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/*
 * SMPFunction.cpp - <see below>.
 *
 * Copyright (c) 2000, 2001, 2010 - University of Virginia 
 *
 * This file is part of the Memory Error Detection System (MEDS) infrastructure.
 * This file may be used and modified for non-commercial purposes as long as 
 * all copyright, permission, and nonwarranty notices are preserved.  
 * Redistribution is prohibited without prior written consent from the University 
 * of Virginia.
 *
 * Please contact the authors for restrictions applying to commercial use.
 *
 * THIS SOURCE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Author: University of Virginia
 * e-mail: jwd@virginia.com
 * URL   : http://www.cs.virginia.edu/
 *
 * Additional copyrights 2010, 2011 by Zephyr Software LLC
 * e-mail: {clc,jwd}@zephyr-software.com
 * URL   : http://www.zephyr-software.com/
 *
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 */

//
// SMPFunction.cpp
//
// This module performs the fundamental data flow analyses needed for the
//   SMP project (Software Memory Protection) at the function level.
//

#include <list>
#include <set>
#include <vector>
#include <algorithm>

#include <cstring>

#include <pro.h>
#include <assert.h>
#include <ida.hpp>
#include <idp.hpp>
#include <auto.hpp>
#include <bytes.hpp>
#include <funcs.hpp>
#include <allins.hpp>
#include <intel.hpp>
#include <name.hpp>

#include "SMPDataFlowAnalysis.h"
#include "SMPStaticAnalyzer.h"
#include "SMPFunction.h"
#include "SMPBasicBlock.h"
#include "SMPInstr.h"

// Set to 1 for debugging output
#define SMP_DEBUG 1
#define SMP_DEBUG2 0   // verbose
#define SMP_DEBUG3 0   // verbose
#define SMP_DEBUG_CONTROLFLOW 0  // tells what processing stage is entered
#define SMP_DEBUG_XOR 0
#define SMP_DEBUG_CHUNKS 1  // tracking down tail chunks for functions
#define SMP_DEBUG_FRAMEFIXUP 0
#define SMP_DEBUG_DATAFLOW 0
#define SMP_DEBUG_DATAFLOW_VERBOSE 0
#define SMP_DEBUG_TYPE_INFERENCE 0
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#define SMP_DEBUG_PROFILED_TYPE_INFERENCE 0
#define SMP_DEBUG_STACK_GRANULARITY 0
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#define SMP_DEBUG_FUNC 0
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#define SMP_VERBOSE_DEBUG_FUNC 0
#define SMP_DEBUG_BUILD_RTL 1   // leave this on; serious errors reported
#define SMP_DEBUG_UNINITIALIZED_SSA_NAMES 1
#define SMP_WARN_UNUSED_DEFS 0
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#define SMP_DEBUG_SWITCH_TABLE_INFO 0
#define SMP_OPTIMIZE_BLOCK_PROFILING 0

// Compute LVA/SSA or not? Turn it off for NICECAP demo on 31-JAN-2008
// Compute fine-grained stack boundaries?
#define SMP_COMPUTE_STACK_GRANULARITY 1
// Insert a floating no-op instruction at top of each function to hold SSA DEFs
//  of LiveIn names?
#define SMP_USE_SSA_FNOP_MARKER 1

// Use conditional type propagation on phi functions
#define SMP_CONDITIONAL_TYPE_PROPAGATION 0

// Kludges to fix IDA Pro 5.2 errors in cc1.ncexe
#define SMP_IDAPRO52_WORKAROUND 0

// Basic block number 0 is the top of the CFG lattice.
#define SMP_TOP_BLOCK 0 

// Set SharedTailChunks to TRUE for entire printf family
//  After we restructure the parent/tail structure of the database, this
//  will go away.
#define KLUDGE_VFPRINTF_FAMILY 1

// Used for binary search by function number in SMPStaticAnalyzer.cpp
//  to trigger debugging output and find which instruction in which
//  function is causing a crash.
bool SMPBinaryDebug = false;

using namespace std;


// helper function to determine if an object is in a vector
template <class T>	
bool vector_exists(const T &item, const vector<T> &vec) {
	for (size_t i = 0; i < vec.size(); ++i) {
		if (vec[i] == item)
			return true;
	}
	return false;
}

// *****************************************************************
// Class SMPFunction
// *****************************************************************

// Constructor
SMPFunction::SMPFunction(func_t *Info, SMPProgram* pgm) {
	this->FuncInfo = *Info;
	this->FuncName[0] = '\0';
	this->BlockCount = 0;
	this->UseFP = false;
	this->StaticFunc = false;
	this->LibFunc = false;
	this->IndirectCalls = false;
	this->UnresolvedIndirectCalls = false;
	this->IndirectJumps = false;
	this->UnresolvedIndirectJumps = false;
	this->SharedChunks = false;
	this->CallsAlloca = false;
	this->BuiltRTLs = false;
	this->SpecSafeFunc = false;
	this->SafeCallee = false;
	this->SpecSafeCallee = false;
	this->SafeFunc = true;
	this->SpecSafeFunc = true;
	this->SafeCallee = true;
	this->SpecSafeCallee = true;
#endif
	this->NeedsStackReferent = true;
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	this->SpecNeedsStackReferent = true;
	this->HasIndirectWrites = false;
	this->OutgoingArgsComputed = false;
	this->OutgoingArgsSize = 0;
	this->TypedDefs = 0;
	this->UntypedDefs = 0;
	this->TypedPhiDefs = 0;
	this->UntypedPhiDefs = 0;
	this->SafeBlocks = 0;
	this->UnsafeBlocks = 0;
	this->Size = 0;
	this->LocalVarsSize = 0;
	this->CalleeSavedRegsSize = 0;
	this->RetAddrSize = 0;
	this->IncomingArgsSize = 0;
	this->OutgoingArgsSize = 0;
	this->LocalVarsAllocInstr = BADADDR;
	this->LocalVarsDeallocInstr = BADADDR;
	this->AllocPointDelta = 0;
	this->MinStackDelta = 0;
	this->LocalVarOffsetLimit = 0;

	this->ReturnAddrStatus = FUNC_UNKNOWN;
	this->SetIsSpeculative(false);

	this->Instrs.clear();
	this->Blocks.clear();
	this->DirectCallTargets.clear();
	this->IndirectCallTargets.clear();
	this->AllCallTargets.clear();
	this->InstBlockMap.clear();
	this->RPOBlocks.clear();
	this->IDom.clear();
	this->DomTree.clear();
	this->GlobalNames.clear();
	this->BlocksDefinedIn.clear();
	this->SSACounter.clear();
	this->SSAStack.clear();
	this->LocalVarTable.clear();
	this->StackFrameMap.clear();
	this->FineGrainedStackTable.clear();
	this->SavedRegLoc.clear();
	this->ReturnRegTypes.clear();
	this->LiveInSet.clear();
	this->LiveOutSet.clear();
	this->KillSet.clear();
	this->GlobalDefAddrBySSA.clear();

	for (int RegIndex = R_ax; RegIndex <= R_di; ++RegIndex) {
		this->SavedRegLoc.push_back(0); // zero offset means reg not saved
		this->ReturnRegTypes.push_back(UNINIT);
	}

} // end of SMPFunction() constructor
// Get a non-stale pointer to the func_t info for the current function.
func_t *SMPFunction::GetFuncInfo(void) {
	func_t *myPtr = get_func(this->FirstEA);
	assert(NULL != myPtr);
	return myPtr;
}

// Reset the Processed flags in all blocks to false.
void SMPFunction::ResetProcessedBlocks(void) {
	list<SMPBasicBlock>::iterator CurrBlock;
	for (CurrBlock = this->Blocks.begin(); CurrBlock != this->Blocks.end(); ++CurrBlock) {
		CurrBlock->SetProcessed(false);
	}
	return;
} // end of SMPFunction::ResetProcessedBlocks()

// Return an iterator for the beginning of the LiveInSet. 
set<op_t, LessOp>::iterator SMPFunction::GetFirstLiveIn(void) {
	return this->LiveInSet.begin();
} // end of SMPBasicBlock::GetFirstLiveIn()

// Get termination iterator marker for the LiveIn set, for use by predecessors.
set<op_t, LessOp>::iterator SMPFunction::GetLastLiveIn(void) {
	return this->LiveInSet.end();
}

// Get iterator for the start of the LiveOut set.
set<op_t, LessOp>::iterator SMPFunction::GetFirstLiveOut(void) {
	return this->LiveOutSet.begin();
}

// Get termination iterator marker for the LiveOut set.
set<op_t, LessOp>::iterator SMPFunction::GetLastLiveOut(void) {
	return this->LiveOutSet.end();
}

// Get iterator for the start of the VarKill set.
set<op_t, LessOp>::iterator SMPFunction::GetFirstVarKill(void) {
	return this->KillSet.begin();
}

// Get termination iterator marker for the VarKill set.
set<op_t, LessOp>::iterator SMPFunction::GetLastVarKill(void) {
	return this->KillSet.end();
}

// Four methods to get values from the maps of global reg/SSA to FG info.
//  For local names, see corresponding methods in SMPBasicBlock.
unsigned short SMPFunction::GetDefSignMiscInfo(int DefHashValue) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalDefFGInfoBySSA.find(DefHashValue);
	if (MapIter != this->GlobalDefFGInfoBySSA.end())
		return MapIter->second.SignMiscInfo;
	else
		return 0;
} // end of SMPFunction::GetDefSignMiscInfo()

unsigned short SMPFunction::GetUseSignMiscInfo(int UseHashValue) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalUseFGInfoBySSA.find(UseHashValue);
	if (MapIter != this->GlobalUseFGInfoBySSA.end())
		return MapIter->second.SignMiscInfo;
	else
		return 0;
} // end of SMPFunction::GetUseSignMiscInfo()

unsigned short SMPFunction::GetDefWidthTypeInfo(int DefHashValue) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalDefFGInfoBySSA.find(DefHashValue);
	if (MapIter != this->GlobalDefFGInfoBySSA.end())
		return MapIter->second.SizeInfo;
	else
		return 0;
} // end of SMPFunction::GetDefWidthTypeInfo()

unsigned short SMPFunction::GetUseWidthTypeInfo(int UseHashValue) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalUseFGInfoBySSA.find(UseHashValue);
	if (MapIter != this->GlobalUseFGInfoBySSA.end())
		return MapIter->second.SizeInfo;
	else
		return 0;
} // end of SMPFunction::GetUseWidthTypeInfo()

// Add a caller to the list of all callers of this function.
void SMPFunction::AddCallSource(ea_t addr) {
	// Convert call instruction address to beginning address of the caller.
	func_t *FuncInfo = get_func(addr);
	if (NULL == FuncInfo) {
		msg("SERIOUS WARNING: Call location %x not in a function.\n", addr);
		return;
	}
	ea_t FirstAddr = FuncInfo->startEA;
	assert(BADADDR != FirstAddr);
	this->AllCallSources.insert(FirstAddr);
	return;
} // end of SMPFunction::AddCallSource()

// Four methods to get values into the maps of global reg/SSA to FG info.
//  For local names, see corresponding methods in SMPBasicBlock.
void SMPFunction::UpdateDefSignMiscInfo(int DefHashValue, unsigned short NewInfo) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalDefFGInfoBySSA.find(DefHashValue);
	if (MapIter == this->GlobalDefFGInfoBySSA.end()) {
		// Not found; insert first.
		struct FineGrainedInfo NewFGInfo;
		NewFGInfo.SignMiscInfo = NewInfo;
		NewFGInfo.SizeInfo = 0;
		pair<int, struct FineGrainedInfo> MapItem(DefHashValue, NewFGInfo);
		MapResult = this->GlobalDefFGInfoBySSA.insert(MapItem);
		assert(MapResult.second); // Was not previously found, insertion must work.
	}
	else { // found; just OR in the new bits.
		MapIter->second.SignMiscInfo |= NewInfo;
	}

