CodeGenInstruction.cpp revision 2ac190238e88b21e716e2853900b5076c9013410 
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 "Record.h"
17#include "llvm/ADT/StringExtras.h"
18#include "llvm/ADT/StringMap.h"
19#include "llvm/ADT/STLExtras.h"
20#include <set>
21using namespace llvm;
22
23//===----------------------------------------------------------------------===//
24// CGIOperandList Implementation
25//===----------------------------------------------------------------------===//
26
27CGIOperandList::CGIOperandList(Record *R) : TheDef(R) {
28  isPredicable = false;
29  hasOptionalDef = false;
30  isVariadic = false;
31
32  DagInit *OutDI = R->getValueAsDag("OutOperandList");
33
34  if (DefInit *Init = dynamic_cast<DefInit*>(OutDI->getOperator())) {
35    if (Init->getDef()->getName() != "outs")
36      throw R->getName() + ": invalid def name for output list: use 'outs'";
37  } else
38    throw R->getName() + ": invalid output list: use 'outs'";
39
40  NumDefs = OutDI->getNumArgs();
41
42  DagInit *InDI = R->getValueAsDag("InOperandList");
43  if (DefInit *Init = dynamic_cast<DefInit*>(InDI->getOperator())) {
44    if (Init->getDef()->getName() != "ins")
45      throw R->getName() + ": invalid def name for input list: use 'ins'";
46  } else
47    throw R->getName() + ": invalid input list: use 'ins'";
48
49  unsigned MIOperandNo = 0;
50  std::set<std::string> OperandNames;
51  for (unsigned i = 0, e = InDI->getNumArgs()+OutDI->getNumArgs(); i != e; ++i){
52    Init *ArgInit;
53    std::string ArgName;
54    if (i < NumDefs) {
55      ArgInit = OutDI->getArg(i);
56      ArgName = OutDI->getArgName(i);
57    } else {
58      ArgInit = InDI->getArg(i-NumDefs);
59      ArgName = InDI->getArgName(i-NumDefs);
60    }
61
62    DefInit *Arg = dynamic_cast<DefInit*>(ArgInit);
63    if (!Arg)
64      throw "Illegal operand for the '" + R->getName() + "' instruction!";
65
66    Record *Rec = Arg->getDef();
67    std::string PrintMethod = "printOperand";
68    std::string EncoderMethod;
69    unsigned NumOps = 1;
70    DagInit *MIOpInfo = 0;
71    if (Rec->isSubClassOf("Operand")) {
72      PrintMethod = Rec->getValueAsString("PrintMethod");
73      // If there is an explicit encoder method, use it.
74      EncoderMethod = Rec->getValueAsString("EncoderMethod");
75      MIOpInfo = Rec->getValueAsDag("MIOperandInfo");
76
77      // Verify that MIOpInfo has an 'ops' root value.
78      if (!dynamic_cast<DefInit*>(MIOpInfo->getOperator()) ||
79          dynamic_cast<DefInit*>(MIOpInfo->getOperator())
80          ->getDef()->getName() != "ops")
81        throw "Bad value for MIOperandInfo in operand '" + Rec->getName() +
82        "'\n";
83
84      // If we have MIOpInfo, then we have #operands equal to number of entries
85      // in MIOperandInfo.
86      if (unsigned NumArgs = MIOpInfo->getNumArgs())
87        NumOps = NumArgs;
88
89      if (Rec->isSubClassOf("PredicateOperand"))
90        isPredicable = true;
91      else if (Rec->isSubClassOf("OptionalDefOperand"))
92        hasOptionalDef = true;
93    } else if (Rec->getName() == "variable_ops") {
94      isVariadic = true;
95      continue;
96    } else if (!Rec->isSubClassOf("RegisterClass") &&
97               Rec->getName() != "ptr_rc" && Rec->getName() != "unknown")
98      throw "Unknown operand class '" + Rec->getName() +
99      "' in '" + R->getName() + "' instruction!";
100
101    // Check that the operand has a name and that it's unique.
102    if (ArgName.empty())
103      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
104      " has no name!";
105    if (!OperandNames.insert(ArgName).second)
106      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
107      " has the same name as a previous operand!";
108
109    OperandList.push_back(OperandInfo(Rec, ArgName, PrintMethod, EncoderMethod,
110                                      MIOperandNo, NumOps, MIOpInfo));
111    MIOperandNo += NumOps;
112  }
113
114
115  // Make sure the constraints list for each operand is large enough to hold
116  // constraint info, even if none is present.
