AsmMatcherEmitter.cpp revision db2ddb5dc57319eff249144f1d9a553a3278d2e0
1//===- AsmMatcherEmitter.cpp - Generate an assembly matcher ---------------===// 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 tablegen backend emits a target specifier matcher for converting parsed 11// assembly operands in the MCInst structures. 12// 13// The input to the target specific matcher is a list of literal tokens and 14// operands. The target specific parser should generally eliminate any syntax 15// which is not relevant for matching; for example, comma tokens should have 16// already been consumed and eliminated by the parser. Most instructions will 17// end up with a single literal token (the instruction name) and some number of 18// operands. 19// 20// Some example inputs, for X86: 21// 'addl' (immediate ...) (register ...) 22// 'add' (immediate ...) (memory ...) 23// 'call' '*' %epc 24// 25// The assembly matcher is responsible for converting this input into a precise 26// machine instruction (i.e., an instruction with a well defined encoding). This 27// mapping has several properties which complicate matching: 28// 29// - It may be ambiguous; many architectures can legally encode particular 30// variants of an instruction in different ways (for example, using a smaller 31// encoding for small immediates). Such ambiguities should never be 32// arbitrarily resolved by the assembler, the assembler is always responsible 33// for choosing the "best" available instruction. 34// 35// - It may depend on the subtarget or the assembler context. Instructions 36// which are invalid for the current mode, but otherwise unambiguous (e.g., 37// an SSE instruction in a file being assembled for i486) should be accepted 38// and rejected by the assembler front end. However, if the proper encoding 39// for an instruction is dependent on the assembler context then the matcher 40// is responsible for selecting the correct machine instruction for the 41// current mode. 42// 43// The core matching algorithm attempts to exploit the regularity in most 44// instruction sets to quickly determine the set of possibly matching 45// instructions, and the simplify the generated code. Additionally, this helps 46// to ensure that the ambiguities are intentionally resolved by the user. 47// 48// The matching is divided into two distinct phases: 49// 50// 1. Classification: Each operand is mapped to the unique set which (a) 51// contains it, and (b) is the largest such subset for which a single 52// instruction could match all members. 53// 54// For register classes, we can generate these subgroups automatically. For 55// arbitrary operands, we expect the user to define the classes and their 56// relations to one another (for example, 8-bit signed immediates as a 57// subset of 32-bit immediates). 58// 59// By partitioning the operands in this way, we guarantee that for any 60// tuple of classes, any single instruction must match either all or none 61// of the sets of operands which could classify to that tuple. 62// 63// In addition, the subset relation amongst classes induces a partial order 64// on such tuples, which we use to resolve ambiguities. 65// 66// FIXME: What do we do if a crazy case shows up where this is the wrong 67// resolution? 68// 69// 2. The input can now be treated as a tuple of classes (static tokens are 70// simple singleton sets). Each such tuple should generally map to a single 71// instruction (we currently ignore cases where this isn't true, whee!!!), 72// which we can emit a simple matcher for. 73// 74//===----------------------------------------------------------------------===// 75 76#include "AsmMatcherEmitter.h" 77#include "CodeGenTarget.h" 78#include "Record.h" 79#include "llvm/ADT/OwningPtr.h" 80#include "llvm/ADT/SmallVector.h" 81#include "llvm/ADT/STLExtras.h" 82#include "llvm/ADT/StringExtras.h" 83#include "llvm/Support/CommandLine.h" 84#include "llvm/Support/Debug.h" 85#include <list> 86#include <map> 87#include <set> 88using namespace llvm; 89 90namespace { 91static cl::opt<std::string> 92MatchPrefix("match-prefix", cl::init(""), 93 cl::desc("Only match instructions with the given prefix")); 94} 95 96/// FlattenVariants - Flatten an .td file assembly string by selecting the 97/// variant at index \arg N. 98static std::string FlattenVariants(const std::string &AsmString, 99 unsigned N) { 100 StringRef Cur = AsmString; 101 std::string Res = ""; 102 103 for (;;) { 104 // Find the start of the next variant string. 105 size_t VariantsStart = 0; 106 for (size_t e = Cur.size(); VariantsStart != e; ++VariantsStart) 107 if (Cur[VariantsStart] == '{' && 108 (VariantsStart == 0 || (Cur[VariantsStart-1] != '$' && 109 Cur[VariantsStart-1] != '\\'))) 110 break; 111 112 // Add the prefix to the result. 113 Res += Cur.slice(0, VariantsStart); 114 if (VariantsStart == Cur.size()) 115 break; 116 117 ++VariantsStart; // Skip the '{'. 118 119 // Scan to the end of the variants string. 120 size_t VariantsEnd = VariantsStart; 121 unsigned NestedBraces = 1; 122 for (size_t e = Cur.size(); VariantsEnd != e; ++VariantsEnd) { 123 if (Cur[VariantsEnd] == '}' && Cur[VariantsEnd-1] != '\\') { 124 if (--NestedBraces == 0) 125 break; 126 } else if (Cur[VariantsEnd] == '{') 127 ++NestedBraces; 128 } 129 130 // Select the Nth variant (or empty). 