1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2 3; We run -passes=indvars before -passes=simple-loop-unswitch to compute SCEV exit counts before 4; running -simple-loop-unswitch. 5; RUN: opt -passes=indvars,simple-loop-unswitch -S %s -verify-scev | FileCheck %s 6 7; Test for PR43972. 8 9; We have a 3 nested loops (l1 <- l2 <- l3). %for.cond.5 is the exit block of 10; l3 and the loop for it is l2. But it is also the exiting block of l1. That 11; means we have to invalidate l1 to preserve SCEV. 12 13define void @f() { 14; CHECK-LABEL: @f( 15; CHECK-NEXT: entry: 16; CHECK-NEXT: [[LNOT:%.*]] = xor i1 undef, true 17; CHECK-NEXT: br label [[FOR_COND:%.*]] 18; CHECK: for.cond.loopexit: 19; CHECK-NEXT: br label [[FOR_COND]] 20; CHECK: for.cond: 21; CHECK-NEXT: br label [[FOR_BODY:%.*]] 22; CHECK: for.cond1: 23; CHECK-NEXT: br i1 true, label [[FOR_BODY]], label [[FOR_COND_LOOPEXIT:%.*]] 24; CHECK: for.body: 25; CHECK-NEXT: br i1 [[LNOT]], label [[FOR_BODY_SPLIT:%.*]], label [[FOR_COND5_SPLIT:%.*]] 26; CHECK: for.body.split: 27; CHECK-NEXT: br label [[LAND_RHS:%.*]] 28; CHECK: for.cond2: 29; CHECK-NEXT: br i1 true, label [[LAND_RHS]], label [[FOR_COND5:%.*]] 30; CHECK: land.rhs: 31; CHECK-NEXT: br label [[FOR_COND2:%.*]] 32; CHECK: for.cond5: 33; CHECK-NEXT: br label [[FOR_COND5_SPLIT]] 34; CHECK: for.cond5.split: 35; CHECK-NEXT: br i1 true, label [[FOR_BODY7:%.*]], label [[FOR_COND1:%.*]] 36; CHECK: for.body7: 37; CHECK-NEXT: ret void 38; 39entry: 40 %lnot = xor i1 undef, true 41 br label %for.cond 42 43for.cond: ; preds = %for.cond1, %entry 44 br label %for.body 45 46for.cond1: ; preds = %for.cond5 47 br i1 true, label %for.body, label %for.cond 48 49for.body: ; preds = %for.cond1, %for.cond 50 br label %land.rhs 51 52for.cond2: ; preds = %land.rhs 53 br i1 true, label %land.rhs, label %for.cond5 54 55land.rhs: ; preds = %for.cond2, %for.body 56 br i1 %lnot, label %for.cond2, label %for.cond5 57 58for.cond5: ; preds = %land.rhs, %for.cond2 59 br i1 true, label %for.body7, label %for.cond1 60 61for.body7: ; preds = %for.cond5 62 ret void 63} 64