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			assert(NewIdom != SMP_BLOCKNUM_UNINIT);
			// Loop through all predecessors of block RPONum except block NewIdom.
			//  Set NewIdom to the intersection of its Dom set and the Doms set of
			//  each predecessor that has had its Doms set computed.
			for (CurrPred = CurrBlock->GetFirstPred(); CurrPred != CurrBlock->GetLastPred(); ++CurrPred) {
				int PredNum = (*CurrPred)->GetNumber();
				if (DebugFlag) SMP_msg("PredNum: %d\n", PredNum);
				// **!!** We can avoid failure on unreachable basic blocks
				//  by executing a continue statement if PredNum is -1. Long term solution
				//  is to prune out unreachable basic blocks, or better yet, create hell nodes
				//  if the function has indirect jumps.
				if (PredNum == SMP_BLOCKNUM_UNINIT)
					continue;
				int PredIDOM = this->IDom.at(PredNum);
				if (DebugFlag) SMP_msg("PredIDOM: %d\n", PredIDOM);
				if ((SMP_BLOCKNUM_UNINIT == PredIDOM) || (NewIdom == PredIDOM)) {
					// Skip predecessors that have uncomputed Dom sets, or are the
					//  current NewIdom.
					continue;
				}
				if (DebugFlag) SMP_msg("Old NewIdom value: %d\n", NewIdom);
				NewIdom = this->IntersectDoms(PredNum, NewIdom);
				if (DebugFlag) SMP_msg("New NewIdom value: %d\n", NewIdom);
			}
			// If NewIdom is not the value currently in vector IDom[], update the
			//  vector entry and set changed to true.
			if (NewIdom != this->IDom.at(RPONum)) {
				if (DebugFlag) SMP_msg("IDOM changed from %d to %d\n", this->IDom.at(RPONum), NewIdom);
				this->IDom[RPONum] = NewIdom;
				changed = true;
			}
		}
	} while (changed);
	return;
} // end of SMPFunction::ComputeIDoms()

// Compute dominance frontier sets for each block.
void SMPFunction::ComputeDomFrontiers(void) {
	list<SMPBasicBlock *>::iterator BlockIter;
	SMPBasicBlock *RunnerBlock;
	SMPBasicBlock *CurrBlock;
	for (BlockIter = this->Blocks.begin(); BlockIter != this->Blocks.end(); ++BlockIter) {
		CurrBlock = (*BlockIter);
		// We look only at join points in the CFG, as per Cooper/Torczon chapter 9.
		if (1 < CurrBlock->GetNumPreds()) { // join point; more than 1 predecessor
			int runner;
			list<SMPBasicBlock *>::iterator PredIter;
			SMPBasicBlock *CurrPred;
			for (PredIter = CurrBlock->GetFirstPred(); PredIter != CurrBlock->GetLastPred(); ++PredIter) {
				CurrPred = (*PredIter);
				// For each predecessor, we run up the IDom[] vector and add CurrBlock to the
				//  DomFrontier for all blocks that are between CurrPred and IDom[CurrBlock],
				//  not including IDom[CurrBlock] itself.
				runner = CurrPred->GetNumber();
				while (runner != this->IDom.at(CurrBlock->GetNumber())) {
					// Cooper/Harvey/Kennedy paper does not quite agree with the later
					//  text by Cooper/Torczon. Text says that the start node has no IDom
					//  in the example on pages 462-463, but it shows an IDOM for the
					//  root node in Figure 9.9 of value == itself. The first edition text
					//  on p.463 seems correct, as the start node dominates every node and
					//  thus should have no dominance frontier.
					if (SMP_TOP_BLOCK == runner)
						break;
					RunnerBlock = this->RPOBlocks.at(runner);
					RunnerBlock->AddToDomFrontier(CurrBlock->GetNumber());
					runner = this->IDom.at(runner);
				}
			} // end for all predecessors
		} // end if join point
	} // end for all blocks
	return;
} // end of SMPFunction::ComputeDomFrontiers()

// Compute the GlobalNames set, which includes all operands that are used in more than
//  one basic block. It is the union of all UpExposedSets of all blocks.
void SMPFunction::ComputeGlobalNames(void) {
	set<op_t, LessOp>::iterator SetIter;
	list<SMPBasicBlock *>::iterator BlockIter;
	SMPBasicBlock *CurrBlock;
	unsigned int index = 0;
	if (this->Blocks.size() < 2)
		return; // cannot have global names if there is only one block

	bool DebugFlag = false;
#if SMP_DEBUG_DATAFLOW
	DebugFlag = (0 == strcmp("uw_frame_state_for", this->GetFuncName()));
	for (BlockIter = this->Blocks.begin(); BlockIter != this->Blocks.end(); ++BlockIter) {
		CurrBlock = (*BlockIter);
		for (SetIter = CurrBlock->GetFirstUpExposed(); SetIter != CurrBlock->GetLastUpExposed(); ++SetIter) {
			op_t TempOp = *SetIter;
			// The GlobalNames set will have the complete collection of operands that we are
			//  going to number in our SSA computations. We now assign an operand number
			//  within the op_t structure for each, so that we can index into the
			//  BlocksUsedIn[] vector, for example. This operand number is not to be
			//  confused with SSA numbers.
			// We use the operand number field op_t.n for the lower 8 bits, and the offset
			//  fields op_t.offb:op_t.offo for the upper 16 bits. We are overwriting IDA
			//  values here, but operands in the data flow analysis sets should never be
			//  inserted back into the program anyway.
#endif
			set<op_t, LessOp>::iterator AlreadyInSet;
			pair<set<op_t, LessOp>::iterator, bool> InsertResult;
			InsertResult = this->GlobalNames.insert(TempOp);
			if (!InsertResult.second) {
				// Already in GlobalNames, so don't assign an index number.
				;
#if SMP_DEBUG_DATAFLOW
#endif
			}
			else {
				++index;
#if SMP_DEBUG_DATAFLOW
					SMP_msg(" inserted as index %d\n", ExtractGlobalIndex(TempOp));
#endif
			}
		} // for each upward exposed item in the current block
	} // for each basic block

	assert(16777215 >= this->GlobalNames.size()); // index fits in 24 bits
	return;
} // end of SMPFunction::ComputeGlobalNames()