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

void SMPFunction::UpdateUseSignMiscInfo(int UseHashValue, unsigned short NewInfo) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalUseFGInfoBySSA.find(UseHashValue);
	if (MapIter == this->GlobalUseFGInfoBySSA.end()) {
		// Not found; insert first.
		struct FineGrainedInfo NewFGInfo;
		NewFGInfo.SignMiscInfo = NewInfo;
		NewFGInfo.SizeInfo = 0;
		pair<int, struct FineGrainedInfo> MapItem(UseHashValue, NewFGInfo);
		MapResult = this->GlobalUseFGInfoBySSA.insert(MapItem);
		assert(MapResult.second); // Was not previously found, insertion must work.
	}
	else { // found; just OR in the new bits.
		MapIter->second.SignMiscInfo |= NewInfo;
	}

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

void SMPFunction::UpdateDefWidthTypeInfo(int DefHashValue, unsigned short NewInfo) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalDefFGInfoBySSA.find(DefHashValue);
	if (MapIter == this->GlobalDefFGInfoBySSA.end()) {
		// Not found; insert first.
		struct FineGrainedInfo NewFGInfo;
		NewFGInfo.SignMiscInfo = 0;
		NewFGInfo.SizeInfo = NewInfo;
		pair<int, struct FineGrainedInfo> MapItem(DefHashValue, NewFGInfo);
		MapResult = this->GlobalDefFGInfoBySSA.insert(MapItem);
		assert(MapResult.second); // Was not previously found, insertion must work.
	}
	else { // found; just OR in the new bits.
		MapIter->second.SizeInfo |= NewInfo;
	}

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

void SMPFunction::UpdateUseWidthTypeInfo(int UseHashValue, unsigned short NewInfo) {
	map<int, struct FineGrainedInfo>::iterator MapIter;
	pair<map<int, struct FineGrainedInfo>::iterator, bool> MapResult;

	MapIter = this->GlobalUseFGInfoBySSA.find(UseHashValue);
	if (MapIter == this->GlobalUseFGInfoBySSA.end()) {
		// Not found; insert first.
		struct FineGrainedInfo NewFGInfo;
		NewFGInfo.SignMiscInfo = 0;
		NewFGInfo.SizeInfo = NewInfo;
		pair<int, struct FineGrainedInfo> MapItem(UseHashValue, NewFGInfo);
		MapResult = this->GlobalUseFGInfoBySSA.insert(MapItem);
		assert(MapResult.second); // Was not previously found, insertion must work.
	}
	else { // found; just OR in the new bits.
		MapIter->second.SizeInfo |= NewInfo;
	}

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

// Figure out the different regions of the stack frame, and find the
//  instructions that allocate and deallocate the local variables space
//  on the stack frame.
// The stack frame info will be used to emit stack
//  annotations when Analyze() reaches the stack allocation
//  instruction that sets aside space for local vars.
// Set the address of the instruction at which these
//  annotations should be emitted. This should normally
//  be an instruction such as:  sub esp,48
//  However, for a function with no local variables at all,
//  we will need to determine which instruction should be
//  considered to be the final instruction of the function
//  prologue and return its address.
// Likewise, we find the stack deallocating instruction in
//  the function epilogue.
void SMPFunction::SetStackFrameInfo(void) {
	bool FoundAllocInstr = false;
	bool FoundDeallocInstr = false;
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	bool DebugFlag = false;
#if SMP_DEBUG_FRAMEFIXUP
	DebugFlag |= (0 == strcmp(".init_proc", this->GetFuncName()));
#endif

	// The sizes of the three regions of the stack frame other than the
	//  return address are stored in the function structure.
	this->LocalVarsSize = this->FuncInfo.frsize;
	this->CalleeSavedRegsSize = this->FuncInfo.frregs;
	this->IncomingArgsSize = this->FuncInfo.argsize;

	// The return address size can be obtained in a machine independent
	//  way by calling get_frame_retsize(). 
	this->RetAddrSize = get_frame_retsize(this->GetFuncInfo());

	// IDA Pro has trouble with functions that do not have any local
	//  variables. Unfortunately, the C library has plenty of these
	//  functions. IDA usually claims that frregs is zero and frsize
	//  is N, when the values should have been reversed. We can attempt
	//  to detect this and fix it.
	bool FrameInfoFixed = this->MDFixFrameInfo();
#if SMP_DEBUG_CONTROLFLOW
	msg("Returned from MDFixFrameInfo()\n");
#endif
#if SMP_DEBUG_FRAMEFIXUP
	if (FrameInfoFixed) {
		msg("Fixed stack frame size info: %s\n", this->FuncName);
		SMPBasicBlock CurrBlock = this->Blocks.front();
		msg("First basic block:\n");
		for (list<list<SMPInstr>::iterator>::iterator CurrInstr = CurrBlock.GetFirstInstr();
			CurrInstr != CurrBlock.GetLastInstr();
			++CurrInstr) {
			msg("%s\n", (*CurrInstr)->GetDisasm());
		}
	}
#endif

	// Now, if LocalVarsSize is not zero, we need to find the instruction
	//  in the function prologue that allocates space on the stack for
	//  local vars. This code could be made more robust in the future
	//  by matching LocalVarsSize to the immediate value in the allocation
	//  instruction. However, IDA Pro is sometimes a little off on this
	//  number. **!!**
	if (0 < this->LocalVarsSize) {
		if (DebugFlag) msg("Searching for alloc and dealloc\n");
		for (list<SMPInstr>::iterator CurrInstr = this->Instrs.begin();
			CurrInstr != this->Instrs.end();
			++CurrInstr) {

#if SMP_USE_SSA_FNOP_MARKER
			if (this->Instrs.begin() == CurrInstr)
				continue;  // skip marker instruction
#endif

			ea_t addr = CurrInstr->GetAddr();

			// Keep the most recent instruction in the DeallocInstr
			//  in case we reach the return without seeing a dealloc.
			if (!FoundDeallocInstr) {
				this->LocalVarsDeallocInstr = addr;
			}

			if (!FoundAllocInstr
				&& CurrInstr->MDIsFrameAllocInstr()) {
#if SMP_DEBUG_CONTROLFLOW
				msg("Returned from MDIsFrameAllocInstr()\n");
#endif
				this->LocalVarsAllocInstr = addr;
				FoundAllocInstr = true;
				if (DebugFlag) msg("Found alloc: %s\n", CurrInstr->GetDisasm());
				// As soon as we have found the local vars allocation,
				//  we can try to fix incorrect sets of UseFP by IDA.
				// NOTE: We might want to extend this in the future to
				//  handle functions that have no locals.  **!!**
				bool FixedUseFP = MDFixUseFP();
#if SMP_DEBUG_CONTROLFLOW
				msg("Returned from MDFixUseFP()\n");
#endif
#if SMP_DEBUG_FRAMEFIXUP
				if (FixedUseFP) {
					msg("Fixed UseFP in %s\n", this->FuncName);
				}
#endif
			}
			else if (FoundAllocInstr) {
				// We can now start searching for the DeallocInstr.
				if (CurrInstr->MDIsFrameDeallocInstr(UseFP, this->LocalVarsSize)) {
					// Keep saving the most recent addr that looks
					//  like the DeallocInstr until we reach the
					//  end of the function. Last one to look like
					//  it is used as the DeallocInstr.
#if SMP_DEBUG_CONTROLFLOW
					msg("Returned from MDIsFrameDeallocInstr()\n");
#endif
					this->LocalVarsDeallocInstr = addr;
					FoundDeallocInstr = true;
				}
				else {
					if (DebugFlag) msg("Not dealloc: %s\n", CurrInstr->GetDisasm());
				}
			}
		} // end for (list<SMPInstr>::iterator CurrInstr ... )
		if (!FoundAllocInstr) {
			// Could not find the frame allocating instruction.  Bad.
			// See if we can find the point at which the stack allocation reaches
			//  a total of FuncInfo.frsize+frregs, regardless of whether it happened by push
			//  instructions or some other means.
			this->LocalVarsAllocInstr = this->FindAllocPoint(this->FuncInfo.frsize + this->FuncInfo.frregs);
#if SMP_DEBUG_CONTROLFLOW
			msg("Returned from FindAllocPoint()\n");
#endif
#if SMP_DEBUG_FRAMEFIXUP
			if (BADADDR == this->LocalVarsAllocInstr) {
				msg("ERROR: Could not find stack frame allocation in %s\n",
					FuncName);
				msg("LocalVarsSize: %d  SavedRegsSize: %d ArgsSize: %d\n",
					LocalVarsSize, CalleeSavedRegsSize, IncomingArgsSize);
			}
			else {
				msg("FindAllocPoint found %x for function %s\n",
					this->LocalVarsAllocInstr, this->GetFuncName());
			}
#endif
		}
#if SMP_DEBUG_FRAMEFIXUP
		if (!FoundDeallocInstr) {
			// Could not find the frame deallocating instruction.  Bad.
			// Emit diagnostic and use the last instruction in the
			// function.
			msg("ERROR: Could not find stack frame deallocation in %s\n",
				FuncName);
		}
#endif
	}
	// else LocalVarsSize was zero, meaning that we need to search 
	//  for the end of the function prologue code and emit stack frame
	//  annotations from that address (i.e. this method returns that
	//  address). We will approximate this by finding the end of the
	//  sequence of PUSH instructions at the beginning of the function.
	//  The last PUSH instruction should be the last callee-save-reg
	//  instruction. We can make this more robust in the future by
	//  making sure that we do not count a PUSH of anything other than
	//  a register. **!!**
	// NOTE: 2nd prologue instr is usually mov ebp,esp
	// THE ASSUMPTION THAT WE HAVE ONLY PUSH INSTRUCTIONS BEFORE
	// THE ALLOCATING INSTR IS ONLY TRUE WHEN LOCALVARSSIZE == 0;
	else {
		ea_t SaveAddr = this->FuncInfo.startEA;
		for (list<SMPInstr>::iterator CurrInstr = this->Instrs.begin();
			CurrInstr != this->Instrs.end();
			++CurrInstr) {
#if SMP_USE_SSA_FNOP_MARKER
			if (this->Instrs.begin() == CurrInstr)
				continue;  // skip marker instruction
#endif

			insn_t CurrCmd = CurrInstr->GetCmd();
			ea_t addr = CurrInstr->GetAddr();
			if (CurrCmd.itype == NN_push)
				SaveAddr = addr;
			else
				break;
		}
		this->LocalVarsAllocInstr = SaveAddr;
		this->LocalVarsDeallocInstr = 0;
	} // end if (LocalVarsSize > 0) ... else ...

	this->CallsAlloca = this->FindAlloca();

#if SMP_COMPUTE_STACK_GRANULARITY
	// Now, find the boundaries between local variables.
	this->BuildLocalVarTable();
#endif

	// Get callee-saved regs info for remediation use.
	if (FoundAllocInstr) {
		this->MDFindSavedRegs();
	}

