1 //===-- HexagonRegisterInfo.cpp - Hexagon Register Information ------------===//
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 Hexagon implementation of the TargetRegisterInfo
13 //===----------------------------------------------------------------------===//
15 #include "HexagonRegisterInfo.h"
17 #include "HexagonMachineFunctionInfo.h"
18 #include "HexagonSubtarget.h"
19 #include "HexagonTargetMachine.h"
20 #include "llvm/ADT/BitVector.h"
21 #include "llvm/ADT/STLExtras.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineFunctionPass.h"
25 #include "llvm/CodeGen/MachineInstrBuilder.h"
26 #include "llvm/CodeGen/MachineRegisterInfo.h"
27 #include "llvm/CodeGen/RegisterScavenging.h"
28 #include "llvm/IR/Function.h"
29 #include "llvm/IR/Type.h"
30 #include "llvm/MC/MachineLocation.h"
31 #include "llvm/Support/CommandLine.h"
32 #include "llvm/Support/ErrorHandling.h"
33 #include "llvm/Target/TargetInstrInfo.h"
34 #include "llvm/Target/TargetMachine.h"
35 #include "llvm/Target/TargetOptions.h"
40 HexagonRegisterInfo::HexagonRegisterInfo(HexagonSubtarget &st,
41 const HexagonInstrInfo &tii)
42 : HexagonGenRegisterInfo(Hexagon::R31),
47 const uint16_t* HexagonRegisterInfo::getCalleeSavedRegs(const MachineFunction
50 static const uint16_t CalleeSavedRegsV2[] = {
51 Hexagon::R24, Hexagon::R25, Hexagon::R26, Hexagon::R27, 0
53 static const uint16_t CalleeSavedRegsV3[] = {
54 Hexagon::R16, Hexagon::R17, Hexagon::R18, Hexagon::R19,
55 Hexagon::R20, Hexagon::R21, Hexagon::R22, Hexagon::R23,
56 Hexagon::R24, Hexagon::R25, Hexagon::R26, Hexagon::R27, 0
59 switch(Subtarget.getHexagonArchVersion()) {
60 case HexagonSubtarget::V1:
62 case HexagonSubtarget::V2:
63 return CalleeSavedRegsV2;
64 case HexagonSubtarget::V3:
65 case HexagonSubtarget::V4:
66 case HexagonSubtarget::V5:
67 return CalleeSavedRegsV3;
69 llvm_unreachable("Callee saved registers requested for unknown architecture "
73 BitVector HexagonRegisterInfo::getReservedRegs(const MachineFunction &MF)
75 BitVector Reserved(getNumRegs());
76 Reserved.set(HEXAGON_RESERVED_REG_1);
77 Reserved.set(HEXAGON_RESERVED_REG_2);
78 Reserved.set(Hexagon::R29);
79 Reserved.set(Hexagon::R30);
80 Reserved.set(Hexagon::R31);
81 Reserved.set(Hexagon::D14);
82 Reserved.set(Hexagon::D15);
83 Reserved.set(Hexagon::LC0);
84 Reserved.set(Hexagon::LC1);
85 Reserved.set(Hexagon::SA0);
86 Reserved.set(Hexagon::SA1);
91 const TargetRegisterClass* const*
92 HexagonRegisterInfo::getCalleeSavedRegClasses(const MachineFunction *MF) const {
93 static const TargetRegisterClass * const CalleeSavedRegClassesV2[] = {
94 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
95 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
97 static const TargetRegisterClass * const CalleeSavedRegClassesV3[] = {
98 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
99 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
100 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
101 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
102 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
103 &Hexagon::IntRegsRegClass, &Hexagon::IntRegsRegClass,
106 switch(Subtarget.getHexagonArchVersion()) {
107 case HexagonSubtarget::V1:
109 case HexagonSubtarget::V2:
110 return CalleeSavedRegClassesV2;
111 case HexagonSubtarget::V3:
112 case HexagonSubtarget::V4:
113 case HexagonSubtarget::V5:
114 return CalleeSavedRegClassesV3;
116 llvm_unreachable("Callee saved register classes requested for unknown "
117 "architecture version");
120 void HexagonRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
121 int SPAdj, unsigned FIOperandNum,
122 RegScavenger *RS) const {
124 // Hexagon_TODO: Do we need to enforce this for Hexagon?
