CodeGenInstruction.cpp revision d568b3f55294917d1cc701da14a8a7daeb6563e6 
1//===- CodeGenInstruction.cpp - CodeGen Instruction Class Wrapper ---------===//
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 implements the CodeGenInstruction class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "CodeGenInstruction.h"
15#include "CodeGenTarget.h"
16#include "Error.h"
17#include "Record.h"
18#include "llvm/ADT/StringExtras.h"
19#include "llvm/ADT/StringMap.h"
20#include "llvm/ADT/STLExtras.h"
21#include <set>
22using namespace llvm;
23
24//===----------------------------------------------------------------------===//
25// CGIOperandList Implementation
26//===----------------------------------------------------------------------===//
27
28CGIOperandList::CGIOperandList(Record *R) : TheDef(R) {
29  isPredicable = false;
30  hasOptionalDef = false;
31  isVariadic = false;
32
33  DagInit *OutDI = R->getValueAsDag("OutOperandList");
34
35  if (DefInit *Init = dynamic_cast<DefInit*>(OutDI->getOperator())) {
36    if (Init->getDef()->getName() != "outs")
37      throw R->getName() + ": invalid def name for output list: use 'outs'";
38  } else
39    throw R->getName() + ": invalid output list: use 'outs'";
40
41  NumDefs = OutDI->getNumArgs();
42
43  DagInit *InDI = R->getValueAsDag("InOperandList");
44  if (DefInit *Init = dynamic_cast<DefInit*>(InDI->getOperator())) {
45    if (Init->getDef()->getName() != "ins")
46      throw R->getName() + ": invalid def name for input list: use 'ins'";
47  } else
48    throw R->getName() + ": invalid input list: use 'ins'";
49
50  unsigned MIOperandNo = 0;
51  std::set<std::string> OperandNames;
52  for (unsigned i = 0, e = InDI->getNumArgs()+OutDI->getNumArgs(); i != e; ++i){
53    Init *ArgInit;
54    std::string ArgName;
55    if (i < NumDefs) {
56      ArgInit = OutDI->getArg(i);
57      ArgName = OutDI->getArgName(i);
58    } else {
59      ArgInit = InDI->getArg(i-NumDefs);
60      ArgName = InDI->getArgName(i-NumDefs);
61    }
62
63    DefInit *Arg = dynamic_cast<DefInit*>(ArgInit);
64    if (!Arg)
65      throw "Illegal operand for the '" + R->getName() + "' instruction!";
66
67    Record *Rec = Arg->getDef();
68    std::string PrintMethod = "printOperand";
69    std::string EncoderMethod;
70    unsigned NumOps = 1;
71    DagInit *MIOpInfo = 0;
72    if (Rec->isSubClassOf("RegisterOperand")) {
73      PrintMethod = Rec->getValueAsString("PrintMethod");
74    } else if (Rec->isSubClassOf("Operand")) {
75      PrintMethod = Rec->getValueAsString("PrintMethod");
76      // If there is an explicit encoder method, use it.
77      EncoderMethod = Rec->getValueAsString("EncoderMethod");
78      MIOpInfo = Rec->getValueAsDag("MIOperandInfo");
79
80      // Verify that MIOpInfo has an 'ops' root value.
81      if (!dynamic_cast<DefInit*>(MIOpInfo->getOperator()) ||
82          dynamic_cast<DefInit*>(MIOpInfo->getOperator())
83          ->getDef()->getName() != "ops")
84        throw "Bad value for MIOperandInfo in operand '" + Rec->getName() +
85        "'\n";
86
87      // If we have MIOpInfo, then we have #operands equal to number of entries
88      // in MIOperandInfo.
89      if (unsigned NumArgs = MIOpInfo->getNumArgs())
90        NumOps = NumArgs;
91
92      if (Rec->isSubClassOf("PredicateOperand"))
93        isPredicable = true;
94      else if (Rec->isSubClassOf("OptionalDefOperand"))
95        hasOptionalDef = true;
96    } else if (Rec->getName() == "variable_ops") {
97      isVariadic = true;
98      continue;
99    } else if (!Rec->isSubClassOf("RegisterClass") &&
100               !Rec->isSubClassOf("PointerLikeRegClass") &&
101               Rec->getName() != "unknown")
102      throw "Unknown operand class '" + Rec->getName() +
103      "' in '" + R->getName() + "' instruction!";
104
105    // Check that the operand has a name and that it's unique.
