1 //===- AsmWriterEmitter.cpp - Generate an assembly writer -----------------===//
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 tablegen backend is emits an assembly printer for the current target.
11 // Note that this is currently fairly skeletal, but will grow over time.
13 //===----------------------------------------------------------------------===//
15 #include "AsmWriterEmitter.h"
16 #include "CodeGenTarget.h"
18 #include "llvm/ADT/StringExtras.h"
19 #include "llvm/Support/Debug.h"
20 #include "llvm/Support/MathExtras.h"
26 static bool isIdentChar(char C) {
27 return (C >= 'a' && C <= 'z') ||
28 (C >= 'A' && C <= 'Z') ||
29 (C >= '0' && C <= '9') ||
33 // This should be an anon namespace, this works around a GCC warning.
35 struct AsmWriterOperand {
38 isMachineInstrOperand,
39 isLiteralStatementOperand
42 /// Str - For isLiteralTextOperand, this IS the literal text. For
43 /// isMachineInstrOperand, this is the PrinterMethodName for the operand.
46 /// MiOpNo - For isMachineInstrOperand, this is the operand number of the
47 /// machine instruction.
50 /// MiModifier - For isMachineInstrOperand, this is the modifier string for
51 /// an operand, specified with syntax like ${opname:modifier}.
52 std::string MiModifier;
54 // To make VS STL happy
55 AsmWriterOperand(OpType op = isLiteralTextOperand):OperandType(op) {}
57 AsmWriterOperand(const std::string &LitStr,
58 OpType op = isLiteralTextOperand)
59 : OperandType(op), Str(LitStr) {}
61 AsmWriterOperand(const std::string &Printer, unsigned OpNo,
62 const std::string &Modifier,
63 OpType op = isMachineInstrOperand)
64 : OperandType(op), Str(Printer), MIOpNo(OpNo),
65 MiModifier(Modifier) {}
67 bool operator!=(const AsmWriterOperand &Other) const {
68 if (OperandType != Other.OperandType || Str != Other.Str) return true;
69 if (OperandType == isMachineInstrOperand)
70 return MIOpNo != Other.MIOpNo || MiModifier != Other.MiModifier;
73 bool operator==(const AsmWriterOperand &Other) const {
74 return !operator!=(Other);
77 /// getCode - Return the code that prints this operand.
78 std::string getCode() const;
85 std::vector<AsmWriterOperand> Operands;
86 const CodeGenInstruction *CGI;
88 /// MAX_GROUP_NESTING_LEVEL - The maximum number of group nesting
89 /// levels we ever expect to see in an asm operand.
90 static const int MAX_GROUP_NESTING_LEVEL = 10;
92 /// GroupLevel - The level of nesting of the current operand
93 /// group, such as [reg + (reg + offset)]. -1 means we are not in
97 /// GroupDelim - Remember the delimeter for a group operand.
98 char GroupDelim[MAX_GROUP_NESTING_LEVEL];
100 /// InGroup - Determine whether we are in the middle of an
102 bool InGroup() const { return GroupLevel != -1; }
104 AsmWriterInst(const CodeGenInstruction &CGI, unsigned Variant);
106 /// MatchesAllButOneOp - If this instruction is exactly identical to the
107 /// specified instruction except for one differing operand, return the
108 /// differing operand number. Otherwise return ~0.
109 unsigned MatchesAllButOneOp(const AsmWriterInst &Other) const;
112 void AddLiteralString(const std::string &Str) {
113 // If the last operand was already a literal text string, append this to
114 // it, otherwise add a new operand.
116 std::string::size_type SearchStart = 0;
117 std::string::size_type SpaceStartPos = std::string::npos;
119 // Search for whitespace and replace with calls to set the
121 SpaceStartPos = Str.find_first_of(" \t", SearchStart);
122 // Assume grouped text is one operand.
123 std::string::size_type StartDelimPos = Str.find_first_of("[{(", SearchStart);
125 SearchStart = std::string::npos;
127 if (StartDelimPos != std::string::npos) {
129 assert(GroupLevel < MAX_GROUP_NESTING_LEVEL
130 && "Exceeded maximum operand group nesting level");
131 GroupDelim[GroupLevel] = Str[StartDelimPos];
132 if (SpaceStartPos != std::string::npos &&
133 SpaceStartPos > StartDelimPos) {
134 // This space doesn't count.
135 SpaceStartPos = std::string::npos;
140 // Find the end delimiter.
