LV code on machine instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/LiveVar/FunctionLiveVarInfo.cpp b/lib/Analysis/LiveVar/FunctionLiveVarInfo.cpp
index b4126b0..91c2498 100644
--- a/lib/Analysis/LiveVar/FunctionLiveVarInfo.cpp
+++ b/lib/Analysis/LiveVar/FunctionLiveVarInfo.cpp
@@ -1,35 +1,38 @@
-/* Title: ValueSet.h
+/* 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.
+ 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"
/************************** Constructor/Destructor ***************************/
-MethodLiveVarInfo::MethodLiveVarInfo(Method *const MethPtr) : BB2BBLVMap()
-{
- Meth = MethPtr; // init BB2BBLVMap and records Method for future use
+MethodLiveVarInfo::MethodLiveVarInfo(const Method *const M) : Meth(M),
+ BB2BBLVMap()
+{
+ assert(! M->isExternal() ); // cannot be a prototype decleration
+ HasAnalyzed = false; // still we haven't called analyze()
}
MethodLiveVarInfo:: ~MethodLiveVarInfo()
{
- BBToBBLiveVarMapType::iterator HMI = BB2BBLVMap.begin(); // hash map iterator
+ // hash map iterator
+ BBToBBLiveVarMapType::iterator HMI = BB2BBLVMap.begin();
for( ; HMI != BB2BBLVMap.end() ; HMI ++ ) {
- if( (*HMI).first ) // delete all LiveVarSets in BB2BBLVMap
+ if( (*HMI).first ) // delete all LiveVarSets in BB2BBLVMap
delete (*HMI).second;
}
}
@@ -39,38 +42,40 @@
- // constructs BBLiveVars and init Def and In sets
+// constructs BBLiveVars and init Def and In sets
void MethodLiveVarInfo::constructBBs()
{
- unsigned int POId = 0; // Reverse Depth-first Order ID
+ unsigned int POId = 0; // Reverse Depth-first Order ID
cfg::po_const_iterator BBI = cfg::po_begin(Meth);
for( ; BBI != cfg::po_end(Meth) ; ++BBI, ++POId)
{
- if(DEBUG_LV) cout << "-- For BB " << (*BBI)->getName() << ":" << endl ;
+ if(DEBUG_LV) cout << " For BB " << (*BBI)->getName() << ":" << endl ;
- const BasicBlock *BB = *BBI; // get the current BB
- BBLiveVar * LVBB = new BBLiveVar( BB, POId ); // create a new BBLiveVar
+ const BasicBlock *BB = *BBI; // get the current BB
+ // create a new BBLiveVar
+ BBLiveVar * LVBB = new BBLiveVar( BB, POId );
- BB2BBLVMap[ BB ] = LVBB; // insert the pair to Map
+ BB2BBLVMap[ BB ] = LVBB; // insert the pair to Map
- LVBB->calcDefUseSets(); // calculates the def and in set
+ LVBB->calcDefUseSets(); // calculates the def and in set
- if(DEBUG_LV) LVBB->printAllSets();
- //cout << "InSetChanged: " << LVBB->isInSetChanged() << endl;
+ if(DEBUG_LV)
+ LVBB->printAllSets();
}
-
-
}
- // do one backward pass over the CFG
+
+
+// do one backward pass over the CFG
bool MethodLiveVarInfo::doSingleBackwardPass()
{
bool ResultFlow, NeedAnotherIteration = false;
- if(DEBUG_LV) cout << endl << "------- After Backward Pass --------" << endl;
+ if(DEBUG_LV)
+ cout << endl << " After Backward Pass ..." << endl;
cfg::po_const_iterator BBI = cfg::po_begin(Meth);
@@ -80,102 +85,131 @@
BBLiveVar* LVBB = BB2BBLVMap[*BBI];
assert( LVBB );
- if(DEBUG_LV) cout << "-- For BB " << (*BBI)->getName() << ":" << endl;
+ if(DEBUG_LV) cout << " For BB " << (*BBI)->getName() << ":" << endl;
// cout << " (POId=" << LVBB->getPOId() << ")" << endl ;
ResultFlow = false;
if( LVBB->isOutSetChanged() )
- LVBB->applyTransferFunc(); // apply the Transfer Func to calc the InSet
- if( LVBB->isInSetChanged() )
- ResultFlow = LVBB->applyFlowFunc( BB2BBLVMap ); // to calc Outsets of preds
+ 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();
- //cout << "InChanged = " << LVBB->isInSetChanged()
- //cout << " UpdatedBBwithLowerPOId = " << ResultFlow << endl;
+
if( ResultFlow ) NeedAnotherIteration = true;
}
- return NeedAnotherIteration; // true if we need to reiterate over the CFG
+ // true if we need to reiterate over the CFG
+ return NeedAnotherIteration;
}
-void MethodLiveVarInfo::analyze() // performs live var anal for a method
+// performs live var anal for a method
+void MethodLiveVarInfo::analyze()
{
- //cout << "In analyze . . ." << cout;
- constructBBs(); // create and initialize all the BBLiveVars of the CFG
+ if( DEBUG_LV) cout << "Analysing live variables ..." << endl;
+
+ // create and initialize all the BBLiveVars of the CFG
+ constructBBs();
bool NeedAnotherIteration = false;
- do {
- NeedAnotherIteration = doSingleBackwardPass( ); // do one pass over CFG
- } while (NeedAnotherIteration ); // repeat until we need more iterations
+ 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;
}
-/* This function will give the LiveVar info for any instruction in a method. It
- should be called after a call to analyze().
