MipsCodeEmitter.cpp revision d04a8d4b33ff316ca4cf961e06c9e312eff8e64f
1//===-- Mips/MipsCodeEmitter.cpp - Convert Mips Code to Machine Code ------===// 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 pass that transforms the Mips machine instructions 11// into relocatable machine code. 12// 13//===---------------------------------------------------------------------===// 14 15#define DEBUG_TYPE "jit" 16#include "Mips.h" 17#include "MCTargetDesc/MipsBaseInfo.h" 18#include "MipsInstrInfo.h" 19#include "MipsRelocations.h" 20#include "MipsSubtarget.h" 21#include "MipsTargetMachine.h" 22#include "llvm/ADT/Statistic.h" 23#include "llvm/CodeGen/JITCodeEmitter.h" 24#include "llvm/CodeGen/MachineConstantPool.h" 25#include "llvm/CodeGen/MachineFunctionPass.h" 26#include "llvm/CodeGen/MachineInstr.h" 27#include "llvm/CodeGen/MachineJumpTableInfo.h" 28#include "llvm/CodeGen/MachineModuleInfo.h" 29#include "llvm/CodeGen/MachineOperand.h" 30#include "llvm/CodeGen/Passes.h" 31#include "llvm/Constants.h" 32#include "llvm/DerivedTypes.h" 33#include "llvm/PassManager.h" 34#include "llvm/Support/Debug.h" 35#include "llvm/Support/ErrorHandling.h" 36#include "llvm/Support/raw_ostream.h" 37#ifndef NDEBUG 38#include <iomanip> 39#endif 40 41using namespace llvm; 42 43STATISTIC(NumEmitted, "Number of machine instructions emitted"); 44 45namespace { 46 47class MipsCodeEmitter : public MachineFunctionPass { 48 MipsJITInfo *JTI; 49 const MipsInstrInfo *II; 50 const DataLayout *TD; 51 const MipsSubtarget *Subtarget; 52 TargetMachine &TM; 53 JITCodeEmitter &MCE; 54 const std::vector<MachineConstantPoolEntry> *MCPEs; 55 const std::vector<MachineJumpTableEntry> *MJTEs; 56 bool IsPIC; 57 58 void getAnalysisUsage(AnalysisUsage &AU) const { 59 AU.addRequired<MachineModuleInfo> (); 60 MachineFunctionPass::getAnalysisUsage(AU); 61 } 62 63 static char ID; 64 65 public: 66 MipsCodeEmitter(TargetMachine &tm, JITCodeEmitter &mce) : 67 MachineFunctionPass(ID), JTI(0), 68 II((const MipsInstrInfo *) tm.getInstrInfo()), 69 TD(tm.getDataLayout()), TM(tm), MCE(mce), MCPEs(0), MJTEs(0), 70 IsPIC(TM.getRelocationModel() == Reloc::PIC_) { 71 } 72 73 bool runOnMachineFunction(MachineFunction &MF); 74 75 virtual const char *getPassName() const { 76 return "Mips Machine Code Emitter"; 77 } 78 79 /// getBinaryCodeForInstr - This function, generated by the 80 /// CodeEmitterGenerator using TableGen, produces the binary encoding for 81 /// machine instructions. 82 uint64_t getBinaryCodeForInstr(const MachineInstr &MI) const; 83 84 void emitInstruction(const MachineInstr &MI); 85 86 private: 87 88 void emitWordLE(unsigned Word); 89 90 /// Routines that handle operands which add machine relocations which are 91 /// fixed up by the relocation stage. 92 void emitGlobalAddress(const GlobalValue *GV, unsigned Reloc, 93 bool MayNeedFarStub) const; 94 void emitExternalSymbolAddress(const char *ES, unsigned Reloc) const; 95 void emitConstPoolAddress(unsigned CPI, unsigned Reloc) const; 96 void emitJumpTableAddress(unsigned JTIndex, unsigned Reloc) const; 97 void emitMachineBasicBlock(MachineBasicBlock *BB, unsigned Reloc) const; 98 99 /// getMachineOpValue - Return binary encoding of operand. If the machine 100 /// operand requires relocation, record the relocation and return zero. 101 unsigned getMachineOpValue(const MachineInstr &MI, 102 const MachineOperand &MO) const; 103 104 unsigned getRelocation(const MachineInstr &MI, 105 const MachineOperand &MO) const; 106 107 unsigned getJumpTargetOpValue(const MachineInstr &MI, unsigned OpNo) const; 108 109 unsigned getBranchTargetOpValue(const