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; RUN: llc < %s -mtriple=aarch64 -O=3 | FileCheck %s
define void @test() {
; CHECK: dmb sy
call void @llvm.aarch64.dmb(i32 15)
; CHECK: dmb osh
call void @llvm.aarch64.dmb(i32 3)
; CHECK: dsb sy
call void @llvm.aarch64.dsb(i32 15)
; CHECK: dsb ishld
call void @llvm.aarch64.dsb(i32 9)
; CHECK: isb
call void @llvm.aarch64.isb(i32 15)
ret void
}
; Important point is that the compiler should not reorder memory access
; instructions around DMB.
; Failure to do so, two STRs will collapse into one STP.
define void @test_dmb_reordering(i32 %a, i32 %b, ptr %d) {
store i32 %a, ptr %d ; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}]
call void @llvm.aarch64.dmb(i32 15); CHECK: dmb sy
%d1 = getelementptr i32, ptr %d, i64 1
store i32 %b, ptr %d1 ; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}, #4]
ret void
}
; Similarly for DSB.
define void @test_dsb_reordering(i32 %a, i32 %b, ptr %d) {
store i32 %a, ptr %d ; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}]
call void @llvm.aarch64.dsb(i32 15); CHECK: dsb sy
%d1 = getelementptr i32, ptr %d, i64 1
store i32 %b, ptr %d1 ; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}, #4]
ret void
}
; And ISB.
define void @test_isb_reordering(i32 %a, i32 %b, ptr %d) {
store i32 %a, ptr %d ; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}]
call void @llvm.aarch64.isb(i32 15); CHECK: isb
%d1 = getelementptr i32, ptr %d, i64 1
store i32 %b, ptr %d1 ; CHECK: str {{w[0-9]+}}, [{{x[0-9]+}}, #4]
ret void
}
declare void @llvm.aarch64.dmb(i32)
declare void @llvm.aarch64.dsb(i32)
declare void @llvm.aarch64.isb(i32)
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