|  | ; RUN: opt -S -passes=loop-simplify,loop-fusion -debug-only=loop-fusion -disable-output < %s 2>&1 | FileCheck %s | 
|  | ; REQUIRES: asserts | 
|  |  | 
|  | @B = common global [1024 x i32] zeroinitializer, align 16 | 
|  |  | 
|  | ; Check that the two candidates for fusion are placed into separate candidate | 
|  | ; sets because they are not control flow equivalent. | 
|  |  | 
|  | ; CHECK: Performing Loop Fusion on function non_cfe | 
|  | ; CHECK: Fusion Candidates: | 
|  | ; CHECK: *** Fusion Candidate Set *** | 
|  | ; CHECK: bb | 
|  | ; CHECK: **************************** | 
|  | ; CHECK: *** Fusion Candidate Set *** | 
|  | ; CHECK: bb20.preheader | 
|  | ; CHECK: **************************** | 
|  | ; CHECK: Loop Fusion complete | 
|  | define void @non_cfe(ptr noalias %arg, i32 %N) { | 
|  | bb: | 
|  | br label %bb7 | 
|  |  | 
|  | bb7:                                              ; preds = %bb, %bb14 | 
|  | %.014 = phi i32 [ 0, %bb ], [ %tmp15, %bb14 ] | 
|  | %indvars.iv23 = phi i64 [ 0, %bb ], [ %indvars.iv.next3, %bb14 ] | 
|  | %tmp = add nsw i32 %.014, -3 | 
|  | %tmp8 = add nuw nsw i64 %indvars.iv23, 3 | 
|  | %tmp9 = trunc i64 %tmp8 to i32 | 
|  | %tmp10 = mul nsw i32 %tmp, %tmp9 | 
|  | %tmp11 = trunc i64 %indvars.iv23 to i32 | 
|  | %tmp12 = srem i32 %tmp10, %tmp11 | 
|  | %tmp13 = getelementptr inbounds i32, ptr %arg, i64 %indvars.iv23 | 
|  | store i32 %tmp12, ptr %tmp13, align 4 | 
|  | br label %bb14 | 
|  |  | 
|  | bb14:                                             ; preds = %bb7 | 
|  | %indvars.iv.next3 = add nuw nsw i64 %indvars.iv23, 1 | 
|  | %tmp15 = add nuw nsw i32 %.014, 1 | 
|  | %exitcond4 = icmp ne i64 %indvars.iv.next3, 100 | 
|  | br i1 %exitcond4, label %bb7, label %bb34 | 
|  |  | 
|  | bb34: | 
|  | %cmp = icmp slt i32 %N, 50 | 
|  | br i1 %cmp, label %bb16, label %bb33 | 
|  |  | 
|  | bb16:                                             ; preds = %bb34 | 
|  | %tmp17 = load i32, ptr %arg, align 4 | 
|  | %tmp18 = icmp slt i32 %tmp17, 0 | 
|  | br i1 %tmp18, label %bb20.preheader, label %bb33 | 
|  |  | 
|  | bb20.preheader:                                   ; preds = %bb16 | 
|  | br label %bb22 | 
|  |  | 
|  | bb22:                                             ; preds = %bb20.preheader, %bb30 | 
|  | %.02 = phi i32 [ 0, %bb20.preheader ], [ %tmp31, %bb30 ] | 
|  | %indvars.iv1 = phi i64 [ 0, %bb20.preheader ], [ %indvars.iv.next, %bb30 ] | 
|  | %tmp23 = add nsw i32 %.02, -3 | 
|  | %tmp24 = add nuw nsw i64 %indvars.iv1, 3 | 
|  | %tmp25 = trunc i64 %tmp24 to i32 | 
|  | %tmp26 = mul nsw i32 %tmp23, %tmp25 | 
|  | %tmp27 = trunc i64 %indvars.iv1 to i32 | 
|  | %tmp28 = srem i32 %tmp26, %tmp27 | 
|  | %tmp29 = getelementptr inbounds [1024 x i32], ptr @B, i64 0, i64 %indvars.iv1 | 
|  | store i32 %tmp28, ptr %tmp29, align 4 | 
|  | br label %bb30 | 
|  |  | 
|  | bb30:                                             ; preds = %bb22 | 
|  | %indvars.iv.next = add nuw nsw i64 %indvars.iv1, 1 | 
|  | %tmp31 = add nuw nsw i32 %.02, 1 | 
