CodeGenInstruction.cpp revision 98c870f87b7f0c996a9ba67003d88d434d6dbcd0 
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      if (Rec->getValue("EncoderMethod"))
75        EncoderMethod = Rec->getValueAsString("EncoderMethod");
76      MIOpInfo = Rec->getValueAsDag("MIOperandInfo");
77
78      // Verify that MIOpInfo has an 'ops' root value.
79      if (!dynamic_cast<DefInit*>(MIOpInfo->getOperator()) ||
80          dynamic_cast<DefInit*>(MIOpInfo->getOperator())
81          ->getDef()->getName() != "ops")
82        throw "Bad value for MIOperandInfo in operand '" + Rec->getName() +
83        "'\n";
84
85      // If we have MIOpInfo, then we have #operands equal to number of entries
86      // in MIOperandInfo.
87      if (unsigned NumArgs = MIOpInfo->getNumArgs())
88        NumOps = NumArgs;
89
90      if (Rec->isSubClassOf("PredicateOperand"))
91        isPredicable = true;
92      else if (Rec->isSubClassOf("OptionalDefOperand"))
93        hasOptionalDef = true;
94    } else if (Rec->getName() == "variable_ops") {
95      isVariadic = true;
96      continue;
97    } else if (!Rec->isSubClassOf("RegisterClass") &&
98               Rec->getName() != "ptr_rc" && Rec->getName() != "unknown")
99      throw "Unknown operand class '" + Rec->getName() +
100      "' in '" + R->getName() + "' instruction!";
101
102    // Check that the operand has a name and that it's unique.
103    if (ArgName.empty())
104      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
105      " has no name!";
106    if (!OperandNames.insert(ArgName).second)
107      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
108      " has the same name as a previous operand!";
109
110    OperandList.push_back(OperandInfo(Rec, ArgName, PrintMethod, EncoderMethod,
111                                      MIOperandNo, NumOps, MIOpInfo));
112    MIOperandNo += NumOps;
113  }
114
115
116  // Make sure the constraints list for each operand is large enough to hold
117  // constraint info, even if none is present.
118  for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
119    OperandList[i].Constraints.resize(OperandList[i].MINumOperands);
120}
121
122
123/// getOperandNamed - Return the index of the operand with the specified
124/// non-empty name.  If the instruction does not have an operand with the
125/// specified name, throw an exception.
126///
127unsigned CGIOperandList::getOperandNamed(StringRef Name) const {
128  unsigned OpIdx;
129  if (hasOperandNamed(Name, OpIdx)) return OpIdx;
130  throw "'" + TheDef->getName() + "' does not have an operand named '$" +
131    Name.str() + "'!";
132}
133
134/// hasOperandNamed - Query whether the instruction has an operand of the
135/// given name. If so, return true and set OpIdx to the index of the
136/// operand. Otherwise, return false.
137bool CGIOperandList::hasOperandNamed(StringRef Name, unsigned &OpIdx) const {
138  assert(!Name.empty() && "Cannot search for operand with no name!");
139  for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
140    if (OperandList[i].Name == Name) {
141      OpIdx = i;
142      return true;
143    }
144  return false;
145}
146
147std::pair<unsigned,unsigned>
148CGIOperandList::ParseOperandName(const std::string &Op, bool AllowWholeOp) {
149  if (Op.empty() || Op[0] != '$')
150    throw TheDef->getName() + ": Illegal operand name: '" + Op + "'";
151
152  std::string OpName = Op.substr(1);
153  std::string SubOpName;
154
155  // Check to see if this is $foo.bar.
156  std::string::size_type DotIdx = OpName.find_first_of(".");
157  if (DotIdx != std::string::npos) {
158    SubOpName = OpName.substr(DotIdx+1);
159    if (SubOpName.empty())
160      throw TheDef->getName() + ": illegal empty suboperand name in '" +Op +"'";
161    OpName = OpName.substr(0, DotIdx);
162  }
163
164  unsigned OpIdx = getOperandNamed(OpName);
165
166  if (SubOpName.empty()) {  // If no suboperand name was specified:
167    // If one was needed, throw.
168    if (OperandList[OpIdx].MINumOperands > 1 && !AllowWholeOp &&
169        SubOpName.empty())
170      throw TheDef->getName() + ": Illegal to refer to"
171      " whole operand part of complex operand '" + Op + "'";
172
173    // Otherwise, return the operand.
174    return std::make_pair(OpIdx, 0U);
175  }
176
177  // Find the suboperand number involved.
178  DagInit *MIOpInfo = OperandList[OpIdx].MIOperandInfo;
179  if (MIOpInfo == 0)
180    throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
181
182  // Find the operand with the right name.
