path: root/lib/CodeGen/RegAlloc/PhyRegAlloc.cpp

// $Id$
//***************************************************************************
// File:
//	PhyRegAlloc.cpp
// 
// Purpose:
//      Register allocation for LLVM.
//	
// History:
//	9/10/01	 -  Ruchira Sasanka - created.
//**************************************************************************/

#include "llvm/CodeGen/PhyRegAlloc.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineCodeForMethod.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/MachineFrameInfo.h"
#include <iostream>
#include <math.h>
using std::cerr;


// ***TODO: There are several places we add instructions. Validate the order
//          of adding these instructions.



cl::Enum<RegAllocDebugLevel_t> DEBUG_RA("dregalloc", cl::NoFlags,
  "enable register allocation debugging information",
  clEnumValN(RA_DEBUG_None   , "n", "disable debug output"),
  clEnumValN(RA_DEBUG_Normal , "y", "enable debug output"),
  clEnumValN(RA_DEBUG_Verbose, "v", "enable extra debug output"), 0);


//----------------------------------------------------------------------------
// Constructor: Init local composite objects and create register classes.
//----------------------------------------------------------------------------
PhyRegAlloc::PhyRegAlloc(Method *M, 
			 const TargetMachine& tm, 
			 MethodLiveVarInfo *const Lvi) 
                       :  TM(tm), Meth(M),
                          mcInfo(MachineCodeForMethod::get(M)),
                          LVI(Lvi), LRI(M, tm, RegClassList), 
			  MRI( tm.getRegInfo() ),
                          NumOfRegClasses(MRI.getNumOfRegClasses()),
			  LoopDepthCalc(M) {

  // create each RegisterClass and put in RegClassList
  //
  for(unsigned int rc=0; rc < NumOfRegClasses; rc++)  
    RegClassList.push_back( new RegClass(M, MRI.getMachineRegClass(rc), 
					 &ResColList) );
}


//----------------------------------------------------------------------------
// Destructor: Deletes register classes
//----------------------------------------------------------------------------
PhyRegAlloc::~PhyRegAlloc() { 
  for( unsigned int rc=0; rc < NumOfRegClasses; rc++)
    delete RegClassList[rc];
} 

//----------------------------------------------------------------------------
// This method initally creates interference graphs (one in each reg class)
// and IGNodeList (one in each IG). The actual nodes will be pushed later. 
//----------------------------------------------------------------------------
void PhyRegAlloc::createIGNodeListsAndIGs() {
  if (DEBUG_RA) cerr << "Creating LR lists ...\n";

  // hash map iterator
  LiveRangeMapType::const_iterator HMI = LRI.getLiveRangeMap()->begin();   

  // hash map end
  LiveRangeMapType::const_iterator HMIEnd = LRI.getLiveRangeMap()->end();   

  for (; HMI != HMIEnd ; ++HMI ) {
    if (HMI->first) { 
      LiveRange *L = HMI->second;   // get the LiveRange
      if (!L) {