re PR other/26208 (Serious problem with unwinding through signal frames)

	PR other/26208
	* unwind-dw2.c (struct _Unwind_Context): Add signal_frame field.
	(extract_cie_info): Handle S flag in augmentation string.
	(execute_cfa_program): If context->signal_frame, execute also
	fs->pc == context->ra instructions.
	(uw_frame_state_for): If context->signal_frame, don't subtract one
	from context->ra to find FDE.
	(uw_update_context_1): Set context->signal_frame to
	fs->signal_frame.
	(_Unwind_GetIPInfo): New function.
	* unwind-dw2.h (_Unwind_FrameState): Add signal_frame field.
	* unwind-c.c (PERSONALITY_FUNCTION): Use _Unwind_GetIPInfo instead
	of _Unwind_GetIP.
	* unwind-sjlj.c (_Unwind_GetIPInfo): New function.
	* unwind-generic.h (_Unwind_GetIPInfo): New prototype.
	* unwind-compat.c (_Unwind_GetIPInfo): New function.
	* libgcc-std.ver (_Unwind_GetIPInfo): Export @@GCC_4.2.0.
	* config/ia64/unwind-ia64.c (_Unwind_GetIPInfo): New function.
	* config/arm/unwind-arm.h (_Unwind_GetIPInfo): Define.
	* config/i386/linux-unwind.h (x86_fallback_frame_state,
	x86_64_fallback_frame_state): Set fs->signal_frame.
	* config/rs6000/linux-unwind.h (ppc_fallback_frame_state): Likewise.
	(MD_FROB_UPDATE_CONTEXT): Define unconditionally.
	(frob_update_context): Likewise.  Workaround missing S flag in
	Linux 2.6.12 - 2.6.16 kernel vDSOs.
	* config/s390/linux-unwind.h (s390_fallback_frame_state): Likewise.
	Remove the psw_addr + 1 hack.
libjava/
	* exception.cc (PERSONALITY_FUNCTION): Use _Unwind_GetIPInfo instead
	of _Unwind_GetIP.
	* include/i386-signal.h (MAKE_THROW_FRAME): Change into empty macro.
	(HANDLE_DIVIDE_OVERFLOW): Don't adjust _res->eip if falling through
	to throw.
	* include/x86_64-signal.h (MAKE_THROW_FRAME): Change into empty
	macro.
	* include/powerpc-signal.h (MAKE_THROW_FRAME): Change into empty
	macro.
libstdc++-v3/
	* libsupc++/eh_personality.cc (PERSONALITY_FUNCTION): Use
	_Unwind_GetIPInfo instead of _Unwind_GetIP.

From-SVN: r111488

1 files changed, 27 insertions, 4 deletions

diff --git a/gcc/unwind-dw2.c b/gcc/unwind-dw2.c
index 930f02f3799..8707391a86b 100644
--- a/gcc/unwind-dw2.c
+++ b/gcc/unwind-dw2.c
@@ -1,5 +1,5 @@
 /* DWARF2 exception handling and frame unwind runtime interface routines.
-   Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
+   Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
    Free Software Foundation, Inc.
 
    This file is part of GCC.
@@ -71,6 +71,7 @@ struct _Unwind_Context
   void *lsda;
   struct dwarf_eh_bases bases;
   _Unwind_Word args_size;
+  char signal_frame;
 };
 
 /* Byte size of every register managed by these routines.  */
@@ -207,6 +208,16 @@ _Unwind_GetIP (struct _Unwind_Context *context)
   return (_Unwind_Ptr) context->ra;
 }
 
+/* Retrieve the return address and flag whether that IP is before
+   or after first not yet fully executed instruction.  */
+
+inline _Unwind_Ptr
+_Unwind_GetIPInfo (struct _Unwind_Context *context, int *ip_before_insn)
+{
+  *ip_before_insn = context->signal_frame != 0;
+  return (_Unwind_Ptr) context->ra;
+}
+
 /* Overwrite the return address for CONTEXT with VAL.  */
 
 inline void
@@ -327,6 +338,13 @@ extract_cie_info (const struct dwarf_cie *cie, struct _Unwind_Context *context,
 	  aug += 1;
 	}
 
+      /* "S" indicates a signal frame.  */
+      else if (aug[0] == 'S')
+	{
+	  fs->signal_frame = 1;
+	  aug += 1;
+	}
+
       /* Otherwise we have an unknown augmentation string.
 	 Bail unless we saw a 'z' prefix.  */
       else
@@ -761,8 +779,10 @@ execute_cfa_program (const unsigned char *insn_ptr,
      a different stack configuration that we are not interested in.  We
      assume that the call itself is unwind info-neutral; if not, or if
      there are delay instructions that adjust the stack, these must be
-     reflected at the point immediately before the call insn.  */
-  while (insn_ptr < insn_end && fs->pc < context->ra)
+     reflected at the point immediately before the call insn.
+     In signal frames, return address is after last completed instruction,
+     so we add 1 to return address to make the comparison <=.  */
+  while (insn_ptr < insn_end && fs->pc < context->ra + context->signal_frame)
     {
       unsigned char insn = *insn_ptr++;
       _Unwind_Word reg, utmp;
@@ -974,7 +994,8 @@ uw_frame_state_for (struct _Unwind_Context *context, _Unwind_FrameState *fs)
   if (context->ra == 0)
     return _URC_END_OF_STACK;
 
-  fde = _Unwind_Find_FDE (context->ra - 1, &context->bases);
+  fde = _Unwind_Find_FDE (context->ra + context->signal_frame - 1,
+			  &context->bases);
   if (fde == NULL)
     {
 #ifdef MD_FALLBACK_FRAME_STATE_FOR
@@ -1192,6 +1213,8 @@ uw_update_context_1 (struct _Unwind_Context *context, _Unwind_FrameState *fs)
 	break;
       }
 
+  context->signal_frame = fs->signal_frame;
+
 #ifdef MD_FROB_UPDATE_CONTEXT
   MD_FROB_UPDATE_CONTEXT (context, fs);
 #endif