141 char EndDelim = (GroupDelim[GroupLevel] == '{' ? '}' :
142 (GroupDelim[GroupLevel] == '(' ? ')' : ']'));
143 std::string::size_type EndDelimSearchStart =
144 StartDelimPos == std::string::npos ? 0 : StartDelimPos+1;
145 std::string::size_type EndDelimPos = Str.find(EndDelim,
146 EndDelimSearchStart);
147 SearchStart = EndDelimPos;
148 if (EndDelimPos != std::string::npos) {
150 SearchStart = EndDelimPos + 1;
152 assert(GroupLevel > -2 && "Too many end delimeters!");
155 SpaceStartPos = std::string::npos;
157 } while (SearchStart != std::string::npos);
160 if (SpaceStartPos != std::string::npos) {
161 std::string::size_type SpaceEndPos =
162 Str.find_first_not_of(" \t", SpaceStartPos+1);
163 if (SpaceStartPos != 0) {
164 // Emit the first part of the string.
165 AddLiteralString(Str.substr(0, SpaceStartPos));
169 "O.PadToColumn(TAI->getOperandColumn(OperandColumn++), 1);\n",
170 AsmWriterOperand::isLiteralStatementOperand));
171 if (SpaceEndPos != std::string::npos) {
172 // Emit the last part of the string.
173 AddLiteralString(Str.substr(SpaceEndPos));
175 // We've emitted the whole string.
179 if (!Operands.empty() &&
180 Operands.back().OperandType == AsmWriterOperand::isLiteralTextOperand)
181 Operands.back().Str.append(Str);
183 Operands.push_back(AsmWriterOperand(Str));
189 std::string AsmWriterOperand::getCode() const {
190 if (OperandType == isLiteralTextOperand)
191 return "O << \"" + Str + "\"; ";
193 if (OperandType == isLiteralStatementOperand) {
197 if (OperandType == isLiteralStatementOperand) {
201 if (OperandType == isLiteralStatementOperand) {
205 std::string Result = Str + "(MI";
207 Result += ", " + utostr(MIOpNo);
208 if (!MiModifier.empty())
209 Result += ", \"" + MiModifier + '"';
210 return Result + "); ";
214 /// ParseAsmString - Parse the specified Instruction's AsmString into this
217 AsmWriterInst::AsmWriterInst(const CodeGenInstruction &CGI, unsigned Variant)
220 unsigned CurVariant = ~0U; // ~0 if we are outside a {.|.|.} region, other #.
222 // NOTE: Any extensions to this code need to be mirrored in the
223 // AsmPrinter::printInlineAsm code that executes as compile time (assuming
224 // that inline asm strings should also get the new feature)!
225 const std::string &AsmString = CGI.AsmString;
226 std::string::size_type LastEmitted = 0;
227 while (LastEmitted != AsmString.size()) {
228 std::string::size_type DollarPos =
229 AsmString.find_first_of("${|}\\", LastEmitted);
230 if (DollarPos == std::string::npos) DollarPos = AsmString.size();
232 // Emit a constant string fragment.
233 if (DollarPos != LastEmitted) {
234 if (CurVariant == Variant || CurVariant == ~0U) {
235 for (; LastEmitted != DollarPos; ++LastEmitted)
236 switch (AsmString[LastEmitted]) {
237 case '\n': AddLiteralString("\\n"); break;
238 case '\t': AddLiteralString("\\t"); break;
239 case '"': AddLiteralString("\\\""); break;
240 case '\\': AddLiteralString("\\\\"); break;
242 AddLiteralString(std::string(1, AsmString[LastEmitted]));
246 LastEmitted = DollarPos;
248 } else if (AsmString[DollarPos] == '\\') {
249 if (DollarPos+1 != AsmString.size() &&
250 (CurVariant == Variant || CurVariant == ~0U)) {
251 if (AsmString[DollarPos+1] == 'n') {
252 AddLiteralString("\\n");
253 } else if (AsmString[DollarPos+1] == 't') {
254 AddLiteralString("\\t");
255 } else if (std::string("${|}\\").find(AsmString[DollarPos+1])
256 != std::string::npos) {
257 AddLiteralString(std::string(1, AsmString[DollarPos+1]));
259 throw "Non-supported escaped character found in instruction '" +
260 CGI.TheDef->getName() + "'!";
262 LastEmitted = DollarPos+2;
265 } else if (AsmString[DollarPos] == '{') {
266 if (CurVariant != ~0U)
