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|
/* Target-dependent code for Renesas M32R, for GDB.
Copyright (C) 1996-2023 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
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 "defs.h"
#include "frame.h"
#include "frame-unwind.h"
#include "frame-base.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "gdbcmd.h"
#include "gdbcore.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 "m32r-tdep.h"
#include <algorithm>
/* The size of the argument registers (r0 - r3) in bytes. */
#define M32R_ARG_REGISTER_SIZE 4
/* Local functions */
static CORE_ADDR
m32r_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
{
/* Align to the size of an instruction (so that they can safely be
pushed onto the stack. */
return sp & ~3;
}
/* 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 (struct gdbarch *gdbarch,
struct bp_target_info *bp_tgt)
{
CORE_ADDR addr = bp_tgt->placed_address = bp_tgt->reqstd_address;
int val;
gdb_byte buf[4];
gdb_byte contents_cache[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 */
memcpy (bp_tgt->shadow_contents, contents_cache, 4);
bp_tgt->shadow_len = 4;
/* Determine appropriate breakpoint contents and size for this address. */
if (gdbarch_byte_order (gdbarch) == 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;
}
static int
m32r_memory_remove_breakpoint (struct gdbarch *gdbarch,
struct bp_target_info *bp_tgt)
{
CORE_ADDR addr = bp_tgt->placed_address;
int val;
gdb_byte buf[4];
gdb_byte *contents_cache = bp_tgt->shadow_contents;
buf[0] = contents_cache[0];
buf[1] = contents_cache[1];
buf[2] = contents_cache[2];
buf[3] = contents_cache[3];
/* Remove parallel bit. */
if (gdbarch_byte_order (gdbarch) == 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_raw_memory (addr & 0xfffffffc, buf, 4);
return val;
}
/* Implement the breakpoint_kind_from_pc gdbarch method. */
static int
m32r_breakpoint_kind_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr)
{
if ((*pcptr & 3) == 0)
return 4;
else
return 2;
}
/* Implement the sw_breakpoint_from_kind gdbarch method. */
static const gdb_byte *
m32r_sw_breakpoint_from_kind (struct gdbarch *gdbarch, int kind, int *size)
{
static gdb_byte be_bp_entry[] = {
0x10, 0xf1, 0x70, 0x00
}; /* dpt -> nop */
static gdb_byte le_bp_entry[] = {
0x00, 0x70, 0xf1, 0x10
}; /* dpt -> nop */
*size = kind;
/* Determine appropriate breakpoint. */
if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
return be_bp_entry;
else
{
if (kind == 4)
return le_bp_entry;
else
return le_bp_entry + 2;
}
}
static const char * const 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 (struct gdbarch *gdbarch, int reg_nr)
{
gdb_static_assert (ARRAY_SIZE (m32r_register_names) == M32R_NUM_REGS);
return m32r_register_names[reg_nr];
}
/* 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 (gdbarch)->builtin_func_ptr;
else if (reg_nr == M32R_SP_REGNUM || reg_nr == M32R_FP_REGNUM)
return builtin_type (gdbarch)->builtin_data_ptr;
else
return builtin_type (gdbarch)->builtin_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
m32r_store_return_value (struct type *type, struct regcache *regcache,
const gdb_byte *valbuf)
{
struct gdbarch *gdbarch = regcache->arch ();
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR regval;
int len = type->length ();
regval = extract_unsigned_integer (valbuf, len > 4 ? 4 : len, byte_order);
regcache_cooked_write_unsigned (regcache, RET1_REGNUM, regval);
if (len > 4)
{
regval = extract_unsigned_integer (valbuf + 4,
len - 4, byte_order);
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 (struct gdbarch *gdbarch,
CORE_ADDR start_pc, CORE_ADDR scan_limit,
CORE_ADDR *pl_endptr, unsigned long *framelength)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
unsigned long framesize;
int insn;
int op1;
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;
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, byte_order, &return_value))
return -1;
insn = read_memory_unsigned_integer (current_pc, 2, byte_order);
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)
{
/* Decode this instruction further. */
insn &= 0x7fff;
}
else
{
if (insn & 0x8000)
{
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, byte_order,
&return_value))
return -1;
if (insn == 0x8faf) /* add3 sp, sp, xxxx */
/* add 16 bit sign-extended offset */
{
framesize +=
-((short) read_memory_unsigned_integer (current_pc,
2, byte_order));
}
else
{
if (((insn >> 8) == 0xe4) /* ld24 r4, xxxxxx; sub sp, r4 */
&& safe_read_memory_integer (current_pc + 2,
2, byte_order,
&return_value)
&& read_memory_unsigned_integer (current_pc + 2,
2, byte_order)
== 0x0f24)
{
/* Subtract 24 bit sign-extended negative-offset. */
insn = read_memory_unsigned_integer (current_pc - 2,
4, byte_order);
if (insn & 0x00800000) /* sign extend */
insn |= 0xff000000; /* negative */
else
insn &= 0x00ffffff; /* positive */
framesize += insn;
}
}
after_push = current_pc + 2;
continue;
}
}
op1 = insn & 0xf000; /* Isolate just the first nibble. */
if ((insn & 0xf0ff) == 0x207f)
{ /* st reg, @-sp */
framesize += 4;
after_prologue = 0;
continue;
}
if ((insn >> 8) == 0x4f) /* addi sp, xx */
/* Add 8 bit sign-extended offset. */
{
int stack_adjust = (signed char) (insn & 0xff);
/* there are probably two of these stack adjustments:
1) A negative one in the prologue, and
2) A positive one in the epilogue.
