llvm/lib/CodeGen/AsmPrinter.cpp

//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
//
//                     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 file implements the AsmPrinter class.
//
//===----------------------------------------------------------------------===//

#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/Constants.h"
#include "llvm/Instruction.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;

bool AsmPrinter::doInitialization(Module &M) {
  Mang = new Mangler(M, UsesUnderscorePrefix);
  return false;
}

bool AsmPrinter::doFinalization(Module &M) {
  delete Mang; Mang = 0;
  return false;
}

void AsmPrinter::setupMachineFunction(MachineFunction &MF) {
  // What's my mangled name?
  CurrentFnName = Mang->getValueName((Value*)MF.getFunction());

}



// Print out the specified constant, without a storage class.  Only the
// constants valid in constant expressions can occur here.
void AsmPrinter::emitConstantValueOnly(const Constant *CV) {
  if (CV->isNullValue())
    O << "0";
  else if (const ConstantBool *CB = dyn_cast<ConstantBool>(CV)) {
    assert(CB == ConstantBool::True);
    O << "1";
  } else if (const ConstantSInt *CI = dyn_cast<ConstantSInt>(CV))
    if (((CI->getValue() << 32) >> 32) == CI->getValue())
      O << CI->getValue();
    else
      O << (unsigned long long)CI->getValue();
  else if (const ConstantUInt *CI = dyn_cast<ConstantUInt>(CV))
    O << CI->getValue();
  else if (isa<GlobalValue>((Value*)CV))
    // This is a constant address for a global variable or function.  Use the
    // name of the variable or function as the address value.
    O << Mang->getValueName(CV);
  else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
    const TargetData &TD = TM.getTargetData();
    switch(CE->getOpcode()) {
    case Instruction::GetElementPtr: {
      // generate a symbolic expression for the byte address
      const Constant *ptrVal = CE->getOperand(0);
      std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
      if (unsigned Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
        O << "(";
        emitConstantValueOnly(ptrVal);
        O << ") + " << Offset;
      } else {
        emitConstantValueOnly(ptrVal);
      }
      break;
    }
    case Instruction::Cast: {
      // Support only non-converting or widening casts for now, that is, ones
      // that do not involve a change in value.  This assertion is really gross,
      // and may not even be a complete check.
      Constant *Op = CE->getOperand(0);
      const Type *OpTy = Op->getType(), *Ty = CE->getType();

      // Remember, kids, pointers can be losslessly converted back and forth
      // into 32-bit or wider integers, regardless of signedness. :-P
      assert(((isa<PointerType>(OpTy)
               && (Ty == Type::LongTy || Ty == Type::ULongTy
                   || Ty == Type::IntTy || Ty == Type::UIntTy))
              || (isa<PointerType>(Ty)
                  && (OpTy == Type::LongTy || OpTy == Type::ULongTy
                      || OpTy == Type::IntTy || OpTy == Type::UIntTy))
              || (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy))
                   && OpTy->isLosslesslyConvertibleTo(Ty))))
             && "FIXME: Don't yet support this kind of constant cast expr");
      O << "(";
      emitConstantValueOnly(Op);
      O << ")";
      break;
    }
    case Instruction::Add:
      O << "(";
      emitConstantValueOnly(CE->getOperand(0));
      O << ") + (";
      emitConstantValueOnly(CE->getOperand(1));
      O << ")";
      break;
    default:
      assert(0 && "Unsupported operator!");
    }
  } else {
    assert(0 && "Unknown constant value!");
  }
}