[SLP][NFC] Add test case exposing deficiency in finding reductions that feed buildvector sequence.

Differential Revision: https://reviews.llvm.org/D132506

Author: Valery N Dmitriev

llvm/test/Transforms/SLPVectorizer/X86/redux-feed-buildvector.ll

@@ -0,0 +1,194 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -mtriple=x86_64 -slp-vectorizer -S -mcpu=skylake-avx512 | FileCheck %s
+
+; The test represents the case with multiple vectorization possibilities
+; but the most effective way to vectorize it is to match both 8-way reductions
+; feeding the insertelement vector build sequence.
+
+declare void @llvm.masked.scatter.v2f64.v2p0f64(<2 x double>, <2 x double*>, i32 immarg, <2 x i1>)
+
+define void @test(double* nocapture readonly %arg, double* nocapture readonly %arg1, double* nocapture %arg2) {
+; CHECK-LABEL: @test(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[GEP1_0:%.*]] = getelementptr inbounds double, double* [[ARG:%.*]], i64 1
+; CHECK-NEXT:    [[LD1_0:%.*]] = load double, double* [[GEP1_0]], align 8
+; CHECK-NEXT:    [[GEP2_0:%.*]] = getelementptr inbounds double, double* [[ARG1:%.*]], i64 16
+; CHECK-NEXT:    [[GEP1_1:%.*]] = getelementptr inbounds double, double* [[ARG]], i64 3
+; CHECK-NEXT:    [[LD1_1:%.*]] = load double, double* [[GEP1_1]], align 8
+; CHECK-NEXT:    [[GEP0_1:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 1
+; CHECK-NEXT:    [[GEP2_1:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 17
+; CHECK-NEXT:    [[GEP1_2:%.*]] = getelementptr inbounds double, double* [[ARG]], i64 5
+; CHECK-NEXT:    [[LD1_2:%.*]] = load double, double* [[GEP1_2]], align 8
+; CHECK-NEXT:    [[GEP0_2:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 2
+; CHECK-NEXT:    [[GEP2_2:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 18
+; CHECK-NEXT:    [[GEP1_3:%.*]] = getelementptr inbounds double, double* [[ARG]], i64 7
+; CHECK-NEXT:    [[LD1_3:%.*]] = load double, double* [[GEP1_3]], align 8
+; CHECK-NEXT:    [[GEP0_3:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 3
+; CHECK-NEXT:    [[GEP2_3:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 19
+; CHECK-NEXT:    [[GEP1_4:%.*]] = getelementptr inbounds double, double* [[ARG]], i64 9
+; CHECK-NEXT:    [[LD1_4:%.*]] = load double, double* [[GEP1_4]], align 8
+; CHECK-NEXT:    [[GEP0_4:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 4
+; CHECK-NEXT:    [[GEP2_4:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 20
+; CHECK-NEXT:    [[GEP1_5:%.*]] = getelementptr inbounds double, double* [[ARG]], i64 11
+; CHECK-NEXT:    [[LD1_5:%.*]] = load double, double* [[GEP1_5]], align 8
+; CHECK-NEXT:    [[GEP0_5:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 5
+; CHECK-NEXT:    [[GEP2_5:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 21
+; CHECK-NEXT:    [[GEP1_6:%.*]] = getelementptr inbounds double, double* [[ARG]], i64 13
+; CHECK-NEXT:    [[LD1_6:%.*]] = load double, double* [[GEP1_6]], align 8
+; CHECK-NEXT:    [[GEP0_6:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 6
+; CHECK-NEXT:    [[GEP2_6:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 22
+; CHECK-NEXT:    [[GEP1_7:%.*]] = getelementptr inbounds double, double* [[ARG]], i64 15
+; CHECK-NEXT:    [[LD1_7:%.*]] = load double, double* [[GEP1_7]], align 8
+; CHECK-NEXT:    [[GEP0_7:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 7