We are only interested in the first one. */
if (stack_adjust < 0)
{
framesize -= stack_adjust;
after_prologue = 0;
/* A frameless function may have no "mv fp, sp".
In that case, this is the end of the prologue. */
after_stack_adjust = current_pc + 2;
}
continue;
}
if (insn == 0x1d8f)
{ /* mv fp, sp */
after_prologue = current_pc + 2;
break; /* end of stack adjustments */
}
/* Nop looks like a branch, continue explicitly. */
if (insn == 0x7000)
{
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))
{
after_prologue = current_pc;
continue;
}
/* Some of the branch instructions are mixed with other types. */
if (op1 == 0x1000)
{
int subop = insn & 0x0ff0;
if ((subop == 0x0ec0) || (subop == 0x0fc0))
{
after_prologue = current_pc;
continue; /* jmp , jl */
}
}
}
if (framelength)
*framelength = framesize;
if (current_pc >= scan_limit)
{
if (pl_endptr)
{
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;
}
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
/* 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 0;
}
if (after_prologue == 0)
after_prologue = current_pc;
if (pl_endptr)
*pl_endptr = after_prologue;
return 0;
} /* decode_prologue */
/* Function: skip_prologue
Find end of function prologue. */
#define DEFAULT_SEARCH_LIMIT 128
static CORE_ADDR
m32r_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR func_addr, func_end;
struct symtab_and_line sal;
LONGEST return_value;
/* See what the symbol table says. */
if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
{
sal = find_pc_line (func_addr, 0);
if (sal.line != 0 && sal.end <= func_end)
{
func_end = sal.end;
}
else
/* Either there's no line info, or the line after the prologue is after
the end of the function. In this case, there probably isn't a
prologue. */
{
func_end = std::min (func_end, func_addr + DEFAULT_SEARCH_LIMIT);
}
}
else
func_end = pc + DEFAULT_SEARCH_LIMIT;
/* If pc's location is not readable, just quit. */
if (!safe_read_memory_integer (pc, 4, byte_order, &return_value))
return pc;
/* Find the end of prologue. */
if (decode_prologue (gdbarch, pc, func_end, &sal.end, NULL) < 0)
return pc;
return sal.end;
}
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. */
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 (frame_info_ptr this_frame,
void **this_prologue_cache)
{
CORE_ADDR pc, scan_limit;
ULONGEST prev_sp;
ULONGEST this_base;
unsigned long op;
int i;
struct m32r_unwind_cache *info;
if ((*this_prologue_cache))
return (struct m32r_unwind_cache *) (*this_prologue_cache);
info = FRAME_OBSTACK_ZALLOC (struct m32r_unwind_cache);
(*this_prologue_cache) = info;
info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
info->size = 0;
info->sp_offset = 0;
info->uses_frame = 0;
scan_limit = get_frame_pc (this_frame);
for (pc = get_frame_func (this_frame);
pc > 0 && pc < scan_limit; pc += 2)
{
if ((pc & 2) == 0)
{
op = get_frame_memory_unsigned (this_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 (this_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 */
}
if (pc == scan_limit)
scan_limit += 2; /* extend the search */
pc += 2; /* skip the immediate data */
continue;
}
}
/* 16-bit instructions */
op = get_frame_memory_unsigned (this_frame, pc, 2) & 0x7fff;
if ((op & 0xf0ff) == 0x207f)
{
/* st rn, @-sp */
int regno = ((op >> 8) & 0xf);
info->sp_offset -= 4;
info->saved_regs[regno].set_addr (info->sp_offset);
}
else if ((op & 0xff00) == 0x4f00)
{
/* addi sp, xx */
int n = (signed char) (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;
/* 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)
{
/* 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 = get_frame_register_unsigned (this_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
{
/* Assume that the FP is this frame's SP but with that pushed
stack space added back. */
this_base = get_frame_register_unsigned (this_frame, M32R_SP_REGNUM);
prev_sp = this_base + info->size;
}
/* Convert that SP/BASE into real addresses. */
info->prev_sp = prev_sp;
info->base = this_base;
/* Adjust all the saved registers so that they contain addresses and
not offsets. */
for (i = 0; i < gdbarch_num_regs (get_frame_arch (this_frame)) - 1; i++)
if (info->saved_regs[i].is_addr ())
info->saved_regs[i].set_addr (info->prev_sp
+ info->saved_regs[i].addr ());
/* 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];
/* The previous frame's SP needed to be computed. Save the computed
value. */
info->saved_regs[M32R_SP_REGNUM].set_value (prev_sp);
return info;
}
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,
function_call_return_method return_method,
