; RUN: opt < %s -passes=loop-interchange -cache-line-size=64 \ ; RUN: -pass-remarks-output=%t -disable-output -loop-interchange-profitabilities=vectorize ; RUN: FileCheck -input-file %t %s @A = dso_local global [256 x [256 x float]] zeroinitializer @B = dso_local global [256 x [256 x float]] zeroinitializer @C = dso_local global [256 x [256 x float]] zeroinitializer @D = global [256 x [256 x [256 x float]]] zeroinitializer @E = global [256 x [256 x [256 x float]]] zeroinitializer ; Check that the below loops are exchanged for vectorization. ; ; for (int i = 0; i < 256; i++) { ; for (int j = 1; j < 256; j++) { ; A[i][j] = A[i][j-1] + B[i][j]; ; C[i][j] += 1; ; } ; } ; ; CHECK: --- !Passed ; CHECK-NEXT: Pass: loop-interchange ; CHECK-NEXT: Name: Interchanged ; CHECK-NEXT: Function: interchange_necessary_for_vectorization ; CHECK-NEXT: Args: ; CHECK-NEXT: - String: Loop interchanged with enclosing loop. define void @interchange_necessary_for_vectorization() { entry: br label %for.i.header for.i.header: %i = phi i64 [ 1, %entry ], [ %i.next, %for.i.inc ] br label %for.j.body for.j.body: %j = phi i64 [ 1, %for.i.header ], [ %j.next, %for.j.body ] %j.dec = add nsw i64 %j, -1 %a.load.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j.dec %b.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @B, i64 0, i64 %i, i64 %j %c.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @C, i64 0, i64 %i, i64 %j %a = load float, ptr %a.load.index, align 4 %b = load float, ptr %b.index, align 4 %c = load float, ptr %c.index, align 4 %add.0 = fadd float %a, %b %a.store.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j store float %add.0, ptr %a.store.index, align 4 %add.1 = fadd float %c, 1.0 store float %add.1, ptr %c.index, align 4 %j.next = add nuw nsw i64 %j, 1 %cmp.j = icmp eq i64 %j.next, 256 br i1 %cmp.j, label %for.i.inc, label %for.j.body for.i.inc: %i.next = add nuw nsw i64 %i, 1 %cmp.i = icmp eq i64 %i.next, 256 br i1 %cmp.i, label %exit, label %for.i.header exit: ret void } ; Check that the following innermost loop can be vectorized so that ; interchanging is unnecessary. ; ; for (int i = 0; i < 256; i++) ; for (int j = 1; j < 256; j++) ; A[i][j-1] = A[i][j] + B[i][j]; ; ; CHECK: --- !Missed ; CHECK-NEXT: Pass: loop-interchange ; CHECK-NEXT: Name: InterchangeNotProfitable ; CHECK-NEXT: Function: interchange_unnecesasry_for_vectorization ; CHECK-NEXT: Args: ; CHECK-NEXT: - String: Insufficient information to calculate the cost of loop for interchange. define void @interchange_unnecesasry_for_vectorization() { entry: br label %for.i.header for.i.header: %i = phi i64 [ 1, %entry ], [ %i.next, %for.i.inc ] br label %for.j.body for.j.body: %j = phi i64 [ 1, %for.i.header ], [ %j.next, %for.j.body ] %j.dec = add nsw i64 %j, -1 %a.load.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j %b.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @B, i64 0, i64 %i, i64 %j %a = load float, ptr %a.load.index, align 4 %b = load float, ptr %b.index, align 4 %add = fadd float %a, %b %a.store.index = getelementptr nuw inbounds [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j.dec store float %add, ptr %a.store.index, align 4 %j.next = add nuw nsw i64 %j, 1 %cmp.j = icmp eq i64 %j.next, 256 br i1 %cmp.j, label %for.i.inc, label %for.j.body for.i.inc: %i.next = add nuw nsw i64 %i, 1 %cmp.i = icmp eq i64 %i.next, 256 br i1 %cmp.i, label %exit, label %for.i.header exit: ret void } ; Check that the below loops are exchanged to allow innermost loop ; vectorization. We cannot vectorize the j-loop because it has a lexically ; backward dependency, but the i-loop can be vectorized because all the ; loop-carried dependencies are lexically forward. LoopVectorize currently only ; vectorizes innermost loop, hence move the i-loop to that position. ; ; for (int i = 0; i < 255; i++) { ; for (int j = 1; j < 256; j++) { ; A[i][j] = A[i][j-1] + B[i][j]; ; C[i][j] += C[i+1][j]; ; } ; } ; ; CHECK: --- !Passed ; CHECK-NEXT: Pass: loop-interchange ; CHECK-NEXT: Name: Interchanged ; CHECK-NEXT: Function: interchange_necessary_for_vectorization2 ; CHECK-NEXT: Args: ; CHECK-NEXT: - String: Loop interchanged with enclosing loop. define void @interchange_necessary_for_vectorization2() { entry: br label %for.i.header for.i.header: %i = phi i64 [ 1, %entry ], [ %i.next, %for.i.inc ] %i.inc = add i64 %i, 1 br label %for.j.body for.j.body: %j = phi i64 [ 1, %for.i.header ], [ %j.next, %for.j.body ] %j.dec = add i64 %j, -1 %a.load.index = getelementptr [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j.dec %b.index = getelementptr [256 x [256 x float]], ptr @B, i64 0, i64 %i, i64 %j %c.load.index = getelementptr [256 x [256 x float]], ptr @C, i64 0, i64 %i.inc, i64 %j %c.store.index = getelementptr [256 x [256 x float]], ptr @C, i64 0, i64 %i, i64 %j %a = load float, ptr %a.load.index %b = load float, ptr %b.index %c0 = load float, ptr %c.load.index %c1 = load float, ptr %c.store.index %add.0 = fadd float %a, %b %a.store.index = getelementptr [256 x [256 x float]], ptr @A, i64 0, i64 %i, i64 %j store float %add.0, ptr %a.store.index %add.1 = fadd float %c0, %c1 store float %add.1, ptr %c.store.index %j.next = add i64 %j, 1 %cmp.j = icmp eq i64 %j.next, 256 br i1 %cmp.j, label %for.i.inc, label %for.j.body for.i.inc: %i.next = add i64 %i, 1 %cmp.i = icmp eq i64 %i.next, 255 br i1 %cmp.i, label %exit, label %for.i.header exit: ret void } ; Check that no interchange is performed for the following loop. Interchanging ; the j-loop and k-loop makes the innermost loop vectorizble, since the j-loop ; has only forward dependencies. However, at the moment, a loop body consisting ; of multiple BBs is handled pesimistically. Hence the j-loop isn't moved to ; the innermost place. ; ; for (int i = 0; i < 255; i++) { ; for (int j = 0; j < 255; j++) { ; for (int k = 0; k < 128; k++) { ; E[i][j][k] = D[i+1][j+1][2*k]; ; if (cond) ; D[i][j][k+1] = 1.0; ; } ; } ; CHECK: --- !Missed ; CHECK-NEXT: Pass: loop-interchange ; CHECK-NEXT: Name: InterchangeNotProfitable ; CHECK-NEXT: Function: multiple_BBs_in_loop ; CHECK-NEXT: Args: ; CHECK-NEXT: - String: Interchanging loops is not considered to improve cache locality nor vectorization. ; CHECK: --- !Missed ; CHECK-NEXT: Pass: loop-interchange ; CHECK-NEXT: Name: InterchangeNotProfitable ; CHECK-NEXT: Function: multiple_BBs_in_loop ; CHECK-NEXT: Args: ; CHECK-NEXT: - String: Interchanging loops is not considered to improve cache locality nor vectorization. define void @multiple_BBs_in_loop() { entry: br label %for.i.header for.i.header: %i = phi i64 [ 0, %entry ], [ %i.inc, %for.i.inc ] %i.inc = add i64 %i, 1 br label %for.j.header for.j.header: %j = phi i64 [ 0, %for.i.header ], [ %j.inc, %for.j.inc ] %j.inc = add i64 %j, 1 br label %for.k.body for.k.body: %k = phi i64 [ 0, %for.j.header ], [ %k.inc, %for.k.inc ] %k.inc = add i64 %k, 1 %k.2 = mul i64 %k, 2 %d.index = getelementptr [256 x [256 x [256 x float]]], ptr @D, i64 0, i64 %i.inc, i64 %j.inc, i64 %k.2 %e.index = getelementptr [256 x [256 x [256 x float]]], ptr @E, i64 0, i64 %i, i64 %j, i64 %k %d.load = load float, ptr %d.index store float %d.load, ptr %e.index %cond = freeze i1 undef br i1 %cond, label %if.then, label %for.k.inc if.then: %d.index2 = getelementptr [256 x [256 x [256 x float]]], ptr @D, i64 0, i64 %i, i64 %j, i64 %k.inc store float 1.0, ptr %d.index2 br label %for.k.inc for.k.inc: %cmp.k = icmp eq i64 %k.inc, 128 br i1 %cmp.k, label %for.j.inc, label %for.k.body for.j.inc: %cmp.j = icmp eq i64 %j.inc, 255 br i1 %cmp.j, label %for.i.inc, label %for.j.header for.i.inc: %cmp.i = icmp eq i64 %i.inc, 255 br i1 %cmp.i, label %exit, label %for.i.header exit: ret void }