// For each item in GlobalNames, record the blocks that DEF the item.
void SMPFunction::ComputeBlocksDefinedIn(void) {
	// Loop through all basic blocks and examine all DEFs. For Global DEFs, record
	//  the block number in BlocksDefinedIn. The VarKillSet records DEFs without
	//  having to examine every instruction.
	list<SMPBasicBlock *>::iterator BlockIter;
	SMPBasicBlock *CurrBlock;

	this->BlocksDefinedIn.clear();
	for (size_t i = 0; i < this->GlobalNames.size(); ++i) {
		list<int> TempList;
		this->BlocksDefinedIn.push_back(TempList);
	}
	SMP_msg("Number of GlobalNames: %d\n", this->GlobalNames.size());
	SMP_msg("Size of BlocksDefinedIn: %d\n", this->BlocksDefinedIn.size());
	for (BlockIter = this->Blocks.begin(); BlockIter != this->Blocks.end(); ++BlockIter) {
		set<op_t, LessOp>::iterator KillIter;
		CurrBlock = (*BlockIter);
		for (KillIter = CurrBlock->GetFirstVarKill(); KillIter != CurrBlock->GetLastVarKill(); ++KillIter) {
			// If killed item is not a block-local item (it is global), record it.
			set<op_t, LessOp>::iterator NameIter = this->GlobalNames.find(*KillIter);
			if (NameIter != this->GlobalNames.end()) { // found in GlobalNames set
				// We have a kill of a global name. Get index from three 8-bit fields.
				unsigned int index = ExtractGlobalIndex(*NameIter);
				if (index >= this->GlobalNames.size()) {
					// We are about to assert false.
					SMP_msg("ComputeBlocksDefinedIn: Bad index: %d limit: %zu\n", index,
						this->GlobalNames.size());
					SMP_msg("Block number %d\n", CurrBlock->GetNumber());
					SMP_msg("Killed item: ");
					PrintListOperand(*KillIter);
					SMP_msg("\n");
					SMP_msg("This is a fatal error.\n");
				assert(index < this->GlobalNames.size());
				// index is a valid subscript for the BlocksDefinedIn vector. Push the
				//  current block number onto the list of blocks that define this global name.
				this->BlocksDefinedIn[index].push_back(CurrBlock->GetNumber());
			}			
		}
	}
	return;
} // end of SMPFunction::ComputeBlocksDefinedIn()

// Compute the phi functions at the entry point of each basic block that is a join point.
void SMPFunction::InsertPhiFunctions(void) {
	set<op_t, LessOp>::iterator NameIter;
	list<int> WorkList;  // list of block numbers
	bool DebugFlag = false;
#if SMP_DEBUG_DATAFLOW
	DebugFlag = (0 == strcmp("uw_frame_state_for", this->GetFuncName()));
	if (DebugFlag) SMP_msg("GlobalNames size: %zu\n", this->GlobalNames.size());
	for (NameIter = this->GlobalNames.begin(); NameIter != this->GlobalNames.end(); ++NameIter) {
		int CurrNameIndex = (int) (ExtractGlobalIndex(*NameIter));
		if (DebugFlag) SMP_msg("CurrNameIndex: %d\n", CurrNameIndex);
#if 0
		DebugFlag = (DebugFlag && (6 == CurrNameIndex));
#endif
		// Initialize the work list to all blocks that define the current name.
		WorkList.clear();
		list<int>::iterator WorkIter;
		for (WorkIter = this->BlocksDefinedIn.at((size_t) CurrNameIndex).begin();
			WorkIter != this->BlocksDefinedIn.at((size_t) CurrNameIndex).end();
			++WorkIter) {
			WorkList.push_back(*WorkIter);
		}

