From: Uros Bizjak <ubizjak@gmail.com>
Date: Thu, 23 Nov 2023 15:17:57 +0000 (+0100)
Subject: i386: Wrong code with __builtin_parityl [PR112672]
X-Git-Tag: basepoints/gcc-15~4354
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b2d17bdd45b582b93e89c00b04763a45f97d7a34;p=thirdparty%2Fgcc.git

i386: Wrong code with __builtin_parityl [PR112672]

gen_parityhi2_cmp instruction clobbers its input operand, so use
a temporary register in the call to gen_parityhi2_cmp.

	PR target/112672

gcc/ChangeLog:

	* config/i386/i386.md (parityhi2):
	Use temporary register in the call to gen_parityhi2_cmp.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/pr112672.c: New test.
---

diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 99bb909b244d..41de9537a405 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -20031,8 +20031,10 @@
   "! TARGET_POPCNT"
 {
   rtx scratch = gen_reg_rtx (QImode);
+  rtx tmp = gen_reg_rtx (HImode);
 
-  emit_insn (gen_parityhi2_cmp (operands[1]));
+  emit_move_insn (tmp, operands[1]);
+  emit_insn (gen_parityhi2_cmp (tmp));
 
   ix86_expand_setcc (scratch, ORDERED,
 		     gen_rtx_REG (CCmode, FLAGS_REG), const0_rtx);
diff --git a/gcc/testsuite/gcc.target/i386/pr112672.c b/gcc/testsuite/gcc.target/i386/pr112672.c
new file mode 100644
index 000000000000..583e9fdfb8b9
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112672.c
@@ -0,0 +1,23 @@
+/* PR target/112672 */
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+typedef unsigned short u16;
+
+u16 g = 254;
+
+static inline u16
+foo (u16 u)
+{
+  u *= g;
+  return u + __builtin_parityl (u);
+}
+
+int
+main (void)
+{
+  u16 x = foo (4);
+  if (x != 4 * 254 + 1)
+    __builtin_abort ();
+  return 0;
+}