CORE_ADDR struct_addr)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int stack_offset, stack_alloc;
int argreg = ARG1_REGNUM;
int argnum;
struct type *type;
enum type_code typecode;
CORE_ADDR regval;
gdb_byte *val;
gdb_byte valbuf[M32R_ARG_REGISTER_SIZE];
int len;
/* First force sp to a 4-byte alignment. */
sp = sp & ~3;
/* 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 (return_method == return_method_struct)
{
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 += ((args[argnum]->type ()->length () + 3) & ~3);
sp -= stack_alloc; /* Make room on stack for args. */
for (argnum = 0, stack_offset = 0; argnum < nargs; argnum++)
{
type = args[argnum]->type ();
typecode = type->code ();
len = type->length ();
memset (valbuf, 0, sizeof (valbuf));
/* 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, byte_order,
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]).data (), len);
val = valbuf;
}
else
val = (gdb_byte *) value_contents (args[argnum]).data ();
while (len > 0)
{
if (argreg > ARGN_REGNUM)
{
/* Must go on the stack. */
write_memory (sp + stack_offset, val, 4);
stack_offset += 4;
}
else if (argreg <= ARGN_REGNUM)
{
/* There's room in a register. */
regval =
extract_unsigned_integer (val,
register_size (gdbarch, argreg),
byte_order);
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_size (gdbarch, argreg);
val += register_size (gdbarch, argreg);
}
}
/* Finally, update the SP register. */
regcache_cooked_write_unsigned (regcache, M32R_SP_REGNUM, sp);
return sp;
}
/* 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,
gdb_byte *dst)
{
struct gdbarch *gdbarch = regcache->arch ();
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int len = type->length ();
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 (dst, (len > 4 ? len - 4 : len), byte_order, 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 (dst + len - 4, 4, byte_order, tmp);
}
}
static enum return_value_convention
m32r_return_value (struct gdbarch *gdbarch, struct value *function,
struct type *valtype, struct regcache *regcache,
gdb_byte *readbuf, const gdb_byte *writebuf)
{
if (valtype->length () > 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;
}
}
/* 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 (frame_info_ptr this_frame,
void **this_prologue_cache, struct frame_id *this_id)
{
struct m32r_unwind_cache *info
= m32r_frame_unwind_cache (this_frame, this_prologue_cache);
CORE_ADDR base;
CORE_ADDR func;
struct bound_minimal_symbol msym_stack;
struct frame_id id;
/* The FUNC is easy. */
func = get_frame_func (this_frame);
/* Check if the stack is empty. */
msym_stack = lookup_minimal_symbol ("_stack", NULL, NULL);
if (msym_stack.minsym && info->base == msym_stack.value_address ())
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 struct value *
m32r_frame_prev_register (frame_info_ptr this_frame,
void **this_prologue_cache, int regnum)
{
struct m32r_unwind_cache *info
= m32r_frame_unwind_cache (this_frame, this_prologue_cache);
return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
}
static const struct frame_unwind m32r_frame_unwind = {
"m32r prologue",
NORMAL_FRAME,
default_frame_unwind_stop_reason,
m32r_frame_this_id,
m32r_frame_prev_register,
NULL,
default_frame_sniffer
};
static CORE_ADDR
m32r_frame_base_address (frame_info_ptr this_frame, void **this_cache)
{
struct m32r_unwind_cache *info
= m32r_frame_unwind_cache (this_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
};
static gdbarch_init_ftype m32r_gdbarch_init;
static struct gdbarch *
m32r_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
{
/* 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. */
gdbarch *gdbarch
= gdbarch_alloc (&info, gdbarch_tdep_up (new m32r_gdbarch_tdep));
set_gdbarch_wchar_bit (gdbarch, 16);
set_gdbarch_wchar_signed (gdbarch, 0);
set_gdbarch_num_regs (gdbarch, M32R_NUM_REGS);
set_gdbarch_pc_regnum (gdbarch, M32R_PC_REGNUM);
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_kind_from_pc (gdbarch, m32r_breakpoint_kind_from_pc);
set_gdbarch_sw_breakpoint_from_kind (gdbarch, m32r_sw_breakpoint_from_kind);
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);
/* Hook in ABI-specific overrides, if they have been registered. */
gdbarch_init_osabi (info, gdbarch);
/* Hook in the default unwinders. */
frame_unwind_append_unwinder (gdbarch, &m32r_frame_unwind);
/* Support simple overlay manager. */
set_gdbarch_overlay_update (gdbarch, simple_overlay_update);
return gdbarch;
}
void _initialize_m32r_tdep ();
void
_initialize_m32r_tdep ()
{
gdbarch_register (bfd_arch_m32r, m32r_gdbarch_init);
}
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