[llvm] [DAGCombiner] Remove `UnsafeFPMath` usage in `visitFSUBForFMACombine` etc. (PR #145637)

[Simon Pilgrim via llvm-commits]

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@@ -29,28 +34,37 @@ define double @unsafe_fp_math_off(double %x) #0 {
 ; CHECK-LABEL: unsafe_fp_math_default1:
 define double @unsafe_fp_math_default1(double %x) {
 ; With unsafe math enabled, can change this div to a mul.
-; SAFE:      divsd
 ; UNSAFE:    mulsd
+  %div = fdiv arcp double %x, 3.0
+  ret double %div
+}
+; CHECK-LABEL: safe_fp_math_default1:
+define double @safe_fp_math_default1(double %x) {
+; With unsafe math enabled, can change this div to a mul.
+; SAFE:      divsd
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RKSimon wrote:

lost UNSAFE check?

https://github.com/llvm/llvm-project/pull/145637