static struct mdebug_extra_func_info *
non_heuristic_proc_desc (CORE_ADDR pc, CORE_ADDR *addrptr)
{
CORE_ADDR startaddr;
struct mdebug_extra_func_info *proc_desc;
struct block *b = block_for_pc (pc);
struct symbol *sym;
struct obj_section *sec;
struct mips_objfile_private *priv;
find_pc_partial_function (pc, NULL, &startaddr, NULL);
if (addrptr)
*addrptr = startaddr;
priv = NULL;
sec = find_pc_section (pc);
if (sec != NULL)
{
priv = (struct mips_objfile_private *) objfile_data (sec->objfile, mips_pdr_data);
/* Search the ".pdr" section generated by GAS. This includes most of
the information normally found in ECOFF PDRs. */
the_bfd = sec->objfile->obfd;
if (priv == NULL
&& (the_bfd->format == bfd_object
&& bfd_get_flavour (the_bfd) == bfd_target_elf_flavour
&& elf_elfheader (the_bfd)->e_ident[EI_CLASS] == ELFCLASS64))
{
/* Right now GAS only outputs the address as a four-byte sequence.
This means that we should not bother with this method on 64-bit
targets (until that is fixed). */
priv = obstack_alloc (&sec->objfile->objfile_obstack,
sizeof (struct mips_objfile_private));
priv->size = 0;
set_objfile_data (sec->objfile, mips_pdr_data, priv);
}
else if (priv == NULL)
{
asection *bfdsec;
priv = obstack_alloc (&sec->objfile->objfile_obstack,
sizeof (struct mips_objfile_private));
bfdsec = bfd_get_section_by_name (sec->objfile->obfd, ".pdr");
if (bfdsec != NULL)
{
priv->size = bfd_section_size (sec->objfile->obfd, bfdsec);
priv->contents = obstack_alloc (&sec->objfile->objfile_obstack,
priv->size);
bfd_get_section_contents (sec->objfile->obfd, bfdsec,
priv->contents, 0, priv->size);
/* In general, the .pdr section is sorted. However, in the
presence of multiple code sections (and other corner cases)
it can become unsorted. Sort it so that we can use a faster
binary search. */
qsort (priv->contents, priv->size / 32, 32,
compare_pdr_entries);
}
else
priv->size = 0;
set_objfile_data (sec->objfile, mips_pdr_data, priv);
}
the_bfd = NULL;
if (priv->size != 0)
{
int low, mid, high;
char *ptr;
CORE_ADDR pdr_pc;
low = 0;
high = priv->size / 32;
/* We've found a .pdr section describing this objfile. We want to
find the entry which describes this code address. The .pdr
information is not very descriptive; we have only a function
start address. We have to look for the closest entry, because
the local symbol at the beginning of this function may have
been stripped - so if we ask the symbol table for the start
address we may get a preceding global function. */
/* First, find the last .pdr entry starting at or before PC. */
do
{
mid = (low + high) / 2;
ptr = priv->contents + mid * 32;
pdr_pc = bfd_get_signed_32 (sec->objfile->obfd, ptr);
pdr_pc += ANOFFSET (sec->objfile->section_offsets,
SECT_OFF_TEXT (sec->objfile));
if (pdr_pc > pc)
high = mid;
else
low = mid + 1;
}
while (low != high);
/* Both low and high point one past the PDR of interest. If
both are zero, that means this PC is before any region
covered by a PDR, i.e. pdr_pc for the first PDR entry is
greater than PC. */
if (low > 0)
{
ptr = priv->contents + (low - 1) * 32;
pdr_pc = bfd_get_signed_32 (sec->objfile->obfd, ptr);
pdr_pc += ANOFFSET (sec->objfile->section_offsets,
SECT_OFF_TEXT (sec->objfile));
}
/* We don't have a range, so we have no way to know for sure
whether we're in the correct PDR or a PDR for a preceding
function and the current function was a stripped local
symbol. But if the PDR's PC is at least as great as the
best guess from the symbol table, assume that it does cover
the right area; if a .pdr section is present at all then
nearly every function will have an entry. The biggest exception
will be the dynamic linker stubs; conveniently these are
placed before .text instead of after. */
if (pc >= pdr_pc && pdr_pc >= startaddr)