106    if (ArgName.empty())
107      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
108      " has no name!";
109    if (!OperandNames.insert(ArgName).second)
110      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
111      " has the same name as a previous operand!";
112
113    OperandList.push_back(OperandInfo(Rec, ArgName, PrintMethod, EncoderMethod,
114                                      MIOperandNo, NumOps, MIOpInfo));
115    MIOperandNo += NumOps;
116  }
117
118
119  // Make sure the constraints list for each operand is large enough to hold
120  // constraint info, even if none is present.
121  for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
122    OperandList[i].Constraints.resize(OperandList[i].MINumOperands);
123}
124
125
126/// getOperandNamed - Return the index of the operand with the specified
127/// non-empty name.  If the instruction does not have an operand with the
128/// specified name, throw an exception.
129///
130unsigned CGIOperandList::getOperandNamed(StringRef Name) const {
131  unsigned OpIdx;
132  if (hasOperandNamed(Name, OpIdx)) return OpIdx;
133  throw "'" + TheDef->getName() + "' does not have an operand named '$" +
134    Name.str() + "'!";
135}
136
137/// hasOperandNamed - Query whether the instruction has an operand of the
138/// given name. If so, return true and set OpIdx to the index of the
139/// operand. Otherwise, return false.
140bool CGIOperandList::hasOperandNamed(StringRef Name, unsigned &OpIdx) const {
141  assert(!Name.empty() && "Cannot search for operand with no name!");
142  for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
143    if (OperandList[i].Name == Name) {
144      OpIdx = i;
145      return true;
146    }
147  return false;
148}
149
150std::pair<unsigned,unsigned>
151CGIOperandList::ParseOperandName(const std::string &Op, bool AllowWholeOp) {
152  if (Op.empty() || Op[0] != '$')
153    throw TheDef->getName() + ": Illegal operand name: '" + Op + "'";
154
155  std::string OpName = Op.substr(1);
156  std::string SubOpName;
157
158  // Check to see if this is $foo.bar.
159  std::string::size_type DotIdx = OpName.find_first_of(".");
160  if (DotIdx != std::string::npos) {
161    SubOpName = OpName.substr(DotIdx+1);
162    if (SubOpName.empty())
163      throw TheDef->getName() + ": illegal empty suboperand name in '" +Op +"'";
164    OpName = OpName.substr(0, DotIdx);
165  }
166
167  unsigned OpIdx = getOperandNamed(OpName);
168
169  if (SubOpName.empty()) {  // If no suboperand name was specified:
170    // If one was needed, throw.
171    if (OperandList[OpIdx].MINumOperands > 1 && !AllowWholeOp &&
172        SubOpName.empty())
173      throw TheDef->getName() + ": Illegal to refer to"
174      " whole operand part of complex operand '" + Op + "'";
175
176    // Otherwise, return the operand.
177    return std::make_pair(OpIdx, 0U);
178  }
179
180  // Find the suboperand number involved.
181  DagInit *MIOpInfo = OperandList[OpIdx].MIOperandInfo;
182  if (MIOpInfo == 0)
183    throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
184
185  // Find the operand with the right name.
186  for (unsigned i = 0, e = MIOpInfo->getNumArgs(); i != e; ++i)
187    if (MIOpInfo->getArgName(i) == SubOpName)
188      return std::make_pair(OpIdx, i);
189
190  // Otherwise, didn't find it!
