Mips16RegisterInfo.cpp revision 24e79e55daa5d2812d2a5ea0a282ebe48ef465e6
1//===-- Mips16RegisterInfo.cpp - MIPS16 Register Information -== ----------===// 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// 10// This file contains the MIPS16 implementation of the TargetRegisterInfo class. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Mips16RegisterInfo.h" 15#include "Mips.h" 16#include "MipsAnalyzeImmediate.h" 17#include "MipsInstrInfo.h" 18#include "MipsSubtarget.h" 19#include "MipsMachineFunction.h" 20#include "llvm/Constants.h" 21#include "llvm/DebugInfo.h" 22#include "llvm/Type.h" 23#include "llvm/Function.h" 24#include "llvm/CodeGen/ValueTypes.h" 25#include "llvm/CodeGen/MachineInstrBuilder.h" 26#include "llvm/CodeGen/MachineFunction.h" 27#include "llvm/CodeGen/MachineFrameInfo.h" 28#include "llvm/Target/TargetFrameLowering.h" 29#include "llvm/Target/TargetMachine.h" 30#include "llvm/Target/TargetOptions.h" 31#include "llvm/Target/TargetInstrInfo.h" 32#include "llvm/Support/CommandLine.h" 33#include "llvm/Support/Debug.h" 34#include "llvm/Support/ErrorHandling.h" 35#include "llvm/Support/raw_ostream.h" 36#include "llvm/ADT/BitVector.h" 37#include "llvm/ADT/STLExtras.h" 38 39using namespace llvm; 40 41Mips16RegisterInfo::Mips16RegisterInfo(const MipsSubtarget &ST, 42 const TargetInstrInfo &TII) 43 : MipsRegisterInfo(ST, TII) {} 44 45// This function eliminate ADJCALLSTACKDOWN, 46// ADJCALLSTACKUP pseudo instructions 47void Mips16RegisterInfo:: 48eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, 49 MachineBasicBlock::iterator I) const { 50 // Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions. 51 MBB.erase(I); 52} 53 54void Mips16RegisterInfo::eliminateFI(MachineBasicBlock::iterator II, 55 unsigned OpNo, int FrameIndex, 56 uint64_t StackSize, 57 int64_t SPOffset) const { 58 MachineInstr &MI = *II; 59 MachineFunction &MF = *MI.getParent()->getParent(); 60 MachineFrameInfo *MFI = MF.getFrameInfo(); 61 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>(); 62 63 const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo(); 64 int MinCSFI = 0; 65 int MaxCSFI = -1; 66 67 if (CSI.size()) { 68 MinCSFI = CSI[0].getFrameIdx(); 69 MaxCSFI = CSI[CSI.size() - 1].getFrameIdx(); 70 } 71 72 // The following stack frame objects are always 73 // referenced relative to $sp: 74 // 1. Outgoing arguments. 75 // 2. Pointer to dynamically allocated stack space. 76 // 3. Locations for callee-saved registers. 77 // Everything else is referenced relative to whatever register 78 // getFrameRegister() returns. 79 unsigned FrameReg; 80 81 if (MipsFI->isOutArgFI(FrameIndex) || 82 (FrameIndex >= MinCSFI && FrameIndex <= MaxCSFI)) 83 FrameReg = Subtarget.isABI_N64() ? Mips::SP_64 : Mips::SP; 84 else 85 FrameReg = getFrameRegister(MF); 86 87 // Calculate final offset. 88 // - There is no need to change the offset if the frame object 89 // is one of the 90 // following: an outgoing argument, pointer to a dynamically allocated 91 // stack space or a $gp restore location, 92 // - If the frame object is any of the following, 93 // its offset must be adjusted 94 // by adding the size of the stack: 95 // incoming argument, callee-saved register location or local variable. 96 int64_t Offset; 97 98 if (MipsFI->isOutArgFI(FrameIndex)) 99 Offset = SPOffset; 100 else 101 Offset = SPOffset + (int64_t)StackSize; 102 103 Offset += MI.getOperand(OpNo + 1).getImm(); 104 105 DEBUG(errs() << "Offset : " << Offset << "\n" << "<--------->\n"); 106 107 MI.getOperand(OpNo).ChangeToRegister(FrameReg, false); 108 MI.getOperand(OpNo + 1).ChangeToImmediate(Offset); 109 110 111} 112