MachineInstr &MI, 110 unsigned OpNo) const; 111 unsigned getMemEncoding(const MachineInstr &MI, unsigned OpNo) const; 112 unsigned getSizeExtEncoding(const MachineInstr &MI, unsigned OpNo) const; 113 unsigned getSizeInsEncoding(const MachineInstr &MI, unsigned OpNo) const; 114 115 int emitULW(const MachineInstr &MI); 116 int emitUSW(const MachineInstr &MI); 117 int emitULH(const MachineInstr &MI); 118 int emitULHu(const MachineInstr &MI); 119 int emitUSH(const MachineInstr &MI); 120 121 void emitGlobalAddressUnaligned(const GlobalValue *GV, unsigned Reloc, 122 int Offset) const; 123 }; 124} 125 126char MipsCodeEmitter::ID = 0; 127 128bool MipsCodeEmitter::runOnMachineFunction(MachineFunction &MF) { 129 JTI = ((MipsTargetMachine&) MF.getTarget()).getJITInfo(); 130 II = ((const MipsTargetMachine&) MF.getTarget()).getInstrInfo(); 131 TD = ((const MipsTargetMachine&) MF.getTarget()).getDataLayout(); 132 Subtarget = &TM.getSubtarget<MipsSubtarget> (); 133 MCPEs = &MF.getConstantPool()->getConstants(); 134 MJTEs = 0; 135 if (MF.getJumpTableInfo()) MJTEs = &MF.getJumpTableInfo()->getJumpTables(); 136 JTI->Initialize(MF, IsPIC); 137 MCE.setModuleInfo(&getAnalysis<MachineModuleInfo> ()); 138 139 do { 140 DEBUG(errs() << "JITTing function '" 141 << MF.getName() << "'\n"); 142 MCE.startFunction(MF); 143 144 for (MachineFunction::iterator MBB = MF.begin(), E = MF.end(); 145 MBB != E; ++MBB){ 146 MCE.StartMachineBasicBlock(MBB); 147 for (MachineBasicBlock::instr_iterator I = MBB->instr_begin(), 148 E = MBB->instr_end(); I != E; ++I) 149 emitInstruction(*I); 150 } 151 } while (MCE.finishFunction(MF)); 152 153 return false; 154} 155 156unsigned MipsCodeEmitter::getRelocation(const MachineInstr &MI, 157 const MachineOperand &MO) const { 158 // NOTE: This relocations are for static. 159 uint64_t TSFlags = MI.getDesc().TSFlags; 160 uint64_t Form = TSFlags & MipsII::FormMask; 161 if (Form == MipsII::FrmJ) 162 return Mips::reloc_mips_26; 163 if ((Form == MipsII::FrmI || Form == MipsII::FrmFI) 164 && MI.isBranch()) 165 return Mips::reloc_mips_pc16; 166 if (Form == MipsII::FrmI && MI.getOpcode() == Mips::LUi) 167 return Mips::reloc_mips_hi; 168 return Mips::reloc_mips_lo; 169} 170 171unsigned MipsCodeEmitter::getJumpTargetOpValue(const MachineInstr &MI, 172 unsigned OpNo) const { 173 MachineOperand MO = MI.getOperand(OpNo); 174 if (MO.isGlobal()) 175 emitGlobalAddress(MO.getGlobal(), getRelocation(MI, MO), true); 176 else if (MO.isSymbol()) 177 emitExternalSymbolAddress(MO.getSymbolName(), getRelocation(MI, MO)); 178 else if (MO.isMBB()) 179 emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO)); 180 else 181 llvm_unreachable("Unexpected jump target operand kind."); 182 return 0; 183} 184 185unsigned MipsCodeEmitter::getBranchTargetOpValue(const MachineInstr &MI, 186 unsigned OpNo) const { 187 MachineOperand MO = MI.getOperand(OpNo); 188 emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO)); 189 return 0; 190} 191 192unsigned MipsCodeEmitter::getMemEncoding(const MachineInstr &MI, 193 unsigned OpNo) const { 194 // Base register is encoded in bits 20-16, offset is encoded in bits 15-0. 195 assert(MI.getOperand(OpNo).isReg()); 196 unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo)) << 16; 197 return (getMachineOpValue(MI, MI.getOperand(OpNo+1)) & 0xFFFF) | RegBits; 198} 199 200unsigned MipsCodeEmitter::getSizeExtEncoding(const MachineInstr &MI, 201 unsigned OpNo) const { 202 // size is encoded as size-1. 203 return getMachineOpValue(MI, MI.getOperand(OpNo)) - 1; 204} 205 206unsigned MipsCodeEmitter::getSizeInsEncoding(const MachineInstr &MI, 207 unsigned OpNo) const { 208 // size is encoded as pos+size-1. 