[PATCH] D36505: [InstCombine] Make (X|C1)^C2 -> X^(C1^C2) iff X&~C1 == 0 work for splat vectors

[Sanjay Patel via Phabricator via llvm-commits]

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

LGTM.



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Comment at: lib/Transforms/InstCombine/InstCombineAndOrXor.cpp:2393-2394
+
+      // (X|C1)^C2 -> X^(C1^C2) iff X&~C1 == 0
+      if (match(Op0, m_Or(m_Value(V), m_APInt(C))) &&
+          MaskedValueIsZero(V, *C, 0, &I)) {
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Nit / potential clean-up: I like to make the variable names match the comment names for easier reading when possible, so I'd pick either 'X' or 'V' and stick with it throughout this block.


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Comment at: test/Transforms/InstCombine/select-with-bitwise-ops.ll:271
 
 define <2 x i32> @test65vec(<2 x i64> %x) {
 ; CHECK-LABEL: @test65vec(
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Are we just changing the mask constant in these 3 tests to prove that MaskedValueIsZero() is working as expected? Might be more interesting to use a shift or zext to clear some bits instead?


https://reviews.llvm.org/D36505