267 throw "Nested variants found for instruction '" +
268 CGI.TheDef->getName() + "'!";
269 LastEmitted = DollarPos+1;
270 CurVariant = 0; // We are now inside of the variant!
271 } else if (AsmString[DollarPos] == '|') {
272 if (CurVariant == ~0U)
273 throw "'|' character found outside of a variant in instruction '"
274 + CGI.TheDef->getName() + "'!";
277 } else if (AsmString[DollarPos] == '}') {
278 if (CurVariant == ~0U)
279 throw "'}' character found outside of a variant in instruction '"
280 + CGI.TheDef->getName() + "'!";
283 } else if (DollarPos+1 != AsmString.size() &&
284 AsmString[DollarPos+1] == '$') {
285 if (CurVariant == Variant || CurVariant == ~0U)
286 AddLiteralString("$"); // "$$" -> $
287 LastEmitted = DollarPos+2;
289 // Get the name of the variable.
290 std::string::size_type VarEnd = DollarPos+1;
292 // handle ${foo}bar as $foo by detecting whether the character following
293 // the dollar sign is a curly brace. If so, advance VarEnd and DollarPos
294 // so the variable name does not contain the leading curly brace.
295 bool hasCurlyBraces = false;
296 if (VarEnd < AsmString.size() && '{' == AsmString[VarEnd]) {
297 hasCurlyBraces = true;
302 while (VarEnd < AsmString.size() && isIdentChar(AsmString[VarEnd]))
304 std::string VarName(AsmString.begin()+DollarPos+1,
305 AsmString.begin()+VarEnd);
307 // Modifier - Support ${foo:modifier} syntax, where "modifier" is passed
308 // into printOperand. Also support ${:feature}, which is passed into
310 std::string Modifier;
312 // In order to avoid starting the next string at the terminating curly
313 // brace, advance the end position past it if we found an opening curly
315 if (hasCurlyBraces) {
316 if (VarEnd >= AsmString.size())
317 throw "Reached end of string before terminating curly brace in '"
318 + CGI.TheDef->getName() + "'";
320 // Look for a modifier string.
321 if (AsmString[VarEnd] == ':') {
323 if (VarEnd >= AsmString.size())
324 throw "Reached end of string before terminating curly brace in '"
325 + CGI.TheDef->getName() + "'";
327 unsigned ModifierStart = VarEnd;
328 while (VarEnd < AsmString.size() && isIdentChar(AsmString[VarEnd]))
330 Modifier = std::string(AsmString.begin()+ModifierStart,
331 AsmString.begin()+VarEnd);
332 if (Modifier.empty())
333 throw "Bad operand modifier name in '"+ CGI.TheDef->getName() + "'";
336 if (AsmString[VarEnd] != '}')
337 throw "Variable name beginning with '{' did not end with '}' in '"
338 + CGI.TheDef->getName() + "'";
341 if (VarName.empty() && Modifier.empty())
342 throw "Stray '$' in '" + CGI.TheDef->getName() +
343 "' asm string, maybe you want $$?";
345 if (VarName.empty()) {
346 // Just a modifier, pass this into PrintSpecial.
347 Operands.push_back(AsmWriterOperand("PrintSpecial", ~0U, Modifier));
349 // Otherwise, normal operand.
350 unsigned OpNo = CGI.getOperandNamed(VarName);
351 CodeGenInstruction::OperandInfo OpInfo = CGI.OperandList[OpNo];
353 if (CurVariant == Variant || CurVariant == ~0U) {
354 unsigned MIOp = OpInfo.MIOperandNo;
355 Operands.push_back(AsmWriterOperand(OpInfo.PrinterMethodName, MIOp,
359 LastEmitted = VarEnd;
364 /// MatchesAllButOneOp - If this instruction is exactly identical to the
365 /// specified instruction except for one differing operand, return the differing
366 /// operand number. If more than one operand mismatches, return ~1, otherwise
367 /// if the instructions are identical return ~0.
368 unsigned AsmWriterInst::MatchesAllButOneOp(const AsmWriterInst &Other)const{
369 if (Operands.size() != Other.Operands.size()) return ~1;
371 unsigned MismatchOperand = ~0U;
372 for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
373 if (Operands[i] != Other.Operands[i]) {
374 if (MismatchOperand != ~0U) // Already have one mismatch?
