binutils-gdb/gdb/trad-frame.c

196 lines
5.6 KiB
C

/* Traditional frame unwind support, for GDB the GNU Debugger.
Copyright (C) 2003-2017 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 "trad-frame.h"
#include "regcache.h"
#include "frame-unwind.h"
#include "value.h"
struct trad_frame_cache
{
struct frame_info *this_frame;
CORE_ADDR this_base;
struct trad_frame_saved_reg *prev_regs;
struct frame_id this_id;
};
struct trad_frame_cache *
trad_frame_cache_zalloc (struct frame_info *this_frame)
{
struct trad_frame_cache *this_trad_cache;
this_trad_cache = FRAME_OBSTACK_ZALLOC (struct trad_frame_cache);
this_trad_cache->prev_regs = trad_frame_alloc_saved_regs (this_frame);
this_trad_cache->this_frame = this_frame;
return this_trad_cache;
}
struct trad_frame_saved_reg *
trad_frame_alloc_saved_regs (struct gdbarch *gdbarch)
{
int regnum;
int numregs = gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
struct trad_frame_saved_reg *this_saved_regs
= FRAME_OBSTACK_CALLOC (numregs, struct trad_frame_saved_reg);
for (regnum = 0; regnum < numregs; regnum++)
{
this_saved_regs[regnum].realreg = regnum;
this_saved_regs[regnum].addr = -1;
}
return this_saved_regs;
}
/* A traditional frame is unwound by analysing the function prologue
and using the information gathered to track registers. For
non-optimized frames, the technique is reliable (just need to check
for all potential instruction sequences). */
struct trad_frame_saved_reg *
trad_frame_alloc_saved_regs (struct frame_info *this_frame)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
return trad_frame_alloc_saved_regs (gdbarch);
}
enum { TF_REG_VALUE = -1, TF_REG_UNKNOWN = -2 };
int
trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
{
return (this_saved_regs[regnum].realreg == TF_REG_VALUE);
}
int
trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
{
return (this_saved_regs[regnum].realreg >= 0
&& this_saved_regs[regnum].addr != -1);
}
int
trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
int regnum)
{
return (this_saved_regs[regnum].realreg >= 0
&& this_saved_regs[regnum].addr == -1);
}
void
trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
int regnum, LONGEST val)
{
/* Make the REALREG invalid, indicating that the ADDR contains the
register's value. */
this_saved_regs[regnum].realreg = TF_REG_VALUE;
this_saved_regs[regnum].addr = val;
}
void
trad_frame_set_reg_value (struct trad_frame_cache *this_trad_cache,
int regnum, LONGEST val)
{
/* External interface for users of trad_frame_cache
(who cannot access the prev_regs object directly). */
trad_frame_set_value (this_trad_cache->prev_regs, regnum, val);
}
void
trad_frame_set_reg_realreg (struct trad_frame_cache *this_trad_cache,
int regnum, int realreg)
{
this_trad_cache->prev_regs[regnum].realreg = realreg;
this_trad_cache->prev_regs[regnum].addr = -1;
}
void
trad_frame_set_reg_addr (struct trad_frame_cache *this_trad_cache,
int regnum, CORE_ADDR addr)
{
this_trad_cache->prev_regs[regnum].addr = addr;
}
void
trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
int regnum)
{
/* Make the REALREG invalid, indicating that the value is not known. */
this_saved_regs[regnum].realreg = TF_REG_UNKNOWN;
this_saved_regs[regnum].addr = -1;
}
struct value *
trad_frame_get_prev_register (struct frame_info *this_frame,
struct trad_frame_saved_reg this_saved_regs[],
int regnum)
{
if (trad_frame_addr_p (this_saved_regs, regnum))
/* The register was saved in memory. */
return frame_unwind_got_memory (this_frame, regnum,
this_saved_regs[regnum].addr);
else if (trad_frame_realreg_p (this_saved_regs, regnum))
return frame_unwind_got_register (this_frame, regnum,
this_saved_regs[regnum].realreg);
else if (trad_frame_value_p (this_saved_regs, regnum))
/* The register's value is available. */
return frame_unwind_got_constant (this_frame, regnum,
this_saved_regs[regnum].addr);
else
return frame_unwind_got_optimized (this_frame, regnum);
}
struct value *
trad_frame_get_register (struct trad_frame_cache *this_trad_cache,
struct frame_info *this_frame,
int regnum)
{
return trad_frame_get_prev_register (this_frame, this_trad_cache->prev_regs,
regnum);
}
void
trad_frame_set_id (struct trad_frame_cache *this_trad_cache,
struct frame_id this_id)
{
this_trad_cache->this_id = this_id;
}
void
trad_frame_get_id (struct trad_frame_cache *this_trad_cache,
struct frame_id *this_id)
{
(*this_id) = this_trad_cache->this_id;
}
void
trad_frame_set_this_base (struct trad_frame_cache *this_trad_cache,
CORE_ADDR this_base)
{
this_trad_cache->this_base = this_base;
}
CORE_ADDR
trad_frame_get_this_base (struct trad_frame_cache *this_trad_cache)
{
return this_trad_cache->this_base;
}