183  for (unsigned i = 0, e = MIOpInfo->getNumArgs(); i != e; ++i)
184    if (MIOpInfo->getArgName(i) == SubOpName)
185      return std::make_pair(OpIdx, i);
186
187  // Otherwise, didn't find it!
188  throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
189}
190
191static void ParseConstraint(const std::string &CStr, CGIOperandList &Ops) {
192  // EARLY_CLOBBER: @early $reg
193  std::string::size_type wpos = CStr.find_first_of(" \t");
194  std::string::size_type start = CStr.find_first_not_of(" \t");
195  std::string Tok = CStr.substr(start, wpos - start);
196  if (Tok == "@earlyclobber") {
197    std::string Name = CStr.substr(wpos+1);
198    wpos = Name.find_first_not_of(" \t");
199    if (wpos == std::string::npos)
200      throw "Illegal format for @earlyclobber constraint: '" + CStr + "'";
201    Name = Name.substr(wpos);
202    std::pair<unsigned,unsigned> Op = Ops.ParseOperandName(Name, false);
203
204    // Build the string for the operand
205    if (!Ops[Op.first].Constraints[Op.second].isNone())
206      throw "Operand '" + Name + "' cannot have multiple constraints!";
207    Ops[Op.first].Constraints[Op.second] =
208    CGIOperandList::ConstraintInfo::getEarlyClobber();
209    return;
210  }
211
212  // Only other constraint is "TIED_TO" for now.
213  std::string::size_type pos = CStr.find_first_of('=');
214  assert(pos != std::string::npos && "Unrecognized constraint");
215  start = CStr.find_first_not_of(" \t");
216  std::string Name = CStr.substr(start, pos - start);
217
218  // TIED_TO: $src1 = $dst
219  wpos = Name.find_first_of(" \t");
220  if (wpos == std::string::npos)
221    throw "Illegal format for tied-to constraint: '" + CStr + "'";
222  std::string DestOpName = Name.substr(0, wpos);
223  std::pair<unsigned,unsigned> DestOp = Ops.ParseOperandName(DestOpName, false);
224
225  Name = CStr.substr(pos+1);
226  wpos = Name.find_first_not_of(" \t");
227  if (wpos == std::string::npos)
228    throw "Illegal format for tied-to constraint: '" + CStr + "'";
229
230  std::pair<unsigned,unsigned> SrcOp =
231  Ops.ParseOperandName(Name.substr(wpos), false);
232  if (SrcOp > DestOp)
233    throw "Illegal tied-to operand constraint '" + CStr + "'";
234
235
236  unsigned FlatOpNo = Ops.getFlattenedOperandNumber(SrcOp);
237
238  if (!Ops[DestOp.first].Constraints[DestOp.second].isNone())
239    throw "Operand '" + DestOpName + "' cannot have multiple constraints!";
240  Ops[DestOp.first].Constraints[DestOp.second] =
241  CGIOperandList::ConstraintInfo::getTied(FlatOpNo);
242}
243
244static void ParseConstraints(const std::string &CStr, CGIOperandList &Ops) {
245  if (CStr.empty()) return;
246
247  const std::string delims(",");
248  std::string::size_type bidx, eidx;
249
250  bidx = CStr.find_first_not_of(delims);
251  while (bidx != std::string::npos) {
252    eidx = CStr.find_first_of(delims, bidx);
253    if (eidx == std::string::npos)
254      eidx = CStr.length();
255
256    ParseConstraint(CStr.substr(bidx, eidx - bidx), Ops);
257    bidx = CStr.find_first_not_of(delims, eidx);
258  }
259}
260
261void CGIOperandList::ProcessDisableEncoding(std::string DisableEncoding) {
262  while (1) {
263    std::string OpName;
264    tie(OpName, DisableEncoding) = getToken(DisableEncoding, " ,\t");
265    if (OpName.empty()) break;
266
267    // Figure out which operand this is.
268    std::pair<unsigned,unsigned> Op = ParseOperandName(OpName, false);
269
270    // Mark the operand as not-to-be encoded.
