
- conforms with GCC's default model. Several other variants exist and
- we should probably support some of them based on the selected ABI. */
+ return NULL;
+}
-static CORE_ADDR
-arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
- struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
- struct value **args, CORE_ADDR sp, int struct_return,
- CORE_ADDR struct_addr)
-{
- int argnum;
- int argreg;
- int nstack;
- struct stack_item *si = NULL;
+/* Given the current frame THIS_FRAME, and its associated frame unwinding
+ instruction list from the ARM exception table entry ENTRY, allocate and
+ return a prologue cache structure describing how to unwind this frame.
- /* Set the return address. For the ARM, the return breakpoint is
- always at BP_ADDR. */
- /* XXX Fix for Thumb. */
- regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr);
+ Return NULL if the unwinding instruction list contains a "spare",
+ "reserved" or "refuse to unwind" instruction as defined in section
+ "9.3 Frame unwinding instructions" of the "Exception Handling ABI
+ for the ARM Architecture" document. */
- /* Walk through the list of args and determine how large a temporary
- stack is required. Need to take care here as structs may be
- passed on the stack, and we have to to push them. */
- nstack = 0;
+static struct arm_prologue_cache *
+arm_exidx_fill_cache (struct frame_info *this_frame, gdb_byte *entry)
+{
+ CORE_ADDR vsp = 0;
+ int vsp_valid = 0;
- argreg = ARM_A1_REGNUM;
- nstack = 0;
+ struct arm_prologue_cache *cache;
+ cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache);
+ cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
- /* The struct_return pointer occupies the first parameter
- passing register. */
- if (struct_return)
+ for (;;)
{
- if (arm_debug)
- fprintf_unfiltered (gdb_stdlog, "struct return in %s = 0x%s\n",
- gdbarch_register_name (gdbarch, argreg),
- paddr (struct_addr));
- regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
- argreg++;
- }
+ gdb_byte insn;
- for (argnum = 0; argnum < nargs; argnum++)
- {
- int len;
- struct type *arg_type;
- struct type *target_type;
- enum type_code typecode;
- bfd_byte *val;
- int align;
+ /* Whenever we reload SP, we actually have to retrieve its
+ actual value in the current frame. */
+ if (!vsp_valid)
+ {
+ if (trad_frame_realreg_p (cache->saved_regs, ARM_SP_REGNUM))
+ {
+ int reg = cache->saved_regs[ARM_SP_REGNUM].realreg;
+ vsp = get_frame_register_unsigned (this_frame, reg);
+ }
+ else
+ {
+ CORE_ADDR addr = cache->saved_regs[ARM_SP_REGNUM].addr;
+ vsp = get_frame_memory_unsigned (this_frame, addr, 4);
+ }
- arg_type = check_typedef (value_type (args[argnum]));
- len = TYPE_LENGTH (arg_type);
- target_type = TYPE_TARGET_TYPE (arg_type);
- typecode = TYPE_CODE (arg_type);
- val = value_contents_writeable (args[argnum]);
+ vsp_valid = 1;
+ }
- align = arm_type_align (arg_type);
- /* Round alignment up to a whole number of words. */
- align = (align + INT_REGISTER_SIZE - 1) & ~(INT_REGISTER_SIZE - 1);
- /* Different ABIs have different maximum alignments. */
- if (gdbarch_tdep (gdbarch)->arm_abi == ARM_ABI_APCS)
+ /* Decode next unwind instruction. */
+ insn = *entry++;
+
+ if ((insn & 0xc0) == 0)
{
- /* The APCS ABI only requires word alignment. */
- align = INT_REGISTER_SIZE;
+ int offset = insn & 0x3f;
+ vsp += (offset << 2) + 4;
}
- else
+ else if ((insn & 0xc0) == 0x40)
{
- /* The AAPCS requires at most doubleword alignment. */
- if (align > INT_REGISTER_SIZE * 2)
- align = INT_REGISTER_SIZE * 2;
+ int offset = insn & 0x3f;
+ vsp -= (offset << 2) + 4;
}
-
- /* Push stack padding for dowubleword alignment. */
- if (nstack & (align - 1))
+ else if ((insn & 0xf0) == 0x80)
{
- si = push_stack_item (si, val, INT_REGISTER_SIZE);
- nstack += INT_REGISTER_SIZE;
+ int mask = ((insn & 0xf) << 8) | *entry++;
+ int i;
+
+ /* The special case of an all-zero mask identifies
+ "Refuse to unwind". We return NULL to fall back
+ to the prologue analyzer. */
+ if (mask == 0)
+ return NULL;
+
+ /* Pop registers r4..r15 under mask. */
+ for (i = 0; i < 12; i++)
+ if (mask & (1 << i))
+ {
+ cache->saved_regs[4 + i].addr = vsp;
+ vsp += 4;
+ }
+
+ /* Special-case popping SP -- we need to reload vsp. */
+ if (mask & (1 << (ARM_SP_REGNUM - 4)))
+ vsp_valid = 0;
}
-
- /* Doubleword aligned quantities must go in even register pairs. */
- if (argreg <= ARM_LAST_ARG_REGNUM
- && align > INT_REGISTER_SIZE
- && argreg & 1)
- argreg++;
+ else if ((insn & 0xf0) == 0x90)
+ {
+ int reg = insn & 0xf;
- /* If the argument is a pointer to a function, and it is a
- Thumb function, create a LOCAL copy of the value and set
- the THUMB bit in it. */
- if (TYPE_CODE_PTR == typecode
- && target_type != NULL
- && TYPE_CODE_FUNC == TYPE_CODE (target_type))
+ /* Reserved cases. */
+ if (reg == ARM_SP_REGNUM || reg == ARM_PC_REGNUM)
+ return NULL;
+
+ /* Set SP from another register and mark VSP for reload. */
+ cache->saved_regs[ARM_SP_REGNUM] = cache->saved_regs[reg];
+ vsp_valid = 0;
+ }
+ else if ((insn & 0xf0) == 0xa0)
{
- CORE_ADDR regval = extract_unsigned_integer (val, len);
- if (arm_pc_is_thumb (regval))
+ int count = insn & 0x7;
+ int pop_lr = (insn & 0x8) != 0;
+ int i;
+
+ /* Pop r4..r[4+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[4 + i].addr = vsp;
+ vsp += 4;
+ }
+
+ /* If indicated by flag, pop LR as well. */
+ if (pop_lr)
{
- val = alloca (len);
- store_unsigned_integer (val, len, MAKE_THUMB_ADDR (regval));
+ cache->saved_regs[ARM_LR_REGNUM].addr = vsp;
+ vsp += 4;
}
}
+ else if (insn == 0xb0)
+ {
+ /* We could only have updated PC by popping into it; if so, it
+ will show up as address. Otherwise, copy LR into PC. */
+ if (!trad_frame_addr_p (cache->saved_regs, ARM_PC_REGNUM))
+ cache->saved_regs[ARM_PC_REGNUM]
+ = cache->saved_regs[ARM_LR_REGNUM];
- /* Copy the argument to general registers or the stack in
- register-sized pieces. Large arguments are split between
- registers and stack. */
- while (len > 0)
+ /* We're done. */
+ break;
+ }
+ else if (insn == 0xb1)
{
- int partial_len = len < INT_REGISTER_SIZE ? len : INT_REGISTER_SIZE;
+ int mask = *entry++;
+ int i;
+
+ /* All-zero mask and mask >= 16 is "spare". */
+ if (mask == 0 || mask >= 16)
+ return NULL;
+
+ /* Pop r0..r3 under mask. */
+ for (i = 0; i < 4; i++)
+ if (mask & (1 << i))
+ {
+ cache->saved_regs[i].addr = vsp;
+ vsp += 4;
+ }
+ }
+ else if (insn == 0xb2)
+ {
+ ULONGEST offset = 0;
+ unsigned shift = 0;
- if (argreg <= ARM_LAST_ARG_REGNUM)
+ do
{
- /* The argument is being passed in a general purpose
- register. */
- CORE_ADDR regval = extract_unsigned_integer (val, partial_len);
- if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
- regval <<= (INT_REGISTER_SIZE - partial_len) * 8;
- if (arm_debug)
- fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n",
- argnum,
- gdbarch_register_name
- (gdbarch, argreg),
- phex (regval, INT_REGISTER_SIZE));
- regcache_cooked_write_unsigned (regcache, argreg, regval);
- argreg++;
+ offset |= (*entry & 0x7f) << shift;
+ shift += 7;
}
- else
+ while (*entry++ & 0x80);
+
+ vsp += 0x204 + (offset << 2);
+ }
+ else if (insn == 0xb3)
+ {
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
+
+ /* Only registers D0..D15 are valid here. */
+ if (start + count >= 16)
+ return NULL;
+
+ /* Pop VFP double-precision registers D[start]..D[start+count]. */
+ for (i = 0; i <= count; i++)
{
- /* Push the arguments onto the stack. */
- if (arm_debug)
- fprintf_unfiltered (gdb_stdlog, "arg %d @ sp + %d\n",
- argnum, nstack);
- si = push_stack_item (si, val, INT_REGISTER_SIZE);
- nstack += INT_REGISTER_SIZE;
+ cache->saved_regs[ARM_D0_REGNUM + start + i].addr = vsp;
+ vsp += 8;
}
-
- len -= partial_len;
- val += partial_len;
+
+ /* Add an extra 4 bytes for FSTMFDX-style stack. */
+ vsp += 4;
+ }
+ else if ((insn & 0xf8) == 0xb8)
+ {
+ int count = insn & 0x7;
+ int i;
+
+ /* Pop VFP double-precision registers D[8]..D[8+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_D0_REGNUM + 8 + i].addr = vsp;
+ vsp += 8;
+ }
+
+ /* Add an extra 4 bytes for FSTMFDX-style stack. */
+ vsp += 4;
+ }
+ else if (insn == 0xc6)
+ {
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
+
+ /* Only registers WR0..WR15 are valid. */
+ if (start + count >= 16)
+ return NULL;
+
+ /* Pop iwmmx registers WR[start]..WR[start+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_WR0_REGNUM + start + i].addr = vsp;
+ vsp += 8;
+ }
+ }
+ else if (insn == 0xc7)
+ {
+ int mask = *entry++;
+ int i;
+
+ /* All-zero mask and mask >= 16 is "spare". */
+ if (mask == 0 || mask >= 16)
+ return NULL;
+
+ /* Pop iwmmx general-purpose registers WCGR0..WCGR3 under mask. */
+ for (i = 0; i < 4; i++)
+ if (mask & (1 << i))
+ {
+ cache->saved_regs[ARM_WCGR0_REGNUM + i].addr = vsp;
+ vsp += 4;
+ }
+ }
+ else if ((insn & 0xf8) == 0xc0)
+ {
+ int count = insn & 0x7;
+ int i;
+
+ /* Pop iwmmx registers WR[10]..WR[10+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_WR0_REGNUM + 10 + i].addr = vsp;
+ vsp += 8;
+ }
+ }
+ else if (insn == 0xc8)
+ {
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
+
+ /* Only registers D0..D31 are valid. */
+ if (start + count >= 16)
+ return NULL;
+
+ /* Pop VFP double-precision registers
+ D[16+start]..D[16+start+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_D0_REGNUM + 16 + start + i].addr = vsp;
+ vsp += 8;
+ }
+ }
+ else if (insn == 0xc9)
+ {
+ int start = *entry >> 4;
+ int count = (*entry++) & 0xf;
+ int i;
+
+ /* Pop VFP double-precision registers D[start]..D[start+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_D0_REGNUM + start + i].addr = vsp;
+ vsp += 8;
+ }
+ }
+ else if ((insn & 0xf8) == 0xd0)
+ {
+ int count = insn & 0x7;
+ int i;
+
+ /* Pop VFP double-precision registers D[8]..D[8+count]. */
+ for (i = 0; i <= count; i++)
+ {
+ cache->saved_regs[ARM_D0_REGNUM + 8 + i].addr = vsp;
+ vsp += 8;
+ }
+ }
+ else
+ {
+ /* Everything else is "spare". */
+ return NULL;
}
}
- /* If we have an odd number of words to push, then decrement the stack
- by one word now, so first stack argument will be dword aligned. */
- if (nstack & 4)
- sp -= 4;
- while (si)
+ /* If we restore SP from a register, assume this was the frame register.
+ Otherwise just fall back to SP as frame register. */
+ if (trad_frame_realreg_p (cache->saved_regs, ARM_SP_REGNUM))
+ cache->framereg = cache->saved_regs[ARM_SP_REGNUM].realreg;
+ else
+ cache->framereg = ARM_SP_REGNUM;
+
+ /* Determine offset to previous frame. */
+ cache->framesize
+ = vsp - get_frame_register_unsigned (this_frame, cache->framereg);
+
+ /* We already got the previous SP. */
+ cache->prev_sp = vsp;
+
+ return cache;
+}
+
+/* Unwinding via ARM exception table entries. Note that the sniffer
+ already computes a filled-in prologue cache, which is then used
+ with the same arm_prologue_this_id and arm_prologue_prev_register
+ routines also used for prologue-parsing based unwinding. */
+
+static int
+arm_exidx_unwind_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
+{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ CORE_ADDR addr_in_block, exidx_region, func_start;
+ struct arm_prologue_cache *cache;
+ gdb_byte *entry;
+
+ /* See if we have an ARM exception table entry covering this address. */
+ addr_in_block = get_frame_address_in_block (this_frame);
+ entry = arm_find_exidx_entry (addr_in_block, &exidx_region);
+ if (!entry)
+ return 0;
+
+ /* The ARM exception table does not describe unwind information
+ for arbitrary PC values, but is guaranteed to be correct only
+ at call sites. We have to decide here whether we want to use
+ ARM exception table information for this frame, or fall back
+ to using prologue parsing. (Note that if we have DWARF CFI,
+ this sniffer isn't even called -- CFI is always preferred.)
+
+ Before we make this decision, however, we check whether we
+ actually have *symbol* information for the current frame.
+ If not, prologue parsing would not work anyway, so we might
+ as well use the exception table and hope for the best. */
+ if (find_pc_partial_function (addr_in_block, NULL, &func_start, NULL))
{
- sp -= si->len;
- write_memory (sp, si->data, si->len);
- si = pop_stack_item (si);
+ int exc_valid = 0;
+
+ /* If the next frame is "normal", we are at a call site in this
+ frame, so exception information is guaranteed to be valid. */
+ if (get_next_frame (this_frame)
+ && get_frame_type (get_next_frame (this_frame)) == NORMAL_FRAME)
+ exc_valid = 1;
+
+ /* We also assume exception information is valid if we're currently
+ blocked in a system call. The system library is supposed to
+ ensure this, so that e.g. pthread cancellation works. */
+ if (arm_frame_is_thumb (this_frame))
+ {
+ LONGEST insn;
+
+ if (safe_read_memory_integer (get_frame_pc (this_frame) - 2, 2,
+ byte_order_for_code, &insn)
+ && (insn & 0xff00) == 0xdf00 /* svc */)
+ exc_valid = 1;
+ }
+ else
+ {
+ LONGEST insn;
+
+ if (safe_read_memory_integer (get_frame_pc (this_frame) - 4, 4,
+ byte_order_for_code, &insn)
+ && (insn & 0x0f000000) == 0x0f000000 /* svc */)
+ exc_valid = 1;
+ }
+
+ /* Bail out if we don't know that exception information is valid. */
+ if (!exc_valid)
+ return 0;
+
+ /* The ARM exception index does not mark the *end* of the region
+ covered by the entry, and some functions will not have any entry.
+ To correctly recognize the end of the covered region, the linker
+ should have inserted dummy records with a CANTUNWIND marker.
+
+ Unfortunately, current versions of GNU ld do not reliably do
+ this, and thus we may have found an incorrect entry above.
+ As a (temporary) sanity check, we only use the entry if it
+ lies *within* the bounds of the function. Note that this check
+ might reject perfectly valid entries that just happen to cover
+ multiple functions; therefore this check ought to be removed
+ once the linker is fixed. */
+ if (func_start > exidx_region)
+ return 0;
}
- /* Finally, update teh SP register. */
- regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp);
+ /* Decode the list of unwinding instructions into a prologue cache.
+ Note that this may fail due to e.g. a "refuse to unwind" code. */
+ cache = arm_exidx_fill_cache (this_frame, entry);
+ if (!cache)
+ return 0;
- return sp;
+ *this_prologue_cache = cache;
+ return 1;
+}
+
+struct frame_unwind arm_exidx_unwind = {
+ NORMAL_FRAME,
+ arm_prologue_this_id,
+ arm_prologue_prev_register,
+ NULL,
+ arm_exidx_unwind_sniffer
+};
+
+static struct arm_prologue_cache *
+arm_make_stub_cache (struct frame_info *this_frame)
+{
+ struct arm_prologue_cache *cache;
+
+ cache = FRAME_OBSTACK_ZALLOC (struct arm_prologue_cache);
+ cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
+
+ cache->prev_sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM);
+
+ return cache;
+}
+
+/* Our frame ID for a stub frame is the current SP and LR. */
+
+static void
+arm_stub_this_id (struct frame_info *this_frame,
+ void **this_cache,
+ struct frame_id *this_id)
+{
+ struct arm_prologue_cache *cache;
+
+ if (*this_cache == NULL)
+ *this_cache = arm_make_stub_cache (this_frame);
+ cache = *this_cache;
+
+ *this_id = frame_id_build (cache->prev_sp, get_frame_pc (this_frame));
+}
+
+static int
+arm_stub_unwind_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
+{
+ CORE_ADDR addr_in_block;
+ char dummy[4];
+
+ addr_in_block = get_frame_address_in_block (this_frame);
+ if (in_plt_section (addr_in_block, NULL)
+ /* We also use the stub winder if the target memory is unreadable
+ to avoid having the prologue unwinder trying to read it. */
+ || target_read_memory (get_frame_pc (this_frame), dummy, 4) != 0)
+ return 1;
+
+ return 0;
+}
+
+struct frame_unwind arm_stub_unwind = {
+ NORMAL_FRAME,
+ arm_stub_this_id,
+ arm_prologue_prev_register,
+ NULL,
+ arm_stub_unwind_sniffer
+};
+
+static CORE_ADDR
+arm_normal_frame_base (struct frame_info *this_frame, void **this_cache)
+{
+ struct arm_prologue_cache *cache;
+
+ if (*this_cache == NULL)
+ *this_cache = arm_make_prologue_cache (this_frame);
+ cache = *this_cache;
+
+ return cache->prev_sp - cache->framesize;
+}
+
+struct frame_base arm_normal_base = {
+ &arm_prologue_unwind,
+ arm_normal_frame_base,
+ arm_normal_frame_base,
+ arm_normal_frame_base
+};
+
+/* Assuming THIS_FRAME is a dummy, return the frame ID of that
+ dummy frame. The frame ID's base needs to match the TOS value
+ saved by save_dummy_frame_tos() and returned from
+ arm_push_dummy_call, and the PC needs to match the dummy frame's
+ breakpoint. */
+
+static struct frame_id
+arm_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+ return frame_id_build (get_frame_register_unsigned (this_frame,
+ ARM_SP_REGNUM),
+ get_frame_pc (this_frame));
+}
+
+/* Given THIS_FRAME, find the previous frame's resume PC (which will
+ be used to construct the previous frame's ID, after looking up the
+ containing function). */
+
+static CORE_ADDR
+arm_unwind_pc (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+ CORE_ADDR pc;
+ pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM);
+ return arm_addr_bits_remove (gdbarch, pc);
+}
+
+static CORE_ADDR
+arm_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+ return frame_unwind_register_unsigned (this_frame, ARM_SP_REGNUM);
+}
+
+static struct value *
+arm_dwarf2_prev_register (struct frame_info *this_frame, void **this_cache,
+ int regnum)
+{
+ struct gdbarch * gdbarch = get_frame_arch (this_frame);
+ CORE_ADDR lr, cpsr;
+ ULONGEST t_bit = arm_psr_thumb_bit (gdbarch);
+
+ switch (regnum)
+ {
+ case ARM_PC_REGNUM:
+ /* The PC is normally copied from the return column, which
+ describes saves of LR. However, that version may have an
+ extra bit set to indicate Thumb state. The bit is not
+ part of the PC. */
+ lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
+ return frame_unwind_got_constant (this_frame, regnum,
+ arm_addr_bits_remove (gdbarch, lr));
+
+ case ARM_PS_REGNUM:
+ /* Reconstruct the T bit; see arm_prologue_prev_register for details. */
+ cpsr = get_frame_register_unsigned (this_frame, regnum);
+ lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
+ if (IS_THUMB_ADDR (lr))
+ cpsr |= t_bit;
+ else
+ cpsr &= ~t_bit;
+ return frame_unwind_got_constant (this_frame, regnum, cpsr);
+
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("Unexpected register %d"), regnum);
+ }
+}
+
+static void
+arm_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
+ struct dwarf2_frame_state_reg *reg,
+ struct frame_info *this_frame)
+{
+ switch (regnum)
+ {
+ case ARM_PC_REGNUM:
+ case ARM_PS_REGNUM:
+ reg->how = DWARF2_FRAME_REG_FN;
+ reg->loc.fn = arm_dwarf2_prev_register;
+ break;
+ case ARM_SP_REGNUM:
+ reg->how = DWARF2_FRAME_REG_CFA;
+ break;
+ }
+}
+
+/* Return true if we are in the function's epilogue, i.e. after the
+ instruction that destroyed the function's stack frame. */
+
+static int
+thumb_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned int insn, insn2;
+ int found_return = 0, found_stack_adjust = 0;
+ CORE_ADDR func_start, func_end;
+ CORE_ADDR scan_pc;
+ gdb_byte buf[4];
+
+ if (!find_pc_partial_function (pc, NULL, &func_start, &func_end))
+ return 0;
+
+ /* The epilogue is a sequence of instructions along the following lines:
+
+ - add stack frame size to SP or FP
+ - [if frame pointer used] restore SP from FP
+ - restore registers from SP [may include PC]
+ - a return-type instruction [if PC wasn't already restored]
+
+ In a first pass, we scan forward from the current PC and verify the
+ instructions we find as compatible with this sequence, ending in a
+ return instruction.
+
+ However, this is not sufficient to distinguish indirect function calls
+ within a function from indirect tail calls in the epilogue in some cases.
