[PATCH] D123399: [InstCombine] Fold sub(add(x,y),min/max(x,y)) -> max/min(x,y) (PR38280)

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp:2017
+    if (match(Op0, m_Add(m_Value(X), m_Value(Y))) &&
+        match(Op1, m_c_MaxOrMin(m_Specific(X), m_Specific(Y))) &&
+        (Op0->hasOneUse() || Op1->hasOneUse())) {
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I believe m_c_MaxOrMin also accepts min/max in select form, which would then assert with the intrinsic cast. Unless we want to adjust the matcher (which we might well want to do now that we canonicalize to intrinsic form, but probably independently of this change) I'd suggest a dyn_cast to MinMaxIntrinsic.


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  https://reviews.llvm.org/D123399/new/

https://reviews.llvm.org/D123399