1 files changed, 71 insertions, 0 deletions
diff --git a/test/Feature/OperandBundles/early-cse.ll b/test/Feature/OperandBundles/early-cse.ll
new file mode 100644
index 00000000000..076ce3baeab
--- /dev/null
+++ b/test/Feature/OperandBundles/early-cse.ll
@@ -0,0 +1,71 @@
+; RUN: opt -S -early-cse < %s | FileCheck %s
+
+; While it is normally okay to do memory optimizations over calls to
+; @readonly_function and @readnone_function, we cannot do that if
+; they're carrying operand bundles since the presence of unknown
+; operand bundles implies arbitrary memory effects.
+
+declare void @readonly_function() readonly nounwind
+declare void @readnone_function() readnone nounwind
+
+define i32 @test0(i32* %x) {
+; CHECK-LABEL: @test0(
+ entry:
+  store i32 100, i32* %x
+; CHECK: store i32 100, i32* %x
+  call void @readonly_function() [ "tag"() ]
+; CHECK: call void @readonly_function()
+
+  %v = load i32, i32* %x
+; CHECK: %v = load i32, i32* %x
+; CHECK: ret i32 %v
+  ret i32 %v
+}
+
+define i32 @test1(i32* %x) {
+; CHECK: @test1(
+ entry:
+  store i32 100, i32* %x
+; CHECK: store i32 100, i32* %x
+  call void @readonly_function() readonly [ "tag"() ]
+; CHECK-NOT: call void @readonly_function
+  %v = load i32, i32* %x
+  ret i32 %v
+; CHECK: ret i32 100
+}
+
+define i32 @test3(i32* %x) {
+; CHECK-LABEL: @test3(
+ entry:
+  store i32 100, i32* %x
+; CHECK: store i32 100, i32* %x
+  call void @readonly_function()
+; CHECK-NOT: call void @readonly_function
+  %v = load i32, i32* %x
+  ret i32 %v
+; CHECK: ret i32 100
+}
+
+define void @test4(i32* %x) {
+; CHECK-LABEL: @test4(
+ entry:
+  store i32 100, i32* %x
+; CHECK: store i32 100, i32* %x
+  call void @readnone_function() [ "tag"() ]
+; CHECK: call void @readnone_function
+  store i32 200, i32* %x
+; CHECK: store i32 200, i32* %x
+  ret void
+}
+
+define void @test5(i32* %x) {
+; CHECK-LABEL: @test5(
+ entry:
+  store i32 100, i32* %x
+; CHECK-NOT: store i32 100, i32* %x
+; CHECK-NOT: call void @readnone_function
+  call void @readnone_function() readnone [ "tag"() ]
+  store i32 200, i32* %x
+; CHECK: store i32 200, i32* %x
+  ret void
+}