+ Therefore, if we didn't already find any SP-changing instruction during
+ forward scan, we add a backward scanning heuristic to ensure we actually
+ are in the epilogue. */
+
+ scan_pc = pc;
+ while (scan_pc < func_end && !found_return)
+ {
+ if (target_read_memory (scan_pc, buf, 2))
+ break;
+
+ scan_pc += 2;
+ insn = extract_unsigned_integer (buf, 2, byte_order_for_code);
+
+ if ((insn & 0xff80) == 0x4700) /* bx <Rm> */
+ found_return = 1;
+ else if (insn == 0x46f7) /* mov pc, lr */
+ found_return = 1;
+ else if (insn == 0x46bd) /* mov sp, r7 */
+ found_stack_adjust = 1;
+ else if ((insn & 0xff00) == 0xb000) /* add sp, imm or sub sp, imm */
+ found_stack_adjust = 1;
+ else if ((insn & 0xfe00) == 0xbc00) /* pop <registers> */
+ {
+ found_stack_adjust = 1;
+ if (insn & 0x0100) /* <registers> include PC. */
+ found_return = 1;
+ }
+ else if ((insn & 0xe000) == 0xe000) /* 32-bit Thumb-2 instruction */
+ {
+ if (target_read_memory (scan_pc, buf, 2))
+ break;
+
+ scan_pc += 2;
+ insn2 = extract_unsigned_integer (buf, 2, byte_order_for_code);
+
+ if (insn == 0xe8bd) /* ldm.w sp!, <registers> */
+ {
+ found_stack_adjust = 1;
+ if (insn2 & 0x8000) /* <registers> include PC. */
+ found_return = 1;
+ }
+ else if (insn == 0xf85d /* ldr.w <Rt>, [sp], #4 */
+ && (insn2 & 0x0fff) == 0x0b04)
+ {
+ found_stack_adjust = 1;
+ if ((insn2 & 0xf000) == 0xf000) /* <Rt> is PC. */
+ found_return = 1;
+ }
+ else if ((insn & 0xffbf) == 0xecbd /* vldm sp!, <list> */
+ && (insn2 & 0x0e00) == 0x0a00)
+ found_stack_adjust = 1;
+ else
+ break;
+ }
+ else
+ break;
+ }
+
+ if (!found_return)
+ return 0;
+
+ /* Since any instruction in the epilogue sequence, with the possible
+ exception of return itself, updates the stack pointer, we need to
+ scan backwards for at most one instruction. Try either a 16-bit or
+ a 32-bit instruction. This is just a heuristic, so we do not worry
+ too much about false positives. */
+
+ if (!found_stack_adjust)
+ {
+ if (pc - 4 < func_start)
+ return 0;
+ if (target_read_memory (pc - 4, buf, 4))
+ return 0;
+
+ insn = extract_unsigned_integer (buf, 2, byte_order_for_code);
+ insn2 = extract_unsigned_integer (buf + 2, 2, byte_order_for_code);
+
+ if (insn2 == 0x46bd) /* mov sp, r7 */
+ found_stack_adjust = 1;
+ else if ((insn2 & 0xff00) == 0xb000) /* add sp, imm or sub sp, imm */
+ found_stack_adjust = 1;
+ else if ((insn2 & 0xff00) == 0xbc00) /* pop <registers> without PC */
+ found_stack_adjust = 1;
+ else if (insn == 0xe8bd) /* ldm.w sp!, <registers> */
+ found_stack_adjust = 1;
+ else if (insn == 0xf85d /* ldr.w <Rt>, [sp], #4 */
+ && (insn2 & 0x0fff) == 0x0b04)
+ found_stack_adjust = 1;
+ else if ((insn & 0xffbf) == 0xecbd /* vldm sp!, <list> */
+ && (insn2 & 0x0e00) == 0x0a00)
+ found_stack_adjust = 1;
+ }
+
+ return found_stack_adjust;
}
+/* Return true if we are in the function's epilogue, i.e. after the
+ instruction that destroyed the function's stack frame. */
+
+static int
+arm_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned int insn;
+ int found_return, found_stack_adjust;
+ CORE_ADDR func_start, func_end;
+
+ if (arm_pc_is_thumb (gdbarch, pc))
+ return thumb_in_function_epilogue_p (gdbarch, pc);
+
+ if (!find_pc_partial_function (pc, NULL, &func_start, &func_end))
+ return 0;
+
+ /* We are in the epilogue if the previous instruction was a stack
+ adjustment and the next instruction is a possible return (bx, mov
+ pc, or pop). We could have to scan backwards to find the stack
+ adjustment, or forwards to find the return, but this is a decent
+ approximation. First scan forwards. */
+
+ found_return = 0;
+ insn = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+ if (bits (insn, 28, 31) != INST_NV)
+ {
+ if ((insn & 0x0ffffff0) == 0x012fff10)
+ /* BX. */
+ found_return = 1;
+ else if ((insn & 0x0ffffff0) == 0x01a0f000)
+ /* MOV PC. */
+ found_return = 1;
+ else if ((insn & 0x0fff0000) == 0x08bd0000
+ && (insn & 0x0000c000) != 0)
+ /* POP (LDMIA), including PC or LR. */
+ found_return = 1;
+ }
+
+ if (!found_return)
+ return 0;
+
+ /* Scan backwards. This is just a heuristic, so do not worry about
+ false positives from mode changes. */
+
+ if (pc < func_start + 4)
+ return 0;
+
+ found_stack_adjust = 0;
+ insn = read_memory_unsigned_integer (pc - 4, 4, byte_order_for_code);
+ if (bits (insn, 28, 31) != INST_NV)
+ {
+ if ((insn & 0x0df0f000) == 0x0080d000)
+ /* ADD SP (register or immediate). */
+ found_stack_adjust = 1;
+ else if ((insn & 0x0df0f000) == 0x0040d000)
+ /* SUB SP (register or immediate). */
+ found_stack_adjust = 1;
+ else if ((insn & 0x0ffffff0) == 0x01a0d000)
+ /* MOV SP. */
+ found_stack_adjust = 1;
+ else if ((insn & 0x0fff0000) == 0x08bd0000)
+ /* POP (LDMIA). */
+ found_stack_adjust = 1;
+ }
+
+ if (found_stack_adjust)
+ return 1;
+
+ return 0;
+}
+
+
+/* When arguments must be pushed onto the stack, they go on in reverse
+ order. The code below implements a FILO (stack) to do this. */
+
+struct stack_item
+{
+ int len;
+ struct stack_item *prev;
+ void *data;
+};
+
+static struct stack_item *
+push_stack_item (struct stack_item *prev, const void *contents, int len)
+{
+ struct stack_item *si;
+ si = xmalloc (sizeof (struct stack_item));
+ si->data = xmalloc (len);
+ si->len = len;
+ si->prev = prev;
+ memcpy (si->data, contents, len);
+ return si;
+}
+
+static struct stack_item *
+pop_stack_item (struct stack_item *si)
+{
+ struct stack_item *dead = si;
+ si = si->prev;
+ xfree (dead->data);
+ xfree (dead);
+ return si;
+}
+
+
+/* Return the alignment (in bytes) of the given type. */
+
+static int
+arm_type_align (struct type *t)
+{
+ int n;
+ int align;
+ int falign;
+
+ t = check_typedef (t);
+ switch (TYPE_CODE (t))
+ {
+ default:
+ /* Should never happen. */
+ internal_error (__FILE__, __LINE__, _("unknown type alignment"));
+ return 4;
+
+ case TYPE_CODE_PTR:
+ case TYPE_CODE_ENUM:
+ case TYPE_CODE_INT:
+ case TYPE_CODE_FLT:
+ case TYPE_CODE_SET:
+ case TYPE_CODE_RANGE:
+ case TYPE_CODE_BITSTRING:
+ case TYPE_CODE_REF:
+ case TYPE_CODE_CHAR:
+ case TYPE_CODE_BOOL:
+ return TYPE_LENGTH (t);
+
+ case TYPE_CODE_ARRAY:
+ case TYPE_CODE_COMPLEX:
+ /* TODO: What about vector types? */
+ return arm_type_align (TYPE_TARGET_TYPE (t));
+
+ case TYPE_CODE_STRUCT:
+ case TYPE_CODE_UNION:
+ align = 1;
+ for (n = 0; n < TYPE_NFIELDS (t); n++)
+ {
+ falign = arm_type_align (TYPE_FIELD_TYPE (t, n));
+ if (falign > align)
+ align = falign;
+ }
+ return align;
+ }
+}
+
+/* Possible base types for a candidate for passing and returning in
+ VFP registers. */
+
+enum arm_vfp_cprc_base_type
+{
+ VFP_CPRC_UNKNOWN,
+ VFP_CPRC_SINGLE,
+ VFP_CPRC_DOUBLE,
+ VFP_CPRC_VEC64,
+ VFP_CPRC_VEC128
+};
+
+/* The length of one element of base type B. */
+
+static unsigned
+arm_vfp_cprc_unit_length (enum arm_vfp_cprc_base_type b)
+{
+ switch (b)
+ {
+ case VFP_CPRC_SINGLE:
+ return 4;
+ case VFP_CPRC_DOUBLE:
+ return 8;
+ case VFP_CPRC_VEC64:
+ return 8;
+ case VFP_CPRC_VEC128:
+ return 16;
+ default:
+ internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
+ (int) b);
+ }
+}
+
+/* The character ('s', 'd' or 'q') for the type of VFP register used
+ for passing base type B. */
+
+static int
+arm_vfp_cprc_reg_char (enum arm_vfp_cprc_base_type b)
+{
+ switch (b)
+ {
+ case VFP_CPRC_SINGLE:
+ return 's';
+ case VFP_CPRC_DOUBLE:
+ return 'd';
+ case VFP_CPRC_VEC64:
+ return 'd';
+ case VFP_CPRC_VEC128:
+ return 'q';
+ default:
+ internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
+ (int) b);
+ }
+}
+
+/* Determine whether T may be part of a candidate for passing and
+ returning in VFP registers, ignoring the limit on the total number
+ of components. If *BASE_TYPE is VFP_CPRC_UNKNOWN, set it to the
+ classification of the first valid component found; if it is not
+ VFP_CPRC_UNKNOWN, all components must have the same classification
+ as *BASE_TYPE. If it is found that T contains a type not permitted
+ for passing and returning in VFP registers, a type differently
+ classified from *BASE_TYPE, or two types differently classified
+ from each other, return -1, otherwise return the total number of
+ base-type elements found (possibly 0 in an empty structure or
+ array). Vectors and complex types are not currently supported,
+ matching the generic AAPCS support. */
+
+static int
+arm_vfp_cprc_sub_candidate (struct type *t,
+ enum arm_vfp_cprc_base_type *base_type)
+{
+ t = check_typedef (t);
+ switch (TYPE_CODE (t))
+ {
+ case TYPE_CODE_FLT:
+ switch (TYPE_LENGTH (t))
+ {
+ case 4:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_SINGLE;
+ else if (*base_type != VFP_CPRC_SINGLE)
+ return -1;
+ return 1;
+
+ case 8:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_DOUBLE;
+ else if (*base_type != VFP_CPRC_DOUBLE)
+ return -1;
+ return 1;
+
+ default:
+ return -1;
+ }
+ break;
+
+ case TYPE_CODE_ARRAY:
+ {
+ int count;
+ unsigned unitlen;
+ count = arm_vfp_cprc_sub_candidate (TYPE_TARGET_TYPE (t), base_type);
+ if (count == -1)
+ return -1;
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ gdb_assert ((TYPE_LENGTH (t) % unitlen) == 0);
+ return TYPE_LENGTH (t) / unitlen;
+ }
+ break;
+
+ case TYPE_CODE_STRUCT:
+ {
+ int count = 0;
+ unsigned unitlen;
+ int i;
+ for (i = 0; i < TYPE_NFIELDS (t); i++)
+ {
+ int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
+ base_type);
+ if (sub_count == -1)
+ return -1;
+ count += sub_count;
+ }
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ if (TYPE_LENGTH (t) != unitlen * count)
+ return -1;
+ return count;
+ }
+
+ case TYPE_CODE_UNION:
+ {
+ int count = 0;
+ unsigned unitlen;
+ int i;
+ for (i = 0; i < TYPE_NFIELDS (t); i++)
+ {
+ int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
+ base_type);
+ if (sub_count == -1)
+ return -1;
+ count = (count > sub_count ? count : sub_count);
+ }
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ if (TYPE_LENGTH (t) != unitlen * count)
+ return -1;
+ return count;
+ }
+
+ default:
+ break;
+ }
+
+ return -1;
+}
+
+/* Determine whether T is a VFP co-processor register candidate (CPRC)
+ if passed to or returned from a non-variadic function with the VFP
+ ABI in effect. Return 1 if it is, 0 otherwise. If it is, set
+ *BASE_TYPE to the base type for T and *COUNT to the number of
+ elements of that base type before returning. */
+
+static int
+arm_vfp_call_candidate (struct type *t, enum arm_vfp_cprc_base_type *base_type,
+ int *count)
+{
+ enum arm_vfp_cprc_base_type b = VFP_CPRC_UNKNOWN;
+ int c = arm_vfp_cprc_sub_candidate (t, &b);
+ if (c <= 0 || c > 4)
+ return 0;
+ *base_type = b;
+ *count = c;
+ return 1;
+}
+
+/* Return 1 if the VFP ABI should be used for passing arguments to and
+ returning values from a function of type FUNC_TYPE, 0
+ otherwise. */
+
+static int
+arm_vfp_abi_for_function (struct gdbarch *gdbarch, struct type *func_type)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ /* Variadic functions always use the base ABI. Assume that functions
+ without debug info are not variadic. */
+ if (func_type && TYPE_VARARGS (check_typedef (func_type)))
+ return 0;
+ /* The VFP ABI is only supported as a variant of AAPCS. */
+ if (tdep->arm_abi != ARM_ABI_AAPCS)
+ return 0;
+ return gdbarch_tdep (gdbarch)->fp_model == ARM_FLOAT_VFP;
+}
+
+/* We currently only support passing parameters in integer registers, which
+ conforms with GCC's default model, and VFP argument passing following
+ the VFP variant of AAPCS. Several other variants exist and
+ we should probably support some of them based on the selected ABI. */
+
+static CORE_ADDR
+arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
+ struct regcache *regcache, CORE_ADDR bp_addr, int nargs,
+ struct value **args, CORE_ADDR sp, int struct_return,
+ CORE_ADDR struct_addr)
+{
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int argnum;
+ int argreg;
+ int nstack;
+ struct stack_item *si = NULL;
+ int use_vfp_abi;
+ struct type *ftype;
+ unsigned vfp_regs_free = (1 << 16) - 1;
+
+ /* Determine the type of this function and whether the VFP ABI
+ applies. */
+ ftype = check_typedef (value_type (function));
+ if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
+ ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
+ use_vfp_abi = arm_vfp_abi_for_function (gdbarch, ftype);
+
+ /* Set the return address. For the ARM, the return breakpoint is
+ always at BP_ADDR. */
+ if (arm_pc_is_thumb (gdbarch, bp_addr))
+ bp_addr |= 1;
+ regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr);
+
+ /* Walk through the list of args and determine how large a temporary
+ stack is required. Need to take care here as structs may be
+ passed on the stack, and we have to to push them. */
+ nstack = 0;
+
+ argreg = ARM_A1_REGNUM;
+ nstack = 0;
+
+ /* The struct_return pointer occupies the first parameter
+ passing register. */
+ if (struct_return)
+ {
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "struct return in %s = %s\n",
+ gdbarch_register_name (gdbarch, argreg),
+ paddress (gdbarch, struct_addr));
+ regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
+ argreg++;
+ }
+
+ for (argnum = 0; argnum < nargs; argnum++)
+ {
+ int len;
+ struct type *arg_type;
+ struct type *target_type;
+ enum type_code typecode;
+ const bfd_byte *val;
+ int align;
+ enum arm_vfp_cprc_base_type vfp_base_type;
+ int vfp_base_count;
+ int may_use_core_reg = 1;
+
+ arg_type = check_typedef (value_type (args[argnum]));
+ len = TYPE_LENGTH (arg_type);
+ target_type = TYPE_TARGET_TYPE (arg_type);
+ typecode = TYPE_CODE (arg_type);
+ val = value_contents (args[argnum]);
+
+ align = arm_type_align (arg_type);
+ /* Round alignment up to a whole number of words. */
+ align = (align + INT_REGISTER_SIZE - 1) & ~(INT_REGISTER_SIZE - 1);
+ /* Different ABIs have different maximum alignments. */
+ if (gdbarch_tdep (gdbarch)->arm_abi == ARM_ABI_APCS)
+ {
+ /* The APCS ABI only requires word alignment. */
+ align = INT_REGISTER_SIZE;
+ }
+ else
+ {
+ /* The AAPCS requires at most doubleword alignment. */
+ if (align > INT_REGISTER_SIZE * 2)
+ align = INT_REGISTER_SIZE * 2;
+ }
+
+ if (use_vfp_abi
+ && arm_vfp_call_candidate (arg_type, &vfp_base_type,
+ &vfp_base_count))
+ {
+ int regno;
+ int unit_length;
+ int shift;
+ unsigned mask;
+
+ /* Because this is a CPRC it cannot go in a core register or
+ cause a core register to be skipped for alignment.
+ Either it goes in VFP registers and the rest of this loop
+ iteration is skipped for this argument, or it goes on the
+ stack (and the stack alignment code is correct for this
+ case). */
+ may_use_core_reg = 0;
+
+ unit_length = arm_vfp_cprc_unit_length (vfp_base_type);
+ shift = unit_length / 4;
+ mask = (1 << (shift * vfp_base_count)) - 1;
+ for (regno = 0; regno < 16; regno += shift)
+ if (((vfp_regs_free >> regno) & mask) == mask)
+ break;
+
+ if (regno < 16)
+ {
+ int reg_char;
+ int reg_scaled;
+ int i;
+
+ vfp_regs_free &= ~(mask << regno);
+ reg_scaled = regno / shift;
+ reg_char = arm_vfp_cprc_reg_char (vfp_base_type);
+ for (i = 0; i < vfp_base_count; i++)
+ {
+ char name_buf[4];
+ int regnum;
+ if (reg_char == 'q')
+ arm_neon_quad_write (gdbarch, regcache, reg_scaled + i,
+ val + i * unit_length);
+ else
+ {
+ sprintf (name_buf, "%c%d", reg_char, reg_scaled + i);
+ regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ regcache_cooked_write (regcache, regnum,
+ val + i * unit_length);
+ }
+ }
+ continue;
+ }
+ else
+ {
+ /* This CPRC could not go in VFP registers, so all VFP
+ registers are now marked as used. */
+ vfp_regs_free = 0;
+ }
+ }
+
+ /* Push stack padding for dowubleword alignment. */
+ if (nstack & (align - 1))
+ {
+ si = push_stack_item (si, val, INT_REGISTER_SIZE);
+ nstack += INT_REGISTER_SIZE;
+ }
+
+ /* Doubleword aligned quantities must go in even register pairs. */
+ if (may_use_core_reg
+ && argreg <= ARM_LAST_ARG_REGNUM
+ && align > INT_REGISTER_SIZE
+ && argreg & 1)
+ argreg++;
+
+ /* If the argument is a pointer to a function, and it is a
+ Thumb function, create a LOCAL copy of the value and set
+ the THUMB bit in it. */
+ if (TYPE_CODE_PTR == typecode
+ && target_type != NULL
+ && TYPE_CODE_FUNC == TYPE_CODE (check_typedef (target_type)))
+ {
+ CORE_ADDR regval = extract_unsigned_integer (val, len, byte_order);
+ if (arm_pc_is_thumb (gdbarch, regval))
+ {
+ bfd_byte *copy = alloca (len);
+ store_unsigned_integer (copy, len, byte_order,
+ MAKE_THUMB_ADDR (regval));
+ val = copy;
+ }
+ }
+
+ /* Copy the argument to general registers or the stack in
+ register-sized pieces. Large arguments are split between
+ registers and stack. */
+ while (len > 0)
+ {
+ int partial_len = len < INT_REGISTER_SIZE ? len : INT_REGISTER_SIZE;
+
+ if (may_use_core_reg && argreg <= ARM_LAST_ARG_REGNUM)
+ {
+ /* The argument is being passed in a general purpose
+ register. */
+ CORE_ADDR regval
+ = extract_unsigned_integer (val, partial_len, byte_order);
+ if (byte_order == BFD_ENDIAN_BIG)
+ regval <<= (INT_REGISTER_SIZE - partial_len) * 8;
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n",
+ argnum,
+ gdbarch_register_name
+ (gdbarch, argreg),
+ phex (regval, INT_REGISTER_SIZE));
+ regcache_cooked_write_unsigned (regcache, argreg, regval);
+ argreg++;
+ }
+ else
+ {
+ /* Push the arguments onto the stack. */
+ if (arm_debug)
+ fprintf_unfiltered (gdb_stdlog, "arg %d @ sp + %d\n",
+ argnum, nstack);
+ si = push_stack_item (si, val, INT_REGISTER_SIZE);
+ nstack += INT_REGISTER_SIZE;
+ }
+
+ len -= partial_len;
+ val += partial_len;
+ }
+ }
+ /* If we have an odd number of words to push, then decrement the stack
+ by one word now, so first stack argument will be dword aligned. */
+ if (nstack & 4)
+ sp -= 4;
+
+ while (si)
+ {
+ sp -= si->len;
+ write_memory (sp, si->data, si->len);
+ si = pop_stack_item (si);
+ }
+
+ /* Finally, update teh SP register. */
+ regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp);
+
+ return sp;
+}
+
+
+/* Always align the frame to an 8-byte boundary. This is required on
+ some platforms and harmless on the rest. */
+
+static CORE_ADDR
+arm_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
+{
+ /* Align the stack to eight bytes. */
+ return sp & ~ (CORE_ADDR) 7;
+}
+
+static void
+print_fpu_flags (int flags)
+{
+ if (flags & (1 << 0))
+ fputs ("IVO ", stdout);
+ if (flags & (1 << 1))
+ fputs ("DVZ ", stdout);
+ if (flags & (1 << 2))
+ fputs ("OFL ", stdout);
+ if (flags & (1 << 3))
+ fputs ("UFL ", stdout);
+ if (flags & (1 << 4))
+ fputs ("INX ", stdout);
+ putchar ('\n');
+}
+
+/* Print interesting information about the floating point processor
+ (if present) or emulator. */
+static void
+arm_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
+ struct frame_info *frame, const char *args)
+{
+ unsigned long status = get_frame_register_unsigned (frame, ARM_FPS_REGNUM);
+ int type;
+
+ type = (status >> 24) & 127;
+ if (status & (1 << 31))
+ printf (_("Hardware FPU type %d\n"), type);
+ else
+ printf (_("Software FPU type %d\n"), type);
+ /* i18n: [floating point unit] mask */
+ fputs (_("mask: "), stdout);
+ print_fpu_flags (status >> 16);
+ /* i18n: [floating point unit] flags */
+ fputs (_("flags: "), stdout);
+ print_fpu_flags (status);
+}
+
+/* Construct the ARM extended floating point type. */
+static struct type *
+arm_ext_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (!tdep->arm_ext_type)
+ tdep->arm_ext_type
+ = arch_float_type (gdbarch, -1, "builtin_type_arm_ext",
+ floatformats_arm_ext);
+
+ return tdep->arm_ext_type;
+}
+
+static struct type *
+arm_neon_double_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->neon_double_type == NULL)
+ {
+ struct type *t, *elem;
+
+ t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_d",
+ TYPE_CODE_UNION);
+ elem = builtin_type (gdbarch)->builtin_uint8;
+ append_composite_type_field (t, "u8", init_vector_type (elem, 8));
+ elem = builtin_type (gdbarch)->builtin_uint16;
+ append_composite_type_field (t, "u16", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_uint32;
+ append_composite_type_field (t, "u32", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_uint64;
+ append_composite_type_field (t, "u64", elem);
+ elem = builtin_type (gdbarch)->builtin_float;
+ append_composite_type_field (t, "f32", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_double;
+ append_composite_type_field (t, "f64", elem);
+
+ TYPE_VECTOR (t) = 1;
+ TYPE_NAME (t) = "neon_d";
+ tdep->neon_double_type = t;
+ }
+
+ return tdep->neon_double_type;
+}
+
+/* FIXME: The vector types are not correctly ordered on big-endian
+ targets. Just as s0 is the low bits of d0, d0[0] is also the low
+ bits of d0 - regardless of what unit size is being held in d0. So
+ the offset of the first uint8 in d0 is 7, but the offset of the
+ first float is 4. This code works as-is for little-endian
+ targets. */
+
+static struct type *
+arm_neon_quad_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->neon_quad_type == NULL)
+ {
+ struct type *t, *elem;
+
+ t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_q",
+ TYPE_CODE_UNION);
+ elem = builtin_type (gdbarch)->builtin_uint8;
+ append_composite_type_field (t, "u8", init_vector_type (elem, 16));
+ elem = builtin_type (gdbarch)->builtin_uint16;
+ append_composite_type_field (t, "u16", init_vector_type (elem, 8));
+ elem = builtin_type (gdbarch)->builtin_uint32;
+ append_composite_type_field (t, "u32", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_uint64;
+ append_composite_type_field (t, "u64", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_float;
+ append_composite_type_field (t, "f32", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_double;
+ append_composite_type_field (t, "f64", init_vector_type (elem, 2));
+
+ TYPE_VECTOR (t) = 1;
+ TYPE_NAME (t) = "neon_q";
+ tdep->neon_quad_type = t;
+ }
+
+ return tdep->neon_quad_type;
+}
+
+/* Return the GDB type object for the "standard" data type of data in
+ register N. */
+
+static struct type *
+arm_register_type (struct gdbarch *gdbarch, int regnum)
+{
+ int num_regs = gdbarch_num_regs (gdbarch);
+
+ if (gdbarch_tdep (gdbarch)->have_vfp_pseudos
+ && regnum >= num_regs && regnum < num_regs + 32)
+ return builtin_type (gdbarch)->builtin_float;
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos
+ && regnum >= num_regs + 32 && regnum < num_regs + 32 + 16)
+ return arm_neon_quad_type (gdbarch);
+
+ /* If the target description has register information, we are only
+ in this function so that we can override the types of
+ double-precision registers for NEON. */
+ if (tdesc_has_registers (gdbarch_target_desc (gdbarch)))
+ {
+ struct type *t = tdesc_register_type (gdbarch, regnum);
+
+ if (regnum >= ARM_D0_REGNUM && regnum < ARM_D0_REGNUM + 32
+ && TYPE_CODE (t) == TYPE_CODE_FLT
+ && gdbarch_tdep (gdbarch)->have_neon)
+ return arm_neon_double_type (gdbarch);
+ else
+ return t;
+ }
+
+ if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS)
+ {
+ if (!gdbarch_tdep (gdbarch)->have_fpa_registers)
+ return builtin_type (gdbarch)->builtin_void;
+
+ return arm_ext_type (gdbarch);
+ }
+ else if (regnum == ARM_SP_REGNUM)
+ return builtin_type (gdbarch)->builtin_data_ptr;
+ else if (regnum == ARM_PC_REGNUM)
+ return builtin_type (gdbarch)->builtin_func_ptr;
+ else if (regnum >= ARRAY_SIZE (arm_register_names))
+ /* These registers are only supported on targets which supply
+ an XML description. */
+ return builtin_type (gdbarch)->builtin_int0;
+ else
+ return builtin_type (gdbarch)->builtin_uint32;
+}
+
+/* Map a DWARF register REGNUM onto the appropriate GDB register
+ number. */
+
+static int
+arm_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
+{
+ /* Core integer regs. */
+ if (reg >= 0 && reg <= 15)
+ return reg;
+
+ /* Legacy FPA encoding. These were once used in a way which
+ overlapped with VFP register numbering, so their use is
+ discouraged, but GDB doesn't support the ARM toolchain
+ which used them for VFP. */
+ if (reg >= 16 && reg <= 23)
+ return ARM_F0_REGNUM + reg - 16;
+
+ /* New assignments for the FPA registers. */
+ if (reg >= 96 && reg <= 103)
+ return ARM_F0_REGNUM + reg - 96;
+
+ /* WMMX register assignments. */
+ if (reg >= 104 && reg <= 111)
+ return ARM_WCGR0_REGNUM + reg - 104;
+
+ if (reg >= 112 && reg <= 127)
+ return ARM_WR0_REGNUM + reg - 112;
+
+ if (reg >= 192 && reg <= 199)
+ return ARM_WC0_REGNUM + reg - 192;
+
+ /* VFP v2 registers. A double precision value is actually
+ in d1 rather than s2, but the ABI only defines numbering
+ for the single precision registers. This will "just work"
+ in GDB for little endian targets (we'll read eight bytes,
+ starting in s0 and then progressing to s1), but will be
+ reversed on big endian targets with VFP. This won't
+ be a problem for the new Neon quad registers; you're supposed
+ to use DW_OP_piece for those. */
+ if (reg >= 64 && reg <= 95)
+ {
+ char name_buf[4];
+
+ sprintf (name_buf, "s%d", reg - 64);
+ return user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ }
+
+ /* VFP v3 / Neon registers. This range is also used for VFP v2
+ registers, except that it now describes d0 instead of s0. */
+ if (reg >= 256 && reg <= 287)
+ {
+ char name_buf[4];
+
+ sprintf (name_buf, "d%d", reg - 256);
+ return user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ }
+
+ return -1;
+}
+
+/* Map GDB internal REGNUM onto the Arm simulator register numbers. */
+static int
+arm_register_sim_regno (struct gdbarch *gdbarch, int regnum)
+{
+ int reg = regnum;
+ gdb_assert (reg >= 0 && reg < gdbarch_num_regs (gdbarch));
+
+ if (regnum >= ARM_WR0_REGNUM && regnum <= ARM_WR15_REGNUM)
+ return regnum - ARM_WR0_REGNUM + SIM_ARM_IWMMXT_COP0R0_REGNUM;
+
+ if (regnum >= ARM_WC0_REGNUM && regnum <= ARM_WC7_REGNUM)
+ return regnum - ARM_WC0_REGNUM + SIM_ARM_IWMMXT_COP1R0_REGNUM;
+
+ if (regnum >= ARM_WCGR0_REGNUM && regnum <= ARM_WCGR7_REGNUM)
+ return regnum - ARM_WCGR0_REGNUM + SIM_ARM_IWMMXT_COP1R8_REGNUM;
+
+ if (reg < NUM_GREGS)
+ return SIM_ARM_R0_REGNUM + reg;
+ reg -= NUM_GREGS;
+
+ if (reg < NUM_FREGS)
+ return SIM_ARM_FP0_REGNUM + reg;
+ reg -= NUM_FREGS;
+
+ if (reg < NUM_SREGS)
+ return SIM_ARM_FPS_REGNUM + reg;
+ reg -= NUM_SREGS;
+
+ internal_error (__FILE__, __LINE__, _("Bad REGNUM %d"), regnum);
+}
+
+/* NOTE: cagney/2001-08-20: Both convert_from_extended() and
+ convert_to_extended() use floatformat_arm_ext_littlebyte_bigword.
