* gcc/config/i386/i386.opt (-mstackrealign): New flag. *

	gcc/config/i386/i386.c (force_align_arg_pointer): New attribute.
	(ix86_handle_cconv_attribute): Emit error when
	force_align_arg_pointer attribute collides with too many regparms.
	(ix86_function_regparm): Limit regparms when used with
	force_align_arg_pointer attribute.  (ix86_internal_arg_pointer):
	Support stack-realigning prologue in non-main functions.  Emit
	warning for nested functions under -mstackrealign, emit error for
	nested functions with force_align_arg_pointer attribute.
	* gcc/doc/extend.texi (force_align_arg_pointer): Document it.
	* gcc/doc/invoke.texi (-mstackrealign): Document it.
	* testsuite/gcc.target/i386/20060512-1.c: New.
	* testsuite/gcc.target/i386/20060512-2.c: New.
	* testsuite/gcc.target/i386/20060512-3.c: New.
	* testsuite/gcc.target/i386/20060512-4.c: New.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@113880 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 28 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.target/i386/20060512-3.c b/gcc/testsuite/gcc.target/i386/20060512-3.c
new file mode 100644
index 00000000000..72f0da00bb6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/20060512-3.c
@@ -0,0 +1,28 @@
+/* { dg-do run { target i?86-*-* } } */
+/* { dg-options "-std=gnu99 -mstackrealign" } */
+#include <emmintrin.h>
+__m128i __attribute__ ((__noinline__))
+vector_using_function ()
+{
+  volatile __m128i vx;	/* We want to force a vector-aligned store into the stack.  */
+  vx = _mm_xor_si128 (vx, vx);
+  return vx;
+}
+int __attribute__ ((__noinline__))
+self_aligning_function (int x, int y)
+{
+  __m128i ignored = vector_using_function ();
+  return (x + y);
+}
+int g_1 = 20;
+int g_2 = 22;
+int
+main ()
+{
+  int result;
+  asm ("pushl %esi");		/* Disalign runtime stack.  */
+  result = self_aligning_function (g_1, g_2);
+  asm ("popl %esi");
+  if (result != 42)
+    abort ();
+}