path: root/utils/TableGen/CodeGenRegisters.cpp

//===- CodeGenRegisters.cpp - Register and RegisterClass Info -------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines structures to encapsulate information gleaned from the
// target register and register class definitions.
//
//===----------------------------------------------------------------------===//

#include "CodeGenRegisters.h"
#include "CodeGenTarget.h"
#include "llvm/TableGen/Error.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringExtras.h"

using namespace llvm;

//===----------------------------------------------------------------------===//
//                             CodeGenSubRegIndex
//===----------------------------------------------------------------------===//

CodeGenSubRegIndex::CodeGenSubRegIndex(Record *R, unsigned Enum)
  : TheDef(R),
    EnumValue(Enum)
{}

std::string CodeGenSubRegIndex::getNamespace() const {
  if (TheDef->getValue("Namespace"))
    return TheDef->getValueAsString("Namespace");
  else
    return "";
}

const std::string &CodeGenSubRegIndex::getName() const {
  return TheDef->getName();
}

std::string CodeGenSubRegIndex::getQualifiedName() const {
  std::string N = getNamespace();
  if (!N.empty())
    N += "::";
  N += getName();
  return N;
}

void CodeGenSubRegIndex::updateComponents(CodeGenRegBank &RegBank) {
  std::vector<Record*> Comps = TheDef->getValueAsListOfDefs("ComposedOf");
  if (Comps.empty())
    return;
  if (Comps.size() != 2)
    throw TGError(TheDef->getLoc(), "ComposedOf must have exactly two entries");
  CodeGenSubRegIndex *A = RegBank.getSubRegIdx(Comps[0]);
  CodeGenSubRegIndex *B = RegBank.getSubRegIdx(Comps[1]);
  CodeGenSubRegIndex *X = A->addComposite(B, this);
  if (X)
    throw TGError(TheDef->getLoc(), "Ambiguous ComposedOf entries");
}

void CodeGenSubRegIndex::cleanComposites() {
  // Clean out redundant mappings of the form this+X -> X.
  for (CompMap::iterator i = Composed.begin(), e = Composed.end(); i != e;) {
    CompMap::iterator j = i;
    ++i;
    if (j->first == j->second)
      Composed.erase(j);
  }
}

//===----------------------------------------------------------------------===//
//                              CodeGenRegister
//===----------------------------------------------------------------------===//

CodeGenRegister::CodeGenRegister(Record *R, unsigned Enum)
  : TheDef(R),
    EnumValue(Enum),
    CostPerUse(R->getValueAsInt("CostPerUse")),
    CoveredBySubRegs(R->getValueAsBit("CoveredBySubRegs")),
    SubRegsComplete(false)
{}

const std::string &CodeGenRegister::getName() const {
  return TheDef->getName();
}

const CodeGenRegister::SubRegMap &
CodeGenRegister::getSubRegs(CodeGenRegBank &RegBank) {
  // Only compute this map once.
  if (SubRegsComplete)
    return SubRegs;
  SubRegsComplete = true;

  std::vector<Record*> SubList = TheDef->getValueAsListOfDefs("SubRegs");
  std::vector<Record*> IdxList = TheDef->getValueAsListOfDefs("SubRegIndices");
  if (SubList.size() != IdxList.size())
    throw TGError(TheD