; REQUIRES: asserts ; RUN: opt < %s -basic-aa -loop-interchange -cache-line-size=64 -verify-dom-info -verify-loop-info \ ; RUN: -S -debug 2>&1 | FileCheck %s target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" @A = common global [100 x [100 x i32]] zeroinitializer @B = common global [100 x i32] zeroinitializer @C = common global [100 x [100 x i32]] zeroinitializer @D = common global [100 x [100 x [100 x i32]]] zeroinitializer ;; Loops not tightly nested are not interchanged ;; for(int j=0;j<N;j++) { ;; B[j] = j+k; ;; for(int i=0;i<N;i++) ;; A[j][i] = A[j][i]+B[j]; ;; } ; CHECK: Not interchanging loops. Cannot prove legality. define void @interchange_05(i32 %k, i32 %N){ entry: %cmp30 = icmp sgt i32 %N, 0 br i1 %cmp30, label %for.body.lr.ph, label %for.end17 for.body.lr.ph: %0 = add i32 %N, -1 %1 = zext i32 %k to i64 br label %for.body for.body: %indvars.iv32 = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next33, %for.inc15 ] %2 = add nsw i64 %indvars.iv32, %1 %arrayidx = getelementptr inbounds [100 x i32], [100 x i32]* @B, i64 0, i64 %indvars.iv32 %3 = trunc i64 %2 to i32 store i32 %3, i32* %arrayidx br label %for.body3 for.body3: %indvars.iv = phi i64 [ 0, %for.body ], [ %indvars.iv.next, %for.body3 ] %arrayidx7 = getelementptr inbounds [100 x [100 x i32]], [100 x [100 x i32]]* @A, i64 0, i64 %indvars.iv32, i64 %indvars.iv %4 = load i32, i32* %arrayidx7 %add10 = add nsw i32 %3, %4 store i32 %add10, i32* %arrayidx7 %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 %lftr.wideiv = trunc i64 %indvars.iv to i32 %exitcond = icmp eq i32 %lftr.wideiv, %0 br i1 %exitcond, label %for.inc15, label %for.body3 for.inc15: %indvars.iv.next33 = add nuw nsw i64 %indvars.iv32, 1 %lftr.wideiv35 = trunc i64 %indvars.iv32 to i32 %exitcond36 = icmp eq i32 %lftr.wideiv35, %0 br i1 %exitcond36, label %for.end17, label %for.body for.end17: ret void } declare void @foo(...) readnone ;; Loops not tightly nested are not interchanged ;; for(int j=0;j<N;j++) { ;; foo(); ;; for(int i=2;i<N;i++) ;; A[j][i] = A[j][i]+k; ;; } ; CHECK: Not interchanging loops. Cannot prove legality. define void @interchange_06(i32 %k, i32 %N) { entry: %cmp22 = icmp sgt i32 %N, 0 br i1 %cmp22, label %for.body.lr.ph, label %for.end12 for.body.lr.ph: %0 = add i32 %N, -1 br label %for.body for.body: %indvars.iv24 = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next25, %for.inc10 ] tail call void (...) @foo() br label %for.body3 for.body3: %indvars.iv = phi i64 [ %indvars.iv.next, %for.body3 ], [ 2, %for.body ] %arrayidx5 = getelementptr inbounds [100 x [100 x i32]], [100 x [100 x i32]]* @A, i64 0, i64 %indvars.iv24, i64 %indvars.iv %1 = load i32, i32* %arrayidx5 %add = add nsw i32 %1, %k store i32 %add, i32* %arrayidx5 %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 %lftr.wideiv = trunc i64 %indvars.iv to i32 %exitcond = icmp eq i32 %lftr.wideiv, %0 br i1 %exitcond, label %for.inc10, label %for.body3 for.inc10: %indvars.iv.next25 = add nuw nsw i64 %indvars.iv24, 1 %lftr.wideiv26 = trunc i64 %indvars.iv24 to i32 %exitcond27 = icmp eq i32 %lftr.wideiv26, %0 br i1 %exitcond27, label %for.end12, label %for.body for.end12: ret void } ;; The following Loop is not considered tightly nested and is not interchanged. ;; The outer loop header does not branch to the inner loop preheader, or the ;; inner loop header, or the outer loop latch. ; CHECK: Not interchanging loops. Cannot prove legality. define void @interchange_07(i32 %k, i32 %N, i64 %ny) { entry: br label %for1.header for1.header: %j23 = phi i64 [ 0, %entry ], [ %j.next24, %for1.inc10 ] %cmp21 = icmp slt i64 0, %ny br label %singleSucc singleSucc: br i1 %cmp21, label %preheader.j, label %for1.inc10 preheader.j: br label %for2 for2: %j = phi i64 [ %j.next, %for2 ], [ 0, %preheader.j ] %arrayidx5 = getelementptr inbounds [100 x [100 x i32]], [100 x [100 x i32]]* @A, i64 0, i64 %j, i64 %j23 %lv = load i32, i32* %arrayidx5 %add = add nsw i32 %lv, %k store i32 %add, i32* %arrayidx5 %j.next = add nuw nsw i64 %j, 1 %exitcond = icmp eq i64 %j, 99 br i1 %exitcond, label %for1.inc10, label %for2 for1.inc10: %j.next24 = add nuw nsw i64 %j23, 1 %exitcond26 = icmp eq i64 %j23, 99 br i1 %exitcond26, label %for.end12, label %for1.header for.end12: ret void }