+/* Thsese functions will give the LiveVar info for any machine instruction in
+ a method. It should be called after a call to analyze().
- This function calucluates live var info for all the instructions 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
+ 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.
*/
const LiveVarSet *
-MethodLiveVarInfo::getLiveVarSetBeforeInst(const Instruction *const Inst)
+MethodLiveVarInfo::getLiveVarSetBeforeMInst(const MachineInstr *const MInst,
+ const BasicBlock *const CurBB)
{
- // get the BB corresponding to the instruction
- const BasicBlock *const CurBB = Inst->getParent();
+ const LiveVarSet *LVSet = MInst2LVSetBI[MInst];
- const LiveVarSet *LVSet = Inst2LVSetMap[Inst];
+ if( LVSet ) return LVSet; // if found, just return the set
+ else {
+ calcLiveVarSetsForBB( CurBB ); // else, calc for all instrs in BB
+ assert( MInst2LVSetBI[ MInst ] );
+ return MInst2LVSetBI[ MInst ];
+ }
+}
- if( LVSet ) return LVSet; // if found, just return the set
- const BasicBlock::InstListType& InstListInBB = CurBB->getInstList();
- BasicBlock::InstListType::const_reverse_iterator
- InstItEnd= InstListInBB.rend() - 1; // InstItEnd is set to the first instr
+const LiveVarSet *
+MethodLiveVarInfo::getLiveVarSetAfterMInst(const MachineInstr *const MInst,
+ const BasicBlock *const CurBB)
+{
+ const LiveVarSet *LVSet = MInst2LVSetAI[MInst];
- // LVSet of first instr = InSet
- Inst2LVSetMap[*InstItEnd] = getInSetOfBB( CurBB );
+ 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 ];
+ }
+}
- // if the first instruction is requested, just return the InSet
- if( Inst == *InstItEnd) return Inst2LVSetMap[Inst];
- // else calculate for all other instruction in the BB
-
- BasicBlock::InstListType::const_reverse_iterator
- InstIt= InstListInBB.rbegin(); // get the iterator for instructions in BB
+void MethodLiveVarInfo::calcLiveVarSetsForBB(const BasicBlock *const BB)
+{
+ const MachineCodeForBasicBlock& MIVec = BB->getMachineInstrVec();
+ MachineCodeForBasicBlock::const_reverse_iterator
+ MInstIterator = MIVec.rbegin();
LiveVarSet *CurSet = new LiveVarSet();
- CurSet->setUnion( getOutSetOfBB( CurBB )); // LVSet now contains the OutSet
+ const LiveVarSet *SetAI = getOutSetOfBB(BB); // init SetAI with OutSet
+ CurSet->setUnion(SetAI); // CurSet now contains OutSet
- // calculate LVSet for all instructions in the basic block (except the first)
- for( ; InstIt != InstItEnd ; InstIt++) {
+ // iterate over all the machine instructions in BB
+ for( ; MInstIterator != MIVec.rend(); MInstIterator++) {
- CurSet->applyTranferFuncForInst( *InstIt ); // apply the transfer Func
- LiveVarSet *NewSet = new LiveVarSet(); // create a new set and
- NewSet->setUnion( CurSet ); // copy the set after T/F to it
- Inst2LVSetMap[*InstIt] = NewSet; // record that in the map
+ // 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;
}
-
- return Inst2LVSetMap[Inst];
+
}
-/*
-NOTES: delete all the LVBBs allocated by adding a destructor to the BB2BBLVMap???
- use the dfo_iterator in the doSingleBackwardPass
-*/
+
+
+