* Give BBLiveVar.cpp a proper file header

* applyFlowFunc DOES NOT NEED TO COPY the huge BB->BBLiveVar Map every time it is invoked!
* Big cleanups.
* Make BBLiveVar.h effectively an internal header file
* Prepare LiveVarMap.h for deletion

llvm-svn: 1706
This commit is contained in:
Chris Lattner 2002-02-05 00:34:50 +00:00
parent 94b8baf089
commit 7c70802193
2 changed files with 102 additions and 123 deletions

View File

@ -1,3 +1,9 @@
//===-- BBLiveVar.cpp - Live Variable Analysis for a BasicBlock -----------===//
//
// This is a wrapper class for BasicBlock which is used by live var analysis.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/LiveVar/BBLiveVar.h"
#include "llvm/Analysis/LiveVar/MethodLiveVarInfo.h"
#include "llvm/CodeGen/MachineInstr.h"
@ -7,113 +13,85 @@
#include "../../Target/Sparc/SparcInternals.h" // Only for PHI defn
using std::cerr;
using std::endl;
using std::pair;
//-----------------------------------------------------------------------------
// Constructor
//-----------------------------------------------------------------------------
BBLiveVar::BBLiveVar( const BasicBlock *const baseBB, unsigned int RdfoId)
: BaseBB(baseBB), DefSet(), InSet(),
OutSet(), PhiArgMap() {
BaseBB = baseBB;
InSetChanged = OutSetChanged = false;
POId = RdfoId;
BBLiveVar::BBLiveVar(const BasicBlock *bb, unsigned id)
: BB(bb), POID(id) {
InSetChanged = OutSetChanged = false;
}
//-----------------------------------------------------------------------------
// caluculates def and use sets for each BB
// calculates def and use sets for each BB
// There are two passes over operands of a machine instruction. This is
// because, we can have instructions like V = V + 1, since we no longer
// assume single definition.
//-----------------------------------------------------------------------------
void BBLiveVar::calcDefUseSets()
{
void BBLiveVar::calcDefUseSets() {
// get the iterator for machine instructions
const MachineCodeForBasicBlock& MIVec = BaseBB->getMachineInstrVec();
MachineCodeForBasicBlock::const_reverse_iterator
MInstIterator = MIVec.rbegin();
const MachineCodeForBasicBlock &MIVec = BB->getMachineInstrVec();
// iterate over all the machine instructions in BB
for( ; MInstIterator != MIVec.rend(); ++MInstIterator) {
const MachineInstr * MInst = *MInstIterator; // MInst is the machine inst
assert(MInst);
for (MachineCodeForBasicBlock::const_reverse_iterator MII = MIVec.rbegin(),
MIE = MIVec.rend(); MII != MIE; ++MII) {
const MachineInstr *MI = *MII;
if( DEBUG_LV > 1) { // debug msg
if (DEBUG_LV > 1) { // debug msg
cerr << " *Iterating over machine instr ";
MInst->dump();
MI->dump();
cerr << "\n";
}
// iterate over MI operands to find defs
for( MachineInstr::val_const_op_iterator OpI(MInst); !OpI.done() ; ++OpI) {
if( OpI.isDef() ) // add to Defs only if this operand is a def
addDef( *OpI );
}
for (MachineInstr::val_const_op_iterator OpI(MI); !OpI.done(); ++OpI)
if (OpI.isDef()) // add to Defs only if this operand is a def
addDef(*OpI);
// do for implicit operands as well
for( unsigned i=0; i < MInst->getNumImplicitRefs(); ++i) {
if( MInst->implicitRefIsDefined(i) )
addDef( MInst->getImplicitRef(i) );
}
for (unsigned i = 0; i < MI->getNumImplicitRefs(); ++i)
if (MI->implicitRefIsDefined(i))
addDef(MI->getImplicitRef(i));
bool IsPhi = ( MInst->getOpCode() == PHI );
bool IsPhi = MI->getOpCode() == PHI;
// iterate over MI operands to find uses
for (MachineInstr::val_const_op_iterator OpI(MInst); !OpI.done() ; ++OpI) {
// iterate over MI operands to find uses
for (MachineInstr::val_const_op_iterator OpI(MI); !OpI.done(); ++OpI) {
const Value *Op = *OpI;
if ( ((Op)->getType())->isLabelType() )
if (Op->getType()->isLabelType())
continue; // don't process labels
if(! OpI.isDef() ) { // add to Defs only if this operand is a use
addUse( Op );
if (!OpI.isDef()) { // add to Defs only if this operand is a use
addUse(Op);
if( IsPhi ) { // for a phi node
if (IsPhi) { // for a phi node
// put args into the PhiArgMap (Val -> BB)
const Value * ArgVal = Op;
++OpI; // increment to point to BB of value
const Value * BBVal = *OpI;
const Value *ArgVal = Op;
const Value *BBVal = *++OpI; // increment to point to BB of value
PhiArgMap[ArgVal] = cast<BasicBlock>(BBVal);
assert( (BBVal)->getValueType() == Value::BasicBlockVal );
PhiArgMap[ ArgVal ] = (const BasicBlock *) (BBVal);
assert( PhiArgMap[ ArgVal ] );
if( DEBUG_LV > 1) { // debug msg of level 2
if (DEBUG_LV > 1) {
cerr << " - phi operand ";
printValue( ArgVal );
printValue(ArgVal);
cerr << " came from BB ";
printValue( PhiArgMap[ ArgVal ]);
printValue(PhiArgMap[ArgVal]);
cerr << "\n";
}
} // if( IsPhi )
} // if a use
} // for all operands
// do for implicit operands as well
for( unsigned i=0; i < MInst->getNumImplicitRefs(); ++i) {
for (unsigned i = 0; i < MI->getNumImplicitRefs(); ++i) {
assert(!IsPhi && "Phi cannot have implicit opeands");
const Value *Op = MI->getImplicitRef(i);
assert( !IsPhi && "Phi cannot have implicit opeands");
const Value *Op = MInst->getImplicitRef(i);
if ( ((Op)->getType())->isLabelType() )
continue; // don't process labels
if( ! MInst->implicitRefIsDefined(i) )
addUse( Op );
}
if (Op->getType()->isLabelType()) // don't process labels
continue;
if (!MI->implicitRefIsDefined(i))
addUse(Op);
}
} // for all machine instructions
}
@ -122,13 +100,12 @@ void BBLiveVar::calcDefUseSets()
//-----------------------------------------------------------------------------
