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Diffstat (limited to 'gdb/rs6000-tdep.c')
-rw-r--r--gdb/rs6000-tdep.c105
1 files changed, 31 insertions, 74 deletions
diff --git a/gdb/rs6000-tdep.c b/gdb/rs6000-tdep.c
index 25fa550..cc2f074 100644
--- a/gdb/rs6000-tdep.c
+++ b/gdb/rs6000-tdep.c
@@ -482,7 +482,29 @@ static CORE_ADDR
rs6000_skip_prologue (CORE_ADDR pc)
{
struct rs6000_framedata frame;
- pc = skip_prologue (pc, 0, &frame);
+ CORE_ADDR limit_pc, func_addr;
+
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+ if (find_pc_partial_function (pc, NULL, &func_addr, NULL))
+ {
+ CORE_ADDR post_prologue_pc = skip_prologue_using_sal (func_addr);
+ if (post_prologue_pc != 0)
+ return max (pc, post_prologue_pc);
+ }
+
+ /* Can't determine prologue from the symbol table, need to examine
+ instructions. */
+
+ /* Find an upper limit on the function prologue using the debug
+ information. If the debug information could not be used to provide
+ that bound, then use an arbitrary large number as the upper bound. */
+ limit_pc = skip_prologue_using_sal (pc);
+ if (limit_pc == 0)
+ limit_pc = pc + 100; /* Magic. */
+
+ pc = skip_prologue (pc, limit_pc, &frame);
return pc;
}
@@ -565,7 +587,7 @@ rs6000_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
{
if (!safe_frame_unwind_memory (curfrm, scan_pc, insn_buf, PPC_INSN_SIZE))
return 0;
- insn = extract_signed_integer (insn_buf, PPC_INSN_SIZE);
+ insn = extract_unsigned_integer (insn_buf, PPC_INSN_SIZE);
if (insn == 0x4e800020)
break;
if (insn_changes_sp_or_jumps (insn))
@@ -580,7 +602,7 @@ rs6000_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
{
if (!safe_frame_unwind_memory (curfrm, scan_pc, insn_buf, PPC_INSN_SIZE))
return 0;
- insn = extract_signed_integer (insn_buf, PPC_INSN_SIZE);
+ insn = extract_unsigned_integer (insn_buf, PPC_INSN_SIZE);
if (insn_changes_sp_or_jumps (insn))
return 1;
}
@@ -775,57 +797,6 @@ rs6000_software_single_step (enum target_signal signal,
of the prologue is expensive. */
static int max_skip_non_prologue_insns = 10;
-/* Given PC representing the starting address of a function, and
- LIM_PC which is the (sloppy) limit to which to scan when looking
- for a prologue, attempt to further refine this limit by using
- the line data in the symbol table. If successful, a better guess
- on where the prologue ends is returned, otherwise the previous
- value of lim_pc is returned. */
-
-/* FIXME: cagney/2004-02-14: This function and logic have largely been
- superseded by skip_prologue_using_sal. */
-
-static CORE_ADDR
-refine_prologue_limit (CORE_ADDR pc, CORE_ADDR lim_pc)
-{
- struct symtab_and_line prologue_sal;
-
- prologue_sal = find_pc_line (pc, 0);
- if (prologue_sal.line != 0)
- {
- int i;
- CORE_ADDR addr = prologue_sal.end;
-
- /* Handle the case in which compiler's optimizer/scheduler
- has moved instructions into the prologue. We scan ahead
- in the function looking for address ranges whose corresponding
- line number is less than or equal to the first one that we
- found for the function. (It can be less than when the
- scheduler puts a body instruction before the first prologue
- instruction.) */
- for (i = 2 * max_skip_non_prologue_insns;
- i > 0 && (lim_pc == 0 || addr < lim_pc);
- i--)
- {
- struct symtab_and_line sal;
-
- sal = find_pc_line (addr, 0);
- if (sal.line == 0)
- break;
- if (sal.line <= prologue_sal.line
- && sal.symtab == prologue_sal.symtab)
- {
- prologue_sal = sal;
- }
- addr = sal.end;
- }
-
- if (lim_pc == 0 || prologue_sal.end < lim_pc)
- lim_pc = prologue_sal.end;
- }
- return lim_pc;
-}
-
/* Return nonzero if the given instruction OP can be part of the prologue
of a function and saves a parameter on the stack. FRAMEP should be
set if one of the previous instructions in the function has set the
@@ -945,21 +916,6 @@ skip_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct rs6000_framedata *fdata)
int r0_contains_arg = 0;
const struct bfd_arch_info *arch_info = gdbarch_bfd_arch_info (current_gdbarch);
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
-
- /* Attempt to find the end of the prologue when no limit is specified.
- Note that refine_prologue_limit() has been written so that it may
- be used to "refine" the limits of non-zero PC values too, but this
- is only safe if we 1) trust the line information provided by the
- compiler and 2) iterate enough to actually find the end of the
- prologue.
-
- It may become a good idea at some point (for both performance and
- accuracy) to unconditionally call refine_prologue_limit(). But,
- until we can make a clear determination that this is beneficial,
- we'll play it safe and only use it to obtain a limit when none
- has been specified. */
- if (lim_pc == 0)
- lim_pc = refine_prologue_limit (pc, lim_pc);
memset (fdata, 0, sizeof (struct rs6000_framedata));
fdata->saved_gpr = -1;
@@ -980,7 +936,7 @@ skip_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct rs6000_framedata *fdata)
last_prologue_pc = pc;
/* Stop scanning if we've hit the limit. */
- if (lim_pc != 0 && pc >= lim_pc)
+ if (pc >= lim_pc)
break;
prev_insn_was_prologue_insn = 1;
@@ -988,7 +944,7 @@ skip_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct rs6000_framedata *fdata)
/* Fetch the instruction and convert it to an integer. */
if (target_read_memory (pc, buf, 4))
break;
- op = extract_signed_integer (buf, 4);
+ op = extract_unsigned_integer (buf, 4);
if ((op & 0xfc1fffff) == 0x7c0802a6)
{ /* mflr Rx */
@@ -1221,9 +1177,11 @@ skip_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct rs6000_framedata *fdata)
offset = fdata->offset;
continue;
}
- /* Load up minimal toc pointer */
+ /* Load up minimal toc pointer. Do not treat an epilogue restore
+ of r31 as a minimal TOC load. */
else if (((op >> 22) == 0x20f || /* l r31,... or l r30,... */
(op >> 22) == 0x3af) /* ld r31,... or ld r30,... */
+ && !framep
&& !minimal_toc_loaded)
{
minimal_toc_loaded = 1;
@@ -1446,8 +1404,7 @@ skip_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct rs6000_framedata *fdata)
Handle optimizer code motions into the prologue by continuing
the search if we have no valid frame yet or if the return
address is not yet saved in the frame. */
- if (fdata->frameless == 0
- && (lr_reg == -1 || fdata->nosavedpc == 0))
+ if (fdata->frameless == 0 && fdata->nosavedpc == 0)
break;
if (op == 0x4e800020 /* blr */
generated by cgit v1.1 at 2024-12-28 17:07:36 +0000