380 return MismatchOperand;
383 static void PrintCases(std::vector<std::pair<std::string,
384 AsmWriterOperand> > &OpsToPrint, raw_ostream &O) {
385 O << " case " << OpsToPrint.back().first << ": ";
386 AsmWriterOperand TheOp = OpsToPrint.back().second;
387 OpsToPrint.pop_back();
389 // Check to see if any other operands are identical in this list, and if so,
390 // emit a case label for them.
391 for (unsigned i = OpsToPrint.size(); i != 0; --i)
392 if (OpsToPrint[i-1].second == TheOp) {
393 O << "\n case " << OpsToPrint[i-1].first << ": ";
394 OpsToPrint.erase(OpsToPrint.begin()+i-1);
397 // Finally, emit the code.
398 O << TheOp.getCode();
403 /// EmitInstructions - Emit the last instruction in the vector and any other
404 /// instructions that are suitably similar to it.
405 static void EmitInstructions(std::vector<AsmWriterInst> &Insts,
407 AsmWriterInst FirstInst = Insts.back();
410 std::vector<AsmWriterInst> SimilarInsts;
411 unsigned DifferingOperand = ~0;
412 for (unsigned i = Insts.size(); i != 0; --i) {
413 unsigned DiffOp = Insts[i-1].MatchesAllButOneOp(FirstInst);
415 if (DifferingOperand == ~0U) // First match!
416 DifferingOperand = DiffOp;
418 // If this differs in the same operand as the rest of the instructions in
419 // this class, move it to the SimilarInsts list.
420 if (DifferingOperand == DiffOp || DiffOp == ~0U) {
421 SimilarInsts.push_back(Insts[i-1]);
422 Insts.erase(Insts.begin()+i-1);
427 O << " case " << FirstInst.CGI->Namespace << "::"
428 << FirstInst.CGI->TheDef->getName() << ":\n";
429 for (unsigned i = 0, e = SimilarInsts.size(); i != e; ++i)
430 O << " case " << SimilarInsts[i].CGI->Namespace << "::"
431 << SimilarInsts[i].CGI->TheDef->getName() << ":\n";
432 for (unsigned i = 0, e = FirstInst.Operands.size(); i != e; ++i) {
433 if (i != DifferingOperand) {
434 // If the operand is the same for all instructions, just print it.
435 O << " " << FirstInst.Operands[i].getCode();
437 // If this is the operand that varies between all of the instructions,
438 // emit a switch for just this operand now.
439 O << " switch (MI->getOpcode()) {\n";
440 std::vector<std::pair<std::string, AsmWriterOperand> > OpsToPrint;
441 OpsToPrint.push_back(std::make_pair(FirstInst.CGI->Namespace + "::" +
442 FirstInst.CGI->TheDef->getName(),
443 FirstInst.Operands[i]));
445 for (unsigned si = 0, e = SimilarInsts.size(); si != e; ++si) {
446 AsmWriterInst &AWI = SimilarInsts[si];
447 OpsToPrint.push_back(std::make_pair(AWI.CGI->Namespace+"::"+
448 AWI.CGI->TheDef->getName(),
451 std::reverse(OpsToPrint.begin(), OpsToPrint.end());
452 while (!OpsToPrint.empty())
453 PrintCases(OpsToPrint, O);
458 O << " EmitComments(*MI);\n";
459 // Print the final newline
460 O << " O << \"\\n\";\n";
464 void AsmWriterEmitter::
465 FindUniqueOperandCommands(std::vector<std::string> &UniqueOperandCommands,
466 std::vector<unsigned> &InstIdxs,
467 std::vector<unsigned> &InstOpsUsed) const {
468 InstIdxs.assign(NumberedInstructions.size(), ~0U);
470 // This vector parallels UniqueOperandCommands, keeping track of which
471 // instructions each case are used for. It is a comma separated string of
473 std::vector<std::string> InstrsForCase;
474 InstrsForCase.resize(UniqueOperandCommands.size());
475 InstOpsUsed.assign(UniqueOperandCommands.size(), 0);
477 for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
478 const AsmWriterInst *Inst = getAsmWriterInstByID(i);
479 if (Inst == 0) continue; // PHI, INLINEASM, DBG_LABEL, etc.
482 if (Inst->Operands.empty())
483 continue; // Instruction already done.
485 Command = " " + Inst->Operands[0].getCode() + "\n";
487 // If this is the last operand, emit a return.