+ It is thought that this is is the floating-point register format on
+ little-endian systems. */
+
+static void
+convert_from_extended (const struct floatformat *fmt, const void *ptr,
+ void *dbl, int endianess)
+{
+ DOUBLEST d;
+
+ if (endianess == BFD_ENDIAN_BIG)
+ floatformat_to_doublest (&floatformat_arm_ext_big, ptr, &d);
+ else
+ floatformat_to_doublest (&floatformat_arm_ext_littlebyte_bigword,
+ ptr, &d);
+ floatformat_from_doublest (fmt, &d, dbl);
+}
+
+static void
+convert_to_extended (const struct floatformat *fmt, void *dbl, const void *ptr,
+ int endianess)
+{
+ DOUBLEST d;
+
+ floatformat_to_doublest (fmt, ptr, &d);
+ if (endianess == BFD_ENDIAN_BIG)
+ floatformat_from_doublest (&floatformat_arm_ext_big, &d, dbl);
+ else
+ floatformat_from_doublest (&floatformat_arm_ext_littlebyte_bigword,
+ &d, dbl);
+}
+
+static int
+condition_true (unsigned long cond, unsigned long status_reg)
+{
+ if (cond == INST_AL || cond == INST_NV)
+ return 1;
+
+ switch (cond)
+ {
+ case INST_EQ:
+ return ((status_reg & FLAG_Z) != 0);
+ case INST_NE:
+ return ((status_reg & FLAG_Z) == 0);
+ case INST_CS:
+ return ((status_reg & FLAG_C) != 0);
+ case INST_CC:
+ return ((status_reg & FLAG_C) == 0);
+ case INST_MI:
+ return ((status_reg & FLAG_N) != 0);
+ case INST_PL:
+ return ((status_reg & FLAG_N) == 0);
+ case INST_VS:
+ return ((status_reg & FLAG_V) != 0);
+ case INST_VC:
+ return ((status_reg & FLAG_V) == 0);
+ case INST_HI:
+ return ((status_reg & (FLAG_C | FLAG_Z)) == FLAG_C);
+ case INST_LS:
+ return ((status_reg & (FLAG_C | FLAG_Z)) != FLAG_C);
+ case INST_GE:
+ return (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0));
+ case INST_LT:
+ return (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0));
+ case INST_GT:
+ return (((status_reg & FLAG_Z) == 0)
+ && (((status_reg & FLAG_N) == 0)
+ == ((status_reg & FLAG_V) == 0)));
+ case INST_LE:
+ return (((status_reg & FLAG_Z) != 0)
+ || (((status_reg & FLAG_N) == 0)
+ != ((status_reg & FLAG_V) == 0)));
+ }
+ return 1;
+}
+
+static unsigned long
+shifted_reg_val (struct frame_info *frame, unsigned long inst, int carry,
+ unsigned long pc_val, unsigned long status_reg)
+{
+ unsigned long res, shift;
+ int rm = bits (inst, 0, 3);
+ unsigned long shifttype = bits (inst, 5, 6);
+
+ if (bit (inst, 4))
+ {
+ int rs = bits (inst, 8, 11);
+ shift = (rs == 15 ? pc_val + 8
+ : get_frame_register_unsigned (frame, rs)) & 0xFF;
+ }
+ else
+ shift = bits (inst, 7, 11);
+
+ res = (rm == ARM_PC_REGNUM
+ ? (pc_val + (bit (inst, 4) ? 12 : 8))
+ : get_frame_register_unsigned (frame, rm));
+
+ switch (shifttype)
+ {
+ case 0: /* LSL */
+ res = shift >= 32 ? 0 : res << shift;
+ break;
+
+ case 1: /* LSR */
+ res = shift >= 32 ? 0 : res >> shift;
+ break;
+
+ case 2: /* ASR */
+ if (shift >= 32)
+ shift = 31;
+ res = ((res & 0x80000000L)
+ ? ~((~res) >> shift) : res >> shift);
+ break;
+
+ case 3: /* ROR/RRX */
+ shift &= 31;
+ if (shift == 0)
+ res = (res >> 1) | (carry ? 0x80000000L : 0);
+ else
+ res = (res >> shift) | (res << (32 - shift));
+ break;
+ }
+
+ return res & 0xffffffff;
+}
+
+/* Return number of 1-bits in VAL. */
+
+static int
+bitcount (unsigned long val)
+{
+ int nbits;
+ for (nbits = 0; val != 0; nbits++)
+ val &= val - 1; /* Delete rightmost 1-bit in val. */
+ return nbits;
+}
+
+/* Return the size in bytes of the complete Thumb instruction whose
+ first halfword is INST1. */
+
+static int
+thumb_insn_size (unsigned short inst1)
+{
+ if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
+ return 4;
+ else
+ return 2;
+}
+
+static int
+thumb_advance_itstate (unsigned int itstate)
+{
+ /* Preserve IT[7:5], the first three bits of the condition. Shift
+ the upcoming condition flags left by one bit. */
+ itstate = (itstate & 0xe0) | ((itstate << 1) & 0x1f);
+
+ /* If we have finished the IT block, clear the state. */
+ if ((itstate & 0x0f) == 0)
+ itstate = 0;
+
+ return itstate;
+}
+
+/* Find the next PC after the current instruction executes. In some
+ cases we can not statically determine the answer (see the IT state
+ handling in this function); in that case, a breakpoint may be
+ inserted in addition to the returned PC, which will be used to set
+ another breakpoint by our caller. */
+
+static CORE_ADDR
+thumb_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct address_space *aspace = get_frame_address_space (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
+ unsigned short inst1;
+ CORE_ADDR nextpc = pc + 2; /* Default is next instruction. */
+ unsigned long offset;
+ ULONGEST status, itstate;
+
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ pc_val = MAKE_THUMB_ADDR (pc_val);
+
+ inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
+
+ /* Thumb-2 conditional execution support. There are eight bits in
+ the CPSR which describe conditional execution state. Once
+ reconstructed (they're in a funny order), the low five bits
+ describe the low bit of the condition for each instruction and
+ how many instructions remain. The high three bits describe the
+ base condition. One of the low four bits will be set if an IT
+ block is active. These bits read as zero on earlier
+ processors. */
+ status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
+ itstate = ((status >> 8) & 0xfc) | ((status >> 25) & 0x3);
+
+ /* If-Then handling. On GNU/Linux, where this routine is used, we
+ use an undefined instruction as a breakpoint. Unlike BKPT, IT
+ can disable execution of the undefined instruction. So we might
+ miss the breakpoint if we set it on a skipped conditional
+ instruction. Because conditional instructions can change the
+ flags, affecting the execution of further instructions, we may
+ need to set two breakpoints. */
+
+ if (gdbarch_tdep (gdbarch)->thumb2_breakpoint != NULL)
+ {
+ if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
+ {
+ /* An IT instruction. Because this instruction does not
+ modify the flags, we can accurately predict the next
+ executed instruction. */
+ itstate = inst1 & 0x00ff;
+ pc += thumb_insn_size (inst1);
+
+ while (itstate != 0 && ! condition_true (itstate >> 4, status))
+ {
+ inst1 = read_memory_unsigned_integer (pc, 2,
+ byte_order_for_code);
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+ }
+
+ return MAKE_THUMB_ADDR (pc);
+ }
+ else if (itstate != 0)
+ {
+ /* We are in a conditional block. Check the condition. */
+ if (! condition_true (itstate >> 4, status))
+ {
+ /* Advance to the next executed instruction. */
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+
+ while (itstate != 0 && ! condition_true (itstate >> 4, status))
+ {
+ inst1 = read_memory_unsigned_integer (pc, 2,
+ byte_order_for_code);
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+ }
+
+ return MAKE_THUMB_ADDR (pc);
+ }
+ else if ((itstate & 0x0f) == 0x08)
+ {
+ /* This is the last instruction of the conditional
+ block, and it is executed. We can handle it normally
+ because the following instruction is not conditional,
+ and we must handle it normally because it is
+ permitted to branch. Fall through. */
+ }
+ else
+ {
+ int cond_negated;
+
+ /* There are conditional instructions after this one.
+ If this instruction modifies the flags, then we can
+ not predict what the next executed instruction will
+ be. Fortunately, this instruction is architecturally
+ forbidden to branch; we know it will fall through.
+ Start by skipping past it. */
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+
+ /* Set a breakpoint on the following instruction. */
+ gdb_assert ((itstate & 0x0f) != 0);
+ if (insert_bkpt)
+ insert_single_step_breakpoint (gdbarch, aspace, pc);
+ cond_negated = (itstate >> 4) & 1;
+
+ /* Skip all following instructions with the same
+ condition. If there is a later instruction in the IT
+ block with the opposite condition, set the other
+ breakpoint there. If not, then set a breakpoint on
+ the instruction after the IT block. */
+ do
+ {
+ inst1 = read_memory_unsigned_integer (pc, 2,
+ byte_order_for_code);
+ pc += thumb_insn_size (inst1);
+ itstate = thumb_advance_itstate (itstate);
+ }
+ while (itstate != 0 && ((itstate >> 4) & 1) == cond_negated);
+
+ return MAKE_THUMB_ADDR (pc);
+ }
+ }
+ }
+ else if (itstate & 0x0f)
+ {
+ /* We are in a conditional block. Check the condition. */
+ int cond = itstate >> 4;
+
+ if (! condition_true (cond, status))
+ {
+ /* Advance to the next instruction. All the 32-bit
+ instructions share a common prefix. */
+ if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
+ return MAKE_THUMB_ADDR (pc + 4);
+ else
+ return MAKE_THUMB_ADDR (pc + 2);
+ }
+
+ /* Otherwise, handle the instruction normally. */
+ }
+
+ if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
+ {
+ CORE_ADDR sp;
+
+ /* Fetch the saved PC from the stack. It's stored above
+ all of the other registers. */
+ offset = bitcount (bits (inst1, 0, 7)) * INT_REGISTER_SIZE;
+ sp = get_frame_register_unsigned (frame, ARM_SP_REGNUM);
+ nextpc = read_memory_unsigned_integer (sp + offset, 4, byte_order);
+ }
+ else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
+ {
+ unsigned long cond = bits (inst1, 8, 11);
+ if (cond == 0x0f) /* 0x0f = SWI */
+ {
+ struct gdbarch_tdep *tdep;
+ tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->syscall_next_pc != NULL)
+ nextpc = tdep->syscall_next_pc (frame);
+
+ }
+ else if (cond != 0x0f && condition_true (cond, status))
+ nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
+ }
+ else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
+ {
+ nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
+ }
+ else if ((inst1 & 0xe000) == 0xe000) /* 32-bit instruction */
+ {
+ unsigned short inst2;
+ inst2 = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code);
+
+ /* Default to the next instruction. */
+ nextpc = pc + 4;
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+
+ if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000)
+ {
+ /* Branches and miscellaneous control instructions. */
+
+ if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000)
+ {
+ /* B, BL, BLX. */
+ int j1, j2, imm1, imm2;
+
+ imm1 = sbits (inst1, 0, 10);
+ imm2 = bits (inst2, 0, 10);
+ j1 = bit (inst2, 13);
+ j2 = bit (inst2, 11);
+
+ offset = ((imm1 << 12) + (imm2 << 1));
+ offset ^= ((!j2) << 22) | ((!j1) << 23);
+
+ nextpc = pc_val + offset;
+ /* For BLX make sure to clear the low bits. */
+ if (bit (inst2, 12) == 0)
+ nextpc = nextpc & 0xfffffffc;
+ }
+ else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00)
+ {
+ /* SUBS PC, LR, #imm8. */
+ nextpc = get_frame_register_unsigned (frame, ARM_LR_REGNUM);
+ nextpc -= inst2 & 0x00ff;
+ }
+ else if ((inst2 & 0xd000) == 0x8000 && (inst1 & 0x0380) != 0x0380)
+ {
+ /* Conditional branch. */
+ if (condition_true (bits (inst1, 6, 9), status))
+ {
+ int sign, j1, j2, imm1, imm2;
+
+ sign = sbits (inst1, 10, 10);
+ imm1 = bits (inst1, 0, 5);
+ imm2 = bits (inst2, 0, 10);
+ j1 = bit (inst2, 13);
+ j2 = bit (inst2, 11);
+
+ offset = (sign << 20) + (j2 << 19) + (j1 << 18);
+ offset += (imm1 << 12) + (imm2 << 1);
+
+ nextpc = pc_val + offset;
+ }
+ }
+ }
+ else if ((inst1 & 0xfe50) == 0xe810)
+ {
+ /* Load multiple or RFE. */
+ int rn, offset, load_pc = 1;
+
+ rn = bits (inst1, 0, 3);
+ if (bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* LDMIA or POP */
+ if (!bit (inst2, 15))
+ load_pc = 0;
+ offset = bitcount (inst2) * 4 - 4;
+ }
+ else if (!bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* LDMDB */
+ if (!bit (inst2, 15))
+ load_pc = 0;
+ offset = -4;
+ }
+ else if (bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* RFEIA */
+ offset = 0;
+ }
+ else if (!bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* RFEDB */
+ offset = -8;
+ }
+ else
+ load_pc = 0;
+
+ if (load_pc)
+ {
+ CORE_ADDR addr = get_frame_register_unsigned (frame, rn);
+ nextpc = get_frame_memory_unsigned (frame, addr + offset, 4);
+ }
+ }
+ else if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00)
+ {
+ /* MOV PC or MOVS PC. */
+ nextpc = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ }
+ else if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000)
+ {
+ /* LDR PC. */
+ CORE_ADDR base;
+ int rn, load_pc = 1;
+
+ rn = bits (inst1, 0, 3);
+ base = get_frame_register_unsigned (frame, rn);
+ if (rn == ARM_PC_REGNUM)
+ {
+ base = (base + 4) & ~(CORE_ADDR) 0x3;
+ if (bit (inst1, 7))
+ base += bits (inst2, 0, 11);
+ else
+ base -= bits (inst2, 0, 11);
+ }
+ else if (bit (inst1, 7))
+ base += bits (inst2, 0, 11);
+ else if (bit (inst2, 11))
+ {
+ if (bit (inst2, 10))
+ {
+ if (bit (inst2, 9))
+ base += bits (inst2, 0, 7);
+ else
+ base -= bits (inst2, 0, 7);
+ }
+ }
+ else if ((inst2 & 0x0fc0) == 0x0000)
+ {
+ int shift = bits (inst2, 4, 5), rm = bits (inst2, 0, 3);
+ base += get_frame_register_unsigned (frame, rm) << shift;
+ }
+ else
+ /* Reserved. */
+ load_pc = 0;
+
+ if (load_pc)
+ nextpc = get_frame_memory_unsigned (frame, base, 4);
+ }
+ else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
+ {
+ /* TBB. */
+ CORE_ADDR tbl_reg, table, offset, length;
+
+ tbl_reg = bits (inst1, 0, 3);
+ if (tbl_reg == 0x0f)
+ table = pc + 4; /* Regcache copy of PC isn't right yet. */
+ else
+ table = get_frame_register_unsigned (frame, tbl_reg);
+
+ offset = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ length = 2 * get_frame_memory_unsigned (frame, table + offset, 1);
+ nextpc = pc_val + length;
+ }
+ else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf010)
+ {
+ /* TBH. */
+ CORE_ADDR tbl_reg, table, offset, length;
+
+ tbl_reg = bits (inst1, 0, 3);
+ if (tbl_reg == 0x0f)
+ table = pc + 4; /* Regcache copy of PC isn't right yet. */
+ else
+ table = get_frame_register_unsigned (frame, tbl_reg);
+
+ offset = 2 * get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ length = 2 * get_frame_memory_unsigned (frame, table + offset, 2);
+ nextpc = pc_val + length;
+ }
+ }
+ else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
+ {
+ if (bits (inst1, 3, 6) == 0x0f)
+ nextpc = pc_val;
+ else
+ nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
+ }
+ else if ((inst1 & 0xff87) == 0x4687) /* mov pc, REG */
+ {
+ if (bits (inst1, 3, 6) == 0x0f)
+ nextpc = pc_val;
+ else
+ nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
+
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ }
+ else if ((inst1 & 0xf500) == 0xb100)
+ {
+ /* CBNZ or CBZ. */
+ int imm = (bit (inst1, 9) << 6) + (bits (inst1, 3, 7) << 1);
+ ULONGEST reg = get_frame_register_unsigned (frame, bits (inst1, 0, 2));
+
+ if (bit (inst1, 11) && reg != 0)
+ nextpc = pc_val + imm;
+ else if (!bit (inst1, 11) && reg == 0)
+ nextpc = pc_val + imm;
+ }
+ return nextpc;
+}
+
+/* Get the raw next address. PC is the current program counter, in
+ FRAME. INSERT_BKPT should be TRUE if we want a breakpoint set on
+ the alternative next instruction if there are two options.
