SparcAsmPrinter.cpp revision 6fdd9e1f3566ec9cc7a66c0ca2cd742057ac95f0
1//===-- SparcV8AsmPrinter.cpp - SparcV8 LLVM assembly writer --------------===// 2// 3// The LLVM Compiler Infrastructure 4// 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. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file contains a printer that converts from our internal representation 11// of machine-dependent LLVM code to GAS-format Sparc V8 assembly language. 12// 13//===----------------------------------------------------------------------===// 14 15#include "SparcV8.h" 16#include "SparcV8InstrInfo.h" 17#include "llvm/Constants.h" 18#include "llvm/DerivedTypes.h" 19#include "llvm/Module.h" 20#include "llvm/Assembly/Writer.h" 21#include "llvm/CodeGen/MachineFunctionPass.h" 22#include "llvm/CodeGen/MachineConstantPool.h" 23#include "llvm/CodeGen/MachineInstr.h" 24#include "llvm/Target/TargetMachine.h" 25#include "llvm/Support/Mangler.h" 26#include "llvm/ADT/Statistic.h" 27#include "llvm/ADT/StringExtras.h" 28#include "llvm/Support/CommandLine.h" 29#include <cctype> 30using namespace llvm; 31 32namespace { 33 Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed"); 34 35 struct V8Printer : public MachineFunctionPass { 36 /// Output stream on which we're printing assembly code. 37 /// 38 std::ostream &O; 39 40 /// Target machine description which we query for reg. names, data 41 /// layout, etc. 42 /// 43 TargetMachine &TM; 44 45 /// Name-mangler for global names. 46 /// 47 Mangler *Mang; 48 49 V8Printer(std::ostream &o, TargetMachine &tm) : O(o), TM(tm) { } 50 51 /// We name each basic block in a Function with a unique number, so 52 /// that we can consistently refer to them later. This is cleared 53 /// at the beginning of each call to runOnMachineFunction(). 54 /// 55 typedef std::map<const Value *, unsigned> ValueMapTy; 56 ValueMapTy NumberForBB; 57 58 /// Cache of mangled name for current function. This is 59 /// recalculated at the beginning of each call to 60 /// runOnMachineFunction(). 61 /// 62 std::string CurrentFnName; 63 64 virtual const char *getPassName() const { 65 return "SparcV8 Assembly Printer"; 66 } 67 68 void emitConstantValueOnly(const Constant *CV); 69 void emitGlobalConstant(const Constant *CV); 70 void printConstantPool(MachineConstantPool *MCP); 71 void printOperand(const MachineInstr *MI, int opNum); 72 void printBaseOffsetPair (const MachineInstr *MI, int i, bool brackets=true); 73 void printMachineInstruction(const MachineInstr *MI); 74 bool runOnMachineFunction(MachineFunction &F); 75 bool doInitialization(Module &M); 76 bool doFinalization(Module &M); 77 }; 78} // end of anonymous namespace 79 80/// createSparcV8CodePrinterPass - Returns a pass that prints the SparcV8 81/// assembly code for a MachineFunction to the given output stream, 82/// using the given target machine description. This should work 83/// regardless of whether the function is in SSA form. 84/// 85FunctionPass *llvm::createSparcV8CodePrinterPass (std::ostream &o, 86 TargetMachine &tm) { 87 return new V8Printer(o, tm); 88} 89 90/// toOctal - Convert the low order bits of X into an octal digit. 