CallingConvEmitter.cpp revision e3ef744d3e3557ee286d2ed3bf8306e5fbbd1ac4 
1//===- CallingConvEmitter.cpp - Generate calling conventions --------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by Chris Lattner and is distributed under
6// the University of Illinois Open Source 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 "CallingConvEmitter.h"
16#include "Record.h"
17#include "CodeGenTarget.h"
18using namespace llvm;
19
20void CallingConvEmitter::run(std::ostream &O) {
21  EmitSourceFileHeader("Calling Convention Implementation Fragment", O);
22
23  std::vector<Record*> CCs = Records.getAllDerivedDefinitions("CallingConv");
24
25  // Emit prototypes for all of the CC's so that they can forward ref each
26  // other.
27  for (unsigned i = 0, e = CCs.size(); i != e; ++i) {
28    O << "static bool " << CCs[i]->getName()
29      << "(unsigned ValNo, MVT::ValueType ValVT,\n"
30      << std::string(CCs[i]->getName().size()+13, ' ')
31      << "MVT::ValueType LocVT, CCValAssign::LocInfo LocInfo,\n"
32      << std::string(CCs[i]->getName().size()+13, ' ')
33      << "unsigned ArgFlags, CCState &State);\n";
34  }
35
36  // Emit each calling convention description in full.
37  for (unsigned i = 0, e = CCs.size(); i != e; ++i)
38    EmitCallingConv(CCs[i], O);
39}
40
41
42void CallingConvEmitter::EmitCallingConv(Record *CC, std::ostream &O) {
43  ListInit *CCActions = CC->getValueAsListInit("Actions");
44  Counter = 0;
45
46  O << "\n\nstatic bool " << CC->getName()
47    << "(unsigned ValNo, MVT::ValueType ValVT,\n"
48    << std::string(CC->getName().size()+13, ' ')
49    << "MVT::ValueType LocVT, CCValAssign::LocInfo LocInfo,\n"
50    << std::string(CC->getName().size()+13, ' ')
51    << "unsigned ArgFlags, CCState &State) {\n";
52  // Emit all of the actions, in order.
53  for (unsigned i = 0, e = CCActions->getSize(); i != e; ++i) {
54    O << "\n";
55    EmitAction(CCActions->getElementAsRecord(i), 2, O);
56  }
57
58  O << "\n  return true;  // CC didn't match.\n";
59  O << "}\n";
60}
61
62void CallingConvEmitter::EmitAction(Record *Action,
63                                    unsigned Indent, std::ostream &O) {
64  std::string IndentStr = std::string(Indent, ' ');
65
66  if (Action->isSubClassOf("CCPredicateAction")) {
67    O << IndentStr << "if (";
68
69    if (Action->isSubClassOf("CCIfType")) {
70      ListInit *VTs = Action->getValueAsListInit("VTs");
71      for (unsigned i = 0, e = VTs->getSize(); i != e; ++i) {
72        Record *VT = VTs->getElementAsRecord(i);
73        if (i != 0) O << " ||\n    " << IndentStr;
74        O << "LocVT == " << getEnumName(getValueType(VT));
75      }
76
77    } else if (Action->isSubClassOf("CCIf")) {
78      O << Action->getValueAsString("Predicate");
79    } else {
80      Action->dump();
81      throw "Unknown CCPredicateAction!";
82    }
83
84    O << ") {\n";
85    EmitAction(Action->getValueAsDef("SubAction"), Indent+2, O);
86    O << IndentStr << "}\n";
87  } else {
88    if (Action->isSubClassOf("CCDelegateTo")) {
89      Record *CC = Action->getValueAsDef("CC");
90      O << IndentStr << "if (!" << CC->getName()
91        << "(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State))\n"
92        << IndentStr << "  return false;\n";
93    } else if (Action->isSubClassOf("CCAssignToReg")) {
94      ListInit *RegList = Action->getValueAsListInit("RegList");
95      if (RegList->getSize() == 1) {
96        O << IndentStr << "if (unsigned Reg = State.AllocateReg(";
97        O << getQualifiedName(RegList->getElementAsRecord(0)) << ")) {\n";
98      } else {
99        O << IndentStr << "static const unsigned RegList" << ++Counter
100          << "[] = {\n";
101        O << IndentStr << "  ";
102        for (unsigned i = 0, e = RegList->getSize(); i != e; ++i) {
103          if (i != 0) O << ", ";
104          O << getQualifiedName(RegList->getElementAsRecord(i));
105        }
106        O << "\n" << IndentStr << "};\n";
107        O << IndentStr << "if (unsigned Reg = State.AllocateReg(RegList"
108          << Counter << ", " << RegList->getSize() << ")) {\n";
109      }
110      O << IndentStr << "  State.addLoc(CCValAssign::getReg(ValNo, ValVT, "
111        << "Reg, LocVT, LocInfo));\n";
112      O << IndentStr << "  return false;\n";
113      O << IndentStr << "}\n";
114    } else if (Action->isSubClassOf("CCAssignToStack")) {
115      int Size = Action->getValueAsInt("Size");
116      int Align = Action->getValueAsInt("Align");
117
118      O << IndentStr << "unsigned Offset" << ++Counter
119        << " = State.AllocateStack(" << Size << ", " << Align << ");\n";
120      O << IndentStr << "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
121        << Counter << ", LocVT, LocInfo));\n";
122      O << IndentStr << "return false;\n";
123    } else if (Action->isSubClassOf("CCAssignToStackABISizeAlign")) {
124      O << IndentStr << "unsigned Offset" << ++Counter
125        << " = State.AllocateStack(State.getTarget().getTargetData()"
126           "->getABITypeSize(MVT::getTypeForValueType(LocVT)),\n";
127      O << IndentStr << "       State.getTarget().getTargetData()"
128           "->getABITypeAlignment(MVT::getTypeForValueType(LocVT)));\n";
129      O << IndentStr << "State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset"
130        << Counter << ", LocVT, LocInfo));\n";
131      O << IndentStr << "return false;\n";
132    } else if (Action->isSubClassOf("CCPromoteToType")) {
133      Record *DestTy = Action->getValueAsDef("DestTy");
134      O << IndentStr << "LocVT = " << getEnumName(getValueType(DestTy)) <<";\n";
135      O << IndentStr << "if (ArgFlags & ISD::ParamFlags::SExt)\n"
136        << IndentStr << IndentStr << "LocInfo = CCValAssign::SExt;\n"
137        << IndentStr << "else if (ArgFlags & ISD::ParamFlags::ZExt)\n"
138        << IndentStr << IndentStr << "LocInfo = CCValAssign::ZExt;\n"
139        << IndentStr << "else\n"
140        << IndentStr << IndentStr << "LocInfo = CCValAssign::AExt;\n";
141    } else if (Action->isSubClassOf("CCStructAssign")) {
142      O << IndentStr <<
143          "State.HandleStruct(ValNo, ValVT, LocVT, LocInfo, ArgFlags);\n";
144      O << IndentStr << "return false;\n";
145    } else {
146      Action->dump();
147      throw "Unknown CCAction!";
148    }
149  }
150}
151