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

// IDA Pro defines the sizes of regions in the stack frame in a way
//  that suits its purposes but not ours. The frsize field of the func_info_t
//  structure measures the distance between the stack pointer and the
//  frame pointer (ESP and EBP in the x86). This region includes some
//  of the callee-saved registers. So, the frregs field only includes
//  the callee-saved registers that are above the frame pointer.
//  x86 standard prologue on gcc/linux:
//    push ebp      ; save old frame pointer
//    mov ebp,esp   ; new frame pointer = current stack pointer
//    push esi      ; callee save reg
//    push edi      ; callee save reg
//    sub esp,34h   ; allocate 52 bytes for local variables
//
//  Notice that EBP acquires its final frame pointer value AFTER the
//  old EBP has been pushed. This means that, of the three callee saved
//  registers, one is above where EBP points and two are below.
//  IDA Pro is concerned with generating readable addressing expressions
//  for items on the stack. None of the callee-saved regs will ever
//  be addressed in the function; they will be dormant until they are popped
//  off the stack in the function epilogue. In order to create readable
//  disassembled code, IDA defines named constant offsets for locals. These
//  offsets are negative values (x86 stack grows downward from EBP toward
//  ESP). When ESP_relative addressing occurs, IDA converts a statement:
//    mov eax,[esp+12]
//  into the statement:
//    mov eax,[esp+3Ch+var_30]
//  Here, 3Ch == 60 decimal is the distance between ESP and EBP, and
//  var_30 is defined to have the value -30h == -48 decimal. So, the
//  "frame size" in IDA Pro is 60 bytes, and a certain local can be
//  addressed in ESP-relative manner as shown, or as [ebp+var_30] for
//  EBP-relative addressing. The interactive IDA user can then edit
//  the name var_30 to something mnemonic, such as "virus_size", and IDA
//  will replace all occurrences with the new name, so that code references
//  automatically become [ebp+virus_size]. As the user proceeds
//  interactively, he eventually produces very understandable code.
// This all makes sense for producing readable assembly text. However,
//  our analyses have a compiler perspective as well as a memory access
//  defense perspective. SMP distinguishes between callee saved regs,
//  which should not be overwritten in the function body, and local
//  variables, which can be written. We view the stack frame in logical
//  pieces: here are the saved regs, here are the locals, here is the
//  return address, etc. We don't care which direction from EBP the
//  callee-saved registers lie; we don't want to lump them in with the
//  local variables. We also don't like the fact that IDA Pro will take
//  the function prologue code shown above and declare frregs=4 and
//  frsize=60, because frsize no longer matches the stack allocation
//  statement sub esp,34h == sub esp,52. We prefer frsize=52 and frregs=12.
// So, the task of this function is to fix these stack sizes in our
//  private data members for the function, while leaving the IDA database
//  alone because IDA needs to maintain its own definitions of these
//  variables.
// Fixing means we will update the data members LocalVarsSize and
//  CalleeSavedRegsSize.
// NOTE: This function is both machine dependent and platform dependent.
//  The prologue and epilogue code generated by gcc-linux is as discussed
//  above, while on Visual Studio and other Windows x86 compilers, the
//  saving of registers other than EBP happens AFTER local stack allocation.
//  A Windows version of the function would expect to see the pushing
//  of ESI and EDI AFTER the sub esp,34h statement.
bool SMPFunction::MDFixFrameInfo(void) {
	int SavedRegsSize = 0;
	int OtherPushesSize = 0;  // besides callee-saved regs
	int NewLocalsSize = 0;
	int OldFrameTotal = this->CalleeSavedRegsSize + this->LocalVarsSize;
	bool Changed = false;
	bool DebugFlag = (0 == strcmp("__libc_csu_init", this->GetFuncName()));

	// Iterate through the first basic block in the function. If we find
	//  a frame allocating Instr in it, then we have local vars. If not,
	//  we don't, and LocalVarsSize should have been zero. Count the callee
	//  register saves leading up to the local allocation. Set data members
	//  according to what we found if the values of the data members would
	//  change.
	SMPBasicBlock CurrBlock = this->Blocks.front();
	for (list<list<SMPInstr>::iterator>::iterator CurrIter = CurrBlock.GetFirstInstr();
		CurrIter != CurrBlock.GetLastInstr();
		++CurrIter) {
#if SMP_USE_SSA_FNOP_MARKER
		if (CurrBlock.GetFirstInstr() == CurrIter)
			continue;  // skip marker instruction
#endif

		list<SMPInstr>::iterator CurrInstr = *CurrIter;
		if (CurrInstr->MDIsPushInstr()) {
			// We will make the gcc-linux assumption that a PUSH in
			//  the first basic block, prior to the stack allocating
			//  instruction, is a callee register save. To make this
			//  more robust, we ensure that the register is from
			//  the callee saved group of registers, and that it has
			//  not been defined thus far in the function (else it might
			//  be a push of an outgoing argument to a call that happens
			//  in the first block when there are no locals). **!!!!**
			if (CurrInstr->MDUsesCalleeSavedReg()
				&& !CurrInstr->HasSourceMemoryOperand()) {
				SavedRegsSize += 4; // **!!** should check the size
				if (DebugFlag) msg("libc_csu_init SavedRegsSize: %d  %s\n", SavedRegsSize,
					CurrInstr->GetDisasm());
			}
			else {
				// Pushes of outgoing args can be scheduled so that
				//  they are mixed with the pushes of callee saved regs.
				OtherPushesSize += 4;
				if (DebugFlag) msg("libc_csu_init OtherPushesSize: %d  %s\n", OtherPushesSize,
					CurrInstr->GetDisasm());
			}
		}
		else if (CurrInstr->MDIsFrameAllocInstr()) {
			if (DebugFlag) msg("libc_csu_init allocinstr: %s\n", CurrInstr->GetDisasm());
			SavedRegsSize += OtherPushesSize;
			// Get the size being allocated.
			set<DefOrUse, LessDefUse>::iterator CurrUse;
			for (CurrUse = CurrInstr->GetFirstUse(); CurrUse != CurrInstr->GetLastUse(); ++CurrUse) {
				// Find the immediate operand.
				if (o_imm == CurrUse->GetOp().type) {
					// Get its value into LocalVarsSize.
					long AllocValue = (signed long) CurrUse->GetOp().value;
					// One compiler might have sub esp,24 and another
					//  might have add esp,-24. Take the absolute value.
					if (0 > AllocValue)
						AllocValue = -AllocValue;
					if (AllocValue != (long) this->LocalVarsSize) {
						Changed = true;
#if SMP_DEBUG_FRAMEFIXUP
						if (AllocValue + SavedRegsSize != OldFrameTotal)
							msg("Total frame size changed: %s\n", this->FuncName);
#endif
						this->LocalVarsSize = (asize_t) AllocValue;
						this->CalleeSavedRegsSize = (ushort) SavedRegsSize;
						NewLocalsSize = this->LocalVarsSize;
					}
					else { // Old value was correct; no change.
						NewLocalsSize = this->LocalVarsSize;
						if (SavedRegsSize != this->CalleeSavedRegsSize) {
							this->CalleeSavedRegsSize = (ushort) SavedRegsSize;
							Changed = true;
#if SMP_DEBUG_FRAMEFIXUP
							msg("Only callee regs size changed: %s\n", this->FuncName);
#endif
						}
					}
				} // end if (o_imm == ...)
			} // end for all uses
			break; // After frame allocation instr, we are done
		} // end if (push) .. elsif frame allocating instr
	} // end for all instructions in the first basic block

	// If we did not find an allocating instruction, see if it would keep
	//  the total size the same to set LocalVarsSize to 0 and to set
	//  CalleeSavedRegsSize to SavedRegsSize. If so, do it. If not, we
	//  might be better off to leave the numbers alone.
	if (!Changed && (NewLocalsSize == 0)) {
		if (DebugFlag) msg("libc_csu_init OldFrameTotal: %d \n", OldFrameTotal);
		if (OldFrameTotal == SavedRegsSize) {
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			this->CalleeSavedRegsSize = (ushort) SavedRegsSize;
			this->LocalVarsSize = 0;
			Changed = true;
		}
#if SMP_DEBUG_FRAMEFIXUP
		else {
			msg("Could not update frame sizes: %s\n", this->FuncName);
		}
#endif
	}

#if SMP_DEBUG_FRAMEFIXUP
	if ((0 < OtherPushesSize) && (0 < NewLocalsSize))
		msg("Extra pushes found of size %d in %s\n", OtherPushesSize,
			this->FuncName);
#endif

	return Changed;
} // end of SMPFunction::MDFixFrameInfo()

// Some functions have difficult to find stack allocations. For example, in some
//  version of glibc, strpbrk() zeroes out register ECX and then pushes it more than
//  100 times in order to allocate zero-ed out local vars space for a character translation
//  table. We will use the stack pointer analysis of IDA to find out if there is a point
//  in the first basic block at which the stack pointer reaches the allocation total
//  that IDA is expecting for the local vars region.
// If so, we return the address of the instruction at which ESP reaches its value, else
//  we return BADADDR.
ea_t SMPFunction::FindAllocPoint(asize_t OriginalLocSize) {
	sval_t TargetSize = - ((sval_t) OriginalLocSize);  // negate; stack grows down 

#if SMP_DEBUG_FRAMEFIXUP
	bool DebugFlag = (0 == strcmp("_dl_runtime_resolve", this->GetFuncName()));
		msg("%s OriginalLocSize: %d\n", this->GetFuncName(), OriginalLocSize);
	if (this->AnalyzedSP) {
		// Limit our analysis to the first basic block in the function.
		list<SMPInstr>::iterator CurrInstr;
		for (CurrInstr = this->Instrs.begin(); CurrInstr != this->Instrs.end();	++CurrInstr) {
#if SMP_USE_SSA_FNOP_MARKER
			if (this->Instrs.begin() == CurrInstr)
				continue;  // skip marker instruction
#endif

			ea_t addr = CurrInstr->GetAddr();
			// get_spd() returns a cumulative delta of ESP
			sval_t sp_delta = get_spd(this->GetFuncInfo(), addr);
#if SMP_DEBUG_FRAMEFIXUP
				msg("%s delta: %d at %x\n", this->GetFuncName(), sp_delta, addr);
			if (sp_delta == TargetSize) { // <= instead of == here?  **!!**
				// Previous instruction hit the frame size.
				if (CurrInstr == this->Instrs.begin()) {
					return BADADDR;  // cannot back up from first instruction
				}
				else {
					ea_t PrevAddr = (--CurrInstr)->GetAddr();
#if SMP_USE_SSA_FNOP_MARKER
					if (this->Instrs.begin()->GetAddr() == PrevAddr)
						return BADADDR;  // don't return marker instruction
					else
						return PrevAddr;
#else
					return PrevAddr;
#endif
			if (CurrInstr->IsLastInBlock()) {
				// It could be that the current instruction will cause the stack pointer
				//  delta to reach the TargetSize. sp_delta is not updated until after the
				//  current instruction, so we need to look ahead one instruction if the
				//  current block falls through. On the other hand, if the current block
				//  ends with a jump or return, we cannot hit TargetSize.
				if (CurrInstr->IsBasicBlockTerminator())
					return BADADDR;
				list<SMPInstr>::iterator NextInstr = CurrInstr;
				++NextInstr;
				if (NextInstr == this->Instrs.end())
					return BADADDR;
				sp_delta = get_spd(this->GetFuncInfo(), NextInstr->GetAddr());
				if (sp_delta == TargetSize) {
					// CurrInstr will cause stack pointer delta to hit TargetSize.
					return addr;
				}
				else {
					return BADADDR;
				}
			} // end if LastInBlock
		} // end for all instructions
	} // end if (this->AnalyzedSP)
#if SMP_DEBUG_FRAMEFIXUP
	else {
		msg("AnalyzedSP is false for %s\n", this->GetFuncName());
	}
#endif
	return BADADDR;
} // end of SMPFunction::FindAllocPoint()

