CodeGenInstruction.cpp revision 834f1ce0312e3d00d836f9560cb63182c2c4570f 
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 "Record.h"
16#include "llvm/ADT/StringExtras.h"
17#include <set>
18using namespace llvm;
19
20static void ParseConstraint(const std::string &CStr, CodeGenInstruction *I) {
21  // FIXME: Only supports TIED_TO for now.
22  std::string::size_type pos = CStr.find_first_of('=');
23  assert(pos != std::string::npos && "Unrecognized constraint");
24  std::string Name = CStr.substr(0, pos);
25
26  // TIED_TO: $src1 = $dst
27  std::string::size_type wpos = Name.find_first_of(" \t");
28  if (wpos == std::string::npos)
29    throw "Illegal format for tied-to constraint: '" + CStr + "'";
30  std::string DestOpName = Name.substr(0, wpos);
31  std::pair<unsigned,unsigned> DestOp = I->ParseOperandName(DestOpName, false);
32
33  Name = CStr.substr(pos+1);
34  wpos = Name.find_first_not_of(" \t");
35  if (wpos == std::string::npos)
36    throw "Illegal format for tied-to constraint: '" + CStr + "'";
37
38  std::pair<unsigned,unsigned> SrcOp =
39  I->ParseOperandName(Name.substr(wpos), false);
40  if (SrcOp > DestOp)
41    throw "Illegal tied-to operand constraint '" + CStr + "'";
42
43
44  unsigned FlatOpNo = I->getFlattenedOperandNumber(SrcOp);
45  // Build the string for the operand.
46  std::string OpConstraint =
47  "((" + utostr(FlatOpNo) + " << 16) | (1 << TOI::TIED_TO))";
48
49
50  if (!I->OperandList[DestOp.first].Constraints[DestOp.second].empty())
51    throw "Operand '" + DestOpName + "' cannot have multiple constraints!";
52  I->OperandList[DestOp.first].Constraints[DestOp.second] = OpConstraint;
53}
54
55static void ParseConstraints(const std::string &CStr, CodeGenInstruction *I) {
56  // Make sure the constraints list for each operand is large enough to hold
57  // constraint info, even if none is present.
58  for (unsigned i = 0, e = I->OperandList.size(); i != e; ++i)
59    I->OperandList[i].Constraints.resize(I->OperandList[i].MINumOperands);
60
61  if (CStr.empty()) return;
62
63  const std::string delims(",");
64  std::string::size_type bidx, eidx;
65
66  bidx = CStr.find_first_not_of(delims);
67  while (bidx != std::string::npos) {
68    eidx = CStr.find_first_of(delims, bidx);
69    if (eidx == std::string::npos)
70      eidx = CStr.length();
71
72    ParseConstraint(CStr.substr(bidx, eidx), I);
73    bidx = CStr.find_first_not_of(delims, eidx);
74  }
75}
76
77CodeGenInstruction::CodeGenInstruction(Record *R, const std::string &AsmStr)
78  : TheDef(R), AsmString(AsmStr) {
79  Name      = R->getValueAsString("Name");
80  Namespace = R->getValueAsString("Namespace");
81
82  isReturn     = R->getValueAsBit("isReturn");
83  isBranch     = R->getValueAsBit("isBranch");
84  isIndirectBranch = R->getValueAsBit("isIndirectBranch");
85  isBarrier    = R->getValueAsBit("isBarrier");
86  isCall       = R->getValueAsBit("isCall");
87  isSimpleLoad = R->getValueAsBit("isSimpleLoad");
88  mayStore     = R->getValueAsBit("mayStore");
89  isImplicitDef= R->getValueAsBit("isImplicitDef");
90  bool isTwoAddress = R->getValueAsBit("isTwoAddress");
91  isPredicable = R->getValueAsBit("isPredicable");
92  isConvertibleToThreeAddress = R->getValueAsBit("isConvertibleToThreeAddress");
93  isCommutable = R->getValueAsBit("isCommutable");
94  isTerminator = R->getValueAsBit("isTerminator");
95  isReMaterializable = R->getValueAsBit("isReMaterializable");
96  hasDelaySlot = R->getValueAsBit("hasDelaySlot");
97  usesCustomDAGSchedInserter = R->getValueAsBit("usesCustomDAGSchedInserter");
98  hasCtrlDep   = R->getValueAsBit("hasCtrlDep");
99  isNotDuplicable = R->getValueAsBit("isNotDuplicable");
100  mayHaveSideEffects = R->getValueAsBit("mayHaveSideEffects");
101  neverHasSideEffects = R->getValueAsBit("neverHasSideEffects");
102  hasOptionalDef = false;
103  hasVariableNumberOfOperands = false;
104
105  if (mayHaveSideEffects && neverHasSideEffects)
106    throw R->getName() +
107      ": cannot have both 'mayHaveSideEffects' and 'neverHasSideEffects' set!";
108
109  DagInit *DI;
110  try {
111    DI = R->getValueAsDag("OutOperandList");
112  } catch (...) {
113    // Error getting operand list, just ignore it (sparcv9).