131 StringRef Selection = Cur.slice(VariantsStart, VariantsEnd); 132 for (unsigned i = 0; i != N; ++i) 133 Selection = Selection.split('|').second; 134 Res += Selection.split('|').first; 135 136 assert(VariantsEnd != Cur.size() && 137 "Unterminated variants in assembly string!"); 138 Cur = Cur.substr(VariantsEnd + 1); 139 } 140 141 return Res; 142} 143 144/// TokenizeAsmString - Tokenize a simplified assembly string. 145static void TokenizeAsmString(const StringRef &AsmString, 146 SmallVectorImpl<StringRef> &Tokens) { 147 unsigned Prev = 0; 148 bool InTok = true; 149 for (unsigned i = 0, e = AsmString.size(); i != e; ++i) { 150 switch (AsmString[i]) { 151 case '[': 152 case ']': 153 case '*': 154 case '!': 155 case ' ': 156 case '\t': 157 case ',': 158 if (InTok) { 159 Tokens.push_back(AsmString.slice(Prev, i)); 160 InTok = false; 161 } 162 if (!isspace(AsmString[i]) && AsmString[i] != ',') 163 Tokens.push_back(AsmString.substr(i, 1)); 164 Prev = i + 1; 165 break; 166 167 case '\\': 168 if (InTok) { 169 Tokens.push_back(AsmString.slice(Prev, i)); 170 InTok = false; 171 } 172 ++i; 173 assert(i != AsmString.size() && "Invalid quoted character"); 174 Tokens.push_back(AsmString.substr(i, 1)); 175 Prev = i + 1; 176 break; 177 178 case '$': { 179 // If this isn't "${", treat like a normal token. 180 if (i + 1 == AsmString.size() || AsmString[i + 1] != '{') { 181 if (InTok) { 182 Tokens.push_back(AsmString.slice(Prev, i)); 183 InTok = false; 184 } 185 Prev = i; 186 break; 187 } 188 189 if (InTok) { 190 Tokens.push_back(AsmString.slice(Prev, i)); 191 InTok = false; 192 } 193 194 StringRef::iterator End = 195 std::find(AsmString.begin() + i, AsmString.end(), '}'); 196 assert(End != AsmString.end() && "Missing brace in operand reference!"); 197 size_t EndPos = End - AsmString.begin(); 198 Tokens.push_back(AsmString.slice(i, EndPos+1)); 199 Prev = EndPos + 1; 200 i = EndPos; 201 break; 202 } 203 204 default: 205 InTok = true; 206 } 207 } 208 if (InTok && Prev != AsmString.size()) 209 Tokens.push_back(AsmString.substr(Prev)); 210} 211 212static bool IsAssemblerInstruction(const StringRef &Name, 213 const CodeGenInstruction &CGI, 214 const SmallVectorImpl<StringRef> &Tokens) { 215 // Ignore psuedo ops. 216 // 217 // FIXME: This is a hack. 218 if (const RecordVal *Form = CGI.TheDef->getValue("Form")) 219 if (Form->getValue()->getAsString() == "Pseudo") 220 return false; 221 222 // Ignore "PHI" node. 223 // 224 // FIXME: This is also a hack. 225 if (Name == "PHI") 226 return false; 227 228 // Ignore "Int_*" and "*_Int" instructions, which are internal aliases. 229 // 230 // FIXME: This is a total hack. 231 if (StringRef(Name).startswith("Int_") || StringRef(Name).endswith("_Int")) 232 return false; 233 234 // Ignore instructions with no .s string. 235 // 236 // FIXME: What are these? 237 if (CGI.AsmString.empty()) 238 return false; 239 240 // FIXME: Hack; ignore any instructions with a newline in them. 241 if (std::find(CGI.AsmString.begin(), 242 CGI.AsmString.end(), '\n') != CGI.AsmString.end()) 243 return false; 244 245 // Ignore instructions with attributes, these are always fake instructions for 246 // simplifying codegen. 247 // 248 // FIXME: Is this true? 249 // 250 // Also, we ignore instructions which reference the operand multiple times; 251 // this implies a constraint we would not currently honor. These are 252 // currently always fake instructions for simplifying codegen. 253 // 254 // FIXME: Encode this assumption in the .td, so we can error out here. 255 std::set<std::string> OperandNames; 256 for (unsigned i = 1, e = Tokens.size(); i < e; ++i) { 257 if (Tokens[i][0] == '$' && 258 std::find(Tokens[i].begin(), 259 Tokens[i].end(), ':') != Tokens[i].end()) { 260 DEBUG({ 261 errs() << "warning: '" << Name << "': " 262 << "ignoring instruction; operand with attribute '" 263 << Tokens[i] << "', \n"; 264 }); 265 return false; 266 } 267 268 if (Tokens[i][0] == '$' && !OperandNames.insert(Tokens[i]).second) { 269 DEBUG({ 270 errs() << "warning: '" << Name << "': " 271 << "ignoring instruction; tied operand '" 272 << Tokens[i] << "'\n"; 273 }); 274 return false; 275 } 276 } 277 278 return true; 279} 280 281namespace { 282 283/// ClassInfo - Helper class for storing the information about a particular 284/// class of operands which can be matched. 285struct ClassInfo { 286 enum ClassInfoKind { 287 Invalid = 0, ///< Invalid kind, for use as a sentinel value. 288 Token, ///< The class for a particular token. 289 Register, ///< A register class. 290 UserClass0 ///< The (first) user defined class, subsequent user defined 291 /// classes are UserClass0+1, and so on. 292 }; 293 294 /// Kind - The class kind, which is either a predefined kind, or (UserClass0 + 295 /// N) for the Nth user defined class. 296 unsigned Kind; 297 298 /// SuperClassKind - The super class kind for user classes. 299 unsigned SuperClassKind; 300 301 /// SuperClass - The super class, or 0. 