[llvm] [VPlan] Use VPlan-based costs for all integer IVs. (PR #217766)

[Mel Chen via llvm-commits]

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@@ -581,23 +581,18 @@ define void @uniform_store_of_loop_varying(ptr noalias nocapture %a, ptr noalias
 ; FIXEDLEN-NEXT:  [[ENTRY:.*:]]
 ; FIXEDLEN-NEXT:    br label %[[VECTOR_PH:.*]]
 ; FIXEDLEN:       [[VECTOR_PH]]:
-; FIXEDLEN-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x ptr> poison, ptr [[B]], i64 0
-; FIXEDLEN-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x ptr> [[BROADCAST_SPLATINSERT]], <2 x ptr> poison, <2 x i32> zeroinitializer
-; FIXEDLEN-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <2 x i64> poison, i64 [[V]], i64 0
-; FIXEDLEN-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <2 x i64> [[BROADCAST_SPLATINSERT1]], <2 x i64> poison, <2 x i32> zeroinitializer
+; FIXEDLEN-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[V]], i64 0
+; FIXEDLEN-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
 ; FIXEDLEN-NEXT:    br label %[[VECTOR_BODY:.*]]
 ; FIXEDLEN:       [[VECTOR_BODY]]:
 ; FIXEDLEN-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
-; FIXEDLEN-NEXT:    [[VEC_IND:%.*]] = phi <2 x i64> [ <i64 0, i64 1>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
-; FIXEDLEN-NEXT:    [[STEP_ADD:%.*]] = add nuw <2 x i64> [[VEC_IND]], splat (i64 2)
-; FIXEDLEN-NEXT:    call void @llvm.masked.scatter.v2i64.v2p0(<2 x i64> [[VEC_IND]], <2 x ptr> align 8 [[BROADCAST_SPLAT]], <2 x i1> splat (i1 true))
-; FIXEDLEN-NEXT:    call void @llvm.masked.scatter.v2i64.v2p0(<2 x i64> [[STEP_ADD]], <2 x ptr> align 8 [[BROADCAST_SPLAT]], <2 x i1> splat (i1 true))
+; FIXEDLEN-NEXT:    [[TMP0:%.*]] = add i64 [[INDEX]], 7
+; FIXEDLEN-NEXT:    store i64 [[TMP0]], ptr [[B]], align 8
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Mel-Chen wrote:

Good change, but how does altering the cost model address this problem?

https://github.com/llvm/llvm-project/pull/217766