1 //===- PPC32RegisterInfo.cpp - PowerPC32 Register Information ---*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the PowerPC32 implementation of the MRegisterInfo class.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "reginfo"
16 #include "PowerPCInstrBuilder.h"
17 #include "PPC32RegisterInfo.h"
18 #include "llvm/Constants.h"
19 #include "llvm/Type.h"
20 #include "llvm/CodeGen/ValueTypes.h"
21 #include "llvm/CodeGen/MachineInstrBuilder.h"
22 #include "llvm/CodeGen/MachineFunction.h"
23 #include "llvm/CodeGen/MachineFrameInfo.h"
24 #include "llvm/Target/TargetFrameInfo.h"
25 #include "llvm/Target/TargetMachine.h"
26 #include "llvm/Target/TargetOptions.h"
27 #include "Support/CommandLine.h"
28 #include "Support/Debug.h"
29 #include "Support/STLExtras.h"
35 // Switch toggling compilation for AIX
36 extern cl::opt<bool> AIX;
39 PPC32RegisterInfo::PPC32RegisterInfo()
40 : PPC32GenRegisterInfo(PPC::ADJCALLSTACKDOWN, PPC::ADJCALLSTACKUP) {
41 ImmToIdxMap[PPC::LD] = PPC::LDX; ImmToIdxMap[PPC::STD] = PPC::STDX;
42 ImmToIdxMap[PPC::LBZ] = PPC::LBZX; ImmToIdxMap[PPC::STB] = PPC::STBX;
43 ImmToIdxMap[PPC::LHZ] = PPC::LHZX; ImmToIdxMap[PPC::LHA] = PPC::LHAX;
44 ImmToIdxMap[PPC::LWZ] = PPC::LWZX; ImmToIdxMap[PPC::LWA] = PPC::LWAX;
45 ImmToIdxMap[PPC::LFS] = PPC::LFSX; ImmToIdxMap[PPC::LFD] = PPC::LFDX;
46 ImmToIdxMap[PPC::STH] = PPC::STHX; ImmToIdxMap[PPC::STW] = PPC::STWX;
47 ImmToIdxMap[PPC::STFS] = PPC::STFSX; ImmToIdxMap[PPC::STFD] = PPC::STFDX;
48 ImmToIdxMap[PPC::ADDI] = PPC::ADD;
51 static unsigned getIdx(const TargetRegisterClass *RC) {
52 if (RC == PPC32::GPRCRegisterClass) {
53 switch (RC->getSize()) {
54 default: assert(0 && "Invalid data size!");
59 } else if (RC == PPC32::FPRCRegisterClass) {
60 switch (RC->getSize()) {
61 default: assert(0 && "Invalid data size!");
66 std::cerr << "Invalid register class to getIdx()!\n";
71 PPC32RegisterInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
72 MachineBasicBlock::iterator MI,
73 unsigned SrcReg, int FrameIdx) const {
74 const TargetRegisterClass *RC = getRegClass(SrcReg);
75 static const unsigned Opcode[] = {
76 PPC::STB, PPC::STH, PPC::STW, PPC::STFS, PPC::STFD
79 unsigned OC = Opcode[getIdx(RC)];
80 if (SrcReg == PPC::LR) {
81 BuildMI(MBB, MI, PPC::MFLR, 0, PPC::R11);
82 BuildMI(MBB, MI, PPC::IMPLICIT_DEF, 0, PPC::R0);
83 addFrameReference(BuildMI(MBB, MI, OC, 3).addReg(PPC::R11),FrameIdx);
85 BuildMI(MBB, MI, PPC::IMPLICIT_DEF, 0, PPC::R0);
86 addFrameReference(BuildMI(MBB, MI, OC, 3).addReg(SrcReg),FrameIdx);
91 PPC32RegisterInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
92 MachineBasicBlock::iterator MI,
93 unsigned DestReg, int FrameIdx) const{
94 static const unsigned Opcode[] = {
95 PPC::LBZ, PPC::LHZ, PPC::LWZ, PPC::LFS, PPC::LFD
97 const TargetRegisterClass *RC = getRegClass(DestReg);
98 unsigned OC = Opcode[getIdx(RC)];
99 if (DestReg == PPC::LR) {
100 BuildMI(MBB, MI, PPC::IMPLICIT_DEF, 0, PPC::R0);
101 addFrameReference(BuildMI(MBB, MI, OC, 2, PPC::R11), FrameIdx);
102 BuildMI(MBB, MI, PPC::MTLR, 1).addReg(PPC::R11);
104 BuildMI(MBB, MI, PPC::IMPLICIT_DEF, 0, PPC::R0);
105 addFrameReference(BuildMI(MBB, MI, OC, 2, DestReg), FrameIdx);
109 void PPC32RegisterInfo::copyRegToReg(MachineBasicBlock &MBB,
110 MachineBasicBlock::iterator MI,
111 unsigned DestReg, unsigned SrcReg,
112 const TargetRegisterClass *RC) const {
115 if (RC == PPC32::GPRCRegisterClass) {
116 BuildMI(MBB, MI, PPC::OR, 2, DestReg).addReg(SrcReg).addReg(SrcReg);
117 } else if (RC == PPC32::FPRCRegisterClass) {
118 BuildMI(MBB, MI, PPC::FMR, 1, DestReg).addReg(SrcReg);
120 std::cerr << "Attempt to copy register that is not GPR or FPR";
125 //===----------------------------------------------------------------------===//
126 // Stack Frame Processing methods
127 //===----------------------------------------------------------------------===//
129 // hasFP - Return true if the specified function should have a dedicated frame
130 // pointer register. This is true if the function has variable sized allocas or
131 // if frame pointer elimination is disabled.