91/// 92static inline char toOctal(int X) { 93 return (X&7)+'0'; 94} 95 96/// getAsCString - Return the specified array as a C compatible 97/// string, only if the predicate isStringCompatible is true. 98/// 99static void printAsCString(std::ostream &O, const ConstantArray *CVA) { 100 assert(CVA->isString() && "Array is not string compatible!"); 101 102 O << "\""; 103 for (unsigned i = 0; i != CVA->getNumOperands(); ++i) { 104 unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue(); 105 106 if (C == '"') { 107 O << "\\\""; 108 } else if (C == '\\') { 109 O << "\\\\"; 110 } else if (isprint(C)) { 111 O << C; 112 } else { 113 switch(C) { 114 case '\b': O << "\\b"; break; 115 case '\f': O << "\\f"; break; 116 case '\n': O << "\\n"; break; 117 case '\r': O << "\\r"; break; 118 case '\t': O << "\\t"; break; 119 default: 120 O << '\\'; 121 O << toOctal(C >> 6); 122 O << toOctal(C >> 3); 123 O << toOctal(C >> 0); 124 break; 125 } 126 } 127 } 128 O << "\""; 129} 130 131// Print out the specified constant, without a storage class. Only the 132// constants valid in constant expressions can occur here. 133void V8Printer::emitConstantValueOnly(const Constant *CV) { 134 if (CV->isNullValue()) 135 O << "0"; 136 else if (const ConstantBool *CB = dyn_cast<ConstantBool>(CV)) { 137 assert(CB == ConstantBool::True); 138 O << "1"; 139 } else if (const ConstantSInt *CI = dyn_cast<ConstantSInt>(CV)) 140 if (((CI->getValue() << 32) >> 32) == CI->getValue()) 141 O << CI->getValue(); 142 else 143 O << (unsigned long long)CI->getValue(); 144 else if (const ConstantUInt *CI = dyn_cast<ConstantUInt>(CV)) 145 O << CI->getValue(); 146 else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) 147 // This is a constant address for a global variable or function. Use the 148 // name of the variable or function as the address value. 149 O << Mang->getValueName(GV); 150 else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) { 151 const TargetData &TD = TM.getTargetData(); 152 switch(CE->getOpcode()) { 153 case Instruction::GetElementPtr: { 154 // generate a symbolic expression for the byte address 155 const Constant *ptrVal = CE->getOperand(0); 156 std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end()); 157 if (unsigned Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) { 158 O << "("; 159 emitConstantValueOnly(ptrVal); 160 O << ") + " << Offset; 161 } else { 162 emitConstantValueOnly(ptrVal); 163 } 164 break; 165 } 166 case Instruction::Cast: { 167 // Support only non-converting or widening casts for now, that is, ones 168 // that do not involve a change in value. This assertion is really gross, 169 // and may not even be a complete check. 170 Constant *Op = CE->getOperand(0); 171 const Type *OpTy = Op->getType(), *Ty = CE->getType(); 172 173 // Pointers on ILP32 machines can be losslessly converted back and 174 // forth into 32-bit or wider integers, regardless of signedness. 175 assert(((isa<PointerType>(OpTy) 176 && (Ty == Type::LongTy || Ty == Type::ULongTy 177 || Ty == Type::IntTy || Ty == Type::UIntTy)) 178 || (isa<PointerType>(Ty) 179 && (OpTy == Type::LongTy || OpTy == Type::ULongTy 180 || OpTy == Type::IntTy || OpTy == Type::UIntTy)) 181 || (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy)) 182 && OpTy->isLosslesslyConvertibleTo(Ty)))) 183 && "FIXME: Don't yet support this kind of constant cast expr"); 184 O << "("; 185 emitConstantValueOnly(Op); 186 O << ")"; 187 break; 188 } 189 case Instruction::Add: 190 O << "("; 191 emitConstantValueOnly(CE->getOperand(0)); 192 O << ") + ("; 193 emitConstantValueOnly(CE->getOperand(1)); 194 O << ")"; 195 break; 196 default: 197 assert(0 && "Unsupported operator!"); 198 } 199 } else { 200 assert(0 && "Unknown constant value!"); 201 } 202} 203 204// Print a constant value or values, with the appropriate storage class as a 205// prefix. 