[llvm] [VPlan] Update scalar induction resume values in VPlan. (PR #110577)

[via llvm-commits]

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@@ -50,6 +51,7 @@ define void @test_widen_ptr_induction(ptr %ptr.start.1) {
 ; CHECK-NEXT:    br i1 true, label [[VEC_EPILOG_SCALAR_PH]], label [[VEC_EPILOG_PH]]
 ; CHECK:       vec.epilog.ph:
 ; CHECK-NEXT:    [[VEC_EPILOG_RESUME_VAL:%.*]] = phi i64 [ 10000, [[VEC_EPILOG_ITER_CHECK]] ], [ 0, [[VECTOR_MAIN_LOOP_ITER_CHECK]] ]
+; CHECK-NEXT:    [[BC_RESUME_VAL4:%.*]] = phi ptr [ [[IND_END1]], [[VEC_EPILOG_ITER_CHECK]] ], [ [[PTR_START_1]], [[VECTOR_MAIN_LOOP_ITER_CHECK]] ]
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ayalz wrote:

This appears unused, subject to dce. Is it possibly to avoid introducing such redundant phi's, and transitively IND_END1 which feeds them (only), to reduce test differences?

https://github.com/llvm/llvm-project/pull/110577