{
struct symbol *sym = find_pc_function (pc);
if (addrptr)
*addrptr = pdr_pc;
/* Fill in what we need of the proc_desc. */
proc_desc = (struct mdebug_extra_func_info *)
obstack_alloc (&sec->objfile->objfile_obstack,
sizeof (struct mdebug_extra_func_info));
PROC_LOW_ADDR (proc_desc) = pdr_pc;
PROC_FRAME_OFFSET (proc_desc)
= bfd_get_signed_32 (sec->objfile->obfd, ptr + 20);
PROC_FRAME_REG (proc_desc) = bfd_get_32 (sec->objfile->obfd,
ptr + 24);
PROC_REG_MASK (proc_desc) = bfd_get_32 (sec->objfile->obfd,
ptr + 4);
PROC_FREG_MASK (proc_desc) = bfd_get_32 (sec->objfile->obfd,
ptr + 12);
PROC_REG_OFFSET (proc_desc)
= bfd_get_signed_32 (sec->objfile->obfd, ptr + 8);
PROC_FREG_OFFSET (proc_desc)
= bfd_get_signed_32 (sec->objfile->obfd, ptr + 16);
PROC_PC_REG (proc_desc) = bfd_get_32 (sec->objfile->obfd,
ptr + 28);
proc_desc->pdr.isym = (long) sym;
return proc_desc;
}
}
}
if (b == NULL)
return 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. */
return NULL;
}
sym = lookup_symbol (MDEBUG_EFI_SYMBOL_NAME, b, LABEL_DOMAIN, 0);
/* If we never found a PDR for this function in symbol reading, then
examine prologues to find the information. */
if (sym)
{
proc_desc = (struct mdebug_extra_func_info *) SYMBOL_VALUE (sym);
if (PROC_FRAME_REG (proc_desc) == -1)
return NULL;
else
return proc_desc;
}
else
return NULL;
}
static alpha_extra_func_info_t
heuristic_proc_desc (CORE_ADDR start_pc,
CORE_ADDR limit_pc,
struct frame_info *next_frame,
struct frame_saved_regs *saved_regs_p)
{
CORE_ADDR sp = read_next_frame_reg (next_frame, SP_REGNUM);
CORE_ADDR cur_pc;
int frame_size;
int has_frame_reg = 0;
unsigned long reg_mask = 0;
int pcreg = -1;
if (start_pc == 0)
return 0;
memset (&temp_proc_desc, '\0', sizeof (temp_proc_desc));
if (saved_regs_p != 0)
memset (saved_regs_p, '\0', sizeof (struct frame_saved_regs));
PROC_LOW_ADDR (&temp_proc_desc) = start_pc;
if (start_pc + 200 < limit_pc)
limit_pc = start_pc + 200;
frame_size = 0;
for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += 4)
{
unsigned int word;
int status;
status = read_memory_safe4 (cur_pc, &word);
if (status)
return 0;
if ((word & 0xffff0000) == 0x23de0000) /* lda $sp,n($sp) */
{
if (word & 0x8000)
frame_size += (-word) & 0xffff;
else
/* Exit loop if a positive stack adjustment is found, which
usually means that the stack cleanup code in the function
epilogue is reached. */
break;
}
else if ((word & 0xfc1f0000) == 0xb41e0000 /* stq reg,n($sp) */
&& (word & 0xffff0000) != 0xb7fe0000) /* reg != $zero */
{
int reg = (word & 0x03e00000) >> 21;
reg_mask |= 1 << reg;
if (saved_regs_p != 0)
saved_regs_p->regs[reg] = sp + (short) word;
/* Starting with OSF/1-3.2C, the system libraries are shipped
without local symbols, but they still contain procedure
descriptors without a symbol reference. GDB is currently
unable to find these procedure descriptors and uses
heuristic_proc_desc instead.
As some low level compiler support routines (__div*, __add*)
use a non-standard return address register, we have to
add some heuristics to determine the return address register,
or stepping over these routines will fail.
Usually the return address register is the first register
saved on the stack, but assembler optimization might
rearrange the register saves.
So we recognize only a few registers (t7, t9, ra) within
the procedure prologue as valid return address registers.
If we encounter a return instruction, we extract the
the return address register from it.
FIXME: Rewriting GDB to access the procedure descriptors,
e.g. via the minimal symbol table, might obviate this hack. */
if (pcreg == -1
&& cur_pc < (start_pc + 80)
&& (reg == T7_REGNUM || reg == T9_REGNUM || reg == RA_REGNUM))
pcreg = reg;
}
else if ((word & 0xffe0ffff) == 0x6be08001) /* ret zero,reg,1 */
