[llvm] [VPlan] Simplify (X && Y) || (X && !Y) -> X. (PR #89386)

[via llvm-commits]

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@@ -223,10 +223,9 @@ define void @test_if_then(ptr noalias %a, ptr readnone %b) #4 {
 ; TFCOMMON-NEXT:    [[TMP10:%.*]] = call <vscale x 2 x i64> @foo_vector(<vscale x 2 x i64> [[WIDE_MASKED_LOAD]], <vscale x 2 x i1> [[TMP9]])
 ; TFCOMMON-NEXT:    [[TMP11:%.*]] = xor <vscale x 2 x i1> [[TMP8]], shufflevector (<vscale x 2 x i1> insertelement (<vscale x 2 x i1> poison, i1 true, i64 0), <vscale x 2 x i1> poison, <vscale x 2 x i32> zeroinitializer)
 ; TFCOMMON-NEXT:    [[TMP12:%.*]] = select <vscale x 2 x i1> [[ACTIVE_LANE_MASK]], <vscale x 2 x i1> [[TMP11]], <vscale x 2 x i1> zeroinitializer
-; TFCOMMON-NEXT:    [[TMP13:%.*]] = or <vscale x 2 x i1> [[TMP9]], [[TMP12]]
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ayalz wrote:

This eliminates only the OR, leaving the two logical ANDs intact, as they are used elsewhere.

https://github.com/llvm/llvm-project/pull/89386