209 return getMachineOpValue(MI, MI.getOperand(OpNo-1)) + 210 getMachineOpValue(MI, MI.getOperand(OpNo)) - 1; 211} 212 213/// getMachineOpValue - Return binary encoding of operand. If the machine 214/// operand requires relocation, record the relocation and return zero. 215unsigned MipsCodeEmitter::getMachineOpValue(const MachineInstr &MI, 216 const MachineOperand &MO) const { 217 if (MO.isReg()) 218 return getMipsRegisterNumbering(MO.getReg()); 219 else if (MO.isImm()) 220 return static_cast<unsigned>(MO.getImm()); 221 else if (MO.isGlobal()) 222 emitGlobalAddress(MO.getGlobal(), getRelocation(MI, MO), true); 223 else if (MO.isSymbol()) 224 emitExternalSymbolAddress(MO.getSymbolName(), getRelocation(MI, MO)); 225 else if (MO.isCPI()) 226 emitConstPoolAddress(MO.getIndex(), getRelocation(MI, MO)); 227 else if (MO.isJTI()) 228 emitJumpTableAddress(MO.getIndex(), getRelocation(MI, MO)); 229 else if (MO.isMBB()) 230 emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO)); 231 else 232 llvm_unreachable("Unable to encode MachineOperand!"); 233 return 0; 234} 235 236void MipsCodeEmitter::emitGlobalAddress(const GlobalValue *GV, unsigned Reloc, 237 bool MayNeedFarStub) const { 238 MCE.addRelocation(MachineRelocation::getGV(MCE.getCurrentPCOffset(), Reloc, 239 const_cast<GlobalValue *>(GV), 0, 240 MayNeedFarStub)); 241} 242 243void MipsCodeEmitter::emitGlobalAddressUnaligned(const GlobalValue *GV, 244 unsigned Reloc, int Offset) const { 245 MCE.addRelocation(MachineRelocation::getGV(MCE.getCurrentPCOffset(), Reloc, 246 const_cast<GlobalValue *>(GV), 0, false)); 247 MCE.addRelocation(MachineRelocation::getGV(MCE.getCurrentPCOffset() + Offset, 248 Reloc, const_cast<GlobalValue *>(GV), 0, false)); 249} 250 251void MipsCodeEmitter:: 252emitExternalSymbolAddress(const char *ES, unsigned Reloc) const { 253 MCE.addRelocation(MachineRelocation::getExtSym(MCE.getCurrentPCOffset(), 254 Reloc, ES, 0, 0)); 255} 256 257void MipsCodeEmitter::emitConstPoolAddress(unsigned CPI, unsigned Reloc) const { 258 MCE.addRelocation(MachineRelocation::getConstPool(MCE.getCurrentPCOffset(), 259 Reloc, CPI, 0, false)); 260} 261 262void MipsCodeEmitter:: 263emitJumpTableAddress(unsigned JTIndex, unsigned Reloc) const { 264 MCE.addRelocation(MachineRelocation::getJumpTable(MCE.getCurrentPCOffset(), 265 Reloc, JTIndex, 0, false)); 266} 267 268void MipsCodeEmitter::emitMachineBasicBlock(MachineBasicBlock *BB, 269 unsigned Reloc) const { 270 MCE.addRelocation(MachineRelocation::getBB(MCE.getCurrentPCOffset(), 271 Reloc, BB)); 272} 273 274int MipsCodeEmitter::emitUSW(const MachineInstr &MI) { 275 unsigned src = getMachineOpValue(MI, MI.getOperand(0)); 276 unsigned base = getMachineOpValue(MI, MI.getOperand(1)); 277 unsigned offset = getMachineOpValue(MI, MI.getOperand(2)); 278 // swr src, offset(base) 279 // swl src, offset+3(base) 280 MCE.emitWordLE( 281 (0x2e << 26) | (base << 21) | (src << 16) | (offset & 0xffff)); 282 MCE.emitWordLE( 283 (0x2a << 26) | (base << 21) | (src << 16) | ((offset+3) & 0xffff)); 284 return 2; 285} 286 287int MipsCodeEmitter::emitULW(const MachineInstr &MI) { 288 unsigned dst = getMachineOpValue(MI, MI.getOperand(0)); 289 unsigned base = getMachineOpValue(MI, MI.getOperand(1)); 290 unsigned offset = getMachineOpValue(MI, MI.getOperand(2)); 291 unsigned at = 1; 292 if (dst != base) { 293 // lwr dst, offset(base) 294 // lwl dst, offset+3(base) 295 MCE.emitWordLE( 296 (0x26 << 26) | (base << 21) | (dst << 16) | (offset & 0xffff)); 297 MCE.emitWordLE( 298 (0x22 << 