llvm/utils/TableGen/CallingConvEmitter.cpp

   1 //===- CallingConvEmitter.cpp - Generate calling conventions --------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This tablegen backend is responsible for emitting descriptions of the calling
  10 // conventions supported by this target.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "CodeGenTarget.h"
  15 #include "llvm/TableGen/Error.h"
  16 #include "llvm/TableGen/Record.h"
  17 #include "llvm/TableGen/TableGenBackend.h"
  18 #include <cassert>
  19 using namespace llvm;
  20
  21 namespace {
  22 class CallingConvEmitter {
  23   RecordKeeper &Records;
  24 public:
  25   explicit CallingConvEmitter(RecordKeeper &R) : Records(R) {}
  26
  27   void run(raw_ostream &o);
  28
  29 private:
  30   void EmitCallingConv(Record *CC, raw_ostream &O);
  31   void EmitAction(Record *Action, unsigned Indent, raw_ostream &O);
  32   unsigned Counter;
  33 };
  34 } // End anonymous namespace
  35
  36 void CallingConvEmitter::run(raw_ostream &O) {
  37   std::vector<Record*> CCs = Records.getAllDerivedDefinitions("CallingConv");
  38
  39   // Emit prototypes for all of the non-custom CC's so that they can forward ref
  40   // each other.
  41   Records.startTimer("Emit prototypes");
  42   for (Record *CC : CCs) {
  43     if (!CC->getValueAsBit("Custom")) {
  44       unsigned Pad = CC->getName().size();
  45       if (CC->getValueAsBit("Entry")) {
  46         O << "bool llvm::";
  47         Pad += 12;
  48       } else {
  49         O << "static bool ";
  50         Pad += 13;
  51       }
  52       O << CC->getName() << "(unsigned ValNo, MVT ValVT,\n"
  53         << std::string(Pad, ' ') << "MVT LocVT, CCValAssign::LocInfo LocInfo,\n"
  54         << std::string(Pad, ' ')
  55         << "ISD::ArgFlagsTy ArgFlags, CCState &State);\n";
  56     }
  57   }
  58
  59   // Emit each non-custom calling convention description in full.
  60   Records.startTimer("Emit full descriptions");
  61   for (Record *CC : CCs) {
  62     if (!CC->getValueAsBit("Custom"))
  63       EmitCallingConv(CC, O);
  64   }
  65 }
  66
  67
  68 void CallingConvEmitter::EmitCallingConv(Record *CC, raw_ostream &O) {
  69   ListInit *CCActions = CC->getValueAsListInit("Actions");
  70   Counter = 0;
  71
  72   O << "\n\n";
  73   unsigned Pad = CC->getName().size();
  74   if (CC->getValueAsBit("Entry")) {
  75     O << "bool llvm::";
  76     Pad += 12;
  77   } else {
  78     O << "static bool ";
  79     Pad += 13;
  80   }
  81   O << CC->getName() << "(unsigned ValNo, MVT ValVT,\n"
  82     << std::string(Pad, ' ') << "MVT LocVT, CCValAssign::LocInfo LocInfo,\n"
  83     << std::string(Pad, ' ') << "ISD::ArgFlagsTy ArgFlags, CCState &State) {\n";
  84   // Emit all of the actions, in order.
  85   for (unsigned i = 0, e = CCActions->size(); i != e; ++i) {
  86     O << "\n";
  87     EmitAction(CCActions->getElementAsRecord(i), 2, O);
  88   }
  89
  90   O << "\n  return true; // CC didn't match.\n";
  91   O << "}\n";
  92 }
  93
  94 void CallingConvEmitter::EmitAction(Record *Action,
  95                                     unsigned Indent, raw_ostream &O) {
  96   std::string IndentStr = std::string(Indent, ' ');
  97
  98   if (Action->isSubClassOf("CCPredicateAction")) {
  99     O << IndentStr << "if (";
 100
 101     if (Action->isSubClassOf("CCIfType")) {
 102       ListInit *VTs = Action->getValueAsListInit("VTs");
 103       for (unsigned i = 0, e = VTs->size(); i != e; ++i) {
 104         Record *VT = VTs->getElementAsRecord(i);
 105         if (i != 0) O << " ||\n    " << IndentStr;
 106         O << "LocVT == " << getEnumName(getValueType(VT));
 107       }
 108
 109     } else if (Action->isSubClassOf("CCIf")) {
 110       O << Action->getValueAsString("Predicate");
 111     } else {
 112       errs() << *Action;
 113       PrintFatalError(Action->getLoc(), "Unknown CCPredicateAction!");
 114     }
 115
 116     O << ") {\n";
 117     EmitAction(Action->getValueAsDef("SubAction"), Indent+2, O);
 118     O << IndentStr << "}\n";
 119   } else {
