1 files changed, 31 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/X86/x86-no_caller_saved_registers.ll b/llvm/test/CodeGen/X86/x86-no_caller_saved_registers.ll
new file mode 100644
index 00000000000..9c62e3ee6ba
--- /dev/null
+++ b/llvm/test/CodeGen/X86/x86-no_caller_saved_registers.ll
@@ -0,0 +1,31 @@
+; RUN: llc -mtriple=x86_64-unknown-unknown < %s | FileCheck %s
+; RUN: llc -mtriple=x86_64-unknown-unknown -O0 < %s | FileCheck %s
+; RUN: llc -mtriple=i686-unknown-unknown -mattr=+sse2 < %s | FileCheck %s
+; RUN: llc -mtriple=i686-unknown-unknown -mattr=+sse2 -O0 < %s | FileCheck %s
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; In functions with 'no_caller_saved_registers' attribute, all registers should
+;; be preserved except for registers used for passing/returning arguments.
+;; The test checks that function "bar" preserves xmm0 register.
+;; It also checks that caller function "foo" does not store registers for callee 
+;; "bar". For example, there is no store/load/access to xmm registers.
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+define i32 @bar(i32 %a0, i32 %a1, i32 %a2, i32 %a3, i32 %a4, i32 %a5, i32 %a6, i32 %a7, i32 %a8) #0 {
+; CHECK-LABEL: bar
+; CHECK:       mov{{.*}}  %xmm0
+; CHECK:       mov{{.*}} {{.*}}, %xmm0
+; CHECK:       ret
+  call void asm sideeffect "", "~{xmm0}"()
+  ret i32 1
+}
+
+define x86_intrcc void @foo(i8* nocapture readnone %c) {
+; CHECK-LABEL: foo
+; CHECK-NOT: xmm
+entry:
+  tail call i32 @bar(i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8) #0
+  ret void
+}
+
+attributes #0 = { "no_caller_saved_registers" }