/* Motorola m68k target-dependent support for GNU/Linux.
- Copyright 1996, 1998, 2000, 2001, 2002, 2003 Free Software Foundation,
- Inc.
+ Copyright 1996, 1998, 2000, 2001, 2002, 2003, 2004
+ Free Software Foundation, Inc.
This file is part of GDB.
#include "defs.h"
#include "gdbcore.h"
+#include "doublest.h"
+#include "floatformat.h"
#include "frame.h"
#include "target.h"
#include "gdb_string.h"
#include "gdbtypes.h"
+#include "osabi.h"
+#include "regcache.h"
+#include "objfiles.h"
+#include "symtab.h"
#include "m68k-tdep.h"
+#include "trad-frame.h"
+#include "frame-unwind.h"
\f
+/* Offsets (in target ints) into jmp_buf. */
+
+#define M68K_LINUX_JB_ELEMENT_SIZE 4
+#define M68K_LINUX_JB_PC 7
+
/* Check whether insn1 and insn2 are parts of a signal trampoline. */
#define IS_SIGTRAMP(insn1, insn2) \
/* moveq #82,d0; notb d0; trap #0 */ \
|| (insn1 == 0x70524600 && (insn2 >> 16) == 0x4e40))
-/* Return non-zero if PC points into the signal trampoline. For the sake
- of m68k_linux_frame_saved_pc we also distinguish between non-RT and RT
- signal trampolines. */
+/* Return non-zero if PC points into the signal trampoline. For the
+ sake of m68k_linux_get_sigtramp_info we also distinguish between
+ non-RT and RT signal trampolines. */
-int
-m68k_linux_in_sigtramp (CORE_ADDR pc)
+static int
+m68k_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
{
CORE_ADDR sp;
char buf[12];
if (IS_RT_SIGTRAMP (insn0, insn1))
return 2;
- insn0 = (insn0 << 16) | (insn1 >> 16);
- insn1 = (insn1 << 16) | (insn2 >> 16);
+ insn0 = ((insn0 << 16) & 0xffffffff) | (insn1 >> 16);
+ insn1 = ((insn1 << 16) & 0xffffffff) | (insn2 >> 16);
if (IS_SIGTRAMP (insn0, insn1))
return 1;
if (IS_RT_SIGTRAMP (insn0, insn1))
return 0;
}
-/* Offset to saved PC in sigcontext, from <asm/sigcontext.h>. */
-#define SIGCONTEXT_PC_OFFSET 26
+/* From <asm/sigcontext.h>. */
+static int m68k_linux_sigcontext_reg_offset[M68K_NUM_REGS] =
+{
+ 2 * 4, /* %d0 */
+ 3 * 4, /* %d1 */
+ -1, /* %d2 */
+ -1, /* %d3 */
+ -1, /* %d4 */
+ -1, /* %d5 */
+ -1, /* %d6 */
+ -1, /* %d7 */
+ 4 * 4, /* %a0 */
+ 5 * 4, /* %a1 */
+ -1, /* %a2 */
+ -1, /* %a3 */
+ -1, /* %a4 */
+ -1, /* %a5 */
+ -1, /* %fp */
+ 1 * 4, /* %sp */
+ 5 * 4 + 2, /* %sr */
+ 6 * 4 + 2, /* %pc */
+ 8 * 4, /* %fp0 */
+ 11 * 4, /* %fp1 */
+ -1, /* %fp2 */
+ -1, /* %fp3 */
+ -1, /* %fp4 */
+ -1, /* %fp5 */
+ -1, /* %fp6 */
+ -1, /* %fp7 */
+ 14 * 4, /* %fpcr */
+ 15 * 4, /* %fpsr */
+ 16 * 4 /* %fpiaddr */
+};
+
+/* From <asm/ucontext.h>. */
+static int m68k_linux_ucontext_reg_offset[M68K_NUM_REGS] =
+{
+ 6 * 4, /* %d0 */
+ 7 * 4, /* %d1 */
+ 8 * 4, /* %d2 */
+ 9 * 4, /* %d3 */
+ 10 * 4, /* %d4 */
+ 11 * 4, /* %d5 */
+ 12 * 4, /* %d6 */
+ 13 * 4, /* %d7 */
+ 14 * 4, /* %a0 */
+ 15 * 4, /* %a1 */
+ 16 * 4, /* %a2 */
+ 17 * 4, /* %a3 */
+ 18 * 4, /* %a4 */
+ 19 * 4, /* %a5 */
+ 20 * 4, /* %fp */
+ 21 * 4, /* %sp */
+ 23 * 4, /* %sr */
+ 22 * 4, /* %pc */
