#include "llvm/CodeGen/LiveRangeInfo.h"
-
+#include "llvm/CodeGen/RegClass.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Method.h"
+#include <iostream>
+using std::cerr;
+
+//---------------------------------------------------------------------------
+// Constructor
+//---------------------------------------------------------------------------
LiveRangeInfo::LiveRangeInfo(const Method *const M,
const TargetMachine& tm,
- vector<RegClass *> &RCL)
- : Meth(M), LiveRangeMap(),
- TM(tm), RegClassList(RCL),
- MRI( tm.getRegInfo()),
- CallRetInstrList()
+ std::vector<RegClass *> &RCL)
+ : Meth(M), LiveRangeMap(), TM(tm),
+ RegClassList(RCL), MRI(tm.getRegInfo())
{ }
+//---------------------------------------------------------------------------
+// Destructor: Deletes all LiveRanges in the LiveRangeMap
+//---------------------------------------------------------------------------
+LiveRangeInfo::~LiveRangeInfo() {
+ LiveRangeMapType::iterator MI = LiveRangeMap.begin();
+
+ for( ; MI != LiveRangeMap.end() ; ++MI) {
+ if (MI->first && MI->second) {
+ LiveRange *LR = MI->second;
+
+ // we need to be careful in deleting LiveRanges in LiveRangeMap
+ // since two/more Values in the live range map can point to the same
+ // live range. We have to make the other entries NULL when we delete
+ // a live range.
+
+ LiveRange::iterator LI = LR->begin();
+
+ for( ; LI != LR->end() ; ++LI)
+ LiveRangeMap[*LI] = 0;
+
+ delete LR;
+ }
+ }
+}
+
+
+//---------------------------------------------------------------------------
// union two live ranges into one. The 2nd LR is deleted. Used for coalescing.
// Note: the caller must make sure that L1 and L2 are distinct and both
// LRs don't have suggested colors
-
+//---------------------------------------------------------------------------
void LiveRangeInfo::unionAndUpdateLRs(LiveRange *const L1, LiveRange *L2)
{
assert( L1 != L2);
- L1->setUnion( L2 ); // add elements of L2 to L1
+ L1->setUnion( L2 ); // add elements of L2 to L1
ValueSet::iterator L2It;
for( L2It = L2->begin() ; L2It != L2->end(); ++L2It) {
//assert(( L1->getTypeID() == L2->getTypeID()) && "Merge:Different types");
- L1->add( *L2It ); // add the var in L2 to L1
- LiveRangeMap[ *L2It ] = L1; // now the elements in L2 should map to L1
+ L1->add( *L2It ); // add the var in L2 to L1
+ LiveRangeMap[ *L2It ] = L1; // now the elements in L2 should map
+ //to L1
}
if( L2->isCallInterference() )
L1->setCallInterference();
+
+ L1->addSpillCost( L2->getSpillCost() ); // add the spill costs
- delete ( L2 ); // delete L2 as it is no longer needed
+ delete L2; // delete L2 as it is no longer needed
}
-
+//---------------------------------------------------------------------------
+// Method for constructing all live ranges in a method. It creates live
+// ranges for all values defined in the instruction stream. Also, it
+// creates live ranges for all incoming arguments of the method.
+//---------------------------------------------------------------------------
void LiveRangeInfo::constructLiveRanges()
{
if( DEBUG_RA)
- cout << "Consturcting Live Ranges ..." << endl;
+ cerr << "Consturcting Live Ranges ...\n";
// first find the live ranges for all incoming args of the method since
// those LRs start from the start of the method
for( ; ArgIt != ArgList.end() ; ++ArgIt) { // for each argument
-
LiveRange * ArgRange = new LiveRange(); // creates a new LR and
const Value *const Val = (const Value *) *ArgIt;
assert( Val);
- ArgRange->add( Val ); // add the arg (def) to it
- LiveRangeMap[ Val ] = ArgRange;
+ ArgRange->add(Val); // add the arg (def) to it
+ LiveRangeMap[Val] = ArgRange;
// create a temp machine op to find the register class of value
//const MachineOperand Op(MachineOperand::MO_VirtualRegister);
if( DEBUG_RA > 1) {
- cout << " adding LiveRange for argument ";
- printValue( (const Value *) *ArgIt); cout << endl;
+ cerr << " adding LiveRange for argument ";
+ printValue((const Value *) *ArgIt); cerr << "\n";
}
}
Method::const_iterator BBI = Meth->begin(); // random iterator for BBs
-
for( ; BBI != Meth->end(); ++BBI) { // go thru BBs in random order
// Now find all LRs for machine the instructions. A new LR will be created
// get the iterator for machine instructions
const MachineCodeForBasicBlock& MIVec = (*BBI)->getMachineInstrVec();
- MachineCodeForBasicBlock::const_iterator
- MInstIterator = MIVec.begin();
+ MachineCodeForBasicBlock::const_iterator MInstIterator = MIVec.begin();
// iterate over all the machine instructions in BB
for( ; MInstIterator != MIVec.end(); MInstIterator++) {
// Now if the machine instruction is a call/return instruction,
// add it to CallRetInstrList for processing its implicit operands
- if( (TM.getInstrInfo()).isReturn( MInst->getOpCode()) ||
- (TM.getInstrInfo()).isCall( MInst->getOpCode()) )
+ if(TM.getInstrInfo().isReturn(MInst->getOpCode()) ||
+ TM.getInstrInfo().isCall(MInst->getOpCode()))
CallRetInstrList.push_back( MInst );
// iterate over MI operands to find defs
