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; RUN: llc -mtriple=aarch64-none-linux-gnu -verify-machineinstrs < %s | FileCheck %s
define i32 @foo(i32* %var, i1 %cond) {
; CHECK-LABEL: foo:
br i1 %cond, label %atomic_ver, label %simple_ver
simple_ver:
%oldval = load i32* %var
%newval = add nsw i32 %oldval, -1
store i32 %newval, i32* %var
br label %somewhere
atomic_ver:
fence seq_cst
%val = atomicrmw add i32* %var, i32 -1 monotonic
fence seq_cst
br label %somewhere
; CHECK: dmb
; CHECK: ldxr
; CHECK: dmb
; The key point here is that the second dmb isn't immediately followed by the
; simple_ver basic block, which LLVM attempted to do when DMB had been marked
; with isBarrier. For now, look for something that looks like "somewhere".
; CHECK-NEXT: mov
somewhere:
%combined = phi i32 [ %val, %atomic_ver ], [ %newval, %simple_ver]
ret i32 %combined
}
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