// IDA Pro is sometimes confused by a function that uses the frame pointer
//  register for other purposes. For the x86, a function that uses EBP
//  as a frame pointer would begin with: push ebp; mov ebp,esp to save
//  the old value of EBP and give it a new value as a frame pointer. The
//  allocation of local variable space would have to come AFTER the move
//  instruction. A function that begins: push ebp; push esi; sub esp,24
//  is obviously not using EBP as a frame pointer. IDA is apparently
//  confused by the push ebp instruction being the first instruction
//  in the function. We will reset UseFP to false in this case.
// The inverse problem happens with a function that begins with instructions
//  other than push ebp; mov ebp,esp; ... etc. but eventually has those
//  instructions in the first basic block. For example, a C compiler generates
//  for the first block of main():
//    lea ecx,[esp+arg0]
//    and esp, 0xfffffff0
//    push dword ptr [ecx-4]
//    push ebp
//    mov ebp,esp
//    push ecx
//    sub esp,<framesize>
//
//  This function is obviously using EBP as a frame pointer, but IDA Pro marks
//  the function as not using a frame pointer. We will reset UseFP to true in
//  this case.
// NOTE: This logic should work for both Linux and Windows x86 prologues.
bool SMPFunction::MDFixUseFP(void) {
	list<SMPInstr>::iterator CurrInstr = this->Instrs.begin();
	ea_t addr = CurrInstr->GetAddr();

#if SMP_USE_SSA_FNOP_MARKER
	if (this->Instrs.begin() == CurrInstr)
		++CurrInstr;  // skip marker instruction
#endif

	if (!(this->UseFP)) {
		// See if we can detect the instruction "push ebp" followed by the instruction
		//  "mov ebp,esp" in the first basic block. The instructions do not have to be
		//  consecutive. If we find them, we will reset UseFP to true.
		bool FirstBlockProcessed = false;
		bool EBPSaved = false;
		bool ESPintoEBP = false;
		do {
			FirstBlockProcessed = CurrInstr->IsLastInBlock();
			if (!EBPSaved) { // still looking for "push ebp"
				if (CurrInstr->MDIsPushInstr() && CurrInstr->GetCmd().Operands[0].is_reg(R_bp)) {
					EBPSaved = true;
				}
			}
			else if (!ESPintoEBP) { // found "push ebp", looking for "mov ebp,esp"
				insn_t CurrCmd = CurrInstr->GetCmd();
				if ((CurrCmd.itype == NN_mov) 
					&& (CurrInstr->GetFirstDef()->GetOp().is_reg(R_bp))
					&& (CurrInstr->GetFirstUse()->GetOp().is_reg(R_sp))) {
					ESPintoEBP = true;
					FirstBlockProcessed = true; // exit loop
				}
			}
			++CurrInstr;
			addr = CurrInstr->GetAddr();
			// We must get EBP set to its frame pointer value before we reach the
			//  local frame allocation instruction (i.e. the subtraction of locals space
			//   from the stack pointer).
			FirstBlockProcessed |= (addr >= this->LocalVarsAllocInstr);
		} while (!FirstBlockProcessed);
		// If we found ESPintoEBP, we also found EBPSaved first, and we need to change
		//  this->UseFP to true and return true. Otherwise, return false.
		this->UseFP = ESPintoEBP;
		return ESPintoEBP;
	} // end if (!(this->UseFP))

	// At this point, this->UseFP must have been true on entry to this method and we will
	//  check whether it should be reset to false.
	while (addr < this->LocalVarsAllocInstr) {
		set<DefOrUse, LessDefUse>::iterator CurrDef = CurrInstr->GetFirstDef();
		while (CurrDef != CurrInstr->GetLastDef()) {
			if (CurrDef->GetOp().is_reg(R_bp))
				return false; // EBP got set before locals were allocated
		}
		++CurrInstr;
		addr = CurrInstr->GetAddr();
	}
	// If we found no defs of the frame pointer before the local vars
	//  allocation, then the frame pointer register is not being used
	//  as a frame pointer, just as a general callee-saved register.
	this->UseFP = false;
	msg("MDFixUseFP reset UseFP to false for %s\n", this->GetFuncName());
	return true;
} // end of SMPFunction::MDFixUseFP()

// Find the callee-saved reg offsets (negative offset from return address)
//  for all registers pushed onto the stack before the stack frame allocation
//  instruction.
void SMPFunction::MDFindSavedRegs(void) {
	list<SMPInstr>::iterator CurrInst;
	int RegIndex;
	func_t *CurrFunc = get_func(this->GetStartAddr());
	assert(NULL != CurrFunc);

	for (CurrInst = this->Instrs.begin(); CurrInst != this->Instrs.end(); ++CurrInst) {
		if (CurrInst->GetAddr() > this->LocalVarsAllocInstr)
			break;
		if (!(CurrInst->MDIsPushInstr()))
			continue;

		sval_t CurrOffset = get_spd(CurrFunc, CurrInst->GetAddr());
		if (CurrInst->GetCmd().itype == NN_push) {
			op_t PushedReg = CurrInst->GetPushedOpnd();
			if (o_reg == PushedReg.type) {
				RegIndex = (int) PushedReg.reg;
				if (RegIndex > R_di) {
					msg("WARNING: Skipping save of register %d\n", RegIndex);
					continue;
				}
				if (this->SavedRegLoc.at((size_t) RegIndex) == 0) {
					this->SavedRegLoc[(size_t) RegIndex] = CurrOffset - 4;
				}
				else {
					msg("WARNING: Multiple saves of register %d\n", RegIndex);
				}
			} // end if register push operand
		} // end if PUSH instruction
		else if (NN_pusha == CurrInst->GetCmd().itype) {
			// **!!** Handle pushes of all regs.
			this->SavedRegLoc[(size_t) R_ax] = CurrOffset - 4;
			this->SavedRegLoc[(size_t) R_cx] = CurrOffset - 8;
			this->SavedRegLoc[(size_t) R_dx] = CurrOffset - 12;
			this->SavedRegLoc[(size_t) R_bx] = CurrOffset - 16;
			this->SavedRegLoc[(size_t) R_sp] = CurrOffset - 20;
			this->SavedRegLoc[(size_t) R_bp] = CurrOffset - 24;
			this->SavedRegLoc[(size_t) R_si] = CurrOffset - 28;
			this->SavedRegLoc[(size_t) R_di] = CurrOffset - 32;
			break; // all regs accounted for
		}
		else if (CurrInst->MDIsEnterInstr()) {
			this->SavedRegLoc[(size_t) R_bp] = CurrOffset - 4;
		}
	} // end for all instructions

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

// Compute the ReturnRegTypes[] as the meet over all register types
//  at all return instructions.
void SMPFunction::MDFindReturnTypes(void) {
	list<SMPBasicBlock>::iterator CurrBlock;
	list<list<SMPInstr>::iterator>::iterator InstIter;
	vector<SMPOperandType> RegTypes;

	for (CurrBlock = this->Blocks.begin(); CurrBlock != this->Blocks.end(); ++CurrBlock) {
		if (CurrBlock->HasReturn()) {
			// Get the types of all registers at the RETURN point.
			//  Calculate the meet function over them.
			InstIter = CurrBlock->GetLastInstr();
			--InstIter;
			assert(RETURN == (*InstIter)->GetDataFlowType());
			set<DefOrUse, LessDefUse>::iterator CurrUse;
			for (CurrUse = (*InstIter)->GetFirstUse();
				CurrUse != (*InstIter)->GetLastUse();
				++CurrUse) {

				op_t UseOp = CurrUse->GetOp();
				if ((o_reg != UseOp.type) || (R_di < UseOp.reg))
					continue;
				this->ReturnRegTypes[UseOp.reg]
					= SMPTypeMeet(this->ReturnRegTypes.at(UseOp.reg),
						CurrUse->GetType());
			} // for all USEs in the RETURN instruction
		} // end if current block has a RETURN
	} // end for all blocks
	return;
} // end of SMPFunction::MDFindReturnTypes()

// Determine local variable boundaries in the stack frame.
void SMPFunction::BuildLocalVarTable(void) {
	// Currently we just use the info that IDA Pro has inferred from the direct
	//  addressing of stack locations.
	this->SemiNaiveLocalVarID();
	return;
} // end of SMPFunction::BuildLocalVarTable()

// Use the local variable offset list from IDA's stack frame structure to compute
//  the table of local variable boundaries.
void SMPFunction::SemiNaiveLocalVarID(void) {
	// NOTE: We use IDA Pro's offsets from this->FuncInfo (e.g. frsize) and NOT
	//  our own corrected values in our private data members. The offsets we
	//  read from the stack frame structure returned by get_frame() are consistent
	//  with other IDA Pro values, not with our corrected values.
	bool DebugFlag = false;
#if SMP_DEBUG_STACK_GRANULARITY
	DebugFlag |= (0 == strcmp("qSort3", this->GetFuncName()));
#endif
	func_t *FuncPtr = get_func(this->FuncInfo.startEA);
	if (NULL == FuncPtr) {
		msg("ERROR in SMPFunction::SemiNaiveLocalVarID; no func ptr\n");
	}
	assert(NULL != FuncPtr);
	struc_t *StackFrame = get_frame(FuncPtr);

	if (NULL == StackFrame) {
		msg("WARNING: No stack frame info from get_frame for %s\n", this->GetFuncName());
		return;
	}

	member_t *Member = StackFrame->members;
	for (size_t i = 0; i < StackFrame->memqty; ++i, ++Member) {
		long offset;
		char MemberName[MAXSMPVARSTR] = {'\0'};
		if (NULL == Member) {
			msg("NULL stack frame member pointer in %s\n", this->GetFuncName());
			break;
		}
		get_member_name(Member->id, MemberName, MAXSMPVARSTR - 1);
#if SMP_DEBUG_STACK_GRANULARITY
			msg("NULL stack frame member in %s\n", this->GetFuncName());
 		if (MemberName[0] == ' ') {
#if SMP_DEBUG_STACK_GRANULARITY
			msg("NULL stack frame name at offset %d in %s\n", offset, this->GetFuncName());
			msg("%s local var %s at offset %ld\n", this->GetFuncName(), MemberName, offset);
		}
		if (offset >= (long) this->LocalVarsSize)
			break;  // Stop after processing locals and outgoing args
#if 0
		// We want the offset from the stack pointer after local frame allocation.
		//  This subtraction would make it relative to the original stack pointer.
		offset -= this->FuncInfo.frsize;
#endif
		struct LocalVar TempLocal;
		TempLocal.offset = offset;
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		TempLocal.size = (size_t) -1; // compute later
		qstrncpy(TempLocal.VarName, MemberName, sizeof(TempLocal.VarName) - 1);
		this->LocalVarTable.push_back(TempLocal);
	} // end for all stack frame members
#if SMP_DEBUG_STACK_GRANULARITY
	msg("Computing %d local var sizes\n", this->LocalVarTable.size());
	// Now we want to fill in the size field for each local
	size_t VarLimit = this->LocalVarTable.size() - 1;
	assert(this->LocalVarTable.size() > 0);
	for (size_t VarIndex = 0; VarIndex < VarLimit; ++VarIndex) {
		this->LocalVarTable[VarIndex].size = this->LocalVarTable[VarIndex + 1].offset
			- this->LocalVarTable[VarIndex].offset;
	}
#if SMP_DEBUG_STACK_GRANULARITY
	msg("Computing last local var size for frsize %d\n", this->FuncInfo.frsize);
#endif
	// Size of last local is total frsize minus savedregs in frame minus offset of last local
	size_t SavedRegsSpace = 0; // portion of frsize that is saved regs, not locals.
	if (this->CalleeSavedRegsSize > this->FuncInfo.frregs) {
		// IDA Pro counts the save of EBP in frregs, but then EBP gets its new
		//  value and callee saved regs other than the old EBP push get counted
		//  in frsize rather than frregs. CalleeSavedRegsSize includes all saved
		//  regs on the stack, both above and below the current EBP offset.
		// NOTE: For windows, this has to be done differently, as callee saved regs
		//  happen at the bottom of the local frame, not the top.
		SavedRegsSpace = this->CalleeSavedRegsSize - this->FuncInfo.frregs;
		SavedRegsSpace = this->FuncInfo.frsize - this->LocalVarsSize;
	this->LocalVarTable.back().size = this->FuncInfo.frsize
		- SavedRegsSpace - this->LocalVarTable.back().offset;

	this->LocalVarOffsetLimit = this->LocalVarTable.back().offset 
		+ (adiff_t) this->LocalVarTable.back().size;

