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diff --git a/lib/Target/SystemZ/SystemZCallingConv.td b/lib/Target/SystemZ/SystemZCallingConv.td
new file mode 100644
index 0000000000..c2d727fe4d
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+++ b/lib/Target/SystemZ/SystemZCallingConv.td
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+//=- SystemZCallingConv.td - Calling conventions for SystemZ -*- tablegen -*-=//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// This describes the calling conventions for the SystemZ ABI.
+//===----------------------------------------------------------------------===//
+
+class CCIfExtend<CCAction A>
+  : CCIf<"ArgFlags.isSExt() || ArgFlags.isZExt()", A>;
+
+//===----------------------------------------------------------------------===//
+// SVR4 return value calling convention
+//===----------------------------------------------------------------------===//
+def RetCC_SystemZ : CallingConv<[
+  // Promote i32 to i64 if it has an explicit extension type.
+  CCIfType<[i32], CCIfExtend<CCPromoteToType<i64>>>,
+
+  // ABI-compliant code returns 64-bit integers in R2.  Make the other
+  // call-clobbered argument registers available for code that doesn't
+  // care about the ABI.  (R6 is an argument register too, but is
+  // call-saved and therefore not suitable for return values.)
+  CCIfType<[i32], CCAssignToReg<[R2W, R3W, R4W, R5W]>>,
+  CCIfType<[i64], CCAssignToReg<[R2D, R3D, R4D, R5D]>>,
+
+  // ABI-complaint code returns float and double in F0.  Make the
+  // other floating-point argument registers available for code that
+  // doesn't care about the ABI.  All floating-point argument registers
+  // are call-clobbered, so we can use all of them here.
+  CCIfType<[f32], CCAssignToReg<[F0S, F2S, F4S, F6S]>>,
+  CCIfType<[f64], CCAssignToReg<[F0D, F2D, F4D, F6D]>>
+
+  // ABI-compliant code returns long double by reference, but that conversion
+  // is left to higher-level code.  Perhaps we could add an f128 definition
+  // here for code that doesn't care about the ABI?
+]>;
+
+//===----------------------------------------------------------------------===//
+// SVR4 argument calling conventions
+//===----------------------------------------------------------------------===//
+def CC_SystemZ : CallingConv<[
+  // Promote i32 to i64 if it has an explicit extension type.
+  // The convention is that true integer arguments that are smaller
+  // than 64 bits should be marked as extended, but structures that
+  // are smaller than 64 bits shouldn't.
+  CCIfType<[i32], CCIfExtend<CCPromoteToType<i64>>>,
+
+  // Force long double values to the stack and pass i64 pointers to them.
+  CCIfType<[f128], CCPassIndirect<i64>>,
+
+  // The first 5 integer arguments are passed in R2-R6.  Note that R6
+  // is call-saved.
+  CCIfType<[i32], CCAssignToReg<[R2W, R3W, R4W, R5W, R6W]>>,
+  CCIfType<[i64], CCAssignToReg<[R2D, R3D, R4D, R5D, R6D]>>,
+
+  // The first 4 float and double arguments are passed in even registers F0-F6.
+  CCIfType<[f32], CCAssignToReg<[F0S, F2S, F4S, F6S]>>,
+  CCIfType<[f64], CCAssignToReg<[F0D, F2D, F4D, F6D]>>,
+
+  // Other arguments are passed in 8-byte-aligned 8-byte stack slots.
+  CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 8>>
+]>;