diff --git a/llvm/lib/Target/X86/X86CallingConv.td b/llvm/lib/Target/X86/X86CallingConv.td
index 4cb62b56bce4..d38145e5519f 100644
--- a/llvm/lib/Target/X86/X86CallingConv.td
+++ b/llvm/lib/Target/X86/X86CallingConv.td
@@ -196,6 +196,9 @@ def RetCC_X86_64_WebKit_JS : CallingConv<[
 ]>;
 
 def RetCC_X86_64_Swift : CallingConv<[
+
+  CCIfSwiftError<CCIfType<[i64], CCAssignToReg<[R12]>>>,
+
   // For integers, ECX, R8D can be used as extra return registers.
   CCIfType<[i1],  CCPromoteToType<i8>>,
   CCIfType<[i8] , CCAssignToReg<[AL, DL, CL, R8B]>>,
diff --git a/llvm/test/CodeGen/X86/swifterror.ll b/llvm/test/CodeGen/X86/swifterror.ll
index 46dc1778bdc6..21695cbc0036 100644
--- a/llvm/test/CodeGen/X86/swifterror.ll
+++ b/llvm/test/CodeGen/X86/swifterror.ll
@@ -376,3 +376,25 @@ entry:
 
   ret void
 }
+
+; This tests the basic usage of a swifterror parameter with swiftcc.
+define swiftcc float @foo_swiftcc(%swift_error** swifterror %error_ptr_ref) {
+; CHECK-APPLE-LABEL: foo_swiftcc:
+; CHECK-APPLE: movl $16, %edi
+; CHECK-APPLE: malloc
+; CHECK-APPLE: movb $1, 8(%rax)
+; CHECK-APPLE: movq %rax, %r12
+
+; CHECK-O0-LABEL: foo_swiftcc:
+; CHECK-O0: movl $16
+; CHECK-O0: malloc
+; CHECK-O0: movb $1, 8(%rax)
+; CHECK-O0: movq %{{.*}}, %r12
+entry:
+  %call = call i8* @malloc(i64 16)
+  %call.0 = bitcast i8* %call to %swift_error*
+  store %swift_error* %call.0, %swift_error** %error_ptr_ref
+  %tmp = getelementptr inbounds i8, i8* %call, i64 8
+  store i8 1, i8* %tmp
+  ret float 1.0
+}