2004-06-07 Randolph Chung <tausq@debian.org>

	* hppa-tdep.c (hppa_frame_cache): Handle the cases when we start
	unwinding after sp has been saved to the stack but before the end
	of the prologue, and after the fp has been modified but before it has
	been saved to the stack.
	(hppa_frame_base_address, hppa_frame_base, hppa_frame_base_sniffer):
	Remove superfluous definitions.
	(hppa_gdbarch_init): Remove superfluous frame base sniffer.

2 files changed, 26 insertions, 43 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 35c043f..02be965 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,13 @@
+2004-06-07  Randolph Chung  <tausq@debian.org>
+
+	* hppa-tdep.c (hppa_frame_cache): Handle the cases when we start
+	unwinding after sp has been saved to the stack but before the end
+	of the prologue, and after the fp has been modified but before it has
+	been saved to the stack.
+	(hppa_frame_base_address, hppa_frame_base, hppa_frame_base_sniffer): 
+	Remove superfluous definitions.
+	(hppa_gdbarch_init): Remove superfluous frame base sniffer.
+
 2004-06-07  Guy Martin  <gmsoft@gentoo.org>
 
 	Committed by Randolph Chung.
diff --git a/gdb/hppa-tdep.c b/gdb/hppa-tdep.c
index 8bad243..7861fc3 100644
--- a/gdb/hppa-tdep.c
+++ b/gdb/hppa-tdep.c
@@ -1783,7 +1783,8 @@ hppa_frame_cache (struct frame_info *next_frame, void **this_cache)
         and saved on the stack, the Save_SP flag is set.  We use this to
         decide whether to use the frame pointer for unwinding.
 	
-	fp should never be zero here; checking just in case. 
+	fp may be zero if it is not available in an inner frame because
+	it has been modified by not yet saved.
 	
         TODO: For the HP compiler, maybe we should use the alloca_frame flag 
 	instead of Save_SP.  */
@@ -1799,10 +1800,9 @@ hppa_frame_cache (struct frame_info *next_frame, void **this_cache)
 	  fprintf_unfiltered (gdb_stdlog, " (base=0x%s) [frame pointer] }",
  	    paddr_nz (cache->base));
       }
-     else if (frame_pc_unwind (next_frame) >= prologue_end)
+     else if (u->Save_SP 
+	      && trad_frame_addr_p (cache->saved_regs, HPPA_SP_REGNUM))
       {
-        if (u->Save_SP && trad_frame_addr_p (cache->saved_regs, HPPA_SP_REGNUM))
-          {
             /* Both we're expecting the SP to be saved and the SP has been
 	       saved.  The entry SP value is saved at this frame's SP
 	       address.  */
@@ -1811,29 +1811,17 @@ hppa_frame_cache (struct frame_info *next_frame, void **this_cache)
 	    if (hppa_debug)
 	      fprintf_unfiltered (gdb_stdlog, " (base=0x%s) [saved] }",
 			          paddr_nz (cache->base));
-          }
-        else
-          {
-            /* The prologue has been slowly allocating stack space.  Adjust
-	     the SP back.  */
-            cache->base = this_sp - frame_size;
-	    if (hppa_debug)
-	      fprintf_unfiltered (gdb_stdlog, " (base=0x%s) [unwind adjust] } ",
-			          paddr_nz (cache->base));
-
-          }
       }
     else
       {
-	/* This frame has not yet been created. */
-        cache->base = this_sp;
-
+        /* The prologue has been slowly allocating stack space.  Adjust
+	   the SP back.  */
+        cache->base = this_sp - frame_size;
 	if (hppa_debug)
-	  fprintf_unfiltered (gdb_stdlog, " (base=0x%s) [before prologue] } ",
+	  fprintf_unfiltered (gdb_stdlog, " (base=0x%s) [unwind adjust] } ",
 			      paddr_nz (cache->base));
 
       }
-
     trad_frame_set_value (cache->saved_regs, HPPA_SP_REGNUM, cache->base);
   }
 
@@ -1860,6 +1848,14 @@ hppa_frame_cache (struct frame_info *next_frame, void **this_cache)
 	}
     }
 
+  /* If the frame pointer was not saved in this frame, but we should be saving
+     it, set it to an invalid value so that another frame will not pick up the 
+     wrong frame pointer.  This can happen if we start unwinding after the 
+     frame pointer has been modified, but before we've saved it to the
+     stack.  */
+  if (u->Save_SP && !trad_frame_addr_p (cache->saved_regs, HPPA_FP_REGNUM))
+    trad_frame_set_value (cache->saved_regs, HPPA_FP_REGNUM, 0);
+
   {
     /* Convert all the offsets into addresses.  */
     int reg;
@@ -2017,28 +2013,6 @@ hppa_fallback_unwind_sniffer (struct frame_info *next_frame)
   return &hppa_fallback_frame_unwind;
 }
 
-static CORE_ADDR
-hppa_frame_base_address (struct frame_info *next_frame,
-				void **this_cache)
-{
-  struct hppa_frame_cache *info = hppa_frame_cache (next_frame,
-							   this_cache);
-  return info->base;
-}
-
-static const struct frame_base hppa_frame_base = {
-  &hppa_frame_unwind,
-  hppa_frame_base_address,
-  hppa_frame_base_address,
-  hppa_frame_base_address
-};
-
-static const struct frame_base *
-hppa_frame_base_sniffer (struct frame_info *next_frame)
-{
-  return &hppa_frame_base;
-}
-
 /* Stub frames, used for all kinds of call stubs.  */
 struct hppa_stub_unwind_cache
 {
@@ -2554,7 +2528,6 @@ hppa_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   frame_unwind_append_sniffer (gdbarch, hppa_stub_unwind_sniffer);
   frame_unwind_append_sniffer (gdbarch, hppa_frame_unwind_sniffer);
   frame_unwind_append_sniffer (gdbarch, hppa_fallback_unwind_sniffer);
-  frame_base_append_sniffer (gdbarch, hppa_frame_base_sniffer);
 
   return gdbarch;
 }