	// IDA Pro can have difficulty with some irregular functions such as are found
	//  in the C startup code. The frsize value might be bogus. Just punt on the
	//  local variable ID if that is the case.
	if (this->LocalVarOffsetLimit > (adiff_t) this->FuncInfo.frsize) {
		this->LocalVarTable.clear();
		msg("WARNING: Bad frsize for %s ; abandoning SemiNaiveLocalVarID.\n", this->FuncName);
		return;
	}
	assert(this->LocalVarOffsetLimit <= (adiff_t) this->FuncInfo.frsize);
	// Find out how many of the locals are really outgoing args.
	if (this->AnalyzedSP && !this->CallsAlloca && (BADADDR != this->LocalVarsAllocInstr)) {
		this->FindOutgoingArgsSize();
	}
	else {
		msg("FindOutgoingArgsSize not called for %s ", this->GetFuncName());
		msg("AnalyzedSP: %d CallsAlloca: %d LocalVarsAllocInstr: %x \n",
			this->AnalyzedSP, this->CallsAlloca, this->LocalVarsAllocInstr);
	}
	return;
} // end of SMPFunction::SemiNaiveLocalVarID()

// Determine how many bytes at the bottom of the stack frame (i.e. at bottom of
//  this->LocalVarsSize) are used for outgoing args. This is the case when the cdecl
//  calling convention is used, e.g. gcc/linux allocates local var space + out args space
//  in a single allocation and then writes outarg values directly to ESP+0, ESP+4, etc.
void SMPFunction::FindOutgoingArgsSize(void) {
	// Compute the lowest value reached by the stack pointer.
	list<SMPInstr>::iterator CurrInst;
	this->MinStackDelta = 20000; // Final value should be negative
	unsigned int BitWidthMask;
	bool DebugFlag = false;
#if SMP_DEBUG_STACK_GRANULARITY
	DebugFlag = (0 == strcmp("error_for_asm", this->GetFuncName()));
#endif
	if (DebugFlag) {
		msg("DEBUG: Entered FindOutgoingArgsSize for %s\n", this->GetFuncName());
#if SMP_IDAPRO52_WORKAROUND
		this->OutgoingArgsSize = 16;
		return;
	for (CurrInst = this->Instrs.begin(); CurrInst != this->Instrs.end(); ++CurrInst) {
#if SMP_USE_SSA_FNOP_MARKER
		if (this->Instrs.begin() == CurrInst)
			continue;  // skip marker instruction
#endif

		ea_t addr = CurrInst->GetAddr();
		sval_t sp_delta = get_spd(this->GetFuncInfo(), addr);
		if (sp_delta < this->MinStackDelta)
			this->MinStackDelta = sp_delta;
		if (addr == this->LocalVarsAllocInstr) {
			// Total stack pointer delta is sp_delta for the next instruction,
			//  because IDA updates the sp delta AFTER each instruction.
			list<SMPInstr>::iterator NextInst = CurrInst;
			++NextInst;
			sp_delta = get_spd(this->GetFuncInfo(), NextInst->GetAddr());
			this->AllocPointDelta = sp_delta;
		}
	}
#if SMP_DEBUG_STACK_GRANULARITY
	msg("AllocPointDelta: %d MinStackDelta: %d\n", this->AllocPointDelta, this->MinStackDelta);
#endif
	assert(0 > this->MinStackDelta);

	// Allocate a vector of stack frame entries, one for each byte of the stack frame.
	//  This will be our memory map for analyzing stack usage.
	int limit = 0;
#if 1
	if (this->LocalVarOffsetLimit > 0)
		limit = this->LocalVarOffsetLimit;
#endif
	for (int i = this->MinStackDelta; i < limit; ++i) {
		struct StackFrameEntry TempEntry;
		struct FineGrainedInfo TempFineGrained;
		TempEntry.VarPtr = NULL;
		TempEntry.offset = (long) i;
		TempEntry.Read = false;
		TempEntry.Written = false;
		TempEntry.AddressTaken = false;
		TempEntry.ESPRelativeAccess = false;
		TempEntry.EBPRelativeAccess = false;
		this->StackFrameMap.push_back(TempEntry);
		TempFineGrained.SignMiscInfo = 0;
		TempFineGrained.SizeInfo = 0;
		this->FineGrainedStackTable.push_back(TempFineGrained);
	}

	// Fill in the VarPtr fields for each StackFrameMap entry.
	if (0 <= this->AllocPointDelta) {
		msg("FATAL ERROR: AllocPointDelta = %d in %s\n", this->AllocPointDelta, this->GetFuncName());
	}
	assert(0 > this->AllocPointDelta);
	for (size_t i = 0; i < this->LocalVarTable.size(); ++i) {
		assert(this->LocalVarTable.at(i).offset >= 0);
		// Picture that AllocPointDelta is -200, MinStackDelta is -210, and
		//  the LocalVarTable[i].offset is +8 (i.e. 8 bytes above alloc point).
		//  Then base = 8 + (-200 - -210) = 8 + 10 = 18, the proper offset into
		//  the StackFrameMap.
		size_t base = (size_t) (this->LocalVarTable.at(i).offset
			+ (this->AllocPointDelta - this->MinStackDelta));
		size_t limit = base + this->LocalVarTable.at(i).size;
		if (limit > this->StackFrameMap.size()) {
			msg("ERROR: base = %d limit = %d StackFrameMap size = %d\n", base, limit,
				this->StackFrameMap.size());
		}
		assert(limit <= this->StackFrameMap.size());
		for (size_t MapIndex = base; MapIndex < limit; ++MapIndex) {
			this->StackFrameMap[MapIndex].VarPtr = &(this->LocalVarTable.at(i));
		}
	}

	// Iterate through all instructions and record stack frame accesses in the StackFrameMap.
	for (CurrInst = this->Instrs.begin(); CurrInst != this->Instrs.end(); ++CurrInst) {
#if SMP_USE_SSA_FNOP_MARKER
		if (this->Instrs.begin() == CurrInst)
			continue;  // skip marker instruction
#endif

		sval_t sp_delta = get_spd(this->GetFuncInfo(), CurrInst->GetAddr());
		if (0 < sp_delta) {
			// Stack underflow; about to assert
			msg("Stack underflow at %x %s sp_delta: %d\n", CurrInst->GetAddr(),
				CurrInst->GetDisasm(), sp_delta);
		}
		assert(0 >= sp_delta);
		ea_t offset;
		size_t DataSize;
		bool UsedFramePointer;
		bool SignedMove;
		bool UnsignedMove;
		if (CurrInst->HasDestMemoryOperand()) {
			set<DefOrUse, LessDefUse>::iterator CurrDef;
			for (CurrDef = CurrInst->GetFirstDef(); CurrDef != CurrInst->GetLastDef(); ++CurrDef) {
				op_t TempOp = CurrDef->GetOp();
				if (TempOp.type != o_phrase && TempOp.type != o_displ)
					continue;
				if (this->MDGetStackOffsetAndSize(CurrInst, TempOp, sp_delta, offset, DataSize, UsedFramePointer,
					SignedMove, UnsignedMove)) {
					assert(0 <= offset);
					if (offset >= this->FuncInfo.frsize)
						continue;  // limit processing to outgoing args and locals
					if ((offset + DataSize) > this->StackFrameMap.size()) {
						msg("ERROR: offset = %d DataSize = %d FrameMapSize = %d\n",
							offset, DataSize, this->StackFrameMap.size());
					}
					assert((offset + DataSize) <= this->StackFrameMap.size());
					for (int j = 0; j < (int) DataSize; ++j) {
						this->StackFrameMap[offset + j].Written = true;
							this->StackFrameMap[offset + j].ESPRelativeAccess = true;
							this->StackFrameMap[offset + j].EBPRelativeAccess = true;
					BitWidthMask = ComputeOperandBitWidthMask(TempOp, DataSize);
					this->FineGrainedStackTable.at(offset).SizeInfo |= BitWidthMask;
					this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_WRITTEN;
					if (!UsedFramePointer) {
						this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_SP_RELATIVE;
					}
					else {
						this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_FP_RELATIVE;
					}
					// We will process the signedness of stores later, so that loads can take precedence
					//  over stores in determining signedness.
				} // end if MDGetStackOffsetAndSize()
			} // end for all DEFs
		} // end if DestMemoryOperand

		if (CurrInst->HasSourceMemoryOperand()) {
			set<DefOrUse, LessDefUse>::iterator CurrUse;
			for (CurrUse = CurrInst->GetFirstUse(); CurrUse != CurrInst->GetLastUse(); ++CurrUse) {
				op_t TempOp = CurrUse->GetOp();
				if (TempOp.type != o_phrase && TempOp.type != o_displ)
					continue;
				if (this->MDGetStackOffsetAndSize(CurrInst, TempOp, sp_delta, offset, DataSize, UsedFramePointer,
					SignedMove, UnsignedMove)) {
					assert(0 <= offset);
					if (offset >= this->FuncInfo.frsize)
						continue;  // limit processing to outgoing args and locals
					if ((offset + DataSize) > this->StackFrameMap.size()) {
						msg("ERROR: offset = %d DataSize = %d FrameMapSize = %d\n",
							offset, DataSize, this->StackFrameMap.size());
					}
					assert((offset + DataSize) <= this->StackFrameMap.size());
					for (int j = 0; j < (int) DataSize; ++j) {
						this->StackFrameMap[offset + j].Read = true;
						if (!UsedFramePointer)
							this->StackFrameMap[offset + j].ESPRelativeAccess = true;
						else
							this->StackFrameMap[offset + j].EBPRelativeAccess = true;
					}
					BitWidthMask = ComputeOperandBitWidthMask(TempOp, DataSize);
					this->FineGrainedStackTable.at(offset).SizeInfo |= BitWidthMask;
					this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_READ;
					if (!UsedFramePointer) {
						this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_SP_RELATIVE;
					}
					else {
						this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_FP_RELATIVE;
					}
					if (SignedMove) {
						this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_SIGNED;
					}
					else if (UnsignedMove) {
						this->FineGrainedStackTable.at(offset).SignMiscInfo |= FG_MASK_UNSIGNED;
					}
				} // end if MDGetStackOffsetAndSize()
			} // end for all USEs
		} // end if SourceMemoryOperand
		// NOTE: Detect taking the address of stack locations. **!!**
	} // end for all instructions

