--- /dev/null
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -mtriple=x86_64 -mcpu=skylake-avx512 -passes=slp-vectorizer -pass-remarks-output=%t < %s | FileCheck %s
+; RUN: FileCheck --input-file=%t --check-prefix=YAML %s
+
+define i32 @test(ptr noalias %p, ptr noalias %addr) {
+; CHECK-LABEL: @test(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[TMP0:%.*]] = insertelement <8 x ptr> poison, ptr [[ADDR:%.*]], i32 0
+; CHECK-NEXT: [[TMP1:%.*]] = shufflevector <8 x ptr> [[TMP0]], <8 x ptr> poison, <8 x i32> zeroinitializer
+; CHECK-NEXT: [[TMP2:%.*]] = getelementptr i32, <8 x ptr> [[TMP1]], <8 x i32> <i32 15, i32 13, i32 11, i32 9, i32 7, i32 5, i32 3, i32 1>
+; CHECK-NEXT: [[TMP3:%.*]] = call <8 x i32> @llvm.masked.gather.v8i32.v8p0(<8 x ptr> [[TMP2]], i32 8, <8 x i1> <i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true>, <8 x i32> poison)
+; CHECK-NEXT: [[TMP4:%.*]] = insertelement <8 x ptr> poison, ptr [[P:%.*]], i32 0
+; CHECK-NEXT: [[TMP5:%.*]] = shufflevector <8 x ptr> [[TMP4]], <8 x ptr> poison, <8 x i32> zeroinitializer
+; CHECK-NEXT: [[TMP6:%.*]] = getelementptr i32, <8 x ptr> [[TMP5]], <8 x i32> [[TMP3]]
+; CHECK-NEXT: [[TMP7:%.*]] = call <8 x i32> @llvm.masked.gather.v8i32.v8p0(<8 x ptr> [[TMP6]], i32 4, <8 x i1> <i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true, i1 true>, <8 x i32> poison)
+; CHECK-NEXT: [[TMP8:%.*]] = call i32 @llvm.vector.reduce.add.v8i32(<8 x i32> [[TMP7]])
+; CHECK-NEXT: ret i32 [[TMP8]]
+;
+; YAML: --- !Passed
+ ; YAML-NEXT: Pass: slp-vectorizer
+ ; YAML-NEXT: Name: VectorizedHorizontalReduction
+ ; YAML-NEXT: Function: test
+ ; YAML-NEXT: Args:
+ ; YAML-NEXT: - String: 'Vectorized horizontal reduction with cost '
+ ; YAML-NEXT: - Cost: '-17'
+ ; YAML-NEXT: - String: ' and with tree size '
+ ; YAML-NEXT: - TreeSize: '7'
+entry:
+ %off0.1 = getelementptr inbounds i32, ptr %addr, i32 1
+ %idx0 = load i32, ptr %off0.1, align 8
+ %gep0 = getelementptr inbounds i32, ptr %p, i32 %idx0
+ %ld0 = load i32, ptr %gep0, align 4
+
+ %off1.3 = getelementptr inbounds i32, ptr %addr, i32 3
+ %idx1 = load i32, ptr %off1.3, align 8
+ %gep1 = getelementptr inbounds i32, ptr %p, i32 %idx1
+ %ld1 = load i32, ptr %gep1, align 4
+
+ %off2.5 = getelementptr inbounds i32, ptr %addr, i32 5
+ %idx2 = load i32, ptr %off2.5, align 8
+ %gep2 = getelementptr inbounds i32, ptr %p, i32 %idx2
+ %ld2 = load i32, ptr %gep2, align 4
+
+ %off3.7 = getelementptr inbounds i32, ptr %addr, i32 7
+ %idx3 = load i32, ptr %off3.7, align 8
+ %gep3 = getelementptr inbounds i32, ptr %p, i32 %idx3
+ %ld3 = load i32, ptr %gep3, align 4
+
+ %off4.9 = getelementptr inbounds i32, ptr %addr, i32 9
+ %idx4 = load i32, ptr %off4.9, align 8
+ %gep4 = getelementptr inbounds i32, ptr %p, i32 %idx4
+ %ld4 = load i32, ptr %gep4, align 4
+
+ %off5.11 = getelementptr inbounds i32, ptr %addr, i32 11
+ %idx5 = load i32, ptr %off5.11, align 8
+ %gep5 = getelementptr inbounds i32, ptr %p, i32 %idx5
+ %ld5 = load i32, ptr %gep5, align 4
+
+ %off6.13 = getelementptr inbounds i32, ptr %addr, i32 13
+ %idx6 = load i32, ptr %off6.13, align 8
+ %gep6 = getelementptr inbounds i32, ptr %p, i32 %idx6
+ %ld6 = load i32, ptr %gep6, align 4
+
+ %off7.15 = getelementptr inbounds i32, ptr %addr, i32 15
+ %idx7 = load i32, ptr %off7.15, align 8
+ %gep7 = getelementptr inbounds i32, ptr %p, i32 %idx7
+ %ld7 = load i32, ptr %gep7, align 4
+
+ %add0 = add nsw i32 %ld1, %ld0
+ %add1 = add nsw i32 %add0, %ld2
+ %add2 = add nsw i32 %add1, %ld3
+ %add3 = add nsw i32 %add2, %ld4
+ %add4 = add nsw i32 %add3, %ld5
+ %add5 = add nsw i32 %add4, %ld6
+ %add6 = add nsw i32 %add5, %ld7
+
+ ret i32 %add6
+}