488 if (Inst->Operands.size() == 1) {
489 Command += " EmitComments(*MI);\n";
490 // Print the final newline
491 Command += " O << \"\\n\";\n";
492 Command += " return true;\n";
495 // Check to see if we already have 'Command' in UniqueOperandCommands.
497 bool FoundIt = false;
498 for (unsigned idx = 0, e = UniqueOperandCommands.size(); idx != e; ++idx)
499 if (UniqueOperandCommands[idx] == Command) {
501 InstrsForCase[idx] += ", ";
502 InstrsForCase[idx] += Inst->CGI->TheDef->getName();
507 InstIdxs[i] = UniqueOperandCommands.size();
508 UniqueOperandCommands.push_back(Command);
509 InstrsForCase.push_back(Inst->CGI->TheDef->getName());
511 // This command matches one operand so far.
512 InstOpsUsed.push_back(1);
516 // For each entry of UniqueOperandCommands, there is a set of instructions
517 // that uses it. If the next command of all instructions in the set are
518 // identical, fold it into the command.
519 for (unsigned CommandIdx = 0, e = UniqueOperandCommands.size();
520 CommandIdx != e; ++CommandIdx) {
522 for (unsigned Op = 1; ; ++Op) {
523 // Scan for the first instruction in the set.
524 std::vector<unsigned>::iterator NIT =
525 std::find(InstIdxs.begin(), InstIdxs.end(), CommandIdx);
526 if (NIT == InstIdxs.end()) break; // No commonality.
528 // If this instruction has no more operands, we isn't anything to merge
529 // into this command.
530 const AsmWriterInst *FirstInst =
531 getAsmWriterInstByID(NIT-InstIdxs.begin());
532 if (!FirstInst || FirstInst->Operands.size() == Op)
535 // Otherwise, scan to see if all of the other instructions in this command
536 // set share the operand.
539 for (NIT = std::find(NIT+1, InstIdxs.end(), CommandIdx);
540 NIT != InstIdxs.end();
541 NIT = std::find(NIT+1, InstIdxs.end(), CommandIdx)) {
542 // Okay, found another instruction in this command set. If the operand
543 // matches, we're ok, otherwise bail out.
544 const AsmWriterInst *OtherInst =
545 getAsmWriterInstByID(NIT-InstIdxs.begin());
546 if (!OtherInst || OtherInst->Operands.size() == Op ||
547 OtherInst->Operands[Op] != FirstInst->Operands[Op]) {
554 // Okay, everything in this command set has the same next operand. Add it
555 // to UniqueOperandCommands and remember that it was consumed.
556 std::string Command = " " + FirstInst->Operands[Op].getCode() + "\n";
558 // If this is the last operand, emit a return after the code.
559 if (FirstInst->Operands.size() == Op+1) {
560 Command += " EmitComments(*MI);\n";
561 // Print the final newline
562 Command += " O << \"\\n\";\n";
563 Command += " return true;\n";
566 UniqueOperandCommands[CommandIdx] += Command;
567 InstOpsUsed[CommandIdx]++;
571 // Prepend some of the instructions each case is used for onto the case val.
572 for (unsigned i = 0, e = InstrsForCase.size(); i != e; ++i) {
573 std::string Instrs = InstrsForCase[i];
574 if (Instrs.size() > 70) {
575 Instrs.erase(Instrs.begin()+70, Instrs.end());
580 UniqueOperandCommands[i] = " // " + Instrs + "\n" +
581 UniqueOperandCommands[i];
587 void AsmWriterEmitter::run(raw_ostream &O) {
588 EmitSourceFileHeader("Assembly Writer Source Fragment", O);
590 CodeGenTarget Target;
591 Record *AsmWriter = Target.getAsmWriter();
592 std::string ClassName = AsmWriter->getValueAsString("AsmWriterClassName");
593 unsigned Variant = AsmWriter->getValueAsInt("Variant");
596 "/// printInstruction - This method is automatically generated by tablegen\n"
597 "/// from the instruction set description. This method returns true if the\n"
598 "/// machine instruction was sufficiently described to print it, otherwise\n"
599 "/// it returns false.\n"
600 "bool " << Target.getName() << ClassName
601 << "::printInstruction(const MachineInstr *MI) {\n";
603 std::vector<AsmWriterInst> Instructions;
605 for (CodeGenTarget::inst_iterator I = Target.inst_begin(),
606 E = Target.inst_end(); I != E; ++I)
607 if (!I->second.AsmString.empty())
608 Instructions.push_back(AsmWriterInst(I->second, Variant));
610 // Get the instruction numbering.
