[clang] [llvm] [InstCombine] Fold select(X >s 0, 0, -X) | smax(X, 0) to abs(X) (PR #165200)

[Wenju He via llvm-commits]

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@@ -3997,6 +3997,27 @@ static Value *foldOrUnsignedUMulOverflowICmp(BinaryOperator &I,
   return nullptr;
 }
 
+/// Fold select(X >s 0, 0, -X) | smax(X, 0) --> abs(X)
+///      select(X <s 0, -X, 0) | smax(X, 0) --> abs(X)
+static Value *FoldOrOfSelectSmaxToAbs(BinaryOperator &I,
+                                      InstCombiner::BuilderTy &Builder) {
+  Value *X;
+  Value *Sel;
+  if (match(&I, m_c_Or(m_Value(Sel), m_OneUse(m_Intrinsic<Intrinsic::smax>(
----------------
wenju-he wrote:

> Use m_SMax

done

https://github.com/llvm/llvm-project/pull/165200