	// If function is a leaf function, set OutgoingArgsSize to zero and return.
	if (this->IsLeaf()) {
		this->OutgoingArgsSize = 0;
		return;
	}

	// For non-leaf functions, set the OutgoingArgsSize to the write-only, ESP-relative
	//  region of the bottom of the StackFrameMap.
	for (size_t MapIndex = 0; MapIndex < this->StackFrameMap.size(); ++MapIndex) {
		// Some of the bottom of the stack frame might be below the local frame allocation.
		//  These are pushes that happened after allocation, etc. We skip over these
		//  locations and define the outgoing args region to start strictly at the bottom
		//  of the local frame allocation.
		struct StackFrameEntry TempEntry = this->StackFrameMap.at(MapIndex);
		if (DebugFlag) {
			msg("StackFrameMap entry %d: offset: %ld Read: %d Written: %d ESP: %d EBP: %d\n",
				MapIndex, TempEntry.offset, TempEntry.Read, TempEntry.Written,
				TempEntry.ESPRelativeAccess, TempEntry.EBPRelativeAccess);
		}
		if (TempEntry.offset < this->AllocPointDelta)
			continue;
		if (TempEntry.Read || TempEntry.EBPRelativeAccess || !TempEntry.Written
			|| !TempEntry.ESPRelativeAccess)
			break;
		this->OutgoingArgsSize++;
	}
	// Sometimes we encounter unused stack space above the outgoing args. Lump this space
	//  in with the outgoing args. We detect this by noting when the outgoing args space
	//  has only partially used the space assigned to a local var.
	if ((0 < this->OutgoingArgsSize) && (this->OutgoingArgsSize < this->FuncInfo.frsize)) {
		long MapIndex = (this->AllocPointDelta - this->MinStackDelta);
		assert(0 <= MapIndex);
		MapIndex += (((long) this->OutgoingArgsSize) - 1);
		struct StackFrameEntry TempEntry = this->StackFrameMap.at((size_t) MapIndex);
		if (NULL == TempEntry.VarPtr) { // Gap in stack frame; IDA 6.0
			msg("Gap in stack frame: %s\n", this->FuncName);
		}
		else if (this->OutgoingArgsSize < (TempEntry.VarPtr->offset + TempEntry.VarPtr->size)) {
			msg("OutGoingArgsSize = %d", this->OutgoingArgsSize);
			this->OutgoingArgsSize = TempEntry.VarPtr->offset + TempEntry.VarPtr->size;
			msg(" adjusted to %d\n", this->OutgoingArgsSize);
		}
	}
	return;
} // end of SMPFunction::FindOutgoingArgsSize()

// If TempOp reads or writes to a stack location, return the offset (relative to the initial
//  stack pointer value) and the size in bytes of the data access. Also return whether the
//  access was frame-pointer-relative, and whether signedness can be inferred due to a load
//  from the stack being zero-extended or sign-extended.
// NOTE: TempOp must be of type o_displ or o_phrase, as no other operand type could be a
//  stack memory access.
// sp_delta is the stack pointer delta of the current instruction, relative to the initial
//  stack pointer value for the function.
// Return true if a stack memory access was found in TempOp, false otherwise.
bool SMPFunction::MDGetStackOffsetAndSize(list<SMPInstr>::iterator Instr, op_t TempOp, sval_t sp_delta, ea_t &offset, size_t &DataSize, bool &FP,
										  bool &Signed, bool &Unsigned) {
	assert((o_displ == TempOp.type) || (o_phrase == TempOp.type));
	MDExtractAddressFields(TempOp, BaseReg, IndexReg, ScaleFactor, offset);
	if (TempOp.type == o_phrase) {
		assert(offset == 0);  // implicit zero, as in [esp] ==> [esp+0]
	}
	if ((BaseReg == R_sp) || (IndexReg == R_sp)) {
		// ESP-relative constant offset
		offset += sp_delta; // base offsets from entry ESP value
		offset -= this->MinStackDelta; // convert to StackFrameMap index
		// Get size of data written
		DataSize = GetOpDataSize(TempOp);
		FP = false;
		unsigned short opcode = Instr->GetCmd().itype;
		Unsigned = (opcode == NN_movzx);
		Signed = (opcode == NN_movsx);
		return true;
	}
	else if (this->UseFP && ((BaseReg == R_bp) || (IndexReg == R_bp))) {
		offset -= this->FuncInfo.frregs; // base offsets from entry ESP value
		offset -= this->MinStackDelta; // convert to StackFrameMap index
		DataSize = GetOpDataSize(TempOp);
		FP = true;
		unsigned short opcode = Instr->GetCmd().itype;
		Unsigned = (opcode == NN_movzx);
		Signed = (opcode == NN_movsx);
		return true;
	}
	else {
		return false;
	}
} // end of SMPFunction::MDGetStackOffsetAndSize()
		
// Return fine grained stack entry for stack op TempOp from instruction at InstAddr
bool SMPFunction::MDGetFGStackLocInfo(ea_t InstAddr, op_t TempOp, struct FineGrainedInfo &FGEntry) {
	int BaseReg;
	int IndexReg;
	ushort ScaleFactor;
	ea_t offset;
	int SignedOffset;

	assert((o_displ == TempOp.type) || (o_phrase == TempOp.type));
	MDExtractAddressFields(TempOp, BaseReg, IndexReg, ScaleFactor, offset);
	sval_t sp_delta = get_spd(this->GetFuncInfo(), InstAddr);

	SignedOffset = (int) offset;

	if (TempOp.type == o_phrase) {
		assert(offset == 0);  // implicit zero, as in [esp] ==> [esp+0]
	}
	if ((BaseReg == R_sp) || (IndexReg == R_sp)) {
		// ESP-relative constant offset
		offset += sp_delta; // base offsets from entry ESP value
		offset -= this->MinStackDelta; // convert to StackFrameMap index
	}
	else if (this->UseFP && ((BaseReg == R_bp) || (IndexReg == R_bp))) {
		offset -= this->FuncInfo.frregs; // base offsets from entry ESP value
		offset -= this->MinStackDelta; // convert to StackFrameMap index
	}
	else {
		return false;
	}
	// We did not return false, so we should have a good offset. Use it to
	//  pass back the fine grained stack table entry for that offset.
	if ((0 > offset) || (offset >= this->FineGrainedStackTable.size())) {
		msg("ERROR: FG stack table index out of range in MDGetFGStackLocInfo at %x\n", InstAddr);
		FGEntry.SignMiscInfo = 0;
		FGEntry.SizeInfo = 0;
	}
	else {
		FGEntry = this->FineGrainedStackTable.at(offset);
	}
	return true;
} // end of SMPFunction::MDGetFGStackLocInfo()

// retrieve DEF addr from GlobalDefAddrBySSA or return BADADDR
ea_t SMPFunction::GetGlobalDefAddr(op_t DefOp, int SSANum) {
	map<int, ea_t>::iterator DefAddrMapIter;
	map<int, ea_t>::iterator MapResult;
	ea_t DefAddr = BADADDR; // BADADDR means we did not find it

	int HashedName = HashGlobalNameAndSSA(DefOp, SSANum);
	MapResult = this->GlobalDefAddrBySSA.find(HashedName);
	if (MapResult != this->GlobalDefAddrBySSA.end()) { // Found it.
		DefAddr = (ea_t) MapResult->second;
	}
	return DefAddr;
} // end of SMPFunction::GetGlobalDefAddr()

// Retrieve block iterator for InstAddr from InstBlockMap; assert if failure
list<SMPBasicBlock>::iterator SMPFunction::GetBlockFromInstAddr(ea_t InstAddr) {
	map<ea_t, list<SMPBasicBlock>::iterator>::iterator MapEntry;
	MapEntry = this->InstBlockMap.find(InstAddr);
	assert(MapEntry != this->InstBlockMap.end());
	return MapEntry->second;
}

// Given block # and PhiDef op_t and SSANum, return the Phi iterator or assert.
set<SMPPhiFunction, LessPhi>::iterator SMPFunction::GetPhiIterForPhiDef(size_t BlockNumber, op_t DefOp, int SSANum) {
	list<SMPBasicBlock>::iterator DefBlock = this->RPOBlocks.at(BlockNumber);
	set<SMPPhiFunction, LessPhi>::iterator PhiIter = DefBlock->FindPhi(DefOp);
	assert(PhiIter != DefBlock->GetLastPhi());
	return PhiIter;
}
// Is DestOp within the outgoing args area? Assume it must be an ESP-relative
//  DEF operand in order to be a write to the outgoing args area.
bool SMPFunction::WritesToOutgoingArgs(op_t DestOp) {
	bool OutArgWrite = false;
	int BaseReg, IndexReg;
	ushort ScaleFactor;
	ea_t offset;

	if (this->IsLeaf())
		return false;

	MDExtractAddressFields(DestOp, BaseReg, IndexReg, ScaleFactor, offset);
	if ((BaseReg != R_sp) && (IndexReg != R_sp))
		return false;
	if (((BaseReg == R_sp) && (IndexReg != R_none))
		|| ((IndexReg == R_sp) && (BaseReg != R_none))
		|| (0 < ScaleFactor)) {

		msg("WARNING: WritesToOutgoingArgs called with indexed write.");
		PrintOperand(DestOp);
		return false;
	}

	if (!this->OutgoingArgsComputed) {
		OutArgWrite = true; // be conservative
	}
	else {
		OutArgWrite = (offset < this->OutgoingArgsSize);
	}
	return OutArgWrite;
} // end of SMPFunction::WritesToOutgoingArgs()

// Is DestOp a direct memory access above the local vars frame?
bool SMPFunction::WritesAboveLocalFrame(op_t DestOp) {
	bool InArgWrite = false;
	int BaseReg, IndexReg;
	ushort ScaleFactor;
	ea_t offset;
	long SignedOffset;

	MDExtractAddressFields(DestOp, BaseReg, IndexReg, ScaleFactor, offset);
	SignedOffset = (long) offset;
	bool ESPrelative = (BaseReg == R_sp) || (IndexReg == R_sp);
	bool EBPrelative = this->UseFP && ((BaseReg == R_bp) || (IndexReg == R_bp));
	if (!(ESPrelative || EBPrelative))
		return false;
	if (((IndexReg != R_none) && (BaseReg != R_none))
		|| (0 < ScaleFactor)) {

		msg("WARNING: WritesAboveLocalFrame called with indexed write.");
	InArgWrite = (ESPrelative && (SignedOffset > ((long) this->LocalVarsSize)))
		|| (EBPrelative && (SignedOffset > 0));
}// end of SMPFunction::WritesAboveLocalFrame()

// Is DestOp an indexed write above the local vars frame?
bool SMPFunction::IndexedWritesAboveLocalFrame(op_t DestOp) 
{
	bool InArgWrite = false;
	int BaseReg, IndexReg;
	ushort ScaleFactor;
	ea_t offset;

	MDExtractAddressFields(DestOp, BaseReg, IndexReg, ScaleFactor, offset);
	bool ESPrelative = (BaseReg == R_sp) || (IndexReg == R_sp);
	bool EBPrelative = this->UseFP && ((BaseReg == R_bp) || (IndexReg == R_bp));
	if (!(ESPrelative || EBPrelative))
		return false;

