[llvm] [InstCombine] Remove some of the complexity-based canonicalization (PR #91185)

[via llvm-commits]

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@@ -549,8 +549,9 @@ define float @test16_reassoc(float %a, float %b, float %z) {
 
 define float @test17(float %a, float %b, float %z) {
 ; CHECK-LABEL: @test17(
-; CHECK-NEXT:    [[TMP1:%.*]] = fmul fast float [[Z:%.*]], 4.000000e+01
-; CHECK-NEXT:    [[F:%.*]] = fmul fast float [[TMP1]], [[A:%.*]]
+; CHECK-NEXT:    [[C:%.*]] = fmul fast float [[Z:%.*]], -4.000000e+01
+; CHECK-NEXT:    [[TMP1:%.*]] = fneg fast float [[A:%.*]]
+; CHECK-NEXT:    [[F:%.*]] = fmul fast float [[C]], [[TMP1]]
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goldsteinn wrote:

regression + below

https://github.com/llvm/llvm-project/pull/91185