+ 27 * 4, /* %fp0 */
+ 30 * 4, /* %fp1 */
+ 33 * 4, /* %fp2 */
+ 36 * 4, /* %fp3 */
+ 39 * 4, /* %fp4 */
+ 42 * 4, /* %fp5 */
+ 45 * 4, /* %fp6 */
+ 48 * 4, /* %fp7 */
+ 24 * 4, /* %fpcr */
+ 25 * 4, /* %fpsr */
+ 26 * 4 /* %fpiaddr */
+};
-/* Offset to saved PC in ucontext, from <asm/ucontext.h>. */
-#define UCONTEXT_PC_OFFSET 88
-/* Get saved user PC for sigtramp from sigcontext or ucontext. */
+/* Get info about saved registers in sigtramp. */
-static CORE_ADDR
-m68k_linux_sigtramp_saved_pc (struct frame_info *frame)
+struct m68k_linux_sigtramp_info
{
+ /* Address of sigcontext. */
CORE_ADDR sigcontext_addr;
- char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
- int ptrbytes = TARGET_PTR_BIT / TARGET_CHAR_BIT;
- int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT;
+
+ /* Offset of registers in `struct sigcontext'. */
+ int *sc_reg_offset;
+};
+
+static struct m68k_linux_sigtramp_info
+m68k_linux_get_sigtramp_info (struct frame_info *next_frame)
+{
+ CORE_ADDR sp;
+ char buf[4];
+ struct m68k_linux_sigtramp_info info;
+
+ frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
+ sp = extract_unsigned_integer (buf, 4);
/* Get sigcontext address, it is the third parameter on the stack. */
- if (get_next_frame (frame))
- sigcontext_addr
- = read_memory_unsigned_integer (get_frame_base (get_next_frame (frame))
- + FRAME_ARGS_SKIP
- + sigcontext_offs,
- ptrbytes);
- else
- sigcontext_addr
- = read_memory_unsigned_integer (read_register (SP_REGNUM)
- + sigcontext_offs,
- ptrbytes);
-
- /* Don't cause a memory_error when accessing sigcontext in case the
- stack layout has changed or the stack is corrupt. */
- if (m68k_linux_in_sigtramp (get_frame_pc (frame)) == 2)
- target_read_memory (sigcontext_addr + UCONTEXT_PC_OFFSET, buf, ptrbytes);
+ info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4);
+
+ if (m68k_linux_pc_in_sigtramp (frame_pc_unwind (next_frame), 0) == 2)
+ info.sc_reg_offset = m68k_linux_ucontext_reg_offset;
else
- target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes);
- return extract_unsigned_integer (buf, ptrbytes);
+ info.sc_reg_offset = m68k_linux_sigcontext_reg_offset;
+ return info;
}
-/* Return the saved program counter for FRAME. */
+/* Signal trampolines. */
-CORE_ADDR
-m68k_linux_frame_saved_pc (struct frame_info *frame)
+static struct trad_frame_cache *
+m68k_linux_sigtramp_frame_cache (struct frame_info *next_frame,
+ void **this_cache)
{
- if (get_frame_type (frame) == SIGTRAMP_FRAME)
- return m68k_linux_sigtramp_saved_pc (frame);
+ struct frame_id this_id;
+ struct trad_frame_cache *cache;
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct m68k_linux_sigtramp_info info;
+ char buf[4];
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = trad_frame_cache_zalloc (next_frame);
- return read_memory_unsigned_integer (get_frame_base (frame) + 4, 4);
+ /* FIXME: cagney/2004-05-01: This is is long standing broken code.
