utils/TableGen/CodeGenInstruction.cpp

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