377 lines
11 KiB
C
377 lines
11 KiB
C
/* Target-dependent mdebug code for the ALPHA architecture.
|
||
Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
|
||
2003, 2007, 2008 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 "gdbcore.h"
|
||
#include "block.h"
|
||
#include "gdb_assert.h"
|
||
#include "gdb_string.h"
|
||
#include "trad-frame.h"
|
||
|
||
#include "alpha-tdep.h"
|
||
#include "mdebugread.h"
|
||
|
||
/* FIXME: Some of this code should perhaps be merged with mips. */
|
||
|
||
/* *INDENT-OFF* */
|
||
/* Layout of a stack frame on the alpha:
|
||
|
||
| |
|
||
pdr members: | 7th ... nth arg, |
|
||
| `pushed' by caller. |
|
||
| |
|
||
----------------|-------------------------------|<-- old_sp == vfp
|
||
^ ^ ^ ^ | |
|
||
| | | | | |
|
||
| |localoff | Copies of 1st .. 6th |
|
||
| | | | | argument if necessary. |
|
||
| | | v | |
|
||
| | | --- |-------------------------------|<-- LOCALS_ADDRESS
|
||
| | | | |
|
||
| | | | Locals and temporaries. |
|
||
| | | | |
|
||
| | | |-------------------------------|
|
||
| | | | |
|
||
|-fregoffset | Saved float registers. |
|
||
| | | | F9 |
|
||
| | | | . |
|
||
| | | | . |
|
||
| | | | F2 |
|
||
| | v | |
|
||
| | -------|-------------------------------|
|
||
| | | |
|
||
| | | Saved registers. |
|
||
| | | S6 |
|
||
|-regoffset | . |
|
||
| | | . |
|
||
| | | S0 |
|
||
| | | pdr.pcreg |
|
||
| v | |
|
||
| ----------|-------------------------------|
|
||
| | |
|
||
frameoffset | Argument build area, gets |
|
||
| | 7th ... nth arg for any |
|
||
| | called procedure. |
|
||
v | |
|
||
-------------|-------------------------------|<-- sp
|
||
| |
|
||
*/
|
||
/* *INDENT-ON* */
|
||
|
||
#define PROC_LOW_ADDR(proc) ((proc)->pdr.adr)
|
||
#define PROC_FRAME_OFFSET(proc) ((proc)->pdr.frameoffset)
|
||
#define PROC_FRAME_REG(proc) ((proc)->pdr.framereg)
|
||
#define PROC_REG_MASK(proc) ((proc)->pdr.regmask)
|
||
#define PROC_FREG_MASK(proc) ((proc)->pdr.fregmask)
|
||
#define PROC_REG_OFFSET(proc) ((proc)->pdr.regoffset)
|
||
#define PROC_FREG_OFFSET(proc) ((proc)->pdr.fregoffset)
|
||
#define PROC_PC_REG(proc) ((proc)->pdr.pcreg)
|
||
#define PROC_LOCALOFF(proc) ((proc)->pdr.localoff)
|
||
|
||
/* Locate the mdebug PDR for the given PC. Return null if one can't
|
||
be found; you'll have to fall back to other methods in that case. */
|
||
|
||
static struct mdebug_extra_func_info *
|
||
find_proc_desc (CORE_ADDR pc)
|
||
{
|
||
struct block *b = block_for_pc (pc);
|
||
struct mdebug_extra_func_info *proc_desc = NULL;
|
||
struct symbol *sym = NULL;
|
||
char *sh_name = NULL;
|
||
|
||
if (b)
|
||
{
|
||
CORE_ADDR startaddr;
|
||
find_pc_partial_function (pc, &sh_name, &startaddr, NULL);
|
||
|
||
if (startaddr > BLOCK_START (b))
|
||
/* This is the "pathological" case referred to in a comment in
|
||
print_frame_info. It might be better to move this check into
|
||
symbol reading. */
|
||
sym = NULL;
|
||
else
|
||
sym = lookup_symbol (MDEBUG_EFI_SYMBOL_NAME, b, LABEL_DOMAIN, 0);
|
||
}
|
||
|
||
if (sym)
|
||
{
|
||
proc_desc = (struct mdebug_extra_func_info *) SYMBOL_VALUE (sym);
|
||
|
||
/* Correct incorrect setjmp procedure descriptor from the library
|
||
to make backtrace through setjmp work. */
|
||
if (proc_desc->pdr.pcreg == 0
|
||
&& strcmp (sh_name, "setjmp") == 0)
|
||
{
|
||
proc_desc->pdr.pcreg = ALPHA_RA_REGNUM;
|
||
proc_desc->pdr.regmask = 0x80000000;
|
||
proc_desc->pdr.regoffset = -4;
|
||
}
|
||
|
||
/* If we never found a PDR for this function in symbol reading,
|
||
then examine prologues to find the information. */
|
||
if (proc_desc->pdr.framereg == -1)
|
||
proc_desc = NULL;
|
||
}
|
||
|
||
return proc_desc;
|
||
}
|
||
|
||
/* This returns the PC of the first inst after the prologue. If we can't
|
