xref: /aosp_15_r20/external/llvm/test/Analysis/ScalarEvolution/nw-sub-is-not-nw-add.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1*9880d681SAndroid Build Coastguard Worker; RUN: opt -S -indvars < %s | FileCheck %s
2*9880d681SAndroid Build Coastguard Worker
3*9880d681SAndroid Build Coastguard Worker; Check that SCEV does not assume sub nuw X Y == add nuw X, -Y
4*9880d681SAndroid Build Coastguard Workerdefine void @f(i32* %loc) {
5*9880d681SAndroid Build Coastguard Worker; CHECK-LABEL: @f
6*9880d681SAndroid Build Coastguard Worker entry:
7*9880d681SAndroid Build Coastguard Worker  br label %loop
8*9880d681SAndroid Build Coastguard Worker
9*9880d681SAndroid Build Coastguard Worker loop:
10*9880d681SAndroid Build Coastguard Worker  %idx = phi i32 [ 6, %entry ], [ %idx.dec, %loop ]
11*9880d681SAndroid Build Coastguard Worker  store i32 %idx, i32* %loc
12*9880d681SAndroid Build Coastguard Worker  %idx.dec = sub nuw i32 %idx, 1
13*9880d681SAndroid Build Coastguard Worker  %cond = icmp uge i32 %idx.dec, 5
14*9880d681SAndroid Build Coastguard Worker  br i1 %cond, label %loop, label %exit
15*9880d681SAndroid Build Coastguard Worker; CHECK-NOT: br i1 true, label %loop, label %exit
16*9880d681SAndroid Build Coastguard Worker
17*9880d681SAndroid Build Coastguard Worker exit:
18*9880d681SAndroid Build Coastguard Worker  ret void
19*9880d681SAndroid Build Coastguard Worker}
20*9880d681SAndroid Build Coastguard Worker
21*9880d681SAndroid Build Coastguard Workerdeclare void @use_i1(i1)
22*9880d681SAndroid Build Coastguard Worker
23*9880d681SAndroid Build Coastguard Worker; Check that SCEV does not assume sub nsw X Y == add nsw X, -Y
24*9880d681SAndroid Build Coastguard Workerdefine void @g(i32 %lim) {
25*9880d681SAndroid Build Coastguard Worker; CHECK-LABEL: @g
26*9880d681SAndroid Build Coastguard Worker entry:
27*9880d681SAndroid Build Coastguard Worker  br label %loop
28*9880d681SAndroid Build Coastguard Worker
29*9880d681SAndroid Build Coastguard Worker loop:
30*9880d681SAndroid Build Coastguard Worker  %idx = phi i32 [ -1, %entry ], [ %idx.dec, %loop ]
31*9880d681SAndroid Build Coastguard Worker  %t = icmp sgt i32 %idx, 0
32*9880d681SAndroid Build Coastguard Worker; CHECK-NOT:   call void @use_i1(i1 false)
33*9880d681SAndroid Build Coastguard Worker; CHECK: call void @use_i1(i1 %t)
34*9880d681SAndroid Build Coastguard Worker  call void @use_i1(i1 %t)
35*9880d681SAndroid Build Coastguard Worker  %idx.dec = sub nsw i32 %idx, -2147483648
36*9880d681SAndroid Build Coastguard Worker  %cond = icmp eq i32 %idx.dec, %lim
37*9880d681SAndroid Build Coastguard Worker  br i1 %cond, label %loop, label %exit
38*9880d681SAndroid Build Coastguard Worker
39*9880d681SAndroid Build Coastguard Worker exit:
40*9880d681SAndroid Build Coastguard Worker  ret void
41*9880d681SAndroid Build Coastguard Worker}
42