|  | %exitcond = icmp ne i64 %indvars.iv.next, 100 | 
|  | br i1 %exitcond, label %bb22, label %bb33.loopexit | 
|  |  | 
|  | bb33.loopexit:                                    ; preds = %bb30 | 
|  | br label %bb33 | 
|  |  | 
|  | bb33:                                             ; preds = %bb33.loopexit, %bb16, %bb34 | 
|  | ret void | 
|  | } | 
|  |  | 
|  | ; Check that fusion detects the two canddates are not adjacent (the exit block | 
|  | ; of the first candidate is not the preheader of the second candidate). | 
|  |  | 
|  | ; CHECK: Performing Loop Fusion on function non_adjacent | 
|  | ; CHECK: Fusion Candidates: | 
|  | ; CHECK: *** Fusion Candidate Set *** | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: **************************** | 
|  | ; CHECK: Attempting fusion on Candidate Set: | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER]] | 
|  | ; CHECK: Fusion candidates are not adjacent. Not fusing. | 
|  | ; CHECK: Loop Fusion complete | 
|  | define void @non_adjacent(ptr noalias %arg) { | 
|  | bb: | 
|  | br label %bb5 | 
|  |  | 
|  | bb4:                                              ; preds = %bb11 | 
|  | br label %bb13 | 
|  |  | 
|  | bb5:                                              ; preds = %bb, %bb11 | 
|  | %.013 = phi i64 [ 0, %bb ], [ %tmp12, %bb11 ] | 
|  | %tmp = add nsw i64 %.013, -3 | 
|  | %tmp6 = add nuw nsw i64 %.013, 3 | 
|  | %tmp7 = mul nsw i64 %tmp, %tmp6 | 
|  | %tmp8 = srem i64 %tmp7, %.013 | 
|  | %tmp9 = trunc i64 %tmp8 to i32 | 
|  | %tmp10 = getelementptr inbounds i32, ptr %arg, i64 %.013 | 
|  | store i32 %tmp9, ptr %tmp10, align 4 | 
|  | br label %bb11 | 
|  |  | 
|  | bb11:                                             ; preds = %bb5 | 
|  | %tmp12 = add nuw nsw i64 %.013, 1 | 
|  | %exitcond2 = icmp ne i64 %tmp12, 100 | 
|  | br i1 %exitcond2, label %bb5, label %bb4 | 
|  |  | 
|  | bb13:                                             ; preds = %bb4 | 
|  | br label %bb16 | 
|  |  | 
|  | bb15:                                             ; preds = %bb23 | 
|  | br label %bb25 | 
|  |  | 
|  | bb16:                                             ; preds = %bb13, %bb23 | 
|  | %.02 = phi i64 [ 0, %bb13 ], [ %tmp24, %bb23 ] | 
|  | %tmp17 = add nsw i64 %.02, -3 | 
|  | %tmp18 = add nuw nsw i64 %.02, 3 | 
|  | %tmp19 = mul nsw i64 %tmp17, %tmp18 | 
|  | %tmp20 = srem i64 %tmp19, %.02 | 
|  | %tmp21 = trunc i64 %tmp20 to i32 | 
|  | %tmp22 = getelementptr inbounds [1024 x i32], ptr @B, i64 0, i64 %.02 | 
|  | store i32 %tmp21, ptr %tmp22, align 4 | 
|  | br label %bb23 | 
|  |  | 
|  | bb23:                                             ; preds = %bb16 | 
|  | %tmp24 = add nuw nsw i64 %.02, 1 | 
|  | %exitcond = icmp ne i64 %tmp24, 100 | 
|  | br i1 %exitcond, label %bb16, label %bb15 | 
|  |  | 
|  | bb25:                                             ; preds = %bb15 | 
|  | ret void | 
|  | } | 
|  |  | 
|  | ; Check that the different bounds are detected and prevent fusion. | 
|  |  | 