||
find the prologue, then return 0. */
|
||
|
||
static CORE_ADDR
|
||
alpha_mdebug_after_prologue (CORE_ADDR pc, struct mdebug_extra_func_info *proc_desc)
|
||
{
|
||
if (proc_desc)
|
||
{
|
||
/* If function is frameless, then we need to do it the hard way. I
|
||
strongly suspect that frameless always means prologueless... */
|
||
if (PROC_FRAME_REG (proc_desc) == ALPHA_SP_REGNUM
|
||
&& PROC_FRAME_OFFSET (proc_desc) == 0)
|
||
return 0;
|
||
}
|
||
|
||
return alpha_after_prologue (pc);
|
||
}
|
||
|
||
/* Return non-zero if we *might* be in a function prologue. Return zero
|
||
if we are definitively *not* in a function prologue. */
|
||
|
||
static int
|
||
alpha_mdebug_in_prologue (CORE_ADDR pc, struct mdebug_extra_func_info *proc_desc)
|
||
{
|
||
CORE_ADDR after_prologue_pc = alpha_mdebug_after_prologue (pc, proc_desc);
|
||
return (after_prologue_pc == 0 || pc < after_prologue_pc);
|
||
}
|
||
|
||
|
||
/* Frame unwinder that reads mdebug PDRs. */
|
||
|
||
struct alpha_mdebug_unwind_cache
|
||
{
|
||
struct mdebug_extra_func_info *proc_desc;
|
||
CORE_ADDR vfp;
|
||
struct trad_frame_saved_reg *saved_regs;
|
||
};
|
||
|
||
/* Extract all of the information about the frame from PROC_DESC
|
||
and store the resulting register save locations in the structure. */
|
||
|
||
static struct alpha_mdebug_unwind_cache *
|
||
alpha_mdebug_frame_unwind_cache (struct frame_info *this_frame,
|
||
void **this_prologue_cache)
|
||
{
|
||
struct alpha_mdebug_unwind_cache *info;
|
||
struct mdebug_extra_func_info *proc_desc;
|
||
ULONGEST vfp;
|
||
CORE_ADDR pc, reg_position;
|
||
unsigned long mask;
|
||
int ireg, returnreg;
|
||
|
||
if (*this_prologue_cache)
|
||
return *this_prologue_cache;
|
||
|
||
info = FRAME_OBSTACK_ZALLOC (struct alpha_mdebug_unwind_cache);
|
||
*this_prologue_cache = info;
|
||
pc = get_frame_pc (this_frame);
|
||
|
||
/* ??? We don't seem to be able to cache the lookup of the PDR
|
||
from alpha_mdebug_frame_p. It'd be nice if we could change
|
||
the arguments to that function. Oh well. */
|
||
proc_desc = find_proc_desc (pc);
|
||
info->proc_desc = proc_desc;
|
||
gdb_assert (proc_desc != NULL);
|
||
|
||
info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
|
||
|
||
/* The VFP of the frame is at FRAME_REG+FRAME_OFFSET. */
|
||
vfp = get_frame_register_unsigned (this_frame, PROC_FRAME_REG (proc_desc));
|
||
vfp += PROC_FRAME_OFFSET (info->proc_desc);
|
||
info->vfp = vfp;
|
||
|
||
/* Fill in the offsets for the registers which gen_mask says were saved. */
|
||
|
||
reg_position = vfp + PROC_REG_OFFSET (proc_desc);
|
||
mask = PROC_REG_MASK (proc_desc);
|
||
returnreg = PROC_PC_REG (proc_desc);
|
||
|
||
/* Note that RA is always saved first, regardless of its actual
|
||
register number. */
|
||
if (mask & (1 << returnreg))
|
||
{
|
||
/* Clear bit for RA so we don't save it again later. */
|
||
mask &= ~(1 << returnreg);
|
||
|
||
info->saved_regs[returnreg].addr = reg_position;
|
||
reg_position += 8;
|
||
}
|
||
|
||
for (ireg = 0; ireg <= 31; ++ireg)
|
||
if (mask & (1 << ireg))
|
||
{
|
||
info->saved_regs[ireg].addr = reg_position;
|
||
reg_position += 8;
|
||
}
|
||
|
||
reg_position = vfp + PROC_FREG_OFFSET (proc_desc);
|
||
mask = PROC_FREG_MASK (proc_desc);
|
||
|
||
for (ireg = 0; ireg <= 31; ++ireg)
|
||
if (mask & (1 << ireg))
|
||
{
|
||
info->saved_regs[ALPHA_FP0_REGNUM + ireg].addr = reg_position;
|
||
reg_position += 8;
|
||
}
|
||
|
||
/* The stack pointer of the previous frame is computed by popping
|
||
the current stack frame. */
|
||
if (!trad_frame_addr_p (info->saved_regs, ALPHA_SP_REGNUM))
|
||
trad_frame_set_value (info->saved_regs, ALPHA_SP_REGNUM, vfp);
|
||
|
||
return info;
|
||
}
|
||
|
||
/* 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