133 static bool hasFP(MachineFunction &MF) {
134 MachineFrameInfo *MFI = MF.getFrameInfo();
135 return MFI->hasVarSizedObjects();
138 void PPC32RegisterInfo::
139 eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
140 MachineBasicBlock::iterator I) const {
142 // If we have a frame pointer, convert as follows:
143 // ADJCALLSTACKDOWN -> addi, r1, r1, -amount
144 // ADJCALLSTACKUP -> addi, r1, r1, amount
145 MachineInstr *Old = I;
146 unsigned Amount = Old->getOperand(0).getImmedValue();
148 // We need to keep the stack aligned properly. To do this, we round the
149 // amount of space needed for the outgoing arguments up to the next
150 // alignment boundary.
151 unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment();
152 Amount = (Amount+Align-1)/Align*Align;
154 // Replace the pseudo instruction with a new instruction...
155 if (Old->getOpcode() == PPC::ADJCALLSTACKDOWN) {
156 MBB.insert(I, BuildMI(PPC::ADDI, 2, PPC::R1).addReg(PPC::R1)
159 assert(Old->getOpcode() == PPC::ADJCALLSTACKUP);
160 MBB.insert(I, BuildMI(PPC::ADDI, 2, PPC::R1).addReg(PPC::R1)
169 PPC32RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const {
171 MachineInstr &MI = *II;
172 MachineBasicBlock &MBB = *MI.getParent();
173 MachineFunction &MF = *MBB.getParent();
175 while (!MI.getOperand(i).isFrameIndex()) {
177 assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
180 int FrameIndex = MI.getOperand(i).getFrameIndex();
182 // Replace the FrameIndex with base register with GPR1 (SP) or GPR31 (FP).
183 MI.SetMachineOperandReg(i, hasFP(MF) ? PPC::R31 : PPC::R1);
185 // Take into account whether it's an add or mem instruction
186 unsigned OffIdx = (i == 2) ? 1 : 2;
188 // Now add the frame object offset to the offset from r1.
189 int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
190 MI.getOperand(OffIdx).getImmedValue();
192 // If we're not using a Frame Pointer that has been set to the value of the
193 // SP before having the stack size subtracted from it, then add the stack size
194 // to Offset to get the correct offset.
195 Offset += MF.getFrameInfo()->getStackSize();
197 if (Offset > 32767 || Offset < -32768) {
198 // Insert a set of r0 with the full offset value before the ld, st, or add
199 MachineBasicBlock *MBB = MI.getParent();
200 MBB->insert(II, BuildMI(PPC::LIS, 1, PPC::R0).addSImm(Offset >> 16));
201 MBB->insert(II, BuildMI(PPC::ORI, 2, PPC::R0).addReg(PPC::R0)
203 // convert into indexed form of the instruction
204 // sth 0:rA, 1:imm 2:(rB) ==> sthx 0:rA, 2:rB, 1:r0
205 // addi 0:rA 1:rB, 2, imm ==> add 0:rA, 1:rB, 2:r0
206 unsigned NewOpcode = const_cast<std::map<unsigned, unsigned>& >(ImmToIdxMap)[MI.getOpcode()];
207 assert(NewOpcode && "No indexed form of load or store available!");
208 MI.setOpcode(NewOpcode);
209 MI.SetMachineOperandReg(1, MI.getOperand(i).getReg());
210 MI.SetMachineOperandReg(2, PPC::R0);
212 MI.SetMachineOperandConst(OffIdx,MachineOperand::MO_SignExtendedImmed,Offset);
217 void PPC32RegisterInfo::emitPrologue(MachineFunction &MF) const {
218 MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
219 MachineBasicBlock::iterator MBBI = MBB.begin();
220 MachineFrameInfo *MFI = MF.getFrameInfo();
223 // Get the number of bytes to allocate from the FrameInfo
224 unsigned NumBytes = MFI->getStackSize();
226 // If we have calls, we cannot use the red zone to store callee save registers
227 // and we must set up a stack frame, so calculate the necessary size here.