191  throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
192}
193
194static void ParseConstraint(const std::string &CStr, CGIOperandList &Ops) {
195  // EARLY_CLOBBER: @early $reg
196  std::string::size_type wpos = CStr.find_first_of(" \t");
197  std::string::size_type start = CStr.find_first_not_of(" \t");
198  std::string Tok = CStr.substr(start, wpos - start);
199  if (Tok == "@earlyclobber") {
200    std::string Name = CStr.substr(wpos+1);
201    wpos = Name.find_first_not_of(" \t");
202    if (wpos == std::string::npos)
203      throw "Illegal format for @earlyclobber constraint: '" + CStr + "'";
204    Name = Name.substr(wpos);
205    std::pair<unsigned,unsigned> Op = Ops.ParseOperandName(Name, false);
206
207    // Build the string for the operand
208    if (!Ops[Op.first].Constraints[Op.second].isNone())
209      throw "Operand '" + Name + "' cannot have multiple constraints!";
210    Ops[Op.first].Constraints[Op.second] =
211    CGIOperandList::ConstraintInfo::getEarlyClobber();
212    return;
213  }
214
215  // Only other constraint is "TIED_TO" for now.
216  std::string::size_type pos = CStr.find_first_of('=');
217  assert(pos != std::string::npos && "Unrecognized constraint");
218  start = CStr.find_first_not_of(" \t");
219  std::string Name = CStr.substr(start, pos - start);
220
221  // TIED_TO: $src1 = $dst
222  wpos = Name.find_first_of(" \t");
223  if (wpos == std::string::npos)
224    throw "Illegal format for tied-to constraint: '" + CStr + "'";
225  std::string DestOpName = Name.substr(0, wpos);
226  std::pair<unsigned,unsigned> DestOp = Ops.ParseOperandName(DestOpName, false);
227
228  Name = CStr.substr(pos+1);
229  wpos = Name.find_first_not_of(" \t");
230  if (wpos == std::string::npos)
231    throw "Illegal format for tied-to constraint: '" + CStr + "'";
232
233  std::pair<unsigned,unsigned> SrcOp =
234  Ops.ParseOperandName(Name.substr(wpos), false);
235  if (SrcOp > DestOp)
236    throw "Illegal tied-to operand constraint '" + CStr + "'";
237
238
239  unsigned FlatOpNo = Ops.getFlattenedOperandNumber(SrcOp);
240
241  if (!Ops[DestOp.first].Constraints[DestOp.second].isNone())
242    throw "Operand '" + DestOpName + "' cannot have multiple constraints!";
243  Ops[DestOp.first].Constraints[DestOp.second] =
244  CGIOperandList::ConstraintInfo::getTied(FlatOpNo);
245}
246
247static void ParseConstraints(const std::string &CStr, CGIOperandList &Ops) {
248  if (CStr.empty()) return;
249
250  const std::string delims(",");
251  std::string::size_type bidx, eidx;
252
253  bidx = CStr.find_first_not_of(delims);
254  while (bidx != std::string::npos) {
255    eidx = CStr.find_first_of(delims, bidx);
256    if (eidx == std::string::npos)
257      eidx = CStr.length();
258
259    ParseConstraint(CStr.substr(bidx, eidx - bidx), Ops);
260    bidx = CStr.find_first_not_of(delims, eidx);
261  }
262}
263
264void CGIOperandList::ProcessDisableEncoding(std::string DisableEncoding) {
265  while (1) {
266    std::string OpName;
267    tie(OpName, DisableEncoding) = getToken(DisableEncoding, " ,\t");
268    if (OpName.empty()) break;
269
270    // Figure out which operand this is.
271    std::pair<unsigned,unsigned> Op = ParseOperandName(OpName, false);
272
273    // Mark the operand as not-to-be encoded.
