1 ; RUN: opt -S -indvars < %s | FileCheck %s 2 3 ; Check that SCEV does not assume sub nuw X Y == add nuw X, -Y 4 define void @f(i32* %loc) { 5 ; CHECK-LABEL: @f 6 entry: 7 br label %loop 8 9 loop: 10 %idx = phi i32 [ 6, %entry ], [ %idx.dec, %loop ] 11 store i32 %idx, i32* %loc 12 %idx.dec = sub nuw i32 %idx, 1 13 %cond = icmp uge i32 %idx.dec, 5 14 br i1 %cond, label %loop, label %exit 15 ; CHECK-NOT: br i1 true, label %loop, label %exit 16 17 exit: 18 ret void 19 } 20 21 declare void @use_i1(i1) 22 23 ; Check that SCEV does not assume sub nsw X Y == add nsw X, -Y 24 define void @g(i32 %lim) { 25 ; CHECK-LABEL: @g 26 entry: 27 br label %loop 28 29 loop: 30 %idx = phi i32 [ -1, %entry ], [ %idx.dec, %loop ] 31 %t = icmp sgt i32 %idx, 0 32 ; CHECK-NOT: call void @use_i1(i1 false) 33 ; CHECK: call void @use_i1(i1 %t) 34 call void @use_i1(i1 %t) 35 %idx.dec = sub nsw i32 %idx, -2147483648 36 %cond = icmp eq i32 %idx.dec, %lim 37 br i1 %cond, label %loop, label %exit 38 39 exit: 40 ret void 41 } 42
