-/* Target-dependent code for the Mitsubishi m32r for GDB, the GNU debugger.
- Copyright 1996, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
+/* Target-dependent code for Renesas M32R, for GDB.
+
+ Copyright (C) 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 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, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
#include "defs.h"
#include "frame.h"
-#include "inferior.h"
-#include "target.h"
-#include "value.h"
-#include "bfd.h"
-#include "gdb_string.h"
+#include "frame-unwind.h"
+#include "frame-base.h"
+#include "symtab.h"
+#include "gdbtypes.h"
+#include "gdbcmd.h"
#include "gdbcore.h"
+#include "gdb_string.h"
+#include "value.h"
+#include "inferior.h"
#include "symfile.h"
+#include "objfiles.h"
+#include "osabi.h"
+#include "language.h"
+#include "arch-utils.h"
#include "regcache.h"
+#include "trad-frame.h"
+#include "dis-asm.h"
+
+#include "gdb_assert.h"
-/* Function: m32r_use_struct_convention
- Return nonzero if call_function should allocate stack space for a
- struct return? */
-int
-m32r_use_struct_convention (int gcc_p, struct type *type)
+#include "m32r-tdep.h"
+
+/* Local functions */
+
+extern void _initialize_m32r_tdep (void);
+
+static CORE_ADDR
+m32r_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
{
- return (TYPE_LENGTH (type) > 8);
+ /* Align to the size of an instruction (so that they can safely be
+ pushed onto the stack. */
+ return sp & ~3;
}
-/* Function: frame_find_saved_regs
- Return the frame_saved_regs structure for the frame.
- Doesn't really work for dummy frames, but it does pass back
- an empty frame_saved_regs, so I guess that's better than total failure */
-void
-m32r_frame_find_saved_regs (struct frame_info *fi,
- struct frame_saved_regs *regaddr)
+/* Breakpoints
+
+ The little endian mode of M32R is unique. In most of architectures,
+ two 16-bit instructions, A and B, are placed as the following:
+
+ Big endian:
+ A0 A1 B0 B1
+
+ Little endian:
+ A1 A0 B1 B0
+
+ In M32R, they are placed like this:
+
+ Big endian:
+ A0 A1 B0 B1
+
+ Little endian:
+ B1 B0 A1 A0
+
+ This is because M32R always fetches instructions in 32-bit.
+
+ The following functions take care of this behavior. */
+
+static int
+m32r_memory_insert_breakpoint (CORE_ADDR addr, bfd_byte *contents_cache)
{
- memcpy (regaddr, &fi->fsr, sizeof (struct frame_saved_regs));
+ int val;
+ gdb_byte buf[4];
+ gdb_byte bp_entry[] = { 0x10, 0xf1 }; /* dpt */
+
+ /* Save the memory contents. */
+ val = target_read_memory (addr & 0xfffffffc, contents_cache, 4);
+ if (val != 0)
+ return val; /* return error */
+
+ /* Determine appropriate breakpoint contents and size for this address. */
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+ {
+ if ((addr & 3) == 0)
+ {
+ buf[0] = bp_entry[0];
+ buf[1] = bp_entry[1];
+ buf[2] = contents_cache[2] & 0x7f;
+ buf[3] = contents_cache[3];
+ }
+ else
+ {
+ buf[0] = contents_cache[0];
+ buf[1] = contents_cache[1];
+ buf[2] = bp_entry[0];
+ buf[3] = bp_entry[1];
+ }
+ }
+ else /* little-endian */
+ {
+ if ((addr & 3) == 0)
+ {
+ buf[0] = contents_cache[0];
+ buf[1] = contents_cache[1] & 0x7f;
+ buf[2] = bp_entry[1];
+ buf[3] = bp_entry[0];
+ }
+ else
+ {
+ buf[0] = bp_entry[1];
+ buf[1] = bp_entry[0];
+ buf[2] = contents_cache[2];
+ buf[3] = contents_cache[3];
+ }
+ }
+
+ /* Write the breakpoint. */
+ val = target_write_memory (addr & 0xfffffffc, buf, 4);
+ return val;
}
-/* Turn this on if you want to see just how much instruction decoding
- if being done, its quite a lot
- */
-#if 0
-static void
-dump_insn (char *commnt, CORE_ADDR pc, int insn)
+static int
+m32r_memory_remove_breakpoint (CORE_ADDR addr, bfd_byte *contents_cache)
+{
+ int val;
+ gdb_byte buf[4];
+
+ buf[0] = contents_cache[0];
+ buf[1] = contents_cache[1];
+ buf[2] = contents_cache[2];
+ buf[3] = contents_cache[3];
+
+ /* Remove parallel bit. */
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+ {
+ if ((buf[0] & 0x80) == 0 && (buf[2] & 0x80) != 0)
+ buf[2] &= 0x7f;
+ }
+ else /* little-endian */
+ {
+ if ((buf[3] & 0x80) == 0 && (buf[1] & 0x80) != 0)
+ buf[1] &= 0x7f;
+ }
+
+ /* Write contents. */
+ val = target_write_memory (addr & 0xfffffffc, buf, 4);
+ return val;
+}
+
+static const gdb_byte *
+m32r_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
+{
+ static gdb_byte be_bp_entry[] = { 0x10, 0xf1, 0x70, 0x00 }; /* dpt -> nop */
+ static gdb_byte le_bp_entry[] = { 0x00, 0x70, 0xf1, 0x10 }; /* dpt -> nop */
+ gdb_byte *bp;
+
+ /* Determine appropriate breakpoint. */
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+ {
+ if ((*pcptr & 3) == 0)
+ {
+ bp = be_bp_entry;
+ *lenptr = 4;
+ }
+ else
+ {
+ bp = be_bp_entry;
+ *lenptr = 2;
+ }
+ }
+ else
+ {
+ if ((*pcptr & 3) == 0)
+ {
+ bp = le_bp_entry;
+ *lenptr = 4;
+ }
+ else
+ {
+ bp = le_bp_entry + 2;
+ *lenptr = 2;
+ }
+ }
+
+ return bp;
+}
+
+
+char *m32r_register_names[] = {
+ "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
+ "r8", "r9", "r10", "r11", "r12", "fp", "lr", "sp",
+ "psw", "cbr", "spi", "spu", "bpc", "pc", "accl", "acch",
+ "evb"
+};
+
+static const char *
+m32r_register_name (int reg_nr)
{
- printf_filtered (" %s %08x %08x ",
- commnt, (unsigned int) pc, (unsigned int) insn);
- TARGET_PRINT_INSN (pc, &tm_print_insn_info);
- printf_filtered ("\n");
+ if (reg_nr < 0)
+ return NULL;
+ if (reg_nr >= M32R_NUM_REGS)
+ return NULL;
+ return m32r_register_names[reg_nr];
}
-#define insn_debug(args) { printf_filtered args; }
-#else
-#define dump_insn(a,b,c) {}
-#define insn_debug(args) {}
-#endif
-
-#define DEFAULT_SEARCH_LIMIT 44
-
-/* Function: scan_prologue
- This function decodes the target function prologue to determine
- 1) the size of the stack frame, and 2) which registers are saved on it.
