Imported Upstream version 6.0.0.172

Former-commit-id: f3cc9b82f3e5bd8f0fd3ebc098f789556b44e9cd

external/llvm/test/CodeGen/ARM/intrinsics-memory-barrier.ll

@@ -0,0 +1,55 @@
+; 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, 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, 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, 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)