[llvm] [LV] Align debug location of the widen-phi to the original phi. (PR #120338)

[Elvis Wang via llvm-commits]

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@@ -15,8 +15,8 @@ define void @foo(ptr %h) !dbg !4 {
 ; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[FOR_COND_CLEANUP32:%.*]] ]
 ; CHECK-NEXT:    br label [[FOR_COND5_PREHEADER1:%.*]], !dbg [[DBG21]]
 ; CHECK:       for.cond5.preheader1:
-; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ zeroinitializer, [[VECTOR_BODY]] ], [ [[TMP4:%.*]], [[FOR_COND5_PREHEADER1]] ], !dbg [[DBG21]]
-; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, ptr [[H]], <4 x i64> [[VEC_PHI]], !dbg [[DBG21]]
+; CHECK-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i64> [ zeroinitializer, [[VECTOR_BODY]] ], [ [[TMP4:%.*]], [[FOR_COND5_PREHEADER1]] ]
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ElvisWang123 wrote:

I added a virtual debugLoc to the original scalar phi in this test case and added tests to make sure widen-phi has same debugLoc with the scalar counterpart.

https://github.com/llvm/llvm-project/pull/120338