mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-19 19:29:31 +00:00
1164632c7e
* Convert over to valueset interface that uses insert & erase insead of add and remove * the -> operator really isn't that hard to use! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@1687 91177308-0d34-0410-b5e6-96231b3b80d8
291 lines
8.7 KiB
C++
291 lines
8.7 KiB
C++
/* Title: MethodLiveVarInfo.cpp
|
|
Author: Ruchira Sasanka
|
|
Date: Jun 30, 01
|
|
Purpose:
|
|
|
|
This is the interface for live variable info of a method that is required
|
|
by any other part of the compiler.
|
|
|
|
*/
|
|
|
|
|
|
#include "llvm/Analysis/LiveVar/MethodLiveVarInfo.h"
|
|
#include "llvm/CodeGen/MachineInstr.h"
|
|
#include "llvm/BasicBlock.h"
|
|
#include "Support/PostOrderIterator.h"
|
|
#include <iostream>
|
|
using std::cout;
|
|
using std::endl;
|
|
|
|
//************************** Constructor/Destructor ***************************
|
|
|
|
|
|
MethodLiveVarInfo::MethodLiveVarInfo(const Method *const M) : Meth(M) {
|
|
assert(!M->isExternal() && "Cannot be a prototype declaration");
|
|
HasAnalyzed = false; // still we haven't called analyze()
|
|
}
|
|
|
|
|
|
|
|
MethodLiveVarInfo:: ~MethodLiveVarInfo()
|
|
{
|
|
// First delete all BBLiveVar objects created in constructBBs(). A new object
|
|
// of type BBLiveVa is created for every BasicBlock in the method
|
|
|
|
// hash map iterator for BB2BBLVMap
|
|
//
|
|
BBToBBLiveVarMapType::iterator HMI = BB2BBLVMap.begin();
|
|
|
|
for( ; HMI != BB2BBLVMap.end() ; HMI ++ ) {
|
|
if( (*HMI).first ) // delete all BBLiveVar in BB2BBLVMap
|
|
delete (*HMI).second;
|
|
}
|
|
|
|
|
|
// Then delete all objects of type LiveVarSet created in calcLiveVarSetsForBB
|
|
// and entered into MInst2LVSetBI and MInst2LVSetAI (these are caches
|
|
// to return LiveVarSet's before/after a machine instruction quickly). It
|
|
// is sufficient to free up all LiveVarSet using only one cache since
|
|
// both caches refer to the same sets
|
|
|
|
// hash map iterator for MInst2LVSetBI
|
|
//
|
|
MInstToLiveVarSetMapType::iterator MI = MInst2LVSetBI.begin();
|
|
|
|
for( ; MI != MInst2LVSetBI.end() ; MI ++ ) {
|
|
if( (*MI).first ) // delete all LiveVarSets in MInst2LVSetBI
|
|
delete (*MI).second;
|
|
}
|
|
}
|
|
|
|
|
|
// ************************* support functions ********************************
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// constructs BBLiveVars and init Def and In sets
|
|
//-----------------------------------------------------------------------------
|
|
|
|
void MethodLiveVarInfo::constructBBs()
|
|
{
|
|
unsigned int POId = 0; // Reverse Depth-first Order ID
|
|
|
|
po_iterator<const Method*> BBI = po_begin(Meth);
|
|
|
|
for( ; BBI != po_end(Meth) ; ++BBI, ++POId)
|
|
{
|
|
|
|
const BasicBlock *BB = *BBI; // get the current BB
|
|
|
|
if(DEBUG_LV) { cout << " For BB "; printValue(BB); cout << ":" << endl; }
|
|
|
|
// create a new BBLiveVar
|
|
BBLiveVar * LVBB = new BBLiveVar( BB, POId );
|
|
|
|
BB2BBLVMap[ BB ] = LVBB; // insert the pair to Map
|
|
|
|
LVBB->calcDefUseSets(); // calculates the def and in set
|
|
|
|
if(DEBUG_LV)
|
|
LVBB->printAllSets();
|
|
}
|
|
|
|
// Since the PO iterator does not discover unreachable blocks,
|
|
// go over the random iterator and init those blocks as well.
|
|
// However, LV info is not correct for those blocks (they are not
|
|
// analyzed)
|
|
|
|
Method::const_iterator BBRI = Meth->begin(); // random iterator for BBs
|
|
|
|
for( ; BBRI != Meth->end(); ++BBRI, ++POId) {
|
|
|
|
if( ! BB2BBLVMap[ *BBRI ] )
|
|
BB2BBLVMap[ *BBRI ] = new BBLiveVar( *BBRI, POId );
|
|
|
|
}
|
|
|
|
|
|
}
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// do one backward pass over the CFG (for iterative analysis)
|
|
//-----------------------------------------------------------------------------
|
|
bool MethodLiveVarInfo::doSingleBackwardPass()
|
|
{
|
|
bool ResultFlow, NeedAnotherIteration = false;
|
|
|
|
if(DEBUG_LV)
|
|
cout << endl << " After Backward Pass ..." << endl;
|
|
|
|
po_iterator<const Method*> BBI = po_begin(Meth);
|
|
|
|
for( ; BBI != po_end(Meth) ; ++BBI)
|
|
{
|
|
|
|
BBLiveVar* LVBB = BB2BBLVMap[*BBI];
|
|
assert( LVBB );
|
|
|
|
if(DEBUG_LV) cout << " For BB " << (*BBI)->getName() << ":" << endl;
|
|
// cout << " (POId=" << LVBB->getPOId() << ")" << endl ;
|
|
|
|
ResultFlow = false;
|
|
|
|
if( LVBB->isOutSetChanged() )
|
|
LVBB->applyTransferFunc(); // apply the Tran Func to calc InSet
|
|
|
|
if( LVBB->isInSetChanged() ) // to calc Outsets of preds
|
|
ResultFlow = LVBB->applyFlowFunc(BB2BBLVMap);
|
|
|
|
if(DEBUG_LV) LVBB->printInOutSets();
|
|
|
|
|
|
if( ResultFlow ) NeedAnotherIteration = true;
|
|
|
|
}
|
|
|
|
// true if we need to reiterate over the CFG
|
|
return NeedAnotherIteration;
|
|
}
|
|
|
|
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// performs live var anal for a method
|
|
//-----------------------------------------------------------------------------
|
|
void MethodLiveVarInfo::analyze()
|
|
{
|
|
// Don't analyze the same method twice!