274    if (Op.second >= OperandList[Op.first].DoNotEncode.size())
275      OperandList[Op.first].DoNotEncode.resize(Op.second+1);
276    OperandList[Op.first].DoNotEncode[Op.second] = true;
277  }
278
279}
280
281//===----------------------------------------------------------------------===//
282// CodeGenInstruction Implementation
283//===----------------------------------------------------------------------===//
284
285CodeGenInstruction::CodeGenInstruction(Record *R) : TheDef(R), Operands(R) {
286  Namespace = R->getValueAsString("Namespace");
287  AsmString = R->getValueAsString("AsmString");
288
289  isReturn     = R->getValueAsBit("isReturn");
290  isBranch     = R->getValueAsBit("isBranch");
291  isIndirectBranch = R->getValueAsBit("isIndirectBranch");
292  isCompare    = R->getValueAsBit("isCompare");
293  isMoveImm    = R->getValueAsBit("isMoveImm");
294  isBitcast    = R->getValueAsBit("isBitcast");
295  isBarrier    = R->getValueAsBit("isBarrier");
296  isCall       = R->getValueAsBit("isCall");
297  canFoldAsLoad = R->getValueAsBit("canFoldAsLoad");
298  mayLoad      = R->getValueAsBit("mayLoad");
299  mayStore     = R->getValueAsBit("mayStore");
300  isPredicable = Operands.isPredicable || R->getValueAsBit("isPredicable");
301  isConvertibleToThreeAddress = R->getValueAsBit("isConvertibleToThreeAddress");
302  isCommutable = R->getValueAsBit("isCommutable");
303  isTerminator = R->getValueAsBit("isTerminator");
304  isReMaterializable = R->getValueAsBit("isReMaterializable");
305  hasDelaySlot = R->getValueAsBit("hasDelaySlot");
306  usesCustomInserter = R->getValueAsBit("usesCustomInserter");
307  hasCtrlDep   = R->getValueAsBit("hasCtrlDep");
308  isNotDuplicable = R->getValueAsBit("isNotDuplicable");
309  hasSideEffects = R->getValueAsBit("hasSideEffects");
310  neverHasSideEffects = R->getValueAsBit("neverHasSideEffects");
311  isAsCheapAsAMove = R->getValueAsBit("isAsCheapAsAMove");
312  hasExtraSrcRegAllocReq = R->getValueAsBit("hasExtraSrcRegAllocReq");
313  hasExtraDefRegAllocReq = R->getValueAsBit("hasExtraDefRegAllocReq");
314  isCodeGenOnly = R->getValueAsBit("isCodeGenOnly");
315  isPseudo = R->getValueAsBit("isPseudo");
316  ImplicitDefs = R->getValueAsListOfDefs("Defs");
317  ImplicitUses = R->getValueAsListOfDefs("Uses");
318
319  if (neverHasSideEffects + hasSideEffects > 1)
320    throw R->getName() + ": multiple conflicting side-effect flags set!";
321
322  // Parse Constraints.
323  ParseConstraints(R->getValueAsString("Constraints"), Operands);
324
325  // Parse the DisableEncoding field.
326  Operands.ProcessDisableEncoding(R->getValueAsString("DisableEncoding"));
327}
328
329/// HasOneImplicitDefWithKnownVT - If the instruction has at least one
330/// implicit def and it has a known VT, return the VT, otherwise return
331/// MVT::Other.
332MVT::SimpleValueType CodeGenInstruction::
333HasOneImplicitDefWithKnownVT(const CodeGenTarget &TargetInfo) const {
334  if (ImplicitDefs.empty()) return MVT::Other;
335
336  // Check to see if the first implicit def has a resolvable type.
337  Record *FirstImplicitDef = ImplicitDefs[0];
338  assert(FirstImplicitDef->isSubClassOf("Register"));
339  const std::vector<MVT::SimpleValueType> &RegVTs =
340    TargetInfo.getRegisterVTs(FirstImplicitDef);
341  if (RegVTs.size() == 1)
342    return RegVTs[0];
343  return MVT::Other;
344}
345
346
347/// FlattenAsmStringVariants - Flatten the specified AsmString to only
348/// include text from the specified variant, returning the new string.
349std::string CodeGenInstruction::
350FlattenAsmStringVariants(StringRef Cur, unsigned Variant) {
351  std::string Res = "";
352
353  for (;;) {
354    // Find the start of the next variant string.
355    size_t VariantsStart = 0;
356    for (size_t e = Cur.size(); VariantsStart != e; ++VariantsStart)
357      if (Cur[VariantsStart] == '{' &&
358          (VariantsStart == 0 || (Cur[VariantsStart-1] != '$' &&
359                                  Cur[VariantsStart-1] != '\\')))
360        break;
361
362    // Add the prefix to the result.
