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1; REQUIRES: asserts2; RUN: opt -passes='print<access-info>' -debug-only=loop-accesses -disable-output < %s 2>&1 | FileCheck %s3 4; void negative_step(int *A) {5; for (int i = 1022; i >= 0; i--)6; A[i+1] = A[i] + 1;7; }8 9; CHECK-LABEL: 'negative_step'10; CHECK: LAA: Found an analyzable loop: loop11; CHECK: LAA: Checking memory dependencies12; CHECK-NEXT: LAA: Src Scev: {(4092 + %A),+,-4}<nw><%loop>Sink Scev: {(4088 + %A)<nuw>,+,-4}<nw><%loop>13; CHECK-NEXT: LAA: Distance for store i32 %add, ptr %gep.A.plus.1, align 4 to %l = load i32, ptr %gep.A, align 4: -414; CHECK-NEXT: LAA: Src induction step: -1 Sink induction step: -115; CHECK-NEXT: LAA: Dependence is negative16 17define void @negative_step(ptr nocapture %A) {18entry:19 %A.plus.1 = getelementptr i32, ptr %A, i64 120 br label %loop21 22loop:23 %iv = phi i64 [ 1022, %entry ], [ %iv.next, %loop ]24 %gep.A = getelementptr inbounds i32, ptr %A, i64 %iv25 %l = load i32, ptr %gep.A, align 426 %add = add nsw i32 %l, 127 %gep.A.plus.1 = getelementptr i32, ptr %A.plus.1, i64 %iv28 store i32 %add, ptr %gep.A.plus.1, align 429 %iv.next = add nsw i64 %iv, -130 %cmp.not = icmp eq i64 %iv, 031 br i1 %cmp.not, label %exit, label %loop32 33exit:34 ret void35}36 37; void positive_step(int *A) {38; for (int i = 1; i < 1024; i++)39; A[i-1] = A[i] + 1;40; }41 42; CHECK-LABEL: 'positive_step'43; CHECK: LAA: Found an analyzable loop: loop44; CHECK: LAA: Checking memory dependencies45; CHECK-NEXT: LAA: Src Scev: {(4 + %A)<nuw>,+,4}<nuw><%loop>Sink Scev: {%A,+,4}<nw><%loop>46; CHECK-NEXT: LAA: Distance for %l = load i32, ptr %gep.A, align 4 to store i32 %add, ptr %gep.A.minus.1, align 4: -447; CHECK-NEXT: LAA: Src induction step: 1 Sink induction step: 148; CHECK-NEXT: LAA: Dependence is negative49 50define void @positive_step(ptr nocapture %A) {51entry:52 %A.minus.1 = getelementptr i32, ptr %A, i64 -153 br label %loop54 55loop:56 %iv = phi i64 [ 1, %entry ], [ %iv.next, %loop ]57 %gep.A = getelementptr inbounds i32, ptr %A, i64 %iv58 %l = load i32, ptr %gep.A, align 459 %add = add nsw i32 %l, 160 %gep.A.minus.1 = getelementptr i32, ptr %A.minus.1, i64 %iv61 store i32 %add, ptr %gep.A.minus.1, align 462 %iv.next = add nsw i64 %iv, 163 %cmp.not = icmp eq i64 %iv, 102464 br i1 %cmp.not, label %exit, label %loop65 66exit:67 ret void68}69 70