		// Iterate through the work list, inserting phi functions for the current name
		//  into all the blocks in the dominance frontier of each work list block.
		//  Insert into the work list each block that had a phi function added.
		while (!WorkList.empty()) {
			if (DebugFlag) SMP_msg("WorkList size: %d\n", WorkList.size());
			list<int>::iterator WorkIter = WorkList.begin();
			while (WorkIter != WorkList.end()) {
				set<int>::iterator DomFrontIter;
				if (DebugFlag) SMP_msg("WorkIter: %d\n", *WorkIter);
#endif
				if (DebugFlag && (*WorkIter > this->BlockCount)) {
					SMP_msg("ERROR: WorkList block # %d out of range.\n", *WorkIter);
				SMPBasicBlock *WorkBlock = this->RPOBlocks[*WorkIter];
				for (DomFrontIter = WorkBlock->GetFirstDomFrontier();
					DomFrontIter != WorkBlock->GetLastDomFrontier();
					++DomFrontIter) {
					if (DebugFlag) SMP_msg("DomFront: %d\n", *DomFrontIter);
#endif
					if (DebugFlag && (*DomFrontIter > this->BlockCount)) {
						SMP_msg("ERROR: DomFront block # %d out of range.\n", *DomFrontIter);
					SMPBasicBlock *PhiBlock = this->RPOBlocks[*DomFrontIter];
					// Before inserting a phi function for the current name in *PhiBlock,
					//  see if the current name is LiveIn for *PhiBlock. If not, there
					//  is no need for the phi function. This check is what makes the SSA
					//  a fully pruned SSA.
					if (PhiBlock->IsLiveIn(*NameIter)) {
						size_t NumPreds = PhiBlock->GetNumPreds();
						DefOrUse CurrRef(*NameIter);
						SMPPhiFunction CurrPhi(CurrNameIndex, CurrRef);
						for (size_t NumCopies = 0; NumCopies < NumPreds; ++NumCopies) {
							CurrPhi.PushBack(CurrRef); // inputs to phi
						}
						if (PhiBlock->AddPhi(CurrPhi)) {
							// If not already in Phi set, new phi function was inserted.
							WorkList.push_back(PhiBlock->GetNumber());
							if (DebugFlag) SMP_msg("Added phi for name %d at top of block %d\n", CurrNameIndex, PhiBlock->GetNumber());
							SMP_msg("Global %d not LiveIn for block %d\n", CurrNameIndex, PhiBlock->GetNumber());
						}
					}
				} // end for all blocks in the dominance frontier
				// Remove current block number from the work list
					SMP_msg("Removing block %d from work list.\n", *WorkIter);
				WorkIter = WorkList.erase(WorkIter);
			} // end for all block numbers in the work list
		} // end while the work list is not empty
		if (DebugFlag) SMP_msg("WorkList empty.\n");
	} // end for all elements of the GlobalNames set
	return;
} // end of SMPFunction::InsertPhiFunctions()

// Build the dominator tree.
void SMPFunction::BuildDominatorTree(void) {
	size_t index;
	// First, fill the DomTree vector with the parent numbers filled in and the child lists
	//  left empty.
	for (index = 0; index < this->IDom.size(); ++index) {
		pair<int, list<int> > DomTreeEntry;
		DomTreeEntry.first = this->IDom.at(index);
		DomTreeEntry.second.clear();
		this->DomTree.push_back(DomTreeEntry);
	}
	// Now, push the children onto the appropriate lists.
	for (index = 0; index < this->IDom.size(); ++index) {
		// E.g. if block 5 has block 3 as a parent, then we fetch the number 3
		//  using the expression this->DomTree.at(index).first, which was just
		//  initialized in the previous loop. Then we go to DomTree entry 3 and push
		//  the number 5 on its child list.
		int parent = this->DomTree.at(index).first;
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		if (parent != (int) index) // block can dominate itself, but not in DomTree!
			this->DomTree.at(parent).second.push_back((int) index);
	}

	return;
} // end of SMPFunction::BuildDominatorTree()

// Helper for SSA subscript renumbering: return the next SSA number for the global name
//  and increment the SSACounter to prepare the next number. Push the returned number onto
//  the SSAStack for the global name.
int SMPFunction::SSANewNumber(size_t GlobNameIndex) {
	int Subscript = this->SSACounter.at(GlobNameIndex);
	++(this->SSACounter[GlobNameIndex]);
	this->SSAStack[GlobNameIndex].push_back(Subscript);
	return Subscript;
} // end of SMPFunction::SSANewNumber()

// Main helper for SSA subscript renumbering. Renumber within block throughout its phi
//  functions, then its DEFs and USEs, then its phi successors. Recurse then on all
//  successors in the dominator tree.
void SMPFunction::SSARename(int BlockNumber) {
	assert(0 <= BlockNumber);
	assert(BlockNumber < this->BlockCount);
	SMPBasicBlock *CurrBlock = this->RPOBlocks.at((size_t) BlockNumber);
	DumpFlag |=	(0 == strcmp("main", this->GetFuncName()));
	DumpFlag |= (0 == strcmp("dohanoi", this->GetFuncName()));
	DumpFlag |= (0 == strcmp("uw_frame_state_for", this->GetFuncName()));
	DumpFlag |= (0 == strcmp("_IO_sputbackc", this->GetFuncName()));
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#endif
	if (DumpFlag) SMP_msg("Entered SSARename for block number %d\n", BlockNumber);

	// For each phi function at the top of the block, rename the DEF of the phi function
	//  using SSANewNumber() on the global name index.
	set<SMPPhiFunction, LessPhi>::iterator CurrPhi;
	list<SMPPhiFunction> TempPhiList;
	int GlobalNameIndex;
	for (CurrPhi = CurrBlock->GetFirstPhi(); CurrPhi != CurrBlock->GetLastPhi(); ++CurrPhi) {
		op_t PhiDefOp = CurrPhi->GetAnyOp();
		GlobalNameIndex = CurrPhi->GetIndex();
		assert(0 <= GlobalNameIndex);
		int NewSSANum = this->SSANewNumber((size_t) GlobalNameIndex);

		// Cannot change the C++ STL set item directly, as sets might become unordered.
		SMPPhiFunction TempPhi = (*CurrPhi);
		TempPhi.SetSSADef(NewSSANum);
		TempPhiList.push_back(TempPhi);
		if (o_reg == PhiDefOp.type) {
			if (DumpFlag && DefOp.is_reg(R_ax)) {
				SMP_msg("New EAX Phi Def SSANum: %d Block %d\n", NewSSANum, BlockNumber);
			}
			// Map the final SSA number to the block number.
			int DefHashValue = HashGlobalNameAndSSA(PhiDefOp, NewSSANum);
			pair<int, ea_t> DefMapEntry(DefHashValue, CurrBlock->GetNumber());
			pair<map<int, ea_t>::iterator, bool> MapReturnValue;
			MapReturnValue = this->GlobalDefAddrBySSA.insert(DefMapEntry);
			assert(MapReturnValue.second);
		}
	}
	// Go back through the Phi function set and replace the items that need to be updated.
	list<SMPPhiFunction>::iterator TempIter;
	for (TempIter = TempPhiList.begin(); TempIter != TempPhiList.end(); ++TempIter) {
		// Use the op_t from the first phi use, because they are all the same.
		bool Erased = CurrBlock->ErasePhi(TempIter->GetPhiRef(0).GetOp());
		assert(Erased);
		// Now we can add back the phi function that had the DEF SSA number changed.
		bool Added = CurrBlock->AddPhi(*TempIter);
		assert(Added);
	}
	TempPhiList.clear();
	if (DumpFlag) SMP_msg("Processed phi functions at top.\n");

