From a8c897c57ca21b641560e1d0bc40f32ba9c9b23e Mon Sep 17 00:00:00 2001
From: Dylan McKay <dylanmckay34@gmail.com>
Date: Sun, 20 Dec 2015 23:17:44 +0000
Subject: [PATCH] [AVR] Added AVRCallingConv.td

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256130 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/AVR/AVR.td            |  2 +-
 lib/Target/AVR/AVRCallingConv.td | 65 ++++++++++++++++++++++++++++++++
 lib/Target/AVR/CMakeLists.txt    |  1 +
 3 files changed, 67 insertions(+), 1 deletion(-)
 create mode 100644 lib/Target/AVR/AVRCallingConv.td

diff --git a/lib/Target/AVR/AVR.td b/lib/Target/AVR/AVR.td
index ba59c8f42db..9e80717cd68 100644
--- a/lib/Target/AVR/AVR.td
+++ b/lib/Target/AVR/AVR.td
@@ -522,7 +522,7 @@ include "AVRRegisterInfo.td"
 // Calling Conventions
 //===---------------------------------------------------------------------===//
 
-//include "AVRCallingConv.td"
+include "AVRCallingConv.td"
 
 //===---------------------------------------------------------------------===//
 // Assembly Printers
diff --git a/lib/Target/AVR/AVRCallingConv.td b/lib/Target/AVR/AVRCallingConv.td
new file mode 100644
index 00000000000..d8cb3fe8402
--- /dev/null
+++ b/lib/Target/AVR/AVRCallingConv.td
@@ -0,0 +1,65 @@
+//===-- AVRCallingConv.td - Calling Conventions for AVR ----*- 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 AVR architecture.
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+// AVR Return Value Calling Convention
+//===----------------------------------------------------------------------===//
+
+def RetCC_AVR : CallingConv
+<[
+  // i8 is returned in R24.
+  CCIfType<[i8], CCAssignToReg<[R24]>>,
+
+  // i16 are returned in R25:R24, R23:R22, R21:R20 and R19:R18.
+  CCIfType<[i16], CCAssignToReg<[R25R24, R23R22, R21R20, R19R18]>>
+]>;
+
+// Special return value calling convention for runtime functions.
+def RetCC_AVR_RT : CallingConv
+<[
+  CCIfType<[i8], CCAssignToReg<[R24,R25]>>,
+  CCIfType<[i16], CCAssignToReg<[R23R22, R25R24]>>
+]>;
+
+//===----------------------------------------------------------------------===//
+// AVR Argument Calling Conventions
+//===----------------------------------------------------------------------===//
+
+// The calling conventions are implemented in custom C++ code
+
+// Calling convention for variadic functions.
+def ArgCC_AVR_Vararg : CallingConv
+<[
+  // i16 are always passed through the stack with an alignment of 1.
+  CCAssignToStack<2, 1>
+]>;
+
+// Special argument calling convention for
+// multiplication runtime functions.
+def ArgCC_AVR_RT_MUL : CallingConv
+<[
+  CCIfType<[i16], CCAssignToReg<[R27R26,R19R18]>>
+]>;
+
+// Special argument calling convention for
+// division runtime functions.
+def ArgCC_AVR_RT_DIV : CallingConv
+<[
+  CCIfType<[i8], CCAssignToReg<[R24,R22]>>,
+  CCIfType<[i16], CCAssignToReg<[R25R24, R23R22]>>
+]>;
+
+//===----------------------------------------------------------------------===//
+// Callee-saved register lists.
+//===----------------------------------------------------------------------===//
+
+def CSR_Normal : CalleeSavedRegs<(add R29, R28, (sequence "R%u", 17, 2))>;
+def CSR_Interrupts : CalleeSavedRegs<(add (sequence "R%u", 31, 0))>;
diff --git a/lib/Target/AVR/CMakeLists.txt b/lib/Target/AVR/CMakeLists.txt
index 9c29f2086e6..22b30ef3585 100644
--- a/lib/Target/AVR/CMakeLists.txt
+++ b/lib/Target/AVR/CMakeLists.txt
@@ -1,6 +1,7 @@
 set(LLVM_TARGET_DEFINITIONS AVR.td)
 
 tablegen(LLVM AVRGenRegisterInfo.inc -gen-register-info)
+tablegen(LLVM AVRGenCallingConv.inc -gen-callingconv)
 add_public_tablegen_target(AVRCommonTableGen)
 
 add_llvm_target(AVRCodeGen
-- 
2.34.1