1//===-- AVRCallingConv.td - Calling Conventions for AVR ----*- tablegen -*-===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8// This describes the calling conventions for AVR architecture. 9//===----------------------------------------------------------------------===// 10 11//===----------------------------------------------------------------------===// 12// AVR Return Value Calling Convention 13//===----------------------------------------------------------------------===// 14 15def RetCC_AVR : CallingConv 16<[ 17 // i8 is returned in R24. 18 CCIfType<[i8], CCAssignToReg<[R24]>>, 19 20 // i16 are returned in R25:R24, R23:R22, R21:R20 and R19:R18. 21 CCIfType<[i16], CCAssignToReg<[R25R24, R23R22, R21R20, R19R18]>> 22]>; 23 24// Special return value calling convention for runtime functions. 25def RetCC_AVR_BUILTIN : CallingConv 26<[ 27 CCIfType<[i8], CCAssignToReg<[R24,R25]>>, 28 CCIfType<[i16], CCAssignToReg<[R23R22, R25R24]>> 29]>; 30 31//===----------------------------------------------------------------------===// 32// AVR Argument Calling Conventions 33//===----------------------------------------------------------------------===// 34 35// The calling conventions are implemented in custom C++ code 36 37// Calling convention for variadic functions. 38def ArgCC_AVR_Vararg : CallingConv 39<[ 40 // i16 are always passed through the stack with an alignment of 1. 41 CCAssignToStack<2, 1> 42]>; 43 44// Special argument calling convention for 45// division runtime functions. 46def ArgCC_AVR_BUILTIN_DIV : CallingConv 47<[ 48 CCIfType<[i8], CCAssignToReg<[R24,R22]>>, 49 CCIfType<[i16], CCAssignToReg<[R25R24, R23R22]>> 50]>; 51 52//===----------------------------------------------------------------------===// 53// Callee-saved register lists. 54//===----------------------------------------------------------------------===// 55 56def CSR_Normal : CalleeSavedRegs<(add R29, R28, (sequence "R%u", 17, 2))>; 57def CSR_Interrupts : CalleeSavedRegs<(add (sequence "R%u", 31, 0))>; 58