1 files changed, 107 insertions, 0 deletions
diff --git a/test/CodeGen/ARM/cmpxchg-idioms.ll b/test/CodeGen/ARM/cmpxchg-idioms.ll
new file mode 100644
index 0000000..fb88575
--- /dev/null
+++ b/test/CodeGen/ARM/cmpxchg-idioms.ll
@@ -0,0 +1,107 @@
+; 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: dmb ishst
+
+; CHECK: [[LOOP:LBB[0-9]+_[0-9]+]]:
+; CHECK: ldrex [[LOADED:r[0-9]+]], [r0]
+; CHECK: cmp [[LOADED]], r1
+; CHECK: bne [[FAILED:LBB[0-9]+_[0-9]+]]
+
+; CHECK: strex [[STATUS:r[0-9]+]], {{r[0-9]+}}, [r0]
+; CHECK: cmp [[STATUS]], #0
+; CHECK: bne [[LOOP]]
+
+; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
+; CHECK: movs r0, #1
+; CHECK: dmb ish
+; CHECK: bx lr
+
+; CHECK: [[FAILED]]:
+; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
+; CHECK: movs r0, #0
+; 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: dmb ishst
+
+; CHECK: [[LOOP:LBB[0-9]+_[0-9]+]]:
+; CHECK: ldrexb [[LOADED:r[0-9]+]], [r0]
+; CHECK: cmp [[LOADED]], [[OLDBYTE]]
+; CHECK: bne [[FAIL:LBB[0-9]+_[0-9]+]]
+
+; CHECK: strexb [[STATUS:r[0-9]+]], {{r[0-9]+}}, [r0]
+; CHECK: cmp [[STATUS]], #0
+; CHECK: bne [[LOOP]]
+
+  ; FIXME: this eor is redundant. Need to teach DAG combine that.
+; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
+; CHECK: movs [[TMP:r[0-9]+]], #1
+; CHECK: eor r0, [[TMP]], #1
+; CHECK: bx lr
+
+; CHECK: [[FAIL]]:
+; CHECK: movs [[TMP:r[0-9]+]], #0
+; 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: dmb ishst
+
+; CHECK: [[LOOP:LBB[0-9]+_[0-9]+]]:
+; CHECK: ldrex [[LOADED:r[0-9]+]], [r0]
+; CHECK: cmp [[LOADED]], r1
+; CHECK: bne [[FAILED:LBB[0-9]+_[0-9]+]]
+
+; CHECK: strex [[STATUS:r[0-9]+]], r2, [r0]
+; CHECK: cmp [[STATUS]], #0
+; CHECK: bne [[LOOP]]
+
+; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
+; CHECK: dmb ish
+; CHECK: b.w _bar
+
+; CHECK: [[FAILED]]:
+; CHECK-NOT: cmp {{r[0-9]+}}, {{r[0-9]+}}
+; CHECK: dmb ish
+; CHECK: b.w _baz
+
+  %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()