271    if (Op.second >= OperandList[Op.first].DoNotEncode.size())
272      OperandList[Op.first].DoNotEncode.resize(Op.second+1);
273    OperandList[Op.first].DoNotEncode[Op.second] = true;
274  }
275
276}
277
278//===----------------------------------------------------------------------===//
279// CodeGenInstruction Implementation
280//===----------------------------------------------------------------------===//
281
282CodeGenInstruction::CodeGenInstruction(Record *R) : TheDef(R), Operands(R) {
283  Namespace = R->getValueAsString("Namespace");
284  AsmString = R->getValueAsString("AsmString");
285
286  isReturn     = R->getValueAsBit("isReturn");
287  isBranch     = R->getValueAsBit("isBranch");
288  isIndirectBranch = R->getValueAsBit("isIndirectBranch");
289  isCompare    = R->getValueAsBit("isCompare");
290  isBarrier    = R->getValueAsBit("isBarrier");
291  isCall       = R->getValueAsBit("isCall");
292  canFoldAsLoad = R->getValueAsBit("canFoldAsLoad");
293  mayLoad      = R->getValueAsBit("mayLoad");
294  mayStore     = R->getValueAsBit("mayStore");
295  isPredicable = Operands.isPredicable || R->getValueAsBit("isPredicable");
296  isConvertibleToThreeAddress = R->getValueAsBit("isConvertibleToThreeAddress");
297  isCommutable = R->getValueAsBit("isCommutable");
298  isTerminator = R->getValueAsBit("isTerminator");
299  isReMaterializable = R->getValueAsBit("isReMaterializable");
300  hasDelaySlot = R->getValueAsBit("hasDelaySlot");
301  usesCustomInserter = R->getValueAsBit("usesCustomInserter");
302  hasCtrlDep   = R->getValueAsBit("hasCtrlDep");
303  isNotDuplicable = R->getValueAsBit("isNotDuplicable");
304  hasSideEffects = R->getValueAsBit("hasSideEffects");
305  neverHasSideEffects = R->getValueAsBit("neverHasSideEffects");
306  isAsCheapAsAMove = R->getValueAsBit("isAsCheapAsAMove");
307  hasExtraSrcRegAllocReq = R->getValueAsBit("hasExtraSrcRegAllocReq");
308  hasExtraDefRegAllocReq = R->getValueAsBit("hasExtraDefRegAllocReq");
309  ImplicitDefs = R->getValueAsListOfDefs("Defs");
310  ImplicitUses = R->getValueAsListOfDefs("Uses");
311
312  if (neverHasSideEffects + hasSideEffects > 1)
313    throw R->getName() + ": multiple conflicting side-effect flags set!";
314
315  // Parse Constraints.
316  ParseConstraints(R->getValueAsString("Constraints"), Operands);
317
318  // Parse the DisableEncoding field.
319  Operands.ProcessDisableEncoding(R->getValueAsString("DisableEncoding"));
320}
321
322/// HasOneImplicitDefWithKnownVT - If the instruction has at least one
323/// implicit def and it has a known VT, return the VT, otherwise return
324/// MVT::Other.
325MVT::SimpleValueType CodeGenInstruction::
326HasOneImplicitDefWithKnownVT(const CodeGenTarget &TargetInfo) const {
327  if (ImplicitDefs.empty()) return MVT::Other;
328
329  // Check to see if the first implicit def has a resolvable type.
330  Record *FirstImplicitDef = ImplicitDefs[0];
331  assert(FirstImplicitDef->isSubClassOf("Register"));
332  const std::vector<MVT::SimpleValueType> &RegVTs =
333    TargetInfo.getRegisterVTs(FirstImplicitDef);
334  if (RegVTs.size() == 1)
335    return RegVTs[0];
336  return MVT::Other;
337}
338
339
340/// FlattenAsmStringVariants - Flatten the specified AsmString to only
341/// include text from the specified variant, returning the new string.
342std::string CodeGenInstruction::
343FlattenAsmStringVariants(StringRef Cur, unsigned Variant) {
344  std::string Res = "";
345
346  for (;;) {
347    // Find the start of the next variant string.
348    size_t VariantsStart = 0;
349    for (size_t e = Cur.size(); VariantsStart != e; ++VariantsStart)
350      if (Cur[VariantsStart] == '{' &&
351          (VariantsStart == 0 || (Cur[VariantsStart-1] != '$' &&
352                                  Cur[VariantsStart-1] != '\\')))
353        break;
354
355    // Add the prefix to the result.
356    Res += Cur.slice(0, VariantsStart);
357    if (VariantsStart == Cur.size())
358      break;
359
360    ++VariantsStart; // Skip the '{'.
361
362    // Scan to the end of the variants string.
363    size_t VariantsEnd = VariantsStart;
364    unsigned NestedBraces = 1;
365    for (size_t e = Cur.size(); VariantsEnd != e; ++VariantsEnd) {
366      if (Cur[VariantsEnd] == '}' && Cur[VariantsEnd-1] != '\\') {
367        if (--NestedBraces == 0)
368          break;
369      } else if (Cur[VariantsEnd] == '{')
370        ++NestedBraces;
371    }
372
373    // Select the Nth variant (or empty).
