1 //===- MipsRegisterInfo.cpp - MIPS Register Information -== -----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the MIPS implementation of the TargetRegisterInfo class.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "mips-reg-info"
17 #include "MipsSubtarget.h"
18 #include "MipsRegisterInfo.h"
19 #include "MipsMachineFunction.h"
20 #include "llvm/Constants.h"
21 #include "llvm/Type.h"
22 #include "llvm/Function.h"
23 #include "llvm/CodeGen/ValueTypes.h"
24 #include "llvm/CodeGen/MachineInstrBuilder.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineFrameInfo.h"
27 #include "llvm/CodeGen/MachineLocation.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"
41 MipsRegisterInfo::MipsRegisterInfo(const MipsSubtarget &ST,
42 const TargetInstrInfo &tii)
43 : MipsGenRegisterInfo(Mips::ADJCALLSTACKDOWN, Mips::ADJCALLSTACKUP),
44 Subtarget(ST), TII(tii) {}
46 /// getRegisterNumbering - Given the enum value for some register, e.g.
47 /// Mips::RA, return the number that it corresponds to (e.g. 31).
48 unsigned MipsRegisterInfo::
49 getRegisterNumbering(unsigned RegEnum)
52 case Mips::ZERO : case Mips::F0 : case Mips::D0 : return 0;
53 case Mips::AT : case Mips::F1 : return 1;
54 case Mips::V0 : case Mips::F2 : case Mips::D1 : return 2;
55 case Mips::V1 : case Mips::F3 : return 3;
56 case Mips::A0 : case Mips::F4 : case Mips::D2 : return 4;
57 case Mips::A1 : case Mips::F5 : return 5;
58 case Mips::A2 : case Mips::F6 : case Mips::D3 : return 6;
59 case Mips::A3 : case Mips::F7 : return 7;
60 case Mips::T0 : case Mips::F8 : case Mips::D4 : return 8;
61 case Mips::T1 : case Mips::F9 : return 9;
62 case Mips::T2 : case Mips::F10: case Mips::D5: return 10;
63 case Mips::T3 : case Mips::F11: return 11;
64 case Mips::T4 : case Mips::F12: case Mips::D6: return 12;
65 case Mips::T5 : case Mips::F13: return 13;
66 case Mips::T6 : case Mips::F14: case Mips::D7: return 14;
67 case Mips::T7 : case Mips::F15: return 15;
68 case Mips::S0 : case Mips::F16: case Mips::D8: return 16;
69 case Mips::S1 : case Mips::F17: return 17;
70 case Mips::S2 : case Mips::F18: case Mips::D9: return 18;
71 case Mips::S3 : case Mips::F19: return 19;
72 case Mips::S4 : case Mips::F20: case Mips::D10: return 20;
73 case Mips::S5 : case Mips::F21: return 21;
74 case Mips::S6 : case Mips::F22: case Mips::D11: return 22;
75 case Mips::S7 : case Mips::F23: return 23;
76 case Mips::T8 : case Mips::F24: case Mips::D12: return 24;
77 case Mips::T9 : case Mips::F25: return 25;
78 case Mips::K0 : case Mips::F26: case Mips::D13: return 26;
79 case Mips::K1 : case Mips::F27: return 27;
80 case Mips::GP : case Mips::F28: case Mips::D14: return 28;
81 case Mips::SP : case Mips::F29: return 29;
82 case Mips::FP : case Mips::F30: case Mips::D15: return 30;
83 case Mips::RA : case Mips::F31: return 31;
84 default: llvm_unreachable("Unknown register number!");
86 return 0; // Not reached
89 unsigned MipsRegisterInfo::getPICCallReg() { return Mips::T9; }
91 //===----------------------------------------------------------------------===//
92 // Callee Saved Registers methods
93 //===----------------------------------------------------------------------===//
95 /// Mips Callee Saved Registers
96 const unsigned* MipsRegisterInfo::
97 getCalleeSavedRegs(const MachineFunction *MF) const
99 // Mips callee-save register range is $16-$23, $f20-$f30
100 static const unsigned SingleFloatOnlyCalleeSavedRegs[] = {
101 Mips::S0, Mips::S1, Mips::S2, Mips::S3,
102 Mips::S4, Mips::S5, Mips::S6, Mips::S7,
103 Mips::F20, Mips::F21, Mips::F22, Mips::F23, Mips::F24, Mips::F25,
104 Mips::F26, Mips::F27, Mips::F28, Mips::F29, Mips::F30, 0
107 static const unsigned BitMode32CalleeSavedRegs[] = {
108 Mips::S0, Mips::S1, Mips::S2, Mips::S3,
109 Mips::S4, Mips::S5, Mips::S6, Mips::S7,
110 Mips::F20, Mips::F22, Mips::F24, Mips::F26, Mips::F28, Mips::F30, 0
113 if (Subtarget.isSingleFloat())
114 return SingleFloatOnlyCalleeSavedRegs;
116 return BitMode32CalleeSavedRegs;
119 BitVector MipsRegisterInfo::
120 getReservedRegs(const MachineFunction &MF) const {
121 BitVector Reserved(getNumRegs());
122 Reserved.set(Mips::ZERO);
123 Reserved.set(Mips::AT);
124 Reserved.set(Mips::K0);
125 Reserved.set(Mips::K1);
126 Reserved.set(Mips::GP);
127 Reserved.set(Mips::SP);
128 Reserved.set(Mips::FP);
129 Reserved.set(Mips::RA);
131 // SRV4 requires that odd register can't be used.
