[PATCH] D103421: [Constants] Extend support for scalable-vector splats

[Fraser Cormack via Phabricator via llvm-commits]

frasercrmck added inline comments.


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Comment at: llvm/test/Transforms/InstCombine/sub.ll:862
+; CHECK-LABEL: @test44scalablevecminval(
+; CHECK-NEXT:    [[SUB:%.*]] = add <vscale x 2 x i16> [[X:%.*]], shufflevector (<vscale x 2 x i16> insertelement (<vscale x 2 x i16> undef, i16 -32768, i32 0), <vscale x 2 x i16> undef, <vscale x 2 x i32> zeroinitializer)
+; CHECK-NEXT:    ret <vscale x 2 x i16> [[SUB]]
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This isn't combined to `xor` as above because the pattern in `visitSub` uses `m_ImmConstant` which matches `Constant` but explicitly not `ConstantExpr`. Still, it's a call to `isNotMinSignedValue` before it, checking that we don't mis-optimize.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D103421/new/

https://reviews.llvm.org/D103421