+ The frame ID's code address should be the start-address of the
+ signal trampoline and not the current PC within that
+ trampoline. */
+ frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
+ /* See the end of m68k_push_dummy_call. */
+ this_id = frame_id_build (extract_unsigned_integer (buf, 4) - 4 + 8,
+ frame_pc_unwind (next_frame));
+ trad_frame_set_id (cache, this_id);
+
+ info = m68k_linux_get_sigtramp_info (next_frame);
+
+ for (i = 0; i < M68K_NUM_REGS; i++)
+ if (info.sc_reg_offset[i] != -1)
+ trad_frame_set_reg_addr (cache, i,
+ info.sigcontext_addr + info.sc_reg_offset[i]);
+
+ *this_cache = cache;
+ return cache;
}
-void
-m68k_linux_extract_return_value (struct type *type, char *regbuf, char *valbuf)
+static void
+m68k_linux_sigtramp_frame_this_id (struct frame_info *next_frame,
+ void **this_cache,
+ struct frame_id *this_id)
{
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
- {
- REGISTER_CONVERT_TO_VIRTUAL (FP0_REGNUM, type,
- regbuf + REGISTER_BYTE (FP0_REGNUM),
- valbuf);
- }
- else if (TYPE_CODE (type) == TYPE_CODE_PTR)
- memcpy (valbuf, regbuf + REGISTER_BYTE (M68K_A0_REGNUM),
- TYPE_LENGTH (type));
- else
- memcpy (valbuf,
- regbuf + (TYPE_LENGTH (type) >= 4 ? 0 : 4 - TYPE_LENGTH (type)),
- TYPE_LENGTH (type));
+ struct trad_frame_cache *cache =
+ m68k_linux_sigtramp_frame_cache (next_frame, this_cache);
+ trad_frame_get_id (cache, this_id);
}
-void
-m68k_linux_store_return_value (struct type *type, char *valbuf)
+static void
+m68k_linux_sigtramp_frame_prev_register (struct frame_info *next_frame,
+ void **this_cache,
+ int regnum, int *optimizedp,
+ enum lval_type *lvalp,
+ CORE_ADDR *addrp,
+ int *realnump, void *valuep)
{
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
- {
- char raw_buffer[REGISTER_RAW_SIZE (FP0_REGNUM)];
- REGISTER_CONVERT_TO_RAW (type, FP0_REGNUM, valbuf, raw_buffer);
- deprecated_write_register_bytes (REGISTER_BYTE (FP0_REGNUM),
- raw_buffer, TYPE_LENGTH (type));
- }
- else
- {
- if (TYPE_CODE (type) == TYPE_CODE_PTR)
- deprecated_write_register_bytes (REGISTER_BYTE (M68K_A0_REGNUM),
- valbuf, TYPE_LENGTH (type));
- deprecated_write_register_bytes (0, valbuf, TYPE_LENGTH (type));
- }
+ /* Make sure we've initialized the cache. */
+ struct trad_frame_cache *cache =
+ m68k_linux_sigtramp_frame_cache (next_frame, this_cache);
+ trad_frame_get_register (cache, next_frame, regnum, optimizedp, lvalp,
+ addrp, realnump, valuep);
+}
+
+static const struct frame_unwind m68k_linux_sigtramp_frame_unwind =
+{
+ SIGTRAMP_FRAME,
+ m68k_linux_sigtramp_frame_this_id,
+ m68k_linux_sigtramp_frame_prev_register
+};
+
+static const struct frame_unwind *
+m68k_linux_sigtramp_frame_sniffer (struct frame_info *next_frame)
+{
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
+ char *name;
+
+ find_pc_partial_function (pc, &name, NULL, NULL);
+ if (m68k_linux_pc_in_sigtramp (pc, name))
+ return &m68k_linux_sigtramp_frame_unwind;
+
+ return NULL;
}
-CORE_ADDR
-m68k_linux_extract_struct_value_address (char *regbuf)
+static void
+m68k_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ tdep->jb_pc = M68K_LINUX_JB_PC;
+ tdep->jb_elt_size = M68K_LINUX_JB_ELEMENT_SIZE;
+
+ /* GNU/Linux uses a calling convention that's similar to SVR4. It
+ returns integer values in %d0/%di, pointer values in %a0 and
+ floating values in %fp0, just like SVR4, but uses %a1 to pass the
+ address to store a structure value. It also returns small
+ structures in registers instead of memory. */
+ m68k_svr4_init_abi (info, gdbarch);
+ tdep->struct_value_regnum = M68K_A1_REGNUM;
+ tdep->struct_return = reg_struct_return;
+
+ frame_unwind_append_sniffer (gdbarch, m68k_linux_sigtramp_frame_sniffer);
+
+ /* Shared library handling. */
+ set_gdbarch_in_solib_call_trampoline (gdbarch, in_plt_section);
+ set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
+}
+
+void
+_initialize_m68k_linux_tdep (void)
{
- return *(CORE_ADDR *) (regbuf + REGISTER_BYTE (M68K_A0_REGNUM));
+ gdbarch_register_osabi (bfd_arch_m68k, 0, GDB_OSABI_LINUX,
+ m68k_linux_init_abi);
}