374    StringRef Selection = Cur.slice(VariantsStart, VariantsEnd);
375    for (unsigned i = 0; i != Variant; ++i)
376      Selection = Selection.split('|').second;
377    Res += Selection.split('|').first;
378
379    assert(VariantsEnd != Cur.size() &&
380           "Unterminated variants in assembly string!");
381    Cur = Cur.substr(VariantsEnd + 1);
382  }
383
384  return Res;
385}
386
387
388//===----------------------------------------------------------------------===//
389/// CodeGenInstAlias Implementation
390//===----------------------------------------------------------------------===//
391
392CodeGenInstAlias::CodeGenInstAlias(Record *R, CodeGenTarget &T) : TheDef(R) {
393  AsmString = R->getValueAsString("AsmString");
394  Result = R->getValueAsDag("ResultInst");
395
396  // Verify that the root of the result is an instruction.
397  DefInit *DI = dynamic_cast<DefInit*>(Result->getOperator());
398  if (DI == 0 || !DI->getDef()->isSubClassOf("Instruction"))
399    throw TGError(R->getLoc(), "result of inst alias should be an instruction");
400
401  ResultInst = &T.getInstruction(DI->getDef());
402
403  // NameClass - If argument names are repeated, we need to verify they have
404  // the same class.
405  StringMap<Record*> NameClass;
406
407  // Decode and validate the arguments of the result.
408  unsigned AliasOpNo = 0;
409  for (unsigned i = 0, e = ResultInst->Operands.size(); i != e; ++i) {
410    // Tied registers don't have an entry in the result dag.
411    if (ResultInst->Operands[i].getTiedRegister() != -1)
412      continue;
413
414    if (AliasOpNo >= Result->getNumArgs())
415      throw TGError(R->getLoc(), "result has " + utostr(Result->getNumArgs()) +
416                    " arguments, but " + ResultInst->TheDef->getName() +
417                    " instruction expects " +
418                    utostr(ResultInst->Operands.size()) + " operands!");
419
420
421    Init *Arg = Result->getArg(AliasOpNo);
422
423    // If the operand is a record, it must have a name, and the record type must
424    // match up with the instruction's argument type.
425    if (DefInit *ADI = dynamic_cast<DefInit*>(Arg)) {
426      if (Result->getArgName(AliasOpNo).empty())
427        throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
428                      " must have a name!");
429
430      if (ADI->getDef() != ResultInst->Operands[i].Rec)
431        throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
432                      " declared with class " + ADI->getDef()->getName() +
433                      ", instruction operand is class " +
434                      ResultInst->Operands[i].Rec->getName());
435
436      // Verify we don't have something like: (someinst GR16:$foo, GR32:$foo)
437      // $foo can exist multiple times in the result list, but it must have the
438      // same type.
439      Record *&Entry = NameClass[Result->getArgName(AliasOpNo)];
440      if (Entry && Entry != ADI->getDef())
441        throw TGError(R->getLoc(), "result value $" +
442                      Result->getArgName(AliasOpNo) +
443                      " is both " + Entry->getName() + " and " +
444                      ADI->getDef()->getName() + "!");
445
446      // Now that it is validated, add it.
447      ResultOperands.push_back(ResultOperand(Result->getArgName(AliasOpNo),
448                                             ADI->getDef()));
449      ++AliasOpNo;
450      continue;
451    }
452
453    if (IntInit *II = dynamic_cast<IntInit*>(Arg)) {
454      // Integer arguments can't have names.
455      if (!Result->getArgName(AliasOpNo).empty())
456        throw TGError(R->getLoc(), "result argument #" + utostr(AliasOpNo) +
457                      " must not have a name!");
458      if (ResultInst->Operands[i].MINumOperands != 1 ||
459          !ResultInst->Operands[i].Rec->isSubClassOf("Operand"))
460        throw TGError(R->getLoc(), "invalid argument class " +
461                      ResultInst->Operands[i].Rec->getName() +
462                      " for integer result operand!");
463      ResultOperands.push_back(ResultOperand(II->getValue()));
464      ++AliasOpNo;
465      continue;
466    }
467
468    throw TGError(R->getLoc(), "result of inst alias has unknown operand type");
469  }
470
471  if (AliasOpNo != Result->getNumArgs())
472    throw TGError(R->getLoc(), "result has " + utostr(Result->getNumArgs()) +
473                  " arguments, but " + ResultInst->TheDef->getName() +
474                  " instruction expects " + utostr(ResultInst->Operands.size())+
475                  " operands!");
476}
477
478/// getResultInstOperandIndexForResultOperandIndex - Given an index into the
479/// ResultOperands array, translate it to a valid index in ResultInst's
480/// operand list.
481unsigned CodeGenInstAlias::
482getResultInstOperandIndexForResultOperandIndex(unsigned OpNo) const {
483  unsigned OpIdx = 0;
484
485  for (unsigned i = 0;; ++i) {
486    assert(i != ResultInst->Operands.size() && "Didn't find entry");
487    if (ResultInst->Operands[i].getTiedRegister() != -1)
488      continue;
489
490    if (OpIdx == OpNo) return i;
491
492    ++OpIdx;
493  }
494}
495