1 //===-- AVRCallingConv.td - Calling Conventions for AVR ----*- tablegen -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // This describes the calling conventions for AVR architecture. 10 //===----------------------------------------------------------------------===// 11 12 //===----------------------------------------------------------------------===// 13 // AVR Return Value Calling Convention 14 //===----------------------------------------------------------------------===// 15 16 def RetCC_AVR : CallingConv 17 <[ 18 // i8 is returned in R24. 19 CCIfType<[i8], CCAssignToReg<[R24]>>, 20 21 // i16 are returned in R25:R24, R23:R22, R21:R20 and R19:R18. 22 CCIfType<[i16], CCAssignToReg<[R25R24, R23R22, R21R20, R19R18]>> 23 ]>; 24 25 // Special return value calling convention for runtime functions. 26 def RetCC_AVR_RT : CallingConv 27 <[ 28 CCIfType<[i8], CCAssignToReg<[R24,R25]>>, 29 CCIfType<[i16], CCAssignToReg<[R23R22, R25R24]>> 30 ]>; 31 32 //===----------------------------------------------------------------------===// 33 // AVR Argument Calling Conventions 34 //===----------------------------------------------------------------------===// 35 36 // The calling conventions are implemented in custom C++ code 37 38 // Calling convention for variadic functions. 39 def ArgCC_AVR_Vararg : CallingConv 40 <[ 41 // i16 are always passed through the stack with an alignment of 1. 42 CCAssignToStack<2, 1> 43 ]>; 44 45 // Special argument calling convention for 46 // multiplication runtime functions. 47 def ArgCC_AVR_RT_MUL : CallingConv 48 <[ 49 CCIfType<[i16], CCAssignToReg<[R27R26,R19R18]>> 50 ]>; 51 52 // Special argument calling convention for 53 // division runtime functions. 54 def ArgCC_AVR_RT_DIV : CallingConv 55 <[ 56 CCIfType<[i8], CCAssignToReg<[R24,R22]>>, 57 CCIfType<[i16], CCAssignToReg<[R25R24, R23R22]>> 58 ]>; 59 60 //===----------------------------------------------------------------------===// 61 // Callee-saved register lists. 62 //===----------------------------------------------------------------------===// 63 64 def CSR_Normal : CalleeSavedRegs<(add R29, R28, (sequence "R%u", 17, 2))>; 65 def CSR_Interrupts : CalleeSavedRegs<(add (sequence "R%u", 31, 0))>; 66