- It saves the offsets of saved regs in the frame_saved_regs argument,
- and returns the frame size. */
-
-/*
- The sequence it currently generates is:
-
- if (varargs function) { ddi sp,#n }
- push registers
- if (additional stack <= 256) { addi sp,#-stack }
- else if (additional stack < 65k) { add3 sp,sp,#-stack
-
- } else if (additional stack) {
- seth sp,#(stack & 0xffff0000)
- or3 sp,sp,#(stack & 0x0000ffff)
- sub sp,r4
- }
- if (frame pointer) {
- mv sp,fp
- }
-
- These instructions are scheduled like everything else, so you should stop at
- the first branch instruction.
-
- */
-
-/* This is required by skip prologue and by m32r_init_extra_frame_info.
- The results of decoding a prologue should be cached because this
- thrashing is getting nuts.
- I am thinking of making a container class with two indexes, name and
- address. It may be better to extend the symbol table.
- */
+
+
+/* Return the GDB type object for the "standard" data type
+ of data in register N. */
+
+static struct type *
+m32r_register_type (struct gdbarch *gdbarch, int reg_nr)
+{
+ if (reg_nr == M32R_PC_REGNUM)
+ return builtin_type_void_func_ptr;
+ else if (reg_nr == M32R_SP_REGNUM || reg_nr == M32R_FP_REGNUM)
+ return builtin_type_void_data_ptr;
+ else
+ return builtin_type_int32;
+}
+
+
+/* Write into appropriate registers a function return value
+ of type TYPE, given in virtual format.
+
+ Things always get returned in RET1_REGNUM, RET2_REGNUM. */
static void
-decode_prologue (CORE_ADDR start_pc, CORE_ADDR scan_limit, CORE_ADDR *pl_endptr, /* var parameter */
- unsigned long *framelength, struct frame_info *fi,
- struct frame_saved_regs *fsr)
+m32r_store_return_value (struct type *type, struct regcache *regcache,
+ const void *valbuf)
+{
+ CORE_ADDR regval;
+ int len = TYPE_LENGTH (type);
+
+ regval = extract_unsigned_integer (valbuf, len > 4 ? 4 : len);
+ regcache_cooked_write_unsigned (regcache, RET1_REGNUM, regval);
+
+ if (len > 4)
+ {
+ regval = extract_unsigned_integer ((gdb_byte *) valbuf + 4, len - 4);
+ regcache_cooked_write_unsigned (regcache, RET1_REGNUM + 1, regval);
+ }
+}
+
+/* This is required by skip_prologue. The results of decoding a prologue
+ should be cached because this thrashing is getting nuts. */
+
+static int
+decode_prologue (CORE_ADDR start_pc, CORE_ADDR scan_limit,
+ CORE_ADDR *pl_endptr, unsigned long *framelength)
{
unsigned long framesize;
int insn;
int op1;
- int maybe_one_more = 0;
CORE_ADDR after_prologue = 0;
+ CORE_ADDR after_push = 0;
CORE_ADDR after_stack_adjust = 0;
CORE_ADDR current_pc;
-
+ LONGEST return_value;
framesize = 0;
after_prologue = 0;
- insn_debug (("rd prolog l(%d)\n", scan_limit - current_pc));
for (current_pc = start_pc; current_pc < scan_limit; current_pc += 2)
{
+ /* Check if current pc's location is readable. */
+ if (!safe_read_memory_integer (current_pc, 2, &return_value))
+ return -1;
insn = read_memory_unsigned_integer (current_pc, 2);
- dump_insn ("insn-1", current_pc, insn); /* MTZ */
+
+ if (insn == 0x0000)
+ break;
/* If this is a 32 bit instruction, we dont want to examine its
immediate data as though it were an instruction */
if (current_pc & 0x02)
- { /* Clear the parallel execution bit from 16 bit instruction */
- if (maybe_one_more)
- { /* The last instruction was a branch, usually terminates
- the series, but if this is a parallel instruction,
- it may be a stack framing instruction */
- if (!(insn & 0x8000))
- {
- insn_debug (("Really done"));
- break; /* nope, we are really done */
- }
- }
- insn &= 0x7fff; /* decode this instruction further */
+ {
+ /* decode this instruction further */
+ insn &= 0x7fff;
}
else
{
- if (maybe_one_more)
- break; /* This isnt the one more */
if (insn & 0x8000)
{
- insn_debug (("32 bit insn\n"));
if (current_pc == scan_limit)
scan_limit += 2; /* extend the search */
+
current_pc += 2; /* skip the immediate data */
+
+ /* Check if current pc's location is readable. */
