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authorjakub <jakub@138bc75d-0d04-0410-961f-82ee72b054a4>2009-04-04 11:41:16 +0000
committerjakub <jakub@138bc75d-0d04-0410-961f-82ee72b054a4>2009-04-04 11:41:16 +0000
commitd02454a0d2e61b542b55db4f65bb6763d714a922 (patch)
tree1ec79fced82ed21a4a99ea0de1bfbb49408cc202 /gcc/unwind-dw2.c
parent19f6bf8d98e213f2da574c5e090fa959b4177fc0 (diff)
downloadgcc-d02454a0d2e61b542b55db4f65bb6763d714a922.tar.gz
* unwind-dw2.h (_Unwind_FrameState): Add REG_UNDEFINED enum value.
* unwind-dw2.c (execute_cfa_program): Set how to REG_UNDEFINED instead of REG_UNSAVED for DW_CFA_undefined. (uw_update_context_1): Handle REG_UNDEFINED the same as REG_UNSAVED. (uw_update_context): If RA column is REG_UNDEFINED, mark it as outermost frame. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@145535 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/unwind-dw2.c')
-rw-r--r--gcc/unwind-dw2.c29
1 files changed, 23 insertions, 6 deletions
diff --git a/gcc/unwind-dw2.c b/gcc/unwind-dw2.c
index 3845467e44c..6df1ffa55a6 100644
--- a/gcc/unwind-dw2.c
+++ b/gcc/unwind-dw2.c
@@ -1,6 +1,6 @@
/* DWARF2 exception handling and frame unwind runtime interface routines.
Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
- 2008 Free Software Foundation, Inc.
+ 2008, 2009 Free Software Foundation, Inc.
This file is part of GCC.
@@ -943,12 +943,16 @@ execute_cfa_program (const unsigned char *insn_ptr,
fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNSAVED;
break;
- case DW_CFA_undefined:
case DW_CFA_same_value:
insn_ptr = read_uleb128 (insn_ptr, &reg);
fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNSAVED;
break;
+ case DW_CFA_undefined:
+ insn_ptr = read_uleb128 (insn_ptr, &reg);
+ fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNDEFINED;
+ break;
+
case DW_CFA_nop:
break;
@@ -1319,6 +1323,7 @@ uw_update_context_1 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
switch (fs->regs.reg[i].how)
{
case REG_UNSAVED:
+ case REG_UNDEFINED:
break;
case REG_SAVED_OFFSET:
@@ -1387,10 +1392,22 @@ uw_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs)
{
uw_update_context_1 (context, fs);
- /* Compute the return address now, since the return address column
- can change from frame to frame. */
- context->ra = __builtin_extract_return_addr
- (_Unwind_GetPtr (context, fs->retaddr_column));
+ /* In general this unwinder doesn't make any distinction between
+ undefined and same_value rule. Call-saved registers are assumed
+ to have same_value rule by default and explicit undefined
+ rule is handled like same_value. The only exception is
+ DW_CFA_undefined on retaddr_column which is supposed to
+ mark outermost frame in DWARF 3. */
+ if (fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN (fs->retaddr_column)].how
+ == REG_UNDEFINED)
+ /* uw_frame_state_for uses context->ra == 0 check to find outermost
+ stack frame. */
+ context->ra = 0;
+ else
+ /* Compute the return address now, since the return address column
+ can change from frame to frame. */
+ context->ra = __builtin_extract_return_addr
+ (_Unwind_GetPtr (context, fs->retaddr_column));
}
static void