302 ClassInfo *SuperClass; 303 304 /// Name - The full class name, suitable for use in an enum. 305 std::string Name; 306 307 /// ClassName - The unadorned generic name for this class (e.g., Token). 308 std::string ClassName; 309 310 /// ValueName - The name of the value this class represents; for a token this 311 /// is the literal token string, for an operand it is the TableGen class (or 312 /// empty if this is a derived class). 313 std::string ValueName; 314 315 /// PredicateMethod - The name of the operand method to test whether the 316 /// operand matches this class; this is not valid for Token kinds. 317 std::string PredicateMethod; 318 319 /// RenderMethod - The name of the operand method to add this operand to an 320 /// MCInst; this is not valid for Token kinds. 321 std::string RenderMethod; 322 323 /// isUserClass() - Check if this is a user defined class. 324 bool isUserClass() const { 325 return Kind >= UserClass0; 326 } 327 328 /// getRootClass - Return the root class of this one. 329 const ClassInfo *getRootClass() const { 330 const ClassInfo *CI = this; 331 while (CI->SuperClass) 332 CI = CI->SuperClass; 333 return CI; 334 } 335 336 /// operator< - Compare two classes. 337 bool operator<(const ClassInfo &RHS) const { 338 // Incompatible kinds are comparable for classes in disjoint hierarchies. 339 if (Kind != RHS.Kind && getRootClass() != RHS.getRootClass()) 340 return Kind < RHS.Kind; 341 342 switch (Kind) { 343 case Invalid: 344 assert(0 && "Invalid kind!"); 345 case Token: 346 // Tokens are comparable by value. 347 // 348 // FIXME: Compare by enum value. 349 return ValueName < RHS.ValueName; 350 351 default: 352 // This class preceeds the RHS if the RHS is a super class. 353 for (ClassInfo *Parent = SuperClass; Parent; Parent = Parent->SuperClass) 354 if (Parent == &RHS) 355 return true; 356 357 return false; 358 } 359 } 360}; 361 362/// InstructionInfo - Helper class for storing the necessary information for an 363/// instruction which is capable of being matched. 364struct InstructionInfo { 365 struct Operand { 366 /// The unique class instance this operand should match. 367 ClassInfo *Class; 368 369 /// The original operand this corresponds to, if any. 370 const CodeGenInstruction::OperandInfo *OperandInfo; 371 }; 372 373 /// InstrName - The target name for this instruction. 374 std::string InstrName; 375 376 /// Instr - The instruction this matches. 377 const CodeGenInstruction *Instr; 378 379 /// AsmString - The assembly string for this instruction (with variants 380 /// removed). 381 std::string AsmString; 382 383 /// Tokens - The tokenized assembly pattern that this instruction matches. 384 SmallVector<StringRef, 4> Tokens; 385 386 /// Operands - The operands that this instruction matches. 387 SmallVector<Operand, 4> Operands; 388 389 /// ConversionFnKind - The enum value which is passed to the generated 390 /// ConvertToMCInst to convert parsed operands into an MCInst for this 391 /// function. 392 std::string ConversionFnKind; 393 394 /// operator< - Compare two instructions. 395 bool operator<(const InstructionInfo &RHS) const { 396 if (Operands.size() != RHS.Operands.size()) 397 return Operands.size() < RHS.Operands.size(); 398 399 // Compare lexicographically by operand. The matcher validates that other 400 // orderings wouldn't be ambiguous using \see CouldMatchAmiguouslyWith(). 401 for (unsigned i = 0, e = Operands.size(); i != e; ++i) { 402 if (*Operands[i].Class < *RHS.Operands[i].Class) 403 return true; 404 if (*RHS.Operands[i].Class < *Operands[i].Class) 405 return false; 406 } 407 408 return false; 409 } 410 411 /// CouldMatchAmiguouslyWith - Check whether this instruction could 412 /// ambiguously match the same set of operands as \arg RHS (without being a 413 /// strictly superior match). 414 bool CouldMatchAmiguouslyWith(const InstructionInfo &RHS) { 415 // The number of operands is unambiguous. 416 if (Operands.size() != RHS.Operands.size()) 417 return false; 418 419 // Tokens and operand kinds are unambiguous (assuming a correct target 420 // specific parser). 421 for (unsigned i = 0, e = Operands.size(); i != e; ++i) 422 if (Operands[i].Class->Kind != RHS.Operands[i].Class->Kind || 423 Operands[i].Class->Kind == ClassInfo::Token) 424 if (*Operands[i].Class < *RHS.Operands[i].Class || 425 *RHS.Operands[i].Class < *Operands[i].Class) 426 return false; 427 428 // Otherwise, this operand could commute if all operands are equivalent, or 429 // there is a pair of operands that compare less than and a pair that 430 // compare greater than. 431 bool HasLT = false, HasGT = false; 432 for (unsigned i = 0, e = Operands.size(); i != e; ++i) { 433 if (*Operands[i].Class < *RHS.Operands[i].Class) 434 HasLT = true; 435 if (*RHS.Operands[i].Class < *Operands[i].Class) 436 HasGT = true; 437 } 438 439 return !(HasLT ^ HasGT); 440 } 441 442public: 443 void dump(); 444}; 445 446class AsmMatcherInfo { 447public: 448 /// The classes which are needed for matching. 449 std::vector<ClassInfo*> Classes; 450 451 /// The information on the instruction to match. 452 std::vector<InstructionInfo*> Instructions; 453 454private: 455 /// Map of token to class information which has already been constructed. 