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

[Luke Lau via llvm-commits]

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@@ -16,128 +16,106 @@ define void @test_blend_feeding_replicated_store_1(i64 %N, ptr noalias %src, ptr
 ; CHECK-NEXT:    [[TMP1:%.*]] = icmp eq i64 [[N_MOD_VF]], 0
 ; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[TMP1]], i64 16, i64 [[N_MOD_VF]]
 ; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[TMP43]], [[TMP2]]
-; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <16 x ptr> poison, ptr [[DST]], i64 0
-; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <16 x ptr> [[BROADCAST_SPLATINSERT]], <16 x ptr> poison, <16 x i32> zeroinitializer
 ; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
 ; CHECK:       [[VECTOR_BODY]]:
 ; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[PRED_STORE_CONTINUE30:.*]] ]
 ; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr inbounds i32, ptr [[SRC]], i64 [[INDEX]]
 ; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <16 x i32>, ptr [[TMP4]], align 4
-; CHECK-NEXT:    [[TMP6:%.*]] = icmp slt <16 x i32> [[WIDE_LOAD]], zeroinitializer
-; CHECK-NEXT:    [[TMP7:%.*]] = select <16 x i1> [[TMP6]], <16 x i1> zeroinitializer, <16 x i1> zeroinitializer
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lukel97 wrote:

And this is also from `x && false -> false`. So do we have any tests affected by `x || true -> true`? Is that simplification dead?

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