[llvm] [DAGCombiner] Fix the "subtraction if above a constant threshold" miscompile (PR #140042)

[Piotr Fusik via llvm-commits]

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@@ -12140,11 +12140,16 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) {
     // (select (ult x, C), x, (add x, -C)) -> (umin x, (add x, -C))
     APInt C;
     if (sd_match(Cond1, m_ConstInt(C)) && hasUMin(VT)) {
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pfusik wrote:

Done.

https://github.com/llvm/llvm-project/pull/140042