611 Target.getInstructionsByEnumValue(NumberedInstructions);
613 // Compute the CodeGenInstruction -> AsmWriterInst mapping. Note that not
614 // all machine instructions are necessarily being printed, so there may be
615 // target instructions not in this map.
616 for (unsigned i = 0, e = Instructions.size(); i != e; ++i)
617 CGIAWIMap.insert(std::make_pair(Instructions[i].CGI, &Instructions[i]));
619 // Build an aggregate string, and build a table of offsets into it.
620 std::map<std::string, unsigned> StringOffset;
621 std::string AggregateString;
622 AggregateString.push_back(0); // "\0"
623 AggregateString.push_back(0); // "\0"
625 /// OpcodeInfo - This encodes the index of the string to use for the first
626 /// chunk of the output as well as indices used for operand printing.
627 std::vector<unsigned> OpcodeInfo;
629 unsigned MaxStringIdx = 0;
630 for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
631 AsmWriterInst *AWI = CGIAWIMap[NumberedInstructions[i]];
634 // Something not handled by the asmwriter printer.
636 } else if (AWI->Operands[0].OperandType !=
637 AsmWriterOperand::isLiteralTextOperand ||
638 AWI->Operands[0].Str.empty()) {
639 // Something handled by the asmwriter printer, but with no leading string.
642 unsigned &Entry = StringOffset[AWI->Operands[0].Str];
644 // Add the string to the aggregate if this is the first time found.
645 MaxStringIdx = Entry = AggregateString.size();
646 std::string Str = AWI->Operands[0].Str;
648 AggregateString += Str;
649 AggregateString += '\0';
653 // Nuke the string from the operand list. It is now handled!
654 AWI->Operands.erase(AWI->Operands.begin());
656 OpcodeInfo.push_back(Idx);
659 // Figure out how many bits we used for the string index.
660 unsigned AsmStrBits = Log2_32_Ceil(MaxStringIdx+1);
662 // To reduce code size, we compactify common instructions into a few bits
663 // in the opcode-indexed table.
664 unsigned BitsLeft = 32-AsmStrBits;
666 std::vector<std::vector<std::string> > TableDrivenOperandPrinters;
670 std::vector<std::string> UniqueOperandCommands;
672 // For the first operand check, add a default value for instructions with
673 // just opcode strings to use.
675 // Do the post instruction processing and print the final newline
676 UniqueOperandCommands.push_back(" EmitComments(*MI);\n O << \"\\n\";\n return true;\n");
680 std::vector<unsigned> InstIdxs;
681 std::vector<unsigned> NumInstOpsHandled;
682 FindUniqueOperandCommands(UniqueOperandCommands, InstIdxs,
685 // If we ran out of operands to print, we're done.
686 if (UniqueOperandCommands.empty()) break;
688 // Compute the number of bits we need to represent these cases, this is
689 // ceil(log2(numentries)).
690 unsigned NumBits = Log2_32_Ceil(UniqueOperandCommands.size());
692 // If we don't have enough bits for this operand, don't include it.
693 if (NumBits > BitsLeft) {
694 DOUT << "Not enough bits to densely encode " << NumBits
699 // Otherwise, we can include this in the initial lookup table. Add it in.
701 for (unsigned i = 0, e = InstIdxs.size(); i != e; ++i)
702 if (InstIdxs[i] != ~0U)
703 OpcodeInfo[i] |= InstIdxs[i] << (BitsLeft+AsmStrBits);
705 // Remove the info about this operand.
706 for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
707 if (AsmWriterInst *Inst = getAsmWriterInstByID(i))
708 if (!Inst->Operands.empty()) {
709 unsigned NumOps = NumInstOpsHandled[InstIdxs[i]];
710 assert(NumOps <= Inst->Operands.size() &&
711 "Can't remove this many ops!");
712 Inst->Operands.erase(Inst->Operands.begin(),
713 Inst->Operands.begin()+NumOps);
717 // Remember the handlers for this set of operands.
718 TableDrivenOperandPrinters.push_back(UniqueOperandCommands);
723 O<<" static const unsigned OpInfo[] = {\n";
724 for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
725 O << " " << OpcodeInfo[i] << "U,\t// "
726 << NumberedInstructions[i]->TheDef->getName() << "\n";
728 // Add a dummy entry so the array init doesn't end with a comma.