456 std::map<std::string, ClassInfo*> TokenClasses; 457 458 /// Map of operand name to class information which has already been 459 /// constructed. 460 std::map<std::string, ClassInfo*> OperandClasses; 461 462 /// Map of user class names to kind value. 463 std::map<std::string, unsigned> UserClasses; 464 465private: 466 /// getTokenClass - Lookup or create the class for the given token. 467 ClassInfo *getTokenClass(const StringRef &Token); 468 469 /// getUserClassKind - Lookup or create the kind value for the given class 470 /// name. 471 unsigned getUserClassKind(const StringRef &Name); 472 473 /// getOperandClass - Lookup or create the class for the given operand. 474 ClassInfo *getOperandClass(const StringRef &Token, 475 const CodeGenInstruction::OperandInfo &OI); 476 477public: 478 /// BuildInfo - Construct the various tables used during matching. 479 void BuildInfo(CodeGenTarget &Target); 480}; 481 482} 483 484void InstructionInfo::dump() { 485 errs() << InstrName << " -- " << "flattened:\"" << AsmString << '\"' 486 << ", tokens:["; 487 for (unsigned i = 0, e = Tokens.size(); i != e; ++i) { 488 errs() << Tokens[i]; 489 if (i + 1 != e) 490 errs() << ", "; 491 } 492 errs() << "]\n"; 493 494 for (unsigned i = 0, e = Operands.size(); i != e; ++i) { 495 Operand &Op = Operands[i]; 496 errs() << " op[" << i << "] = " << Op.Class->ClassName << " - "; 497 if (Op.Class->Kind == ClassInfo::Token) { 498 errs() << '\"' << Tokens[i] << "\"\n"; 499 continue; 500 } 501 502 const CodeGenInstruction::OperandInfo &OI = *Op.OperandInfo; 503 errs() << OI.Name << " " << OI.Rec->getName() 504 << " (" << OI.MIOperandNo << ", " << OI.MINumOperands << ")\n"; 505 } 506} 507 508static std::string getEnumNameForToken(const StringRef &Str) { 509 std::string Res; 510 511 for (StringRef::iterator it = Str.begin(), ie = Str.end(); it != ie; ++it) { 512 switch (*it) { 513 case '*': Res += "_STAR_"; break; 514 case '%': Res += "_PCT_"; break; 515 case ':': Res += "_COLON_"; break; 516 517 default: 518 if (isalnum(*it)) { 519 Res += *it; 520 } else { 521 Res += "_" + utostr((unsigned) *it) + "_"; 522 } 523 } 524 } 525 526 return Res; 527} 528 529ClassInfo *AsmMatcherInfo::getTokenClass(const StringRef &Token) { 530 ClassInfo *&Entry = TokenClasses[Token]; 531 532 if (!Entry) { 533 Entry = new ClassInfo(); 534 Entry->Kind = ClassInfo::Token; 535 Entry->ClassName = "Token"; 536 Entry->Name = "MCK_" + getEnumNameForToken(Token); 537 Entry->ValueName = Token; 538 Entry->PredicateMethod = "<invalid>"; 539 Entry->RenderMethod = "<invalid>"; 540 Classes.push_back(Entry); 541 } 542 543 return Entry; 544} 545 546unsigned AsmMatcherInfo::getUserClassKind(const StringRef &Name) { 547 unsigned &Entry = UserClasses[Name]; 548 549 if (!Entry) 550 Entry = ClassInfo::UserClass0 + UserClasses.size() - 1; 551 552 return Entry; 553} 554 555ClassInfo * 556AsmMatcherInfo::getOperandClass(const StringRef &Token, 557 const CodeGenInstruction::OperandInfo &OI) { 558 unsigned SuperClass = ClassInfo::Invalid; 559 std::string ClassName; 560 if (OI.Rec->isSubClassOf("RegisterClass")) { 561 ClassName = "Reg"; 562 } else { 563 try { 564 ClassName = OI.Rec->getValueAsString("ParserMatchClass"); 565 assert(ClassName != "Reg" && "'Reg' class name is reserved!"); 566 } catch(...) { 567 PrintError(OI.Rec->getLoc(), "operand has no match class!"); 568 ClassName = "Invalid"; 569 } 570 571 // Determine the super class. 572 try { 573 std::string SuperClassName = 574 OI.Rec->getValueAsString("ParserMatchSuperClass"); 575 SuperClass = getUserClassKind(SuperClassName); 576 } catch(...) { } 577 } 578 579 ClassInfo *&Entry = OperandClasses[ClassName]; 580 581 if (!Entry) { 582 Entry = new ClassInfo(); 583 if (ClassName == "Reg") { 584 Entry->Kind = ClassInfo::Register; 585 Entry->SuperClassKind = SuperClass; 586 } else { 587 Entry->Kind = getUserClassKind(ClassName); 588 Entry->SuperClassKind = SuperClass; 589 } 590 Entry->ClassName = ClassName; 591 Entry->Name = "MCK_" + ClassName; 592 Entry->ValueName = OI.Rec->getName(); 593 Entry->PredicateMethod = "is" + ClassName; 594 Entry->RenderMethod = "add" + ClassName + "Operands"; 595 Classes.push_back(Entry); 596 } else { 597 // Verify the super class matches. 598 assert(SuperClass == Entry->SuperClassKind && 599 "Cannot redefine super class kind!"); 600 } 601 602 return Entry; 603} 604 605void AsmMatcherInfo::BuildInfo(CodeGenTarget &Target) { 606 for (std::map<std::string, CodeGenInstruction>::const_iterator 607 it = Target.getInstructions().begin(), 608 ie = Target.getInstructions().end(); 609 it != ie; ++it) { 610 const CodeGenInstruction &CGI = it->second; 611 612 if (!StringRef(it->first).startswith(MatchPrefix)) 613 continue; 614 615 OwningPtr<InstructionInfo> II(new InstructionInfo); 616 617 II->InstrName = it->first; 618 II->Instr = &it->second; 619 II->AsmString = FlattenVariants(CGI.AsmString, 0); 620 621 TokenizeAsmString(II->AsmString, II->Tokens); 622 623 // Ignore instructions which shouldn't be matched. 624 if (!IsAssemblerInstruction(it->first, CGI, II->Tokens)) 625 continue; 626 627 for (unsigned i = 0, e = II->Tokens.size(); i != e; ++i) { 628 StringRef Token = II->Tokens[i]; 629 630 // Check for simple tokens. 