|  | ; CHECK: Performing Loop Fusion on function different_bounds | 
|  | ; CHECK: Fusion Candidates: | 
|  | ; CHECK: *** Fusion Candidate Set *** | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: **************************** | 
|  | ; CHECK: Attempting fusion on Candidate Set: | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER]] | 
|  | ; CHECK: Fusion candidates do not have identical trip counts. Not fusing. | 
|  | ; CHECK: Loop Fusion complete | 
|  | define void @different_bounds(ptr noalias %arg) { | 
|  | bb: | 
|  | br label %bb5 | 
|  |  | 
|  | bb4:                                              ; preds = %bb11 | 
|  | br label %bb13 | 
|  |  | 
|  | bb5:                                              ; preds = %bb, %bb11 | 
|  | %.013 = phi i64 [ 0, %bb ], [ %tmp12, %bb11 ] | 
|  | %tmp = add nsw i64 %.013, -3 | 
|  | %tmp6 = add nuw nsw i64 %.013, 3 | 
|  | %tmp7 = mul nsw i64 %tmp, %tmp6 | 
|  | %tmp8 = srem i64 %tmp7, %.013 | 
|  | %tmp9 = trunc i64 %tmp8 to i32 | 
|  | %tmp10 = getelementptr inbounds i32, ptr %arg, i64 %.013 | 
|  | store i32 %tmp9, ptr %tmp10, align 4 | 
|  | br label %bb11 | 
|  |  | 
|  | bb11:                                             ; preds = %bb5 | 
|  | %tmp12 = add nuw nsw i64 %.013, 1 | 
|  | %exitcond2 = icmp ne i64 %tmp12, 100 | 
|  | br i1 %exitcond2, label %bb5, label %bb4 | 
|  |  | 
|  | bb13:                                             ; preds = %bb4 | 
|  | br label %bb16 | 
|  |  | 
|  | bb15:                                             ; preds = %bb23 | 
|  | br label %bb25 | 
|  |  | 
|  | bb16:                                             ; preds = %bb13, %bb23 | 
|  | %.02 = phi i64 [ 0, %bb13 ], [ %tmp24, %bb23 ] | 
|  | %tmp17 = add nsw i64 %.02, -3 | 
|  | %tmp18 = add nuw nsw i64 %.02, 3 | 
|  | %tmp19 = mul nsw i64 %tmp17, %tmp18 | 
|  | %tmp20 = srem i64 %tmp19, %.02 | 
|  | %tmp21 = trunc i64 %tmp20 to i32 | 
|  | %tmp22 = getelementptr inbounds [1024 x i32], ptr @B, i64 0, i64 %.02 | 
|  | store i32 %tmp21, ptr %tmp22, align 4 | 
|  | br label %bb23 | 
|  |  | 
|  | bb23:                                             ; preds = %bb16 | 
|  | %tmp24 = add nuw nsw i64 %.02, 1 | 
|  | %exitcond = icmp ne i64 %tmp24, 200 | 
|  | br i1 %exitcond, label %bb16, label %bb15 | 
|  |  | 
|  | bb25:                                             ; preds = %bb15 | 
|  | ret void | 
|  | } | 
|  |  | 
|  | ; Check that the negative dependence between the two candidates is identified | 
|  | ; and prevents fusion. | 
|  |  | 
|  | ; CHECK: Performing Loop Fusion on function negative_dependence | 
|  | ; CHECK: Fusion Candidates: | 
|  | ; CHECK: *** Fusion Candidate Set *** | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: **************************** | 
|  | ; CHECK: Attempting fusion on Candidate Set: | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER]] | 
|  | ; CHECK: Memory dependencies do not allow fusion! | 
|  | ; CHECK: Loop Fusion complete | 
|  | define void @negative_dependence(ptr noalias %arg) { | 
|  | bb: | 
