utils/TableGen/AsmWriterEmitter.cpp

//===- AsmWriterEmitter.cpp - Generate an assembly writer -----------------===//
// 
//                     The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
// 
//===----------------------------------------------------------------------===//
//
// This tablegen backend is emits an assembly printer for the current target.
// Note that this is currently fairly skeletal, but will grow over time.
//
//===----------------------------------------------------------------------===//

#include "AsmWriterEmitter.h"
#include "CodeGenTarget.h"
#include <ostream>
using namespace llvm;

void AsmWriterEmitter::run(std::ostream &O) {
  EmitSourceFileHeader("Assembly Writer Source Fragment", O);

  CodeGenTarget Target;
  O <<
  "/// printInstruction - This method is automatically generated by tablegen\n"
  "/// from the instruction set description.  This method returns true if the\n"
  "/// machine instruction was sufficiently described to print it, otherwise\n"
  "/// it returns false.\n"
    "bool " << Target.getName()
            << "AsmPrinter::printInstruction(const MachineInstr *MI) {\n";
  O << "  switch (MI->getOpcode()) {\n"
       "  default: return false;\n";

  std::string Namespace = Target.inst_begin()->second.Namespace;

  for (CodeGenTarget::inst_iterator I = Target.inst_begin(),
         E = Target.inst_end(); I != E; ++I)
    if (!I->second.AsmString.empty()) {
      const std::string &AsmString = I->second.AsmString;
      O << "  case " << Namespace << "::" << I->first << ": O << \""
        << AsmString << "\" << '\\n'; break;\n";
    }

  O << "  }\n"
       "  return true;\n"
       "}\n";
  EmitSourceFileTail(O);
}