[llvm] [WIP][VPlan] Use BlockFrequencyInfo in getPredBlockCostDivisor (PR #158690)

[Luke Lau via llvm-commits]

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@@ -362,50 +362,17 @@ define dso_local void @test(ptr noalias nocapture %points, ptr noalias nocapture
 ; ENABLED_MASKED_STRIDED-NEXT:  entry:
 ; ENABLED_MASKED_STRIDED-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; ENABLED_MASKED_STRIDED:       vector.body:
-; ENABLED_MASKED_STRIDED-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INDEX_NEXT:%.*]], [[PRED_STORE_CONTINUE6:%.*]] ]
-; ENABLED_MASKED_STRIDED-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, [[ENTRY]] ], [ [[VEC_IND_NEXT:%.*]], [[PRED_STORE_CONTINUE6]] ]
+; ENABLED_MASKED_STRIDED-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
 ; ENABLED_MASKED_STRIDED-NEXT:    [[TMP0:%.*]] = getelementptr inbounds i16, ptr [[X:%.*]], i64 [[INDEX]]
 ; ENABLED_MASKED_STRIDED-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i16>, ptr [[TMP0]], align 2
 ; ENABLED_MASKED_STRIDED-NEXT:    [[TMP1:%.*]] = icmp sgt <4 x i16> [[WIDE_LOAD]], zeroinitializer
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP2:%.*]] = mul nuw nsw <4 x i64> [[VEC_IND]], splat (i64 3)
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP3:%.*]] = extractelement <4 x i1> [[TMP1]], i64 0
-; ENABLED_MASKED_STRIDED-NEXT:    br i1 [[TMP3]], label [[PRED_STORE_IF:%.*]], label [[PRED_STORE_CONTINUE:%.*]]
-; ENABLED_MASKED_STRIDED:       pred.store.if:
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP4:%.*]] = extractelement <4 x i64> [[TMP2]], i64 0
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP5:%.*]] = getelementptr inbounds nuw i16, ptr [[POINTS:%.*]], i64 [[TMP4]]
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP6:%.*]] = extractelement <4 x i16> [[WIDE_LOAD]], i64 0
-; ENABLED_MASKED_STRIDED-NEXT:    store i16 [[TMP6]], ptr [[TMP5]], align 2
-; ENABLED_MASKED_STRIDED-NEXT:    br label [[PRED_STORE_CONTINUE]]
-; ENABLED_MASKED_STRIDED:       pred.store.continue:
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP7:%.*]] = extractelement <4 x i1> [[TMP1]], i64 1
-; ENABLED_MASKED_STRIDED-NEXT:    br i1 [[TMP7]], label [[PRED_STORE_IF1:%.*]], label [[PRED_STORE_CONTINUE2:%.*]]
-; ENABLED_MASKED_STRIDED:       pred.store.if1:
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP8:%.*]] = extractelement <4 x i64> [[TMP2]], i64 1
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP9:%.*]] = getelementptr inbounds nuw i16, ptr [[POINTS]], i64 [[TMP8]]
-; ENABLED_MASKED_STRIDED-NEXT:    [[TMP10:%.*]] = extractelement <4 x i16> [[WIDE_LOAD]], i64 1
-; ENABLED_MASKED_STRIDED-NEXT:    store i16 [[TMP10]], ptr [[TMP9]], align 2
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lukel97 wrote:

Predication due to tail folding no longer accidentally discounts

https://github.com/llvm/llvm-project/pull/158690