dwarf2out.c (dwarf2out_stack_adjust): Always track the stack pointer...

* dwarf2out.c (dwarf2out_stack_adjust): Always track the stack
pointer, instead of assuming it is possible to derive the
correct args size from a call insn.

From-SVN: r112170

2 files changed, 29 insertions, 26 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a568a02..a63b7d0 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2006-03-17  Alexandre Oliva  <aoliva@redhat.com>
+
+	* dwarf2out.c (dwarf2out_stack_adjust): Always track the stack
+	pointer, instead of assuming it is possible to derive the
+	correct args size from a call insn.
+
 2006-03-16  Jan-Benedict Glaw  <jbglaw@lug-owl.de>
 
 	* rtl.h (CONST_INT_P): Define.
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 9308cce..ccfb5df 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -1072,7 +1072,7 @@ stack_adjust_offset (rtx pattern)
    much extra space it needs to pop off the stack.  */
 
 static void
-dwarf2out_stack_adjust (rtx insn, bool after_p)
+dwarf2out_stack_adjust (rtx insn, bool after_p ATTRIBUTE_UNUSED)
 {
   HOST_WIDE_INT offset;
   const char *label;
@@ -1085,31 +1085,7 @@ dwarf2out_stack_adjust (rtx insn, bool after_p)
   if (prologue_epilogue_contains (insn) || sibcall_epilogue_contains (insn))
     return;
 
-  /* If only calls can throw, and we have a frame pointer,
-     save up adjustments until we see the CALL_INSN.  */
-  if (!flag_asynchronous_unwind_tables && cfa.reg != STACK_POINTER_REGNUM)
-    {
-      if (CALL_P (insn) && !after_p)
-	{
-	  /* Extract the size of the args from the CALL rtx itself.  */
-	  insn = PATTERN (insn);
-	  if (GET_CODE (insn) == PARALLEL)
-	    insn = XVECEXP (insn, 0, 0);
-	  if (GET_CODE (insn) == SET)
-	    insn = SET_SRC (insn);
-	  gcc_assert (GET_CODE (insn) == CALL);
-	  dwarf2out_args_size ("", INTVAL (XEXP (insn, 1)));
-	}
-      return;
-    }
-
-  if (CALL_P (insn) && !after_p)
-    {
-      if (!flag_asynchronous_unwind_tables)
-	dwarf2out_args_size ("", args_size);
-      return;
-    }
-  else if (BARRIER_P (insn))
+  if (BARRIER_P (insn))
     {
       /* When we see a BARRIER, we know to reset args_size to 0.  Usually
 	 the compiler will have already emitted a stack adjustment, but
@@ -1131,9 +1107,20 @@ dwarf2out_stack_adjust (rtx insn, bool after_p)
 	if (GET_CODE (XVECEXP (PATTERN (insn), 0, i)) == SET)
 	  offset += stack_adjust_offset (XVECEXP (PATTERN (insn), 0, i));
     }
+  else if (GET_CODE (insn) == CALL_INSN)
+    offset = 0;
   else
     return;
 
+  /* We handle this separately because we want stack adjustments in a
+     CALL_INSN to be handled.  */;
+  if (GET_CODE (insn) == CALL_INSN)
+    {
+      /* If only calls can throw, adjust args_size only at call sites.  */
+      if (!flag_asynchronous_unwind_tables)
+	dwarf2out_args_size ("", args_size);
+    }
+
   if (offset == 0)
     return;
 
@@ -1148,6 +1135,16 @@ dwarf2out_stack_adjust (rtx insn, bool after_p)
   if (args_size < 0)
     args_size = 0;
 
+  /* If only calls can throw and we have a frame pointer, we'll save
+     up adjustments until we see the CALL_INSN.  We used to return
+     early and derive args_size from NARGS in the CALL_INSN itself,
+     but that doesn't compute the right value if we have nested call
+     expansions, e.g., stack adjustments for a call have already been
+     emitted, and then we issue another call to compute an argument
+     for the enclosing call (i.e., bar (foo ())).  */
+  if (!flag_asynchronous_unwind_tables && cfa.reg != STACK_POINTER_REGNUM)
+    return;
+
   label = dwarf2out_cfi_label ();
   def_cfa_1 (label, &cfa);
   if (flag_asynchronous_unwind_tables)