+ if (!safe_read_memory_integer (current_pc, 2, &return_value))
+ return -1;
+
if (insn == 0x8faf) /* add3 sp, sp, xxxx */
/* add 16 bit sign-extended offset */
{
- insn_debug (("stack increment\n"));
- framesize += -((short) read_memory_unsigned_integer (current_pc, 2));
+ framesize +=
+ -((short) read_memory_unsigned_integer (current_pc, 2));
}
else
{
- if (((insn >> 8) == 0xe4) && /* ld24 r4, xxxxxx; sub sp, r4 */
- read_memory_unsigned_integer (current_pc + 2, 2) == 0x0f24)
- { /* subtract 24 bit sign-extended negative-offset */
- dump_insn ("insn-2", current_pc + 2, insn);
+ if (((insn >> 8) == 0xe4) /* ld24 r4, xxxxxx; sub sp, r4 */
+ && safe_read_memory_integer (current_pc + 2, 2,
+ &return_value)
+ && read_memory_unsigned_integer (current_pc + 2,
+ 2) == 0x0f24)
+ /* subtract 24 bit sign-extended negative-offset */
+ {
insn = read_memory_unsigned_integer (current_pc - 2, 4);
- dump_insn ("insn-3(l4)", current_pc - 2, insn);
if (insn & 0x00800000) /* sign extend */
insn |= 0xff000000; /* negative */
else
framesize += insn;
}
}
- after_prologue = current_pc;
+ after_push = current_pc + 2;
continue;
}
}
if ((insn & 0xf0ff) == 0x207f)
{ /* st reg, @-sp */
int regno;
- insn_debug (("push\n"));
-#if 0 /* No, PUSH FP is not an indication that we will use a frame pointer. */
- if (((insn & 0xffff) == 0x2d7f) && fi)
- fi->using_frame_pointer = 1;
-#endif
framesize += 4;
-#if 0
-/* Why should we increase the scan limit, just because we did a push?
- And if there is a reason, surely we would only want to do it if we
- had already reached the scan limit... */
- if (current_pc == scan_limit)
- scan_limit += 2;
-#endif
regno = ((insn >> 8) & 0xf);
- if (fsr) /* save_regs offset */
- fsr->regs[regno] = framesize;
after_prologue = 0;
continue;
}
if ((insn >> 8) == 0x4f) /* addi sp, xx */
/* add 8 bit sign-extended offset */
{
- int stack_adjust = (char) (insn & 0xff);
+ int stack_adjust = (gdb_byte) (insn & 0xff);
/* there are probably two of these stack adjustments:
1) A negative one in the prologue, and
}
if (insn == 0x1d8f)
{ /* mv fp, sp */
- if (fi)
- fi->using_frame_pointer = 1; /* fp is now valid */
- insn_debug (("done fp found\n"));
after_prologue = current_pc + 2;
break; /* end of stack adjustments */
}
- if (insn == 0x7000) /* Nop looks like a branch, continue explicitly */
+
+ /* Nop looks like a branch, continue explicitly */
+ if (insn == 0x7000)
{
- insn_debug (("nop\n"));
after_prologue = current_pc + 2;
continue; /* nop occurs between pushes */
}
+ /* End of prolog if any of these are trap instructions */
+ if ((insn & 0xfff0) == 0x10f0)
+ {
+ after_prologue = current_pc;
+ break;
+ }
/* End of prolog if any of these are branch instructions */
- if ((op1 == 0x7000)
- || (op1 == 0xb000)
- || (op1 == 0xf000))
+ if ((op1 == 0x7000) || (op1 == 0xb000) || (op1 == 0xf000))
{
after_prologue = current_pc;
- insn_debug (("Done: branch\n"));
- maybe_one_more = 1;
continue;
}
/* Some of the branch instructions are mixed with other types */
int subop = insn & 0x0ff0;
if ((subop == 0x0ec0) || (subop == 0x0fc0))
{
- insn_debug (("done: jmp\n"));
after_prologue = current_pc;
- maybe_one_more = 1;
continue; /* jmp , jl */
}
}
}
+ if (framelength)
+ *framelength = framesize;
+
if (current_pc >= scan_limit)
{
if (pl_endptr)
{
-#if 1
if (after_stack_adjust != 0)
/* We did not find a "mv fp,sp", but we DID find
a stack_adjust. Is it safe to use that as the
end of the prologue? I just don't know. */
{
*pl_endptr = after_stack_adjust;
- if (framelength)
- *framelength = framesize;
+ }
+ else if (after_push != 0)
+ /* We did not find a "mv fp,sp", but we DID find
+ a push. Is it safe to use that as the
+ end of the prologue? I just don't know. */
+ {
+ *pl_endptr = after_push;
}
else
-#endif
/* We reached the end of the loop without finding the end
of the prologue. No way to win -- we should report failure.
The way we do that is to return the original start_pc.