631 if (Token[0] != '$') { 632 InstructionInfo::Operand Op; 633 Op.Class = getTokenClass(Token); 634 Op.OperandInfo = 0; 635 II->Operands.push_back(Op); 636 continue; 637 } 638 639 // Otherwise this is an operand reference. 640 StringRef OperandName; 641 if (Token[1] == '{') 642 OperandName = Token.substr(2, Token.size() - 3); 643 else 644 OperandName = Token.substr(1); 645 646 // Map this token to an operand. FIXME: Move elsewhere. 647 unsigned Idx; 648 try { 649 Idx = CGI.getOperandNamed(OperandName); 650 } catch(...) { 651 errs() << "error: unable to find operand: '" << OperandName << "'!\n"; 652 break; 653 } 654 655 const CodeGenInstruction::OperandInfo &OI = CGI.OperandList[Idx]; 656 InstructionInfo::Operand Op; 657 Op.Class = getOperandClass(Token, OI); 658 Op.OperandInfo = &OI; 659 II->Operands.push_back(Op); 660 } 661 662 // If we broke out, ignore the instruction. 663 if (II->Operands.size() != II->Tokens.size()) 664 continue; 665 666 Instructions.push_back(II.take()); 667 } 668 669 // Bind user super classes. 670 std::map<unsigned, ClassInfo*> UserClasses; 671 for (unsigned i = 0, e = Classes.size(); i != e; ++i) { 672 ClassInfo &CI = *Classes[i]; 673 if (CI.isUserClass()) 674 UserClasses[CI.Kind] = &CI; 675 } 676 677 for (unsigned i = 0, e = Classes.size(); i != e; ++i) { 678 ClassInfo &CI = *Classes[i]; 679 if (CI.isUserClass() && CI.SuperClassKind != ClassInfo::Invalid) { 680 CI.SuperClass = UserClasses[CI.SuperClassKind]; 681 assert(CI.SuperClass && "Missing super class definition!"); 682 } else { 683 CI.SuperClass = 0; 684 } 685 } 686 687 // Reorder classes so that classes preceed super classes. 688 std::sort(Classes.begin(), Classes.end(), less_ptr<ClassInfo>()); 689} 690 691static void EmitConvertToMCInst(CodeGenTarget &Target, 692 std::vector<InstructionInfo*> &Infos, 693 raw_ostream &OS) { 694 // Write the convert function to a separate stream, so we can drop it after 695 // the enum. 696 std::string ConvertFnBody; 697 raw_string_ostream CvtOS(ConvertFnBody); 698 699 // Function we have already generated. 700 std::set<std::string> GeneratedFns; 701 702 // Start the unified conversion function. 703 704 CvtOS << "static bool ConvertToMCInst(ConversionKind Kind, MCInst &Inst, " 705 << "unsigned Opcode,\n" 706 << " SmallVectorImpl<" 707 << Target.getName() << "Operand> &Operands) {\n"; 708 CvtOS << " Inst.setOpcode(Opcode);\n"; 709 CvtOS << " switch (Kind) {\n"; 710 CvtOS << " default:\n"; 711 712 // Start the enum, which we will generate inline. 713 714 OS << "// Unified function for converting operants to MCInst instances.\n\n"; 715 OS << "enum ConversionKind {\n"; 716 717 for (std::vector<InstructionInfo*>::const_iterator it = Infos.begin(), 718 ie = Infos.end(); it != ie; ++it) { 719 InstructionInfo &II = **it; 720 721 // Order the (class) operands by the order to convert them into an MCInst. 722 SmallVector<std::pair<unsigned, unsigned>, 4> MIOperandList; 723 for (unsigned i = 0, e = II.Operands.size(); i != e; ++i) { 724 InstructionInfo::Operand &Op = II.Operands[i]; 725 if (Op.OperandInfo) 726 MIOperandList.push_back(std::make_pair(Op.OperandInfo->MIOperandNo, i)); 727 } 728 std::sort(MIOperandList.begin(), MIOperandList.end()); 729 730 // Compute the total number of operands. 731 unsigned NumMIOperands = 0; 732 for (unsigned i = 0, e = II.Instr->OperandList.size(); i != e; ++i) { 733 const CodeGenInstruction::OperandInfo &OI = II.Instr->OperandList[i]; 734 NumMIOperands = std::max(NumMIOperands, 735 OI.MIOperandNo + OI.MINumOperands); 736 } 737 738 // Build the conversion function signature. 739 std::string Signature = "Convert"; 740 unsigned CurIndex = 0; 741 for (unsigned i = 0, e = MIOperandList.size(); i != e; ++i) { 742 InstructionInfo::Operand &Op = II.Operands[MIOperandList[i].second]; 743 assert(CurIndex <= Op.OperandInfo->MIOperandNo && 744 "Duplicate match for instruction operand!"); 745 746 Signature += "_"; 747 748 // Skip operands which weren't matched by anything, this occurs when the 749 // .td file encodes "implicit" operands as explicit ones. 750 // 751 // FIXME: This should be removed from the MCInst structure. 752 for (; CurIndex != Op.OperandInfo->MIOperandNo; ++CurIndex) 753 Signature += "Imp"; 754 755 Signature += Op.Class->ClassName; 756 Signature += utostr(Op.OperandInfo->MINumOperands); 757 Signature += "_" + utostr(MIOperandList[i].second); 758 759 CurIndex += Op.OperandInfo->MINumOperands; 760 } 761 762 // Add any trailing implicit operands. 763 for (; CurIndex != NumMIOperands; ++CurIndex) 764 Signature += "Imp"; 765 766 II.ConversionFnKind = Signature; 767 768 // Check if we have already generated this signature. 769 if (!GeneratedFns.insert(Signature).second) 770 continue; 771 772 // If not, emit it now. 773 774 // Add to the enum list. 775 OS << " " << Signature << ",\n"; 776 777 // And to the convert function. 778 CvtOS << " case " << Signature << ":\n"; 779 CurIndex = 0; 780 for (unsigned i = 0, e = MIOperandList.size(); i != e; ++i) { 781 InstructionInfo::Operand &Op = II.Operands[MIOperandList[i].second]; 782 783 // Add the implicit operands. 