	// For each instruction in the block, rename all global USEs and then all global DEFs.
	list<SMPInstr *>::iterator InstIter;
	SMPInstr *CurrInst;
	for (InstIter = CurrBlock->GetFirstInstr(); InstIter != CurrBlock->GetLastInstr(); ++InstIter) {
		CurrInst = (*InstIter);
		set<DefOrUse, LessDefUse>::iterator CurrUse = CurrInst->GetFirstUse();
		ea_t InstAddr = CurrInst->GetAddr(); // for debugging break points
		while (CurrUse != CurrInst->GetLastUse()) {
			// See if Use is a global name.
			UseOp = CurrUse->GetOp();
			set<op_t, LessOp>::iterator GlobIter = this->GlobalNames.find(UseOp);
			if (GlobIter != this->GlobalNames.end()) { // found it
				unsigned int GlobIndex = ExtractGlobalIndex(*GlobIter);
				if (GlobIndex > this->SSAStack.size()) {
					// Get some debug info out to the log file before we crash.
					SMP_msg("Bad GlobIndex: %d at %x in %s\n", GlobIndex, InstAddr, this->GetFuncName());
					exit(EXIT_FAILURE);
				}
				// Set the SSA number for this use to the top of stack SSA # (back())
				int NewSSANum;
				if (this->SSAStack.at(GlobIndex).empty()) {
					// No top of stack entry to read.
#if SMP_DEBUG_UNINITIALIZED_SSA_NAMES
					if (!CurrInst->MDIsPopInstr() && (o_reg == UseOp.type)) {
						// POP uses the stack offset and generates spurious
						//  uninitialized variable messages for [esp+0].
						SMP_msg("WARNING: function %s : Use of uninitialized variable: ",
						SMP_msg(" Block number: %d Address: %x Instruction: %s\n", BlockNumber,
							CurrInst->GetAddr(), CurrInst->GetDisasm());
#endif
					NewSSANum = SMP_SSA_UNINIT;
				}
				else {
					NewSSANum = this->SSAStack.at(GlobIndex).back();
				}
				CurrUse = CurrInst->SetUseSSA(UseOp, NewSSANum);
				if (DumpFlag && (o_reg == UseOp.type) && UseOp.is_reg(R_ax)) {
					SMP_msg("New EAX Use SSANum: %d at %x\n", NewSSANum, CurrInst->GetAddr());
		set<DefOrUse, LessDefUse>::iterator CurrDef = CurrInst->GetFirstDef();
		while (CurrDef != CurrInst->GetLastDef()) {
			// See if Def is a global name.
			DefOp = CurrDef->GetOp();
			set<op_t, LessOp>::iterator GlobIter = this->GlobalNames.find(DefOp);
			if (GlobIter != this->GlobalNames.end()) { // found it
				unsigned int GlobIndex = ExtractGlobalIndex(*GlobIter);
				// Set the SSA number for this DEF to the SSANewNumber top of stack
				int NewSSANum = this->SSANewNumber(GlobIndex);
				CurrDef = CurrInst->SetDefSSA(DefOp, NewSSANum);
				if (o_reg == DefOp.type) {
					if (DumpFlag && DefOp.is_reg(R_ax)) {
						SMP_msg("New EAX Def SSANum: %d at %x\n", NewSSANum, DefAddr);
					}

					// Map the final SSA number to the DEF address.
					int DefHashValue = HashGlobalNameAndSSA(DefOp, NewSSANum);
					pair<int, ea_t> DefMapEntry(DefHashValue, DefAddr);
					pair<map<int, ea_t>::iterator, bool> MapReturnValue;
					MapReturnValue = this->GlobalDefAddrBySSA.insert(DefMapEntry);
					assert(MapReturnValue.second);
				}
		} //  end for all DEFs
	} // end for all instructions
	if (DumpFlag) SMP_msg("Processed all instructions.\n");

	// For all control flow graph (not dominator tree) successors, fill in the current
	//  (outgoing) SSA number in the corresponding USE slot in the phi function, for all
	//  global names appearing in phi functions.
	list<SMPBasicBlock *>::iterator SuccIter;
	for (SuccIter = CurrBlock->GetFirstSucc(); SuccIter != CurrBlock->GetLastSucc(); ++SuccIter) {
		// What position in the Preds list of this successor is CurrBlock?
		int ListPos = (*SuccIter)->GetPredPosition(BlockNumber);
		assert(0 <= ListPos);