206void V8Printer::emitGlobalConstant(const Constant *CV) { 207 const TargetData &TD = TM.getTargetData(); 208 209 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) { 210 if (CVA->isString()) { 211 O << "\t.ascii\t"; 212 printAsCString(O, CVA); 213 O << "\n"; 214 } else { // Not a string. Print the values in successive locations 215 for (unsigned i = 0, e = CVA->getNumOperands(); i != e; i++) 216 emitGlobalConstant(CVA->getOperand(i)); 217 } 218 return; 219 } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) { 220 // Print the fields in successive locations. Pad to align if needed! 221 const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType()); 222 unsigned sizeSoFar = 0; 223 for (unsigned i = 0, e = CVS->getNumOperands(); i != e; i++) { 224 const Constant* field = CVS->getOperand(i); 225 226 // Check if padding is needed and insert one or more 0s. 227 unsigned fieldSize = TD.getTypeSize(field->getType()); 228 unsigned padSize = ((i == e-1? cvsLayout->StructSize 229 : cvsLayout->MemberOffsets[i+1]) 230 - cvsLayout->MemberOffsets[i]) - fieldSize; 231 sizeSoFar += fieldSize + padSize; 232 233 // Now print the actual field value 234 emitGlobalConstant(field); 235 236 // Insert the field padding unless it's zero bytes... 237 if (padSize) 238 O << "\t.skip\t " << padSize << "\n"; 239 } 240 assert(sizeSoFar == cvsLayout->StructSize && 241 "Layout of constant struct may be incorrect!"); 242 return; 243 } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) { 244 // FP Constants are printed as integer constants to avoid losing 245 // precision... 246 double Val = CFP->getValue(); 247 switch (CFP->getType()->getTypeID()) { 248 default: assert(0 && "Unknown floating point type!"); 249 case Type::FloatTyID: { 250 union FU { // Abide by C TBAA rules 251 float FVal; 252 unsigned UVal; 253 } U; 254 U.FVal = Val; 255 O << ".long\t" << U.UVal << "\t! float " << Val << "\n"; 256 return; 257 } 258 case Type::DoubleTyID: { 259 union DU { // Abide by C TBAA rules 260 double FVal; 261 uint64_t UVal; 262 } U; 263 U.FVal = Val; 264 O << ".word\t0x" << std::hex << (U.UVal >> 32) << std::dec << "\t! double " << Val << "\n"; 265 O << ".word\t0x" << std::hex << (U.UVal & 0xffffffffUL) << std::dec << "\t! double " << Val << "\n"; 266 return; 267 } 268 } 269 } 270 271 const Type *type = CV->getType(); 272 O << "\t"; 273 switch (type->getTypeID()) { 274 case Type::BoolTyID: case Type::UByteTyID: case Type::SByteTyID: 275 O << ".byte"; 276 break; 277 case Type::UShortTyID: case Type::ShortTyID: 278 O << ".word"; 279 break; 280 case Type::FloatTyID: case Type::PointerTyID: 281 case Type::UIntTyID: case Type::IntTyID: 282 O << ".long"; 283 break; 284 case Type::DoubleTyID: 285 case Type::ULongTyID: case Type::LongTyID: 286 O << ".quad"; 287 break; 288 default: 289 assert (0 && "Can't handle printing this type of thing"); 290 break; 291 } 292 O << "\t"; 293 emitConstantValueOnly(CV); 294 O << "\n"; 295} 296 297/// printConstantPool - Print to the current output stream assembly 298/// representations of the constants in the constant pool MCP. This is 299/// used to print out constants which have been "spilled to memory" by 300/// the code generator. 