//===-- llvm/CodeGen/MachineFunctionInfo.h ----------------------*- C++ -*-===//
// 
// This class keeps track of information about the stack frame and about the
// per-function constant pool.
//   
//===----------------------------------------------------------------------===//

#ifndef LLVM_CODEGEN_MACHINEFUNCTIONINFO_H
#define LLVM_CODEGEN_MACHINEFUNCTIONINFO_H

#include "Support/HashExtras.h"
#include "Support/hash_set"
class MachineFunction;
class Value;
class Constant;
class Type;

class MachineFunctionInfo {
  hash_set<const Constant*> constantsForConstPool;
  hash_map<const Value*, int> offsets;
  unsigned	staticStackSize;
  unsigned	automaticVarsSize;
  unsigned	regSpillsSize;
  unsigned	maxOptionalArgsSize;
  unsigned	maxOptionalNumArgs;
  unsigned	currentTmpValuesSize;
  unsigned	maxTmpValuesSize;
  bool          compiledAsLeaf;
  bool          spillsAreaFrozen;
  bool          automaticVarsAreaFrozen;

  MachineFunction &MF;
public:
  MachineFunctionInfo(MachineFunction &mf) : MF(mf) {
    staticStackSize = automaticVarsSize = regSpillsSize = 0;
    maxOptionalArgsSize = maxOptionalNumArgs = currentTmpValuesSize = 0;
    maxTmpValuesSize = 0;
    compiledAsLeaf = spillsAreaFrozen = automaticVarsAreaFrozen = false;
  }

  /// CalculateArgSize - Call this method to fill in the maxOptionalArgsSize &
  /// staticStackSize fields...
  ///
  void CalculateArgSize();

  //
  // Accessors for global information about generated code for a method.
  // 
  bool     isCompiledAsLeafMethod() const { return compiledAsLeaf; }
  unsigned getStaticStackSize()     const { return staticStackSize; }
  unsigned getAutomaticVarsSize()   const { return automaticVarsSize; }
  unsigned getRegSpillsSize()       const { return regSpillsSize; }
  unsigned getMaxOptionalArgsSize() const { return maxOptionalArgsSize;}
  unsigned getMaxOptionalNumArgs()  const { return maxOptionalNumArgs;}
  const hash_set<const Constant*> &getConstantPoolValues() const {
    return constantsForConstPool;
  }
  
  //
  // Modifiers used during code generation
  // 
  void            initializeFrameLayout    ();
  
  void            addToConstantPool        (const Constant* constVal) {
    constantsForConstPool.insert(constVal);
  }
  
  void markAsLeafMethod() { compiledAsLeaf = true; }
  
  int             computeOffsetforLocalVar (const Value*  local,
                                            unsigned& getPaddedSize,
                                            unsigned  sizeToUse = 0);
  int             allocateLocalVar         (const Value* local,
                                            unsigned sizeToUse = 0);
  
  int             allocateSpilledValue     (const Type* type);
  int             pushTempValue            (unsigned size);
  void            popAllTempValues         ();
  
  void            freezeSpillsArea         () { spillsAreaFrozen = true; } 
  void            freezeAutomaticVarsArea  () { automaticVarsAreaFrozen=true; }
  
  int             getOffset                (const Value* val) const;
  
private:
  void incrementAutomaticVarsSize(int incr) {
    automaticVarsSize+= incr;
    staticStackSize += incr;
  }
  void incrementRegSpillsSize(int incr) {
    regSpillsSize+= incr;
    staticStackSize += incr;
  }
  void incrementTmpAreaSize(int incr) {
    currentTmpValuesSize += incr;
    if (maxTmpValuesSize < currentTmpValuesSize)
      {
        staticStackSize += currentTmpValuesSize - maxTmpValuesSize;
        maxTmpValuesSize = currentTmpValuesSize;
      }
  }
  void resetTmpAreaSize() {
    currentTmpValuesSize = 0;
  }
  int allocateOptionalArg(const Type* type);
};

#endif