1 files changed, 66 insertions, 0 deletions
diff --git a/test/CodeGen/SystemZ/swiftself.ll b/test/CodeGen/SystemZ/swiftself.ll
new file mode 100644
index 0000000000000..ee6104ad20398
--- /dev/null
+++ b/test/CodeGen/SystemZ/swiftself.ll
@@ -0,0 +1,66 @@
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+; Parameter with swiftself should be allocated to r10.
+; CHECK-LABEL: swiftself_param:
+; CHECK: lgr %r2, %r10
+define i8 *@swiftself_param(i8* swiftself %addr0) {
+  ret i8 *%addr0
+}
+
+; Check that r10 is used to pass a swiftself argument.
+; CHECK-LABEL: call_swiftself:
+; CHECK: lgr %r10, %r2
+; CHECK: brasl %r14, swiftself_param
+define i8 *@call_swiftself(i8* %arg) {
+  %res = call i8 *@swiftself_param(i8* swiftself %arg)
+  ret i8 *%res
+}
+
+; r10 should be saved by the callee even if used for swiftself
+; CHECK-LABEL: swiftself_clobber:
+; CHECK: stmg %r10,
+; ...
+; CHECK: lmg %r10,
+; CHECK: br %r14
+define i8 *@swiftself_clobber(i8* swiftself %addr0) {
+  call void asm sideeffect "", "~{r10}"()
+  ret i8 *%addr0
+}
+
+; Demonstrate that we do not need any loads when calling multiple functions
+; with swiftself argument.
+; CHECK-LABEL: swiftself_passthrough:
+; CHECK-NOT: lg{{.*}}r10,
+; CHECK: brasl %r14, swiftself_param
+; CHECK-NOT: lg{{.*}}r10,
+; CHECK-NEXT: brasl %r14, swiftself_param
+define void @swiftself_passthrough(i8* swiftself %addr0) {
+  call i8 *@swiftself_param(i8* swiftself %addr0)
+  call i8 *@swiftself_param(i8* swiftself %addr0)
+  ret void
+}
+
+; Normally, we can use a tail call if the callee swiftself is the same as the
+; caller one. Not yet supported on SystemZ.
+; CHECK-LABEL: swiftself_tail:
+; CHECK: lgr %r[[REG1:[0-9]+]], %r10
+; CHECK: lgr %r10, %r[[REG1]]
+; CHECK: brasl %r14, swiftself_param
+; CHECK: br %r14
+define i8* @swiftself_tail(i8* swiftself %addr0) {
+  call void asm sideeffect "", "~{r10}"()
+  %res = tail call i8* @swiftself_param(i8* swiftself %addr0)
+  ret i8* %res
+}
+
+; We can not use a tail call if the callee swiftself is not the same as the
+; caller one.
+; CHECK-LABEL: swiftself_notail:
+; CHECK: lgr %r10, %r2
+; CHECK: brasl %r14, swiftself_param
+; CHECK: lmg %r10,
+; CHECK: br %r14
+define i8* @swiftself_notail(i8* swiftself %addr0, i8* %addr1) nounwind {
+  %res = tail call i8* @swiftself_param(i8* swiftself %addr1)
+  ret i8* %res
+}