/* Frame unwinder for frames with DWARF Call Frame Information.
- Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009
+ Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
Contributed by Mark Kettenis.
static CORE_ADDR
execute_stack_op (gdb_byte *exp, ULONGEST len, int addr_size,
- struct frame_info *this_frame, CORE_ADDR initial)
+ struct frame_info *this_frame, CORE_ADDR initial,
+ int initial_in_stack_memory)
{
struct dwarf_expr_context *ctx;
CORE_ADDR result;
ctx->get_frame_cfa = no_get_frame_cfa;
ctx->get_tls_address = no_get_tls_address;
- dwarf_expr_push (ctx, initial);
+ dwarf_expr_push (ctx, initial, initial_in_stack_memory);
dwarf_expr_eval (ctx, exp, len);
result = dwarf_expr_fetch (ctx, 0);
- if (ctx->in_reg)
+ if (ctx->location == DWARF_VALUE_REGISTER)
result = read_reg (this_frame, result);
+ else if (ctx->location != DWARF_VALUE_MEMORY)
+ {
+ /* This is actually invalid DWARF, but if we ever do run across
+ it somehow, we might as well support it. So, instead, report
+ it as unimplemented. */
+ error (_("Not implemented: computing unwound register using explicit value operator"));
+ }
do_cleanups (old_chain);
case CFA_EXP:
cache->cfa =
execute_stack_op (fs->regs.cfa_exp, fs->regs.cfa_exp_len,
- cache->addr_size, this_frame, 0);
+ cache->addr_size, this_frame, 0, 0);
break;
default:
case DWARF2_FRAME_REG_SAVED_EXP:
addr = execute_stack_op (cache->reg[regnum].loc.exp,
cache->reg[regnum].exp_len,
- cache->addr_size, this_frame, cache->cfa);
+ cache->addr_size, this_frame, cache->cfa, 1);
return frame_unwind_got_memory (this_frame, regnum, addr);
case DWARF2_FRAME_REG_SAVED_VAL_OFFSET:
case DWARF2_FRAME_REG_SAVED_VAL_EXP:
addr = execute_stack_op (cache->reg[regnum].loc.exp,
cache->reg[regnum].exp_len,
- cache->addr_size, this_frame, cache->cfa);
+ cache->addr_size, this_frame, cache->cfa, 1);
return frame_unwind_got_constant (this_frame, regnum, addr);
case DWARF2_FRAME_REG_UNSPECIFIED:
{
struct dwarf2_cie **p_cie;
+ /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to
+ bsearch be non-NULL. */
+ if (cie_table->entries == NULL)
+ {
+ gdb_assert (cie_table->num_entries == 0);
+ return NULL;
+ }
+
p_cie = bsearch (&cie_pointer, cie_table->entries, cie_table->num_entries,
sizeof (cie_table->entries[0]), bsearch_cie_cmp);
if (p_cie != NULL)
if (fde_table.num_entries != 0)
{
struct dwarf2_fde_table *fde_table2;
- int i, j;
+ struct dwarf2_fde *fde_prev = NULL;
+ struct dwarf2_fde *first_non_zero_fde = NULL;
+ int i;
/* Prepare FDE table for lookups. */
qsort (fde_table.entries, fde_table.num_entries,
/* Copy fde_table to obstack: it is needed at runtime. */
fde_table2 = (struct dwarf2_fde_table *)
obstack_alloc (&objfile->objfile_obstack, sizeof (*fde_table2));
+ fde_table2->num_entries = 0;
+
+ /* Check for leftovers from --gc-sections. The GNU linker sets
+ the relevant symbols to zero, but doesn't zero the FDE *end*
+ ranges because there's no relocation there. It's (offset,
+ length), not (start, end). On targets where address zero is
+ just another valid address this can be a problem, since the
+ FDEs appear to be non-empty in the output --- we could pick
+ out the wrong FDE. To work around this, when overlaps are
+ detected, we prefer FDEs that do not start at zero.
+
+ Start by finding the first FDE with non-zero start. Below
+ we'll discard all FDEs that start at zero and overlap this
+ one. */
+ for (i = 0; i < fde_table.num_entries; i++)
+ {
+ struct dwarf2_fde *fde = fde_table.entries[i];
- /* Since we'll be doing bsearch, squeeze out identical (except for
- eh_frame_p) fde entries so bsearch result is predictable. */
- for (i = 0, j = 0; j < fde_table.num_entries; ++i)
- {
- const int k = j;
-
- obstack_grow (&objfile->objfile_obstack, &fde_table.entries[j],
- sizeof (fde_table.entries[0]));
- while (++j < fde_table.num_entries
- && (fde_table.entries[k]->initial_location ==
- fde_table.entries[j]->initial_location))
- /* Skip. */;
- }
+ if (fde->initial_location != 0)
+ {
+ first_non_zero_fde = fde;
+ break;
+ }
+ }
+
+ /* Since we'll be doing bsearch, squeeze out identical (except
+ for eh_frame_p) fde entries so bsearch result is predictable.
+ Also discard leftovers from --gc-sections. */
+ for (i = 0; i < fde_table.num_entries; i++)
+ {
+ struct dwarf2_fde *fde = fde_table.entries[i];
+
+ if (fde->initial_location == 0
+ && first_non_zero_fde != NULL
+ && (first_non_zero_fde->initial_location
+ < fde->initial_location + fde->address_range))
+ continue;
+
+ if (fde_prev != NULL
+ && fde_prev->initial_location == fde->initial_location)
+ continue;
+
+ obstack_grow (&objfile->objfile_obstack, &fde_table.entries[i],
+ sizeof (fde_table.entries[0]));
+ ++fde_table2->num_entries;
+ fde_prev = fde;
+ }
fde_table2->entries = obstack_finish (&objfile->objfile_obstack);
- fde_table2->num_entries = i;
set_objfile_data (objfile, dwarf2_frame_objfile_data, fde_table2);
/* Discard the original fde_table. */
projects / deliverable / binutils-gdb.git / blobdiff