		// Go through all phi functions in this successor. At ListPos position in the
		//  incoming arguments for that phi function, set the SSA number to the SSA number
		//  in the top of stack entry for the global name associated with that phi function.
		set<SMPPhiFunction, LessPhi>::iterator CurrPhi;
		for (CurrPhi = (*SuccIter)->GetFirstPhi(); CurrPhi != (*SuccIter)->GetLastPhi(); ++CurrPhi) {
			int GlobIndex = CurrPhi->GetIndex();
			int CurrSSA;
			if (this->SSAStack.at(GlobIndex).empty()) {
				// No top of stack entry to read.
#if SMP_DEBUG_UNINITIALIZED_SSA_NAMES
				SMP_msg("WARNING: function %s : Path to use of uninitialized variable: ",
				PrintListOperand(CurrPhi->GetAnyOp());
				SMP_msg(" Block number: %d Successor block number: %d\n", BlockNumber,
					(*SuccIter)->GetNumber());
#endif
				CurrSSA = SMP_SSA_UNINIT;
			}
			else {
				CurrSSA = this->SSAStack.at(GlobIndex).back();  // fetch from top of stack
			}
			SMPPhiFunction TempPhi = (*CurrPhi);
			TempPhi.SetSSARef(ListPos, CurrSSA);
			TempPhiList.push_back(TempPhi);
			if (DumpFlag && (BlockNumber >= 3) && (BlockNumber <= 4)) {
				SMP_msg("BlockNumber: %d  ListPos: %d\n", BlockNumber, ListPos);
			}
		} // end for all phi functions in successor
		// Go back through the Phi function set and replace the items that need to be updated.
		for (TempIter = TempPhiList.begin(); TempIter != TempPhiList.end(); ++TempIter) {
			if (DumpFlag && (BlockNumber >= 3) && (BlockNumber <= 4)) {
				set<SMPPhiFunction, LessPhi>::iterator FoundPhi;
				FoundPhi = (*SuccIter)->FindPhi(TempIter->GetAnyOp());
				FoundPhi->Dump();
			}
			// Use the op_t from the first phi use, because they are all the same.
			bool Erased = (*SuccIter)->ErasePhi(TempIter->GetPhiRef(0).GetOp());
			assert(Erased);
			// Now we can add back the phi function that had one SSA number changed.
			bool Added = (*SuccIter)->AddPhi(*TempIter);
			assert(Added);
			if (DumpFlag && (BlockNumber >= 3) && (BlockNumber <= 4)) {
				set<SMPPhiFunction, LessPhi>::iterator FoundPhi;
				FoundPhi = (*SuccIter)->FindPhi(TempIter->GetAnyOp());
				FoundPhi->Dump();
			}
		}
		TempPhiList.clear();
	} // end for all successors of CurrBlock
	if (DumpFlag) SMP_msg("Processed successor phi functions.\n");

	// For each successor in the dominator tree, recurse.
	list<int>::iterator ChildIter;
	for (ChildIter = this->DomTree[BlockNumber].second.begin();
		ChildIter != this->DomTree[BlockNumber].second.end();
		++ChildIter) {
			this->SSARename(*ChildIter);
	}
	if (DumpFlag) SMP_msg("Finished recursion.\n");

	// Pop off all SSAStack entries pushed during this block. I.e. for each global name,
	//  pop its SSAStack once per DEF and once per phi function in this block.
	for (CurrPhi = CurrBlock->GetFirstPhi(); CurrPhi != CurrBlock->GetLastPhi(); ++CurrPhi) {
		GlobalNameIndex = CurrPhi->GetIndex();
		this->SSAStack.at((size_t) GlobalNameIndex).pop_back();
	}
	if (DumpFlag) SMP_msg("Popped off entries due to phi functions.\n");
	for (InstIter = CurrBlock->GetFirstInstr(); InstIter != CurrBlock->GetLastInstr(); ++InstIter) {
		set<DefOrUse, LessDefUse>::iterator CurrDef;
		CurrInst = (*InstIter);
		for (CurrDef = CurrInst->GetFirstDef(); CurrDef != CurrInst->GetLastDef(); ++CurrDef) {
			// See if DEF is a global name.
			set<op_t, LessOp>::iterator GlobIter = this->GlobalNames.find(CurrDef->GetOp());
			if (GlobIter != this->GlobalNames.end()) { // found it
				unsigned int GlobIndex = ExtractGlobalIndex(*GlobIter);
				this->SSAStack.at((size_t) GlobIndex).pop_back();
			}
		} //  end for all DEFs
	} // end for all instructions
		SMP_msg("Popped off entries due to instructions.\n");

	return;
} // end of SMPFunction::SSARename()

// Main driver of SSA subscript renumbering.
void SMPFunction::SSARenumber(void) {
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#if 0
	DumpFlag |= (0 == strcmp("_IO_sputbackc", this->GetFuncName()));
#endif

	if (0 >= this->GlobalNames.size())
		return;  // no names to renumber

	// Initialize stacks and counters of SSA numbers.
	size_t GlobIndex;
	assert(0 == this->SSACounter.size());
	for (GlobIndex = 0; GlobIndex < this->GlobalNames.size(); ++GlobIndex) {
		list<int> DummyList;
		this->SSACounter.push_back(0);
		this->SSAStack.push_back(DummyList);
	}
	// Recurse through the dominator tree starting with node 0.
	this->SSARename(0);
} // end of SMPFunction::SSARenumber()

// Emit debugging output for analyzing time spent in InferTypes() ?
#define SMP_ANALYZE_INFER_TYPES_TIME 0