117  for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
118    OperandList[i].Constraints.resize(OperandList[i].MINumOperands);
119}
120
121
122/// getOperandNamed - Return the index of the operand with the specified
123/// non-empty name.  If the instruction does not have an operand with the
124/// specified name, throw an exception.
125///
126unsigned CGIOperandList::getOperandNamed(StringRef Name) const {
127  unsigned OpIdx;
128  if (hasOperandNamed(Name, OpIdx)) return OpIdx;
129  throw "'" + TheDef->getName() + "' does not have an operand named '$" +
130    Name.str() + "'!";
131}
132
133/// hasOperandNamed - Query whether the instruction has an operand of the
134/// given name. If so, return true and set OpIdx to the index of the
135/// operand. Otherwise, return false.
136bool CGIOperandList::hasOperandNamed(StringRef Name, unsigned &OpIdx) const {
137  assert(!Name.empty() && "Cannot search for operand with no name!");
138  for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
139    if (OperandList[i].Name == Name) {
140      OpIdx = i;
141      return true;
142    }
143  return false;
144}
145
146std::pair<unsigned,unsigned>
147CGIOperandList::ParseOperandName(const std::string &Op, bool AllowWholeOp) {
148  if (Op.empty() || Op[0] != '$')
149    throw TheDef->getName() + ": Illegal operand name: '" + Op + "'";
150
151  std::string OpName = Op.substr(1);
152  std::string SubOpName;
153
154  // Check to see if this is $foo.bar.
155  std::string::size_type DotIdx = OpName.find_first_of(".");
156  if (DotIdx != std::string::npos) {
157    SubOpName = OpName.substr(DotIdx+1);
158    if (SubOpName.empty())
159      throw TheDef->getName() + ": illegal empty suboperand name in '" +Op +"'";
160    OpName = OpName.substr(0, DotIdx);
161  }
162
163  unsigned OpIdx = getOperandNamed(OpName);
164
165  if (SubOpName.empty()) {  // If no suboperand name was specified:
166    // If one was needed, throw.
167    if (OperandList[OpIdx].MINumOperands > 1 && !AllowWholeOp &&
168        SubOpName.empty())
169      throw TheDef->getName() + ": Illegal to refer to"
170      " whole operand part of complex operand '" + Op + "'";
171
172    // Otherwise, return the operand.
173    return std::make_pair(OpIdx, 0U);
174  }
175
176  // Find the suboperand number involved.
177  DagInit *MIOpInfo = OperandList[OpIdx].MIOperandInfo;
178  if (MIOpInfo == 0)
179    throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
180
181  // Find the operand with the right name.
182  for (unsigned i = 0, e = MIOpInfo->getNumArgs(); i != e; ++i)
183    if (MIOpInfo->getArgName(i) == SubOpName)
184      return std::make_pair(OpIdx, i);
185
186  // Otherwise, didn't find it!
187  throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
188}
189
190static void ParseConstraint(const std::string &CStr, CGIOperandList &Ops) {
191  // EARLY_CLOBBER: @early $reg
192  std::string::size_type wpos = CStr.find_first_of(" \t");
193  std::string::size_type start = CStr.find_first_not_of(" \t");
194  std::string Tok = CStr.substr(start, wpos - start);
195  if (Tok == "@earlyclobber") {
196    std::string Name = CStr.substr(wpos+1);
197    wpos = Name.find_first_not_of(" \t");
198    if (wpos == std::string::npos)
199      throw "Illegal format for @earlyclobber constraint: '" + CStr + "'";
200    Name = Name.substr(wpos);
201    std::pair<unsigned,unsigned> Op = Ops.ParseOperandName(Name, false);
202
203    // Build the string for the operand
204    if (!Ops[Op.first].Constraints[Op.second].isNone())
205      throw "Operand '" + Name + "' cannot have multiple constraints!";
206    Ops[Op.first].Constraints[Op.second] =
207    CGIOperandList::ConstraintInfo::getEarlyClobber();
208    return;
209  }
210
211  // Only other constraint is "TIED_TO" for now.
