[llvm] [ValueTracking] Fix computeKnownFPClass for fpext (PR #81972)

[Yingwei Zheng via llvm-commits]

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@@ -142,7 +142,7 @@ define double @ret_fpext_f32_to_f64_nosub(float nofpclass(sub) %arg0) {
 }
 
 define double @ret_fpext_f32_to_f64_nonorm(float nofpclass(norm) %arg0) {
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dtcxzyw wrote:

It is supported by alive2.
https://github.com/AliveToolkit/alive2/commit/8f12144d4cfa0d58579105293e0338a811da882a

Example: https://alive2.llvm.org/ce/z/NuQqsR



https://github.com/llvm/llvm-project/pull/81972