363    Res += Cur.slice(0, VariantsStart);
364    if (VariantsStart == Cur.size())
365      break;
366
367    ++VariantsStart; // Skip the '{'.
368
369    // Scan to the end of the variants string.
370    size_t VariantsEnd = VariantsStart;
371    unsigned NestedBraces = 1;
372    for (size_t e = Cur.size(); VariantsEnd != e; ++VariantsEnd) {
373      if (Cur[VariantsEnd] == '}' && Cur[VariantsEnd-1] != '\\') {
374        if (--NestedBraces == 0)
375          break;
376      } else if (Cur[VariantsEnd] == '{')
377        ++NestedBraces;
378    }
379
380    // Select the Nth variant (or empty).
381    StringRef Selection = Cur.slice(VariantsStart, VariantsEnd);
382    for (unsigned i = 0; i != Variant; ++i)
383      Selection = Selection.split('|').second;
384    Res += Selection.split('|').first;
385
386    assert(VariantsEnd != Cur.size() &&
387           "Unterminated variants in assembly string!");
388    Cur = Cur.substr(VariantsEnd + 1);
389  }
390
391  return Res;
392}
393
394
395//===----------------------------------------------------------------------===//
396/// CodeGenInstAlias Implementation
397//===----------------------------------------------------------------------===//
398
399/// tryAliasOpMatch - This is a helper function for the CodeGenInstAlias
400/// constructor.  It checks if an argument in an InstAlias pattern matches
401/// the corresponding operand of the instruction.  It returns true on a
402/// successful match, with ResOp set to the result operand to be used.
403bool CodeGenInstAlias::tryAliasOpMatch(DagInit *Result, unsigned AliasOpNo,
404                                       Record *InstOpRec, bool hasSubOps,
405                                       SMLoc Loc, CodeGenTarget &T,
406                                       ResultOperand &ResOp) {
407  Init *Arg = Result->getArg(AliasOpNo);
408  DefInit *ADI = dynamic_cast<DefInit*>(Arg);
409
410  if (ADI && ADI->getDef() == InstOpRec) {
411    // If the operand is a record, it must have a name, and the record type
412    // must match up with the instruction's argument type.
413    if (Result->getArgName(AliasOpNo).empty())
414      throw TGError(Loc, "result argument #" + utostr(AliasOpNo) +
415                    " must have a name!");
416    ResOp = ResultOperand(Result->getArgName(AliasOpNo), ADI->getDef());
417    return true;
418  }
419
420  // Handle explicit registers.
421  if (ADI && ADI->getDef()->isSubClassOf("Register")) {
422    if (InstOpRec->isSubClassOf("RegisterOperand"))
423      InstOpRec = InstOpRec->getValueAsDef("RegClass");
424
425    if (!InstOpRec->isSubClassOf("RegisterClass"))
426      return false;
427
428    if (!T.getRegisterClass(InstOpRec)
429        .contains(T.getRegBank().getReg(ADI->getDef())))
430      throw TGError(Loc, "fixed register " +ADI->getDef()->getName()
431                    + " is not a member of the " + InstOpRec->getName() +
432                    " register class!");
433
434    if (!Result->getArgName(AliasOpNo).empty())
435      throw TGError(Loc, "result fixed register argument must "
436                    "not have a name!");
437
438    ResOp = ResultOperand(ADI->getDef());
439    return true;
440  }
441
442  // Handle "zero_reg" for optional def operands.
443  if (ADI && ADI->getDef()->getName() == "zero_reg") {
444
445    // Check if this is an optional def.
446    if (!InstOpRec->isSubClassOf("OptionalDefOperand"))
447      throw TGError(Loc, "reg0 used for result that is not an "
448                    "OptionalDefOperand!");
449
450    ResOp = ResultOperand(static_cast<Record*>(0));
451    return true;
452  }
453
454  if (IntInit *II = dynamic_cast<IntInit*>(Arg)) {
455    if (hasSubOps || !InstOpRec->isSubClassOf("Operand"))
456      return false;
457    // Integer arguments can't have names.