212  std::string::size_type pos = CStr.find_first_of('=');
213  assert(pos != std::string::npos && "Unrecognized constraint");
214  start = CStr.find_first_not_of(" \t");
215  std::string Name = CStr.substr(start, pos - start);
216
217  // TIED_TO: $src1 = $dst
218  wpos = Name.find_first_of(" \t");
219  if (wpos == std::string::npos)
220    throw "Illegal format for tied-to constraint: '" + CStr + "'";
221  std::string DestOpName = Name.substr(0, wpos);
222  std::pair<unsigned,unsigned> DestOp = Ops.ParseOperandName(DestOpName, false);
223
224  Name = CStr.substr(pos+1);
225  wpos = Name.find_first_not_of(" \t");
226  if (wpos == std::string::npos)
227    throw "Illegal format for tied-to constraint: '" + CStr + "'";
228
229  std::pair<unsigned,unsigned> SrcOp =
230  Ops.ParseOperandName(Name.substr(wpos), false);
231  if (SrcOp > DestOp)
232    throw "Illegal tied-to operand constraint '" + CStr + "'";
233
234
235  unsigned FlatOpNo = Ops.getFlattenedOperandNumber(SrcOp);
236
237  if (!Ops[DestOp.first].Constraints[DestOp.second].isNone())
238    throw "Operand '" + DestOpName + "' cannot have multiple constraints!";
239  Ops[DestOp.first].Constraints[DestOp.second] =
240  CGIOperandList::ConstraintInfo::getTied(FlatOpNo);
241}
242
243static void ParseConstraints(const std::string &CStr, CGIOperandList &Ops) {
244  if (CStr.empty()) return;
245
246  const std::string delims(",");
247  std::string::size_type bidx, eidx;
248
249  bidx = CStr.find_first_not_of(delims);
250  while (bidx != std::string::npos) {
251    eidx = CStr.find_first_of(delims, bidx);
252    if (eidx == std::string::npos)
253      eidx = CStr.length();
254
255    ParseConstraint(CStr.substr(bidx, eidx - bidx), Ops);
256    bidx = CStr.find_first_not_of(delims, eidx);
257  }
258}
259
260void CGIOperandList::ProcessDisableEncoding(std::string DisableEncoding) {
261  while (1) {
262    std::string OpName;
263    tie(OpName, DisableEncoding) = getToken(DisableEncoding, " ,\t");
264    if (OpName.empty()) break;
265
266    // Figure out which operand this is.
267    std::pair<unsigned,unsigned> Op = ParseOperandName(OpName, false);
268
269    // Mark the operand as not-to-be encoded.
270    if (Op.second >= OperandList[Op.first].DoNotEncode.size())
271      OperandList[Op.first].DoNotEncode.resize(Op.second+1);
272    OperandList[Op.first].DoNotEncode[Op.second] = true;
273  }
274
275}
276
277//===----------------------------------------------------------------------===//
278// CodeGenInstruction Implementation
279//===----------------------------------------------------------------------===//
280
281CodeGenInstruction::CodeGenInstruction(Record *R) : TheDef(R), Operands(R) {
282  Namespace = R->getValueAsString("Namespace");
283  AsmString = R->getValueAsString("AsmString");
284
285  isReturn     = R->getValueAsBit("isReturn");
286  isBranch     = R->getValueAsBit("isBranch");
287  isIndirectBranch = R->getValueAsBit("isIndirectBranch");
288  isCompare    = R->getValueAsBit("isCompare");
289  isBarrier    = R->getValueAsBit("isBarrier");
290  isCall       = R->getValueAsBit("isCall");
291  canFoldAsLoad = R->getValueAsBit("canFoldAsLoad");
292  mayLoad      = R->getValueAsBit("mayLoad");
293  mayStore     = R->getValueAsBit("mayStore");
294  isPredicable = Operands.isPredicable || R->getValueAsBit("isPredicable");
295  isConvertibleToThreeAddress = R->getValueAsBit("isConvertibleToThreeAddress");
296  isCommutable = R->getValueAsBit("isCommutable");
297  isTerminator = R->getValueAsBit("isTerminator");
298  isReMaterializable = R->getValueAsBit("isReMaterializable");
299  hasDelaySlot = R->getValueAsBit("hasDelaySlot");
300  usesCustomInserter = R->getValueAsBit("usesCustomInserter");
301  hasCtrlDep   = R->getValueAsBit("hasCtrlDep");
302  isNotDuplicable = R->getValueAsBit("isNotDuplicable");
303  hasSideEffects = R->getValueAsBit("hasSideEffects");
304  neverHasSideEffects = R->getValueAsBit("neverHasSideEffects");
305  isAsCheapAsAMove = R->getValueAsBit("isAsCheapAsAMove");
306  hasExtraSrcRegAllocReq = R->getValueAsBit("hasExtraSrcRegAllocReq");
307  hasExtraDefRegAllocReq = R->getValueAsBit("hasExtraDefRegAllocReq");
308  ImplicitDefs = R->getValueAsListOfDefs("Defs");
309  ImplicitUses = R->getValueAsListOfDefs("Uses");
310
311  if (neverHasSideEffects + hasSideEffects > 1)
312    throw R->getName() + ": multiple conflicting side-effect flags set!";
313
314  // Parse Constraints.