+; CHECK-NEXT:    [[GEP2_7:%.*]] = getelementptr inbounds double, double* [[ARG1]], i64 23
+; CHECK-NEXT:    [[LD0_0:%.*]] = load double, double* [[ARG1]], align 8
+; CHECK-NEXT:    [[LD2_0:%.*]] = load double, double* [[GEP2_0]], align 8
+; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <2 x double> poison, double [[LD0_0]], i32 0
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <2 x double> [[TMP0]], double [[LD2_0]], i32 1
+; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <2 x double> poison, double [[LD1_0]], i32 0
+; CHECK-NEXT:    [[TMP3:%.*]] = insertelement <2 x double> [[TMP2]], double [[LD1_0]], i32 1
+; CHECK-NEXT:    [[TMP4:%.*]] = fmul fast <2 x double> [[TMP1]], [[TMP3]]
+; CHECK-NEXT:    [[LD0_1:%.*]] = load double, double* [[GEP0_1]], align 8
+; CHECK-NEXT:    [[LD2_1:%.*]] = load double, double* [[GEP2_1]], align 8
+; CHECK-NEXT:    [[TMP5:%.*]] = insertelement <2 x double> poison, double [[LD0_1]], i32 0
+; CHECK-NEXT:    [[TMP6:%.*]] = insertelement <2 x double> [[TMP5]], double [[LD2_1]], i32 1
+; CHECK-NEXT:    [[TMP7:%.*]] = insertelement <2 x double> poison, double [[LD1_1]], i32 0
+; CHECK-NEXT:    [[TMP8:%.*]] = insertelement <2 x double> [[TMP7]], double [[LD1_1]], i32 1
+; CHECK-NEXT:    [[TMP9:%.*]] = fmul fast <2 x double> [[TMP6]], [[TMP8]]
+; CHECK-NEXT:    [[TMP10:%.*]] = fadd fast <2 x double> [[TMP4]], [[TMP9]]
+; CHECK-NEXT:    [[LD0_2:%.*]] = load double, double* [[GEP0_2]], align 8
+; CHECK-NEXT:    [[LD2_2:%.*]] = load double, double* [[GEP2_2]], align 8
+; CHECK-NEXT:    [[TMP11:%.*]] = insertelement <2 x double> poison, double [[LD0_2]], i32 0
+; CHECK-NEXT:    [[TMP12:%.*]] = insertelement <2 x double> [[TMP11]], double [[LD2_2]], i32 1
+; CHECK-NEXT:    [[TMP13:%.*]] = insertelement <2 x double> poison, double [[LD1_2]], i32 0
+; CHECK-NEXT:    [[TMP14:%.*]] = insertelement <2 x double> [[TMP13]], double [[LD1_2]], i32 1
+; CHECK-NEXT:    [[TMP15:%.*]] = fmul fast <2 x double> [[TMP12]], [[TMP14]]
+; CHECK-NEXT:    [[TMP16:%.*]] = fadd fast <2 x double> [[TMP10]], [[TMP15]]
+; CHECK-NEXT:    [[LD0_3:%.*]] = load double, double* [[GEP0_3]], align 8
+; CHECK-NEXT:    [[LD2_3:%.*]] = load double, double* [[GEP2_3]], align 8
+; CHECK-NEXT:    [[TMP17:%.*]] = insertelement <2 x double> poison, double [[LD0_3]], i32 0
+; CHECK-NEXT:    [[TMP18:%.*]] = insertelement <2 x double> [[TMP17]], double [[LD2_3]], i32 1
+; CHECK-NEXT:    [[TMP19:%.*]] = insertelement <2 x double> poison, double [[LD1_3]], i32 0
+; CHECK-NEXT:    [[TMP20:%.*]] = insertelement <2 x double> [[TMP19]], double [[LD1_3]], i32 1
+; CHECK-NEXT:    [[TMP21:%.*]] = fmul fast <2 x double> [[TMP18]], [[TMP20]]
+; CHECK-NEXT:    [[TMP22:%.*]] = fadd fast <2 x double> [[TMP16]], [[TMP21]]
+; CHECK-NEXT:    [[LD0_4:%.*]] = load double, double* [[GEP0_4]], align 8
+; CHECK-NEXT:    [[LD2_4:%.*]] = load double, double* [[GEP2_4]], align 8
+; CHECK-NEXT:    [[TMP23:%.*]] = insertelement <2 x double> poison, double [[LD0_4]], i32 0
+; CHECK-NEXT:    [[TMP24:%.*]] = insertelement <2 x double> [[TMP23]], double [[LD2_4]], i32 1
+; CHECK-NEXT:    [[TMP25:%.*]] = insertelement <2 x double> poison, double [[LD1_4]], i32 0
+; CHECK-NEXT:    [[TMP26:%.*]] = insertelement <2 x double> [[TMP25]], double [[LD1_4]], i32 1
+; CHECK-NEXT:    [[TMP27:%.*]] = fmul fast <2 x double> [[TMP24]], [[TMP26]]
+; CHECK-NEXT:    [[TMP28:%.*]] = fadd fast <2 x double> [[TMP22]], [[TMP27]]