|  | br label %bb7 | 
|  |  | 
|  | bb11.preheader:                                   ; preds = %bb9 | 
|  | br label %bb13 | 
|  |  | 
|  | bb7:                                              ; preds = %bb, %bb9 | 
|  | %indvars.iv22 = phi i64 [ 0, %bb ], [ %indvars.iv.next3, %bb9 ] | 
|  | %tmp = getelementptr inbounds i32, ptr %arg, i64 %indvars.iv22 | 
|  | %tmp8 = trunc i64 %indvars.iv22 to i32 | 
|  | store i32 %tmp8, ptr %tmp, align 4 | 
|  | br label %bb9 | 
|  |  | 
|  | bb9:                                              ; preds = %bb7 | 
|  | %indvars.iv.next3 = add nuw nsw i64 %indvars.iv22, 1 | 
|  | %exitcond4 = icmp ne i64 %indvars.iv.next3, 100 | 
|  | br i1 %exitcond4, label %bb7, label %bb11.preheader | 
|  |  | 
|  | bb13:                                             ; preds = %bb11.preheader, %bb18 | 
|  | %indvars.iv1 = phi i64 [ 0, %bb11.preheader ], [ %indvars.iv.next, %bb18 ] | 
|  | %indvars.iv.next = add nuw nsw i64 %indvars.iv1, 1 | 
|  | %tmp14 = getelementptr inbounds i32, ptr %arg, i64 %indvars.iv.next | 
|  | %tmp15 = load i32, ptr %tmp14, align 4 | 
|  | %tmp16 = shl nsw i32 %tmp15, 1 | 
|  | %tmp17 = getelementptr inbounds [1024 x i32], ptr @B, i64 0, i64 %indvars.iv1 | 
|  | store i32 %tmp16, ptr %tmp17, align 4 | 
|  | br label %bb18 | 
|  |  | 
|  | bb18:                                             ; preds = %bb13 | 
|  | %exitcond = icmp ne i64 %indvars.iv.next, 100 | 
|  | br i1 %exitcond, label %bb13, label %bb19 | 
|  |  | 
|  | bb19:                                             ; preds = %bb18 | 
|  | ret void | 
|  | } | 
|  |  | 
|  | ; Check for values defined in Loop 0 and used in Loop 1. | 
|  | ; It is not safe to fuse in this case, because the second loop has | 
|  | ; a use of %.01.lcssa which is defined in the body of loop 0. The | 
|  | ; first loop must execute completely in order to compute the correct | 
|  | ; value of %.01.lcssa to be used in the second loop. | 
|  |  | 
|  | ; CHECK: Performing Loop Fusion on function sumTest | 
|  | ; CHECK: Fusion Candidates: | 
|  | ; CHECK: *** Fusion Candidate Set *** | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER:bb[0-9]*]] | 
|  | ; CHECK-NEXT: **************************** | 
|  | ; CHECK: Attempting fusion on Candidate Set: | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER]] | 
|  | ; CHECK: Memory dependencies do not allow fusion! | 
|  | ; CHECK: Loop Fusion complete | 
|  | define i32 @sumTest(ptr noalias %arg) { | 
|  | bb: | 
|  | br label %bb9 | 
|  |  | 
|  | bb13.preheader:                                   ; preds = %bb9 | 
|  | br label %bb15 | 
|  |  | 
|  | bb9:                                              ; preds = %bb, %bb9 | 
|  | %.01.lcssa = phi i32 [ 0, %bb ], [ %tmp11, %bb9 ] | 
|  | %.013 = phi i32 [ 0, %bb ], [ %tmp11, %bb9 ] | 
|  | %indvars.iv32 = phi i64 [ 0, %bb ], [ %indvars.iv.next4, %bb9 ] | 
|  | %tmp = getelementptr inbounds i32, ptr %arg, i64 %indvars.iv32 | 
|  | %tmp10 = load i32, ptr %tmp, align 4 | 
|  | %tmp11 = add nsw i32 %.013, %tmp10 | 