784 for (; CurIndex != Op.OperandInfo->MIOperandNo; ++CurIndex) 785 CvtOS << " Inst.addOperand(MCOperand::CreateReg(0));\n"; 786 787 CvtOS << " Operands[" << MIOperandList[i].second 788 << "]." << Op.Class->RenderMethod 789 << "(Inst, " << Op.OperandInfo->MINumOperands << ");\n"; 790 CurIndex += Op.OperandInfo->MINumOperands; 791 } 792 793 // And add trailing implicit operands. 794 for (; CurIndex != NumMIOperands; ++CurIndex) 795 CvtOS << " Inst.addOperand(MCOperand::CreateReg(0));\n"; 796 CvtOS << " break;\n"; 797 } 798 799 // Finish the convert function. 800 801 CvtOS << " }\n"; 802 CvtOS << " return false;\n"; 803 CvtOS << "}\n\n"; 804 805 // Finish the enum, and drop the convert function after it. 806 807 OS << " NumConversionVariants\n"; 808 OS << "};\n\n"; 809 810 OS << CvtOS.str(); 811} 812 813/// EmitMatchClassEnumeration - Emit the enumeration for match class kinds. 814static void EmitMatchClassEnumeration(CodeGenTarget &Target, 815 std::vector<ClassInfo*> &Infos, 816 raw_ostream &OS) { 817 OS << "namespace {\n\n"; 818 819 OS << "/// MatchClassKind - The kinds of classes which participate in\n" 820 << "/// instruction matching.\n"; 821 OS << "enum MatchClassKind {\n"; 822 OS << " InvalidMatchClass = 0,\n"; 823 for (std::vector<ClassInfo*>::iterator it = Infos.begin(), 824 ie = Infos.end(); it != ie; ++it) { 825 ClassInfo &CI = **it; 826 OS << " " << CI.Name << ", // "; 827 if (CI.Kind == ClassInfo::Token) { 828 OS << "'" << CI.ValueName << "'\n"; 829 } else if (CI.Kind == ClassInfo::Register) { 830 if (!CI.ValueName.empty()) 831 OS << "register class '" << CI.ValueName << "'\n"; 832 else 833 OS << "derived register class\n"; 834 } else { 835 OS << "user defined class '" << CI.ValueName << "'\n"; 836 } 837 } 838 OS << " NumMatchClassKinds\n"; 839 OS << "};\n\n"; 840 841 OS << "}\n\n"; 842} 843 844/// EmitClassifyOperand - Emit the function to classify an operand. 845static void EmitClassifyOperand(CodeGenTarget &Target, 846 std::vector<ClassInfo*> &Infos, 847 raw_ostream &OS) { 848 OS << "static MatchClassKind ClassifyOperand(" 849 << Target.getName() << "Operand &Operand) {\n"; 850 OS << " if (Operand.isToken())\n"; 851 OS << " return MatchTokenString(Operand.getToken());\n\n"; 852 for (std::vector<ClassInfo*>::iterator it = Infos.begin(), 853 ie = Infos.end(); it != ie; ++it) { 854 ClassInfo &CI = **it; 855 856 if (CI.Kind != ClassInfo::Token) { 857 OS << " // '" << CI.ClassName << "' class"; 858 if (CI.SuperClass) { 859 OS << ", subclass of '" << CI.SuperClass->ClassName << "'"; 860 assert(CI < *CI.SuperClass && "Invalid class relation!"); 861 } 862 OS << "\n"; 863 864 OS << " if (Operand." << CI.PredicateMethod << "()) {\n"; 865 866 // Validate subclass relationships. 867 if (CI.SuperClass) 868 OS << " assert(Operand." << CI.SuperClass->PredicateMethod 869 << "() && \"Invalid class relationship!\");\n"; 870 871 OS << " return " << CI.Name << ";\n\n"; 872 OS << " }"; 873 } 874 } 875 OS << " return InvalidMatchClass;\n"; 876 OS << "}\n\n"; 877} 878 879typedef std::pair<std::string, std::string> StringPair; 880 881/// FindFirstNonCommonLetter - Find the first character in the keys of the 882/// string pairs that is not shared across the whole set of strings. All 883/// strings are assumed to have the same length. 884static unsigned 885FindFirstNonCommonLetter(const std::vector<const StringPair*> &Matches) { 886 assert(!Matches.empty()); 887 for (unsigned i = 0, e = Matches[0]->first.size(); i != e; ++i) { 888 // Check to see if letter i is the same across the set. 889 char Letter = Matches[0]->first[i]; 890 891 for (unsigned str = 0, e = Matches.size(); str != e; ++str) 892 if (Matches[str]->first[i] != Letter) 893 return i; 894 } 895 896 return Matches[0]->first.size(); 897} 898 899/// EmitStringMatcherForChar - Given a set of strings that are known to be the 900/// same length and whose characters leading up to CharNo are the same, emit 901/// code to verify that CharNo and later are the same. 902/// 903/// \return - True if control can leave the emitted code fragment. 904static bool EmitStringMatcherForChar(const std::string &StrVariableName, 905 const std::vector<const StringPair*> &Matches, 906 unsigned CharNo, unsigned IndentCount, 907 raw_ostream &OS) { 908 assert(!Matches.empty() && "Must have at least one string to match!"); 909 std::string Indent(IndentCount*2+4, ' '); 910 911 // If we have verified that the entire string matches, we're done: output the 912 // matching code. 913 if (CharNo == Matches[0]->first.size()) { 914 assert(Matches.size() == 1 && "Had duplicate keys to match on"); 915 916 // FIXME: If Matches[0].first has embeded \n, this will be bad. 917 OS << Indent << Matches[0]->second << "\t // \"" << Matches[0]->first 918 << "\"\n"; 919 return false; 920 } 921 922 // Bucket the matches by the character we are comparing. 923 std::map<char, std::vector<const StringPair*> > MatchesByLetter; 924 925 for (unsigned i = 0, e = Matches.size(); i != e; ++i) 926 MatchesByLetter[Matches[i]->first[CharNo]].push_back(Matches[i]); 927 928 929 // If we have exactly one bucket to match, see how many characters are common 930 // across the whole set and match all of them at once. 931 if (MatchesByLetter.size() == 1) { 932 unsigned FirstNonCommonLetter = FindFirstNonCommonLetter(Matches); 933 unsigned NumChars = FirstNonCommonLetter-CharNo; 934 935 // Emit code to break out if the prefix doesn't match. 