228 if (MFI->hasCalls()) {
229 // We reserve argument space for call sites in the function immediately on
230 // entry to the current function. This eliminates the need for add/sub
231 // brackets around call sites.
232 NumBytes += MFI->getMaxCallFrameSize();
235 // Do we need to allocate space on the stack?
236 if (NumBytes == 0) return;
238 // Add the size of R1 to NumBytes size for the store of R1 to the bottom
239 // of the stack and round the size to a multiple of the alignment.
240 unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment();
241 unsigned R1Size = getRegClass(PPC::R1)->getSize();
242 unsigned R31Size = getRegClass(PPC::R31)->getSize();
243 unsigned Size = (hasFP(MF)) ? R1Size + R31Size : R1Size;
244 NumBytes = (NumBytes+Size+Align-1)/Align*Align;
246 // Update frame info to pretend that this is part of the stack...
247 MFI->setStackSize(NumBytes);
249 // adjust stack pointer: r1 -= numbytes
250 if (NumBytes <= 32768) {
251 MI=BuildMI(PPC::STWU,3).addReg(PPC::R1).addSImm(-NumBytes).addReg(PPC::R1);
252 MBB.insert(MBBI, MI);
254 int NegNumbytes = -NumBytes;
255 MI = BuildMI(PPC::LIS, 1, PPC::R0).addSImm(NegNumbytes >> 16);
256 MBB.insert(MBBI, MI);
257 MI = BuildMI(PPC::ORI, 2, PPC::R0).addReg(PPC::R0)
258 .addImm(NegNumbytes & 0xFFFF);
259 MBB.insert(MBBI, MI);
260 MI = BuildMI(PPC::STWUX, 3).addReg(PPC::R1).addReg(PPC::R1).addReg(PPC::R0);
261 MBB.insert(MBBI, MI);
265 MI = BuildMI(PPC::STW, 3).addReg(PPC::R31).addSImm(R1Size).addReg(PPC::R1);
266 MBB.insert(MBBI, MI);
267 MI = BuildMI(PPC::OR, 2, PPC::R31).addReg(PPC::R1).addReg(PPC::R1);
268 MBB.insert(MBBI, MI);
272 void PPC32RegisterInfo::emitEpilogue(MachineFunction &MF,
273 MachineBasicBlock &MBB) const {
274 const MachineFrameInfo *MFI = MF.getFrameInfo();
275 MachineBasicBlock::iterator MBBI = prior(MBB.end());
277 assert(MBBI->getOpcode() == PPC::BLR &&
278 "Can only insert epilog into returning blocks");
280 // Get the number of bytes allocated from the FrameInfo...
281 unsigned NumBytes = MFI->getStackSize();
285 MI = BuildMI(PPC::OR, 2, PPC::R1).addReg(PPC::R31).addReg(PPC::R31);
286 MBB.insert(MBBI, MI);
287 MI = BuildMI(PPC::LWZ, 2, PPC::R31).addSImm(4).addReg(PPC::R31);
288 MBB.insert(MBBI, MI);
290 MI = BuildMI(PPC::LWZ, 2, PPC::R1).addSImm(0).addReg(PPC::R1);
291 MBB.insert(MBBI, MI);
295 #include "PPC32GenRegisterInfo.inc"
297 const TargetRegisterClass*
298 PPC32RegisterInfo::getRegClassForType(const Type* Ty) const {
299 switch (Ty->getTypeID()) {
300 default: assert(0 && "Invalid type to getClass!");
302 case Type::ULongTyID: assert(0 && "Long values can't fit in registers!");
304 case Type::SByteTyID:
305 case Type::UByteTyID:
306 case Type::ShortTyID:
307 case Type::UShortTyID:
310 case Type::PointerTyID: return &GPRCInstance;
312 case Type::FloatTyID:
313 case Type::DoubleTyID: return &FPRCInstance;