125 assert(SPAdj == 0 && "Unexpected");
127 MachineInstr &MI = *II;
128 int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
130 // Addressable stack objects are accessed using neg. offsets from %fp.
131 MachineFunction &MF = *MI.getParent()->getParent();
132 int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
133 MachineFrameInfo &MFI = *MF.getFrameInfo();
135 unsigned FrameReg = getFrameRegister(MF);
136 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
137 if (!TFI->hasFP(MF)) {
138 // We will not reserve space on the stack for the lr and fp registers.
139 Offset -= 2 * Hexagon_WordSize;
142 const unsigned FrameSize = MFI.getStackSize();
144 if (!MFI.hasVarSizedObjects() &&
145 TII.isValidOffset(MI.getOpcode(), (FrameSize+Offset)) &&
146 !TII.isSpillPredRegOp(&MI)) {
147 // Replace frame index with a stack pointer reference.
148 MI.getOperand(FIOperandNum).ChangeToRegister(getStackRegister(), false,
150 MI.getOperand(FIOperandNum + 1).ChangeToImmediate(FrameSize+Offset);
152 // Replace frame index with a frame pointer reference.
153 if (!TII.isValidOffset(MI.getOpcode(), Offset)) {
155 // If the offset overflows, then correct it.
157 // For loads, we do not need a reserved register
158 // r0 = memw(r30 + #10000) to:
160 // r0 = add(r30, #10000)
162 if ( (MI.getOpcode() == Hexagon::LDriw) ||
163 (MI.getOpcode() == Hexagon::LDrid) ||
164 (MI.getOpcode() == Hexagon::LDrih) ||
165 (MI.getOpcode() == Hexagon::LDriuh) ||
166 (MI.getOpcode() == Hexagon::LDrib) ||
167 (MI.getOpcode() == Hexagon::LDriub) ||
168 (MI.getOpcode() == Hexagon::LDriw_f) ||
169 (MI.getOpcode() == Hexagon::LDrid_f)) {
170 unsigned dstReg = (MI.getOpcode() == Hexagon::LDrid) ?
171 getSubReg(MI.getOperand(0).getReg(), Hexagon::subreg_loreg) :
172 MI.getOperand(0).getReg();
174 // Check if offset can fit in addi.
175 if (!TII.isValidOffset(Hexagon::ADD_ri, Offset)) {
176 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
177 TII.get(Hexagon::CONST32_Int_Real), dstReg).addImm(Offset);
178 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
179 TII.get(Hexagon::ADD_rr),
180 dstReg).addReg(FrameReg).addReg(dstReg);
182 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
183 TII.get(Hexagon::ADD_ri),
184 dstReg).addReg(FrameReg).addImm(Offset);
187 MI.getOperand(FIOperandNum).ChangeToRegister(dstReg, false, false,true);
188 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
189 } else if ((MI.getOpcode() == Hexagon::STriw_indexed) ||
190 (MI.getOpcode() == Hexagon::STriw) ||
191 (MI.getOpcode() == Hexagon::STrid) ||
192 (MI.getOpcode() == Hexagon::STrih) ||
193 (MI.getOpcode() == Hexagon::STrib) ||
194 (MI.getOpcode() == Hexagon::STrid_f) ||
195 (MI.getOpcode() == Hexagon::STriw_f)) {
196 // For stores, we need a reserved register. Change
197 // memw(r30 + #10000) = r0 to:
199 // rs = add(r30, #10000);
201 unsigned resReg = HEXAGON_RESERVED_REG_1;
203 // Check if offset can fit in addi.