// To add an operand which is a def
//-----------------------------------------------------------------------------
void BBLiveVar::addDef(const Value *Op)
{
void BBLiveVar::addDef(const Value *Op) {
DefSet.insert(Op); // operand is a def - so add to def set
InSet.erase(Op); // this definition kills any uses
InSet.erase(Op); // this definition kills any uses
InSetChanged = true;
if( DEBUG_LV > 1) {
if (DEBUG_LV > 1) {
cerr << " +Def: "; printValue( Op ); cerr << "\n";
}
}
@ -137,16 +114,14 @@ void BBLiveVar::addDef(const Value *Op)
//-----------------------------------------------------------------------------
// To add an operand which is a use
//-----------------------------------------------------------------------------
void BBLiveVar::addUse(const Value *Op)
{
void BBLiveVar::addUse(const Value *Op) {
InSet.insert(Op); // An operand is a use - so add to use set
OutSet.erase(Op); // remove if there is a def below this use
InSetChanged = true;
if( DEBUG_LV > 1) { // debug msg of level 2
cerr << " Use: "; printValue( Op ); cerr << endl;
if (DEBUG_LV > 1) {
cerr << " Use: "; printValue( Op ); cerr << "\n";
}
}
@ -155,18 +130,15 @@ void BBLiveVar::addUse(const Value *Op)
// the outset.
//-----------------------------------------------------------------------------
bool BBLiveVar::applyTransferFunc() // calculates the InSet in terms of OutSet
{
bool BBLiveVar::applyTransferFunc() {
// IMPORTANT: caller should check whether the OutSet changed
// (else no point in calling)
LiveVarSet OutMinusDef; // set to hold (Out[B] - Def[B])
OutMinusDef.setDifference( &OutSet, &DefSet);
InSetChanged = InSet.setUnion( &OutMinusDef );
OutMinusDef.setDifference(&OutSet, &DefSet);
InSetChanged = InSet.setUnion(&OutMinusDef);
OutSetChanged = false; // no change to OutSet since transf func applied
return InSetChanged;
}
@ -174,80 +146,70 @@ bool BBLiveVar::applyTransferFunc() // calculates the InSet in terms of OutSet
//-----------------------------------------------------------------------------
// calculates Out set using In sets of the predecessors
//-----------------------------------------------------------------------------
bool BBLiveVar::setPropagate( LiveVarSet *const OutSet,
const LiveVarSet *const InSet,
const BasicBlock *const PredBB) {
LiveVarSet::const_iterator InIt;
pair<LiveVarSet::iterator, bool> result;
bool changed = false;
const BasicBlock *PredBBOfPhiArg;
bool BBLiveVar::setPropagate(LiveVarSet *OutSet, const LiveVarSet *InSet,
const BasicBlock *PredBB) {
bool Changed = false;
// for all all elements in InSet
for( InIt = InSet->begin() ; InIt != InSet->end(); InIt++) {
PredBBOfPhiArg = PhiArgMap[ *InIt ];
for (LiveVarSet::const_iterator InIt = InSet->begin(), InE = InSet->end();
InIt != InE; ++InIt) {
const BasicBlock *PredBBOfPhiArg = PhiArgMap[*InIt];
// if this var is not a phi arg OR
// it's a phi arg and the var went down from this BB
if( !PredBBOfPhiArg || PredBBOfPhiArg == PredBB) {
result = OutSet->insert( *InIt ); // insert to this set
if( result.second == true) changed = true;
}
if (!PredBBOfPhiArg || PredBBOfPhiArg == PredBB)
if (OutSet->insert(*InIt).second)
Changed = true;
}
return changed;
return Changed;
}
//-----------------------------------------------------------------------------
// propogates in set to OutSets of PREDECESSORs
//-----------------------------------------------------------------------------
bool BBLiveVar::applyFlowFunc(BBToBBLiveVarMapType LVMap)
{
bool BBLiveVar::applyFlowFunc(std::map<const BasicBlock *, BBLiveVar *> &LVMap){
// IMPORTANT: caller should check whether inset changed
// (else no point in calling)
bool needAnotherIt= false; // did this BB change any OutSets of pred.s
// whose POId is lower
// If this BB changed any OutSets of preds whose POID is lower, than we need
// another iteration...
//
bool needAnotherIt = false;
for (BasicBlock::pred_const_iterator PI = BB->pred_begin(),
PE = BB->pred_begin(); PI != PE ; ++PI) {
BBLiveVar *PredLVBB = LVMap[*PI];
BasicBlock::pred_const_iterator PredBBI = BaseBB->pred_begin();
for( ; PredBBI != BaseBB->pred_end() ; PredBBI++) {
assert( *PredBBI ); // assert that the predecessor is valid
BBLiveVar *PredLVBB = LVMap[*PredBBI];
// do set union
if( setPropagate( &(PredLVBB->OutSet), &InSet, *PredBBI ) == true) {
// do set union
if (setPropagate(&PredLVBB->OutSet, &InSet, *PI)) {
PredLVBB->OutSetChanged = true;
// if the predec POId is lower than mine
if( PredLVBB->getPOId() <= POId)
// if the predec POID is lower than mine
if (PredLVBB->getPOId() <= POID)
needAnotherIt = true;
}
} // for
return needAnotherIt;
}
/* ----------------- Methods For Debugging (Printing) ----------------- */
// ----------------- Methods For Debugging (Printing) -----------------
void BBLiveVar::printAllSets() const
{
cerr << " Defs: "; DefSet.printSet(); cerr << endl;
cerr << " In: "; InSet.printSet(); cerr << endl;
cerr << " Out: "; OutSet.printSet(); cerr << endl;
void BBLiveVar::printAllSets() const {
cerr << " Defs: "; DefSet.printSet(); cerr << "\n";
cerr << " In: "; InSet.printSet(); cerr << "\n";
cerr << " Out: "; OutSet.printSet(); cerr << "\n";
}
void BBLiveVar::printInOutSets() const
{
cerr << " In: "; InSet.printSet(); cerr << endl;
cerr << " Out: "; OutSet.printSet(); cerr << endl;
void BBLiveVar::printInOutSets() const {
cerr << " In: "; InSet.printSet(); cerr << "\n";
cerr << " Out: "; OutSet.printSet(); cerr << "\n";
}

