[clang] Fix -fno-unsafe-math-optimizations behavior (PR #89473)

[Andy Kaylor via cfe-commits]

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@@ -318,12 +320,12 @@
 
 // RUN: %clang -### -fassociative-math -freciprocal-math -fno-signed-zeros \
 // RUN:     -fno-trapping-math -ftrapping-math -c %s 2>&1 \
-// RUN:   | FileCheck --check-prefix=CHECK-NO-REASSOC-NO-UNSAFE-MATH %s
+// RUN:   | FileCheck --check-prefix=CHECK-NO-UNSAFE-MATH %s
 
 // CHECK-NO-REASSOC-NO-UNSAFE-MATH: "-cc1"
-// CHECK-NO-REASSOC-NO_UNSAFE-MATH-NOT: "-funsafe-math-optimizations"
-// CHECK-NO-REASSOC-NO_UNSAFE-MATH-NOT: "-mreassociate"
-// CHECK-NO-REASSOC-NO_UNSAFE-MATH-NOT: "-funsafe-math-optimizations"
+// CHECK-NO-REASSOC-NO-UNSAFE-MATH-NOT: "-funsafe-math-optimizations"
+// CHECK-NO-REASSOC-NO-UNSAFE-MATH-NOT: "-mreassociate"
+// CHECK-NO-REASSOC-NO-UNSAFE-MATH-NOT: "-funsafe-math-optimizations"
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andykaylor wrote:

I'd be happy to make that change. I was a little lazy with this test. I just wanted something that tested the change I was making, and then the rest of what I did was just what seemed necessary to make the test pass while still testing the things it meant to test. The whole thing seemed a bit of a mess. I can clean it up some with a bit more effort.

https://github.com/llvm/llvm-project/pull/89473