132 if (!Subtarget.isSingleFloat())
133 for (unsigned FReg=(Mips::F0)+1; FReg < Mips::F30; FReg+=2)
139 // This function eliminate ADJCALLSTACKDOWN,
140 // ADJCALLSTACKUP pseudo instructions
141 void MipsRegisterInfo::
142 eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
143 MachineBasicBlock::iterator I) const {
144 // Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions.
148 // FrameIndex represent objects inside a abstract stack.
149 // We must replace FrameIndex with an stack/frame pointer
151 void MipsRegisterInfo::
152 eliminateFrameIndex(MachineBasicBlock::iterator II, int SPAdj,
153 RegScavenger *RS) const {
154 MachineInstr &MI = *II;
155 MachineFunction &MF = *MI.getParent()->getParent();
158 while (!MI.getOperand(i).isFI()) {
160 assert(i < MI.getNumOperands() &&
161 "Instr doesn't have FrameIndex operand!");
164 DEBUG(errs() << "\nFunction : " << MF.getFunction()->getName() << "\n";
165 errs() << "<--------->\n" << MI);
167 int FrameIndex = MI.getOperand(i).getIndex();
168 int stackSize = MF.getFrameInfo()->getStackSize();
169 int spOffset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
171 DEBUG(errs() << "FrameIndex : " << FrameIndex << "\n"
172 << "spOffset : " << spOffset << "\n"
173 << "stackSize : " << stackSize << "\n");
175 // as explained on LowerFormalArguments, detect negative offsets
176 // and adjust SPOffsets considering the final stack size.
177 int Offset = ((spOffset < 0) ? (stackSize + (-(spOffset+4))) : (spOffset));
178 Offset += MI.getOperand(i-1).getImm();
180 DEBUG(errs() << "Offset : " << Offset << "\n" << "<--------->\n");
184 MachineBasicBlock &MBB = *MI.getParent();
186 unsigned OrigReg = getFrameRegister(MF);
187 int OrigImm = Offset;
189 // OrigImm fits in the 16-bit field
190 if (OrigImm < 0x8000 && OrigImm >= -0x8000) {
196 const TargetInstrInfo *TII = MF.getTarget().getInstrInfo();
197 DebugLoc DL = II->getDebugLoc();
198 int ImmLo = OrigImm & 0xffff;
199 int ImmHi = (((unsigned)OrigImm & 0xffff0000) >> 16) +
200 ((OrigImm & 0x8000) != 0);
202 // FIXME: change this when mips goes MC".
203 BuildMI(MBB, II, DL, TII->get(Mips::NOAT));
204 BuildMI(MBB, II, DL, TII->get(Mips::LUi), Mips::AT).addImm(ImmHi);
205 BuildMI(MBB, II, DL, TII->get(Mips::ADDu), Mips::AT).addReg(OrigReg)
213 // FIXME: change this when mips goes MC".
215 BuildMI(MBB, ++II, MI.getDebugLoc(), TII.get(Mips::ATMACRO));
217 MI.getOperand(i).ChangeToRegister(NewReg, false);
218 MI.getOperand(i-1).ChangeToImmediate(NewImm);
221 void MipsRegisterInfo::
222 processFunctionBeforeFrameFinalized(MachineFunction &MF) const {
223 // Set the stack offset where GP must be saved/loaded from.
224 MachineFrameInfo *MFI = MF.getFrameInfo();
225 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
226 if (MipsFI->needGPSaveRestore())
227 MFI->setObjectOffset(MipsFI->getGPFI(), MipsFI->getGPStackOffset());
230 unsigned MipsRegisterInfo::
231 getRARegister() const {
235 unsigned MipsRegisterInfo::
236 getFrameRegister(const MachineFunction &MF) const {
237 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
239 return TFI->hasFP(MF) ? Mips::FP : Mips::SP;
242 unsigned MipsRegisterInfo::
243 getEHExceptionRegister() const {
244 llvm_unreachable("What is the exception register");
248 unsigned MipsRegisterInfo::
249 getEHHandlerRegister() const {
250 llvm_unreachable("What is the exception handler register");
254 int MipsRegisterInfo::
255 getDwarfRegNum(unsigned RegNum, bool isEH) const {
256 llvm_unreachable("What is the dwarf register number");
260 #include "MipsGenRegisterInfo.inc"