[gcc r15-8461] Use ix86_fp_comparison_operator in cbranchbf4 to avoid ICE.

[hongtao Liu]

https://gcc.gnu.org/g:62a6cafd7f55c6e88a9780b91039257572038535

commit r15-8461-g62a6cafd7f55c6e88a9780b91039257572038535
Author: liuhongt <hongtao.liu@intel.com>
Date:   Mon Mar 17 22:47:11 2025 -0700

    Use ix86_fp_comparison_operator in cbranchbf4 to avoid ICE.
    
    *jcc only supports ix86_fp_comparison_operator for CCFP, when
    comparison code is LT, there's an ICE. W/o AVX10.2, it's ok since
    do_compare_rtx_and_jump will transform LT to GT, but w/ AVX10.2 it
    goes directly into ix86_expand_branch which doesn't handle it.
    
    Use ix86_fp_comparison_operator in cbranchbf4.
    
    gcc/ChangeLog:
    
            PR target/117452
            * config/i386/i386.md (cbranchbf4): Use
            ix86_fp_comparison_operator instead of comparison_operator.
    
    gcc/testsuite/ChangeLog:
    
            * gcc.target/i386/pr117452.c: New test.

Diff:
---
 gcc/config/i386/i386.md                  |  2 +-
 gcc/testsuite/gcc.target/i386/pr117452.c | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index b1cd52382a80..8c7beafd758e 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -1812,7 +1812,7 @@
 	(compare:CC (match_operand:BF 1 "cmp_fp_expander_operand")
 		    (match_operand:BF 2 "cmp_fp_expander_operand")))
    (set (pc) (if_then_else
-	      (match_operator 0 "comparison_operator"
+	      (match_operator 0 "ix86_fp_comparison_operator"
 	       [(reg:CC FLAGS_REG)
 		(const_int 0)])
 	      (label_ref (match_operand 3))
diff --git a/gcc/testsuite/gcc.target/i386/pr117452.c b/gcc/testsuite/gcc.target/i386/pr117452.c
new file mode 100644
index 000000000000..4042b4f0a577
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr117452.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-march=x86-64-v3 -mavx10.2 -Ofast" } */
+
+__bf16 b;
+int x;
+
+void
+foo ()
+{
+  if (x < b)
+    x = 0;
+}