|
|
// Later, we need to add change notification here.
|
|
|
|
|
|
if (HasAnalyzed)
|
|
return;
|
|
|
|
|
|
if( DEBUG_LV) cout << "Analysing live variables ..." << endl;
|
|
|
|
// create and initialize all the BBLiveVars of the CFG
|
|
constructBBs();
|
|
|
|
bool NeedAnotherIteration = false;
|
|
do { // do one pass over CFG
|
|
NeedAnotherIteration = doSingleBackwardPass( );
|
|
} while (NeedAnotherIteration ); // repeat until we need more iterations
|
|
|
|
|
|
HasAnalyzed = true; // finished analysing
|
|
|
|
if( DEBUG_LV) cout << "Live Variable Analysis complete!" << endl;
|
|
}
|
|
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
/* Following functions will give the LiveVar info for any machine instr in
|
|
a method. It should be called after a call to analyze().
|
|
|
|
Thsese functions calucluates live var info for all the machine instrs in a
|
|
BB when LVInfo for one inst is requested. Hence, this function is useful
|
|
when live var info is required for many (or all) instructions in a basic
|
|
block. Also, the arguments to this method does not require specific
|
|
iterators.
|
|
*/
|
|
//-----------------------------------------------------------------------------
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// Gives live variable information before a machine instruction
|
|
//-----------------------------------------------------------------------------
|
|
const LiveVarSet *
|
|
MethodLiveVarInfo::getLiveVarSetBeforeMInst(const MachineInstr *const MInst,
|
|
const BasicBlock *const CurBB)
|
|
{
|
|
const LiveVarSet *LVSet = MInst2LVSetBI[MInst];
|
|
|
|
if( LVSet ) return LVSet; // if found, just return the set
|
|
else {
|
|
calcLiveVarSetsForBB( CurBB ); // else, calc for all instrs in BB
|
|
|
|
/*if( ! MInst2LVSetBI[ MInst ] ) {
|
|
cerr << "\nFor BB "; printValue( CurBB);
|
|
cerr << "\nRequested LVSet for inst: " << *MInst;
|
|
}*/
|
|
|
|
assert( MInst2LVSetBI[ MInst ] );
|
|
return MInst2LVSetBI[ MInst ];
|
|
}
|
|
}
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// Gives live variable information after a machine instruction
|
|
//-----------------------------------------------------------------------------
|
|
const LiveVarSet *
|
|
MethodLiveVarInfo::getLiveVarSetAfterMInst(const MachineInstr *const MInst,
|
|
const BasicBlock *const CurBB)
|
|
{
|
|
const LiveVarSet *LVSet = MInst2LVSetAI[MInst];
|
|
|
|
if( LVSet ) return LVSet; // if found, just return the set
|
|
else {
|
|
calcLiveVarSetsForBB( CurBB ); // else, calc for all instrs in BB
|
|
assert( MInst2LVSetAI[ MInst ] );
|
|
return MInst2LVSetAI[ MInst ];
|
|
}
|
|
}
|
|
|
|
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// This method calculates the live variable information for all the
|
|
// instructions in a basic block and enter the newly constructed live
|
|
// variable sets into a the caches ( MInst2LVSetAI, MInst2LVSetBI)
|
|
//-----------------------------------------------------------------------------
|
|
void MethodLiveVarInfo::calcLiveVarSetsForBB(const BasicBlock *const BB)
|
|
{
|
|
const MachineCodeForBasicBlock& MIVec = BB->getMachineInstrVec();
|
|
MachineCodeForBasicBlock::const_reverse_iterator
|
|
MInstIterator = MIVec.rbegin();
|
|
|
|
LiveVarSet *CurSet = new LiveVarSet();
|
|
const LiveVarSet *SetAI = getOutSetOfBB(BB); // init SetAI with OutSet
|
|
CurSet->setUnion(SetAI); // CurSet now contains OutSet
|
|
|
|
// iterate over all the machine instructions in BB
|
|
for( ; MInstIterator != MIVec.rend(); MInstIterator++) {
|
|
|
|
// MInst is cur machine inst
|
|
const MachineInstr * MInst = *MInstIterator;
|
|
|
|
MInst2LVSetAI[MInst] = SetAI; // record in After Inst map
|
|
|
|
CurSet->applyTranferFuncForMInst( MInst ); // apply the transfer Func
|
|
LiveVarSet *NewSet = new LiveVarSet(); // create a new set and
|
|
NewSet->setUnion( CurSet ); // copy the set after T/F to it
|
|
|
|
MInst2LVSetBI[MInst] = NewSet; // record in Before Inst map
|
|
|
|
// SetAI will be used in the next iteration
|
|
SetAI = NewSet;
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|