[PATCH] Fix powerpc movsi_from_sf define_insn_and_split constraints (PR target/79354)

[Jakub Jelinek]

On Fri, Feb 03, 2017 at 09:59:45AM -0600, Segher Boessenkool wrote:
> Hi Jakub,
> 
> On Fri, Feb 03, 2017 at 10:10:47AM +0100, Jakub Jelinek wrote:
> > As mentioned in the PR, for the following testcase we emit a power9
> > instruction even with -mcpu=power8.  Similar movsf_hardfloat instruction
> > uses wb constraint for the stxssp insn source rather than wu, which it
> > only uses for stxsspx (power7?).
> > 
> > Bootstrapped/regtested on powerpc64{,le}-linux, ok for trunk?
> 
> Yes please.  Thanks!
> 
> Some testcase stuff below...
> 
> 
> > --- gcc/testsuite/gcc.target/powerpc/pr79354.c.jj	2017-02-03 02:37:44.147938375 +0100
> > +++ gcc/testsuite/gcc.target/powerpc/pr79354.c	2017-02-03 02:38:34.838303987 +0100
> > @@ -0,0 +1,23 @@
> > +/* PR target/79354 */
> > +/* { dg-do compile { target { powerpc64*-*-* && lp64 } } } */
> 
> powerpc*-*-* instead?  And why is lp64 needed?

Neither is needed, I've copied/adjusted the dg-do.*dg-options
block from another testcase and missed this.

> > +/* { dg-skip-if "do not override -mcpu" { powerpc*-*-* } { "-mcpu=*" } { "-mcpu=power8" } } */
> > +/* { dg-require-effective-target powerpc_p8vector_ok } */
> > +/* { dg-options "-mcpu=power8 -O2" } */
> > +/* { dg-final { scan-assembler-not "stxssp\[^x]" } } */
> 
> \M is nicer and more future-proof, but this works.

{\mstxssp\M} is what I've committed after retesting it without/with the
rs6000.md change.  Thanks.

2017-02-03  Jakub Jelinek  <jakub@redhat.com>

	PR target/79354
	* config/rs6000/rs6000.md (movsi_from_sf): Use wb constraint instead of
	wu for stxssp alternative.

	* gcc.target/powerpc/pr79354.c: New test.
	* gcc.c-torture/execute/pr79354.c: New test.

--- gcc/config/rs6000/rs6000.md.jj	2017-02-02 11:04:27.000000000 +0100
+++ gcc/config/rs6000/rs6000.md	2017-02-03 02:29:42.754962983 +0100
@@ -6814,7 +6814,7 @@ (define_insn_and_split "movsi_from_sf"
 
 	(unspec:SI [(match_operand:SF 1 "input_operand"
 		"r,          m,           Z,           Z,        r,
-		 f,          wu,          wu,          wIwH,     r,
+		 f,          wb,          wu,          wIwH,     r,
 		 wK")]
 		    UNSPEC_SI_FROM_SF))
 
--- gcc/testsuite/gcc.target/powerpc/pr79354.c.jj	2017-02-03 02:37:44.147938375 +0100
+++ gcc/testsuite/gcc.target/powerpc/pr79354.c	2017-02-03 02:38:34.838303987 +0100
@@ -0,0 +1,22 @@
+/* PR target/79354 */
+/* { dg-do compile } */
+/* { dg-skip-if "do not override -mcpu" { powerpc*-*-* } { "-mcpu=*" } { "-mcpu=power8" } } */
+/* { dg-require-effective-target powerpc_p8vector_ok } */
+/* { dg-options "-mcpu=power8 -O2" } */
+/* { dg-final { scan-assembler-not {\mstxssp\M} } } */
+
+int b, f, g;
+float e;
+unsigned long d;
+
+void
+foo (int *a)
+{
+  for (g = 0; g < 32; g++)
+    if (f)
+      {
+        e = d;
+        __builtin_memcpy (&b, &e, sizeof (float));
+        b = *a;
+      }
+}
--- gcc/testsuite/gcc.c-torture/execute/pr79354.c.jj	2017-02-03 02:36:36.746781897 +0100
+++ gcc/testsuite/gcc.c-torture/execute/pr79354.c	2017-02-03 02:36:07.000000000 +0100
@@ -0,0 +1,30 @@
+/* PR target/79354 */
+
+int b, f, g;
+float e;
+unsigned long d;
+
+__attribute__((noinline, noclone)) void
+foo (int *a)
+{
+  for (g = 0; g < 32; g++)
+    if (f)
+      {
+        e = d;
+        __builtin_memcpy (&b, &e, sizeof (float));
+        b = *a;
+      }
+}
+
+int
+main ()
+{
+  int h = 5;
+  f = 1;
+  asm volatile ("" : : : "memory");
+  foo (&h);
+  asm volatile ("" : : : "memory");
+  foo (&b);
+  asm volatile ("" : : : "memory");
+  return 0;
+}


	Jakub