114    AsmString.clear();
115    OperandList.clear();
116    return;
117  }
118  NumDefs = DI->getNumArgs();
119
120  DagInit *IDI;
121  try {
122    IDI = R->getValueAsDag("InOperandList");
123  } catch (...) {
124    // Error getting operand list, just ignore it (sparcv9).
125    AsmString.clear();
126    OperandList.clear();
127    return;
128  }
129  DI = (DagInit*)(new BinOpInit(BinOpInit::CONCAT, DI, IDI))->Fold();
130
131  unsigned MIOperandNo = 0;
132  std::set<std::string> OperandNames;
133  for (unsigned i = 0, e = DI->getNumArgs(); i != e; ++i) {
134    DefInit *Arg = dynamic_cast<DefInit*>(DI->getArg(i));
135    if (!Arg)
136      throw "Illegal operand for the '" + R->getName() + "' instruction!";
137
138    Record *Rec = Arg->getDef();
139    std::string PrintMethod = "printOperand";
140    unsigned NumOps = 1;
141    DagInit *MIOpInfo = 0;
142    if (Rec->isSubClassOf("Operand")) {
143      PrintMethod = Rec->getValueAsString("PrintMethod");
144      MIOpInfo = Rec->getValueAsDag("MIOperandInfo");
145
146      // Verify that MIOpInfo has an 'ops' root value.
147      if (!dynamic_cast<DefInit*>(MIOpInfo->getOperator()) ||
148          dynamic_cast<DefInit*>(MIOpInfo->getOperator())
149               ->getDef()->getName() != "ops")
150        throw "Bad value for MIOperandInfo in operand '" + Rec->getName() +
151              "'\n";
152
153      // If we have MIOpInfo, then we have #operands equal to number of entries
154      // in MIOperandInfo.
155      if (unsigned NumArgs = MIOpInfo->getNumArgs())
156        NumOps = NumArgs;
157
158      if (Rec->isSubClassOf("PredicateOperand"))
159        isPredicable = true;
160      else if (Rec->isSubClassOf("OptionalDefOperand"))
161        hasOptionalDef = true;
162    } else if (Rec->getName() == "variable_ops") {
163      hasVariableNumberOfOperands = true;
164      continue;
165    } else if (!Rec->isSubClassOf("RegisterClass") &&
166               Rec->getName() != "ptr_rc")
167      throw "Unknown operand class '" + Rec->getName() +
168            "' in instruction '" + R->getName() + "' instruction!";
169
170    // Check that the operand has a name and that it's unique.
171    if (DI->getArgName(i).empty())
172      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
173        " has no name!";
174    if (!OperandNames.insert(DI->getArgName(i)).second)
175      throw "In instruction '" + R->getName() + "', operand #" + utostr(i) +
176        " has the same name as a previous operand!";
177
178    OperandList.push_back(OperandInfo(Rec, DI->getArgName(i), PrintMethod,
179                                      MIOperandNo, NumOps, MIOpInfo));
180    MIOperandNo += NumOps;
181  }
182
183  // Parse Constraints.