301/// 302void V8Printer::printConstantPool(MachineConstantPool *MCP) { 303 const std::vector<Constant*> &CP = MCP->getConstants(); 304 const TargetData &TD = TM.getTargetData(); 305 306 if (CP.empty()) return; 307 308 for (unsigned i = 0, e = CP.size(); i != e; ++i) { 309 O << "\t.section \".rodata\"\n"; 310 O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType()) 311 << "\n"; 312 O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t!" 313 << *CP[i] << "\n"; 314 emitGlobalConstant(CP[i]); 315 } 316} 317 318/// runOnMachineFunction - This uses the printMachineInstruction() 319/// method to print assembly for each instruction. 320/// 321bool V8Printer::runOnMachineFunction(MachineFunction &MF) { 322 // BBNumber is used here so that a given Printer will never give two 323 // BBs the same name. (If you have a better way, please let me know!) 324 static unsigned BBNumber = 0; 325 326 O << "\n\n"; 327 // What's my mangled name? 328 CurrentFnName = Mang->getValueName(MF.getFunction()); 329 330 // Print out constants referenced by the function 331 printConstantPool(MF.getConstantPool()); 332 333 // Print out labels for the function. 334 O << "\t.text\n"; 335 O << "\t.align 16\n"; 336 O << "\t.globl\t" << CurrentFnName << "\n"; 337 O << "\t.type\t" << CurrentFnName << ", #function\n"; 338 O << CurrentFnName << ":\n"; 339 340 // Number each basic block so that we can consistently refer to them 341 // in PC-relative references. 342 NumberForBB.clear(); 343 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end(); 344 I != E; ++I) { 345 NumberForBB[I->getBasicBlock()] = BBNumber++; 346 } 347 348 // Print out code for the function. 349 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end(); 350 I != E; ++I) { 351 // Print a label for the basic block. 352 O << ".LBB" << Mang->getValueName(MF.getFunction ()) 353 << "_" << I->getNumber () << ":\t! " 354 << I->getBasicBlock ()->getName () << "\n"; 355 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end(); 356 II != E; ++II) { 357 // Print the assembly for the instruction. 358 O << "\t"; 359 printMachineInstruction(II); 360 } 361 } 362 363 // We didn't modify anything. 364 return false; 365} 366 367void V8Printer::printOperand(const MachineInstr *MI, int opNum) { 368 const MachineOperand &MO = MI->getOperand (opNum); 369 const MRegisterInfo &RI = *TM.getRegisterInfo(); 370 bool CloseParen = false; 371 if (MI->getOpcode() == V8::SETHIi && !MO.isRegister() && !MO.isImmediate()) { 372 O << "%hi("; 373 CloseParen = true; 374 } else if (MI->getOpcode() ==V8::ORri &&!MO.isRegister() &&!MO.isImmediate()) 375 { 376 O << "%lo("; 377 CloseParen = true; 378 } 379 switch (MO.getType()) { 380 case MachineOperand::MO_VirtualRegister: 381 if (Value *V = MO.getVRegValueOrNull()) { 382 O << "<" << V->getName() << ">"; 383 break; 384 } 385 // FALLTHROUGH 386 case MachineOperand::MO_MachineRegister: 387 if (MRegisterInfo::isPhysicalRegister(MO.getReg())) 388 O << "%" << LowercaseString (RI.get(MO.getReg()).Name); 389 else 390 O << "%reg" << MO.getReg(); 391 break; 392 393 case MachineOperand::MO_SignExtendedImmed: 394 case MachineOperand::MO_UnextendedImmed: 395 O << (int)MO.getImmedValue(); 396 break; 397 case MachineOperand::MO_MachineBasicBlock: { 398 MachineBasicBlock *MBBOp = MO.getMachineBasicBlock(); 399 O << ".LBB" << Mang->getValueName(MBBOp->getParent()->getFunction()) 400 << "_" << MBBOp->getNumber () << "\t! " 401 << MBBOp->getBasicBlock ()->getName (); 402 return; 403 } 404 case MachineOperand::MO_PCRelativeDisp: 405 std::cerr << "Shouldn't use addPCDisp() when