[llvm] InstCombine: Handle canonicalize in SimplifyDemandedFPClass (PR #173189)

[Yingwei Zheng via llvm-commits]

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@@ -337,8 +325,7 @@ define nofpclass(zero) float @ret_nofpclass_zero_nnan_flag__canonicalize_select_
 ; CHECK-LABEL: define nofpclass(zero) float @ret_nofpclass_zero_nnan_flag__canonicalize_select_unknown_or_snan(
 ; CHECK-SAME: float [[X:%.*]], i1 [[COND:%.*]]) {
 ; CHECK-NEXT:    [[SNAN:%.*]] = call float @returns_snan()
-; CHECK-NEXT:    [[SELECT:%.*]] = select i1 [[COND]], float [[X]], float [[SNAN]]
-; CHECK-NEXT:    [[CANON:%.*]] = call float @llvm.canonicalize.f32(float [[SELECT]])
+; CHECK-NEXT:    [[CANON:%.*]] = call float @llvm.canonicalize.f32(float [[X]])
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dtcxzyw wrote:

Miscompile: https://alive2.llvm.org/ce/z/y6HnJJ

https://github.com/llvm/llvm-project/pull/173189