|  | %indvars.iv.next4 = add nuw nsw i64 %indvars.iv32, 1 | 
|  | %exitcond5 = icmp ne i64 %indvars.iv.next4, 100 | 
|  | br i1 %exitcond5, label %bb9, label %bb13.preheader | 
|  |  | 
|  | bb14:                                             ; preds = %bb20 | 
|  | br label %bb21 | 
|  |  | 
|  | bb15:                                             ; preds = %bb13.preheader, %bb20 | 
|  | %indvars.iv1 = phi i64 [ 0, %bb13.preheader ], [ %indvars.iv.next, %bb20 ] | 
|  | %tmp16 = getelementptr inbounds i32, ptr %arg, i64 %indvars.iv1 | 
|  | %tmp17 = load i32, ptr %tmp16, align 4 | 
|  | %tmp18 = sdiv i32 %tmp17, %.01.lcssa | 
|  | %tmp19 = getelementptr inbounds [1024 x i32], ptr @B, i64 0, i64 %indvars.iv1 | 
|  | store i32 %tmp18, ptr %tmp19, align 4 | 
|  | br label %bb20 | 
|  |  | 
|  | bb20:                                             ; preds = %bb15 | 
|  | %indvars.iv.next = add nuw nsw i64 %indvars.iv1, 1 | 
|  | %exitcond = icmp ne i64 %indvars.iv.next, 100 | 
|  | br i1 %exitcond, label %bb15, label %bb14 | 
|  |  | 
|  | bb21:                                             ; preds = %bb14 | 
|  | ret i32 %.01.lcssa | 
|  | } | 
|  |  | 
|  | ; Similar to sumTest above. The first loop computes %add and must | 
|  | ; complete before it is used in the second loop. Thus, these two loops | 
|  | ; also cannot be fused. | 
|  |  | 
|  | ; CHECK: Performing Loop Fusion on function test | 
|  | ; CHECK: Fusion Candidates: | 
|  | ; CHECK: *** Fusion Candidate Set *** | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER:for.body[0-9]*.preheader]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER:for.body[0-9]*.preheader]] | 
|  | ; CHECK-NEXT: **************************** | 
|  | ; CHECK: Attempting fusion on Candidate Set: | 
|  | ; CHECK-NEXT: [[LOOP1PREHEADER]] | 
|  | ; CHECK-NEXT: [[LOOP2PREHEADER]] | 
|  | ; CHECK: Memory dependencies do not allow fusion! | 
|  | ; CHECK: Loop Fusion complete | 
|  | define float @test(ptr nocapture %a, i32 %n) { | 
|  | entry: | 
|  | %conv = zext i32 %n to i64 | 
|  | %cmp32 = icmp eq i32 %n, 0 | 
|  | br i1 %cmp32, label %for.cond.cleanup7, label %for.body | 
|  |  | 
|  | for.body:                                         ; preds = %for.body, %entry | 
|  | %i.034 = phi i64 [ %inc, %for.body ], [ 0, %entry ] | 
|  | %sum1.033 = phi float [ %add, %for.body ], [ 0.000000e+00, %entry ] | 
|  | %idxprom = trunc i64 %i.034 to i32 | 
|  | %arrayidx = getelementptr inbounds float, ptr %a, i32 %idxprom | 
|  | %0 = load float, ptr %arrayidx, align 4 | 
|  | %add = fadd float %sum1.033, %0 | 
|  | %inc = add nuw nsw i64 %i.034, 1 | 
|  | %cmp = icmp ult i64 %inc, %conv | 
|  | br i1 %cmp, label %for.body, label %for.body8 | 
|  |  | 
|  | for.body8:                                        ; preds = %for.body, %for.body8 | 
|  | %i2.031 = phi i64 [ %inc14, %for.body8 ], [ 0, %for.body ] | 
|  | %idxprom9 = trunc i64 %i2.031 to i32 | 
|  | %arrayidx10 = getelementptr inbounds float, ptr %a, i32 %idxprom9 | 
|  | %1 = load float, ptr %arrayidx10, align 4 | 