184  ParseConstraints(R->getValueAsString("Constraints"), this);
185
186  // For backward compatibility: isTwoAddress means operand 1 is tied to
187  // operand 0.
188  if (isTwoAddress) {
189    if (!OperandList[1].Constraints[0].empty())
190      throw R->getName() + ": cannot use isTwoAddress property: instruction "
191            "already has constraint set!";
192    OperandList[1].Constraints[0] = "((0 << 16) | (1 << TOI::TIED_TO))";
193  }
194
195  // Any operands with unset constraints get 0 as their constraint.
196  for (unsigned op = 0, e = OperandList.size(); op != e; ++op)
197    for (unsigned j = 0, e = OperandList[op].MINumOperands; j != e; ++j)
198      if (OperandList[op].Constraints[j].empty())
199        OperandList[op].Constraints[j] = "0";
200
201  // Parse the DisableEncoding field.
202  std::string DisableEncoding = R->getValueAsString("DisableEncoding");
203  while (1) {
204    std::string OpName = getToken(DisableEncoding, " ,\t");
205    if (OpName.empty()) break;
206
207    // Figure out which operand this is.
208    std::pair<unsigned,unsigned> Op = ParseOperandName(OpName, false);
209
210    // Mark the operand as not-to-be encoded.
211    if (Op.second >= OperandList[Op.first].DoNotEncode.size())
212      OperandList[Op.first].DoNotEncode.resize(Op.second+1);
213    OperandList[Op.first].DoNotEncode[Op.second] = true;
214  }
215}
216
217/// getName - Return the contents of the instruction Name field if set,
218/// otherwise return the name of the def.
219std::string CodeGenInstruction::getName() const {
220  if (!Name.empty()) return Name;
221  return TheDef->getName();
222}
223
224
225/// getOperandNamed - Return the index of the operand with the specified
226/// non-empty name.  If the instruction does not have an operand with the
227/// specified name, throw an exception.
228///
229unsigned CodeGenInstruction::getOperandNamed(const std::string &Name) const {
230  assert(!Name.empty() && "Cannot search for operand with no name!");
231  for (unsigned i = 0, e = OperandList.size(); i != e; ++i)
232    if (OperandList[i].Name == Name) return i;
233  throw "Instruction '" + TheDef->getName() +
234        "' does not have an operand named '$" + Name + "'!";
235}
236
237std::pair<unsigned,unsigned>
238CodeGenInstruction::ParseOperandName(const std::string &Op,
239                                     bool AllowWholeOp) {
240  if (Op.empty() || Op[0] != '$')
241    throw TheDef->getName() + ": Illegal operand name: '" + Op + "'";
242
243  std::string OpName = Op.substr(1);
244  std::string SubOpName;
245
246  // Check to see if this is $foo.bar.
247  std::string::size_type DotIdx = OpName.find_first_of(".");
248  if (DotIdx != std::string::npos) {
249    SubOpName = OpName.substr(DotIdx+1);
250    if (SubOpName.empty())
251      throw TheDef->getName() + ": illegal empty suboperand name in '" +Op +"'";
252    OpName = OpName.substr(0, DotIdx);
253  }
254
255  unsigned OpIdx = getOperandNamed(OpName);
256
257  if (SubOpName.empty()) {  // If no suboperand name was specified:
258    // If one was needed, throw.
259    if (OperandList[OpIdx].MINumOperands > 1 && !AllowWholeOp &&
260        SubOpName.empty())
261      throw TheDef->getName() + ": Illegal to refer to"
262            " whole operand part of complex operand '" + Op + "'";
263
264    // Otherwise, return the operand.
265    return std::make_pair(OpIdx, 0U);
266  }
267
268  // Find the suboperand number involved.
269  DagInit *MIOpInfo = OperandList[OpIdx].MIOperandInfo;
270  if (MIOpInfo == 0)
271    throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
272
273  // Find the operand with the right name.
274  for (unsigned i = 0, e = MIOpInfo->getNumArgs(); i != e; ++i)
275    if (MIOpInfo->getArgName(i) == SubOpName)
276      return std::make_pair(OpIdx, i);
277
278  // Otherwise, didn't find it!
279  throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
280}
281