+
+ The value returned has the execution state of the next instruction
+ encoded in it. Use IS_THUMB_ADDR () to see whether the instruction is
+ in Thumb-State, and gdbarch_addr_bits_remove () to get the plain memory
+ address. */
+
+static CORE_ADDR
+arm_get_next_pc_raw (struct frame_info *frame, CORE_ADDR pc, int insert_bkpt)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned long pc_val;
+ unsigned long this_instr;
+ unsigned long status;
+ CORE_ADDR nextpc;
+
+ if (arm_frame_is_thumb (frame))
+ return thumb_get_next_pc_raw (frame, pc, insert_bkpt);
+
+ pc_val = (unsigned long) pc;
+ this_instr = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+
+ status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
+ nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
+
+ if (bits (this_instr, 28, 31) == INST_NV)
+ switch (bits (this_instr, 24, 27))
+ {
+ case 0xa:
+ case 0xb:
+ {
+ /* Branch with Link and change to Thumb. */
+ nextpc = BranchDest (pc, this_instr);
+ nextpc |= bit (this_instr, 24) << 1;
+ nextpc = MAKE_THUMB_ADDR (nextpc);
+ break;
+ }
+ case 0xc:
+ case 0xd:
+ case 0xe:
+ /* Coprocessor register transfer. */
+ if (bits (this_instr, 12, 15) == 15)
+ error (_("Invalid update to pc in instruction"));
+ break;
+ }
+ else if (condition_true (bits (this_instr, 28, 31), status))
+ {
+ switch (bits (this_instr, 24, 27))
+ {
+ case 0x0:
+ case 0x1: /* data processing */
+ case 0x2:
+ case 0x3:
+ {
+ unsigned long operand1, operand2, result = 0;
+ unsigned long rn;
+ int c;
+
+ if (bits (this_instr, 12, 15) != 15)
+ break;
+
+ if (bits (this_instr, 22, 25) == 0
+ && bits (this_instr, 4, 7) == 9) /* multiply */
+ error (_("Invalid update to pc in instruction"));
+
+ /* BX <reg>, BLX <reg> */
+ if (bits (this_instr, 4, 27) == 0x12fff1
+ || bits (this_instr, 4, 27) == 0x12fff3)
+ {
+ rn = bits (this_instr, 0, 3);
+ nextpc = ((rn == ARM_PC_REGNUM)
+ ? (pc_val + 8)
+ : get_frame_register_unsigned (frame, rn));
+
+ return nextpc;
+ }
+
+ /* Multiply into PC. */
+ c = (status & FLAG_C) ? 1 : 0;
+ rn = bits (this_instr, 16, 19);
+ operand1 = ((rn == ARM_PC_REGNUM)
+ ? (pc_val + 8)
+ : get_frame_register_unsigned (frame, rn));
+
+ if (bit (this_instr, 25))
+ {
+ unsigned long immval = bits (this_instr, 0, 7);
+ unsigned long rotate = 2 * bits (this_instr, 8, 11);
+ operand2 = ((immval >> rotate) | (immval << (32 - rotate)))
+ & 0xffffffff;
+ }
+ else /* operand 2 is a shifted register. */
+ operand2 = shifted_reg_val (frame, this_instr, c,
+ pc_val, status);
+
+ switch (bits (this_instr, 21, 24))
+ {
+ case 0x0: /*and */
+ result = operand1 & operand2;
+ break;
+
+ case 0x1: /*eor */
+ result = operand1 ^ operand2;
+ break;
+
+ case 0x2: /*sub */
+ result = operand1 - operand2;
+ break;
+
+ case 0x3: /*rsb */
+ result = operand2 - operand1;
+ break;
+
+ case 0x4: /*add */
+ result = operand1 + operand2;
+ break;
+
+ case 0x5: /*adc */
+ result = operand1 + operand2 + c;
+ break;
+
+ case 0x6: /*sbc */
+ result = operand1 - operand2 + c;
+ break;
+
+ case 0x7: /*rsc */
+ result = operand2 - operand1 + c;
+ break;
+
+ case 0x8:
+ case 0x9:
+ case 0xa:
+ case 0xb: /* tst, teq, cmp, cmn */
+ result = (unsigned long) nextpc;
+ break;
+
+ case 0xc: /*orr */
+ result = operand1 | operand2;
+ break;
+
+ case 0xd: /*mov */
+ /* Always step into a function. */
+ result = operand2;
+ break;
+
+ case 0xe: /*bic */
+ result = operand1 & ~operand2;
+ break;
+
+ case 0xf: /*mvn */
+ result = ~operand2;
+ break;
+ }
+
+ /* In 26-bit APCS the bottom two bits of the result are
+ ignored, and we always end up in ARM state. */
+ if (!arm_apcs_32)
+ nextpc = arm_addr_bits_remove (gdbarch, result);
+ else
+ nextpc = result;
+
+ break;
+ }
+
+ case 0x4:
+ case 0x5: /* data transfer */
+ case 0x6:
+ case 0x7:
+ if (bit (this_instr, 20))
+ {
+ /* load */
+ if (bits (this_instr, 12, 15) == 15)
+ {
+ /* rd == pc */
+ unsigned long rn;
+ unsigned long base;
+
+ if (bit (this_instr, 22))
+ error (_("Invalid update to pc in instruction"));
+
+ /* byte write to PC */
+ rn = bits (this_instr, 16, 19);
+ base = ((rn == ARM_PC_REGNUM)
+ ? (pc_val + 8)
+ : get_frame_register_unsigned (frame, rn));
+
+ if (bit (this_instr, 24))
+ {
+ /* pre-indexed */
+ int c = (status & FLAG_C) ? 1 : 0;
+ unsigned long offset =
+ (bit (this_instr, 25)
+ ? shifted_reg_val (frame, this_instr, c, pc_val, status)
+ : bits (this_instr, 0, 11));
+
+ if (bit (this_instr, 23))
+ base += offset;
+ else
+ base -= offset;
+ }
+ nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base,
+ 4, byte_order);
+ }
+ }
+ break;
+
+ case 0x8:
+ case 0x9: /* block transfer */
+ if (bit (this_instr, 20))
+ {
+ /* LDM */
+ if (bit (this_instr, 15))
+ {
+ /* loading pc */
+ int offset = 0;
+
+ if (bit (this_instr, 23))
+ {
+ /* up */
+ unsigned long reglist = bits (this_instr, 0, 14);
+ offset = bitcount (reglist) * 4;
+ if (bit (this_instr, 24)) /* pre */
+ offset += 4;
+ }
+ else if (bit (this_instr, 24))
+ offset = -4;
+
+ {
+ unsigned long rn_val =
+ get_frame_register_unsigned (frame,
+ bits (this_instr, 16, 19));
+ nextpc =
+ (CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val
+ + offset),
+ 4, byte_order);
+ }
+ }
+ }
+ break;
+
+ case 0xb: /* branch & link */
+ case 0xa: /* branch */
+ {
+ nextpc = BranchDest (pc, this_instr);
+ break;
+ }
+
+ case 0xc:
+ case 0xd:
+ case 0xe: /* coproc ops */
+ break;
+ case 0xf: /* SWI */
+ {
+ struct gdbarch_tdep *tdep;
+ tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->syscall_next_pc != NULL)
+ nextpc = tdep->syscall_next_pc (frame);
+
+ }
+ break;
+
+ default:
+ fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n"));
+ return (pc);
+ }
+ }
+
+ return nextpc;
+}
+
+CORE_ADDR
+arm_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ CORE_ADDR nextpc =
+ gdbarch_addr_bits_remove (gdbarch,
+ arm_get_next_pc_raw (frame, pc, TRUE));
+ if (nextpc == pc)
+ error (_("Infinite loop detected"));
+ return nextpc;
+}
+
+/* single_step() is called just before we want to resume the inferior,
+ if we want to single-step it but there is no hardware or kernel
+ single-step support. We find the target of the coming instruction
+ and breakpoint it. */
+
+int
+arm_software_single_step (struct frame_info *frame)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct address_space *aspace = get_frame_address_space (frame);
+
+ /* NOTE: This may insert the wrong breakpoint instruction when
+ single-stepping over a mode-changing instruction, if the
+ CPSR heuristics are used. */
+
+ CORE_ADDR next_pc = arm_get_next_pc (frame, get_frame_pc (frame));
+ insert_single_step_breakpoint (gdbarch, aspace, next_pc);
+
+ return 1;
+}
+
+/* Given BUF, which is OLD_LEN bytes ending at ENDADDR, expand
+ the buffer to be NEW_LEN bytes ending at ENDADDR. Return
+ NULL if an error occurs. BUF is freed. */
+
+static gdb_byte *
+extend_buffer_earlier (gdb_byte *buf, CORE_ADDR endaddr,
+ int old_len, int new_len)
+{
+ gdb_byte *new_buf, *middle;
+ int bytes_to_read = new_len - old_len;
+
+ new_buf = xmalloc (new_len);
+ memcpy (new_buf + bytes_to_read, buf, old_len);
+ xfree (buf);
+ if (target_read_memory (endaddr - new_len, new_buf, bytes_to_read) != 0)
+ {
+ xfree (new_buf);
+ return NULL;
+ }
+ return new_buf;
+}
+
+/* An IT block is at most the 2-byte IT instruction followed by
+ four 4-byte instructions. The furthest back we must search to
+ find an IT block that affects the current instruction is thus
+ 2 + 3 * 4 == 14 bytes. */
+#define MAX_IT_BLOCK_PREFIX 14
+
+/* Use a quick scan if there are more than this many bytes of
+ code. */
+#define IT_SCAN_THRESHOLD 32
+
+/* Adjust a breakpoint's address to move breakpoints out of IT blocks.
+ A breakpoint in an IT block may not be hit, depending on the
+ condition flags. */
+static CORE_ADDR
+arm_adjust_breakpoint_address (struct gdbarch *gdbarch, CORE_ADDR bpaddr)
+{
+ gdb_byte *buf;
+ char map_type;
+ CORE_ADDR boundary, func_start;
+ int buf_len, buf2_len;
+ enum bfd_endian order = gdbarch_byte_order_for_code (gdbarch);
+ int i, any, last_it, last_it_count;
+
+ /* If we are using BKPT breakpoints, none of this is necessary. */
+ if (gdbarch_tdep (gdbarch)->thumb2_breakpoint == NULL)
+ return bpaddr;
+
+ /* ARM mode does not have this problem. */
+ if (!arm_pc_is_thumb (gdbarch, bpaddr))
+ return bpaddr;
+
+ /* We are setting a breakpoint in Thumb code that could potentially
+ contain an IT block. The first step is to find how much Thumb
+ code there is; we do not need to read outside of known Thumb
+ sequences. */
+ map_type = arm_find_mapping_symbol (bpaddr, &boundary);
+ if (map_type == 0)
+ /* Thumb-2 code must have mapping symbols to have a chance. */
+ return bpaddr;
+
+ bpaddr = gdbarch_addr_bits_remove (gdbarch, bpaddr);
+
+ if (find_pc_partial_function (bpaddr, NULL, &func_start, NULL)
+ && func_start > boundary)
+ boundary = func_start;
+
+ /* Search for a candidate IT instruction. We have to do some fancy
+ footwork to distinguish a real IT instruction from the second
+ half of a 32-bit instruction, but there is no need for that if
+ there's no candidate. */
+ buf_len = min (bpaddr - boundary, MAX_IT_BLOCK_PREFIX);
+ if (buf_len == 0)
+ /* No room for an IT instruction. */
+ return bpaddr;
+
+ buf = xmalloc (buf_len);
+ if (target_read_memory (bpaddr - buf_len, buf, buf_len) != 0)
+ return bpaddr;
+ any = 0;
+ for (i = 0; i < buf_len; i += 2)
+ {
+ unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
+ if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
+ {
+ any = 1;
+ break;
+ }
+ }
+ if (any == 0)
+ {
+ xfree (buf);
+ return bpaddr;
+ }
+
+ /* OK, the code bytes before this instruction contain at least one
+ halfword which resembles an IT instruction. We know that it's
+ Thumb code, but there are still two possibilities. Either the
+ halfword really is an IT instruction, or it is the second half of
+ a 32-bit Thumb instruction. The only way we can tell is to
+ scan forwards from a known instruction boundary. */
+ if (bpaddr - boundary > IT_SCAN_THRESHOLD)
+ {
+ int definite;
+
+ /* There's a lot of code before this instruction. Start with an
+ optimistic search; it's easy to recognize halfwords that can
+ not be the start of a 32-bit instruction, and use that to
+ lock on to the instruction boundaries. */
+ buf = extend_buffer_earlier (buf, bpaddr, buf_len, IT_SCAN_THRESHOLD);
+ if (buf == NULL)
+ return bpaddr;
+ buf_len = IT_SCAN_THRESHOLD;
+
+ definite = 0;
+ for (i = 0; i < buf_len - sizeof (buf) && ! definite; i += 2)
+ {
+ unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
+ if (thumb_insn_size (inst1) == 2)
+ {
+ definite = 1;
+ break;
+ }
+ }
+
+ /* At this point, if DEFINITE, BUF[I] is the first place we
+ are sure that we know the instruction boundaries, and it is far
+ enough from BPADDR that we could not miss an IT instruction
+ affecting BPADDR. If ! DEFINITE, give up - start from a
+ known boundary. */
+ if (! definite)
+ {
+ buf = extend_buffer_earlier (buf, bpaddr, buf_len,
+ bpaddr - boundary);
+ if (buf == NULL)
+ return bpaddr;
+ buf_len = bpaddr - boundary;
+ i = 0;
+ }
+ }
+ else
+ {
+ buf = extend_buffer_earlier (buf, bpaddr, buf_len, bpaddr - boundary);
+ if (buf == NULL)
+ return bpaddr;
+ buf_len = bpaddr - boundary;
+ i = 0;
+ }
+
+ /* Scan forwards. Find the last IT instruction before BPADDR. */
+ last_it = -1;
+ last_it_count = 0;
+ while (i < buf_len)
+ {
+ unsigned short inst1 = extract_unsigned_integer (&buf[i], 2, order);
+ last_it_count--;
+ if ((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0)
+ {
+ last_it = i;
+ if (inst1 & 0x0001)
+ last_it_count = 4;
+ else if (inst1 & 0x0002)
+ last_it_count = 3;
+ else if (inst1 & 0x0004)
+ last_it_count = 2;
+ else
+ last_it_count = 1;
+ }
+ i += thumb_insn_size (inst1);
+ }
+
+ xfree (buf);
+
+ if (last_it == -1)
+ /* There wasn't really an IT instruction after all. */
+ return bpaddr;
+
+ if (last_it_count < 1)
+ /* It was too far away. */
+ return bpaddr;
+
+ /* This really is a trouble spot. Move the breakpoint to the IT
+ instruction. */
+ return bpaddr - buf_len + last_it;
+}
+
+/* ARM displaced stepping support.
+
+ Generally ARM displaced stepping works as follows:
+
+ 1. When an instruction is to be single-stepped, it is first decoded by
+ arm_process_displaced_insn (called from arm_displaced_step_copy_insn).
+ Depending on the type of instruction, it is then copied to a scratch
+ location, possibly in a modified form. The copy_* set of functions
+ performs such modification, as necessary. A breakpoint is placed after
+ the modified instruction in the scratch space to return control to GDB.
+ Note in particular that instructions which modify the PC will no longer
+ do so after modification.
+
+ 2. The instruction is single-stepped, by setting the PC to the scratch
+ location address, and resuming. Control returns to GDB when the
+ breakpoint is hit.
+
+ 3. A cleanup function (cleanup_*) is called corresponding to the copy_*
+ function used for the current instruction. This function's job is to
+ put the CPU/memory state back to what it would have been if the
+ instruction had been executed unmodified in its original location. */
+
+/* NOP instruction (mov r0, r0). */
+#define ARM_NOP 0xe1a00000
+
+/* Helper for register reads for displaced stepping. In particular, this
+ returns the PC as it would be seen by the instruction at its original
+ location. */
+
+ULONGEST
+displaced_read_reg (struct regcache *regs, struct displaced_step_closure *dsc,
+ int regno)
+{
+ ULONGEST ret;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (regno == ARM_PC_REGNUM)
+ {
+ /* Compute pipeline offset:
+ - When executing an ARM instruction, PC reads as the address of the
+ current instruction plus 8.
+ - When executing a Thumb instruction, PC reads as the address of the
+ current instruction plus 4. */
+
+ if (!dsc->is_thumb)
+ from += 8;
+ else
+ from += 4;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: read pc value %.8lx\n",
+ (unsigned long) from);
+ return (ULONGEST) from;
+ }
+ else
+ {
+ regcache_cooked_read_unsigned (regs, regno, &ret);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: read r%d value %.8lx\n",
+ regno, (unsigned long) ret);
+ return ret;
+ }
+}
+
+static int
+displaced_in_arm_mode (struct regcache *regs)
+{
+ ULONGEST ps;
+ ULONGEST t_bit = arm_psr_thumb_bit (get_regcache_arch (regs));
+
+ regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+
+ return (ps & t_bit) == 0;
+}
+
+/* Write to the PC as from a branch instruction. */
+
+static void
+branch_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+ ULONGEST val)
+{
+ if (!dsc->is_thumb)
+ /* Note: If bits 0/1 are set, this branch would be unpredictable for
+ architecture versions < 6. */
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM,
+ val & ~(ULONGEST) 0x3);
+ else
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM,
+ val & ~(ULONGEST) 0x1);
+}
+
+/* Write to the PC as from a branch-exchange instruction. */
+
+static void
+bx_write_pc (struct regcache *regs, ULONGEST val)
+{
+ ULONGEST ps;
+ ULONGEST t_bit = arm_psr_thumb_bit (get_regcache_arch (regs));
+
+ regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+
+ if ((val & 1) == 1)
+ {
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps | t_bit);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffe);
+ }
+ else if ((val & 2) == 0)
+ {
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps & ~t_bit);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val);
+ }
+ else
+ {
+ /* Unpredictable behaviour. Try to do something sensible (switch to ARM
+ mode, align dest to 4 bytes). */
+ warning (_("Single-stepping BX to non-word-aligned ARM instruction."));
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps & ~t_bit);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffc);
+ }
+}
+
+/* Write to the PC as if from a load instruction. */
+
+static void
+load_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+ ULONGEST val)
+{
+ if (DISPLACED_STEPPING_ARCH_VERSION >= 5)
+ bx_write_pc (regs, val);
+ else
+ branch_write_pc (regs, dsc, val);
+}
+
+/* Write to the PC as if from an ALU instruction. */
+
+static void
+alu_write_pc (struct regcache *regs, struct displaced_step_closure *dsc,
+ ULONGEST val)
+{
+ if (DISPLACED_STEPPING_ARCH_VERSION >= 7 && !dsc->is_thumb)
+ bx_write_pc (regs, val);
+ else
+ branch_write_pc (regs, dsc, val);
+}
+
+/* Helper for writing to registers for displaced stepping. Writing to the PC
+ has a varying effects depending on the instruction which does the write:
+ this is controlled by the WRITE_PC argument. */
+
+void
+displaced_write_reg (struct regcache *regs, struct displaced_step_closure *dsc,
+ int regno, ULONGEST val, enum pc_write_style write_pc)
+{
+ if (regno == ARM_PC_REGNUM)
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing pc %.8lx\n",
+ (unsigned long) val);
+ switch (write_pc)
+ {
+ case BRANCH_WRITE_PC:
+ branch_write_pc (regs, dsc, val);
+ break;
+
+ case BX_WRITE_PC:
+ bx_write_pc (regs, val);
+ break;
+
+ case LOAD_WRITE_PC:
+ load_write_pc (regs, dsc, val);
+ break;
+
+ case ALU_WRITE_PC:
+ alu_write_pc (regs, dsc, val);
+ break;
+
+ case CANNOT_WRITE_PC:
+ warning (_("Instruction wrote to PC in an unexpected way when "
+ "single-stepping"));
+ break;
+
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("Invalid argument to displaced_write_reg"));
+ }
+
+ dsc->wrote_to_pc = 1;
+ }
+ else
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing r%d value %.8lx\n",
+ regno, (unsigned long) val);
+ regcache_cooked_write_unsigned (regs, regno, val);
+ }
+}
+
+/* This function is used to concisely determine if an instruction INSN
+ references PC. Register fields of interest in INSN should have the
+ corresponding fields of BITMASK set to 0b1111. The function
+ returns return 1 if any of these fields in INSN reference the PC
+ (also 0b1111, r15), else it returns 0. */
+
+static int
+insn_references_pc (uint32_t insn, uint32_t bitmask)
+{
+ uint32_t lowbit = 1;
+
+ while (bitmask != 0)
+ {
+ uint32_t mask;
+
+ for (; lowbit && (bitmask & lowbit) == 0; lowbit <<= 1)
+ ;
+
+ if (!lowbit)
+ break;
+
+ mask = lowbit * 0xf;
+
+ if ((insn & mask) == mask)
+ return 1;
+
+ bitmask &= ~mask;
+ }
+
+ return 0;
+}
+
+/* The simplest copy function. Many instructions have the same effect no
+ matter what address they are executed at: in those cases, use this. */
+
+static int
+copy_unmodified (struct gdbarch *gdbarch, uint32_t insn,
+ const char *iname, struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.8lx, "
+ "opcode/class '%s' unmodified\n", (unsigned long) insn,
+ iname);
+
+ dsc->modinsn[0] = insn;
+
+ return 0;
+}
+
+/* Preload instructions with immediate offset. */
+
+static void
+cleanup_preload (struct gdbarch *gdbarch,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (!dsc->u.preload.immed)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+}
+
+static int
+copy_preload (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ ULONGEST rn_val;
+
+ if (!insn_references_pc (insn, 0x000f0000ul))
+ return copy_unmodified (gdbarch, insn, "preload", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
+ (unsigned long) insn);
+
+ /* Preload instructions:
+
+ {pli/pld} [rn, #+/-imm]
+ ->
+ {pli/pld} [r0, #+/-imm]. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+
+ dsc->u.preload.immed = 1;
+
+ dsc->modinsn[0] = insn & 0xfff0ffff;
+
+ dsc->cleanup = &cleanup_preload;
+
+ return 0;
+}
+
+/* Preload instructions with register offset. */
+
+static int
+copy_preload_reg (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ ULONGEST rn_val, rm_val;
+
+ if (!insn_references_pc (insn, 0x000f000ful))
+ return copy_unmodified (gdbarch, insn, "preload reg", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
+ (unsigned long) insn);
+
+ /* Preload register-offset instructions:
+
+ {pli/pld} [rn, rm {, shift}]
+ ->
+ {pli/pld} [r0, r1 {, shift}]. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rm_val = displaced_read_reg (regs, dsc, rm);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rm_val, CANNOT_WRITE_PC);
+
+ dsc->u.preload.immed = 0;
+
+ dsc->modinsn[0] = (insn & 0xfff0fff0) | 0x1;
+
+ dsc->cleanup = &cleanup_preload;
+
+ return 0;
+}
+
+/* Copy/cleanup coprocessor load and store instructions. */
+
+static void
+cleanup_copro_load_store (struct gdbarch *gdbarch,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST rn_val = displaced_read_reg (regs, dsc, 0);
+
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, LOAD_WRITE_PC);
+}
+
+static int
+copy_copro_load_store (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ ULONGEST rn_val;
+
+ if (!insn_references_pc (insn, 0x000f0000ul))
+ return copy_unmodified (gdbarch, insn, "copro load/store", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying coprocessor "
+ "load/store insn %.8lx\n", (unsigned long) insn);
+
+ /* Coprocessor load/store instructions:
+
+ {stc/stc2} [<Rn>, #+/-imm] (and other immediate addressing modes)
+ ->
+ {stc/stc2} [r0, #+/-imm].
+
+ ldc/ldc2 are handled identically. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+
+ dsc->u.ldst.writeback = bit (insn, 25);
+ dsc->u.ldst.rn = rn;
+
+ dsc->modinsn[0] = insn & 0xfff0ffff;
+
+ dsc->cleanup = &cleanup_copro_load_store;
+
+ return 0;
+}
+
+/* Clean up branch instructions (actually perform the branch, by setting
+ PC). */
+
+static void
+cleanup_branch (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int branch_taken = condition_true (dsc->u.branch.cond, status);
+ enum pc_write_style write_pc = dsc->u.branch.exchange
+ ? BX_WRITE_PC : BRANCH_WRITE_PC;
+
+ if (!branch_taken)
+ return;
+
+ if (dsc->u.branch.link)
+ {
+ ULONGEST pc = displaced_read_reg (regs, dsc, ARM_PC_REGNUM);
+ displaced_write_reg (regs, dsc, ARM_LR_REGNUM, pc - 4, CANNOT_WRITE_PC);
+ }
+
+ displaced_write_reg (regs, dsc, ARM_PC_REGNUM, dsc->u.branch.dest, write_pc);
+}
+
+/* Copy B/BL/BLX instructions with immediate destinations. */
+
+static int
+copy_b_bl_blx (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int cond = bits (insn, 28, 31);
+ int exchange = (cond == 0xf);
+ int link = exchange || bit (insn, 24);
+ CORE_ADDR from = dsc->insn_addr;
+ long offset;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s immediate insn "
+ "%.8lx\n", (exchange) ? "blx" : (link) ? "bl" : "b",
+ (unsigned long) insn);
+
+ /* Implement "BL<cond> <label>" as:
+
+ Preparation: cond <- instruction condition
+ Insn: mov r0, r0 (nop)
+ Cleanup: if (condition true) { r14 <- pc; pc <- label }.
+
+ B<cond> similar, but don't set r14 in cleanup. */
+
+ if (exchange)
+ /* For BLX, set bit 0 of the destination. The cleanup_branch function will
+ then arrange the switch into Thumb mode. */
+ offset = (bits (insn, 0, 23) << 2) | (bit (insn, 24) << 1) | 1;
+ else
+ offset = bits (insn, 0, 23) << 2;
+
+ if (bit (offset, 25))
+ offset = offset | ~0x3ffffff;
+
+ dsc->u.branch.cond = cond;
+ dsc->u.branch.link = link;
+ dsc->u.branch.exchange = exchange;
+ dsc->u.branch.dest = from + 8 + offset;
+
+ dsc->modinsn[0] = ARM_NOP;
+
+ dsc->cleanup = &cleanup_branch;
+
+ return 0;
+}
+
+/* Copy BX/BLX with register-specified destinations. */
+
+static int
+copy_bx_blx_reg (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int cond = bits (insn, 28, 31);
+ /* BX: x12xxx1x
+ BLX: x12xxx3x. */
+ int link = bit (insn, 5);
+ unsigned int rm = bits (insn, 0, 3);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s register insn "
+ "%.8lx\n", (link) ? "blx" : "bx",
+ (unsigned long) insn);
+
+ /* Implement {BX,BLX}<cond> <reg>" as:
+
+ Preparation: cond <- instruction condition
+ Insn: mov r0, r0 (nop)
+ Cleanup: if (condition true) { r14 <- pc; pc <- dest; }.