building SparcV8 MachineInstrs"; 406 abort (); 407 return; 408 case MachineOperand::MO_GlobalAddress: 409 O << Mang->getValueName(MO.getGlobal()); 410 break; 411 case MachineOperand::MO_ExternalSymbol: 412 O << MO.getSymbolName(); 413 break; 414 case MachineOperand::MO_ConstantPoolIndex: 415 O << ".CPI" << CurrentFnName << "_" << MO.getConstantPoolIndex(); 416 break; 417 default: 418 O << "<unknown operand type>"; abort (); break; 419 } 420 if (CloseParen) O << ")"; 421} 422 423static bool isLoadInstruction (const MachineInstr *MI) { 424 switch (MI->getOpcode ()) { 425 case V8::LDSB: 426 case V8::LDSH: 427 case V8::LDUB: 428 case V8::LDUH: 429 case V8::LD: 430 case V8::LDD: 431 case V8::LDFrr: 432 case V8::LDFri: 433 case V8::LDDFrr: 434 case V8::LDDFri: 435 return true; 436 default: 437 return false; 438 } 439} 440 441static bool isStoreInstruction (const MachineInstr *MI) { 442 switch (MI->getOpcode ()) { 443 case V8::STB: 444 case V8::STH: 445 case V8::ST: 446 case V8::STD: 447 case V8::STFrr: 448 case V8::STFri: 449 case V8::STDFrr: 450 case V8::STDFri: 451 return true; 452 default: 453 return false; 454 } 455} 456 457static bool isPseudoInstruction (const MachineInstr *MI) { 458 switch (MI->getOpcode ()) { 459 case V8::PHI: 460 case V8::ADJCALLSTACKUP: 461 case V8::ADJCALLSTACKDOWN: 462 case V8::IMPLICIT_USE: 463 case V8::IMPLICIT_DEF: 464 return true; 465 default: 466 return false; 467 } 468} 469 470/// printBaseOffsetPair - Print two consecutive operands of MI, starting at #i, 471/// which form a base + offset pair (which may have brackets around it, if 472/// brackets is true, or may be in the form base - constant, if offset is a 473/// negative constant). 474/// 475void V8Printer::printBaseOffsetPair (const MachineInstr *MI, int i, 476 bool brackets) { 477 if (brackets) O << "["; 478 printOperand (MI, i); 479 if (MI->getOperand (i + 1).isImmediate()) { 480 int Val = (int) MI->getOperand (i + 1).getImmedValue (); 481 if (Val != 0) { 482 O << ((Val >= 0) ? " + " : " - "); 483 O << ((Val >= 0) ? Val : -Val); 484 } 485 } else { 486 O << " + "; 487 printOperand (MI, i + 1); 488 } 489 if (brackets) O << "]"; 490} 491 492/// printMachineInstruction -- Print out a single SparcV8 LLVM instruction 493/// MI in GAS syntax to the current output stream. 494/// 495void V8Printer::printMachineInstruction(const MachineInstr *MI) { 496 unsigned Opcode = MI->getOpcode(); 497 const TargetInstrInfo &TII = *TM.getInstrInfo(); 498 const TargetInstrDescriptor &Desc = TII.get(Opcode); 499 500 // If it's a pseudo-instruction, comment it out. 501 if (isPseudoInstruction (MI)) 502 O << "! "; 503 504 O << Desc.Name << " "; 505 506 // Printing memory instructions is a special case. 507 // for loads: %dest = op %base, offset --> op [%base + offset], %dest 508 // for stores: op %base, offset, %src --> op %src, [%base + offset] 509 if (isLoadInstruction (MI)) { 510 printBaseOffsetPair (MI, 1); 511 O << ", "; 512 printOperand (MI, 0); 513 O << "\n"; 514 return; 515 } else if (isStoreInstruction (MI)) { 516 printOperand (MI, 2); 517 O << ", "; 518 printBaseOffsetPair (MI, 0); 519 O << "\n"; 520 return; 521 } else if (Opcode == V8::JMPLrr) { 522 printBaseOffsetPair (MI, 1, false); 523 O << ", "; 524 printOperand (MI, 0); 525 O << "\n"; 526 return; 527 } 528 529 // print non-immediate, non-register-def operands 530 // then print immediate operands 531 // then print register-def operands. 