GDB will set a breakpoint at the start of the function (etc.) */
*pl_endptr = start_pc;
}
- return;
+ return 0;
}
+
if (after_prologue == 0)
after_prologue = current_pc;
- insn_debug ((" framesize %d, firstline %08x\n", framesize, after_prologue));
- if (framelength)
- *framelength = framesize;
if (pl_endptr)
*pl_endptr = after_prologue;
+
+ return 0;
} /* decode_prologue */
/* Function: skip_prologue
Find end of function prologue */
+#define DEFAULT_SEARCH_LIMIT 128
+
CORE_ADDR
m32r_skip_prologue (CORE_ADDR pc)
{
CORE_ADDR func_addr, func_end;
struct symtab_and_line sal;
+ LONGEST return_value;
/* See what the symbol table says */
if (sal.line != 0 && sal.end <= func_end)
{
-
- insn_debug (("BP after prologue %08x\n", sal.end));
func_end = sal.end;
}
else
the end of the function. In this case, there probably isn't a
prologue. */
{
- insn_debug (("No line info, line(%x) sal_end(%x) funcend(%x)\n",
- sal.line, sal.end, func_end));
func_end = min (func_end, func_addr + DEFAULT_SEARCH_LIMIT);
}
}
else
func_end = pc + DEFAULT_SEARCH_LIMIT;
- decode_prologue (pc, func_end, &sal.end, 0, 0, 0);
- return sal.end;
-}
-
-static unsigned long
-m32r_scan_prologue (struct frame_info *fi, struct frame_saved_regs *fsr)
-{
- struct symtab_and_line sal;
- CORE_ADDR prologue_start, prologue_end, current_pc;
- unsigned long framesize = 0;
- /* this code essentially duplicates skip_prologue,
- but we need the start address below. */
+ /* If pc's location is not readable, just quit. */
+ if (!safe_read_memory_integer (pc, 4, &return_value))
+ return pc;
- if (find_pc_partial_function (fi->pc, NULL, &prologue_start, &prologue_end))
- {
- sal = find_pc_line (prologue_start, 0);
+ /* Find the end of prologue. */
+ if (decode_prologue (pc, func_end, &sal.end, NULL) < 0)
+ return pc;
- if (sal.line == 0) /* no line info, use current PC */
- if (prologue_start == entry_point_address ())
- return 0;
- }
- else
- {
- prologue_start = fi->pc;
- prologue_end = prologue_start + 48; /* We're in the boondocks:
- allow for 16 pushes, an add,
- and "mv fp,sp" */
- }
-#if 0
- prologue_end = min (prologue_end, fi->pc);
-#endif
- insn_debug (("fipc(%08x) start(%08x) end(%08x)\n",
- fi->pc, prologue_start, prologue_end));
- prologue_end = min (prologue_end, prologue_start + DEFAULT_SEARCH_LIMIT);
- decode_prologue (prologue_start, prologue_end, &prologue_end, &framesize,
- fi, fsr);
- return framesize;
+ return sal.end;
}
-/* Function: init_extra_frame_info
- This function actually figures out the frame address for a given pc and
- sp. This is tricky on the m32r because we sometimes don't use an explicit
- frame pointer, and the previous stack pointer isn't necessarily recorded
- on the stack. The only reliable way to get this info is to
- examine the prologue. */
-
-void
-m32r_init_extra_frame_info (struct frame_info *fi)
+struct m32r_unwind_cache
+{
+ /* The previous frame's inner most stack address. Used as this
+ frame ID's stack_addr. */
+ CORE_ADDR prev_sp;
+ /* The frame's base, optionally used by the high-level debug info. */
+ CORE_ADDR base;
+ int size;
+ /* How far the SP and r13 (FP) have been offset from the start of
+ the stack frame (as defined by the previous frame's stack
+ pointer). */
+ LONGEST sp_offset;
+ LONGEST r13_offset;
+ int uses_frame;
+ /* Table indicating the location of each and every register. */
+ struct trad_frame_saved_reg *saved_regs;
+};
+
+/* Put here the code to store, into fi->saved_regs, the addresses of
+ the saved registers of frame described by FRAME_INFO. This
+ includes special registers such as pc and fp saved in special ways
+ in the stack frame. sp is even more special: the address we return
+ for it IS the sp for the next frame. */
+
+static struct m32r_unwind_cache *
+m32r_frame_unwind_cache (struct frame_info *next_frame,
+ void **this_prologue_cache)
{
- int reg;
+ CORE_ADDR pc, scan_limit;
+ ULONGEST prev_sp;
+ ULONGEST this_base;
+ unsigned long op, op2;
+ int i;
+ struct m32r_unwind_cache *info;
- if (fi->next)
- fi->pc = FRAME_SAVED_PC (fi->next);
- memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs);
+ if ((*this_prologue_cache))
+ return (*this_prologue_cache);
- if (DEPRECATED_PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
- {
- /* We need to setup fi->frame here because run_stack_dummy gets it wrong
- by assuming it's always FP. */
- fi->frame = deprecated_read_register_dummy (fi->pc, fi->frame,
- SP_REGNUM);
- fi->framesize = 0;
- return;
- }
- else
- {
- fi->using_frame_pointer = 0;
- fi->framesize = m32r_scan_prologue (fi, &fi->fsr);
-
- if (!fi->next)
- if (fi->using_frame_pointer)
- {
- fi->frame = read_register (FP_REGNUM);
- }
- else
- fi->frame = read_register (SP_REGNUM);
- else
- /* fi->next means this is not the innermost frame */ if (fi->using_frame_pointer)
- /* we have an FP */
- if (fi->next->fsr.regs[FP_REGNUM] != 0) /* caller saved our FP */
- fi->frame = read_memory_integer (fi->next->fsr.regs[FP_REGNUM], 4);
- for (reg = 0; reg < NUM_REGS; reg++)
- if (fi->fsr.regs[reg] != 0)
- fi->fsr.regs[reg] = fi->frame + fi->framesize - fi->fsr.regs[reg];
- }
-}
+ info = FRAME_OBSTACK_ZALLOC (struct m32r_unwind_cache);
+ (*this_prologue_cache) = info;
+ info->saved_regs = trad_frame_alloc_saved_regs (next_frame);
-/* Function: m32r_virtual_frame_pointer
- Return the register that the function uses for a frame pointer,
- plus any necessary offset to be applied to the register before
- any frame pointer offsets. */
+ info->size = 0;
+ info->sp_offset = 0;
+ info->uses_frame = 0;
-void
-m32r_virtual_frame_pointer (CORE_ADDR pc, long *reg, long *offset)
