[llvm] [clang] [clang-tools-extra] [VPlan] Consistently use (Part, 0) for first lane scalar values (PR #80271)

[via cfe-commits]

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@@ -116,8 +116,7 @@ define void @test_widen(ptr noalias %a, ptr readnone %b) #4 {
 ; TFA_INTERLEAVE-NEXT:    [[TMP18:%.*]] = getelementptr inbounds i64, ptr [[TMP15]], i64 [[TMP17]]
 ; TFA_INTERLEAVE-NEXT:    call void @llvm.masked.store.nxv2i64.p0(<vscale x 2 x i64> [[TMP13]], ptr [[TMP15]], i32 8, <vscale x 2 x i1> [[ACTIVE_LANE_MASK]])
 ; TFA_INTERLEAVE-NEXT:    call void @llvm.masked.store.nxv2i64.p0(<vscale x 2 x i64> [[TMP14]], ptr [[TMP18]], i32 8, <vscale x 2 x i1> [[ACTIVE_LANE_MASK2]])
-; TFA_INTERLEAVE-NEXT:    [[INDEX_NEXT:%.*]] = add i64 [[INDEX]], [[TMP6]]
-; TFA_INTERLEAVE-NEXT:    [[INDEX_NEXT4]] = add i64 [[INDEX]], [[TMP6]]
+; TFA_INTERLEAVE-NEXT:    [[INDEX_NEXT]] = add i64 [[INDEX]], [[TMP6]]
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ayalz wrote:

Only implication visible in existing tests below is cse'ing of the Canonical IV bump when active lane masks are used. Would other test(s) be relevant?

https://github.com/llvm/llvm-project/pull/80271