[llvm] [LV]: Ensure fairness when selecting epilogue VF. (PR #155547)

[Florian Hahn via llvm-commits]

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@@ -24,30 +24,30 @@ define i32 @interleave_integer_reduction(ptr %src, i64 %N) {
 ; INTERLEAVE-4-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; INTERLEAVE-4:       vector.body:
 ; INTERLEAVE-4-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
-; INTERLEAVE-4-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP12:%.*]], [[VECTOR_BODY]] ]
-; INTERLEAVE-4-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP13:%.*]], [[VECTOR_BODY]] ]
-; INTERLEAVE-4-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP14:%.*]], [[VECTOR_BODY]] ]
-; INTERLEAVE-4-NEXT:    [[VEC_PHI4:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP15:%.*]], [[VECTOR_BODY]] ]
-; INTERLEAVE-4-NEXT:    [[TMP4:%.*]] = getelementptr inbounds i32, ptr [[SRC:%.*]], i64 [[INDEX]]
-; INTERLEAVE-4-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i32, ptr [[TMP4]], i32 4
-; INTERLEAVE-4-NEXT:    [[TMP10:%.*]] = getelementptr inbounds i32, ptr [[TMP4]], i32 8
-; INTERLEAVE-4-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i32, ptr [[TMP4]], i32 12
-; INTERLEAVE-4-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i32>, ptr [[TMP4]], align 1
-; INTERLEAVE-4-NEXT:    [[WIDE_LOAD5:%.*]] = load <4 x i32>, ptr [[TMP9]], align 1
-; INTERLEAVE-4-NEXT:    [[WIDE_LOAD6:%.*]] = load <4 x i32>, ptr [[TMP10]], align 1
-; INTERLEAVE-4-NEXT:    [[WIDE_LOAD7:%.*]] = load <4 x i32>, ptr [[TMP11]], align 1
-; INTERLEAVE-4-NEXT:    [[TMP12]] = add <4 x i32> [[VEC_PHI]], [[WIDE_LOAD]]
-; INTERLEAVE-4-NEXT:    [[TMP13]] = add <4 x i32> [[VEC_PHI2]], [[WIDE_LOAD5]]
-; INTERLEAVE-4-NEXT:    [[TMP14]] = add <4 x i32> [[VEC_PHI3]], [[WIDE_LOAD6]]
-; INTERLEAVE-4-NEXT:    [[TMP15]] = add <4 x i32> [[VEC_PHI4]], [[WIDE_LOAD7]]
+; INTERLEAVE-4-NEXT:    [[VEC_PHI:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP4:%.*]], [[VECTOR_BODY]] ]
+; INTERLEAVE-4-NEXT:    [[VEC_PHI2:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP5:%.*]], [[VECTOR_BODY]] ]
+; INTERLEAVE-4-NEXT:    [[VEC_PHI3:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP6:%.*]], [[VECTOR_BODY]] ]
+; INTERLEAVE-4-NEXT:    [[VEC_PHI4:%.*]] = phi <4 x i32> [ zeroinitializer, [[VECTOR_PH]] ], [ [[TMP7:%.*]], [[VECTOR_BODY]] ]
+; INTERLEAVE-4-NEXT:    [[TMP0:%.*]] = getelementptr inbounds i32, ptr [[SRC:%.*]], i64 [[INDEX]]
+; INTERLEAVE-4-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, ptr [[TMP0]], i32 4
+; INTERLEAVE-4-NEXT:    [[TMP2:%.*]] = getelementptr inbounds i32, ptr [[TMP0]], i32 8
+; INTERLEAVE-4-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i32, ptr [[TMP0]], i32 12
+; INTERLEAVE-4-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x i32>, ptr [[TMP0]], align 1
+; INTERLEAVE-4-NEXT:    [[WIDE_LOAD5:%.*]] = load <4 x i32>, ptr [[TMP1]], align 1
+; INTERLEAVE-4-NEXT:    [[WIDE_LOAD6:%.*]] = load <4 x i32>, ptr [[TMP2]], align 1
+; INTERLEAVE-4-NEXT:    [[WIDE_LOAD7:%.*]] = load <4 x i32>, ptr [[TMP3]], align 1
+; INTERLEAVE-4-NEXT:    [[TMP4]] = add <4 x i32> [[VEC_PHI]], [[WIDE_LOAD]]
+; INTERLEAVE-4-NEXT:    [[TMP5]] = add <4 x i32> [[VEC_PHI2]], [[WIDE_LOAD5]]
+; INTERLEAVE-4-NEXT:    [[TMP6]] = add <4 x i32> [[VEC_PHI3]], [[WIDE_LOAD6]]
+; INTERLEAVE-4-NEXT:    [[TMP7]] = add <4 x i32> [[VEC_PHI4]], [[WIDE_LOAD7]]
 ; INTERLEAVE-4-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 16
-; INTERLEAVE-4-NEXT:    [[TMP16:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
-; INTERLEAVE-4-NEXT:    br i1 [[TMP16]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; INTERLEAVE-4-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
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fhahn wrote:

The changes here and a few below look to be just renaming, could you strip those from the patch so it's easier to see what the impact of the change is?

https://github.com/llvm/llvm-project/pull/155547