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/Record.h"
17#include "llvm/TableGen/TableGenBackend.h"
18#include <cassert>
19using namespace llvm;
20
21namespace {
22class CallingConvEmitter {
23  RecordKeeper &Records;
24public:
25  explicit CallingConvEmitter(RecordKeeper &R) : Records(R) {}
26
27  void run(raw_ostream &o);
28
29private:
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
36void CallingConvEmitter::run(raw_ostream &O) {
37
38  std::vector<Record*> CCs = Records.getAllDerivedDefinitions("CallingConv");
39
40  // Emit prototypes for all of the CC's so that they can forward ref each
41  // other.
42  for (unsigned i = 0, e = CCs.size(); i != e; ++i) {
43    O << "static bool " << CCs[i]->getName()
44      << "(unsigned ValNo, MVT ValVT,\n"
45      << std::string(CCs[i]->getName().size()+13, ' ')
46      << "MVT LocVT, CCValAssign::LocInfo LocInfo,\n"
47      << std::string(CCs[i]->getName().size()+13, ' ')
48      << "ISD::ArgFlagsTy ArgFlags, CCState &State);\n";
49  }
50
51  // Emit each calling convention description in full.
52  for (unsigned i = 0, e = CCs.size(); i != e; ++i)
53    EmitCallingConv(CCs[i], O);
54}
55
56
57void CallingConvEmitter::EmitCallingConv(Record *CC, raw_ostream &O) {
58  ListInit *CCActions = CC->getValueAsListInit("Actions");
59  Counter = 0;
60
61  O << "\n\nstatic bool " << CC->getName()
62    << "(unsigned ValNo, MVT ValVT,\n"
63    << std::string(CC->getName().size()+13, ' ')
64    << "MVT LocVT, CCValAssign::LocInfo LocInfo,\n"
65    << std::string(CC->getName().size()+13, ' ')
66    << "ISD::ArgFlagsTy ArgFlags, CCState &State) {\n";
67  // Emit all of the actions, in order.
68  for (unsigned i = 0, e = CCActions->getSize(); i != e; ++i) {
69    O << "\n";
70    EmitAction(CCActions->getElementAsRecord(i), 2, O);
71  }
72
73  O << "\n  return true;  // CC didn't match.\n";
74  O << "}\n";
75}
76
77void CallingConvEmitter::EmitAction(Record *Action,
78                                    unsigned Indent, raw_ostream &O) {
79  std::string IndentStr = std::string(Indent, ' ');
80
81  if (Action->isSubClassOf("CCPredicateAction")) {
82    O << IndentStr << "if (";
83
84    if (Action->isSubClassOf("CCIfType")) {
85      ListInit *VTs = Action->getValueAsListInit("VTs");
86      for (unsigned i = 0, e = VTs->getSize(); i != e; ++i) {
87        Record *VT = VTs->getElementAsRecord(i);
88        if (i != 0) O << " ||\n    " << IndentStr;
89        O << "LocVT == " << getEnumName(getValueType(VT));
90      }
91
92    } else if (Action->isSubClassOf("CCIf")) {
93      O << Action->getValueAsString("Predicate");
94    } else {
95      Action->dump();
96      throw "Unknown CCPredicateAction!";
97    }
98
99    O << ") {\n";
100    EmitAction(Action->getValueAsDef("SubAction"), Indent+2, O);
101    O << IndentStr << "}\n";
102  } else {
103    if (Action->isSubClassOf("CCDelegateTo")) {
104      Record *CC = Action->getValueAsDef("CC");
105      O << IndentStr << "if (!" << CC->getName()
106        << "(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State))\n"
107        << IndentStr << "  return false;\n";
108    } else if (Action->isSubClassOf("CCAssignToReg")) {
109      ListInit *RegList = Action->getValueAsListInit("RegList");
110      if (RegList->getSize() == 1) {
111        O << IndentStr << "if (unsigned Reg = State.AllocateReg(";
112        O << getQualifiedName(RegList->getElementAsRecord(0)) << ")) {\n";
113      } else {
114        O << IndentStr << "static const uint16_t RegList" << ++Counter
115          << "[] = {\n";
116        O << IndentStr << "  ";
117        for (unsigned i = 0, e = RegList->getSize(); i != e; ++i) {
118          if (i != 0) O << ", ";
119          O << getQualifiedName(RegList->getElementAsRecord(i));
120        }
121        O << "\n" << IndentStr << "};\n";
122        O << IndentStr << "if (unsigned Reg = State.AllocateReg(RegList"
123          << Counter << ", " << RegList->getSize() << ")) {\n";
124      }
125      O << IndentStr << "  State.addLoc(CCValAssign::getReg(ValNo, ValVT, "
126        << "Reg, LocVT, LocInfo));\n";
127      O << IndentStr << "  return false;\n";
128      O << IndentStr << "}\n";
129    } else if (Action->isSubClassOf("CCAssignToRegWithShadow")) {
130      ListInit *RegList = Action->getValueAsListInit("RegList");
131      ListInit *ShadowRegList = Action->getValueAsListInit("ShadowRegList");
132      if (ShadowRegList->getSize() >0 &&
133          ShadowRegList->getSize() != RegList->getSize())
134        throw "Invalid length of list of shadowed registers";
135
136      if (RegList->getSize() == 1) {
