xref: /aosp_15_r20/external/llvm/test/CodeGen/AArch64/atomic-ops-not-barriers.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1*9880d681SAndroid Build Coastguard Worker; RUN: llc -mtriple=aarch64-none-linux-gnu -verify-machineinstrs < %s | FileCheck %s
2*9880d681SAndroid Build Coastguard Worker
3*9880d681SAndroid Build Coastguard Workerdefine i32 @foo(i32* %var, i1 %cond) {
4*9880d681SAndroid Build Coastguard Worker; CHECK-LABEL: foo:
5*9880d681SAndroid Build Coastguard Worker  br i1 %cond, label %atomic_ver, label %simple_ver
6*9880d681SAndroid Build Coastguard Workersimple_ver:
7*9880d681SAndroid Build Coastguard Worker  %oldval = load i32, i32* %var
8*9880d681SAndroid Build Coastguard Worker  %newval = add nsw i32 %oldval, -1
9*9880d681SAndroid Build Coastguard Worker  store i32 %newval, i32* %var
10*9880d681SAndroid Build Coastguard Worker  br label %somewhere
11*9880d681SAndroid Build Coastguard Workeratomic_ver:
12*9880d681SAndroid Build Coastguard Worker  fence seq_cst
13*9880d681SAndroid Build Coastguard Worker  %val = atomicrmw add i32* %var, i32 -1 monotonic
14*9880d681SAndroid Build Coastguard Worker  fence seq_cst
15*9880d681SAndroid Build Coastguard Worker  br label %somewhere
16*9880d681SAndroid Build Coastguard Worker; CHECK: dmb
17*9880d681SAndroid Build Coastguard Worker; CHECK: ldxr
18*9880d681SAndroid Build Coastguard Worker; CHECK: dmb
19*9880d681SAndroid Build Coastguard Worker  ; The key point here is that the second dmb isn't immediately followed by the
20*9880d681SAndroid Build Coastguard Worker  ; simple_ver basic block, which LLVM attempted to do when DMB had been marked
21*9880d681SAndroid Build Coastguard Worker  ; with isBarrier. For now, look for something that looks like "somewhere".
22*9880d681SAndroid Build Coastguard Worker; CHECK-NEXT: mov
23*9880d681SAndroid Build Coastguard Workersomewhere:
24*9880d681SAndroid Build Coastguard Worker  %combined = phi i32 [ %val, %atomic_ver ], [ %newval, %simple_ver]
25*9880d681SAndroid Build Coastguard Worker  ret i32 %combined
26*9880d681SAndroid Build Coastguard Worker}
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