315  ParseConstraints(R->getValueAsString("Constraints"), Operands);
316
317  // Parse the DisableEncoding field.
318  Operands.ProcessDisableEncoding(R->getValueAsString("DisableEncoding"));
319}
320
321/// HasOneImplicitDefWithKnownVT - If the instruction has at least one
322/// implicit def and it has a known VT, return the VT, otherwise return
323/// MVT::Other.
324MVT::SimpleValueType CodeGenInstruction::
325HasOneImplicitDefWithKnownVT(const CodeGenTarget &TargetInfo) const {
326  if (ImplicitDefs.empty()) return MVT::Other;
327
328  // Check to see if the first implicit def has a resolvable type.
329  Record *FirstImplicitDef = ImplicitDefs[0];
330  assert(FirstImplicitDef->isSubClassOf("Register"));
331  const std::vector<MVT::SimpleValueType> &RegVTs =
332    TargetInfo.getRegisterVTs(FirstImplicitDef);
333  if (RegVTs.size() == 1)
334    return RegVTs[0];
335  return MVT::Other;
336}
337
338
339/// FlattenAsmStringVariants - Flatten the specified AsmString to only
340/// include text from the specified variant, returning the new string.
341std::string CodeGenInstruction::
342FlattenAsmStringVariants(StringRef Cur, unsigned Variant) {
343  std::string Res = "";
344
345  for (;;) {
346    // Find the start of the next variant string.
347    size_t VariantsStart = 0;
348    for (size_t e = Cur.size(); VariantsStart != e; ++VariantsStart)
349      if (Cur[VariantsStart] == '{' &&
350          (VariantsStart == 0 || (Cur[VariantsStart-1] != '$' &&
351                                  Cur[VariantsStart-1] != '\\')))
352        break;
353
354    // Add the prefix to the result.
355    Res += Cur.slice(0, VariantsStart);
356    if (VariantsStart == Cur.size())
357      break;
358
359    ++VariantsStart; // Skip the '{'.
360
361    // Scan to the end of the variants string.
362    size_t VariantsEnd = VariantsStart;
363    unsigned NestedBraces = 1;
364    for (size_t e = Cur.size(); VariantsEnd != e; ++VariantsEnd) {
365      if (Cur[VariantsEnd] == '}' && Cur[VariantsEnd-1] != '\\') {
366        if (--NestedBraces == 0)
367          break;
368      } else if (Cur[VariantsEnd] == '{')
369        ++NestedBraces;
370    }
371
372    // Select the Nth variant (or empty).
373    StringRef Selection = Cur.slice(VariantsStart, VariantsEnd);
374    for (unsigned i = 0; i != Variant; ++i)
375      Selection = Selection.split('|').second;
376    Res += Selection.split('|').first;
377
378    assert(VariantsEnd != Cur.size() &&
379           "Unterminated variants in assembly string!");
380    Cur = Cur.substr(VariantsEnd + 1);
381  }
382
383  return Res;
384}
385
386
387//===----------------------------------------------------------------------===//
388/// CodeGenInstAlias Implementation
389//===----------------------------------------------------------------------===//
390
391CodeGenInstAlias::CodeGenInstAlias(Record *R, CodeGenTarget &T) : TheDef(R) {
392  AsmString = R->getValueAsString("AsmString");
393  Result = R->getValueAsDag("ResultInst");
394
395  // Verify that the root of the result is an instruction.
396  DefInit *DI = dynamic_cast<DefInit*>(Result->getOperator());
397  if (DI == 0 || !DI->getDef()->isSubClassOf("Instruction"))
398    throw TGError(R->getLoc(), "result of inst alias should be an instruction");
399
400  ResultInst = &T.getInstruction(DI->getDef());
401
402  // NameClass - If argument names are repeated, we need to verify they have
403  // the same class.
404  StringMap<Record*> NameClass;
405
406  // Decode and validate the arguments of the result.
407  unsigned AliasOpNo = 0;
408  for (unsigned i = 0, e = ResultInst->Operands.size(); i != e; ++i) {
409    // Tied registers don't have an entry in the result dag.