- for( MachineInstr::val_const_op_iterator OpI(MInst);!OpI.done(); ++OpI) {
-
- if( DEBUG_RA) {
+ for (MachineInstr::val_const_op_iterator OpI(MInst); !OpI.done(); ++OpI) {
+ if(DEBUG_RA) {
MachineOperand::MachineOperandType OpTyp =
OpI.getMachineOperand().getOperandType();
- if ( OpTyp == MachineOperand::MO_CCRegister) {
- cout << "\n**CC reg found. Is Def=" << OpI.isDef() << " Val:";
+ if (OpTyp == MachineOperand::MO_CCRegister) {
+ cerr << "\n**CC reg found. Is Def=" << OpI.isDef() << " Val:";
printValue( OpI.getMachineOperand().getVRegValue() );
- cout << endl;
+ cerr << "\n";
}
}
// create a new LR iff this operand is a def
if( OpI.isDef() ) {
-
const Value *const Def = *OpI;
-
// Only instruction values are accepted for live ranges here
-
if( Def->getValueType() != Value::InstructionVal ) {
- cout << "\n**%%Error: Def is not an instruction val. Def=";
- printValue( Def ); cout << endl;
+ cerr << "\n**%%Error: Def is not an instruction val. Def=";
+ printValue( Def ); cerr << "\n";
continue;
}
-
LiveRange *DefRange = LiveRangeMap[Def];
// see LR already there (because of multiple defs)
-
if( !DefRange) { // if it is not in LiveRangeMap
-
DefRange = new LiveRange(); // creates a new live range and
DefRange->add( Def ); // add the instruction (def) to it
LiveRangeMap[ Def ] = DefRange; // update the map
if( DEBUG_RA > 1) {
- cout << " creating a LR for def: ";
- printValue(Def); cout << endl;
+ cerr << " creating a LR for def: ";
+ printValue(Def); cerr << "\n";
}
// set the register class of the new live range
if(isCC && DEBUG_RA) {
- cout << "\a**created a LR for a CC reg:";
+ cerr << "\a**created a LR for a CC reg:";
printValue( OpI.getMachineOperand().getVRegValue() );
}
LiveRangeMap[ Def ] = DefRange;
if( DEBUG_RA > 1) {
- cout << " added to an existing LR for def: ";
- printValue( Def ); cout << endl;
+ cerr << " added to an existing LR for def: ";
+ printValue( Def ); cerr << "\n";
}
}
suggestRegs4CallRets();
if( DEBUG_RA)
- cout << "Initial Live Ranges constructed!" << endl;
+ cerr << "Initial Live Ranges constructed!\n";
}
-
-// Suggest colors for call and return args.
-// Also create new LRs for implicit defs
-
+//---------------------------------------------------------------------------
+// If some live ranges must be colored with specific hardware registers
+// (e.g., for outgoing call args), suggesting of colors for such live
+// ranges is done using target specific method. Those methods are called
+// from this function. The target specific methods must:
+// 1) suggest colors for call and return args.
+// 2) create new LRs for implicit defs in machine instructions
+//---------------------------------------------------------------------------
void LiveRangeInfo::suggestRegs4CallRets()
{
}
+//--------------------------------------------------------------------------
+// The following method coalesces live ranges when possible. This method
+// must be called after the interference graph has been constructed.
-void LiveRangeInfo::coalesceLRs()
-{
-
/* Algorithm:
for each BB in method
for each machine instruction (inst)
merge2IGNodes(def, op) // i.e., merge 2 LRs
*/
-
+//---------------------------------------------------------------------------
+void LiveRangeInfo::coalesceLRs()
+{
if( DEBUG_RA)
- cout << endl << "Coalscing LRs ..." << endl;
+ cerr << "\nCoalscing LRs ...\n";
Method::const_iterator BBI = Meth->begin(); // random iterator for BBs
// get the iterator for machine instructions
const MachineCodeForBasicBlock& MIVec = (*BBI)->getMachineInstrVec();
- MachineCodeForBasicBlock::const_iterator
- MInstIterator = MIVec.begin();
+ MachineCodeForBasicBlock::const_iterator MInstIterator = MIVec.begin();
// iterate over all the machine instructions in BB
for( ; MInstIterator != MIVec.end(); ++MInstIterator) {
const MachineInstr * MInst = *MInstIterator;
if( DEBUG_RA > 1) {
- cout << " *Iterating over machine instr ";
+ cerr << " *Iterating over machine instr ";
MInst->dump();
- cout << endl;
+ cerr << "\n";
}
//don't warn about labels
if (!((*UseI)->getType())->isLabelType() && DEBUG_RA) {
- cout<<" !! Warning: No LR for use "; printValue(*UseI);
- cout << endl;
+ cerr<<" !! Warning: No LR for use "; printValue(*UseI);
+ cerr << "\n";
}
continue; // ignore and continue
}
} // for all BBs
if( DEBUG_RA)
- cout << endl << "Coalscing Done!" << endl;
+ cerr << "\nCoalscing Done!\n";
}
void LiveRangeInfo::printLiveRanges()
{
LiveRangeMapType::iterator HMI = LiveRangeMap.begin(); // hash map iterator
- cout << endl << "Printing Live Ranges from Hash Map:" << endl;
- for( ; HMI != LiveRangeMap.end() ; HMI ++ ) {
- if( (*HMI).first && (*HMI).second ) {
- cout <<" "; printValue((*HMI).first); cout << "\t: ";
- ((*HMI).second)->printSet(); cout << endl;
+ cerr << "\nPrinting Live Ranges from Hash Map:\n";
+ for( ; HMI != LiveRangeMap.end() ; ++HMI) {
+ if( HMI->first && HMI->second ) {
+ cerr <<" "; printValue((*HMI).first); cerr << "\t: ";
+ HMI->second->printSet(); cerr << "\n";
}
}
}