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@ -10,6 +10,7 @@
#include "llvm/Analysis/LiveVar/MethodLiveVarInfo.h"
#include "llvm/Analysis/LiveVar/BBLiveVar.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/BasicBlock.h"
#include "Support/PostOrderIterator.h"
@ -17,6 +18,20 @@
AnalysisID MethodLiveVarInfo::ID(AnalysisID::create<MethodLiveVarInfo>());
//-----------------------------------------------------------------------------
// Accessor Functions
//-----------------------------------------------------------------------------
// gets OutSet of a BB
const LiveVarSet *MethodLiveVarInfo::getOutSetOfBB(const BasicBlock *BB) const {
return BB2BBLVMap.find(BB)->second->getOutSet();
}
// gets InSet of a BB
const LiveVarSet *MethodLiveVarInfo::getInSetOfBB(const BasicBlock *BB) const {
return BB2BBLVMap.find(BB)->second->getInSet();
}
//-----------------------------------------------------------------------------
// Performs live var analysis for a method
@ -103,7 +118,8 @@ void MethodLiveVarInfo::releaseMemory() {
// First delete all BBLiveVar objects created in constructBBs(). A new object
// of type BBLiveVar is created for every BasicBlock in the method
//
for (BBToBBLiveVarMapType::iterator HMI = BB2BBLVMap.begin(),
for (std::map<const BasicBlock *, BBLiveVar *>::iterator
HMI = BB2BBLVMap.begin(),
HME = BB2BBLVMap.end(); HMI != HME; ++HMI)
delete HMI->second; // delete all BBLiveVar in BB2BBLVMap
@ -115,7 +131,8 @@ void MethodLiveVarInfo::releaseMemory() {
// is sufficient to free up all LiveVarSet using only one cache since
// both caches refer to the same sets
//
for (MInstToLiveVarSetMapType::iterator MI = MInst2LVSetBI.begin(),
for (std::map<const MachineInstr*, const LiveVarSet*>::iterator
MI = MInst2LVSetBI.begin(),
ME = MInst2LVSetBI.end(); MI != ME; ++MI)
delete MI->second; // delete all LiveVarSets in MInst2LVSetBI