+
+ Don't set r14 in cleanup for BX. */
+
+ dsc->u.branch.dest = displaced_read_reg (regs, dsc, rm);
+
+ dsc->u.branch.cond = cond;
+ dsc->u.branch.link = link;
+ dsc->u.branch.exchange = 1;
+
+ dsc->modinsn[0] = ARM_NOP;
+
+ dsc->cleanup = &cleanup_branch;
+
+ return 0;
+}
+
+/* Copy/cleanup arithmetic/logic instruction with immediate RHS. */
+
+static void
+cleanup_alu_imm (struct gdbarch *gdbarch,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val = displaced_read_reg (regs, dsc, 0);
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
+
+static int
+copy_alu_imm (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rd = bits (insn, 12, 15);
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd);
+ ULONGEST rd_val, rn_val;
+
+ if (!insn_references_pc (insn, 0x000ff000ul))
+ return copy_unmodified (gdbarch, insn, "ALU immediate", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying immediate %s insn "
+ "%.8lx\n", is_mov ? "move" : "ALU",
+ (unsigned long) insn);
+
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] #imm
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2 <- r0, r1;
+ r0, r1 <- rd, rn
+ Insn: <op><cond> r0, r1, #imm
+ Cleanup: rd <- r0; r0 <- tmp1; r1 <- tmp2
+ */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rd_val = displaced_read_reg (regs, dsc, rd);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+
+ if (is_mov)
+ dsc->modinsn[0] = insn & 0xfff00fff;
+ else
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x10000;
+
+ dsc->cleanup = &cleanup_alu_imm;
+
+ return 0;
+}
+
+/* Copy/cleanup arithmetic/logic insns with register RHS. */
+
+static void
+cleanup_alu_reg (struct gdbarch *gdbarch,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val;
+ int i;
+
+ rd_val = displaced_read_reg (regs, dsc, 0);
+
+ for (i = 0; i < 3; i++)
+ displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
+
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
+
+static int
+copy_alu_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ unsigned int rd = bits (insn, 12, 15);
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd);
+ ULONGEST rd_val, rn_val, rm_val;
+
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return copy_unmodified (gdbarch, insn, "ALU reg", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying reg %s insn %.8lx\n",
+ is_mov ? "move" : "ALU", (unsigned long) insn);
+
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] rm [, <shift>]
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2, tmp3 <- r0, r1, r2;
+ r0, r1, r2 <- rd, rn, rm
+ Insn: <op><cond> r0, r1, r2 [, <shift>]
+ Cleanup: rd <- r0; r0, r1, r2 <- tmp1, tmp2, tmp3
+ */
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ rd_val = displaced_read_reg (regs, dsc, rd);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rm_val = displaced_read_reg (regs, dsc, rm);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+
+ if (is_mov)
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x2;
+ else
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x10002;
+
+ dsc->cleanup = &cleanup_alu_reg;
+
+ return 0;
+}
+
+/* Cleanup/copy arithmetic/logic insns with shifted register RHS. */
+
+static void
+cleanup_alu_shifted_reg (struct gdbarch *gdbarch,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val = displaced_read_reg (regs, dsc, 0);
+ int i;
+
+ for (i = 0; i < 4; i++)
+ displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
+
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
+
+static int
+copy_alu_shifted_reg (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ unsigned int rd = bits (insn, 12, 15);
+ unsigned int rs = bits (insn, 8, 11);
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd), i;
+ ULONGEST rd_val, rn_val, rm_val, rs_val;
+
+ if (!insn_references_pc (insn, 0x000fff0ful))
+ return copy_unmodified (gdbarch, insn, "ALU shifted reg", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying shifted reg %s insn "
+ "%.8lx\n", is_mov ? "move" : "ALU",
+ (unsigned long) insn);
+
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] rm, <shift> rs
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2, tmp3, tmp4 <- r0, r1, r2, r3
+ r0, r1, r2, r3 <- rd, rn, rm, rs
+ Insn: <op><cond> r0, r1, r2, <shift> r3
+ Cleanup: tmp5 <- r0
+ r0, r1, r2, r3 <- tmp1, tmp2, tmp3, tmp4
+ rd <- tmp5
+ */
+
+ for (i = 0; i < 4; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, dsc, i);
+
+ rd_val = displaced_read_reg (regs, dsc, rd);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ rm_val = displaced_read_reg (regs, dsc, rm);
+ rs_val = displaced_read_reg (regs, dsc, rs);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 3, rs_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+
+ if (is_mov)
+ dsc->modinsn[0] = (insn & 0xfff000f0) | 0x302;
+ else
+ dsc->modinsn[0] = (insn & 0xfff000f0) | 0x10302;
-/* Always align the frame to an 8-byte boundary. This is required on
- some platforms and harmless on the rest. */
+ dsc->cleanup = &cleanup_alu_shifted_reg;
-static CORE_ADDR
-arm_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
-{
- /* Align the stack to eight bytes. */
- return sp & ~ (CORE_ADDR) 7;
+ return 0;
}
+/* Clean up load instructions. */
+
static void
-print_fpu_flags (int flags)
+cleanup_load (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- if (flags & (1 << 0))
- fputs ("IVO ", stdout);
- if (flags & (1 << 1))
- fputs ("DVZ ", stdout);
- if (flags & (1 << 2))
- fputs ("OFL ", stdout);
- if (flags & (1 << 3))
- fputs ("UFL ", stdout);
- if (flags & (1 << 4))
- fputs ("INX ", stdout);
- putchar ('\n');
+ ULONGEST rt_val, rt_val2 = 0, rn_val;
+
+ rt_val = displaced_read_reg (regs, dsc, 0);
+ if (dsc->u.ldst.xfersize == 8)
+ rt_val2 = displaced_read_reg (regs, dsc, 1);
+ rn_val = displaced_read_reg (regs, dsc, 2);
+
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (dsc->u.ldst.xfersize > 4)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.immed)
+ displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
+
+ /* Handle register writeback. */
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
+ /* Put result in right place. */
+ displaced_write_reg (regs, dsc, dsc->rd, rt_val, LOAD_WRITE_PC);
+ if (dsc->u.ldst.xfersize == 8)
+ displaced_write_reg (regs, dsc, dsc->rd + 1, rt_val2, LOAD_WRITE_PC);
}
-/* Print interesting information about the floating point processor
- (if present) or emulator. */
+/* Clean up store instructions. */
+
static void
-arm_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
- struct frame_info *frame, const char *args)
+cleanup_store (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- unsigned long status = get_frame_register_unsigned (frame, ARM_FPS_REGNUM);
- int type;
-
- type = (status >> 24) & 127;
- if (status & (1 << 31))
- printf (_("Hardware FPU type %d\n"), type);
- else
- printf (_("Software FPU type %d\n"), type);
- /* i18n: [floating point unit] mask */
- fputs (_("mask: "), stdout);
- print_fpu_flags (status >> 16);
- /* i18n: [floating point unit] flags */
- fputs (_("flags: "), stdout);
- print_fpu_flags (status);
+ ULONGEST rn_val = displaced_read_reg (regs, dsc, 2);
+
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (dsc->u.ldst.xfersize > 4)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.immed)
+ displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.restore_r4)
+ displaced_write_reg (regs, dsc, 4, dsc->tmp[4], CANNOT_WRITE_PC);
+
+ /* Writeback. */
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
}
-/* Return the GDB type object for the "standard" data type of data in
- register N. */
+/* Copy "extra" load/store instructions. These are halfword/doubleword
+ transfers, which have a different encoding to byte/word transfers. */
-static struct type *
-arm_register_type (struct gdbarch *gdbarch, int regnum)
+static int
+copy_extra_ld_st (struct gdbarch *gdbarch, uint32_t insn, int unpriveleged,
+ struct regcache *regs, struct displaced_step_closure *dsc)
{
- if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS)
- return builtin_type_arm_ext;
- else if (regnum == ARM_SP_REGNUM)
- return builtin_type_void_data_ptr;
- else if (regnum == ARM_PC_REGNUM)
- return builtin_type_void_func_ptr;
- else if (regnum >= ARRAY_SIZE (arm_register_names))
- /* These registers are only supported on targets which supply
- an XML description. */
- return builtin_type_int0;
+ unsigned int op1 = bits (insn, 20, 24);
+ unsigned int op2 = bits (insn, 5, 6);
+ unsigned int rt = bits (insn, 12, 15);
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ char load[12] = {0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1};
+ char bytesize[12] = {2, 2, 2, 2, 8, 1, 8, 1, 8, 2, 8, 2};
+ int immed = (op1 & 0x4) != 0;
+ int opcode;
+ ULONGEST rt_val, rt_val2 = 0, rn_val, rm_val = 0;
+
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return copy_unmodified (gdbarch, insn, "extra load/store", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %sextra load/store "
+ "insn %.8lx\n", unpriveleged ? "unpriveleged " : "",
+ (unsigned long) insn);
+
+ opcode = ((op2 << 2) | (op1 & 0x1) | ((op1 & 0x4) >> 1)) - 4;
+
+ if (opcode < 0)
+ internal_error (__FILE__, __LINE__,
+ _("copy_extra_ld_st: instruction decode error"));
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, dsc, 1);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ if (!immed)
+ dsc->tmp[3] = displaced_read_reg (regs, dsc, 3);
+
+ rt_val = displaced_read_reg (regs, dsc, rt);
+ if (bytesize[opcode] == 8)
+ rt_val2 = displaced_read_reg (regs, dsc, rt + 1);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ if (!immed)
+ rm_val = displaced_read_reg (regs, dsc, rm);
+
+ displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
+ if (bytesize[opcode] == 8)
+ displaced_write_reg (regs, dsc, 1, rt_val2, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
+ if (!immed)
+ displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+
+ dsc->rd = rt;
+ dsc->u.ldst.xfersize = bytesize[opcode];
+ dsc->u.ldst.rn = rn;
+ dsc->u.ldst.immed = immed;
+ dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0;
+ dsc->u.ldst.restore_r4 = 0;
+
+ if (immed)
+ /* {ldr,str}<width><cond> rt, [rt2,] [rn, #imm]
+ ->
+ {ldr,str}<width><cond> r0, [r1,] [r2, #imm]. */
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
else
- return builtin_type_uint32;
+ /* {ldr,str}<width><cond> rt, [rt2,] [rn, +/-rm]
+ ->
+ {ldr,str}<width><cond> r0, [r1,] [r2, +/-r3]. */
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
+
+ dsc->cleanup = load[opcode] ? &cleanup_load : &cleanup_store;
+
+ return 0;
}
-/* Map a DWARF register REGNUM onto the appropriate GDB register
- number. */
+/* Copy byte/word loads and stores. */
static int
-arm_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int reg)
+copy_ldr_str_ldrb_strb (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc, int load, int byte,
+ int usermode)
{
- /* Core integer regs. */
- if (reg >= 0 && reg <= 15)
- return reg;
-
- /* Legacy FPA encoding. These were once used in a way which
- overlapped with VFP register numbering, so their use is
- discouraged, but GDB doesn't support the ARM toolchain
- which used them for VFP. */
- if (reg >= 16 && reg <= 23)
- return ARM_F0_REGNUM + reg - 16;
+ int immed = !bit (insn, 25);
+ unsigned int rt = bits (insn, 12, 15);
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3); /* Only valid if !immed. */
+ ULONGEST rt_val, rn_val, rm_val = 0;
+
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return copy_unmodified (gdbarch, insn, "load/store", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s%s insn %.8lx\n",
+ load ? (byte ? "ldrb" : "ldr")
+ : (byte ? "strb" : "str"), usermode ? "t" : "",
+ (unsigned long) insn);
+
+ dsc->tmp[0] = displaced_read_reg (regs, dsc, 0);
+ dsc->tmp[2] = displaced_read_reg (regs, dsc, 2);
+ if (!immed)
+ dsc->tmp[3] = displaced_read_reg (regs, dsc, 3);
+ if (!load)
+ dsc->tmp[4] = displaced_read_reg (regs, dsc, 4);
+
+ rt_val = displaced_read_reg (regs, dsc, rt);
+ rn_val = displaced_read_reg (regs, dsc, rn);
+ if (!immed)
+ rm_val = displaced_read_reg (regs, dsc, rm);
+
+ displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
+ if (!immed)
+ displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+
+ dsc->rd = rt;
+ dsc->u.ldst.xfersize = byte ? 1 : 4;
+ dsc->u.ldst.rn = rn;
+ dsc->u.ldst.immed = immed;
+ dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0;
+
+ /* To write PC we can do:
+
+ Before this sequence of instructions:
+ r0 is the PC value got from displaced_read_reg, so r0 = from + 8;
+ r2 is the Rn value got from dispalced_read_reg.
+
+ Insn1: push {pc} Write address of STR instruction + offset on stack
+ Insn2: pop {r4} Read it back from stack, r4 = addr(Insn1) + offset
+ Insn3: sub r4, r4, pc r4 = addr(Insn1) + offset - pc
+ = addr(Insn1) + offset - addr(Insn3) - 8
+ = offset - 16
+ Insn4: add r4, r4, #8 r4 = offset - 8
+ Insn5: add r0, r0, r4 r0 = from + 8 + offset - 8
+ = from + offset
+ Insn6: str r0, [r2, #imm] (or str r0, [r2, r3])
+
+ Otherwise we don't know what value to write for PC, since the offset is
+ architecture-dependent (sometimes PC+8, sometimes PC+12). More details
+ of this can be found in Section "Saving from r15" in
+ http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0204g/Cihbjifh.html */
+
+ if (load || rt != ARM_PC_REGNUM)
+ {
+ dsc->u.ldst.restore_r4 = 0;
- /* New assignments for the FPA registers. */
- if (reg >= 96 && reg <= 103)
- return ARM_F0_REGNUM + reg - 96;
+ if (immed)
+ /* {ldr,str}[b]<cond> rt, [rn, #imm], etc.
+ ->
+ {ldr,str}[b]<cond> r0, [r2, #imm]. */
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
+ else
+ /* {ldr,str}[b]<cond> rt, [rn, rm], etc.
+ ->
+ {ldr,str}[b]<cond> r0, [r2, r3]. */
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
+ }
+ else
+ {
+ /* We need to use r4 as scratch. Make sure it's restored afterwards. */
+ dsc->u.ldst.restore_r4 = 1;
+ dsc->modinsn[0] = 0xe92d8000; /* push {pc} */
+ dsc->modinsn[1] = 0xe8bd0010; /* pop {r4} */
+ dsc->modinsn[2] = 0xe044400f; /* sub r4, r4, pc. */
+ dsc->modinsn[3] = 0xe2844008; /* add r4, r4, #8. */
+ dsc->modinsn[4] = 0xe0800004; /* add r0, r0, r4. */
+
+ /* As above. */
+ if (immed)
+ dsc->modinsn[5] = (insn & 0xfff00fff) | 0x20000;
+ else
+ dsc->modinsn[5] = (insn & 0xfff00ff0) | 0x20003;
- /* WMMX register assignments. */
- if (reg >= 104 && reg <= 111)
- return ARM_WCGR0_REGNUM + reg - 104;
+ dsc->modinsn[6] = 0x0; /* breakpoint location. */
+ dsc->modinsn[7] = 0x0; /* scratch space. */
- if (reg >= 112 && reg <= 127)
- return ARM_WR0_REGNUM + reg - 112;
+ dsc->numinsns = 6;
+ }
- if (reg >= 192 && reg <= 199)
- return ARM_WC0_REGNUM + reg - 192;
+ dsc->cleanup = load ? &cleanup_load : &cleanup_store;
- return -1;
+ return 0;
}
-/* Map GDB internal REGNUM onto the Arm simulator register numbers. */
-static int
-arm_register_sim_regno (struct gdbarch *gdbarch, int regnum)
+/* Cleanup LDM instructions with fully-populated register list. This is an
+ unfortunate corner case: it's impossible to implement correctly by modifying
+ the instruction. The issue is as follows: we have an instruction,
+
+ ldm rN, {r0-r15}
+
+ which we must rewrite to avoid loading PC. A possible solution would be to
+ do the load in two halves, something like (with suitable cleanup
+ afterwards):
+
+ mov r8, rN
+ ldm[id][ab] r8!, {r0-r7}
+ str r7, <temp>
+ ldm[id][ab] r8, {r7-r14}
+ <bkpt>
+
+ but at present there's no suitable place for <temp>, since the scratch space
+ is overwritten before the cleanup routine is called. For now, we simply
+ emulate the instruction. */
+
+static void
+cleanup_block_load_all (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- int reg = regnum;
- gdb_assert (reg >= 0 && reg < gdbarch_num_regs (gdbarch));
+ int inc = dsc->u.block.increment;
+ int bump_before = dsc->u.block.before ? (inc ? 4 : -4) : 0;
+ int bump_after = dsc->u.block.before ? 0 : (inc ? 4 : -4);
+ uint32_t regmask = dsc->u.block.regmask;
+ int regno = inc ? 0 : 15;
+ CORE_ADDR xfer_addr = dsc->u.block.xfer_addr;
+ int exception_return = dsc->u.block.load && dsc->u.block.user
+ && (regmask & 0x8000) != 0;
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int do_transfer = condition_true (dsc->u.block.cond, status);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+
+ if (!do_transfer)
+ return;
- if (regnum >= ARM_WR0_REGNUM && regnum <= ARM_WR15_REGNUM)
- return regnum - ARM_WR0_REGNUM + SIM_ARM_IWMMXT_COP0R0_REGNUM;
+ /* If the instruction is ldm rN, {...pc}^, I don't think there's anything
+ sensible we can do here. Complain loudly. */
+ if (exception_return)
+ error (_("Cannot single-step exception return"));
- if (regnum >= ARM_WC0_REGNUM && regnum <= ARM_WC7_REGNUM)
- return regnum - ARM_WC0_REGNUM + SIM_ARM_IWMMXT_COP1R0_REGNUM;
+ /* We don't handle any stores here for now. */
+ gdb_assert (dsc->u.block.load != 0);
- if (regnum >= ARM_WCGR0_REGNUM && regnum <= ARM_WCGR7_REGNUM)
- return regnum - ARM_WCGR0_REGNUM + SIM_ARM_IWMMXT_COP1R8_REGNUM;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: emulating block transfer: "
+ "%s %s %s\n", dsc->u.block.load ? "ldm" : "stm",
+ dsc->u.block.increment ? "inc" : "dec",
+ dsc->u.block.before ? "before" : "after");
- if (reg < NUM_GREGS)
- return SIM_ARM_R0_REGNUM + reg;
- reg -= NUM_GREGS;
+ while (regmask)
+ {
+ uint32_t memword;
- if (reg < NUM_FREGS)
- return SIM_ARM_FP0_REGNUM + reg;
- reg -= NUM_FREGS;
+ if (inc)
+ while (regno <= ARM_PC_REGNUM && (regmask & (1 << regno)) == 0)
+ regno++;
+ else
+ while (regno >= 0 && (regmask & (1 << regno)) == 0)
+ regno--;
- if (reg < NUM_SREGS)
- return SIM_ARM_FPS_REGNUM + reg;
- reg -= NUM_SREGS;
+ xfer_addr += bump_before;
- internal_error (__FILE__, __LINE__, _("Bad REGNUM %d"), regnum);
+ memword = read_memory_unsigned_integer (xfer_addr, 4, byte_order);
+ displaced_write_reg (regs, dsc, regno, memword, LOAD_WRITE_PC);
+
+ xfer_addr += bump_after;
+
+ regmask &= ~(1 << regno);
+ }
+
+ if (dsc->u.block.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.block.rn, xfer_addr,
+ CANNOT_WRITE_PC);
}
-/* NOTE: cagney/2001-08-20: Both convert_from_extended() and
- convert_to_extended() use floatformat_arm_ext_littlebyte_bigword.
- It is thought that this is is the floating-point register format on
- little-endian systems. */
+/* Clean up an STM which included the PC in the register list. */
static void
-convert_from_extended (const struct floatformat *fmt, const void *ptr,
- void *dbl, int endianess)
+cleanup_block_store_pc (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- DOUBLEST d;
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int store_executed = condition_true (dsc->u.block.cond, status);
+ CORE_ADDR pc_stored_at, transferred_regs = bitcount (dsc->u.block.regmask);
+ CORE_ADDR stm_insn_addr;
+ uint32_t pc_val;
+ long offset;
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+
+ /* If condition code fails, there's nothing else to do. */
+ if (!store_executed)
+ return;
- if (endianess == BFD_ENDIAN_BIG)
- floatformat_to_doublest (&floatformat_arm_ext_big, ptr, &d);
+ if (dsc->u.block.increment)
+ {
+ pc_stored_at = dsc->u.block.xfer_addr + 4 * transferred_regs;
+
+ if (dsc->u.block.before)
+ pc_stored_at += 4;
+ }
else
- floatformat_to_doublest (&floatformat_arm_ext_littlebyte_bigword,
- ptr, &d);
- floatformat_from_doublest (fmt, &d, dbl);
+ {
+ pc_stored_at = dsc->u.block.xfer_addr;
+
+ if (dsc->u.block.before)
+ pc_stored_at -= 4;
+ }
+
+ pc_val = read_memory_unsigned_integer (pc_stored_at, 4, byte_order);
+ stm_insn_addr = dsc->scratch_base;
+ offset = pc_val - stm_insn_addr;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: detected PC offset %.8lx for "
+ "STM instruction\n", offset);
+
+ /* Rewrite the stored PC to the proper value for the non-displaced original
+ instruction. */
+ write_memory_unsigned_integer (pc_stored_at, 4, byte_order,
+ dsc->insn_addr + offset);
}
+/* Clean up an LDM which includes the PC in the register list. We clumped all
+ the registers in the transferred list into a contiguous range r0...rX (to
+ avoid loading PC directly and losing control of the debugged program), so we
+ must undo that here. */
+
static void
-convert_to_extended (const struct floatformat *fmt, void *dbl, const void *ptr,
- int endianess)
+cleanup_block_load_pc (struct gdbarch *gdbarch,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- DOUBLEST d;
+ uint32_t status = displaced_read_reg (regs, dsc, ARM_PS_REGNUM);
+ int load_executed = condition_true (dsc->u.block.cond, status), i;
+ unsigned int mask = dsc->u.block.regmask, write_reg = ARM_PC_REGNUM;
+ unsigned int regs_loaded = bitcount (mask);
+ unsigned int num_to_shuffle = regs_loaded, clobbered;
- floatformat_to_doublest (fmt, ptr, &d);
- if (endianess == BFD_ENDIAN_BIG)
- floatformat_from_doublest (&floatformat_arm_ext_big, &d, dbl);
- else
- floatformat_from_doublest (&floatformat_arm_ext_littlebyte_bigword,
- &d, dbl);
+ /* The method employed here will fail if the register list is fully populated
+ (we need to avoid loading PC directly). */
+ gdb_assert (num_to_shuffle < 16);
+
+ if (!load_executed)
+ return;
+
+ clobbered = (1 << num_to_shuffle) - 1;
+
+ while (num_to_shuffle > 0)
+ {
+ if ((mask & (1 << write_reg)) != 0)
+ {
+ unsigned int read_reg = num_to_shuffle - 1;
+
+ if (read_reg != write_reg)
+ {
+ ULONGEST rval = displaced_read_reg (regs, dsc, read_reg);
+ displaced_write_reg (regs, dsc, write_reg, rval, LOAD_WRITE_PC);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: move "
+ "loaded register r%d to r%d\n"), read_reg,
+ write_reg);
+ }
+ else if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: register "
+ "r%d already in the right place\n"),
+ write_reg);
+
+ clobbered &= ~(1 << write_reg);
+
+ num_to_shuffle--;
+ }
+
+ write_reg--;
+ }
+
+ /* Restore any registers we scribbled over. */
+ for (write_reg = 0; clobbered != 0; write_reg++)
+ {
+ if ((clobbered & (1 << write_reg)) != 0)
+ {
+ displaced_write_reg (regs, dsc, write_reg, dsc->tmp[write_reg],
+ CANNOT_WRITE_PC);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: restored "
+ "clobbered register r%d\n"), write_reg);
+ clobbered &= ~(1 << write_reg);
+ }
+ }
+
+ /* Perform register writeback manually. */
+ if (dsc->u.block.writeback)
+ {
+ ULONGEST new_rn_val = dsc->u.block.xfer_addr;
+
+ if (dsc->u.block.increment)
+ new_rn_val += regs_loaded * 4;
+ else
+ new_rn_val -= regs_loaded * 4;
+
+ displaced_write_reg (regs, dsc, dsc->u.block.rn, new_rn_val,
+ CANNOT_WRITE_PC);
+ }
}
+/* Handle ldm/stm, apart from some tricky cases which are unlikely to occur
+ in user-level code (in particular exception return, ldm rn, {...pc}^). */
+
static int
-condition_true (unsigned long cond, unsigned long status_reg)
+copy_block_xfer (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- if (cond == INST_AL || cond == INST_NV)
- return 1;
+ int load = bit (insn, 20);
+ int user = bit (insn, 22);
+ int increment = bit (insn, 23);
+ int before = bit (insn, 24);
+ int writeback = bit (insn, 21);
+ int rn = bits (insn, 16, 19);
+
+ /* Block transfers which don't mention PC can be run directly
+ out-of-line. */
+ if (rn != ARM_PC_REGNUM && (insn & 0x8000) == 0)
+ return copy_unmodified (gdbarch, insn, "ldm/stm", dsc);
+
+ if (rn == ARM_PC_REGNUM)
+ {
+ warning (_("displaced: Unpredictable LDM or STM with "
+ "base register r15"));
+ return copy_unmodified (gdbarch, insn, "unpredictable ldm/stm", dsc);
+ }
- switch (cond)
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying block transfer insn "
+ "%.8lx\n", (unsigned long) insn);
+
+ dsc->u.block.xfer_addr = displaced_read_reg (regs, dsc, rn);
+ dsc->u.block.rn = rn;
+
+ dsc->u.block.load = load;
+ dsc->u.block.user = user;
+ dsc->u.block.increment = increment;
+ dsc->u.block.before = before;
+ dsc->u.block.writeback = writeback;
+ dsc->u.block.cond = bits (insn, 28, 31);
+
+ dsc->u.block.regmask = insn & 0xffff;
+
+ if (load)
{
- case INST_EQ:
- return ((status_reg & FLAG_Z) != 0);
- case INST_NE:
- return ((status_reg & FLAG_Z) == 0);
- case INST_CS:
- return ((status_reg & FLAG_C) != 0);
- case INST_CC:
- return ((status_reg & FLAG_C) == 0);
- case INST_MI:
- return ((status_reg & FLAG_N) != 0);
- case INST_PL:
- return ((status_reg & FLAG_N) == 0);
- case INST_VS:
- return ((status_reg & FLAG_V) != 0);
- case INST_VC:
- return ((status_reg & FLAG_V) == 0);
- case INST_HI:
- return ((status_reg & (FLAG_C | FLAG_Z)) == FLAG_C);
- case INST_LS:
- return ((status_reg & (FLAG_C | FLAG_Z)) != FLAG_C);
- case INST_GE:
- return (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0));
- case INST_LT:
- return (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0));
- case INST_GT:
- return (((status_reg & FLAG_Z) == 0) &&
- (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0)));
- case INST_LE:
- return (((status_reg & FLAG_Z) != 0) ||
- (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0)));
+ if ((insn & 0xffff) == 0xffff)
+ {
+ /* LDM with a fully-populated register list. This case is
+ particularly tricky. Implement for now by fully emulating the
+ instruction (which might not behave perfectly in all cases, but
+ these instructions should be rare enough for that not to matter
+ too much). */
+ dsc->modinsn[0] = ARM_NOP;
+
+ dsc->cleanup = &cleanup_block_load_all;
+ }
+ else
+ {
+ /* LDM of a list of registers which includes PC. Implement by
+ rewriting the list of registers to be transferred into a
+ contiguous chunk r0...rX before doing the transfer, then shuffling
+ registers into the correct places in the cleanup routine. */
+ unsigned int regmask = insn & 0xffff;
+ unsigned int num_in_list = bitcount (regmask), new_regmask, bit = 1;
+ unsigned int to = 0, from = 0, i, new_rn;
+
+ for (i = 0; i < num_in_list; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, dsc, i);
+
+ /* Writeback makes things complicated. We need to avoid clobbering
+ the base register with one of the registers in our modified
+ register list, but just using a different register can't work in
+ all cases, e.g.:
+
+ ldm r14!, {r0-r13,pc}
+
+ which would need to be rewritten as:
+
+ ldm rN!, {r0-r14}
+
+ but that can't work, because there's no free register for N.
