cmpxchg-idioms.ll
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; RUN: llc -mtriple=thumbv7s-apple-ios7.0 -o - %s | FileCheck %s
define i32 @test_return(i32* %p, i32 %oldval, i32 %newval) {
; CHECK-LABEL: test_return:
; CHECK: ldrex [[LOADED:r[0-9]+]], [r0]
; CHECK: cmp [[LOADED]], r1
; CHECK: bne [[FAILED:LBB[0-9]+_[0-9]+]]
; CHECK: dmb ishst
; CHECK: [[LOOP:LBB[0-9]+_[0-9]+]]:
; CHECK: strex [[STATUS:r[0-9]+]], {{r[0-9]+}}, [r0]
; CHECK: cbz [[STATUS]], [[SUCCESS:LBB[0-9]+_[0-9]+]]
; CHECK: ldrex [[LOADED]], [r0]
; CHECK: cmp [[LOADED]], r1
; CHECK: beq [[LOOP]]
; CHECK: [[FAILED]]:
; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
; CHECK: clrex
; CHECK: movs r0, #0
; CHECK: dmb ish
; CHECK: bx lr
; CHECK: [[SUCCESS]]:
; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
; CHECK: movs r0, #1
; CHECK: dmb ish
; CHECK: bx lr
%pair = cmpxchg i32* %p, i32 %oldval, i32 %newval seq_cst seq_cst
%success = extractvalue { i32, i1 } %pair, 1
%conv = zext i1 %success to i32
ret i32 %conv
}
define i1 @test_return_bool(i8* %value, i8 %oldValue, i8 %newValue) {
; CHECK-LABEL: test_return_bool:
; CHECK: uxtb [[OLDBYTE:r[0-9]+]], r1
; CHECK: ldrexb [[LOADED:r[0-9]+]], [r0]
; CHECK: cmp [[LOADED]], [[OLDBYTE]]
; CHECK: bne [[FAIL:LBB[0-9]+_[0-9]+]]
; CHECK: dmb ishst
; CHECK: [[LOOP:LBB[0-9]+_[0-9]+]]:
; CHECK: strexb [[STATUS:r[0-9]+]], {{r[0-9]+}}, [r0]
; CHECK: cbz [[STATUS]], [[SUCCESS:LBB[0-9]+_[0-9]+]]
; CHECK: ldrexb [[LOADED]], [r0]
; CHECK: cmp [[LOADED]], [[OLDBYTE]]
; CHECK: beq [[LOOP]]
; FIXME: this eor is redundant. Need to teach DAG combine that.
; CHECK: [[FAIL]]:
; CHECK: clrex
; CHECK: movs [[TMP:r[0-9]+]], #0
; CHECK: eor r0, [[TMP]], #1
; CHECK: bx lr
; CHECK: [[SUCCESS]]:
; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
; CHECK: movs [[TMP:r[0-9]+]], #1
; CHECK: eor r0, [[TMP]], #1
; CHECK: bx lr
%pair = cmpxchg i8* %value, i8 %oldValue, i8 %newValue acq_rel monotonic
%success = extractvalue { i8, i1 } %pair, 1
%failure = xor i1 %success, 1
ret i1 %failure
}
define void @test_conditional(i32* %p, i32 %oldval, i32 %newval) {
; CHECK-LABEL: test_conditional:
; CHECK: ldrex [[LOADED:r[0-9]+]], [r0]
; CHECK: cmp [[LOADED]], r1
; CHECK: bne [[FAILED:LBB[0-9]+_[0-9]+]]
; CHECK: dmb ishst
; CHECK: [[LOOP:LBB[0-9]+_[0-9]+]]:
; CHECK: strex [[STATUS:r[0-9]+]], r2, [r0]
; CHECK: cbz [[STATUS]], [[SUCCESS:LBB[0-9]+_[0-9]+]]
; CHECK: ldrex [[LOADED]], [r0]
; CHECK: cmp [[LOADED]], r1
; CHECK: beq [[LOOP]]
; CHECK: [[FAILED]]:
; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
; CHECK: clrex
; CHECK: dmb ish
; CHECK: b.w _baz
; CHECK: [[SUCCESS]]:
; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
; CHECK: dmb ish
; CHECK: b.w _bar
%pair = cmpxchg i32* %p, i32 %oldval, i32 %newval seq_cst seq_cst
%success = extractvalue { i32, i1 } %pair, 1
br i1 %success, label %true, label %false
true:
tail call void @bar() #2
br label %end
false:
tail call void @baz() #2
br label %end
end:
ret void
}
declare void @bar()
declare void @baz()