[PATCH] Fix -O0 AVX512 comparison ICE (PR target/78227)

[Jakub Jelinek]

Hi!

The following testcases ICE at -O0, because ix86_expand_sse_cmp avoid using
the passed in dest only if optimize or if there is some value overlap, but
we actually need to do that also if we have a maskcmp where we want to use
a different mode than dest has.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2016-11-07  Jakub Jelinek  <jakub@redhat.com>

	PR target/78227
	* config/i386/i386.c (ix86_expand_sse_cmp): Force dest into
	cmp_mode argument even for -O0 if cmp_mode != mode and maskcmp.

	* gcc.target/i386/pr78227-1.c: New test.
	* gcc.target/i386/pr78227-2.c: New test.

--- gcc/config/i386/i386.c.jj	2016-11-04 20:09:48.000000000 +0100
+++ gcc/config/i386/i386.c	2016-11-07 10:14:15.625018144 +0100
@@ -23561,6 +23561,7 @@ ix86_expand_sse_cmp (rtx dest, enum rtx_
     cmp_op1 = force_reg (cmp_ops_mode, cmp_op1);
 
   if (optimize
+      || (cmp_mode != mode && maskcmp)
       || (op_true && reg_overlap_mentioned_p (dest, op_true))
       || (op_false && reg_overlap_mentioned_p (dest, op_false)))
     dest = gen_reg_rtx (maskcmp ? cmp_mode : mode);
--- gcc/testsuite/gcc.target/i386/pr78227-1.c.jj	2016-11-07 10:15:52.606762613 +0100
+++ gcc/testsuite/gcc.target/i386/pr78227-1.c	2016-11-07 10:24:58.821480125 +0100
@@ -0,0 +1,30 @@
+/* PR target/78227 */
+/* { dg-do compile } */
+/* { dg-options "-mavx512f -O0 -Wno-psabi" } */
+
+typedef int V __attribute__((vector_size (64)));
+typedef long long int W __attribute__((vector_size (64)));
+
+V
+foo1 (V v)
+{
+  return v > 0;
+}
+
+V
+bar1 (V v)
+{
+  return v != 0;
+}
+
+W
+foo2 (W w)
+{
+  return w > 0;
+}
+
+W
+bar2 (W w)
+{
+  return w != 0;
+}
--- gcc/testsuite/gcc.target/i386/pr78227-2.c.jj	2016-11-07 10:22:17.055670476 +0100
+++ gcc/testsuite/gcc.target/i386/pr78227-2.c	2016-11-07 10:25:03.722413765 +0100
@@ -0,0 +1,30 @@
+/* PR target/78227 */
+/* { dg-do compile } */
+/* { dg-options "-mavx512bw -O0 -Wno-psabi" } */
+
+typedef signed char V __attribute__((vector_size (64)));
+typedef short int W __attribute__((vector_size (64)));
+
+V
+foo1 (V v)
+{
+  return v > 0;
+}
+
+V
+bar1 (V v)
+{
+  return v != 0;
+}
+
+W
+foo2 (W w)
+{
+  return w > 0;
+}
+
+W
+bar2 (W w)
+{
+  return w != 0;
+}

	Jakub