[ValueTracking] Update `Ordered` when both operands are non-NaN. (#143349)

When the original predicate is ordered and both operands are non-NaN,
`Ordered` should be set to true. This variable still matters even if
both operands are non-NaN because FMF only applies to select, not fcmp.

Closes https://github.com/llvm/llvm-project/issues/143123.

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/unittests/Analysis/ValueTrackingTest.cpp b/llvm/unittests/Analysis/ValueTrackingTest.cpp
index e23005b..6031898 100644
--- a/llvm/unittests/Analysis/ValueTrackingTest.cpp
+++ b/llvm/unittests/Analysis/ValueTrackingTest.cpp
@@ -187,6 +187,15 @@ TEST_F(MatchSelectPatternTest, FastFMin) {
       "  %A = select i1 %1, float %a, float 5.0\n"
       "  ret float %A\n"
       "}\n");
+  expectPattern({SPF_FMINNUM, SPNB_RETURNS_ANY, true});
+}
+
+TEST_F(MatchSelectPatternTest, FastFMinUnordered) {
+  parseAssembly("define float @test(float %a) {\n"
+                "  %1 = fcmp nnan ult float %a, 5.0\n"
+                "  %A = select i1 %1, float %a, float 5.0\n"
+                "  ret float %A\n"
+                "}\n");
   expectPattern({SPF_FMINNUM, SPNB_RETURNS_ANY, false});
 }