+
+ Solve this by turning off the writeback bit, and emulating
+ writeback manually in the cleanup routine. */
+
+ if (writeback)
+ insn &= ~(1 << 21);
+
+ new_regmask = (1 << num_in_list) - 1;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM r%d%s, "
+ "{..., pc}: original reg list %.4x, modified "
+ "list %.4x\n"), rn, writeback ? "!" : "",
+ (int) insn & 0xffff, new_regmask);
+
+ dsc->modinsn[0] = (insn & ~0xffff) | (new_regmask & 0xffff);
+
+ dsc->cleanup = &cleanup_block_load_pc;
+ }
}
- return 1;
+ else
+ {
+ /* STM of a list of registers which includes PC. Run the instruction
+ as-is, but out of line: this will store the wrong value for the PC,
+ so we must manually fix up the memory in the cleanup routine.
+ Doing things this way has the advantage that we can auto-detect
+ the offset of the PC write (which is architecture-dependent) in
+ the cleanup routine. */
+ dsc->modinsn[0] = insn;
+
+ dsc->cleanup = &cleanup_block_store_pc;
+ }
+
+ return 0;
}
-/* Support routines for single stepping. Calculate the next PC value. */
-#define submask(x) ((1L << ((x) + 1)) - 1)
-#define bit(obj,st) (((obj) >> (st)) & 1)
-#define bits(obj,st,fn) (((obj) >> (st)) & submask ((fn) - (st)))
-#define sbits(obj,st,fn) \
- ((long) (bits(obj,st,fn) | ((long) bit(obj,fn) * ~ submask (fn - st))))
-#define BranchDest(addr,instr) \
- ((CORE_ADDR) (((long) (addr)) + 8 + (sbits (instr, 0, 23) << 2)))
-#define ARM_PC_32 1
+/* Cleanup/copy SVC (SWI) instructions. These two functions are overridden
+ for Linux, where some SVC instructions must be treated specially. */
-static unsigned long
-shifted_reg_val (struct frame_info *frame, unsigned long inst, int carry,
- unsigned long pc_val, unsigned long status_reg)
-{
- unsigned long res, shift;
- int rm = bits (inst, 0, 3);
- unsigned long shifttype = bits (inst, 5, 6);
+static void
+cleanup_svc (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ CORE_ADDR resume_addr = dsc->insn_addr + 4;
- if (bit (inst, 4))
- {
- int rs = bits (inst, 8, 11);
- shift = (rs == 15 ? pc_val + 8
- : get_frame_register_unsigned (frame, rs)) & 0xFF;
- }
- else
- shift = bits (inst, 7, 11);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: cleanup for svc, resume at "
+ "%.8lx\n", (unsigned long) resume_addr);
- res = (rm == 15
- ? ((pc_val | (ARM_PC_32 ? 0 : status_reg))
- + (bit (inst, 4) ? 12 : 8))
- : get_frame_register_unsigned (frame, rm));
+ displaced_write_reg (regs, dsc, ARM_PC_REGNUM, resume_addr, BRANCH_WRITE_PC);
+}
- switch (shifttype)
- {
- case 0: /* LSL */
- res = shift >= 32 ? 0 : res << shift;
- break;
+static int
+copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ /* Allow OS-specific code to override SVC handling. */
+ if (dsc->u.svc.copy_svc_os)
+ return dsc->u.svc.copy_svc_os (gdbarch, insn, to, regs, dsc);
- case 1: /* LSR */
- res = shift >= 32 ? 0 : res >> shift;
- break;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying svc insn %.8lx\n",
+ (unsigned long) insn);
- case 2: /* ASR */
- if (shift >= 32)
- shift = 31;
- res = ((res & 0x80000000L)
- ? ~((~res) >> shift) : res >> shift);
- break;
+ /* Preparation: none.
+ Insn: unmodified svc.
+ Cleanup: pc <- insn_addr + 4. */
- case 3: /* ROR/RRX */
- shift &= 31;
- if (shift == 0)
- res = (res >> 1) | (carry ? 0x80000000L : 0);
- else
- res = (res >> shift) | (res << (32 - shift));
- break;
- }
+ dsc->modinsn[0] = insn;
- return res & 0xffffffff;
+ dsc->cleanup = &cleanup_svc;
+ /* Pretend we wrote to the PC, so cleanup doesn't set PC to the next
+ instruction. */
+ dsc->wrote_to_pc = 1;
+
+ return 0;
}
-/* Return number of 1-bits in VAL. */
+/* Copy undefined instructions. */
static int
-bitcount (unsigned long val)
+copy_undef (struct gdbarch *gdbarch, uint32_t insn,
+ struct displaced_step_closure *dsc)
{
- int nbits;
- for (nbits = 0; val != 0; nbits++)
- val &= val - 1; /* delete rightmost 1-bit in val */
- return nbits;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: copying undefined insn %.8lx\n",
+ (unsigned long) insn);
+
+ dsc->modinsn[0] = insn;
+
+ return 0;
}
-static CORE_ADDR
-thumb_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
+/* Copy unpredictable instructions. */
+
+static int
+copy_unpred (struct gdbarch *gdbarch, uint32_t insn,
+ struct displaced_step_closure *dsc)
{
- struct gdbarch *gdbarch = get_frame_arch (frame);
- unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
- unsigned short inst1 = read_memory_unsigned_integer (pc, 2);
- CORE_ADDR nextpc = pc + 2; /* default is next instruction */
- unsigned long offset;
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying unpredictable insn "
+ "%.8lx\n", (unsigned long) insn);
- if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
- {
- CORE_ADDR sp;
+ dsc->modinsn[0] = insn;
- /* Fetch the saved PC from the stack. It's stored above
- all of the other registers. */
- offset = bitcount (bits (inst1, 0, 7)) * INT_REGISTER_SIZE;
- sp = get_frame_register_unsigned (frame, ARM_SP_REGNUM);
- nextpc = (CORE_ADDR) read_memory_unsigned_integer (sp + offset, 4);
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- }
- else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
- {
- unsigned long status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
- unsigned long cond = bits (inst1, 8, 11);
- if (cond != 0x0f && condition_true (cond, status)) /* 0x0f = SWI */
- nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
- }
- else if ((inst1 & 0xf800) == 0xe000) /* unconditional branch */
- {
- nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
- }
- else if ((inst1 & 0xf800) == 0xf000) /* long branch with link, and blx */
- {
- unsigned short inst2 = read_memory_unsigned_integer (pc + 2, 2);
- offset = (sbits (inst1, 0, 10) << 12) + (bits (inst2, 0, 10) << 1);
- nextpc = pc_val + offset;
- /* For BLX make sure to clear the low bits. */
- if (bits (inst2, 11, 12) == 1)
- nextpc = nextpc & 0xfffffffc;
- }
- else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
+ return 0;
+}
+
+/* The decode_* functions are instruction decoding helpers. They mostly follow
+ the presentation in the ARM ARM. */
+
+static int
+decode_misc_memhint_neon (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int op1 = bits (insn, 20, 26), op2 = bits (insn, 4, 7);
+ unsigned int rn = bits (insn, 16, 19);
+
+ if (op1 == 0x10 && (op2 & 0x2) == 0x0 && (rn & 0xe) == 0x0)
+ return copy_unmodified (gdbarch, insn, "cps", dsc);
+ else if (op1 == 0x10 && op2 == 0x0 && (rn & 0xe) == 0x1)
+ return copy_unmodified (gdbarch, insn, "setend", dsc);
+ else if ((op1 & 0x60) == 0x20)
+ return copy_unmodified (gdbarch, insn, "neon dataproc", dsc);
+ else if ((op1 & 0x71) == 0x40)
+ return copy_unmodified (gdbarch, insn, "neon elt/struct load/store", dsc);
+ else if ((op1 & 0x77) == 0x41)
+ return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
+ else if ((op1 & 0x77) == 0x45)
+ return copy_preload (gdbarch, insn, regs, dsc); /* pli. */
+ else if ((op1 & 0x77) == 0x51)
{
- if (bits (inst1, 3, 6) == 0x0f)
- nextpc = pc_val;
+ if (rn != 0xf)
+ return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
else
- nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
-
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
+ return copy_unpred (gdbarch, insn, dsc);
}
-
- return nextpc;
+ else if ((op1 & 0x77) == 0x55)
+ return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
+ else if (op1 == 0x57)
+ switch (op2)
+ {
+ case 0x1: return copy_unmodified (gdbarch, insn, "clrex", dsc);
+ case 0x4: return copy_unmodified (gdbarch, insn, "dsb", dsc);
+ case 0x5: return copy_unmodified (gdbarch, insn, "dmb", dsc);
+ case 0x6: return copy_unmodified (gdbarch, insn, "isb", dsc);
+ default: return copy_unpred (gdbarch, insn, dsc);
+ }
+ else if ((op1 & 0x63) == 0x43)
+ return copy_unpred (gdbarch, insn, dsc);
+ else if ((op2 & 0x1) == 0x0)
+ switch (op1 & ~0x80)
+ {
+ case 0x61:
+ return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
+ case 0x65:
+ return copy_preload_reg (gdbarch, insn, regs, dsc); /* pli reg. */
+ case 0x71: case 0x75:
+ /* pld/pldw reg. */
+ return copy_preload_reg (gdbarch, insn, regs, dsc);
+ case 0x63: case 0x67: case 0x73: case 0x77:
+ return copy_unpred (gdbarch, insn, dsc);
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+ else
+ return copy_undef (gdbarch, insn, dsc); /* Probably unreachable. */
}
-CORE_ADDR
-arm_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
+static int
+decode_unconditional (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
{
- struct gdbarch *gdbarch = get_frame_arch (frame);
- unsigned long pc_val;
- unsigned long this_instr;
- unsigned long status;
- CORE_ADDR nextpc;
+ if (bit (insn, 27) == 0)
+ return decode_misc_memhint_neon (gdbarch, insn, regs, dsc);
+ /* Switch on bits: 0bxxxxx321xxx0xxxxxxxxxxxxxxxxxxxx. */
+ else switch (((insn & 0x7000000) >> 23) | ((insn & 0x100000) >> 20))
+ {
+ case 0x0: case 0x2:
+ return copy_unmodified (gdbarch, insn, "srs", dsc);
- if (arm_pc_is_thumb (pc))
- return thumb_get_next_pc (frame, pc);
+ case 0x1: case 0x3:
+ return copy_unmodified (gdbarch, insn, "rfe", dsc);
- pc_val = (unsigned long) pc;
- this_instr = read_memory_unsigned_integer (pc, 4);
- status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
- nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
+ case 0x4: case 0x5: case 0x6: case 0x7:
+ return copy_b_bl_blx (gdbarch, insn, regs, dsc);
- if (bits (this_instr, 28, 31) == INST_NV)
- switch (bits (this_instr, 24, 27))
- {
- case 0xa:
- case 0xb:
+ case 0x8:
+ switch ((insn & 0xe00000) >> 21)
{
- /* Branch with Link and change to Thumb. */
- nextpc = BranchDest (pc, this_instr);
- nextpc |= bit (this_instr, 24) << 1;
+ case 0x1: case 0x3: case 0x4: case 0x5: case 0x6: case 0x7:
+ /* stc/stc2. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- break;
- }
- case 0xc:
- case 0xd:
- case 0xe:
- /* Coprocessor register transfer. */
- if (bits (this_instr, 12, 15) == 15)
- error (_("Invalid update to pc in instruction"));
- break;
- }
- else if (condition_true (bits (this_instr, 28, 31), status))
- {
- switch (bits (this_instr, 24, 27))
- {
- case 0x0:
- case 0x1: /* data processing */
case 0x2:
- case 0x3:
+ return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
+
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+
+ case 0x9:
+ {
+ int rn_f = (bits (insn, 16, 19) == 0xf);
+ switch ((insn & 0xe00000) >> 21)
{
- unsigned long operand1, operand2, result = 0;
- unsigned long rn;
- int c;
+ case 0x1: case 0x3:
+ /* ldc/ldc2 imm (undefined for rn == pc). */
+ return rn_f ? copy_undef (gdbarch, insn, dsc)
+ : copy_copro_load_store (gdbarch, insn, regs, dsc);
- if (bits (this_instr, 12, 15) != 15)
- break;
+ case 0x2:
+ return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
- if (bits (this_instr, 22, 25) == 0
- && bits (this_instr, 4, 7) == 9) /* multiply */
- error (_("Invalid update to pc in instruction"));
+ case 0x4: case 0x5: case 0x6: case 0x7:
+ /* ldc/ldc2 lit (undefined for rn != pc). */
+ return rn_f ? copy_copro_load_store (gdbarch, insn, regs, dsc)
+ : copy_undef (gdbarch, insn, dsc);
- /* BX <reg>, BLX <reg> */
- if (bits (this_instr, 4, 27) == 0x12fff1
- || bits (this_instr, 4, 27) == 0x12fff3)
- {
- rn = bits (this_instr, 0, 3);
- result = (rn == 15) ? pc_val + 8
- : get_frame_register_unsigned (frame, rn);
- nextpc = (CORE_ADDR) gdbarch_addr_bits_remove
- (gdbarch, result);
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+ }
- if (nextpc == pc)
- error (_("Infinite loop detected"));
+ case 0xa:
+ return copy_unmodified (gdbarch, insn, "stc/stc2", dsc);
- return nextpc;
- }
+ case 0xb:
+ if (bits (insn, 16, 19) == 0xf)
+ /* ldc/ldc2 lit. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
- /* Multiply into PC */
- c = (status & FLAG_C) ? 1 : 0;
- rn = bits (this_instr, 16, 19);
- operand1 = (rn == 15) ? pc_val + 8
- : get_frame_register_unsigned (frame, rn);
+ case 0xc:
+ if (bit (insn, 4))
+ return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
- if (bit (this_instr, 25))
- {
- unsigned long immval = bits (this_instr, 0, 7);
- unsigned long rotate = 2 * bits (this_instr, 8, 11);
- operand2 = ((immval >> rotate) | (immval << (32 - rotate)))
- & 0xffffffff;
- }
- else /* operand 2 is a shifted register */
- operand2 = shifted_reg_val (frame, this_instr, c, pc_val, status);
+ case 0xd:
+ if (bit (insn, 4))
+ return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
- switch (bits (this_instr, 21, 24))
- {
- case 0x0: /*and */
- result = operand1 & operand2;
- break;
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+}
- case 0x1: /*eor */
- result = operand1 ^ operand2;
- break;
+/* Decode miscellaneous instructions in dp/misc encoding space. */
- case 0x2: /*sub */
- result = operand1 - operand2;
- break;
+static int
+decode_miscellaneous (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int op2 = bits (insn, 4, 6);
+ unsigned int op = bits (insn, 21, 22);
+ unsigned int op1 = bits (insn, 16, 19);
- case 0x3: /*rsb */
- result = operand2 - operand1;
- break;
+ switch (op2)
+ {
+ case 0x0:
+ return copy_unmodified (gdbarch, insn, "mrs/msr", dsc);
+
+ case 0x1:
+ if (op == 0x1) /* bx. */
+ return copy_bx_blx_reg (gdbarch, insn, regs, dsc);
+ else if (op == 0x3)
+ return copy_unmodified (gdbarch, insn, "clz", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
- case 0x4: /*add */
- result = operand1 + operand2;
- break;
+ case 0x2:
+ if (op == 0x1)
+ /* Not really supported. */
+ return copy_unmodified (gdbarch, insn, "bxj", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
- case 0x5: /*adc */
- result = operand1 + operand2 + c;
- break;
+ case 0x3:
+ if (op == 0x1)
+ return copy_bx_blx_reg (gdbarch, insn,
+ regs, dsc); /* blx register. */
+ else
+ return copy_undef (gdbarch, insn, dsc);
- case 0x6: /*sbc */
- result = operand1 - operand2 + c;
- break;
+ case 0x5:
+ return copy_unmodified (gdbarch, insn, "saturating add/sub", dsc);
- case 0x7: /*rsc */
- result = operand2 - operand1 + c;
- break;
+ case 0x7:
+ if (op == 0x1)
+ return copy_unmodified (gdbarch, insn, "bkpt", dsc);
+ else if (op == 0x3)
+ /* Not really supported. */
+ return copy_unmodified (gdbarch, insn, "smc", dsc);
- case 0x8:
- case 0x9:
- case 0xa:
- case 0xb: /* tst, teq, cmp, cmn */
- result = (unsigned long) nextpc;
- break;
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+}
- case 0xc: /*orr */
- result = operand1 | operand2;
- break;
+static int
+decode_dp_misc (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ if (bit (insn, 25))
+ switch (bits (insn, 20, 24))
+ {
+ case 0x10:
+ return copy_unmodified (gdbarch, insn, "movw", dsc);
- case 0xd: /*mov */
- /* Always step into a function. */
- result = operand2;
- break;
+ case 0x14:
+ return copy_unmodified (gdbarch, insn, "movt", dsc);
- case 0xe: /*bic */
- result = operand1 & ~operand2;
- break;
+ case 0x12: case 0x16:
+ return copy_unmodified (gdbarch, insn, "msr imm", dsc);
- case 0xf: /*mvn */
- result = ~operand2;
- break;
- }
- nextpc = (CORE_ADDR) gdbarch_addr_bits_remove
- (gdbarch, result);
+ default:
+ return copy_alu_imm (gdbarch, insn, regs, dsc);
+ }
+ else
+ {
+ uint32_t op1 = bits (insn, 20, 24), op2 = bits (insn, 4, 7);
+
+ if ((op1 & 0x19) != 0x10 && (op2 & 0x1) == 0x0)
+ return copy_alu_reg (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) != 0x10 && (op2 & 0x9) == 0x1)
+ return copy_alu_shifted_reg (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) == 0x10 && (op2 & 0x8) == 0x0)
+ return decode_miscellaneous (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) == 0x10 && (op2 & 0x9) == 0x8)
+ return copy_unmodified (gdbarch, insn, "halfword mul/mla", dsc);
+ else if ((op1 & 0x10) == 0x00 && op2 == 0x9)
+ return copy_unmodified (gdbarch, insn, "mul/mla", dsc);
+ else if ((op1 & 0x10) == 0x10 && op2 == 0x9)
+ return copy_unmodified (gdbarch, insn, "synch", dsc);
+ else if (op2 == 0xb || (op2 & 0xd) == 0xd)
+ /* 2nd arg means "unpriveleged". */
+ return copy_extra_ld_st (gdbarch, insn, (op1 & 0x12) == 0x02, regs,
+ dsc);
+ }
+
+ /* Should be unreachable. */
+ return 1;
+}
+
+static int
+decode_ld_st_word_ubyte (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int a = bit (insn, 25), b = bit (insn, 4);
+ uint32_t op1 = bits (insn, 20, 24);
+ int rn_f = bits (insn, 16, 19) == 0xf;
+
+ if ((!a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02)
+ || (a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 0);
+ else if ((!a && (op1 & 0x17) == 0x02)
+ || (a && (op1 & 0x17) == 0x02 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 1);
+ else if ((!a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03)
+ || (a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 0);
+ else if ((!a && (op1 & 0x17) == 0x03)
+ || (a && (op1 & 0x17) == 0x03 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 1);
+ else if ((!a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06)
+ || (a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 0);
+ else if ((!a && (op1 & 0x17) == 0x06)
+ || (a && (op1 & 0x17) == 0x06 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 1);
+ else if ((!a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07)
+ || (a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 0);
+ else if ((!a && (op1 & 0x17) == 0x07)
+ || (a && (op1 & 0x17) == 0x07 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 1);
+
+ /* Should be unreachable. */
+ return 1;
+}
+
+static int
+decode_media (struct gdbarch *gdbarch, uint32_t insn,
+ struct displaced_step_closure *dsc)
+{
+ switch (bits (insn, 20, 24))
+ {
+ case 0x00: case 0x01: case 0x02: case 0x03:
+ return copy_unmodified (gdbarch, insn, "parallel add/sub signed", dsc);
+
+ case 0x04: case 0x05: case 0x06: case 0x07:
+ return copy_unmodified (gdbarch, insn, "parallel add/sub unsigned", dsc);
+
+ case 0x08: case 0x09: case 0x0a: case 0x0b:
+ case 0x0c: case 0x0d: case 0x0e: case 0x0f:
+ return copy_unmodified (gdbarch, insn,
+ "decode/pack/unpack/saturate/reverse", dsc);
+
+ case 0x18:
+ if (bits (insn, 5, 7) == 0) /* op2. */
+ {
+ if (bits (insn, 12, 15) == 0xf)
+ return copy_unmodified (gdbarch, insn, "usad8", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "usada8", dsc);
+ }
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x1a: case 0x1b:
+ if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
+ return copy_unmodified (gdbarch, insn, "sbfx", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x1c: case 0x1d:
+ if (bits (insn, 5, 6) == 0x0) /* op2[1:0]. */
+ {
+ if (bits (insn, 0, 3) == 0xf)
+ return copy_unmodified (gdbarch, insn, "bfc", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "bfi", dsc);
+ }
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x1e: case 0x1f:
+ if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
+ return copy_unmodified (gdbarch, insn, "ubfx", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
+ }
+
+ /* Should be unreachable. */
+ return 1;
+}
+
+static int
+decode_b_bl_ldmstm (struct gdbarch *gdbarch, int32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ if (bit (insn, 25))
+ return copy_b_bl_blx (gdbarch, insn, regs, dsc);
+ else
+ return copy_block_xfer (gdbarch, insn, regs, dsc);
+}
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- break;
- }
+static int
+decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int opcode = bits (insn, 20, 24);
- case 0x4:
- case 0x5: /* data transfer */
- case 0x6:
- case 0x7:
- if (bit (this_instr, 20))
- {
- /* load */
- if (bits (this_instr, 12, 15) == 15)
- {
- /* rd == pc */
- unsigned long rn;
- unsigned long base;
+ switch (opcode)
+ {
+ case 0x04: case 0x05: /* VFP/Neon mrrc/mcrr. */
+ return copy_unmodified (gdbarch, insn, "vfp/neon mrrc/mcrr", dsc);
+
+ case 0x08: case 0x0a: case 0x0c: case 0x0e:
+ case 0x12: case 0x16:
+ return copy_unmodified (gdbarch, insn, "vfp/neon vstm/vpush", dsc);
+
+ case 0x09: case 0x0b: case 0x0d: case 0x0f:
+ case 0x13: case 0x17:
+ return copy_unmodified (gdbarch, insn, "vfp/neon vldm/vpop", dsc);
+
+ case 0x10: case 0x14: case 0x18: case 0x1c: /* vstr. */
+ case 0x11: case 0x15: case 0x19: case 0x1d: /* vldr. */
+ /* Note: no writeback for these instructions. Bit 25 will always be
+ zero though (via caller), so the following works OK. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ }
- if (bit (this_instr, 22))
- error (_("Invalid update to pc in instruction"));
+ /* Should be unreachable. */
+ return 1;
+}
- /* byte write to PC */
- rn = bits (this_instr, 16, 19);
- base = (rn == 15) ? pc_val + 8
- : get_frame_register_unsigned (frame, rn);
- if (bit (this_instr, 24))
- {
- /* pre-indexed */
- int c = (status & FLAG_C) ? 1 : 0;
- unsigned long offset =
- (bit (this_instr, 25)
- ? shifted_reg_val (frame, this_instr, c, pc_val, status)
- : bits (this_instr, 0, 11));
+static int
+decode_svc_copro (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int op1 = bits (insn, 20, 25);
+ int op = bit (insn, 4);
+ unsigned int coproc = bits (insn, 8, 11);
+ unsigned int rn = bits (insn, 16, 19);
+
+ if ((op1 & 0x20) == 0x00 && (op1 & 0x3a) != 0x00 && (coproc & 0xe) == 0xa)
+ return decode_ext_reg_ld_st (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x21) == 0x00 && (op1 & 0x3a) != 0x00
+ && (coproc & 0xe) != 0xa)
+ /* stc/stc2. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x21) == 0x01 && (op1 & 0x3a) != 0x00
+ && (coproc & 0xe) != 0xa)
+ /* ldc/ldc2 imm/lit. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x3e) == 0x00)
+ return copy_undef (gdbarch, insn, dsc);
+ else if ((op1 & 0x3e) == 0x04 && (coproc & 0xe) == 0xa)
+ return copy_unmodified (gdbarch, insn, "neon 64bit xfer", dsc);
+ else if (op1 == 0x04 && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
+ else if (op1 == 0x05 && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
+ else if ((op1 & 0x30) == 0x20 && !op)
+ {
+ if ((coproc & 0xe) == 0xa)
+ return copy_unmodified (gdbarch, insn, "vfp dataproc", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
+ }
+ else if ((op1 & 0x30) == 0x20 && op)
+ return copy_unmodified (gdbarch, insn, "neon 8/16/32 bit xfer", dsc);
+ else if ((op1 & 0x31) == 0x20 && op && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
+ else if ((op1 & 0x31) == 0x21 && op && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
+ else if ((op1 & 0x30) == 0x30)
+ return copy_svc (gdbarch, insn, to, regs, dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc); /* Possibly unreachable. */
+}
- if (bit (this_instr, 23))
- base += offset;
- else
- base -= offset;
- }
- nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base,
- 4);
+static void
+thumb_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
+ CORE_ADDR to, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ error (_("Displaced stepping is only supported in ARM mode"));
+}
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
+void
+arm_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
+ CORE_ADDR to, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int err = 0;
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ uint32_t insn;
+
+ /* Most displaced instructions use a 1-instruction scratch space, so set this
+ here and override below if/when necessary. */
+ dsc->numinsns = 1;
+ dsc->insn_addr = from;
+ dsc->scratch_base = to;
+ dsc->cleanup = NULL;
+ dsc->wrote_to_pc = 0;
+
+ if (!displaced_in_arm_mode (regs))
+ return thumb_process_displaced_insn (gdbarch, from, to, regs, dsc);
+
+ dsc->is_thumb = 0;
+ dsc->insn_size = 4;
+ insn = read_memory_unsigned_integer (from, 4, byte_order_for_code);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: stepping insn %.8lx "
+ "at %.8lx\n", (unsigned long) insn,
+ (unsigned long) from);
+
+ if ((insn & 0xf0000000) == 0xf0000000)
+ err = decode_unconditional (gdbarch, insn, regs, dsc);
+ else switch (((insn & 0x10) >> 4) | ((insn & 0xe000000) >> 24))
+ {
+ case 0x0: case 0x1: case 0x2: case 0x3:
+ err = decode_dp_misc (gdbarch, insn, regs, dsc);
+ break;
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- }
- }
- break;
+ case 0x4: case 0x5: case 0x6:
+ err = decode_ld_st_word_ubyte (gdbarch, insn, regs, dsc);
+ break;
- case 0x8:
- case 0x9: /* block transfer */
- if (bit (this_instr, 20))
- {
- /* LDM */
- if (bit (this_instr, 15))
- {
- /* loading pc */
- int offset = 0;
+ case 0x7:
+ err = decode_media (gdbarch, insn, dsc);
+ break;
- if (bit (this_instr, 23))
- {
- /* up */
- unsigned long reglist = bits (this_instr, 0, 14);