-{
- struct frame_info fi;
+ scan_limit = frame_pc_unwind (next_frame);
+ for (pc = frame_func_unwind (next_frame);
+ pc > 0 && pc < scan_limit; pc += 2)
+ {
+ if ((pc & 2) == 0)
+ {
+ op = get_frame_memory_unsigned (next_frame, pc, 4);
+ if ((op & 0x80000000) == 0x80000000)
+ {
+ /* 32-bit instruction */
+ if ((op & 0xffff0000) == 0x8faf0000)
+ {
+ /* add3 sp,sp,xxxx */
+ short n = op & 0xffff;
+ info->sp_offset += n;
+ }
+ else if (((op >> 8) == 0xe4)
+ && get_frame_memory_unsigned (next_frame, pc + 2,
+ 2) == 0x0f24)
+ {
+ /* ld24 r4, xxxxxx; sub sp, r4 */
+ unsigned long n = op & 0xffffff;
+ info->sp_offset += n;
+ pc += 2; /* skip sub instruction */
+ }
- /* Set up a dummy frame_info. */
- fi.next = NULL;
- fi.prev = NULL;
- fi.frame = 0;
- fi.pc = pc;
+ if (pc == scan_limit)
+ scan_limit += 2; /* extend the search */
+ pc += 2; /* skip the immediate data */
+ continue;
+ }
+ }
- /* Analyze the prolog and fill in the extra info. */
- m32r_init_extra_frame_info (&fi);
+ /* 16-bit instructions */
+ op = get_frame_memory_unsigned (next_frame, pc, 2) & 0x7fff;
+ if ((op & 0xf0ff) == 0x207f)
+ {
+ /* st rn, @-sp */
+ int regno = ((op >> 8) & 0xf);
+ info->sp_offset -= 4;
+ info->saved_regs[regno].addr = info->sp_offset;
+ }
+ else if ((op & 0xff00) == 0x4f00)
+ {
+ /* addi sp, xx */
+ int n = (gdb_byte) (op & 0xff);
+ info->sp_offset += n;
+ }
+ else if (op == 0x1d8f)
+ {
+ /* mv fp, sp */
+ info->uses_frame = 1;
+ info->r13_offset = info->sp_offset;
+ break; /* end of stack adjustments */
+ }
+ else if ((op & 0xfff0) == 0x10f0)
+ {
+ /* end of prologue if this is a trap instruction */
+ break; /* end of stack adjustments */
+ }
+ }
+ info->size = -info->sp_offset;
- /* Results will tell us which type of frame it uses. */
- if (fi.using_frame_pointer)
+ /* Compute the previous frame's stack pointer (which is also the
+ frame's ID's stack address), and this frame's base pointer. */
+ if (info->uses_frame)
{
- *reg = FP_REGNUM;
- *offset = 0;
+ /* The SP was moved to the FP. This indicates that a new frame
+ was created. Get THIS frame's FP value by unwinding it from
+ the next frame. */
+ this_base = frame_unwind_register_unsigned (next_frame, M32R_FP_REGNUM);
+ /* The FP points at the last saved register. Adjust the FP back
+ to before the first saved register giving the SP. */
+ prev_sp = this_base + info->size;
}
else
{
- *reg = SP_REGNUM;
- *offset = 0;
+ /* Assume that the FP is this frame's SP but with that pushed
+ stack space added back. */
+ this_base = frame_unwind_register_unsigned (next_frame, M32R_SP_REGNUM);
+ prev_sp = this_base + info->size;
}
-}
-/* Function: find_callers_reg
- Find REGNUM on the stack. Otherwise, it's in an active register. One thing
- we might want to do here is to check REGNUM against the clobber mask, and
- somehow flag it as invalid if it isn't saved on the stack somewhere. This
- would provide a graceful failure mode when trying to get the value of
- caller-saves registers for an inner frame. */
+ /* Convert that SP/BASE into real addresses. */
+ info->prev_sp = prev_sp;
+ info->base = this_base;
-CORE_ADDR
-m32r_find_callers_reg (struct frame_info *fi, int regnum)
-{
- for (; fi; fi = fi->next)
- if (DEPRECATED_PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
- return deprecated_read_register_dummy (fi->pc, fi->frame, regnum);
- else if (fi->fsr.regs[regnum] != 0)
- return read_memory_integer (fi->fsr.regs[regnum],
- REGISTER_RAW_SIZE (regnum));
- return read_register (regnum);
-}
+ /* Adjust all the saved registers so that they contain addresses and
+ not offsets. */
+ for (i = 0; i < NUM_REGS - 1; i++)
+ if (trad_frame_addr_p (info->saved_regs, i))
+ info->saved_regs[i].addr = (info->prev_sp + info->saved_regs[i].addr);
-/* Function: frame_chain
- Given a GDB frame, determine the address of the calling function's frame.
- This will be used to create a new GDB frame struct, and then
- INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
- For m32r, we save the frame size when we initialize the frame_info. */
+ /* The call instruction moves the caller's PC in the callee's LR.
+ Since this is an unwind, do the reverse. Copy the location of LR
+ into PC (the address / regnum) so that a request for PC will be
+ converted into a request for the LR. */
+ info->saved_regs[M32R_PC_REGNUM] = info->saved_regs[LR_REGNUM];
-CORE_ADDR
-m32r_frame_chain (struct frame_info *fi)
-{
- CORE_ADDR fn_start, callers_pc, fp;
-
- /* is this a dummy frame? */
- if (DEPRECATED_PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
- return fi->frame; /* dummy frame same as caller's frame */
-
- /* is caller-of-this a dummy frame? */
- callers_pc = FRAME_SAVED_PC (fi); /* find out who called us: */
- fp = m32r_find_callers_reg (fi, FP_REGNUM);
- if (DEPRECATED_PC_IN_CALL_DUMMY (callers_pc, fp, fp))
- return fp; /* dummy frame's frame may bear no relation to ours */
-
- if (find_pc_partial_function (fi->pc, 0, &fn_start, 0))
- if (fn_start == entry_point_address ())
- return 0; /* in _start fn, don't chain further */
- if (fi->framesize == 0)
- {
- printf_filtered ("cannot determine frame size @ %s , pc(%s)\n",
- paddr (fi->frame),
- paddr (fi->pc));
- return 0;
- }
- insn_debug (("m32rx frame %08x\n", fi->frame + fi->framesize));
- return fi->frame + fi->framesize;
-}
+ /* The previous frame's SP needed to be computed. Save the computed
+ value. */
+ trad_frame_set_value (info->saved_regs, M32R_SP_REGNUM, prev_sp);
-/* Function: push_return_address (pc)
- Set up the return address for the inferior function call.
