1 ; RUN: opt < %s -loop-unswitch -verify-loop-info -S < %s 2>&1 | FileCheck %s 2 3 ; There are 1 case and 1 default case in the switch. after we unswitch, we know the 4 ; %a is definitely not 0 in one of the unswitched loop, make sure we take advantage 5 ; of that and simplify the branches in the loop. 6 ; 7 ; CHECK: define void @simplify_with_nonvalness( 8 9 ; This is the loop in which we know %a is definitely 0. 10 ; CHECK: sw.bb.us: 11 ; CHECK: br i1 true, label %if.then.us, label %if.end.us 12 13 ; This is the loop in which we do not know what %a is but we know %a is definitely NOT 0. 14 ; Make sure we use that information to simplify. 15 ; The icmp eq i32 %a, 0 in one of the unswitched loop is simplified to false. 16 ; CHECK: sw.bb.split: 17 ; CHECK: br i1 false, label %if.then, label %if.end 18 19 define void @simplify_with_nonvalness(i32 %a) #0 { 20 entry: 21 br label %for.cond 22 23 for.cond: 24 %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ] 25 %cmp = icmp slt i32 %i.0, 1024 26 br i1 %cmp, label %for.body, label %for.end 27 28 for.body: 29 switch i32 %a, label %sw.default [ 30 i32 0, label %sw.bb 31 ] 32 33 sw.bb: 34 %cmp1 = icmp eq i32 %a, 0 35 br i1 %cmp1, label %if.then, label %if.end 36 37 if.then: 38 call void (...) @bar() 39 br label %if.end 40 41 if.end: 42 br label %sw.epilog 43 44 sw.default: 45 br label %sw.epilog 46 47 sw.epilog: 48 br label %for.inc 49 50 for.inc: 51 %inc = add nsw i32 %i.0, 1 52 br label %for.cond 53 54 for.end: 55 ret void 56 } 57 58 declare void @bar(...) 59
