CodeEmitterGen.cpp revision 1cb65f2d6202bbfcea0a764ab1356cb574ef4d20 
1#include "Record.h"
2#include "CodeEmitterGen.h"
3
4void CodeEmitterGen::createEmitter(std::ostream &o) {
5  std::vector<Record*> Insts;
6
7  const std::map<std::string, Record*> &Defs = Records.getDefs();
8  Record *Inst = Records.getClass("Instruction");
9  assert(Inst && "Couldn't find Instruction class!");
10
11  for (std::map<std::string, Record*>::const_iterator I = Defs.begin(),
12	 E = Defs.end(); I != E; ++I)
13    if (I->second->isSubClassOf(Inst))
14      Insts.push_back(I->second);
15
16  std::string Namespace = "V9::";
17  std::string ClassName = "SparcV9CodeEmitter::";
18
19  //const std::string &Namespace = Inst->getValue("Namespace")->getName();
20  o << "unsigned " << ClassName
21    << "getBinaryCodeForInstr(MachineInstr &MI) {\n"
22    << "  unsigned Value = 0;\n"
23    << "  DEBUG(std::cerr << MI);\n"
24    << "  switch (MI.getOpcode()) {\n";
25  for (std::vector<Record*>::iterator I = Insts.begin(), E = Insts.end();
26       I != E; ++I)
27  {
28    Record *R = *I;
29    o << "    case " << Namespace << R->getName() << ": {\n"
30      << "      DEBUG(std::cerr << \"Emitting " << R->getName() << "\\n\");\n";
31
32    const RecordVal *InstVal = R->getValue("Inst");
33    Init *InitVal = InstVal->getValue();
34
35    assert(dynamic_cast<BitsInit*>(InitVal) &&
36           "Can only handle undefined bits<> types!");
37    BitsInit *BI = (BitsInit*)InitVal;
38
39    unsigned Value = 0;
40    const std::vector<RecordVal> &Vals = R->getValues();
41
42    o << "      // prefilling: ";
43    // Start by filling in fixed values...
44    for (unsigned i = 0, e = BI->getNumBits(); i != e; ++i) {
45      if (BitInit *B = dynamic_cast<BitInit*>(BI->getBit(e-i-1))) {
46        Value |= B->getValue() << (e-i-1);
47        o << B->getValue();
48      } else {
49        o << "0";
50      }
51    }
52    o << "\n";
53
54    o << "      // " << *InstVal << "\n";
55    o << "      Value = " << Value << "U;\n\n";
56
57    // Loop over all of the fields in the instruction adding in any
58    // contributions to this value (due to bit references).
59    //
60    unsigned op = 0;
61    std::map<const std::string,unsigned> OpOrder;
62    for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
63      if (Vals[i].getName() != "Inst" &&
64          !Vals[i].getValue()->isComplete() &&
65          /* ignore annul and predict bits since no one sets them yet */
66          Vals[i].getName() != "annul" &&
67          Vals[i].getName() != "predict")
68      {
69        o << "      // op" << op << ": " << Vals[i].getName() << "\n"
70          << "      int64_t op" << op
71          <<" = getMachineOpValue(MI, MI.getOperand("<<op<<"));\n";
72        //<< "      MachineOperand &op" << op <<" = MI.getOperand("<<op<<");\n";
73        OpOrder[Vals[i].getName()] = op++;
74      }
75    }
76
77    unsigned Offset = 31;
78    for (int f = Vals.size()-1; f >= 0; --f) {
79      if (Vals[f].getPrefix()) {
80        BitsInit *FieldInitializer = (BitsInit*)Vals[f].getValue();
81
82        // Scan through the field looking for bit initializers of the current
83        // variable...
84        for (int i = FieldInitializer->getNumBits()-1; i >= 0; --i) {
85          if (BitInit *BI=dynamic_cast<BitInit*>(FieldInitializer->getBit(i))){
86            --Offset;
87          } else if (UnsetInit *UI =
88                     dynamic_cast<UnsetInit*>(FieldInitializer->getBit(i))) {
89            --Offset;
90          } else if (VarBitInit *VBI =
91                     dynamic_cast<VarBitInit*>(FieldInitializer->getBit(i))) {
92            TypedInit *TI = VBI->getVariable();
93            if (VarInit *VI = dynamic_cast<VarInit*>(TI)) {
94              o << "      Value |= getValueBit(op" << OpOrder[VI->getName()]
95                << ", " << VBI->getBitNum()
96                << ")" << " << " << Offset << ";\n";
97              --Offset;
98            } else if (FieldInit *FI = dynamic_cast<FieldInit*>(TI)) {
99              // FIXME: implement this!
100              o << "FIELD INIT not implemented yet!\n";
101            } else {
102              o << "Error: UNIMPLEMENTED\n";
103            }
104          }
105        }
106      } else {
107        // ignore annul and predict bits since no one sets them yet
108        if (Vals[f].getName() == "annul" || Vals[f].getName() == "predict")
109          --Offset;
110      }
111    }
112
113    o << "      break;\n"
114      << "    }\n";
115  }
116  o << "  default:\n"
117    << "    DEBUG(std::cerr << \"Not supported instr: \" << MI << \"\\n\");\n"
118    << "    abort();\n"
119    << "  }\n"
120    << "  return Value;\n"
121    << "}\n";
122}
123