- Necessary for targets that don't actually execute a JSR/BSR instruction
- (ie. when using an empty CALL_DUMMY) */
+ return info;
+}
-CORE_ADDR
-m32r_push_return_address (CORE_ADDR pc, CORE_ADDR sp)
+static CORE_ADDR
+m32r_read_pc (ptid_t ptid)
{
- write_register (RP_REGNUM, CALL_DUMMY_ADDRESS ());
- return sp;
+ ptid_t save_ptid;
+ ULONGEST pc;
+
+ save_ptid = inferior_ptid;
+ inferior_ptid = ptid;
+ regcache_cooked_read_unsigned (current_regcache, M32R_PC_REGNUM, &pc);
+ inferior_ptid = save_ptid;
+ return pc;
}
-
-/* Function: pop_frame
- Discard from the stack the innermost frame,
- restoring all saved registers. */
-
-struct frame_info *
-m32r_pop_frame (struct frame_info *frame)
+static void
+m32r_write_pc (CORE_ADDR val, ptid_t ptid)
{
- int regnum;
+ ptid_t save_ptid;
- if (DEPRECATED_PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
- generic_pop_dummy_frame ();
- else
- {
- for (regnum = 0; regnum < NUM_REGS; regnum++)
- if (frame->fsr.regs[regnum] != 0)
- write_register (regnum,
- read_memory_integer (frame->fsr.regs[regnum], 4));
-
- write_register (PC_REGNUM, FRAME_SAVED_PC (frame));
- write_register (SP_REGNUM, read_register (FP_REGNUM));
- if (read_register (PSW_REGNUM) & 0x80)
- write_register (SPU_REGNUM, read_register (SP_REGNUM));
- else
- write_register (SPI_REGNUM, read_register (SP_REGNUM));
- }
- flush_cached_frames ();
- return NULL;
+ save_ptid = inferior_ptid;
+ inferior_ptid = ptid;
+ write_register (M32R_PC_REGNUM, val);
+ inferior_ptid = save_ptid;
}
-/* Function: frame_saved_pc
- Find the caller of this frame. We do this by seeing if RP_REGNUM is saved
- in the stack anywhere, otherwise we get it from the registers. */
-
-CORE_ADDR
-m32r_frame_saved_pc (struct frame_info *fi)
+static CORE_ADDR
+m32r_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
{
- if (DEPRECATED_PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
- return deprecated_read_register_dummy (fi->pc, fi->frame, PC_REGNUM);
- else
- return m32r_find_callers_reg (fi, RP_REGNUM);
+ return frame_unwind_register_unsigned (next_frame, M32R_SP_REGNUM);
}
-/* Function: push_arguments
- Setup the function arguments for calling a function in the inferior.
-
- On the Mitsubishi M32R architecture, there are four registers (R0 to R3)
- which are dedicated for passing function arguments. Up to the first
- four arguments (depending on size) may go into these registers.
- The rest go on the stack.
-
- Arguments that are smaller than 4 bytes will still take up a whole
- register or a whole 32-bit word on the stack, and will be
- right-justified in the register or the stack word. This includes
- chars, shorts, and small aggregate types.
-
- Arguments of 8 bytes size are split between two registers, if
- available. If only one register is available, the argument will
- be split between the register and the stack. Otherwise it is
- passed entirely on the stack. Aggregate types with sizes between
- 4 and 8 bytes are passed entirely on the stack, and are left-justified
- within the double-word (as opposed to aggregates smaller than 4 bytes
- which are right-justified).
-
- Aggregates of greater than 8 bytes are first copied onto the stack,
- and then a pointer to the copy is passed in the place of the normal
- argument (either in a register if available, or on the stack).
-
- Functions that must return an aggregate type can return it in the
- normal return value registers (R0 and R1) if its size is 8 bytes or
- less. For larger return values, the caller must allocate space for
- the callee to copy the return value to. A pointer to this space is
- passed as an implicit first argument, always in R0. */
-CORE_ADDR
-m32r_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
- unsigned char struct_return, CORE_ADDR struct_addr)
+static CORE_ADDR
+m32r_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 stack_offset, stack_alloc;
- int argreg;
+ int argreg = ARG1_REGNUM;
int argnum;
struct type *type;
+ enum type_code typecode;
CORE_ADDR regval;
- char *val;
- char valbuf[4];
+ gdb_byte *val;
+ gdb_byte valbuf[MAX_REGISTER_SIZE];
int len;
int odd_sized_struct;
/* first force sp to a 4-byte alignment */
sp = sp & ~3;
- argreg = ARG0_REGNUM;
- /* The "struct return pointer" pseudo-argument goes in R0 */
+ /* Set the return address. For the m32r, the return breakpoint is
+ always at BP_ADDR. */
+ regcache_cooked_write_unsigned (regcache, LR_REGNUM, bp_addr);
+
+ /* If STRUCT_RETURN is true, then the struct return address (in
+ STRUCT_ADDR) will consume the first argument-passing register.