	InArgWrite = (ESPrelative && (offset > this->LocalVarsSize))
		|| (EBPrelative && (offset > 0));

	return InArgWrite;
}	 // end of SMPFunction::IndexedWritesAboveLocalFrame
// Find evidence of calls to alloca(), which appear as stack space allocations (i.e.
//  subtractions from the stack pointer) AFTER the local frame allocation instruction
//  for this function.
// Return true if such an allocation is found and false otherwise.
bool SMPFunction::FindAlloca(void) {
	list<SMPInstr>::iterator CurrInst;
	for (CurrInst = this->Instrs.begin(); CurrInst != this->Instrs.end(); ++CurrInst) {
#if SMP_USE_SSA_FNOP_MARKER
		if (this->Instrs.begin() == CurrInst)
			continue;  // skip marker instruction
#endif

		if ((CurrInst->GetAddr() > this->LocalVarsAllocInstr) && CurrInst->MDIsFrameAllocInstr()) {
			return true;
		}
	}
	return false;
} // end of SMPFunction::FindAlloca()

// Emit the annotations describing the regions of the stack frame.
void SMPFunction::EmitStackFrameAnnotations(FILE *AnnotFile, list<SMPInstr>::iterator Instr) {
	ea_t addr = Instr->GetAddr();

#if 0
	if (0 < IncomingArgsSize) {
		qfprintf(AnnotFile, "%10x %6d INARGS STACK esp + %d %s \n",
				addr, IncomingArgsSize,
				(LocalVarsSize + CalleeSavedRegsSize + RetAddrSize),
				Instr->GetDisasm());
		qfprintf(AnnotFile, "%10x %6d MEMORYHOLE STACK esp + %d ReturnAddress \n",
				addr, RetAddrSize, (LocalVarsSize + CalleeSavedRegsSize));
	}
	if (0 < CalleeSavedRegsSize) {
		qfprintf(AnnotFile, "%10x %6d MEMORYHOLE STACK esp + %d CalleeSavedRegs \n",
				addr, CalleeSavedRegsSize, LocalVarsSize);
		unsigned long ParentReferentID = DataReferentID++;
		qfprintf(AnnotFile, "%10x %6d DATAREF STACK %ld esp + %d PARENT LocalFrame LOCALFRAME\n",
				addr, LocalVarsSize, ParentReferentID, 0);
#if SMP_COMPUTE_STACK_GRANULARITY
		if (this->AnalyzedSP && !this->CallsAlloca && (BADADDR != this->LocalVarsAllocInstr)) {
			// We can only fine-grain the stack frame if we were able to analyze the stack
			if (this->OutgoingArgsSize > 0) {
				qfprintf(AnnotFile, "%10x %6d DATAREF STACK %ld esp + %d CHILDOF %ld OFFSET %d OutArgsRegion OUTARGS\n",
					addr, this->OutgoingArgsSize, DataReferentID, 0, ParentReferentID, 0);
				++DataReferentID;
#if SMP_DEBUG_STACK_GRANULARITY
			msg("LocalVarTable of size %d for function %s\n", this->LocalVarTable.size(),
				this->GetFuncName());
			for (size_t i = 0; i < this->LocalVarTable.size(); ++i) {
#if SMP_DEBUG_STACK_GRANULARITY
				msg("Entry %d offset %d size %d name %s\n", i, this->LocalVarTable[i].offset,
					this->LocalVarTable[i].size, this->LocalVarTable[i].VarName);
				// Don't emit annotations for incoming or outgoing args or anything else
				//  above or below the current local frame.
				if ((this->LocalVarTable[i].offset >= (long) this->FuncInfo.frsize)
					|| (this->LocalVarTable[i].offset < (long) this->OutgoingArgsSize))
					continue;
				qfprintf(AnnotFile, "%10x %6d DATAREF STACK %ld esp + %ld CHILDOF %ld OFFSET %ld LOCALVAR %s \n",
					addr, this->LocalVarTable[i].size, DataReferentID,
					this->LocalVarTable[i].offset, ParentReferentID,
					this->LocalVarTable[i].offset, this->LocalVarTable[i].VarName);
				++DataReferentID;
		} // end if (this->AnalyzedSP and not Alloca .... )
	} // end if (0 < LocalVarsSize)
	return;
} // end of SMPFunction::EmitStackFrameAnnotations() 

// Main data flow analysis driver. Goes through the function and
//  fills all objects for instructions, basic blocks, and the function
//  itself.
void SMPFunction::Analyze(void) {
	list<SMPInstr>::iterator FirstInBlock = this->Instrs.end();
	   // For starting a basic block
	list<SMPInstr>::iterator LastInBlock = this->Instrs.end();
	   // Terminating a basic block

#if SMP_DEBUG_CONTROLFLOW
	msg("Entering SMPFunction::Analyze.\n");
#endif

	// Get some basic info from the FuncInfo structure.
	this->Size = this->FuncInfo.endEA - this->FuncInfo.startEA;
	this->UseFP = (0 != (this->FuncInfo.flags & (FUNC_FRAME | FUNC_BOTTOMBP)));
	this->StaticFunc = (0 != (this->FuncInfo.flags & FUNC_STATIC));
	this->LibFunc = (0 != (this->FuncInfo.flags & FUNC_LIB));
	get_func_name(this->FuncInfo.startEA, this->FuncName,
		sizeof(this->FuncName) - 1);
	this->BlockCount = 0;
	this->AnalyzedSP = this->FuncInfo.analyzed_sp();

#if SMP_DEBUG_CONTROLFLOW
	msg("SMPFunction::Analyze: got basic info.\n");
#endif

	// Cycle through all chunks that belong to the function.
	func_tail_iterator_t FuncTail(this->GetFuncInfo());
	size_t ChunkCounter = 0;
	for (bool ChunkOK = FuncTail.main(); ChunkOK; ChunkOK = FuncTail.next()) {
		const area_t &CurrChunk = FuncTail.chunk();
		++ChunkCounter;
		if (1 < ChunkCounter) {
			this->SharedChunks = true;
#if SMP_DEBUG_CHUNKS
			msg("Found tail chunk for %s at %x\n", this->FuncName, CurrChunk.startEA);
#endif
		}
		// Build the instruction and block lists for the function.
		for (ea_t addr = CurrChunk.startEA; addr < CurrChunk.endEA;
			addr = get_item_end(addr)) {
			flags_t InstrFlags = getFlags(addr);
			if (isHead(InstrFlags) && isCode(InstrFlags)) {
				SMPInstr CurrInst = SMPInstr(addr);
				// Fill in the instruction data members.
#if SMP_DEBUG_CONTROLFLOW
				msg("SMPFunction::Analyze: calling CurrInst::Analyze.\n");
#endif
				CurrInst.Analyze();
				if (SMPBinaryDebug) {
					msg("Disasm:  %s \n", CurrInst.GetDisasm());
				}
#if SMP_USE_SSA_FNOP_MARKER
				if (this->Instrs.empty()) {
					// First instruction in function. We want to create a pseudo-instruction
					//  at the top of the function that can hold SSA DEFs for LiveIn names
					//  to the function. We use a floating point no-op as the pseudo-inst.
					//  The code address is one less than the start address of the function.
					SMPInstr MarkerInst = SMPInstr(addr - 1);
					MarkerInst.AnalyzeMarker();
					assert(FirstInBlock == this->Instrs.end());
					this->Instrs.push_back(MarkerInst);
				}
#endif
				if (this->AnalyzedSP) {
					// Audit the IDA SP analysis.
					sval_t sp_delta = get_spd(this->GetFuncInfo(), addr);
					// sp_delta is difference between current value of stack pointer
					//  and value of the stack pointer coming into the function. It
					//  is updated AFTER each instruction. Thus, it should not get back
					//  above zero (e.g. to +4) until after a return instruction.
					if (sp_delta > 0) {
						// Stack pointer has underflowed, according to IDA's analysis,
						//  which is probably incorrect.
						this->AnalyzedSP = false;
						msg("Resetting AnalyzedSP to false for %s\n", this->GetFuncName());
						msg("Underflowing instruction: %s sp_delta: %d\n", CurrInst.GetDisasm(),
							sp_delta);
					}
					else if (sp_delta == 0) {
						// Search for tail calls.
						if (CurrInst.IsBranchToFarChunk()) {
							// After the stack has been restored to the point at which
							//  we are ready to return, we instead find a jump to a
							//  far chunk. This is the classic tail call optimization:
							//  the return statement has been replaced with a jump to
							//  another function, which will return not to this function,
							//  but to the caller of this function.
							CurrInst.SetTailCall();
							msg("Found tail call at %x from %s: %s\n", addr, this->GetFuncName(),
								CurrInst.GetDisasm());
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							// Just like a return instruction, we must make
							//  DEF-USE chains reach the tail call.
							CurrInst.MDAddRegUse(R_ax, false);
							CurrInst.MDAddRegUse(R_bx, false);
							CurrInst.MDAddRegUse(R_cx, false);
							CurrInst.MDAddRegUse(R_dx, false);
							CurrInst.MDAddRegUse(R_bp, false);
							CurrInst.MDAddRegUse(R_si, false);
							CurrInst.MDAddRegUse(R_di, false);
				// Find all functions that call the current function.
				xrefblk_t CurrXrefs;
				if (!FoundAllCallers) {
					for (bool ok = CurrXrefs.first_to(CurrInst.GetAddr(), XREF_ALL);
						ok;
						ok = CurrXrefs.next_to()) {
						if ((CurrXrefs.from != 0) && (CurrXrefs.iscode)) {
							// Make sure it is not a fall-through. Must be a
							//  control-flow instruction of some sort, including
							//  direct or indirect calls or tail calls.
							SMPInstr CallInst(CurrXrefs.from);
							CallInst.Analyze();
							SMPitype CallType = CallInst.GetDataFlowType();
							if ((COND_BRANCH <= CallType) && (RETURN >= CallType)) {
								// Found a caller, with its call address in CurrXrefs.from
								this->AddCallSource(CurrXrefs.from);
							}
						}
					}
					FoundAllCallers = true; // only do this for first inst
				}

				SMPitype DataFlowType = CurrInst.GetDataFlowType();
				if ((DataFlowType == INDIR_CALL)|| (DataFlowType == CALL)) {
					// See if IDA has determined the target of the call.
					ea_t TargetAddr = CurrInst.GetCallTarget();
					bool LinkedToTarget = (BADADDR != TargetAddr);
					if (LinkedToTarget) {
						if (0 == TargetAddr) {
							msg("WARNING: Ignoring NULL call target (unreachable) at %x\n", CurrInst.GetAddr());
							this->AllCallTargets.push_back(TargetAddr);
							if (INDIR_CALL == DataFlowType) {
								this->IndirectCallTargets.push_back(TargetAddr);
							}
							else {
								this->DirectCallTargets.push_back(TargetAddr);
							}
					if (DataFlowType == INDIR_CALL) {
						this->IndirectCalls = true;
						this->UnresolvedIndirectCalls = (!LinkedToTarget);
					}
				} // end if INDIR_CALL or CALL
				else if (DataFlowType == INDIR_JUMP)
					this->IndirectJumps = true;

				// Before we insert the instruction into the instruction
				//  list, determine if it is a jump target that does not
				//  follow a basic block terminator. This is the special case
				//  of a CASE in a SWITCH that falls through into another
				//  CASE, for example. The first sequence of statements
				//  was not terminated by a C "break;" statement, so it
				//  looks like straight line code, but there is an entry
				//  point at the beginning of the second CASE sequence and
				//  we have to split basic blocks at the entry point.
				if ((FirstInBlock != this->Instrs.end())
					&& CurrInst.IsJumpTarget()) {
#if SMP_DEBUG_CONTROLFLOW
					msg("SMPFunction::Analyze: hit special jump target case.\n");
#endif
					LastInBlock = --(this->Instrs.end());
					SMPBasicBlock CurrBlock = SMPBasicBlock(this, FirstInBlock,
						LastInBlock);
					CurrBlock.Analyze();
					// If not the first chunk in the function, it is a shared
					//  tail chunk.
					if (ChunkCounter > 1) {
						CurrBlock.SetShared();
					}
					FirstInBlock = this->Instrs.end();
					LastInBlock = this->Instrs.end();
					this->Blocks.push_back(CurrBlock);
					this->BlockCount += 1;
				}

