From: Nathan Sidwell <nathan@codesourcery.com>
Date: Thu, 21 Dec 2006 09:03:18 +0000 (+0000)
Subject: re PR target/28966 (-maltivec -m32 causes the stack to be saved and restored even... 
X-Git-Tag: releases/gcc-4.3.0~7877
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=970af8677126773a729c5fde809ab307b6494082;p=thirdparty%2Fgcc.git

re PR target/28966 (-maltivec -m32 causes the stack to be saved and restored even though there is no need for it)

gcc/
	PR target/28966
	PR target/29248
	* reload1.c (reload): Realign stack after it changes size.
gcc/testsuite/
	PR target/28966
	PR target/29248
	* gcc.dg/rs6000-leaf.c: New.

From-SVN: r120102
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 40f7c77cbcac..2e3f9d9df874 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2006-12-21  Nathan Sidwell  <nathan@codesourcery.com>
+
+	PR target/28966
+	PR target/29248
+	* reload1.c (reload): Realign stack after it changes size.
+
 2006-12-20  Roger Sayle  <roger@eyesopen.com>
 
 	* simplify-rtx.c (simplify_subreg): Use the correct mode when
diff --git a/gcc/reload1.c b/gcc/reload1.c
index 454383581e8b..efa1a397212f 100644
--- a/gcc/reload1.c
+++ b/gcc/reload1.c
@@ -888,16 +888,8 @@ reload (rtx first, int global)
     {
       int something_changed;
       int did_spill;
-
       HOST_WIDE_INT starting_frame_size;
 
-      /* Round size of stack frame to stack_alignment_needed.  This must be done
-	 here because the stack size may be a part of the offset computation
-	 for register elimination, and there might have been new stack slots
-	 created in the last iteration of this loop.  */
-      if (cfun->stack_alignment_needed)
-        assign_stack_local (BLKmode, 0, cfun->stack_alignment_needed);
-
       starting_frame_size = get_frame_size ();
 
       set_initial_elim_offsets ();
@@ -964,6 +956,20 @@ reload (rtx first, int global)
       /* If we allocated another stack slot, redo elimination bookkeeping.  */
       if (starting_frame_size != get_frame_size ())
 	continue;
+      if (starting_frame_size && cfun->stack_alignment_needed)
+	{
+	  /* If we have a stack frame, we must align it now.  The
+	     stack size may be a part of the offset computation for
+	     register elimination.  So if this changes the stack size,
+	     then repeat the elimination bookkeeping.  We don't
+	     realign when there is no stack, as that will cause a
+	     stack frame when none is needed should
+	     STARTING_FRAME_OFFSET not be already aligned to
+	     STACK_BOUNDARY.  */
+	  assign_stack_local (BLKmode, 0, cfun->stack_alignment_needed);
+	  if (starting_frame_size != get_frame_size ())
+	    continue;
+	}
 
       if (caller_save_needed)
 	{
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index a1e84b11b5ef..d7087428a6f7 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2006-12-21  Nathan Sidwell  <nathan@codesourcery.com>
+
+	PR target/28966
+	PR target/29248
+	* gcc.dg/rs6000-leaf.c: New.
+
 2006-12-20  Tobias Schlüter  <tobias.schlueter@physik.uni-muenchen.de>
 
 	PR fortran/25392
diff --git a/gcc/testsuite/gcc.dg/rs6000-leaf.c b/gcc/testsuite/gcc.dg/rs6000-leaf.c
new file mode 100644
index 000000000000..079418930da7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/rs6000-leaf.c
@@ -0,0 +1,8 @@
+/* { dg-do compile { target rs6000-*-* } }  */
+/* { dg-options "-O2" } */
+/* { dg-final { scan-assembler-not "\tstwu 1,-\[0-9\]*(1)\n" } } */
+
+int Leaf (int i)
+{
+  return i + 1;
+}