936 if (NumChars == 1) { 937 // Do the comparison with if (Str[1] != 'f') 938 // FIXME: Need to escape general characters. 939 OS << Indent << "if (" << StrVariableName << "[" << CharNo << "] != '" 940 << Matches[0]->first[CharNo] << "')\n"; 941 OS << Indent << " break;\n"; 942 } else { 943 // Do the comparison with if (Str.substr(1,3) != "foo"). 944 // FIXME: Need to escape general strings. 945 OS << Indent << "if (" << StrVariableName << ".substr(" << CharNo << "," 946 << NumChars << ") != \""; 947 OS << Matches[0]->first.substr(CharNo, NumChars) << "\")\n"; 948 OS << Indent << " break;\n"; 949 } 950 951 return EmitStringMatcherForChar(StrVariableName, Matches, 952 FirstNonCommonLetter, IndentCount, OS); 953 } 954 955 // Otherwise, we have multiple possible things, emit a switch on the 956 // character. 957 OS << Indent << "switch (" << StrVariableName << "[" << CharNo << "]) {\n"; 958 OS << Indent << "default: break;\n"; 959 960 for (std::map<char, std::vector<const StringPair*> >::iterator LI = 961 MatchesByLetter.begin(), E = MatchesByLetter.end(); LI != E; ++LI) { 962 // TODO: escape hard stuff (like \n) if we ever care about it. 963 OS << Indent << "case '" << LI->first << "':\t // " 964 << LI->second.size() << " strings to match.\n"; 965 if (EmitStringMatcherForChar(StrVariableName, LI->second, CharNo+1, 966 IndentCount+1, OS)) 967 OS << Indent << " break;\n"; 968 } 969 970 OS << Indent << "}\n"; 971 return true; 972} 973 974 975/// EmitStringMatcher - Given a list of strings and code to execute when they 976/// match, output a simple switch tree to classify the input string. 977/// 978/// If a match is found, the code in Vals[i].second is executed; control must 979/// not exit this code fragment. If nothing matches, execution falls through. 980/// 981/// \param StrVariableName - The name of the variable to test. 982static void EmitStringMatcher(const std::string &StrVariableName, 983 const std::vector<StringPair> &Matches, 984 raw_ostream &OS) { 985 // First level categorization: group strings by length. 986 std::map<unsigned, std::vector<const StringPair*> > MatchesByLength; 987 988 for (unsigned i = 0, e = Matches.size(); i != e; ++i) 989 MatchesByLength[Matches[i].first.size()].push_back(&Matches[i]); 990 991 // Output a switch statement on length and categorize the elements within each 992 // bin. 993 OS << " switch (" << StrVariableName << ".size()) {\n"; 994 OS << " default: break;\n"; 995 996 for (std::map<unsigned, std::vector<const StringPair*> >::iterator LI = 997 MatchesByLength.begin(), E = MatchesByLength.end(); LI != E; ++LI) { 998 OS << " case " << LI->first << ":\t // " << LI->second.size() 999 << " strings to match.\n"; 1000 if (EmitStringMatcherForChar(StrVariableName, LI->second, 0, 0, OS)) 1001 OS << " break;\n"; 1002 } 1003 1004 OS << " }\n"; 1005} 1006 1007 1008/// EmitMatchTokenString - Emit the function to match a token string to the 1009/// appropriate match class value. 1010static void EmitMatchTokenString(CodeGenTarget &Target, 1011 std::vector<ClassInfo*> &Infos, 1012 raw_ostream &OS) { 1013 // Construct the match list. 1014 std::vector<StringPair> Matches; 1015 for (std::vector<ClassInfo*>::iterator it = Infos.begin(), 1016 ie = Infos.end(); it != ie; ++it) { 1017 ClassInfo &CI = **it; 1018 1019 if (CI.Kind == ClassInfo::Token) 1020 Matches.push_back(StringPair(CI.ValueName, "return " + CI.Name + ";")); 1021 } 1022 1023 OS << "static MatchClassKind MatchTokenString(const StringRef &Name) {\n"; 1024 1025 EmitStringMatcher("Name", Matches, OS); 1026 1027 OS << " return InvalidMatchClass;\n"; 1028 OS << "}\n\n"; 1029} 1030 1031/// EmitMatchRegisterName - Emit the function to match a string to the target 1032/// specific register enum. 1033static void EmitMatchRegisterName(CodeGenTarget &Target, Record *AsmParser, 1034 raw_ostream &OS) { 1035 // Construct the match list. 1036 std::vector<StringPair> Matches; 1037 for (unsigned i = 0, e = Target.getRegisters().size(); i != e; ++i) { 1038 const CodeGenRegister &Reg = Target.getRegisters()[i]; 1039 if (Reg.TheDef->getValueAsString("AsmName").empty()) 1040 continue; 1041 1042 Matches.push_back(StringPair(Reg.TheDef->getValueAsString("AsmName"), 1043 "return " + utostr(i + 1) + ";")); 1044 } 1045 1046 OS << "unsigned " << Target.getName() 1047 << AsmParser->getValueAsString("AsmParserClassName") 1048 << "::MatchRegisterName(const StringRef &Name) {\n"; 1049 1050 EmitStringMatcher("Name", Matches, OS); 1051 1052 OS << " return 0;\n"; 1053 OS << "}\n\n"; 1054} 1055 1056void AsmMatcherEmitter::run(raw_ostream &OS) { 1057 CodeGenTarget Target; 1058 Record *AsmParser = Target.getAsmParser(); 1059 std::string ClassName = AsmParser->getValueAsString("AsmParserClassName"); 1060 1061 EmitSourceFileHeader("Assembly Matcher Source Fragment", OS); 1062 1063 // Emit the function to match a register name to number. 