26) | (base << 21) | (dst << 16) | ((offset+3) & 0xffff)); 299 return 2; 300 } else { 301 // lwr at, offset(base) 302 // lwl at, offset+3(base) 303 // addu dst, at, $zero 304 MCE.emitWordLE( 305 (0x26 << 26) | (base << 21) | (at << 16) | (offset & 0xffff)); 306 MCE.emitWordLE( 307 (0x22 << 26) | (base << 21) | (at << 16) | ((offset+3) & 0xffff)); 308 MCE.emitWordLE( 309 (0x0 << 26) | (at << 21) | (0x0 << 16) | (dst << 11) | (0x0 << 6) | 0x21); 310 return 3; 311 } 312} 313 314int MipsCodeEmitter::emitUSH(const MachineInstr &MI) { 315 unsigned src = getMachineOpValue(MI, MI.getOperand(0)); 316 unsigned base = getMachineOpValue(MI, MI.getOperand(1)); 317 unsigned offset = getMachineOpValue(MI, MI.getOperand(2)); 318 unsigned at = 1; 319 // sb src, offset(base) 320 // srl at,src,8 321 // sb at, offset+1(base) 322 MCE.emitWordLE( 323 (0x28 << 26) | (base << 21) | (src << 16) | (offset & 0xffff)); 324 MCE.emitWordLE( 325 (0x0 << 26) | (0x0 << 21) | (src << 16) | (at << 11) | (0x8 << 6) | 0x2); 326 MCE.emitWordLE( 327 (0x28 << 26) | (base << 21) | (at << 16) | ((offset+1) & 0xffff)); 328 return 3; 329} 330 331int MipsCodeEmitter::emitULH(const MachineInstr &MI) { 332 unsigned dst = getMachineOpValue(MI, MI.getOperand(0)); 333 unsigned base = getMachineOpValue(MI, MI.getOperand(1)); 334 unsigned offset = getMachineOpValue(MI, MI.getOperand(2)); 335 unsigned at = 1; 336 // lbu at, offset(base) 337 // lb dst, offset+1(base) 338 // sll dst,dst,8 339 // or dst,dst,at 340 MCE.emitWordLE( 341 (0x24 << 26) | (base << 21) | (at << 16) | (offset & 0xffff)); 342 MCE.emitWordLE( 343 (0x20 << 26) | (base << 21) | (dst << 16) | ((offset+1) & 0xffff)); 344 MCE.emitWordLE( 345 (0x0 << 26) | (0x0 << 21) | (dst << 16) | (dst << 11) | (0x8 << 6) | 0x0); 346 MCE.emitWordLE( 347 (0x0 << 26) | (dst << 21) | (at << 16) | (dst << 11) | (0x0 << 6) | 0x25); 348 return 4; 349} 350 351int MipsCodeEmitter::emitULHu(const MachineInstr &MI) { 352 unsigned dst = getMachineOpValue(MI, MI.getOperand(0)); 353 unsigned base = getMachineOpValue(MI, MI.getOperand(1)); 354 unsigned offset = getMachineOpValue(MI, MI.getOperand(2)); 355 unsigned at = 1; 356 // lbu at, offset(base) 357 // lbu dst, offset+1(base) 358 // sll dst,dst,8 359 // or dst,dst,at 360 MCE.emitWordLE( 361 (0x24 << 26) | (base << 21) | (at << 16) | (offset & 0xffff)); 362 MCE.emitWordLE( 363 (0x24 << 26) | (base << 21) | (dst << 16) | ((offset+1) & 0xffff)); 364 MCE.emitWordLE( 365 (0x0 << 26) | (0x0 << 21) | (dst << 16) | (dst << 11) | (0x8 << 6) | 0x0); 366 MCE.emitWordLE( 367 (0x0 << 26) | (dst << 21) | (at << 16) | (dst << 11) | (0x0 << 6) | 0x25); 368 return 4; 369} 370 371void MipsCodeEmitter::emitInstruction(const MachineInstr &MI) { 372 DEBUG(errs() << "JIT: " << (void*)MCE.getCurrentPCValue() << ":\t" << MI); 373 374 MCE.processDebugLoc(MI.getDebugLoc(), true); 375 376 // Skip pseudo instructions. 377 if ((MI.getDesc().TSFlags & MipsII::FormMask) == MipsII::Pseudo) 378 return; 379 380 emitWordLE(getBinaryCodeForInstr(MI)); 381 ++NumEmitted; // Keep track of the # of mi's emitted 382 383 MCE.processDebugLoc(MI.getDebugLoc(), false); 384} 385 386void MipsCodeEmitter::emitWordLE(unsigned Word) { 387 DEBUG(errs() << " 0x"; 388 errs().write_hex(Word) << "\n"); 389 MCE.emitWordLE(Word); 390} 391 392/// createMipsJITCodeEmitterPass - Return a pass that emits the collected Mips 393/// code to the specified MCE object. 394FunctionPass *llvm::createMipsJITCodeEmitterPass(MipsTargetMachine &TM, 395 JITCodeEmitter &JCE) { 396 return new MipsCodeEmitter(TM, JCE); 397} 398 399#include "MipsGenCodeEmitter.inc" 400