410    if (ResultInst->Operands[i].getTiedRegister() != -1)
411      continue;
412
413    if (AliasOpNo >= Result->getNumArgs())
414      throw TGError(R->getLoc(), "result has " + utostr(Result->getNumArgs()) +
415                    " arguments, but " + ResultInst->TheDef->getName() +
416                    " instruction expects " +
417                    utostr(ResultInst->Operands.size()) + " operands!");
418
419
420    Init *Arg = Result->getArg(AliasOpNo);
421    Record *ResultOpRec = ResultInst->Operands[i].Rec;
422
423    // Handle explicit registers.
424    if (DefInit *ADI = dynamic_cast<DefInit*>(Arg)) {
425      if (ADI->getDef()->isSubClassOf("Register")) {
426        if (!Result->getArgName(AliasOpNo).empty())
427          throw TGError(R->getLoc(), "result fixed register argument must "
428                        "not have a name!");
429
430        if (!ResultOpRec->isSubClassOf("RegisterClass"))
431          throw TGError(R->getLoc(), "result fixed register argument is not "
432                        "passed to a RegisterClass operand!");
433
434        if (!T.getRegisterClass(ResultOpRec).containsRegister(ADI->getDef()))
435          throw TGError(R->getLoc(), "fixed register " +ADI->getDef()->getName()
436                        + " is not a member of the " + ResultOpRec->getName() +
437                        " register class!");
438
439        // Now that it is validated, add it.
440        ResultOperands.push_back(ResultOperand(ADI->getDef()));
441        ++AliasOpNo;
442        continue;
443      }
444    }
445
446    // If the operand is a record, it must have a name, and the record type must
447    // match up with the instruction's argument type.
448    if (DefInit *ADI = dynamic_cast<DefInit*>(Arg)) {
449      if (Result->getArgName(AliasOpNo).empty())
450        throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
451                      " must have a name!");
452
453      if (ADI->getDef() != ResultOpRec)
454        throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
455                      " declared with class " + ADI->getDef()->getName() +
456                      ", instruction operand is class " +
457                      ResultOpRec->getName());
458
459      // Verify we don't have something like: (someinst GR16:$foo, GR32:$foo)
460      // $foo can exist multiple times in the result list, but it must have the
461      // same type.
462      Record *&Entry = NameClass[Result->getArgName(AliasOpNo)];
463      if (Entry && Entry != ADI->getDef())
464        throw TGError(R->getLoc(), "result value $" +
465                      Result->getArgName(AliasOpNo) +
466                      " is both " + Entry->getName() + " and " +
467                      ADI->getDef()->getName() + "!");
468
469      // Now that it is validated, add it.
470      ResultOperands.push_back(ResultOperand(Result->getArgName(AliasOpNo),
471                                             ADI->getDef()));
472      ++AliasOpNo;
473      continue;
474    }
475
476    if (IntInit *II = dynamic_cast<IntInit*>(Arg)) {
477      // Integer arguments can't have names.
478      if (!Result->getArgName(AliasOpNo).empty())
479        throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
480                      " must not have a name!");
481      if (ResultInst->Operands[i].MINumOperands != 1 ||
482          !ResultOpRec->isSubClassOf("Operand"))
483        throw TGError(R->getLoc(), "invalid argument class " +
484                      ResultOpRec->getName() +
485                      " for integer result operand!");
486      ResultOperands.push_back(ResultOperand(II->getValue()));
487      ++AliasOpNo;
488      continue;
489    }
490
491    throw TGError(R->getLoc(), "result of inst alias has unknown operand type");
492  }
493
494  if (AliasOpNo != Result->getNumArgs())
495    throw TGError(R->getLoc(), "result has " + utostr(Result->getNumArgs()) +
496                  " arguments, but " + ResultInst->TheDef->getName() +
497                  " instruction expects " + utostr(ResultInst->Operands.size())+
498                  " operands!");
499}
500
501/// getResultInstOperandIndexForResultOperandIndex - Given an index into the
502/// ResultOperands array, translate it to a valid index in ResultInst's
503/// operand list.
504unsigned CodeGenInstAlias::
505getResultInstOperandIndexForResultOperandIndex(unsigned OpNo) const {
506  unsigned OpIdx = 0;
507
508  for (unsigned i = 0;; ++i) {
509    assert(i != ResultInst->Operands.size() && "Didn't find entry");
510    if (ResultInst->Operands[i].getTiedRegister() != -1)
511      continue;
512
513    if (OpIdx == OpNo) return i;
514
515    ++OpIdx;
516  }
517}
518