// Main driver for the type inference system.
void SMPFunction::InferTypes(bool FirstIter) {
	// The type inference system is an iteration over four analysis steps, until
	//  a fixed point is reached:
	// 1) Within an instruction, set types of operators based on the operator type,
	//     the operand types, and the instruction type category, and propagate the
	//     type of the SMP_ASSIGN operator to its DEF.
	// 2) Propagate the type of a DEF along its SSA chain to all USEs of that SSA name.
	// 3) If all USEs of an SSA name have the same type, but the DEF has no type,
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	//     then infer that the DEF must have the same type.
	// 4) If all references to a memory location have the same type, mark that memory
	//     location as having that type, if no aliasing occurs.
	//
	// The type inference system will mark DEFs and USEs in each instruction's DEF and USE
	//  sets with an inferred type. This inference on USEs is not conclusive for other USEs
	//  outside of that instruction. For example, a pointer could be read in from memory
	//  and used as a pointer, then hashed using an arithmetic operation. If the arithmetic
	//  operation always treats its source operands as NUMERIC and produces a NUMERIC
	//  result, e.g. SMP_BITWISE_XOR, then the USE of that pointer is NUMERIC within
	//  this xor instruction. If the DEF at the beginning of the SSA chain for the pointer
	//  is eventually marked as POINTER, then all USEs in the chain will be marked POINTER
	//  as well (see step 2 above). This inconsistency along the USE chain is perfectly
	//  acceptable in our type system. It is important to mark the USEs according to how
	//  we observe them being used, because consistent USEs will propagate back up to
	//  the DEF in step 3 above.

	bool changed;
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	bool NewChange = false;
#if SMP_ANALYZE_INFER_TYPES_TIME
	bool DebugFlag2 = false;
	DebugFlag2 |= (0 == strcmp("Option", this->GetFuncName()));
	long NewChangeCount;
	long IterationCount = 0;
#endif
#if SMP_DEBUG_TYPE_INFERENCE
	DebugFlag |= (0 == strcmp("__libc_csu_init", this->GetFuncName()));
	list<SMPInstr *>::iterator InstIter;
	SMPInstr *CurrInst;
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	set<DefOrUse, LessDefUse>::iterator CurrDef;
	set<DefOrUse, LessDefUse>::iterator NextDef;
	list<SMPBasicBlock *>::iterator BlockIter;
	SMPBasicBlock *CurrBlock;
	if (DebugFlag) {
		this->Dump();
	}
	// One time only: Set the types of immediate values, flags register, stack and frame
	//  pointers, and floating point registers.
		for (InstIter = this->Instrs.begin(); InstIter != this->Instrs.end(); ++InstIter) {
			CurrInst = (*InstIter);
				SMP_msg("SetImmedTypes for inst at %x: %s\n", CurrInst->GetAddr(), CurrInst->GetDisasm());
			CurrInst->SetImmedTypes(this->UseFP);
			// Infer signedness, bit width, and other info from the nature of the instruction
			//  (e.g. loads from stack locations whose signedness has been inferred earlier
			//  in FindOutGoingArgSize(), or inherently signed arithmetic opcodes like signed
			//  or unsigned multiplies and divides).
			CurrInst->MDSetWidthSignInfo(this->UseFP);
		}
		// Check for signedness inferences from conditional branches at the end of blocks.
		for (BlockIter = this->Blocks.begin(); BlockIter != this->Blocks.end(); ++BlockIter) {
			CurrBlock = (*BlockIter);
			CurrBlock->MarkBranchSignedness();
	// Iterate until no more changes: set types in DEF and USE lists based on RTL
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	//  operators and the instruction category, SSA DEF-USE chains, etc.
#if SMP_ANALYZE_INFER_TYPES_TIME
		if (DebugFlag2)
			++IterationCount;
#endif
#if SMP_ANALYZE_INFER_TYPES_TIME
			if (DebugFlag2)
				NewChangeCount = 0;
#endif
			// Step one: Infer types within instructions, context free.
			// Step two, propagating DEF types to all USEs, happens within step one
			//  whenever a DEF type is set for the first time.
			for (InstIter = this->Instrs.begin(); InstIter != this->Instrs.end(); ++InstIter) {
				CurrInst = (*InstIter);
				if (DebugFlag) SMP_msg("Inferring types for %s\n", CurrInst->GetDisasm());
				NewChange = CurrInst->InferTypes();
				changed = (changed || NewChange);
#if SMP_ANALYZE_INFER_TYPES_TIME
				if (DebugFlag2 && NewChange) {
					ea_t InstAddr = CurrInst->GetAddr();
#endif
			}
#if SMP_ANALYZE_INFER_TYPES_TIME
			if (DebugFlag2) {
				SMP_msg(" InferTypes iteration: %ld NewChangeCount: %ld \n", IterationCount, NewChangeCount);
		if (DebugFlag) SMP_msg("Finished type inference steps 1 and 2.\n");
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		// Step three: If all USEs of an SSA name have the same type, but the DEF has no
		//  type, then infer that the DEF must have the same type.
		this->TypedDefs = 0;
		this->UntypedDefs = 0;
		this->TypedPhiDefs = 0;
		this->UntypedPhiDefs = 0;
		// This step of the type inference might converge faster if we used a reverse iterator
		//  to go through the instructions, because we could infer a DEF, propagate it to
		//  the right hand side by making SMPInstr::InferOperatorType() public and calling it
		//  on the SMP_ASSIGN operator after we set the type of the left hand side (DEF). Any
		//  additional DEF inferences would be triggered mostly in the upwards direction by
		//  setting the type of one or more USEs in the current instruction. How much time gain
		//  could be achieved by doing this sequence is questionable.  !!!!****!!!!****
		for (InstIter = this->Instrs.begin(); InstIter != this->Instrs.end(); ++InstIter) {
			CurrInst = (*InstIter);
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			// Find any DEF that still has type UNINIT.
			CurrDef = CurrInst->GetFirstDef();
			while (CurrDef != CurrInst->GetLastDef()) {
				// Set erase() and insert() are needed to change types of DEFs, so
				//  get hold of the next iterator value now.
				NextDef = CurrDef;
				++NextDef;
				if (UNINIT != CurrDef->GetType()) {
					++(this->TypedDefs);
				}
				else {
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					op_t DefOp = CurrDef->GetOp();
					bool MemDef = (DefOp.type != o_reg);
					bool AliasedMemWrite = (MemDef && CurrDef->HasIndirectWrite());
					++(this->UntypedDefs);
					if (MDIsIndirectMemoryOpnd(DefOp, this->UseFP)  // relax this?
						|| (o_mem == DefOp.type)
						// Don't want to infer along DEF-USE chains for indirect
						//  memory accesses until we have alias analysis.
						++CurrDef;
						continue;
					}
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					ea_t DefAddr = CurrInst->GetAddr();
					// Call inference method based on whether it is a block-local
					//  name or a global name.
					CurrBlock = CurrInst->GetBlock();
					if (CurrBlock->IsLocalName(DefOp)) {
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						set<op_t, LessOp>::iterator NameIter;
						NameIter = CurrBlock->FindLocalName(DefOp);
						assert(CurrBlock->GetLastLocalName() != NameIter);
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						unsigned int LocIndex = ExtractGlobalIndex(*NameIter);
						NewChange = CurrBlock->InferLocalDefType(DefOp, LocIndex, DefAddr);
						if (NewChange) {
							--(this->UntypedDefs);
							++(this->TypedDefs);
						}
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						changed = (changed || NewChange);
					}
					else {
						// global name
						bool CallInst = ((CALL == CurrInst->GetDataFlowType())
							|| (INDIR_CALL == CurrInst->GetDataFlowType()));
						SMPOperandType DefType = UNINIT;
						DefType = this->InferGlobalDefType(DefOp,
							CurrDef->GetSSANum(), CurrBlock, CallInst, DefAddr);
						if (IsNotEqType(UNINIT, DefType)) {
							CurrDef = CurrInst->SetDefType(DefOp, DefType);
							--(this->UntypedDefs);
							++(this->TypedDefs);
							NewChange = true;
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						changed = (changed || NewChange);
					} // end if local name ... else ...
				} // end if (UNINIT != CurrDef->GetType()) .. else ...
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				CurrDef = NextDef;
			} // end while all DEFs in the DEF set
		} // end for all instructions
		if (DebugFlag) SMP_msg("Finished type inference step 3.\n");
		for (BlockIter = this->Blocks.begin(); BlockIter != this->Blocks.end(); ++BlockIter) {
			CurrBlock = (*BlockIter);
			changed |= CurrBlock->InferAllPhiDefTypes();
		if (DebugFlag) SMP_msg("Finished unconditional phi type inference.\n");

