llvm-project/llvm/lib/Target/AVR/AVRCallingConv.td

58 lines
2.1 KiB
TableGen

//===-- AVRCallingConv.td - Calling Conventions for AVR ----*- tablegen -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// 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_BUILTIN : 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
// division runtime functions.
def ArgCC_AVR_BUILTIN_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))>;