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; RUN: opt -S -indvars < %s | FileCheck %s
; Check that SCEV does not assume sub nuw X Y == add nuw X, -Y
define void @f(i32* %loc) {
; CHECK-LABEL: @f
entry:
br label %loop
loop:
%idx = phi i32 [ 6, %entry ], [ %idx.dec, %loop ]
store i32 %idx, i32* %loc
%idx.dec = sub nuw i32 %idx, 1
%cond = icmp uge i32 %idx.dec, 5
br i1 %cond, label %loop, label %exit
; CHECK-NOT: br i1 true, label %loop, label %exit
exit:
ret void
}
declare void @use_i1(i1)
; Check that SCEV does not assume sub nsw X Y == add nsw X, -Y
define void @g(i32 %lim) {
; CHECK-LABEL: @g
entry:
br label %loop
loop:
%idx = phi i32 [ -1, %entry ], [ %idx.dec, %loop ]
%t = icmp sgt i32 %idx, 0
; CHECK-NOT: call void @use_i1(i1 false)
; CHECK: call void @use_i1(i1 %t)
call void @use_i1(i1 %t)
%idx.dec = sub nsw i32 %idx, -2147483648
%cond = icmp eq i32 %idx.dec, %lim
br i1 %cond, label %loop, label %exit
exit:
ret void
}
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