[PATCH] D69499: [X86] Narrow i64 compares with constant to i32 when the upper 32-bits are known zero.

[Simon Pilgrim via Phabricator via llvm-commits]

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

LGTM



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Comment at: llvm/lib/Target/X86/X86ISelLowering.cpp:20187
+      cast<ConstantSDNode>(Op1)->getAPIntValue().getActiveBits() <= 32 &&
+      DAG.MaskedValueIsZero(Op0, APInt::getHighBitsSet(64, 32))) {
+    CmpVT = MVT::i32;
----------------
craig.topper wrote:
> RKSimon wrote:
> > Do the equivalent for signed with ComputeNumSignBits?
> I tried, but it affected no lit tests.
Fair enough - add a FIXME if you think its worth it.


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https://reviews.llvm.org/D69499