+; CHECK-NEXT:    [[LD0_5:%.*]] = load double, double* [[GEP0_5]], align 8
+; CHECK-NEXT:    [[LD2_5:%.*]] = load double, double* [[GEP2_5]], align 8
+; CHECK-NEXT:    [[TMP29:%.*]] = insertelement <2 x double> poison, double [[LD0_5]], i32 0
+; CHECK-NEXT:    [[TMP30:%.*]] = insertelement <2 x double> [[TMP29]], double [[LD2_5]], i32 1
+; CHECK-NEXT:    [[TMP31:%.*]] = insertelement <2 x double> poison, double [[LD1_5]], i32 0
+; CHECK-NEXT:    [[TMP32:%.*]] = insertelement <2 x double> [[TMP31]], double [[LD1_5]], i32 1
+; CHECK-NEXT:    [[TMP33:%.*]] = fmul fast <2 x double> [[TMP30]], [[TMP32]]
+; CHECK-NEXT:    [[TMP34:%.*]] = fadd fast <2 x double> [[TMP28]], [[TMP33]]
+; CHECK-NEXT:    [[LD0_6:%.*]] = load double, double* [[GEP0_6]], align 8
+; CHECK-NEXT:    [[LD2_6:%.*]] = load double, double* [[GEP2_6]], align 8
+; CHECK-NEXT:    [[TMP35:%.*]] = insertelement <2 x double> poison, double [[LD0_6]], i32 0
+; CHECK-NEXT:    [[TMP36:%.*]] = insertelement <2 x double> [[TMP35]], double [[LD2_6]], i32 1
+; CHECK-NEXT:    [[TMP37:%.*]] = insertelement <2 x double> poison, double [[LD1_6]], i32 0
+; CHECK-NEXT:    [[TMP38:%.*]] = insertelement <2 x double> [[TMP37]], double [[LD1_6]], i32 1
+; CHECK-NEXT:    [[TMP39:%.*]] = fmul fast <2 x double> [[TMP36]], [[TMP38]]
+; CHECK-NEXT:    [[TMP40:%.*]] = fadd fast <2 x double> [[TMP34]], [[TMP39]]
+; CHECK-NEXT:    [[LD0_7:%.*]] = load double, double* [[GEP0_7]], align 8
+; CHECK-NEXT:    [[LD2_7:%.*]] = load double, double* [[GEP2_7]], align 8
+; CHECK-NEXT:    [[TMP41:%.*]] = insertelement <2 x double> poison, double [[LD0_7]], i32 0
+; CHECK-NEXT:    [[TMP42:%.*]] = insertelement <2 x double> [[TMP41]], double [[LD2_7]], i32 1
+; CHECK-NEXT:    [[TMP43:%.*]] = insertelement <2 x double> poison, double [[LD1_7]], i32 0
+; CHECK-NEXT:    [[TMP44:%.*]] = insertelement <2 x double> [[TMP43]], double [[LD1_7]], i32 1
+; CHECK-NEXT:    [[TMP45:%.*]] = fmul fast <2 x double> [[TMP42]], [[TMP44]]
+; CHECK-NEXT:    [[TMP46:%.*]] = fadd fast <2 x double> [[TMP40]], [[TMP45]]
+; CHECK-NEXT:    [[P:%.*]] = getelementptr inbounds double, double* [[ARG2:%.*]], <2 x i64> <i64 0, i64 16>
+; CHECK-NEXT:    call void @llvm.masked.scatter.v2f64.v2p0f64(<2 x double> [[TMP46]], <2 x double*> [[P]], i32 8, <2 x i1> <i1 true, i1 true>)
+; CHECK-NEXT:    ret void
+;
+entry:
+  %gep1.0 = getelementptr inbounds double, double* %arg, i64 1
+  %ld1.0 = load double, double* %gep1.0, align 8
+  %ld0.0 = load double, double* %arg1, align 8
+  %mul1.0 = fmul fast double %ld0.0, %ld1.0
+  %gep2.0 = getelementptr inbounds double, double* %arg1, i64 16
+  %ld2.0 = load double, double* %gep2.0, align 8
+  %mul2.0 = fmul fast double %ld2.0, %ld1.0
+  %gep1.1 = getelementptr inbounds double, double* %arg, i64 3
+  %ld1.1 = load double, double* %gep1.1, align 8
+  %gep0.1 = getelementptr inbounds double, double* %arg1, i64 1
+  %ld0.1 = load double, double* %gep0.1, align 8
+  %mul1.1 = fmul fast double %ld0.1, %ld1.1
+  %rdx1.0 = fadd fast double %mul1.0, %mul1.1
+  %gep2.1 = getelementptr inbounds double, double* %arg1, i64 17
+  %ld2.1 = load double, double* %gep2.1, align 8
+  %mul2.1 = fmul fast double %ld2.1, %ld1.1
+  %rdx2.0 = fadd fast double %mul2.0, %mul2.1
+  %gep1.2 = getelementptr inbounds double, double* %arg, i64 5
+  %ld1.2 = load double, double* %gep1.2, align 8