|
||
alpha_mdebug_frame_this_id (struct frame_info *this_frame,
|
||
void **this_prologue_cache,
|
||
struct frame_id *this_id)
|
||
{
|
||
struct alpha_mdebug_unwind_cache *info
|
||
= alpha_mdebug_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
|
||
*this_id = frame_id_build (info->vfp, get_frame_func (this_frame));
|
||
}
|
||
|
||
/* Retrieve the value of REGNUM in FRAME. Don't give up! */
|
||
|
||
static struct value *
|
||
alpha_mdebug_frame_prev_register (struct frame_info *this_frame,
|
||
void **this_prologue_cache, int regnum)
|
||
{
|
||
struct alpha_mdebug_unwind_cache *info
|
||
= alpha_mdebug_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
|
||
/* The PC of the previous frame is stored in the link register of
|
||
the current frame. Frob regnum so that we pull the value from
|
||
the correct place. */
|
||
if (regnum == ALPHA_PC_REGNUM)
|
||
regnum = PROC_PC_REG (info->proc_desc);
|
||
|
||
return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
|
||
}
|
||
|
||
static int
|
||
alpha_mdebug_frame_sniffer (const struct frame_unwind *self,
|
||
struct frame_info *this_frame,
|
||
void **this_cache)
|
||
{
|
||
CORE_ADDR pc = get_frame_address_in_block (this_frame);
|
||
struct mdebug_extra_func_info *proc_desc;
|
||
|
||
/* If this PC does not map to a PDR, then clearly this isn't an
|
||
mdebug frame. */
|
||
proc_desc = find_proc_desc (pc);
|
||
if (proc_desc == NULL)
|
||
return 0;
|
||
|
||
/* If we're in the prologue, the PDR for this frame is not yet valid.
|
||
Say no here and we'll fall back on the heuristic unwinder. */
|
||
if (alpha_mdebug_in_prologue (pc, proc_desc))
|
||
return 0;
|
||
|
||
return 1;
|
||
}
|
||
|
||
static const struct frame_unwind alpha_mdebug_frame_unwind = {
|
||
NORMAL_FRAME,
|
||
alpha_mdebug_frame_this_id,
|
||
alpha_mdebug_frame_prev_register,
|
||
NULL,
|
||
alpha_mdebug_frame_sniffer
|
||
};
|
||
|
||
static CORE_ADDR
|
||
alpha_mdebug_frame_base_address (struct frame_info *this_frame,
|
||
void **this_prologue_cache)
|
||
{
|
||
struct alpha_mdebug_unwind_cache *info
|
||
= alpha_mdebug_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
|
||
return info->vfp;
|
||
}
|
||
|
||
static CORE_ADDR
|
||
alpha_mdebug_frame_locals_address (struct frame_info *this_frame,
|
||
void **this_prologue_cache)
|
||
{
|
||
struct alpha_mdebug_unwind_cache *info
|
||
= alpha_mdebug_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
|
||
return info->vfp - PROC_LOCALOFF (info->proc_desc);
|
||
}
|
||
|
||
static CORE_ADDR
|
||
alpha_mdebug_frame_args_address (struct frame_info *this_frame,
|
||
void **this_prologue_cache)
|
||
{
|
||
struct alpha_mdebug_unwind_cache *info
|
||
= alpha_mdebug_frame_unwind_cache (this_frame, this_prologue_cache);
|
||
|
||
return info->vfp - ALPHA_NUM_ARG_REGS * 8;
|
||
}
|
||
|
||
static const struct frame_base alpha_mdebug_frame_base = {
|
||
&alpha_mdebug_frame_unwind,
|
||
alpha_mdebug_frame_base_address,
|
||
alpha_mdebug_frame_locals_address,
|
||
alpha_mdebug_frame_args_address
|
||
};
|
||
|
||
static const struct frame_base *
|
||
alpha_mdebug_frame_base_sniffer (struct frame_info *this_frame)
|
||
{
|
||
CORE_ADDR pc = get_frame_address_in_block (this_frame);
|
||
struct mdebug_extra_func_info *proc_desc;
|
||
|
||
/* If this PC does not map to a PDR, then clearly this isn't an
|
||
mdebug frame. */
|
||
proc_desc = find_proc_desc (pc);
|
||
if (proc_desc == NULL)
|
||
return NULL;
|
||
|
||
return &alpha_mdebug_frame_base;
|
||
}
|
||
|
||
|
||
void
|
||
alpha_mdebug_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
||
|
||
frame_unwind_append_unwinder (gdbarch, &alpha_mdebug_frame_unwind);
|
||
frame_base_append_sniffer (gdbarch, alpha_mdebug_frame_base_sniffer);
|
||
}
|