 120     if (Action->isSubClassOf("CCDelegateTo")) {
 121       Record *CC = Action->getValueAsDef("CC");
 122       O << IndentStr << "if (!" << CC->getName()
 123         << "(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State))\n"
 124         << IndentStr << "  return false;\n";
 125     } else if (Action->isSubClassOf("CCAssignToReg")) {
 126       ListInit *RegList = Action->getValueAsListInit("RegList");
 127       if (RegList->size() == 1) {
 128         O << IndentStr << "if (unsigned Reg = State.AllocateReg(";
 129         O << getQualifiedName(RegList->getElementAsRecord(0)) << ")) {\n";
 130       } else {
 131         O << IndentStr << "static const MCPhysReg RegList" << ++Counter
 132           << "[] = {\n";
 133         O << IndentStr << "  ";
 134         ListSeparator LS;
 135         for (unsigned i = 0, e = RegList->size(); i != e; ++i)
 136           O << LS << getQualifiedName(RegList->getElementAsRecord(i));
 137         O << "\n" << IndentStr << "};\n";
 138         O << IndentStr << "if (unsigned Reg = State.AllocateReg(RegList"
 139           << Counter << ")) {\n";
 140       }
 141       O << IndentStr << "  State.addLoc(CCValAssign::getReg(ValNo, ValVT, "
 142         << "Reg, LocVT, LocInfo));\n";
 143       O << IndentStr << "  return false;\n";
 144       O << IndentStr << "}\n";
 145     } else if (Action->isSubClassOf("CCAssignToRegWithShadow")) {
 146       ListInit *RegList = Action->getValueAsListInit("RegList");
 147       ListInit *ShadowRegList = Action->getValueAsListInit("ShadowRegList");
 148       if (!ShadowRegList->empty() && ShadowRegList->size() != RegList->size())
 149         PrintFatalError(Action->getLoc(),
 150                         "Invalid length of list of shadowed registers");
 151
 152       if (RegList->size() == 1) {
 153         O << IndentStr << "if (unsigned Reg = State.AllocateReg(";
 154         O << getQualifiedName(RegList->getElementAsRecord(0));
 155         O << ", " << getQualifiedName(ShadowRegList->getElementAsRecord(0));
 156         O << ")) {\n";
 157       } else {
 158         unsigned RegListNumber = ++Counter;
 159         unsigned ShadowRegListNumber = ++Counter;
 160
 161         O << IndentStr << "static const MCPhysReg RegList" << RegListNumber
 162           << "[] = {\n";
 163         O << IndentStr << "  ";
 164         ListSeparator LS;
 165         for (unsigned i = 0, e = RegList->size(); i != e; ++i)
 166           O << LS << getQualifiedName(RegList->getElementAsRecord(i));
 167         O << "\n" << IndentStr << "};\n";
 168
 169         O << IndentStr << "static const MCPhysReg RegList"
 170           << ShadowRegListNumber << "[] = {\n";
 171         O << IndentStr << "  ";
 172         ListSeparator LSS;
 173         for (unsigned i = 0, e = ShadowRegList->size(); i != e; ++i)
 174           O << LSS << getQualifiedName(ShadowRegList->getElementAsRecord(i));
 175         O << "\n" << IndentStr << "};\n";
 176
 177         O << IndentStr << "if (unsigned Reg = State.AllocateReg(RegList"
 178           << RegListNumber << ", " << "RegList" << ShadowRegListNumber
 179           << ")) {\n";
 180       }
 181       O << IndentStr << "  State.addLoc(CCValAssign::getReg(ValNo, ValVT, "
 182         << "Reg, LocVT, LocInfo));\n";
 183       O << IndentStr << "  return false;\n";
 184       O << IndentStr << "}\n";
 185     } else if (Action->isSubClassOf("CCAssignToStack")) {
 186       int Size = Action->getValueAsInt("Size");
 187       int Align = Action->getValueAsInt("Align");
 188
 189       O << IndentStr << "unsigned Offset" << ++Counter
 190         << " = State.AllocateStack(";
 191       if (Size)
 192         O << Size << ", ";
 193       else
 194         O << "\n" << IndentStr
 195           << "  State.getMachineFunction().getDataLayout()."
 196              "getTypeAllocSize(EVT(LocVT).getTypeForEVT(State.getContext())),"
 197              " ";
 198       if (Align)
 199         O << "Align(" << Align << ")";
 200       else
 201         O << "\n"
 202           << IndentStr
 203           << "  State.getMachineFunction().getDataLayout()."
