[llvm] [VPlan] Simplify logical-op identities (PR #156345)

[Luke Lau via llvm-commits]

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@@ -341,64 +341,23 @@ exit:
 define void @redundant_and_2(ptr %dst, i1 %c.0, i1 %c.1) {
 ; CHECK-LABEL: @redundant_and_2(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    br i1 false, label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
-; CHECK:       vector.ph:
-; CHECK-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <4 x i1> poison, i1 [[C_0:%.*]], i64 0
-; CHECK-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <4 x i1> [[BROADCAST_SPLATINSERT1]], <4 x i1> poison, <4 x i32> zeroinitializer
-; CHECK-NEXT:    [[TMP0:%.*]] = xor <4 x i1> [[BROADCAST_SPLAT2]], splat (i1 true)
-; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]
-; CHECK:       vector.body:
-; CHECK-NEXT:    [[TMP3:%.*]] = select <4 x i1> <i1 true, i1 true, i1 true, i1 false>, <4 x i1> [[TMP0]], <4 x i1> zeroinitializer
-; CHECK-NEXT:    [[TMP4:%.*]] = select <4 x i1> [[TMP3]], <4 x i1> zeroinitializer, <4 x i1> zeroinitializer
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lukel97 wrote:

Just checking, this is from x && false -> false?

https://github.com/llvm/llvm-project/pull/156345