+  %gep0.2 = getelementptr inbounds double, double* %arg1, i64 2
+  %ld0.2 = load double, double* %gep0.2, align 8
+  %mul1.2 = fmul fast double %ld0.2, %ld1.2
+  %rdx1.1 = fadd fast double %rdx1.0, %mul1.2
+  %gep2.2 = getelementptr inbounds double, double* %arg1, i64 18
+  %ld2.2 = load double, double* %gep2.2, align 8
+  %mul2.2 = fmul fast double %ld2.2, %ld1.2
+  %rdx2.1 = fadd fast double %rdx2.0, %mul2.2
+  %gep1.3 = getelementptr inbounds double, double* %arg, i64 7
+  %ld1.3 = load double, double* %gep1.3, align 8
+  %gep0.3 = getelementptr inbounds double, double* %arg1, i64 3
+  %ld0.3 = load double, double* %gep0.3, align 8
+  %mul1.3 = fmul fast double %ld0.3, %ld1.3
+  %rdx1.2 = fadd fast double %rdx1.1, %mul1.3
+  %gep2.3 = getelementptr inbounds double, double* %arg1, i64 19
+  %ld2.3 = load double, double* %gep2.3, align 8
+  %mul2.3 = fmul fast double %ld2.3, %ld1.3
+  %rdx2.2 = fadd fast double %rdx2.1, %mul2.3
+  %gep1.4 = getelementptr inbounds double, double* %arg, i64 9
+  %ld1.4 = load double, double* %gep1.4, align 8
+  %gep0.4 = getelementptr inbounds double, double* %arg1, i64 4
+  %ld0.4 = load double, double* %gep0.4, align 8
+  %mul1.4 = fmul fast double %ld0.4, %ld1.4
+  %rdx1.3 = fadd fast double %rdx1.2, %mul1.4
+  %gep2.4 = getelementptr inbounds double, double* %arg1, i64 20
+  %ld2.4 = load double, double* %gep2.4, align 8
+  %mul2.4 = fmul fast double %ld2.4, %ld1.4
+  %rdx2.3 = fadd fast double %rdx2.2, %mul2.4
+  %gep1.5 = getelementptr inbounds double, double* %arg, i64 11
+  %ld1.5 = load double, double* %gep1.5, align 8
+  %gep0.5 = getelementptr inbounds double, double* %arg1, i64 5
+  %ld0.5 = load double, double* %gep0.5, align 8
+  %mul1.5 = fmul fast double %ld0.5, %ld1.5
+  %rdx1.4 = fadd fast double %rdx1.3, %mul1.5
+  %gep2.5 = getelementptr inbounds double, double* %arg1, i64 21
+  %ld2.5 = load double, double* %gep2.5, align 8
+  %mul2.5 = fmul fast double %ld2.5, %ld1.5
+  %rdx2.4 = fadd fast double %rdx2.3, %mul2.5
+  %gep1.6 = getelementptr inbounds double, double* %arg, i64 13
+  %ld1.6 = load double, double* %gep1.6, align 8
+  %gep0.6 = getelementptr inbounds double, double* %arg1, i64 6
+  %ld0.6 = load double, double* %gep0.6, align 8
+  %mul1.6 = fmul fast double %ld0.6, %ld1.6
+  %rdx1.5 = fadd fast double %rdx1.4, %mul1.6
+  %gep2.6 = getelementptr inbounds double, double* %arg1, i64 22
+  %ld2.6 = load double, double* %gep2.6, align 8
+  %mul2.6 = fmul fast double %ld2.6, %ld1.6
+  %rdx2.5 = fadd fast double %rdx2.4, %mul2.6
+  %gep1.7 = getelementptr inbounds double, double* %arg, i64 15
+  %ld1.7 = load double, double* %gep1.7, align 8
+  %gep0.7 = getelementptr inbounds double, double* %arg1, i64 7
+  %ld0.7 = load double, double* %gep0.7, align 8
+  %mul1.7 = fmul fast double %ld0.7, %ld1.7
+  %rdx1 = fadd fast double %rdx1.5, %mul1.7
+  %gep2.7 = getelementptr inbounds double, double* %arg1, i64 23
+  %ld2.7 = load double, double* %gep2.7, align 8
+  %mul2.7 = fmul fast double %ld2.7, %ld1.7
+  %rdx2 = fadd fast double %rdx2.5, %mul2.7
+  %i142 = insertelement <2 x double> poison, double %rdx1, i64 0
+  %i143 = insertelement <2 x double> %i142, double %rdx2, i64 1
+  %p = getelementptr inbounds double, double* %arg2, <2 x i64> <i64 0, i64 16>
+  call void @llvm.masked.scatter.v2f64.v2p0f64(<2 x double> %i143, <2 x double*> %p, i32 8, <2 x i1> <i1 true, i1 true>)
+  ret void
+}