137        O << IndentStr << "if (unsigned Reg = State.AllocateReg(";
138        O << getQualifiedName(RegList->getElementAsRecord(0));
139        O << ", " << getQualifiedName(ShadowRegList->getElementAsRecord(0));
140        O << ")) {\n";
141      } else {
142        unsigned RegListNumber = ++Counter;
143        unsigned ShadowRegListNumber = ++Counter;
144
145        O << IndentStr << "static const uint16_t RegList" << RegListNumber
146          << "[] = {\n";
147        O << IndentStr << "  ";
148        for (unsigned i = 0, e = RegList->getSize(); i != e; ++i) {
149          if (i != 0) O << ", ";
150          O << getQualifiedName(RegList->getElementAsRecord(i));
151        }
152        O << "\n" << IndentStr << "};\n";
153
154        O << IndentStr << "static const uint16_t RegList"
155          << ShadowRegListNumber << "[] = {\n";
156        O << IndentStr << "  ";
157        for (unsigned i = 0, e = ShadowRegList->getSize(); i != e; ++i) {
158          if (i != 0) O << ", ";
159          O << getQualifiedName(ShadowRegList->getElementAsRecord(i));
160        }
161        O << "\n" << IndentStr << "};\n";
162
163        O << IndentStr << "if (unsigned Reg = State.AllocateReg(RegList"
164          << RegListNumber << ", " << "RegList" << ShadowRegListNumber
165          << ", " << RegList->getSize() << ")) {\n";
166      }
167      O << IndentStr << "  State.addLoc(CCValAssign::getReg(ValNo, ValVT, "
168        << "Reg, LocVT, LocInfo));\n";
169      O << IndentStr << "  return false;\n";
170      O << IndentStr << "}\n";
171    } else if (Action->isSubClassOf("CCAssignToStack")) {
172      int Size = Action->getValueAsInt("Size");
173      int Align = Action->getValueAsInt("Align");
174
175      O << IndentStr << "unsigned Offset" << ++Counter
176        << " = State.AllocateStack(";
177      if (Size)
178        O << Size << ", ";
179      else
180        O << "\n" << IndentStr << "  State.getTarget().getTargetData()"
181          "->getTypeAllocSize(EVT(LocVT).getTypeForEVT(State.getContext())), ";
182      if (Align)
183        O << Align;
184      else
185        O << "\n" << IndentStr << "  State.getTarget().getTargetData()"
186          "->getABITypeAlignment(EVT(LocVT).getTypeForEVT(State.getContext()))";
187      if (Action->isSubClassOf("CCAssignToStackWithShadow"))
188        O << ", " << getQualifiedName(Action->getValueAsDef("ShadowReg"));
189      O << ");\n" << IndentStr
190        << "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
191        << Counter << ", LocVT, LocInfo));\n";
192      O << IndentStr << "return false;\n";
193    } else if (Action->isSubClassOf("CCPromoteToType")) {
194      Record *DestTy = Action->getValueAsDef("DestTy");
195      O << IndentStr << "LocVT = " << getEnumName(getValueType(DestTy)) <<";\n";
196      O << IndentStr << "if (ArgFlags.isSExt())\n"
197        << IndentStr << IndentStr << "LocInfo = CCValAssign::SExt;\n"
198        << IndentStr << "else if (ArgFlags.isZExt())\n"
199        << IndentStr << IndentStr << "LocInfo = CCValAssign::ZExt;\n"
200        << IndentStr << "else\n"
201        << IndentStr << IndentStr << "LocInfo = CCValAssign::AExt;\n";
202    } else if (Action->isSubClassOf("CCBitConvertToType")) {
203      Record *DestTy = Action->getValueAsDef("DestTy");
204      O << IndentStr << "LocVT = " << getEnumName(getValueType(DestTy)) <<";\n";
205      O << IndentStr << "LocInfo = CCValAssign::BCvt;\n";
206    } else if (Action->isSubClassOf("CCPassIndirect")) {
207      Record *DestTy = Action->getValueAsDef("DestTy");
208      O << IndentStr << "LocVT = " << getEnumName(getValueType(DestTy)) <<";\n";
209      O << IndentStr << "LocInfo = CCValAssign::Indirect;\n";
210    } else if (Action->isSubClassOf("CCPassByVal")) {
211      int Size = Action->getValueAsInt("Size");
212      int Align = Action->getValueAsInt("Align");
213      O << IndentStr
214        << "State.HandleByVal(ValNo, ValVT, LocVT, LocInfo, "
215        << Size << ", " << Align << ", ArgFlags);\n";
216      O << IndentStr << "return false;\n";
217    } else if (Action->isSubClassOf("CCCustom")) {
218      O << IndentStr
219        << "if (" << Action->getValueAsString("FuncName") << "(ValNo, ValVT, "
220        << "LocVT, LocInfo, ArgFlags, State))\n";
221      O << IndentStr << IndentStr << "return false;\n";
222    } else {
223      Action->dump();
224      throw "Unknown CCAction!";
225    }
226  }
227}
228
229namespace llvm {
230
231void EmitCallingConv(RecordKeeper &RK, raw_ostream &OS) {
232  emitSourceFileHeader("Calling Convention Implementation Fragment", OS);
233  CallingConvEmitter(RK).run(OS);
234}
235
236} // End llvm namespace
237