458    if (!Result->getArgName(AliasOpNo).empty())
459      throw TGError(Loc, "result argument #" + utostr(AliasOpNo) +
460                    " must not have a name!");
461    ResOp = ResultOperand(II->getValue());
462    return true;
463  }
464
465  return false;
466}
467
468CodeGenInstAlias::CodeGenInstAlias(Record *R, CodeGenTarget &T) : TheDef(R) {
469  AsmString = R->getValueAsString("AsmString");
470  Result = R->getValueAsDag("ResultInst");
471
472  // Verify that the root of the result is an instruction.
473  DefInit *DI = dynamic_cast<DefInit*>(Result->getOperator());
474  if (DI == 0 || !DI->getDef()->isSubClassOf("Instruction"))
475    throw TGError(R->getLoc(), "result of inst alias should be an instruction");
476
477  ResultInst = &T.getInstruction(DI->getDef());
478
479  // NameClass - If argument names are repeated, we need to verify they have
480  // the same class.
481  StringMap<Record*> NameClass;
482  for (unsigned i = 0, e = Result->getNumArgs(); i != e; ++i) {
483    DefInit *ADI = dynamic_cast<DefInit*>(Result->getArg(i));
484    if (!ADI || Result->getArgName(i).empty())
485      continue;
486    // Verify we don't have something like: (someinst GR16:$foo, GR32:$foo)
487    // $foo can exist multiple times in the result list, but it must have the
488    // same type.
489    Record *&Entry = NameClass[Result->getArgName(i)];
490    if (Entry && Entry != ADI->getDef())
491      throw TGError(R->getLoc(), "result value $" + Result->getArgName(i) +
492                    " is both " + Entry->getName() + " and " +
493                    ADI->getDef()->getName() + "!");
494    Entry = ADI->getDef();
495  }
496
497  // Decode and validate the arguments of the result.
498  unsigned AliasOpNo = 0;
499  for (unsigned i = 0, e = ResultInst->Operands.size(); i != e; ++i) {
500
501    // Tied registers don't have an entry in the result dag.
502    if (ResultInst->Operands[i].getTiedRegister() != -1)
503      continue;
504
505    if (AliasOpNo >= Result->getNumArgs())
506      throw TGError(R->getLoc(), "not enough arguments for instruction!");
507
508    Record *InstOpRec = ResultInst->Operands[i].Rec;
509    unsigned NumSubOps = ResultInst->Operands[i].MINumOperands;
510    ResultOperand ResOp(static_cast<int64_t>(0));
511    if (tryAliasOpMatch(Result, AliasOpNo, InstOpRec, (NumSubOps > 1),
512                        R->getLoc(), T, ResOp)) {
513      ResultOperands.push_back(ResOp);
514      ResultInstOperandIndex.push_back(std::make_pair(i, -1));
515      ++AliasOpNo;
516      continue;
517    }
518
519    // If the argument did not match the instruction operand, and the operand
520    // is composed of multiple suboperands, try matching the suboperands.
521    if (NumSubOps > 1) {
522      DagInit *MIOI = ResultInst->Operands[i].MIOperandInfo;
523      for (unsigned SubOp = 0; SubOp != NumSubOps; ++SubOp) {
524        if (AliasOpNo >= Result->getNumArgs())
525          throw TGError(R->getLoc(), "not enough arguments for instruction!");
526        Record *SubRec = dynamic_cast<DefInit*>(MIOI->getArg(SubOp))->getDef();
527        if (tryAliasOpMatch(Result, AliasOpNo, SubRec, false,
528                            R->getLoc(), T, ResOp)) {
529          ResultOperands.push_back(ResOp);
530          ResultInstOperandIndex.push_back(std::make_pair(i, SubOp));
531          ++AliasOpNo;
532        } else {
533          throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
534                        " does not match instruction operand class " +
535                        (SubOp == 0 ? InstOpRec->getName() :SubRec->getName()));
536        }
537      }
538      continue;
539    }
540    throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
541                  " does not match instruction operand class " +
542                  InstOpRec->getName());
543  }
544
545  if (AliasOpNo != Result->getNumArgs())
546    throw TGError(R->getLoc(), "too many operands for instruction!");
547}
548