From: Randolph Chung <tausq@debian.org>
Date: Sat, 8 May 2004 03:45:44 +0000 (+0000)
Subject: 2004-05-07  Randolph Chung  <tausq@debian.org>
X-Git-Tag: gprof-pre-ansify-2004-05-26~215
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2f0e8c7afffc1b2915c1f5b13bdf6551be661d75;p=external%2Fbinutils.git

2004-05-07  Randolph Chung  <tausq@debian.org>

	* hppa-linux-tdep.c (hppa_linux_sigtramp_find_sigcontext): Pass in pc
	instead of sp, handle sigaltstack case.
	(hppa_linux_sigtramp_frame_unwind_cache): Adjust calls to
	hppa_linux_sigtramp_find_sigcontext, and set base to the frame of the
	signal handler and not that of the caller.
	(hppa_linux_sigtramp_unwind_sniffer): Adjust calls to
	hppa_linux_sigtramp_find_sigcontext.
---

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 6460705..1d297c8 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,15 @@
 2004-05-07  Randolph Chung  <tausq@debian.org>
 
+	* hppa-linux-tdep.c (hppa_linux_sigtramp_find_sigcontext): Pass in pc
+	instead of sp, handle sigaltstack case.
+	(hppa_linux_sigtramp_frame_unwind_cache): Adjust calls to 
+	hppa_linux_sigtramp_find_sigcontext, and set base to the frame of the
+	signal handler and not that of the caller.
+	(hppa_linux_sigtramp_unwind_sniffer): Adjust calls to
+	hppa_linux_sigtramp_find_sigcontext.
+
+2004-05-07  Randolph Chung  <tausq@debian.org>
+
 	* Makefile.in (ALLDEPFILES): Add hppa-linux-tdep.c and
 	hppa-linux-nat.c.
 	(hppa-linux-tdep.o, hppa-linux-nat.o): Define rules.
diff --git a/gdb/hppa-linux-tdep.c b/gdb/hppa-linux-tdep.c
index 8fae030..f57ef50 100644
--- a/gdb/hppa-linux-tdep.c
+++ b/gdb/hppa-linux-tdep.c
@@ -282,7 +282,7 @@ hppa_linux_skip_trampoline_code (CORE_ADDR pc)
    Note that with a 2.4 64-bit kernel, the signal context is not properly
    passed back to userspace so the unwind will not work correctly.  */
 static CORE_ADDR
-hppa_linux_sigtramp_find_sigcontext (CORE_ADDR sp)
+hppa_linux_sigtramp_find_sigcontext (CORE_ADDR pc)
 {
   unsigned int dummy[HPPA_MAX_INSN_PATTERN_LEN];
   int offs = 0;
@@ -291,6 +291,12 @@ hppa_linux_sigtramp_find_sigcontext (CORE_ADDR sp)
   static int pcoffs[] = { 0, 4*4, 5*4 };
   /* offsets to the rt_sigframe structure */
   static int sfoffs[] = { 4*4, 10*4, 10*4 };
+  CORE_ADDR sp;
+
+  /* Most of the time, this will be correct.  The one case when this will
+     fail is if the user defined an alternate stack, in which case the
+     beginning of the stack will not be align_down (pc, 64).  */
+  sp = align_down (pc, 64);
 
   /* rt_sigreturn trampoline:
      3419000x ldi 0, %r25 or ldi 1, %r25   (x = 0 or 2)
@@ -308,7 +314,20 @@ hppa_linux_sigtramp_find_sigcontext (CORE_ADDR sp)
     }
 
   if (offs == 0)
-    return 0;
+    {
+      if (insns_match_pattern (pc, hppa_sigtramp, dummy))
+	{
+	  /* sigaltstack case: we have no way of knowing which offset to 
+	     use in this case; default to new kernel handling. If this is
+	     wrong the unwinding will fail.  */
+	  try = 2;
+	  sp = pc - pcoffs[try];
+	}
+      else
+      {
+        return 0;
+      }
+    }
 
   /* sp + sfoffs[try] points to a struct rt_sigframe, which contains
      a struct siginfo and a struct ucontext.  struct ucontext contains
@@ -331,7 +350,7 @@ hppa_linux_sigtramp_frame_unwind_cache (struct frame_info *next_frame,
 {
   struct gdbarch *gdbarch = get_frame_arch (next_frame);
   struct hppa_linux_sigtramp_unwind_cache *info;
-  CORE_ADDR sp, pc, scptr;
+  CORE_ADDR pc, scptr;
   int i;
 
   if (*this_cache)
@@ -342,8 +361,7 @@ hppa_linux_sigtramp_frame_unwind_cache (struct frame_info *next_frame,
   info->saved_regs = trad_frame_alloc_saved_regs (next_frame);
 
   pc = frame_pc_unwind (next_frame);
-  sp = (pc & ~63);
-  scptr = hppa_linux_sigtramp_find_sigcontext (sp);
+  scptr = hppa_linux_sigtramp_find_sigcontext (pc);
 
   /* structure of struct sigcontext:
    
@@ -393,8 +411,7 @@ hppa_linux_sigtramp_frame_unwind_cache (struct frame_info *next_frame,
   info->saved_regs[HPPA_PCOQ_TAIL_REGNUM].addr = scptr;
   scptr += 4;
 
-  info->base = read_memory_unsigned_integer (
-		  info->saved_regs[HPPA_SP_REGNUM].addr, 4);
+  info->base = frame_unwind_register_unsigned (next_frame, HPPA_SP_REGNUM);
 
   return info;
 }
@@ -439,9 +456,8 @@ static const struct frame_unwind *
 hppa_linux_sigtramp_unwind_sniffer (struct frame_info *next_frame)
 {
   CORE_ADDR pc = frame_pc_unwind (next_frame);
-  CORE_ADDR sp = (pc & ~63);
 
-  if (hppa_linux_sigtramp_find_sigcontext (sp))
+  if (hppa_linux_sigtramp_find_sigcontext (pc))
     return &hppa_linux_sigtramp_frame_unwind;
 
   return NULL;