[PATCH] D62818: [InstCombine] Introduce fold for icmp pred (and X, (sh signbit, Y)), 0.

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


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Comment at: lib/Transforms/InstCombine/InstCombineCompares.cpp:1792-1795
+                           m_CombineAnd(m_Shift(m_SignMask(), m_Value(V1)),
+                                        m_Value(Shift)),
+                           m_CombineOr(m_Shl(m_Value(), m_Value()),
+                                       m_LShr(m_Value(), m_Value()))),
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m_LogicalShift() ?


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Comment at: test/Transforms/InstCombine/signbit-shl-and-icmpeq-zero.ll:180
 
 ; Negative tests
 
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I didn't step through the transforms, but it seems wrong to call this a 'negative test'. This patch must have fired and allowed further simplification?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62818/new/

https://reviews.llvm.org/D62818