1064 EmitMatchRegisterName(Target, AsmParser, OS); 1065 1066 // Compute the information on the instructions to match. 1067 AsmMatcherInfo Info; 1068 Info.BuildInfo(Target); 1069 1070 // Sort the instruction table using the partial order on classes. 1071 std::sort(Info.Instructions.begin(), Info.Instructions.end(), 1072 less_ptr<InstructionInfo>()); 1073 1074 DEBUG_WITH_TYPE("instruction_info", { 1075 for (std::vector<InstructionInfo*>::iterator 1076 it = Info.Instructions.begin(), ie = Info.Instructions.end(); 1077 it != ie; ++it) 1078 (*it)->dump(); 1079 }); 1080 1081 // Check for ambiguous instructions. 1082 unsigned NumAmbiguous = 0; 1083 for (unsigned i = 0, e = Info.Instructions.size(); i != e; ++i) { 1084 for (unsigned j = i + 1; j != e; ++j) { 1085 InstructionInfo &A = *Info.Instructions[i]; 1086 InstructionInfo &B = *Info.Instructions[j]; 1087 1088 if (A.CouldMatchAmiguouslyWith(B)) { 1089 DEBUG_WITH_TYPE("ambiguous_instrs", { 1090 errs() << "warning: ambiguous instruction match:\n"; 1091 A.dump(); 1092 errs() << "\nis incomparable with:\n"; 1093 B.dump(); 1094 errs() << "\n\n"; 1095 }); 1096 ++NumAmbiguous; 1097 } 1098 } 1099 } 1100 if (NumAmbiguous) 1101 DEBUG_WITH_TYPE("ambiguous_instrs", { 1102 errs() << "warning: " << NumAmbiguous 1103 << " ambiguous instructions!\n"; 1104 }); 1105 1106 // Generate the unified function to convert operands into an MCInst. 1107 EmitConvertToMCInst(Target, Info.Instructions, OS); 1108 1109 // Emit the enumeration for classes which participate in matching. 1110 EmitMatchClassEnumeration(Target, Info.Classes, OS); 1111 1112 // Emit the routine to match token strings to their match class. 1113 EmitMatchTokenString(Target, Info.Classes, OS); 1114 1115 // Emit the routine to classify an operand. 1116 EmitClassifyOperand(Target, Info.Classes, OS); 1117 1118 // Finally, build the match function. 1119 1120 size_t MaxNumOperands = 0; 1121 for (std::vector<InstructionInfo*>::const_iterator it = 1122 Info.Instructions.begin(), ie = Info.Instructions.end(); 1123 it != ie; ++it) 1124 MaxNumOperands = std::max(MaxNumOperands, (*it)->Operands.size()); 1125 1126 OS << "bool " << Target.getName() << ClassName 1127 << "::MatchInstruction(" 1128 << "SmallVectorImpl<" << Target.getName() << "Operand> &Operands, " 1129 << "MCInst &Inst) {\n"; 1130 1131 // Emit the static match table; unused classes get initalized to 0 which is 1132 // guaranteed to be InvalidMatchClass. 1133 // 1134 // FIXME: We can reduce the size of this table very easily. First, we change 1135 // it so that store the kinds in separate bit-fields for each index, which 1136 // only needs to be the max width used for classes at that index (we also need 1137 // to reject based on this during classification). If we then make sure to 1138 // order the match kinds appropriately (putting mnemonics last), then we 1139 // should only end up using a few bits for each class, especially the ones 1140 // following the mnemonic. 1141 OS << " static const struct MatchEntry {\n"; 1142 OS << " unsigned Opcode;\n"; 1143 OS << " ConversionKind ConvertFn;\n"; 1144 OS << " MatchClassKind Classes[" << MaxNumOperands << "];\n"; 1145 OS << " } MatchTable[" << Info.Instructions.size() << "] = {\n"; 1146 1147 for (std::vector<InstructionInfo*>::const_iterator it = 1148 Info.Instructions.begin(), ie = Info.Instructions.end(); 1149 it != ie; ++it) { 1150 InstructionInfo &II = **it; 1151 1152 OS << " { " << Target.getName() << "::" << II.InstrName 1153 << ", " << II.ConversionFnKind << ", { "; 1154 for (unsigned i = 0, e = II.Operands.size(); i != e; ++i) { 1155 InstructionInfo::Operand &Op = II.Operands[i]; 1156 1157 if (i) OS << ", "; 1158 OS << Op.Class->Name; 1159 } 1160 OS << " } },\n"; 1161 } 1162 1163 OS << " };\n\n"; 1164 1165 // Emit code to compute the class list for this operand vector. 1166 OS << " // Eliminate obvious mismatches.\n"; 1167 OS << " if (Operands.size() > " << MaxNumOperands << ")\n"; 1168 OS << " return true;\n\n"; 1169 1170 OS << " // Compute the class list for this operand vector.\n"; 1171 OS << " MatchClassKind Classes[" << MaxNumOperands << "];\n"; 1172 OS << " for (unsigned i = 0, e = Operands.size(); i != e; ++i) {\n"; 1173 OS << " Classes[i] = ClassifyOperand(Operands[i]);\n\n"; 1174 1175 OS << " // Check for invalid operands before matching.\n"; 1176 OS << " if (Classes[i] == InvalidMatchClass)\n"; 1177 OS << " return true;\n"; 1178 OS << " }\n\n"; 1179 1180 OS << " // Mark unused classes.\n"; 1181 OS << " for (unsigned i = Operands.size(), e = " << MaxNumOperands << "; " 1182 << "i != e; ++i)\n"; 1183 OS << " Classes[i] = InvalidMatchClass;\n\n"; 1184 1185 // Emit code to search the table. 1186 OS << " // Search the table.\n"; 1187 OS << " for (const MatchEntry *it = MatchTable, " 1188 << "*ie = MatchTable + " << Info.Instructions.size() 1189 << "; it != ie; ++it) {\n"; 1190 for (unsigned i = 0; i != MaxNumOperands; ++i) { 1191 OS << " if (Classes[" << i << "] != it->Classes[" << i << "])\n"; 1192 OS << " continue;\n"; 1193 } 1194 OS << "\n"; 1195 OS << " return ConvertToMCInst(it->ConvertFn, Inst, " 1196 << "it->Opcode, Operands);\n"; 1197 OS << " }\n\n"; 1198 1199 OS << " return true;\n"; 1200 OS << "}\n\n"; 1201} 1202