+ Both adjust the register count and store that value. */
if (struct_return)
- write_register (argreg++, struct_addr);
+ {
+ regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
+ argreg++;
+ }
/* Now make sure there's space on the stack */
- for (argnum = 0, stack_alloc = 0;
- argnum < nargs; argnum++)
- stack_alloc += ((TYPE_LENGTH (VALUE_TYPE (args[argnum])) + 3) & ~3);
+ for (argnum = 0, stack_alloc = 0; argnum < nargs; argnum++)
+ stack_alloc += ((TYPE_LENGTH (value_type (args[argnum])) + 3) & ~3);
sp -= stack_alloc; /* make room on stack for args */
-
- /* Now load as many as possible of the first arguments into
- registers, and push the rest onto the stack. There are 16 bytes
- in four registers available. Loop thru args from first to last. */
-
- argreg = ARG0_REGNUM;
for (argnum = 0, stack_offset = 0; argnum < nargs; argnum++)
{
- type = VALUE_TYPE (args[argnum]);
+ type = value_type (args[argnum]);
+ typecode = TYPE_CODE (type);
len = TYPE_LENGTH (type);
+
memset (valbuf, 0, sizeof (valbuf));
- if (len < 4)
- { /* value gets right-justified in the register or stack word */
- memcpy (valbuf + (4 - len),
- (char *) VALUE_CONTENTS (args[argnum]), len);
+
+ /* Passes structures that do not fit in 2 registers by reference. */
+ if (len > 8
+ && (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION))
+ {
+ store_unsigned_integer (valbuf, 4, VALUE_ADDRESS (args[argnum]));
+ typecode = TYPE_CODE_PTR;
+ len = 4;
+ val = valbuf;
+ }
+ else if (len < 4)
+ {
+ /* value gets right-justified in the register or stack word */
+ memcpy (valbuf + (register_size (gdbarch, argreg) - len),
+ (gdb_byte *) value_contents (args[argnum]), len);
val = valbuf;
}
else
- val = (char *) VALUE_CONTENTS (args[argnum]);
+ val = (gdb_byte *) value_contents (args[argnum]);
- if (len > 4 && (len & 3) != 0)
- odd_sized_struct = 1; /* such structs go entirely on stack */
- else
- odd_sized_struct = 0;
while (len > 0)
{
- if (argreg > ARGLAST_REGNUM || odd_sized_struct)
- { /* must go on the stack */
+ if (argreg > ARGN_REGNUM)
+ {
+ /* must go on the stack */
write_memory (sp + stack_offset, val, 4);
stack_offset += 4;
}
- /* NOTE WELL!!!!! This is not an "else if" clause!!!
- That's because some *&^%$ things get passed on the stack
- AND in the registers! */
- if (argreg <= ARGLAST_REGNUM)
- { /* there's room in a register */
- regval = extract_address (val, REGISTER_RAW_SIZE (argreg));
- write_register (argreg++, regval);
+ else if (argreg <= ARGN_REGNUM)
+ {
+ /* there's room in a register */
+ regval =
+ extract_unsigned_integer (val,
+ register_size (gdbarch, argreg));
+ regcache_cooked_write_unsigned (regcache, argreg++, regval);
}
+
/* Store the value 4 bytes at a time. This means that things
larger than 4 bytes may go partly in registers and partly
on the stack. */
- len -= REGISTER_RAW_SIZE (argreg);
- val += REGISTER_RAW_SIZE (argreg);
+ len -= register_size (gdbarch, argreg);
+ val += register_size (gdbarch, argreg);
}
}
+
+ /* Finally, update the SP register. */
+ regcache_cooked_write_unsigned (regcache, M32R_SP_REGNUM, sp);
+
return sp;
}
-/* Function: fix_call_dummy
- If there is real CALL_DUMMY code (eg. on the stack), this function
- has the responsability to insert the address of the actual code that
- is the target of the target function call. */
-void
-m32r_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
- struct value **args, struct type *type, int gcc_p)
+/* Given a return value in `regbuf' with a type `valtype',
+ extract and copy its value into `valbuf'. */
+
+static void
+m32r_extract_return_value (struct type *type, struct regcache *regcache,
+ void *dst)
{
- /* ld24 r8, <(imm24) fun> */
- *(unsigned long *) (dummy) = (fun & 0x00ffffff) | 0xe8000000;
+ bfd_byte *valbuf = dst;
+ int len = TYPE_LENGTH (type);
+ ULONGEST tmp;
+
+ /* By using store_unsigned_integer we avoid having to do
+ anything special for small big-endian values. */
+ regcache_cooked_read_unsigned (regcache, RET1_REGNUM, &tmp);
+ store_unsigned_integer (valbuf, (len > 4 ? len - 4 : len), tmp);
+
+ /* Ignore return values more than 8 bytes in size because the m32r
+ returns anything more than 8 bytes in the stack. */
+ if (len > 4)
+ {
+ regcache_cooked_read_unsigned (regcache, RET1_REGNUM + 1, &tmp);
+ store_unsigned_integer (valbuf + len - 4, 4, tmp);
+ }
}
+enum return_value_convention
+m32r_return_value (struct gdbarch *gdbarch, struct type *valtype,
+ struct regcache *regcache, gdb_byte *readbuf,
+ const gdb_byte *writebuf)
+{
+ if (TYPE_LENGTH (valtype) > 8)
+ return RETURN_VALUE_STRUCT_CONVENTION;
+ else
+ {
+ if (readbuf != NULL)
+ m32r_extract_return_value (valtype, regcache, readbuf);
+ if (writebuf != NULL)
+ m32r_store_return_value (valtype, regcache, writebuf);
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
+}
-/* Function: m32r_write_sp
- Because SP is really a read-only register that mirrors either SPU or SPI,
- we must actually write one of those two as well, depending on PSW. */