- offset = bitcount (reglist) * 4;
- if (bit (this_instr, 24)) /* pre */
- offset += 4;
- }
- else if (bit (this_instr, 24))
- offset = -4;
+ case 0x8: case 0x9: case 0xa: case 0xb:
+ err = decode_b_bl_ldmstm (gdbarch, insn, regs, dsc);
+ break;
- {
- unsigned long rn_val =
- get_frame_register_unsigned (frame,
- bits (this_instr, 16, 19));
- nextpc =
- (CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val
- + offset),
- 4);
- }
- nextpc = gdbarch_addr_bits_remove
- (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- }
- }
- break;
+ case 0xc: case 0xd: case 0xe: case 0xf:
+ err = decode_svc_copro (gdbarch, insn, to, regs, dsc);
+ break;
+ }
- case 0xb: /* branch & link */
- case 0xa: /* branch */
- {
- nextpc = BranchDest (pc, this_instr);
+ if (err)
+ internal_error (__FILE__, __LINE__,
+ _("arm_process_displaced_insn: Instruction decode error"));
+}
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- break;
- }
+/* Actually set up the scratch space for a displaced instruction. */
- case 0xc:
- case 0xd:
- case 0xe: /* coproc ops */
- case 0xf: /* SWI */
- break;
+void
+arm_displaced_init_closure (struct gdbarch *gdbarch, CORE_ADDR from,
+ CORE_ADDR to, struct displaced_step_closure *dsc)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ unsigned int i, len, offset;
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ int size = dsc->is_thumb? 2 : 4;
+ const unsigned char *bkp_insn;
+
+ offset = 0;
+ /* Poke modified instruction(s). */
+ for (i = 0; i < dsc->numinsns; i++)
+ {
+ if (debug_displaced)
+ {
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing insn ");
+ if (size == 4)
+ fprintf_unfiltered (gdb_stdlog, "%.8lx",
+ dsc->modinsn[i]);
+ else if (size == 2)
+ fprintf_unfiltered (gdb_stdlog, "%.4x",
+ (unsigned short)dsc->modinsn[i]);
+
+ fprintf_unfiltered (gdb_stdlog, " at %.8lx\n",
+ (unsigned long) to + offset);
- default:
- fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n"));
- return (pc);
}
+ write_memory_unsigned_integer (to + offset, size,
+ byte_order_for_code,
+ dsc->modinsn[i]);
+ offset += size;
}
- return nextpc;
+ /* Choose the correct breakpoint instruction. */
+ if (dsc->is_thumb)
+ {
+ bkp_insn = tdep->thumb_breakpoint;
+ len = tdep->thumb_breakpoint_size;
+ }
+ else
+ {
+ bkp_insn = tdep->arm_breakpoint;
+ len = tdep->arm_breakpoint_size;
+ }
+
+ /* Put breakpoint afterwards. */
+ write_memory (to + offset, bkp_insn, len);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copy %s->%s: ",
+ paddress (gdbarch, from), paddress (gdbarch, to));
}
-/* single_step() is called just before we want to resume the inferior,
- if we want to single-step it but there is no hardware or kernel
- single-step support. We find the target of the coming instruction
- and breakpoint it. */
+/* Entry point for copying an instruction into scratch space for displaced
+ stepping. */
-int
-arm_software_single_step (struct frame_info *frame)
+struct displaced_step_closure *
+arm_displaced_step_copy_insn (struct gdbarch *gdbarch,
+ CORE_ADDR from, CORE_ADDR to,
+ struct regcache *regs)
{
- /* NOTE: This may insert the wrong breakpoint instruction when
- single-stepping over a mode-changing instruction, if the
- CPSR heuristics are used. */
+ struct displaced_step_closure *dsc
+ = xmalloc (sizeof (struct displaced_step_closure));
+ arm_process_displaced_insn (gdbarch, from, to, regs, dsc);
+ arm_displaced_init_closure (gdbarch, from, to, dsc);
- CORE_ADDR next_pc = arm_get_next_pc (frame, get_frame_pc (frame));
- insert_single_step_breakpoint (next_pc);
+ return dsc;
+}
+
+/* Entry point for cleaning things up after a displaced instruction has been
+ single-stepped. */
+
+void
+arm_displaced_step_fixup (struct gdbarch *gdbarch,
+ struct displaced_step_closure *dsc,
+ CORE_ADDR from, CORE_ADDR to,
+ struct regcache *regs)
+{
+ if (dsc->cleanup)
+ dsc->cleanup (gdbarch, regs, dsc);
+
+ if (!dsc->wrote_to_pc)
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM,
+ dsc->insn_addr + dsc->insn_size);
- return 1;
}
#include "bfd-in2.h"
static int
gdb_print_insn_arm (bfd_vma memaddr, disassemble_info *info)
{
- if (arm_pc_is_thumb (memaddr))
+ struct gdbarch *gdbarch = info->application_data;
+
+ if (arm_pc_is_thumb (gdbarch, memaddr))
{
static asymbol *asym;
static combined_entry_type ce;
1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
C C C C 0 1 1 x x x x x x x x x x x x x x x x x x x x 1 x x x x
- Even this may only true if the condition predicate is true. The
+ Even this may only true if the condition predicate is true. The
following use a condition predicate of ALWAYS so it is always TRUE.
There are other ways of forcing a breakpoint. GNU/Linux, RISC iX,
arm_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr, int *lenptr)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
- if (arm_pc_is_thumb (*pcptr))
+ if (arm_pc_is_thumb (gdbarch, *pcptr))
{
*pcptr = UNMAKE_THUMB_ADDR (*pcptr);
+
+ /* If we have a separate 32-bit breakpoint instruction for Thumb-2,
+ check whether we are replacing a 32-bit instruction. */
+ if (tdep->thumb2_breakpoint != NULL)
+ {
+ gdb_byte buf[2];
+ if (target_read_memory (*pcptr, buf, 2) == 0)
+ {
+ unsigned short inst1;
+ inst1 = extract_unsigned_integer (buf, 2, byte_order_for_code);
+ if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
+ {
+ *lenptr = tdep->thumb2_breakpoint_size;
+ return tdep->thumb2_breakpoint;
+ }
+ }
+ }
+
*lenptr = tdep->thumb_breakpoint_size;
return tdep->thumb_breakpoint;
}
}
}
+static void
+arm_remote_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr,
+ int *kindptr)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ arm_breakpoint_from_pc (gdbarch, pcptr, kindptr);
+
+ if (arm_pc_is_thumb (gdbarch, *pcptr) && *kindptr == 4)
+ /* The documented magic value for a 32-bit Thumb-2 breakpoint, so
+ that this is not confused with a 32-bit ARM breakpoint. */
+ *kindptr = 3;
+}
+
/* Extract from an array REGBUF containing the (raw) register state a
function return value of type TYPE, and copy that, in virtual
format, into VALBUF. */
gdb_byte *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regs);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
if (TYPE_CODE_FLT == TYPE_CODE (type))
{
case ARM_FLOAT_SOFT_FPA:
case ARM_FLOAT_SOFT_VFP:
+ /* ARM_FLOAT_VFP can arise if this is a variadic function so
+ not using the VFP ABI code. */
+ case ARM_FLOAT_VFP:
regcache_cooked_read (regs, ARM_A1_REGNUM, valbuf);
if (TYPE_LENGTH (type) > 4)
regcache_cooked_read (regs, ARM_A1_REGNUM + 1,
break;
default:
- internal_error
- (__FILE__, __LINE__,
- _("arm_extract_return_value: Floating point model not supported"));
+ internal_error (__FILE__, __LINE__,
+ _("arm_extract_return_value: "
+ "Floating point model not supported"));
break;
}
}
|| TYPE_CODE (type) == TYPE_CODE_REF
|| TYPE_CODE (type) == TYPE_CODE_ENUM)
{
- /* If the the type is a plain integer, then the access is
- straight-forward. Otherwise we have to play around a bit more. */
+ /* If the type is a plain integer, then the access is
+ straight-forward. Otherwise we have to play around a bit
+ more. */
int len = TYPE_LENGTH (type);
int regno = ARM_A1_REGNUM;
ULONGEST tmp;
store_unsigned_integer (valbuf,
(len > INT_REGISTER_SIZE
? INT_REGISTER_SIZE : len),
- tmp);
+ byte_order, tmp);
len -= INT_REGISTER_SIZE;
valbuf += INT_REGISTER_SIZE;
}
for (i = 0; i < TYPE_NFIELDS (type); i++)
{
enum type_code field_type_code;
- field_type_code = TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type, i)));
+ field_type_code = TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type,
+ i)));
/* Is it a floating point type field? */
if (field_type_code == TYPE_CODE_FLT)
const gdb_byte *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regs);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
if (TYPE_CODE (type) == TYPE_CODE_FLT)
{
case ARM_FLOAT_SOFT_FPA:
case ARM_FLOAT_SOFT_VFP:
+ /* ARM_FLOAT_VFP can arise if this is a variadic function so
+ not using the VFP ABI code. */
+ case ARM_FLOAT_VFP:
regcache_cooked_write (regs, ARM_A1_REGNUM, valbuf);
if (TYPE_LENGTH (type) > 4)
regcache_cooked_write (regs, ARM_A1_REGNUM + 1,
break;
default:
- internal_error
- (__FILE__, __LINE__,
- _("arm_store_return_value: Floating point model not supported"));
+ internal_error (__FILE__, __LINE__,
+ _("arm_store_return_value: Floating "
+ "point model not supported"));
break;
}
}
bfd_byte tmpbuf[INT_REGISTER_SIZE];
LONGEST val = unpack_long (type, valbuf);
- store_signed_integer (tmpbuf, INT_REGISTER_SIZE, val);
+ store_signed_integer (tmpbuf, INT_REGISTER_SIZE, byte_order, val);
regcache_cooked_write (regs, ARM_A1_REGNUM, tmpbuf);
}
else
gdb_byte *readbuf, const gdb_byte *writebuf)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum arm_vfp_cprc_base_type vfp_base_type;
+ int vfp_base_count;
+
+ if (arm_vfp_abi_for_function (gdbarch, func_type)
+ && arm_vfp_call_candidate (valtype, &vfp_base_type, &vfp_base_count))
+ {
+ int reg_char = arm_vfp_cprc_reg_char (vfp_base_type);
+ int unit_length = arm_vfp_cprc_unit_length (vfp_base_type);
+ int i;
+ for (i = 0; i < vfp_base_count; i++)
+ {
+ if (reg_char == 'q')
+ {
+ if (writebuf)
+ arm_neon_quad_write (gdbarch, regcache, i,
+ writebuf + i * unit_length);
+
+ if (readbuf)
+ arm_neon_quad_read (gdbarch, regcache, i,
+ readbuf + i * unit_length);
+ }
+ else
+ {
+ char name_buf[4];
+ int regnum;
+
+ sprintf (name_buf, "%c%d", reg_char, i);
+ regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ if (writebuf)
+ regcache_cooked_write (regcache, regnum,
+ writebuf + i * unit_length);
+ if (readbuf)
+ regcache_cooked_read (regcache, regnum,
+ readbuf + i * unit_length);
+ }
+ }
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
if (TYPE_CODE (valtype) == TYPE_CODE_STRUCT
|| TYPE_CODE (valtype) == TYPE_CODE_UNION
static int
arm_get_longjmp_target (struct frame_info *frame, CORE_ADDR *pc)
{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR jb_addr;
char buf[INT_REGISTER_SIZE];
- struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (frame));
jb_addr = get_frame_register_unsigned (frame, ARM_A1_REGNUM);
INT_REGISTER_SIZE))
return 0;
- *pc = extract_unsigned_integer (buf, INT_REGISTER_SIZE);
+ *pc = extract_unsigned_integer (buf, INT_REGISTER_SIZE, byte_order);
return 1;
}
/* If PC is in a Thumb call or return stub, return the address of the
target PC, which is in a register. The thunk functions are called
_call_via_xx, where x is the register name. The possible names
- are r0-r9, sl, fp, ip, sp, and lr. */
- if (strncmp (name, "_call_via_", 10) == 0)
+ are r0-r9, sl, fp, ip, sp, and lr. ARM RealView has similar
+ functions, named __ARM_call_via_r[0-7]. */
+ if (strncmp (name, "_call_via_", 10) == 0
+ || strncmp (name, "__ARM_call_via_", strlen ("__ARM_call_via_")) == 0)
{
/* Use the name suffix to determine which register contains the
target PC. */
struct gdbarch_info info;
/* If the current architecture is not ARM, we have nothing to do. */
- if (gdbarch_bfd_arch_info (current_gdbarch)->arch != bfd_arch_arm)
+ if (gdbarch_bfd_arch_info (target_gdbarch)->arch != bfd_arch_arm)
return;
/* Update the architecture. */
gdbarch_info_init (&info);
if (!gdbarch_update_p (info))
- internal_error (__FILE__, __LINE__, "could not update architecture");
+ internal_error (__FILE__, __LINE__, _("could not update architecture"));
}
static void
show_fp_model (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
- struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
if (arm_fp_model == ARM_FLOAT_AUTO
- && gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
+ && gdbarch_bfd_arch_info (target_gdbarch)->arch == bfd_arch_arm)
fprintf_filtered (file, _("\
The current ARM floating point model is \"auto\" (currently \"%s\").\n"),
fp_model_strings[tdep->fp_model]);
arm_show_abi (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
- struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
if (arm_abi_global == ARM_ABI_AUTO
- && gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
+ && gdbarch_bfd_arch_info (target_gdbarch)->arch == bfd_arch_arm)
fprintf_filtered (file, _("\
The current ARM ABI is \"auto\" (currently \"%s\").\n"),
arm_abi_strings[tdep->arm_abi]);
arm_abi_string);
}
+static void
+arm_show_fallback_mode (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
+
+ fprintf_filtered (file,
+ _("The current execution mode assumed "
+ "(when symbols are unavailable) is \"%s\".\n"),
+ arm_fallback_mode_string);
+}
+
+static void
+arm_show_force_mode (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
+
+ fprintf_filtered (file,
+ _("The current execution mode assumed "
+ "(even when symbols are available) is \"%s\".\n"),
+ arm_force_mode_string);
+}
+
/* If the user changes the register disassembly style used for info
register and other commands, we have to also switch the style used
in opcodes for disassembly output. This function is run in the "set
static const char *
arm_register_name (struct gdbarch *gdbarch, int i)
{
+ const int num_regs = gdbarch_num_regs (gdbarch);
+
+ if (gdbarch_tdep (gdbarch)->have_vfp_pseudos
+ && i >= num_regs && i < num_regs + 32)
+ {
+ static const char *const vfp_pseudo_names[] = {
+ "s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
+ "s8", "s9", "s10", "s11", "s12", "s13", "s14", "s15",
+ "s16", "s17", "s18", "s19", "s20", "s21", "s22", "s23",
+ "s24", "s25", "s26", "s27", "s28", "s29", "s30", "s31",
+ };
+
+ return vfp_pseudo_names[i - num_regs];
+ }
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos
+ && i >= num_regs + 32 && i < num_regs + 32 + 16)
+ {
+ static const char *const neon_pseudo_names[] = {
+ "q0", "q1", "q2", "q3", "q4", "q5", "q6", "q7",
+ "q8", "q9", "q10", "q11", "q12", "q13", "q14", "q15",
+ };
+
+ return neon_pseudo_names[i - num_regs - 32];
+ }
+
if (i >= ARRAY_SIZE (arm_register_names))
/* These registers are only supported on targets which supply
an XML description. */
set_arm_regname_option (current);
}
-/* Test whether the coff symbol specific value corresponds to a Thumb
- function. */
+/* Test whether the coff symbol specific value corresponds to a Thumb
+ function. */
+
+static int
+coff_sym_is_thumb (int val)
+{
+ return (val == C_THUMBEXT
+ || val == C_THUMBSTAT
+ || val == C_THUMBEXTFUNC
+ || val == C_THUMBSTATFUNC
+ || val == C_THUMBLABEL);
+}
+
+/* arm_coff_make_msymbol_special()
+ arm_elf_make_msymbol_special()
+
+ These functions test whether the COFF or ELF symbol corresponds to
+ an address in thumb code, and set a "special" bit in a minimal
+ symbol to indicate that it does. */
+
+static void
+arm_elf_make_msymbol_special(asymbol *sym, struct minimal_symbol *msym)
+{
+ /* Thumb symbols are of type STT_LOPROC, (synonymous with
+ STT_ARM_TFUNC). */
+ if (ELF_ST_TYPE (((elf_symbol_type *)sym)->internal_elf_sym.st_info)
+ == STT_LOPROC)
+ MSYMBOL_SET_SPECIAL (msym);
+}
+
+static void
+arm_coff_make_msymbol_special(int val, struct minimal_symbol *msym)
+{
+ if (coff_sym_is_thumb (val))
+ MSYMBOL_SET_SPECIAL (msym);
+}
+
+static void
+arm_objfile_data_free (struct objfile *objfile, void *arg)
+{
+ struct arm_per_objfile *data = arg;
+ unsigned int i;
+
+ for (i = 0; i < objfile->obfd->section_count; i++)
+ VEC_free (arm_mapping_symbol_s, data->section_maps[i]);
+}
+
+static void
+arm_record_special_symbol (struct gdbarch *gdbarch, struct objfile *objfile,
+ asymbol *sym)
+{
+ const char *name = bfd_asymbol_name (sym);
+ struct arm_per_objfile *data;
+ VEC(arm_mapping_symbol_s) **map_p;
+ struct arm_mapping_symbol new_map_sym;
+
+ gdb_assert (name[0] == '$');
+ if (name[1] != 'a' && name[1] != 't' && name[1] != 'd')
+ return;
+
+ data = objfile_data (objfile, arm_objfile_data_key);
+ if (data == NULL)
+ {
+ data = OBSTACK_ZALLOC (&objfile->objfile_obstack,
+ struct arm_per_objfile);
+ set_objfile_data (objfile, arm_objfile_data_key, data);
+ data->section_maps = OBSTACK_CALLOC (&objfile->objfile_obstack,
+ objfile->obfd->section_count,
+ VEC(arm_mapping_symbol_s) *);
+ }
+ map_p = &data->section_maps[bfd_get_section (sym)->index];
+
+ new_map_sym.value = sym->value;
+ new_map_sym.type = name[1];
+
+ /* Assume that most mapping symbols appear in order of increasing
+ value. If they were randomly distributed, it would be faster to
+ always push here and then sort at first use. */
+ if (!VEC_empty (arm_mapping_symbol_s, *map_p))
+ {
+ struct arm_mapping_symbol *prev_map_sym;
+
+ prev_map_sym = VEC_last (arm_mapping_symbol_s, *map_p);
+ if (prev_map_sym->value >= sym->value)
+ {
+ unsigned int idx;
+ idx = VEC_lower_bound (arm_mapping_symbol_s, *map_p, &new_map_sym,
+ arm_compare_mapping_symbols);
+ VEC_safe_insert (arm_mapping_symbol_s, *map_p, idx, &new_map_sym);
+ return;
+ }
+ }
+
+ VEC_safe_push (arm_mapping_symbol_s, *map_p, &new_map_sym);
+}
+
+static void
+arm_write_pc (struct regcache *regcache, CORE_ADDR pc)
+{
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ regcache_cooked_write_unsigned (regcache, ARM_PC_REGNUM, pc);
+
+ /* If necessary, set the T bit. */
+ if (arm_apcs_32)
+ {
+ ULONGEST val, t_bit;
+ regcache_cooked_read_unsigned (regcache, ARM_PS_REGNUM, &val);
+ t_bit = arm_psr_thumb_bit (gdbarch);
+ if (arm_pc_is_thumb (gdbarch, pc))
+ regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM,
+ val | t_bit);
+ else
+ regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM,
+ val & ~t_bit);
+ }
+}
+
+/* Read the contents of a NEON quad register, by reading from two
+ double registers. This is used to implement the quad pseudo
+ registers, and for argument passing in case the quad registers are
+ missing; vectors are passed in quad registers when using the VFP
+ ABI, even if a NEON unit is not present. REGNUM is the index of
+ the quad register, in [0, 15]. */
-static int
-coff_sym_is_thumb (int val)
+static void
+arm_neon_quad_read (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, gdb_byte *buf)
{
- return (val == C_THUMBEXT ||
- val == C_THUMBSTAT ||
- val == C_THUMBEXTFUNC ||
- val == C_THUMBSTATFUNC ||
- val == C_THUMBLABEL);
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
+
+ sprintf (name_buf, "d%d", regnum << 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ /* d0 is always the least significant half of q0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = 8;
+ else
+ offset = 0;
+
+ regcache_raw_read (regcache, double_regnum, reg_buf);
+ memcpy (buf + offset, reg_buf, 8);
+
+ offset = 8 - offset;
+ regcache_raw_read (regcache, double_regnum + 1, reg_buf);
+ memcpy (buf + offset, reg_buf, 8);
}
-/* arm_coff_make_msymbol_special()
- arm_elf_make_msymbol_special()
-
- These functions test whether the COFF or ELF symbol corresponds to
- an address in thumb code, and set a "special" bit in a minimal
- symbol to indicate that it does. */
-
static void
-arm_elf_make_msymbol_special(asymbol *sym, struct minimal_symbol *msym)
+arm_pseudo_read (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, gdb_byte *buf)
{
- /* Thumb symbols are of type STT_LOPROC, (synonymous with
- STT_ARM_TFUNC). */
- if (ELF_ST_TYPE (((elf_symbol_type *)sym)->internal_elf_sym.st_info)
- == STT_LOPROC)
- MSYMBOL_SET_SPECIAL (msym);
+ const int num_regs = gdbarch_num_regs (gdbarch);
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
+
+ gdb_assert (regnum >= num_regs);
+ regnum -= num_regs;
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos && regnum >= 32 && regnum < 48)
+ /* Quad-precision register. */
+ arm_neon_quad_read (gdbarch, regcache, regnum - 32, buf);
+ else
+ {
+ /* Single-precision register. */
+ gdb_assert (regnum < 32);
+
+ /* s0 is always the least significant half of d0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = (regnum & 1) ? 0 : 4;
+ else
+ offset = (regnum & 1) ? 4 : 0;
+
+ sprintf (name_buf, "d%d", regnum >> 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ regcache_raw_read (regcache, double_regnum, reg_buf);
+ memcpy (buf, reg_buf + offset, 4);
+ }
}
+/* Store the contents of BUF to a NEON quad register, by writing to
+ two double registers. This is used to implement the quad pseudo
+ registers, and for argument passing in case the quad registers are
+ missing; vectors are passed in quad registers when using the VFP
+ ABI, even if a NEON unit is not present. REGNUM is the index
+ of the quad register, in [0, 15]. */
+
static void
-arm_coff_make_msymbol_special(int val, struct minimal_symbol *msym)
+arm_neon_quad_write (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, const gdb_byte *buf)
{
- if (coff_sym_is_thumb (val))
- MSYMBOL_SET_SPECIAL (msym);
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
+
+ sprintf (name_buf, "d%d", regnum << 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ /* d0 is always the least significant half of q0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = 8;
+ else
+ offset = 0;
+
+ regcache_raw_write (regcache, double_regnum, buf + offset);
+ offset = 8 - offset;
+ regcache_raw_write (regcache, double_regnum + 1, buf + offset);
}
static void
-arm_write_pc (struct regcache *regcache, CORE_ADDR pc)
+arm_pseudo_write (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, const gdb_byte *buf)
{
- regcache_cooked_write_unsigned (regcache, ARM_PC_REGNUM, pc);
+ const int num_regs = gdbarch_num_regs (gdbarch);
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
- /* If necessary, set the T bit. */
- if (arm_apcs_32)
+ gdb_assert (regnum >= num_regs);
+ regnum -= num_regs;
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos && regnum >= 32 && regnum < 48)
+ /* Quad-precision register. */
+ arm_neon_quad_write (gdbarch, regcache, regnum - 32, buf);
+ else
{
- ULONGEST val;
- regcache_cooked_read_unsigned (regcache, ARM_PS_REGNUM, &val);
- if (arm_pc_is_thumb (pc))
- regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM, val | 0x20);
+ /* Single-precision register. */
+ gdb_assert (regnum < 32);
+
+ /* s0 is always the least significant half of d0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = (regnum & 1) ? 0 : 4;
else
- regcache_cooked_write_unsigned (regcache, ARM_PS_REGNUM,
- val & ~(ULONGEST) 0x20);
+ offset = (regnum & 1) ? 4 : 0;
+
+ sprintf (name_buf, "d%d", regnum >> 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ regcache_raw_read (regcache, double_regnum, reg_buf);
+ memcpy (reg_buf + offset, buf, 4);
+ regcache_raw_write (regcache, double_regnum, reg_buf);
}
}
return osabi;
}
+static int
+arm_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
+ struct reggroup *group)
+{
+ /* FPS register's type is INT, but belongs to float_reggroup. Beside
+ this, FPS register belongs to save_regroup, restore_reggroup, and
+ all_reggroup, of course. */
+ if (regnum == ARM_FPS_REGNUM)
+ return (group == float_reggroup
+ || group == save_reggroup
+ || group == restore_reggroup
+ || group == all_reggroup);
+ else
+ return default_register_reggroup_p (gdbarch, regnum, group);
+}
+
\f
/* Initialize the current architecture based on INFO. If possible,
re-use an architecture from ARCHES, which is a list of
enum arm_abi_kind arm_abi = arm_abi_global;
enum arm_float_model fp_model = arm_fp_model;
struct tdesc_arch_data *tdesc_data = NULL;
- int i;
+ int i, is_m = 0;
+ int have_vfp_registers = 0, have_vfp_pseudos = 0, have_neon_pseudos = 0;
+ int have_neon = 0;
int have_fpa_registers = 1;
+ const struct target_desc *tdesc = info.target_desc;
+
+ /* If we have an object to base this architecture on, try to determine
+ its ABI. */
+
+ if (arm_abi == ARM_ABI_AUTO && info.abfd != NULL)
+ {
+ int ei_osabi, e_flags;
+
+ switch (bfd_get_flavour (info.abfd))
+ {
+ case bfd_target_aout_flavour:
+ /* Assume it's an old APCS-style ABI. */
+ arm_abi = ARM_ABI_APCS;
+ break;
+
+ case bfd_target_coff_flavour:
+ /* Assume it's an old APCS-style ABI. */
+ /* XXX WinCE? */
+ arm_abi = ARM_ABI_APCS;
+ break;
+
+ case bfd_target_elf_flavour:
+ ei_osabi = elf_elfheader (info.abfd)->e_ident[EI_OSABI];
+ e_flags = elf_elfheader (info.abfd)->e_flags;
+
+ if (ei_osabi == ELFOSABI_ARM)
+ {
+ /* GNU tools used to use this value, but do not for EABI
+ objects. There's nowhere to tag an EABI version
+ anyway, so assume APCS. */
+ arm_abi = ARM_ABI_APCS;
+ }
+ else if (ei_osabi == ELFOSABI_NONE)
+ {
+ int eabi_ver = EF_ARM_EABI_VERSION (e_flags);
+ int attr_arch, attr_profile;
+
+ switch (eabi_ver)
+ {
+ case EF_ARM_EABI_UNKNOWN:
+ /* Assume GNU tools. */
+ arm_abi = ARM_ABI_APCS;
+ break;
+
+ case EF_ARM_EABI_VER4:
+ case EF_ARM_EABI_VER5:
+ arm_abi = ARM_ABI_AAPCS;
+ /* EABI binaries default to VFP float ordering.