204 if (!TII.isValidOffset(Hexagon::ADD_ri, Offset)) {
205 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
206 TII.get(Hexagon::CONST32_Int_Real), resReg).addImm(Offset);
207 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
208 TII.get(Hexagon::ADD_rr),
209 resReg).addReg(FrameReg).addReg(resReg);
211 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
212 TII.get(Hexagon::ADD_ri),
213 resReg).addReg(FrameReg).addImm(Offset);
215 MI.getOperand(FIOperandNum).ChangeToRegister(resReg, false, false,true);
216 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
217 } else if (TII.isMemOp(&MI)) {
218 unsigned resReg = HEXAGON_RESERVED_REG_1;
219 if (!MFI.hasVarSizedObjects() &&
220 TII.isValidOffset(MI.getOpcode(), (FrameSize+Offset))) {
221 MI.getOperand(FIOperandNum).ChangeToRegister(getStackRegister(),
223 MI.getOperand(FIOperandNum+1).ChangeToImmediate(FrameSize+Offset);
224 } else if (!TII.isValidOffset(Hexagon::ADD_ri, Offset)) {
225 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
226 TII.get(Hexagon::CONST32_Int_Real), resReg).addImm(Offset);
227 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
228 TII.get(Hexagon::ADD_rr),
229 resReg).addReg(FrameReg).addReg(resReg);
230 MI.getOperand(FIOperandNum).ChangeToRegister(resReg, false, false,
232 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
234 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
235 TII.get(Hexagon::ADD_ri),
236 resReg).addReg(FrameReg).addImm(Offset);
237 MI.getOperand(FIOperandNum).ChangeToRegister(resReg, false, false,
239 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
242 unsigned dstReg = MI.getOperand(0).getReg();
243 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
244 TII.get(Hexagon::CONST32_Int_Real), dstReg).addImm(Offset);
245 BuildMI(*MI.getParent(), II, MI.getDebugLoc(),
246 TII.get(Hexagon::ADD_rr),
247 dstReg).addReg(FrameReg).addReg(dstReg);
248 // Can we delete MI??? r2 = add (r2, #0).
249 MI.getOperand(FIOperandNum).ChangeToRegister(dstReg, false, false,true);
250 MI.getOperand(FIOperandNum+1).ChangeToImmediate(0);
253 // If the offset is small enough to fit in the immediate field, directly
255 MI.getOperand(FIOperandNum).ChangeToRegister(FrameReg, false);
256 MI.getOperand(FIOperandNum+1).ChangeToImmediate(Offset);
262 unsigned HexagonRegisterInfo::getRARegister() const {
266 unsigned HexagonRegisterInfo::getFrameRegister(const MachineFunction
268 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
269 if (TFI->hasFP(MF)) {
276 unsigned HexagonRegisterInfo::getFrameRegister() const {
280 unsigned HexagonRegisterInfo::getStackRegister() const {
284 void HexagonRegisterInfo::getInitialFrameState(std::vector<MachineMove>
287 // VirtualFP = (R30 + #0).
288 unsigned FPReg = getFrameRegister();
289 MachineLocation Dst(MachineLocation::VirtualFP);
290 MachineLocation Src(FPReg, 0);
291 Moves.push_back(MachineMove(0, Dst, Src));
294 // Get the weight in units of pressure for this register class.
295 const RegClassWeight &
296 HexagonRegisterInfo::getRegClassWeight(const TargetRegisterClass *RC) const {
297 // Each TargetRegisterClass has a per register weight, and weight
298 // limit which must be less than the limits of its pressure sets.
299 static const RegClassWeight RCWeightTable[] = {
303 {2, 16}, // DoubleRegs
305 return RCWeightTable[RC->getID()];
308 /// Get the number of dimensions of register pressure.
309 unsigned HexagonRegisterInfo::getNumRegPressureSets() const {
313 /// Get the name of this register unit pressure set.
314 const char *HexagonRegisterInfo::getRegPressureSetName(unsigned Idx) const {
315 static const char *const RegPressureSetName[] = {
321 assert((Idx < 4) && "Index out of bounds");
322 return RegPressureSetName[Idx];
325 /// Get the register unit pressure limit for this dimension.
326 /// This limit must be adjusted dynamically for reserved registers.
327 unsigned HexagonRegisterInfo::getRegPressureSetLimit(unsigned Idx) const {
328 static const int RegPressureLimit [] = { 16, 4, 2, 8 };
329 assert((Idx < 4) && "Index out of bounds");
330 return RegPressureLimit[Idx];
334 HexagonRegisterInfo::getRegClassPressureSets(const TargetRegisterClass *RC)
336 static const int RCSetsTable[] = {
342 static const unsigned RCSetStartTable[] = { 0, 2, 4, 6, 0 };
343 unsigned SetListStart = RCSetStartTable[RC->getID()];
344 return &RCSetsTable[SetListStart];
346 unsigned HexagonRegisterInfo::getEHExceptionRegister() const {
347 llvm_unreachable("What is the exception register");
350 unsigned HexagonRegisterInfo::getEHHandlerRegister() const {
351 llvm_unreachable("What is the exception handler register");
354 #define GET_REGINFO_TARGET_DESC
355 #include "HexagonGenRegisterInfo.inc"