#if SMP_CONDITIONAL_TYPE_PROPAGATION
		if (!changed) { // Try conditional type propagation
			changed |= this->ConditionalTypePropagation();
#if SMP_DEBUG_TYPE_INFERENCE
			if (DebugFlag) {
				SMP_msg("changed = %d after conditional type propagation.\n", changed);
	} while (changed);
	// With type inference finished, infer signedness from the types, e.g.
	//  POINTER and CODEPOINTER types must be UNSIGNED.
	if (FirstIter) { // Don't want profiler-dependent signedness in the system yet.
		for (InstIter = this->Instrs.begin(); InstIter != this->Instrs.end(); ++InstIter) {
			(*InstIter)->InferSignednessFromSMPTypes(this->UsesFramePointer());
	// Record the meet of all register types that reach RETURN instructions.
	this->MDFindReturnTypes();
	return;
} // end of SMPFunction::InferTypes()
// determine signedness and width info for all operands
void SMPFunction::InferFGInfo(void) {
	bool changed, NewChange;
	unsigned short IterCount = 0;
	list<SMPInstr *>::iterator InstIter;
	list<SMPBasicBlock *>::iterator BlockIter;
	SMPBasicBlock *CurrBlock;
		for (InstIter = this->Instrs.begin(); InstIter != this->Instrs.end(); ++InstIter) {
			SMPInstr *CurrInst = (*InstIter);
			NewChange = CurrInst->InferFGInfo(IterCount);
			changed = (changed || NewChange);
		}
			for (BlockIter = this->Blocks.begin(); BlockIter != this->Blocks.end(); ++BlockIter) {
				CurrBlock = (*BlockIter);
	} while (changed);
	return;
} // end of SMPFunction::InferFGInfo()

// Apply the profiler information to this function once we've inferred everything we can about it.
void SMPFunction::ApplyProfilerInformation(ProfilerInformation* pi)
{
	assert(pi);

	// If no profiler annotations are available, save time.
	if (0 == pi->GetProfilerAnnotationCount())
		return;

	list<SMPInstr *>::iterator InstIter;
	set<DefOrUse, LessDefUse>::iterator CurrDef, NextDef;
	
	bool DebugFlag = false;
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#if SMP_DEBUG_PROFILED_TYPE_INFERENCE
	DebugFlag |= (0 == strcmp("dohanoi", this->GetFuncName()));
#endif

	// for each instruction in this function 
	for (InstIter = this->Instrs.begin(); InstIter != this->Instrs.end(); ++InstIter) {
		SMPInstr *CurrInst = (*InstIter);
		// lookup whether a load at this instruction was profiled as always numeric 
		InstructionInformation* ii = pi->GetInfo(CurrInst->GetAddr());
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		if (ii && DebugFlag)
			SMP_msg("Found instruction information for %x\n", CurrInst->GetAddr());
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		if (ii && ii->isNumeric()) {
#if SMP_DEBUG_PROFILED_TYPE_INFERENCE
			SMP_msg("Found instruction information for %x and it's numeric!\n", CurrInst->GetAddr());
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#endif
			CurrInst->UpdateMemLoadTypes((SMPOperandType)(NUMERIC|PROF_BASE));
		}

