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; RUN: llc < %s -mtriple=armv7 -mattr=+db | FileCheck %s
; RUN: llc < %s -mtriple=thumbv7 -mattr=+db | FileCheck %s
; CHECK-LABEL: test
define void @test() {
call void @llvm.arm.dmb(i32 3) ; CHECK: dmb osh
call void @llvm.arm.dsb(i32 7) ; CHECK: dsb nsh
call void @llvm.arm.isb(i32 15) ; CHECK: isb sy
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 STRD.
; CHECK-LABEL: test_dmb_reordering
define void @test_dmb_reordering(i32 %a, i32 %b, i32* %d) {
store i32 %a, i32* %d ; CHECK: str {{r[0-9]+}}, [{{r[0-9]+}}]
call void @llvm.arm.dmb(i32 15) ; CHECK: dmb sy
%d1 = getelementptr i32* %d, i32 1
store i32 %b, i32* %d1 ; CHECK: str {{r[0-9]+}}, [{{r[0-9]+}}, #4]
ret void
}
; Similarly for DSB.
; CHECK-LABEL: test_dsb_reordering
define void @test_dsb_reordering(i32 %a, i32 %b, i32* %d) {
store i32 %a, i32* %d ; CHECK: str {{r[0-9]+}}, [{{r[0-9]+}}]
call void @llvm.arm.dsb(i32 15) ; CHECK: dsb sy
%d1 = getelementptr i32* %d, i32 1
store i32 %b, i32* %d1 ; CHECK: str {{r[0-9]+}}, [{{r[0-9]+}}, #4]
ret void
}
; And ISB.
; CHECK-LABEL: test_isb_reordering
define void @test_isb_reordering(i32 %a, i32 %b, i32* %d) {
store i32 %a, i32* %d ; CHECK: str {{r[0-9]+}}, [{{r[0-9]+}}]
call void @llvm.arm.isb(i32 15) ; CHECK: isb sy
%d1 = getelementptr i32* %d, i32 1
store i32 %b, i32* %d1 ; CHECK: str {{r[0-9]+}}, [{{r[0-9]+}}, #4]
ret void
}
declare void @llvm.arm.dmb(i32)
declare void @llvm.arm.dsb(i32)
declare void @llvm.arm.isb(i32)
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