|  | %div = fdiv float %1, %add | 
|  | store float %div, ptr %arrayidx10, align 4 | 
|  | %inc14 = add nuw nsw i64 %i2.031, 1 | 
|  | %cmp5 = icmp ult i64 %inc14, %conv | 
|  | br i1 %cmp5, label %for.body8, label %for.cond.cleanup7 | 
|  |  | 
|  | for.cond.cleanup7:                                ; preds = %for.body8, %entry | 
|  | %sum1.0.lcssa36 = phi float [ 0.000000e+00, %entry ], [ %add, %for.body8 ] | 
|  | ret float %sum1.0.lcssa36 | 
|  | } | 
|  |  | 
|  | ; Check that non-rotated loops are not considered for fusion. | 
|  | ; CHECK: Performing Loop Fusion on function notRotated | 
|  | ; CHECK: Loop bb{{.*}} is not rotated! | 
|  | ; CHECK: Loop bb{{.*}} is not rotated! | 
|  | define void @notRotated(ptr noalias %arg) { | 
|  | bb: | 
|  | br label %bb5 | 
|  |  | 
|  | bb5:                                              ; preds = %bb14, %bb | 
|  | %indvars.iv2 = phi i64 [ %indvars.iv.next3, %bb14 ], [ 0, %bb ] | 
|  | %.01 = phi i32 [ 0, %bb ], [ %tmp15, %bb14 ] | 
|  | %exitcond4 = icmp ne i64 %indvars.iv2, 100 | 
|  | br i1 %exitcond4, label %bb7, label %bb17 | 
|  |  | 
|  | bb7:                                              ; preds = %bb5 | 
|  | %tmp = add nsw i32 %.01, -3 | 
|  | %tmp8 = add nuw nsw i64 %indvars.iv2, 3 | 
|  | %tmp9 = trunc i64 %tmp8 to i32 | 
|  | %tmp10 = mul nsw i32 %tmp, %tmp9 | 
|  | %tmp11 = trunc i64 %indvars.iv2 to i32 | 
|  | %tmp12 = srem i32 %tmp10, %tmp11 | 
|  | %tmp13 = getelementptr inbounds i32, ptr %arg, i64 %indvars.iv2 | 
|  | store i32 %tmp12, ptr %tmp13, align 4 | 
|  | br label %bb14 | 
|  |  | 
|  | bb14:                                             ; preds = %bb7 | 
|  | %indvars.iv.next3 = add nuw nsw i64 %indvars.iv2, 1 | 
|  | %tmp15 = add nuw nsw i32 %.01, 1 | 
|  | br label %bb5 | 
|  |  | 
|  | bb17:                                             ; preds = %bb27, %bb5 | 
|  | %indvars.iv = phi i64 [ %indvars.iv.next, %bb27 ], [ 0, %bb5 ] | 
|  | %.0 = phi i32 [ 0, %bb5 ], [ %tmp28, %bb27 ] | 
|  | %exitcond = icmp ne i64 %indvars.iv, 100 | 
|  | br i1 %exitcond, label %bb19, label %bb18 | 
|  |  | 
|  | bb18:                                             ; preds = %bb17 | 
|  | br label %bb29 | 
|  |  | 
|  | bb19:                                             ; preds = %bb17 | 
|  | %tmp20 = add nsw i32 %.0, -3 | 
|  | %tmp21 = add nuw nsw i64 %indvars.iv, 3 | 
|  | %tmp22 = trunc i64 %tmp21 to i32 | 
|  | %tmp23 = mul nsw i32 %tmp20, %tmp22 | 
|  | %tmp24 = trunc i64 %indvars.iv to i32 | 
|  | %tmp25 = srem i32 %tmp23, %tmp24 | 
|  | %tmp26 = getelementptr inbounds [1024 x i32], ptr @B, i64 0, i64 %indvars.iv | 
|  | store i32 %tmp25, ptr %tmp26, align 4 | 
|  | br label %bb27 | 
|  |  | 
|  | bb27:                                             ; preds = %bb19 | 
|  | %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 | 
|  | %tmp28 = add nuw nsw i32 %.0, 1 | 
|  | br label %bb17 | 
|  |  | 
|  | bb29:                                             ; preds = %bb18 | 
|  | ret void | 
|  | } |