		// lookup whether this instruction has been profiled as an indirect call
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		set<ea_t> indirect_call_targets = pi->GetIndirectCallTargets(CurrInst->GetAddr());
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		for (set<ea_t>::iterator ict_iter = indirect_call_targets.begin();
			ict_iter != indirect_call_targets.end();
			++ict_iter)
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			ea_t target = *ict_iter;
			if (vector_exists(target, IndirectCallTargets))
				IndirectCallTargets.push_back(target);
			if (vector_exists(target, AllCallTargets))
				AllCallTargets.push_back(target);

		}

}	// end of SMPFunction::ApplyProfilerInformation

// For the UNINIT type DEF DefOp, see if all its USEs have a single type.
//  If so, set the DEF to that type and return type,
//  else return UNINIT.
// If DefAddr == BADADDR, then the DEF is in a Phi function, not an instruction.
SMPOperandType SMPFunction::InferGlobalDefType(op_t DefOp, int SSANum, SMPBasicBlock *DefBlock, bool CallInst, ea_t DefAddr) {
	bool DebugFlag = false;
	bool FoundNumeric = false;
	bool FoundPointer = false;
	bool FoundUnknown = false;
	bool FoundUninit = false;
#if SMP_DEBUG_TYPE_INFERENCE
	DebugFlag |= (0 == strcmp("mem_init", this->GetFuncName()));
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	if (DebugFlag) {
		SMP_msg("InferGlobalDefType for SSANum %d of ", SSANum);
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		PrintOperand(DefOp);
	list<SMPInstr *>::iterator InstIter;
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	assert(0 <= SSANum);
	set<DefOrUse, LessDefUse>::iterator CurrUse, CurrDef;
	// Go through all instructions in the block and find the instructions
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	//  that have USEs of DefOp with SSANum. If all USEs in the chain have
	//  a single type (other than UNINIT), change the DEF type to match the
	//  USE type and set changed to true.
	SMPOperandType UseType = UNINIT;
	SMPOperandType PtrType = UNINIT;
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	if (BADADDR == DefAddr) { // DEF is in a Phi function
		FoundDEF = true;
	}
	else { // DEF is in an instruction
		FoundDEF = false; // need to see the DefAddr first
	}

	for (InstIter = DefBlock->GetFirstInstr(); InstIter != DefBlock->GetLastInstr(); ++InstIter) {
		SMPInstr *CurrInst = (*InstIter);
		if ((!FoundDEF) && (DefAddr == CurrInst->GetAddr())) {
			FoundDEF = true;
		}
		else if (FoundDEF) {
			CurrDef = CurrInst->FindDef(DefOp);
			if (CurrDef != CurrInst->GetLastDef()) {
				// Found re-DEF of DefOp.
				DefEscapes = false;
			}
		}
		CurrUse = CurrInst->FindUse(DefOp);
		if (CurrUse != CurrInst->GetLastUse()) { // found a USE of DefOp
			if (CurrUse->GetSSANum() == SSANum) { // matched SSA number
				UseType = CurrUse->GetType();
				FoundNumeric |= (IsNumeric(UseType));
				FoundUnknown |= (IsUnknown(UseType));
				FoundUninit |= (IsEqType(UNINIT, UseType));
				if (IsDataPtr(UseType)) {
					if (FoundPointer) {
						if (IsNotEqType(PtrType, UseType)) {
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#if SMP_DEBUG_TYPE_INFERENCE
							SMP_msg("WARNING: Differing ptr types in global chain:");
							SMP_msg(" Prev: %d Current: %d %s\n", PtrType, UseType,
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#endif
							PtrType = POINTER;
						}
					else {
						FoundPointer = true;
						PtrType = UseType;
					}
				}
			} // end if matched SSA #
		} // end if found a USE of DefOp
	} // end for all instructions

	if (DefEscapes) { // did not find re-def
		DefEscapes = DefBlock->IsLiveOut(DefOp);
	}


	if (DefEscapes) { // Need to recurse into successor blocks
		list<SMPBasicBlock *>::iterator SuccIter;
		ea_t TempAddr;
		this->ResetProcessedBlocks(); // set up recursion
		for (SuccIter = DefBlock->GetFirstSucc(); SuccIter != DefBlock->GetLastSucc(); ++SuccIter) {
			SMPBasicBlock *CurrBlock = (*SuccIter);
			set<SMPPhiFunction, LessPhi>::iterator PhiIter = CurrBlock->FindPhi(DefOp);
			TempAddr = DefAddr;
			if (PhiIter != CurrBlock->GetLastPhi()) {
				TempAddr = BADADDR;  // signals that DefOp will get re-DEFed in a Phi function.
			}
			else if (BADADDR == TempAddr) { // was BADADDR coming in to this function
				// We don't want to pass BADADDR down the recursion chain, because it will be interpreted
				//  by each successor block to mean that DefOp was a Phi USE that got re-DEFed in a Phi function
				//  within itself. Pass the dummy address that indicates LiveIn to the block.
				TempAddr = CurrBlock->GetFirstAddr() - 1;
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			}
			// Should we screen the recursive call below using CurrBlock->IsLiveIn(DefOp) for speed?  !!!!****!!!!
			CurrBlock->InferGlobalDefType(DefOp, SSANum, TempAddr, FoundNumeric, FoundPointer, FoundUnknown, FoundUninit, PtrType);
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	}
	// Do we have a consistent type?
	// If we see any definite POINTER uses, we must set the DEF
	//  to type POINTER or a refinement of it.
	if (FoundPointer)
		UseType = PtrType;
	else if (FoundNumeric && !FoundUninit && !FoundUnknown)
		UseType = NUMERIC;
	else
		return UNINIT; // no POINTER, but no consistent type

	assert(UNINIT != UseType);
	if (DebugFlag) SMP_msg("Inferring global DEF of type %d\n", UseType);