Hi,
  This patch fixes the ICE reported in PR100736. It removes the condition
check of finite math only flag not setting in "*<code><mode>_cc" pattern.
With or without this flag, we still can use "cror" to check if either
two bits of CC is set or not for "fp_two" codes. We don't need a reverse
comparison (implemented by crnot) here when the finite math flag is set,
as the latency of "cror" and "crnor" are the same.

  Bootstrapped and tested on powerpc64-linux BE and LE with no regressions.
Is this okay for trunk? Any recommendations? Thanks a lot.

ChangeLog
2022-05-26 Haochen Gui <guih...@linux.ibm.com>

gcc/
        * config/rs6000/rs6000.md (*<code><mode>_cc): Remove condition of
        finite math only flag not setting.

gcc/testsuite/
        * gcc.target/powerpc/pr100736.c: New.


patch.diff
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index fdfbc6566a5..a6f9cbc9b8b 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -12995,9 +12995,9 @@ (define_insn_and_split "*<code><mode>_cc"
   [(set (match_operand:GPR 0 "gpc_reg_operand" "=r")
        (fp_two:GPR (match_operand:CCFP 1 "cc_reg_operand" "y")
                  (const_int 0)))]
-  "!flag_finite_math_only"
+  ""
   "#"
-  "&& 1"
+  ""
   [(pc)]
 {
   rtx cc = rs6000_emit_fp_cror (<CODE>, <MODE>mode, operands[1]);
diff --git a/gcc/testsuite/gcc.target/powerpc/pr100736.c 
b/gcc/testsuite/gcc.target/powerpc/pr100736.c
new file mode 100644
index 00000000000..32cb6df6cd9
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr100736.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target powerpc_p8vector_ok } */
+/* { dg-options "-mdejagnu-cpu=power8 -O2 -ffinite-math-only" } */
+
+typedef __attribute__ ((altivec (vector__))) unsigned char v;
+
+int foo (v a, v b)
+{
+  return __builtin_vec_bcdsub_ge (a, b, 0);
+}
+
+/* { dg-final { scan-assembler {\mcror\M} } } */

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