 204              "getABITypeAlign(EVT(LocVT).getTypeForEVT(State.getContext()"
 205              "))";
 206       O << ");\n" << IndentStr
 207         << "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
 208         << Counter << ", LocVT, LocInfo));\n";
 209       O << IndentStr << "return false;\n";
 210     } else if (Action->isSubClassOf("CCAssignToStackWithShadow")) {
 211       int Size = Action->getValueAsInt("Size");
 212       int Align = Action->getValueAsInt("Align");
 213       ListInit *ShadowRegList = Action->getValueAsListInit("ShadowRegList");
 214
 215       unsigned ShadowRegListNumber = ++Counter;
 216
 217       O << IndentStr << "static const MCPhysReg ShadowRegList"
 218           << ShadowRegListNumber << "[] = {\n";
 219       O << IndentStr << "  ";
 220       ListSeparator LS;
 221       for (unsigned i = 0, e = ShadowRegList->size(); i != e; ++i)
 222         O << LS << getQualifiedName(ShadowRegList->getElementAsRecord(i));
 223       O << "\n" << IndentStr << "};\n";
 224
 225       O << IndentStr << "unsigned Offset" << ++Counter
 226         << " = State.AllocateStack(" << Size << ", Align(" << Align << "), "
 227         << "ShadowRegList" << ShadowRegListNumber << ");\n";
 228       O << IndentStr << "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
 229         << Counter << ", LocVT, LocInfo));\n";
 230       O << IndentStr << "return false;\n";
 231     } else if (Action->isSubClassOf("CCPromoteToType")) {
 232       Record *DestTy = Action->getValueAsDef("DestTy");
 233       MVT::SimpleValueType DestVT = getValueType(DestTy);
 234       O << IndentStr << "LocVT = " << getEnumName(DestVT) <<";\n";
 235       if (MVT(DestVT).isFloatingPoint()) {
 236         O << IndentStr << "LocInfo = CCValAssign::FPExt;\n";
 237       } else {
 238         O << IndentStr << "if (ArgFlags.isSExt())\n"
 239           << IndentStr << "  LocInfo = CCValAssign::SExt;\n"
 240           << IndentStr << "else if (ArgFlags.isZExt())\n"
 241           << IndentStr << "  LocInfo = CCValAssign::ZExt;\n"
 242           << IndentStr << "else\n"
 243           << IndentStr << "  LocInfo = CCValAssign::AExt;\n";
 244       }
 245     } else if (Action->isSubClassOf("CCPromoteToUpperBitsInType")) {
 246       Record *DestTy = Action->getValueAsDef("DestTy");
 247       MVT::SimpleValueType DestVT = getValueType(DestTy);
 248       O << IndentStr << "LocVT = " << getEnumName(DestVT) << ";\n";
 249       if (MVT(DestVT).isFloatingPoint()) {
 250         PrintFatalError(Action->getLoc(),
 251                         "CCPromoteToUpperBitsInType does not handle floating "
 252                         "point");
 253       } else {
 254         O << IndentStr << "if (ArgFlags.isSExt())\n"
 255           << IndentStr << "  LocInfo = CCValAssign::SExtUpper;\n"
 256           << IndentStr << "else if (ArgFlags.isZExt())\n"
 257           << IndentStr << "  LocInfo = CCValAssign::ZExtUpper;\n"
 258           << IndentStr << "else\n"
 259           << IndentStr << "  LocInfo = CCValAssign::AExtUpper;\n";
 260       }
 261     } else if (Action->isSubClassOf("CCBitConvertToType")) {
 262       Record *DestTy = Action->getValueAsDef("DestTy");
 263       O << IndentStr << "LocVT = " << getEnumName(getValueType(DestTy)) <<";\n";
 264       O << IndentStr << "LocInfo = CCValAssign::BCvt;\n";
 265     } else if (Action->isSubClassOf("CCTruncToType")) {
 266       Record *DestTy = Action->getValueAsDef("DestTy");
 267       O << IndentStr << "LocVT = " << getEnumName(getValueType(DestTy)) <<";\n";
 268       O << IndentStr << "LocInfo = CCValAssign::Trunc;\n";
 269     } else if (Action->isSubClassOf("CCPassIndirect")) {
 270       Record *DestTy = Action->getValueAsDef("DestTy");
 271       O << IndentStr << "LocVT = " << getEnumName(getValueType(DestTy)) <<";\n";
 272       O << IndentStr << "LocInfo = CCValAssign::Indirect;\n";
 273     } else if (Action->isSubClassOf("CCPassByVal")) {
 274       int Size = Action->getValueAsInt("Size");
 275       int Align = Action->getValueAsInt("Align");
 276       O << IndentStr << "State.HandleByVal(ValNo, ValVT, LocVT, LocInfo, "
 277         << Size << ", Align(" << Align << "), ArgFlags);\n";
 278       O << IndentStr << "return false;\n";
 279     } else if (Action->isSubClassOf("CCCustom")) {
 280       O << IndentStr
 281         << "if (" << Action->getValueAsString("FuncName") << "(ValNo, ValVT, "
 282         << "LocVT, LocInfo, ArgFlags, State))\n";
 283       O << IndentStr << "  return false;\n";
 284     } else {
 285       errs() << *Action;
 286       PrintFatalError(Action->getLoc(), "Unknown CCAction!");
 287     }
 288   }
 289 }
 290
 291 namespace llvm {
 292
 293 void EmitCallingConv(RecordKeeper &RK, raw_ostream &OS) {
 294   emitSourceFileHeader("Calling Convention Implementation Fragment", OS);
 295   CallingConvEmitter(RK).run(OS);
 296 }
 297
 298 } // End llvm namespace