-void
-m32r_write_sp (CORE_ADDR val)
+
+static CORE_ADDR
+m32r_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
{
- unsigned long psw = read_register (PSW_REGNUM);
+ return frame_unwind_register_unsigned (next_frame, M32R_PC_REGNUM);
+}
- if (psw & 0x80) /* stack mode: user or interrupt */
- write_register (SPU_REGNUM, val);
- else
- write_register (SPI_REGNUM, val);
- write_register (SP_REGNUM, val);
+/* Given a GDB frame, determine the address of the calling function's
+ frame. This will be used to create a new GDB frame struct. */
+
+static void
+m32r_frame_this_id (struct frame_info *next_frame,
+ void **this_prologue_cache, struct frame_id *this_id)
+{
+ struct m32r_unwind_cache *info
+ = m32r_frame_unwind_cache (next_frame, this_prologue_cache);
+ CORE_ADDR base;
+ CORE_ADDR func;
+ struct minimal_symbol *msym_stack;
+ struct frame_id id;
+
+ /* The FUNC is easy. */
+ func = frame_func_unwind (next_frame);
+
+ /* Check if the stack is empty. */
+ msym_stack = lookup_minimal_symbol ("_stack", NULL, NULL);
+ if (msym_stack && info->base == SYMBOL_VALUE_ADDRESS (msym_stack))
+ return;
+
+ /* Hopefully the prologue analysis either correctly determined the
+ frame's base (which is the SP from the previous frame), or set
+ that base to "NULL". */
+ base = info->prev_sp;
+ if (base == 0)
+ return;
+
+ id = frame_id_build (base, func);
+ (*this_id) = id;
+}
+
+static void
+m32r_frame_prev_register (struct frame_info *next_frame,
+ void **this_prologue_cache,
+ int regnum, int *optimizedp,
+ enum lval_type *lvalp, CORE_ADDR *addrp,
+ int *realnump, gdb_byte *bufferp)
+{
+ struct m32r_unwind_cache *info
+ = m32r_frame_unwind_cache (next_frame, this_prologue_cache);
+ trad_frame_get_prev_register (next_frame, info->saved_regs, regnum,
+ optimizedp, lvalp, addrp, realnump, bufferp);
+}
+
+static const struct frame_unwind m32r_frame_unwind = {
+ NORMAL_FRAME,
+ m32r_frame_this_id,
+ m32r_frame_prev_register
+};
+
+static const struct frame_unwind *
+m32r_frame_sniffer (struct frame_info *next_frame)
+{
+ return &m32r_frame_unwind;
+}
+
+static CORE_ADDR
+m32r_frame_base_address (struct frame_info *next_frame, void **this_cache)
+{
+ struct m32r_unwind_cache *info
+ = m32r_frame_unwind_cache (next_frame, this_cache);
+ return info->base;
+}
+
+static const struct frame_base m32r_frame_base = {
+ &m32r_frame_unwind,
+ m32r_frame_base_address,
+ m32r_frame_base_address,
+ m32r_frame_base_address
+};
+
+/* Assuming NEXT_FRAME->prev 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 the PC match the dummy frame's
+ breakpoint. */
+
+static struct frame_id
+m32r_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_id_build (m32r_unwind_sp (gdbarch, next_frame),
+ frame_pc_unwind (next_frame));
+}
+
+
+static gdbarch_init_ftype m32r_gdbarch_init;
+
+static struct gdbarch *
+m32r_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
+{
+ struct gdbarch *gdbarch;
+ struct gdbarch_tdep *tdep;
+
+ /* If there is already a candidate, use it. */
+ arches = gdbarch_list_lookup_by_info (arches, &info);
+ if (arches != NULL)
+ return arches->gdbarch;
+
+ /* Allocate space for the new architecture. */
+ tdep = XMALLOC (struct gdbarch_tdep);
+ gdbarch = gdbarch_alloc (&info, tdep);
+
+ set_gdbarch_read_pc (gdbarch, m32r_read_pc);
+ set_gdbarch_write_pc (gdbarch, m32r_write_pc);
+ set_gdbarch_unwind_sp (gdbarch, m32r_unwind_sp);
+
+ set_gdbarch_num_regs (gdbarch, M32R_NUM_REGS);
+ set_gdbarch_sp_regnum (gdbarch, M32R_SP_REGNUM);
+ set_gdbarch_register_name (gdbarch, m32r_register_name);
+ set_gdbarch_register_type (gdbarch, m32r_register_type);
+
+ set_gdbarch_push_dummy_call (gdbarch, m32r_push_dummy_call);
+ set_gdbarch_return_value (gdbarch, m32r_return_value);
+
+ set_gdbarch_skip_prologue (gdbarch, m32r_skip_prologue);
+ set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
+ set_gdbarch_breakpoint_from_pc (gdbarch, m32r_breakpoint_from_pc);
+ set_gdbarch_memory_insert_breakpoint (gdbarch,
+ m32r_memory_insert_breakpoint);
+ set_gdbarch_memory_remove_breakpoint (gdbarch,
+ m32r_memory_remove_breakpoint);
+
+ set_gdbarch_frame_align (gdbarch, m32r_frame_align);
+
+ frame_base_set_default (gdbarch, &m32r_frame_base);
+
+ /* Methods for saving / extracting a dummy frame's ID. The ID's
+ stack address must match the SP value returned by
+ PUSH_DUMMY_CALL, and saved by generic_save_dummy_frame_tos. */
+ set_gdbarch_unwind_dummy_id (gdbarch, m32r_unwind_dummy_id);
+
+ /* Return the unwound PC value. */
+ set_gdbarch_unwind_pc (gdbarch, m32r_unwind_pc);
+
+ set_gdbarch_print_insn (gdbarch, print_insn_m32r);
+
+ /* Hook in ABI-specific overrides, if they have been registered. */
+ gdbarch_init_osabi (info, gdbarch);
+
+ /* Hook in the default unwinders. */
+ frame_unwind_append_sniffer (gdbarch, m32r_frame_sniffer);
+
+ return gdbarch;
}
void
_initialize_m32r_tdep (void)
{
- tm_print_insn = print_insn_m32r;
+ register_gdbarch_init (bfd_arch_m32r, m32r_gdbarch_init);
}