Add a test for r242281 from an old patch of mine.

This isn't thorough, but should serve as a sanity check.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242356 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Analysis/GlobalsModRef/atomic-instrs.ll b/test/Analysis/GlobalsModRef/atomic-instrs.ll
new file mode 100644 (file)
index 0000000..9e163ec
--- /dev/null
+++ b/test/Analysis/GlobalsModRef/atomic-instrs.ll
@@ -0,0 +1,37 @@
+; RUN: opt < %s -globalsmodref-aa -gvn -S | FileCheck %s
+
+@X = internal global i32 4
+
+define i32 @test_cmpxchg(i32* %P) {
+; CHECK-LABEL: @test_cmpxchg
+; CHECK-NEXT: store i32 12, i32* @X
+; CHECK-NEXT: call void @modrefX_cmpxchg()
+; CHECK-NEXT: %V = load i32, i32* @X
+; CHECK-NEXT: ret i32 %V
+  store i32 12, i32* @X
+  call void @modrefX_cmpxchg()
+  %V = load i32, i32* @X
+  ret i32 %V
+}
+
+define void @modrefX_cmpxchg() {
+  %1 = cmpxchg i32* @X, i32 0, i32 -1 monotonic monotonic
+  ret void
+}
+
+define i32 @test_atomicrmw(i32* %P) {
+; CHECK-LABEL: @test_atomicrmw
+; CHECK-NEXT: store i32 12, i32* @X
+; CHECK-NEXT: call void @modrefXatomicrmw()
+; CHECK-NEXT: %V = load i32, i32* @X
+; CHECK-NEXT: ret i32 %V
+  store i32 12, i32* @X
+  call void @modrefXatomicrmw()
+  %V = load i32, i32* @X
+  ret i32 %V
+}
+
+define void @modrefXatomicrmw() {
+  %1 = atomicrmw add i32* @X, i32 1 acquire
+  ret void
+}