[gcc r13-5448] Do not try to logical fold floating point relations.

[gcc r13-5448] Do not try to logical fold floating point relations.

[Andrew Macleod]

https://gcc.gnu.org/g:ec5e99e95954fd629283a9c9572193dd95471fea

commit r13-5448-gec5e99e95954fd629283a9c9572193dd95471fea
Author: Andrew MacLeod <amacleod@redhat.com>
Date:   Wed Jan 25 11:13:23 2023 -0500

    Do not try to logical fold floating point relations.
    
    relation_fold_and_or looks for relations among common operands feeding
    logical ands and ors.  With no knowledge of NANs, it should not attempt
    to do this with floating point ssa names.
    
            PR tree-optimization/108447
            gcc/
            * gimple-range-fold.cc (old_using_range::relation_fold_and_or):
            Do not attempt to fold HONOR_NAN types.
    
            gcc/testsuite/
            * gcc.dg/pr108447.c: New.

Diff:
---
 gcc/gimple-range-fold.cc        |  3 +++
 gcc/testsuite/gcc.dg/pr108447.c | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/gcc/gimple-range-fold.cc b/gcc/gimple-range-fold.cc
index 91eb6298254..9c5359a3fc6 100644
--- a/gcc/gimple-range-fold.cc
+++ b/gcc/gimple-range-fold.cc
@@ -1039,6 +1039,9 @@ fold_using_range::relation_fold_and_or (irange& lhs_range, gimple *s,
   if (!ssa1_dep1 || !ssa1_dep2 || !ssa2_dep1 || !ssa2_dep2)
     return;
 
+  if (HONOR_NANS (TREE_TYPE (ssa1_dep1)))
+    return;
+
   // Make sure they are the same dependencies, and detect the order of the
   // relationship.
   bool reverse_op2 = true;
diff --git a/gcc/testsuite/gcc.dg/pr108447.c b/gcc/testsuite/gcc.dg/pr108447.c
new file mode 100644
index 00000000000..cfbaba6d0aa
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr108447.c
@@ -0,0 +1,33 @@
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+__attribute__((noipa)) int
+foo (float x, float y)
+{
+  _Bool cmp1 = x <= y;
+  _Bool cmp2 = x >= y;
+  if (cmp1 && cmp2)
+    return 1;
+  else if (!cmp1 && !cmp2)
+    return -1;
+  return 0;
+}
+
+int
+main ()
+{
+  if (foo (0.0f, __builtin_nanf ("")) != -1)
+    __builtin_abort ();
+  if (foo (__builtin_nanf (""), -42.0f) != -1)
+    __builtin_abort ();
+  if (foo (0.0f, -0.0f) != 1)
+    __builtin_abort ();
+  if (foo (42.0f, 42.0f) != 1)
+    __builtin_abort ();
+  if (foo (42.0f, -0.0f) != 0)
+    __builtin_abort ();
+  if (foo (0.0f, -42.0f) != 0)
+    __builtin_abort ();
+  return 0;
+}
+