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