[PATCH] D119715: [InstCombine] Fold sub(0,and(lshr(X,C),1)) --> ashr(shl(X,(BW-1)-C),BW-1) (PR53610)

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri accepted this revision.
lebedev.ri added a comment.
This revision is now accepted and ready to land.

LGTM, thank you.



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Comment at: llvm/lib/Transforms/InstCombine/InstCombineNegator.cpp:253
+    Constant *ShAmt;
+    // sub(C1,and(lshr(X,C2),1)) --> add(ashr(shl(X,(BW-1)-C2),BW-1),C1)
+    if (match(I, m_c_And(m_OneUse(m_TruncOrSelf(
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https://reviews.llvm.org/D119715