732 // Emit the string itself.
733 O << " const char *AsmStrs = \n \"";
734 unsigned CharsPrinted = 0;
735 EscapeString(AggregateString);
736 for (unsigned i = 0, e = AggregateString.size(); i != e; ++i) {
737 if (CharsPrinted > 70) {
741 O << AggregateString[i];
744 // Print escape sequences all together.
745 if (AggregateString[i] == '\\') {
746 assert(i+1 < AggregateString.size() && "Incomplete escape sequence!");
747 if (isdigit(AggregateString[i+1])) {
748 assert(isdigit(AggregateString[i+2]) && isdigit(AggregateString[i+3]) &&
749 "Expected 3 digit octal escape!");
750 O << AggregateString[++i];
751 O << AggregateString[++i];
752 O << AggregateString[++i];
755 O << AggregateString[++i];
762 O << " processDebugLoc(MI->getDebugLoc());\n\n";
764 O << "\n#ifndef NO_ASM_WRITER_BOILERPLATE\n";
766 O << " if (MI->getOpcode() == TargetInstrInfo::INLINEASM) {\n"
767 << " O << \"\\t\";\n"
768 << " printInlineAsm(MI);\n"
770 << " } else if (MI->isLabel()) {\n"
771 << " printLabel(MI);\n"
773 << " } else if (MI->getOpcode() == TargetInstrInfo::DECLARE) {\n"
774 << " printDeclare(MI);\n"
776 << " } else if (MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF) {\n"
777 << " printImplicitDef(MI);\n"
783 O << " O << \"\\t\";\n\n";
785 O << " // Emit the opcode for the instruction.\n"
786 << " unsigned Bits = OpInfo[MI->getOpcode()];\n"
787 << " if (Bits == 0) return false;\n\n";
789 O << " std::string OpStr(AsmStrs+(Bits & " << (1 << AsmStrBits)-1 << "));\n"
790 << " unsigned OperandColumn = 1;\n"
791 << " O << OpStr;\n\n";
793 O << " if (OpStr.find_last_of(\" \\t\") == OpStr.size()-1) {\n"
794 << " O.PadToColumn(TAI->getOperandColumn(1));\n"
795 << " OperandColumn = 2;\n"
798 // Output the table driven operand information.
799 BitsLeft = 32-AsmStrBits;
800 for (unsigned i = 0, e = TableDrivenOperandPrinters.size(); i != e; ++i) {
801 std::vector<std::string> &Commands = TableDrivenOperandPrinters[i];
803 // Compute the number of bits we need to represent these cases, this is
804 // ceil(log2(numentries)).
805 unsigned NumBits = Log2_32_Ceil(Commands.size());
806 assert(NumBits <= BitsLeft && "consistency error");
808 // Emit code to extract this field from Bits.
811 O << "\n // Fragment " << i << " encoded into " << NumBits
812 << " bits for " << Commands.size() << " unique commands.\n";
814 if (Commands.size() == 2) {
815 // Emit two possibilitys with if/else.
816 O << " if ((Bits >> " << (BitsLeft+AsmStrBits) << ") & "
817 << ((1 << NumBits)-1) << ") {\n"
823 O << " switch ((Bits >> " << (BitsLeft+AsmStrBits) << ") & "
824 << ((1 << NumBits)-1) << ") {\n"
825 << " default: // unreachable.\n";
827 // Print out all the cases.
828 for (unsigned i = 0, e = Commands.size(); i != e; ++i) {
829 O << " case " << i << ":\n";
837 // Okay, delete instructions with no operand info left.
838 for (unsigned i = 0, e = Instructions.size(); i != e; ++i) {
839 // Entire instruction has been emitted?
840 AsmWriterInst &Inst = Instructions[i];
841 if (Inst.Operands.empty()) {
842 Instructions.erase(Instructions.begin()+i);
848 // Because this is a vector, we want to emit from the end. Reverse all of the
849 // elements in the vector.
850 std::reverse(Instructions.begin(), Instructions.end());
852 if (!Instructions.empty()) {
853 // Find the opcode # of inline asm.
854 O << " switch (MI->getOpcode()) {\n";
855 while (!Instructions.empty())
856 EmitInstructions(Instructions, O);
859 O << " EmitComments(*MI);\n";
861 // Print the final newline
862 O << " O << \"\\n\";\n";
863 O << " return true;\n";