+ They may also contain build attributes that can
+ be used to identify if the VFP argument-passing
+ ABI is in use. */
+ if (fp_model == ARM_FLOAT_AUTO)
+ {
+#ifdef HAVE_ELF
+ switch (bfd_elf_get_obj_attr_int (info.abfd,
+ OBJ_ATTR_PROC,
+ Tag_ABI_VFP_args))
+ {
+ case 0:
+ /* "The user intended FP parameter/result
+ passing to conform to AAPCS, base
+ variant". */
+ fp_model = ARM_FLOAT_SOFT_VFP;
+ break;
+ case 1:
+ /* "The user intended FP parameter/result
+ passing to conform to AAPCS, VFP
+ variant". */
+ fp_model = ARM_FLOAT_VFP;
+ break;
+ case 2:
+ /* "The user intended FP parameter/result
+ passing to conform to tool chain-specific
+ conventions" - we don't know any such
+ conventions, so leave it as "auto". */
+ break;
+ default:
+ /* Attribute value not mentioned in the
+ October 2008 ABI, so leave it as
+ "auto". */
+ break;
+ }
+#else
+ fp_model = ARM_FLOAT_SOFT_VFP;
+#endif
+ }
+ break;
+
+ default:
+ /* Leave it as "auto". */
+ warning (_("unknown ARM EABI version 0x%x"), eabi_ver);
+ break;
+ }
+
+#ifdef HAVE_ELF
+ /* Detect M-profile programs. This only works if the
+ executable file includes build attributes; GCC does
+ copy them to the executable, but e.g. RealView does
+ not. */
+ attr_arch = bfd_elf_get_obj_attr_int (info.abfd, OBJ_ATTR_PROC,
+ Tag_CPU_arch);
+ attr_profile = bfd_elf_get_obj_attr_int (info.abfd,
+ OBJ_ATTR_PROC,
+ Tag_CPU_arch_profile);
+ /* GCC specifies the profile for v6-M; RealView only
+ specifies the profile for architectures starting with
+ V7 (as opposed to architectures with a tag
+ numerically greater than TAG_CPU_ARCH_V7). */
+ if (!tdesc_has_registers (tdesc)
+ && (attr_arch == TAG_CPU_ARCH_V6_M
+ || attr_arch == TAG_CPU_ARCH_V6S_M
+ || attr_profile == 'M'))
+ tdesc = tdesc_arm_with_m;
+#endif
+ }
+
+ if (fp_model == ARM_FLOAT_AUTO)
+ {
+ int e_flags = elf_elfheader (info.abfd)->e_flags;
+
+ switch (e_flags & (EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT))
+ {
+ case 0:
+ /* Leave it as "auto". Strictly speaking this case
+ means FPA, but almost nobody uses that now, and
+ many toolchains fail to set the appropriate bits
+ for the floating-point model they use. */
+ break;
+ case EF_ARM_SOFT_FLOAT:
+ fp_model = ARM_FLOAT_SOFT_FPA;
+ break;
+ case EF_ARM_VFP_FLOAT:
+ fp_model = ARM_FLOAT_VFP;
+ break;
+ case EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT:
+ fp_model = ARM_FLOAT_SOFT_VFP;
+ break;
+ }
+ }
+
+ if (e_flags & EF_ARM_BE8)
+ info.byte_order_for_code = BFD_ENDIAN_LITTLE;
+
+ break;
+
+ default:
+ /* Leave it as "auto". */
+ break;
+ }
+ }
/* Check any target description for validity. */
- if (tdesc_has_registers (info.target_desc))
+ if (tdesc_has_registers (tdesc))
{
/* For most registers we require GDB's default names; but also allow
the numeric names for sp / lr / pc, as a convenience. */
static const char *const arm_pc_names[] = { "r15", "pc", NULL };
const struct tdesc_feature *feature;
- int i, valid_p;
+ int valid_p;
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.arm.core");
if (feature == NULL)
- return NULL;
+ {
+ feature = tdesc_find_feature (tdesc,
+ "org.gnu.gdb.arm.m-profile");
+ if (feature == NULL)
+ return NULL;
+ else
+ is_m = 1;
+ }
tdesc_data = tdesc_data_alloc ();
valid_p &= tdesc_numbered_register_choices (feature, tdesc_data,
ARM_PC_REGNUM,
arm_pc_names);
- valid_p &= tdesc_numbered_register (feature, tdesc_data,
- ARM_PS_REGNUM, "cpsr");
+ if (is_m)
+ valid_p &= tdesc_numbered_register (feature, tdesc_data,
+ ARM_PS_REGNUM, "xpsr");
+ else
+ valid_p &= tdesc_numbered_register (feature, tdesc_data,
+ ARM_PS_REGNUM, "cpsr");
if (!valid_p)
{
return NULL;
}
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.arm.fpa");
if (feature != NULL)
{
else
have_fpa_registers = 0;
- feature = tdesc_find_feature (info.target_desc,
+ feature = tdesc_find_feature (tdesc,
"org.gnu.gdb.xscale.iwmmxt");
if (feature != NULL)
{
return NULL;
}
}
- }
-
- /* If we have an object to base this architecture on, try to determine
- its ABI. */
-
- if (arm_abi == ARM_ABI_AUTO && info.abfd != NULL)
- {
- int ei_osabi, e_flags;
- switch (bfd_get_flavour (info.abfd))
+ /* If we have a VFP unit, check whether the single precision registers
+ are present. If not, then we will synthesize them as pseudo
+ registers. */
+ feature = tdesc_find_feature (tdesc,
+ "org.gnu.gdb.arm.vfp");
+ if (feature != NULL)
{
- case bfd_target_aout_flavour:
- /* Assume it's an old APCS-style ABI. */
- arm_abi = ARM_ABI_APCS;
- break;
-
- case bfd_target_coff_flavour:
- /* Assume it's an old APCS-style ABI. */
- /* XXX WinCE? */
- arm_abi = ARM_ABI_APCS;
- break;
-
- case bfd_target_elf_flavour:
- ei_osabi = elf_elfheader (info.abfd)->e_ident[EI_OSABI];
- e_flags = elf_elfheader (info.abfd)->e_flags;
+ static const char *const vfp_double_names[] = {
+ "d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7",
+ "d8", "d9", "d10", "d11", "d12", "d13", "d14", "d15",
+ "d16", "d17", "d18", "d19", "d20", "d21", "d22", "d23",
+ "d24", "d25", "d26", "d27", "d28", "d29", "d30", "d31",
+ };
- if (ei_osabi == ELFOSABI_ARM)
+ /* Require the double precision registers. There must be either
+ 16 or 32. */
+ valid_p = 1;
+ for (i = 0; i < 32; i++)
{
- /* GNU tools used to use this value, but do not for EABI
- objects. There's nowhere to tag an EABI version
- anyway, so assume APCS. */
- arm_abi = ARM_ABI_APCS;
+ valid_p &= tdesc_numbered_register (feature, tdesc_data,
+ ARM_D0_REGNUM + i,
+ vfp_double_names[i]);
+ if (!valid_p)
+ break;
}
- else if (ei_osabi == ELFOSABI_NONE)
- {
- int eabi_ver = EF_ARM_EABI_VERSION (e_flags);
- switch (eabi_ver)
- {
- case EF_ARM_EABI_UNKNOWN:
- /* Assume GNU tools. */
- arm_abi = ARM_ABI_APCS;
- break;
+ if (!valid_p && i != 16)
+ {
+ tdesc_data_cleanup (tdesc_data);
+ return NULL;
+ }
- case EF_ARM_EABI_VER4:
- case EF_ARM_EABI_VER5:
- arm_abi = ARM_ABI_AAPCS;
- /* EABI binaries default to VFP float ordering. */
- if (fp_model == ARM_FLOAT_AUTO)
- fp_model = ARM_FLOAT_SOFT_VFP;
- break;
+ if (tdesc_unnumbered_register (feature, "s0") == 0)
+ have_vfp_pseudos = 1;
- default:
- /* Leave it as "auto". */
- warning (_("unknown ARM EABI version 0x%x"), eabi_ver);
- break;
- }
- }
+ have_vfp_registers = 1;
- if (fp_model == ARM_FLOAT_AUTO)
+ /* If we have VFP, also check for NEON. The architecture allows
+ NEON without VFP (integer vector operations only), but GDB
+ does not support that. */
+ feature = tdesc_find_feature (tdesc,
+ "org.gnu.gdb.arm.neon");
+ if (feature != NULL)
{
- int e_flags = elf_elfheader (info.abfd)->e_flags;
-
- switch (e_flags & (EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT))
+ /* NEON requires 32 double-precision registers. */
+ if (i != 32)
{
- case 0:
- /* Leave it as "auto". Strictly speaking this case
- means FPA, but almost nobody uses that now, and
- many toolchains fail to set the appropriate bits
- for the floating-point model they use. */
- break;
- case EF_ARM_SOFT_FLOAT:
- fp_model = ARM_FLOAT_SOFT_FPA;
- break;
- case EF_ARM_VFP_FLOAT:
- fp_model = ARM_FLOAT_VFP;
- break;
- case EF_ARM_SOFT_FLOAT | EF_ARM_VFP_FLOAT:
- fp_model = ARM_FLOAT_SOFT_VFP;
- break;
+ tdesc_data_cleanup (tdesc_data);
+ return NULL;
}
- }
- break;
- default:
- /* Leave it as "auto". */
- break;
+ /* If there are quad registers defined by the stub, use
+ their type; otherwise (normally) provide them with
+ the default type. */
+ if (tdesc_unnumbered_register (feature, "q0") == 0)
+ have_neon_pseudos = 1;
+
+ have_neon = 1;
+ }
}
}
&& fp_model != gdbarch_tdep (best_arch->gdbarch)->fp_model)
continue;
+ /* There are various other properties in tdep that we do not
+ need to check here: those derived from a target description,
+ since gdbarches with a different target description are
+ automatically disqualified. */
+
+ /* Do check is_m, though, since it might come from the binary. */
+ if (is_m != gdbarch_tdep (best_arch->gdbarch)->is_m)
+ continue;
+
/* Found a match. */
break;
}
These are gdbarch discriminators, like the OSABI. */
tdep->arm_abi = arm_abi;
tdep->fp_model = fp_model;
+ tdep->is_m = is_m;
tdep->have_fpa_registers = have_fpa_registers;
+ tdep->have_vfp_registers = have_vfp_registers;
+ tdep->have_vfp_pseudos = have_vfp_pseudos;
+ tdep->have_neon_pseudos = have_neon_pseudos;
+ tdep->have_neon = have_neon;
/* Breakpoints. */
- switch (info.byte_order)
+ switch (info.byte_order_for_code)
{
case BFD_ENDIAN_BIG:
tdep->arm_breakpoint = arm_default_arm_be_breakpoint;
/* On ARM targets char defaults to unsigned. */
set_gdbarch_char_signed (gdbarch, 0);
+ /* Note: for displaced stepping, this includes the breakpoint, and one word
+ of additional scratch space. This setting isn't used for anything beside
+ displaced stepping at present. */
+ set_gdbarch_max_insn_length (gdbarch, 4 * DISPLACED_MODIFIED_INSNS);
+
/* This should be low enough for everything. */
tdep->lowest_pc = 0x20;
tdep->jb_pc = -1; /* Longjump support not enabled by default. */
/* Advance PC across function entry code. */
set_gdbarch_skip_prologue (gdbarch, arm_skip_prologue);
+ /* Detect whether PC is in function epilogue. */
+ set_gdbarch_in_function_epilogue_p (gdbarch, arm_in_function_epilogue_p);
+
/* Skip trampolines. */
set_gdbarch_skip_trampoline_code (gdbarch, arm_skip_stub);
/* Breakpoint manipulation. */
set_gdbarch_breakpoint_from_pc (gdbarch, arm_breakpoint_from_pc);
+ set_gdbarch_remote_breakpoint_from_pc (gdbarch,
+ arm_remote_breakpoint_from_pc);
/* Information about registers, etc. */
- set_gdbarch_deprecated_fp_regnum (gdbarch, ARM_FP_REGNUM); /* ??? */
set_gdbarch_sp_regnum (gdbarch, ARM_SP_REGNUM);
set_gdbarch_pc_regnum (gdbarch, ARM_PC_REGNUM);
set_gdbarch_num_regs (gdbarch, ARM_NUM_REGS);
set_gdbarch_register_type (gdbarch, arm_register_type);
+ set_gdbarch_register_reggroup_p (gdbarch, arm_register_reggroup_p);
/* This "info float" is FPA-specific. Use the generic version if we
do not have FPA. */
set_gdbarch_print_float_info (gdbarch, arm_print_float_info);
/* Internal <-> external register number maps. */
- set_gdbarch_dwarf_reg_to_regnum (gdbarch, arm_dwarf_reg_to_regnum);
set_gdbarch_dwarf2_reg_to_regnum (gdbarch, arm_dwarf_reg_to_regnum);
set_gdbarch_register_sim_regno (gdbarch, arm_register_sim_regno);
set_gdbarch_elf_make_msymbol_special (gdbarch, arm_elf_make_msymbol_special);
set_gdbarch_coff_make_msymbol_special (gdbarch,
arm_coff_make_msymbol_special);
+ set_gdbarch_record_special_symbol (gdbarch, arm_record_special_symbol);
+
+ /* Thumb-2 IT block support. */
+ set_gdbarch_adjust_breakpoint_address (gdbarch,
+ arm_adjust_breakpoint_address);
/* Virtual tables. */
set_gdbarch_vbit_in_delta (gdbarch, 1);
/* Hook in the ABI-specific overrides, if they have been registered. */
gdbarch_init_osabi (info, gdbarch);
+ dwarf2_frame_set_init_reg (gdbarch, arm_dwarf2_frame_init_reg);
+
/* Add some default predicates. */
frame_unwind_append_unwinder (gdbarch, &arm_stub_unwind);
dwarf2_append_unwinders (gdbarch);
+ frame_unwind_append_unwinder (gdbarch, &arm_exidx_unwind);
frame_unwind_append_unwinder (gdbarch, &arm_prologue_unwind);
/* Now we have tuned the configuration, set a few final things,
if (tdep->arm_abi == ARM_ABI_AUTO)
tdep->arm_abi = ARM_ABI_APCS;
+ /* Watchpoints are not steppable. */
+ set_gdbarch_have_nonsteppable_watchpoint (gdbarch, 1);
+
/* We used to default to FPA for generic ARM, but almost nobody
uses that now, and we now provide a way for the user to force
the model. So default to the most useful variant. */
set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double);
}
+ if (have_vfp_pseudos)
+ {
+ /* NOTE: These are the only pseudo registers used by
+ the ARM target at the moment. If more are added, a
+ little more care in numbering will be needed. */
+
+ int num_pseudos = 32;
+ if (have_neon_pseudos)
+ num_pseudos += 16;
+ set_gdbarch_num_pseudo_regs (gdbarch, num_pseudos);
+ set_gdbarch_pseudo_register_read (gdbarch, arm_pseudo_read);
+ set_gdbarch_pseudo_register_write (gdbarch, arm_pseudo_write);
+ }
+
if (tdesc_data)
- tdesc_use_registers (gdbarch, info.target_desc, tdesc_data);
+ {
+ set_tdesc_pseudo_register_name (gdbarch, arm_register_name);
+
+ tdesc_use_registers (gdbarch, tdesc, tdesc_data);
+
+ /* Override tdesc_register_type to adjust the types of VFP
+ registers for NEON. */
+ set_gdbarch_register_type (gdbarch, arm_register_type);
+ }
/* Add standard register aliases. We add aliases even for those
nanes which are used by the current architecture - it's simpler,
gdbarch_register (bfd_arch_arm, arm_gdbarch_init, arm_dump_tdep);
+ arm_objfile_data_key
+ = register_objfile_data_with_cleanup (NULL, arm_objfile_data_free);
+
+ /* Add ourselves to objfile event chain. */
+ observer_attach_new_objfile (arm_exidx_new_objfile);
+ arm_exidx_data_key
+ = register_objfile_data_with_cleanup (NULL, arm_exidx_data_free);
+
/* Register an ELF OS ABI sniffer for ARM binaries. */
gdbarch_register_osabi_sniffer (bfd_arch_arm,
bfd_target_elf_flavour,
arm_elf_osabi_sniffer);
+ /* Initialize the standard target descriptions. */
+ initialize_tdesc_arm_with_m ();
+
/* Get the number of possible sets of register names defined in opcodes. */
num_disassembly_options = get_arm_regname_num_options ();
_("The valid values are:\n"),
regdesc,
_("The default is \"std\"."));
- helptext = ui_file_xstrdup (stb, &length);
+ helptext = ui_file_xstrdup (stb, NULL);
ui_file_delete (stb);
add_setshow_enum_cmd("disassembler", no_class,
_("Show the disassembly style."),
helptext,
set_disassembly_style_sfunc,
- NULL, /* FIXME: i18n: The disassembly style is \"%s\". */
+ NULL, /* FIXME: i18n: The disassembly style is
+ \"%s\". */
&setarmcmdlist, &showarmcmdlist);
add_setshow_boolean_cmd ("apcs32", no_class, &arm_apcs_32,
_("Show usage of ARM 32-bit mode."),
_("When off, a 26-bit PC will be used."),
NULL,
- NULL, /* FIXME: i18n: Usage of ARM 32-bit mode is %s. */
+ NULL, /* FIXME: i18n: Usage of ARM 32-bit
+ mode is %s. */
&setarmcmdlist, &showarmcmdlist);
/* Add a command to allow the user to force the FPU model. */
NULL, arm_set_abi, arm_show_abi,
&setarmcmdlist, &showarmcmdlist);
+ /* Add two commands to allow the user to force the assumed
+ execution mode. */
+ add_setshow_enum_cmd ("fallback-mode", class_support,
+ arm_mode_strings, &arm_fallback_mode_string,
+ _("Set the mode assumed when symbols are unavailable."),
+ _("Show the mode assumed when symbols are unavailable."),
+ NULL, NULL, arm_show_fallback_mode,
+ &setarmcmdlist, &showarmcmdlist);
+ add_setshow_enum_cmd ("force-mode", class_support,
+ arm_mode_strings, &arm_force_mode_string,
+ _("Set the mode assumed even when symbols are available."),
+ _("Show the mode assumed even when symbols are available."),
+ NULL, NULL, arm_show_force_mode,
+ &setarmcmdlist, &showarmcmdlist);
+
/* Debugging flag. */
add_setshow_boolean_cmd ("arm", class_maintenance, &arm_debug,
_("Set ARM debugging."),