532 std::vector<int> print_order; 533 for (unsigned i = 0; i < MI->getNumOperands (); ++i) 534 if (!(MI->getOperand (i).isImmediate () 535 || (MI->getOperand (i).isRegister () 536 && MI->getOperand (i).isDef ()))) 537 print_order.push_back (i); 538 for (unsigned i = 0; i < MI->getNumOperands (); ++i) 539 if (MI->getOperand (i).isImmediate ()) 540 print_order.push_back (i); 541 for (unsigned i = 0; i < MI->getNumOperands (); ++i) 542 if (MI->getOperand (i).isRegister () && MI->getOperand (i).isDef ()) 543 print_order.push_back (i); 544 for (unsigned i = 0, e = print_order.size (); i != e; ++i) { 545 printOperand (MI, print_order[i]); 546 if (i != (print_order.size () - 1)) 547 O << ", "; 548 } 549 O << "\n"; 550} 551 552bool V8Printer::doInitialization(Module &M) { 553 Mang = new Mangler(M); 554 return false; // success 555} 556 557// SwitchSection - Switch to the specified section of the executable if we are 558// not already in it! 559// 560static void SwitchSection(std::ostream &OS, std::string &CurSection, 561 const char *NewSection) { 562 if (CurSection != NewSection) { 563 CurSection = NewSection; 564 if (!CurSection.empty()) 565 OS << "\t.section \"" << NewSection << "\"\n"; 566 } 567} 568 569bool V8Printer::doFinalization(Module &M) { 570 const TargetData &TD = TM.getTargetData(); 571 std::string CurSection; 572 573 // Print out module-level global variables here. 574 for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I) 575 if (I->hasInitializer()) { // External global require no code 576 O << "\n\n"; 577 std::string name = Mang->getValueName(I); 578 Constant *C = I->getInitializer(); 579 unsigned Size = TD.getTypeSize(C->getType()); 580 unsigned Align = TD.getTypeAlignment(C->getType()); 581 582 if (C->isNullValue() && 583 (I->hasLinkOnceLinkage() || I->hasInternalLinkage() || 584 I->hasWeakLinkage() /* FIXME: Verify correct */)) { 585 SwitchSection(O, CurSection, ".data"); 586 if (I->hasInternalLinkage()) 587 O << "\t.local " << name << "\n"; 588 589 O << "\t.comm " << name << "," << TD.getTypeSize(C->getType()) 590 << "," << (unsigned)TD.getTypeAlignment(C->getType()); 591 O << "\t\t! "; 592 WriteAsOperand(O, I, true, true, &M); 593 O << "\n"; 594 } else { 595 switch (I->getLinkage()) { 596 case GlobalValue::LinkOnceLinkage: 597 case GlobalValue::WeakLinkage: // FIXME: Verify correct for weak. 598 // Nonnull linkonce -> weak 599 O << "\t.weak " << name << "\n"; 600 SwitchSection(O, CurSection, ""); 601 O << "\t.section\t\".llvm.linkonce.d." << name << "\",\"aw\",@progbits\n"; 602 break; 603 604 case GlobalValue::AppendingLinkage: 605 // FIXME: appending linkage variables should go into a section of 606 // their name or something. For now, just emit them as external. 607 case GlobalValue::ExternalLinkage: 608 // If external or appending, declare as a global symbol 609 O << "\t.globl " << name << "\n"; 610 // FALL THROUGH 611 case GlobalValue::InternalLinkage: 612 if (C->isNullValue()) 613 SwitchSection(O, CurSection, ".bss"); 614 else 615 SwitchSection(O, CurSection, ".data"); 616 break; 617 } 618 619 O << "\t.align " << Align << "\n"; 620 O << "\t.type " << name << ",#object\n"; 621 O << "\t.size " << name << "," << Size << "\n"; 622 O << name << ":\t\t\t\t! "; 623 WriteAsOperand(O, I, true, true, &M); 624 O << " = "; 625 WriteAsOperand(O, C, false, false, &M); 626 O << "\n"; 627 emitGlobalConstant(C); 628 } 629 } 630 631 delete Mang; 632 return false; // success 633} 634