#if SMP_DEBUG_CONTROLFLOW
		msg("SMPFunction::Analyze: putting CurrInst on list.\n");
#endif
				// Insert instruction at end of list.
				this->Instrs.push_back(CurrInst);

				// Find basic block leaders and terminators.
				if (FirstInBlock == this->Instrs.end()) {
#if SMP_DEBUG_CONTROLFLOW
					msg("SMPFunction::Analyze: setting FirstInBlock.\n");
#if SMP_USE_SSA_FNOP_MARKER
					if (2 == this->Instrs.size()) {
						// Just pushed first real instruction, after the fnop marker.
						FirstInBlock = this->Instrs.begin();
					}
					else {
						FirstInBlock = --(this->Instrs.end());
					}
#else
					FirstInBlock = --(this->Instrs.end());
				}
				if (CurrInst.IsBasicBlockTerminator()) {
#if SMP_DEBUG_CONTROLFLOW
		msg("SMPFunction::Analyze: found block terminator.\n");
#endif
					LastInBlock = --(this->Instrs.end());
					SMPBasicBlock CurrBlock = SMPBasicBlock(this, FirstInBlock, LastInBlock);
					CurrBlock.Analyze();
					// If not the first chunk in the function, it is a shared
					//  tail chunk.
					if (ChunkCounter > 1) {
						CurrBlock.SetShared();
					}
					FirstInBlock = this->Instrs.end();
					LastInBlock = this->Instrs.end();
					this->Blocks.push_back(CurrBlock);
					this->BlockCount += 1;

					// Is the instruction a branch to a target outside the function? If
					//  so, this function has shared tail chunks.
					if (CurrInst.IsBranchToFarChunk() && (!CurrInst.IsTailCall())) {
						this->SharedChunks = true;
					}
				}
			} // end if (isHead(InstrFlags) && isCode(InstrFlags)
		} // end for (ea_t addr = CurrChunk.startEA; ... )

		// Handle the special case in which a function does not terminate
		//  with a return instruction or any other basic block terminator.
		//  Sometimes IDA Pro sees a call to a NORET function and decides
		//  to not include the dead code after it in the function. That
		//  dead code includes the return instruction, so the function no
		//  longer includes a return instruction and terminates with a CALL.
		if (FirstInBlock != this->Instrs.end()) {
			LastInBlock = --(this->Instrs.end());
			SMPBasicBlock CurrBlock = SMPBasicBlock(this, FirstInBlock, LastInBlock);
			CurrBlock.Analyze();
			// If not the first chunk in the function, it is a shared
			//  tail chunk.
			if (ChunkCounter > 1) {
				CurrBlock.SetShared();
			}
			FirstInBlock = this->Instrs.end();
			LastInBlock = this->Instrs.end();
			this->Blocks.push_back(CurrBlock);
			this->BlockCount += 1;
		}
	} // end for (bool ChunkOK = ...)

	// Now that we have all instructions and basic blocks, link each instruction
	//  to its basic block. Note that the instruction has to be linked to the copy
	//  of the basic block in this->Blocks(), not to the original SMPBasicBlock
	//  object that was constructed and destructed on the stack above. (Ouch!
	//  Very painful memory corruption debugging lesson.)
	list<SMPBasicBlock>::iterator CurrBlock;
	list<list<SMPInstr>::iterator>::iterator InstIter;
	for (CurrBlock = this->Blocks.begin(); CurrBlock != this->Blocks.end(); ++CurrBlock) {
		for (InstIter = CurrBlock->GetFirstInstr(); InstIter != CurrBlock->GetLastInstr(); ++InstIter) {
			(*InstIter)->SetBlock(CurrBlock->GetThisBlock());
		}
	}

#if KLUDGE_VFPRINTF_FAMILY
	if (0 != strstr(this->GetFuncName(), "printf")) {
		this->SharedChunks = true;
		msg("Kludging function %s\n", this->GetFuncName());
	}
#endif

#if SMP_IDAPRO52_WORKAROUND
	if (0 == strcmp(this->GetFuncName(), "error_for_asm")) {
		this->SharedChunks = true;
		msg("Kludging function %s\n", this->GetFuncName());
	}
#endif

	// Set up basic block links and map of instructions to blocks.
	if (!(this->HasSharedChunks())) {
		this->SetLinks();
		this->RPONumberBlocks();

		// Figure out the stack frame and related info.
		this->SetStackFrameInfo();

		list<SMPInstr>::iterator CurrInst;
		bool GoodRTL;
		this->BuiltRTLs = true;
		for (CurrInst = this->Instrs.begin(); CurrInst != this->Instrs.end(); ++CurrInst) {
			// Build tree RTLs for the instruction.
			GoodRTL = CurrInst->BuildRTL();
			this->BuiltRTLs = (this->BuiltRTLs && GoodRTL);
#if SMP_DEBUG_BUILD_RTL
			if (!GoodRTL) {
				msg("ERROR: Cannot build RTL at %x for %s\n", CurrInst->GetAddr(), 
					CurrInst->GetDisasm());
			}
			// Detect indirect memory references.
			CurrInst->AnalyzeIndirectRefs(this->UseFP);
	else { // has shared chunks; still want to compute stack frame info
#if SMP_DEBUG_CONTROLFLOW
		msg("SMPFunction::Analyze: set stack frame info.\n");
#ifdef SMP_DEBUG_FUNC
		msg(" %s has shared chunks \n", this->GetFuncName());
#endif
		// Figure out the stack frame and related info.
		this->SetStackFrameInfo();
	}
	// We can finally search for stack loads now that UseFP has been fixed by
	//  GetStackFrameInfo(). Otherwise, we would do this in SMPInstr::Analyze(),
	//  but the UseFP flag is not ready that early.
	list<SMPInstr>::iterator StLoadInstIter = this->Instrs.begin();
	while (StLoadInstIter != this->Instrs.end()) {
		StLoadInstIter->MDFindLoadFromStack(this->UseFP);
		++StLoadInstIter;
	}

	// Audit the call instructions and call targets.
	if ((!this->AllCallTargets.empty()) || this->UnresolvedIndirectCalls) {
		bool FoundBadCallTarget = false;
		vector<ea_t>::iterator CurrTarget = this->AllCallTargets.begin();
		while (CurrTarget != this->AllCallTargets.end()) {
			if ((this->FirstEA <= *CurrTarget) && (this->FuncInfo.endEA >= *CurrTarget)) {
				// Found a call target that is within the function.
				FoundBadCallTarget = true;
				if (this->FirstEA == *CurrTarget) { // Direct recursion, not a pseudo-jump
					this->DirectlyRecursive = true;
				}
				CurrTarget = this->AllCallTargets.erase(CurrTarget);
			}
			else {
				++CurrTarget;
			}
		}
		if (FoundBadCallTarget) {
			// We have to mark the pseudo-call instructions and audit the direct and
			//  indirect call target vectors.

			// Audit direct call targets.
			CurrTarget = this->DirectCallTargets.begin();
			while (CurrTarget != this->DirectCallTargets.end()) {
				if ((this->FirstEA <= *CurrTarget) && (this->FuncInfo.endEA >= *CurrTarget)) {
					// Found a call target that is within the function.
					CurrTarget = this->DirectCallTargets.erase(CurrTarget);
				}
				else {
					++CurrTarget;
				}
			}
			// Audit indirect call targets.
			CurrTarget = this->IndirectCallTargets.begin();
			while (CurrTarget != this->IndirectCallTargets.end()) {
				if ((this->FirstEA <= *CurrTarget) && (this->FuncInfo.endEA >= *CurrTarget)) {
					// Found a call target that is within the function.
					CurrTarget = this->IndirectCallTargets.erase(CurrTarget);
				}
				else {
					++CurrTarget;
				}
			}
			// Find calls used as jumps.
			list<SMPInstr>::iterator InstIter = this->Instrs.begin();
			while (InstIter != this->Instrs.end()) {
				SMPitype InstFlow = InstIter->GetDataFlowType();
				if ((CALL == InstFlow) || (INDIR_CALL == InstFlow)) {
					InstIter->AnalyzeCallInst(this->FirstEA, this->FuncInfo.endEA);
				}
				++InstIter;
			}
		} // end if (FoundBadCallTarget)
	}

	this->MarkFunctionSafe();
} // end of SMPFunction::Analyze()

// For each instruction, mark the non-flags-reg DEFs as having live
//  metadata (mmStrata needs to fetch and track this metadata for this
//  instruction) or dead metadata (won't be used as addressing reg, won't
//  be stored to memory, won't be returned to caller).
void SMPFunction::AnalyzeMetadataLiveness(void) {
	bool changed;
	int BaseReg;
	int IndexReg;
	ushort ScaleFactor;
	ea_t offset;
	op_t BaseOp, IndexOp, ReturnOp, DefOp, UseOp;
	BaseOp.type = o_reg;
	IndexOp.type = o_reg;
	ReturnOp.type = o_reg;
	list<SMPInstr>::iterator CurrInst;
	set<DefOrUse, LessDefUse>::iterator CurrDef;
	set<DefOrUse, LessDefUse>::iterator CurrUse;
	set<DefOrUse, LessDefUse>::iterator NextUse;
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	bool DebugFlag = false;
	int IterationCount = 0;
#if SMP_DEBUG_DATAFLOW
	if (0 == strcmp("uw_frame_state_for", this->GetFuncName())) {
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		DebugFlag = true;
	}

	do {
		changed = false;
		if (DebugFlag) {
			msg("AnalyzeMetadataLiveness iteration count: %d \n", IterationCount);
		}
		for (CurrInst = this->Instrs.begin(); CurrInst != this->Instrs.end(); ++CurrInst) {
			SafeMemDest = false;  // true for some SafeFunc instructions
			// Skip the SSA marker instruction.
			if (NN_fnop == CurrInst->GetCmd().itype)
				continue;

			if (DebugFlag) {
				msg("Inst addr: %x \n", CurrInst->GetAddr());
			}
			CurrDef = CurrInst->GetFirstDef();
			while (CurrDef != CurrInst->GetLastDef()) {
				if (DEF_METADATA_UNANALYZED == CurrDef->GetMetadataStatus()) {
					DefOp = CurrDef->GetOp();
					// Handle special registers never used as address regs.
					if (DefOp.is_reg(X86_FLAGS_REG)
						|| ((o_trreg <= DefOp.type) && (o_xmmreg >= DefOp.type))) {
						CurrDef = CurrInst->SetDefMetadata(DefOp,
							DEF_METADATA_UNUSED);
						changed = true;
					}
					else if (DefOp.is_reg(R_sp) 
						|| (this->UseFP && DefOp.is_reg(R_bp))) {
						// Stack pointer register DEFs always have live
						//  metadata, but we don't need to propagate back
						//  through particular DEF-USE chains.
						CurrDef = CurrInst->SetDefMetadata(DefOp, DEF_METADATA_USED);
						changed = true;
					}
					else if ((o_mem <= DefOp.type) && (o_displ >= DefOp.type)) {
						// DEF is a memory operand. The addressing registers
						//  therefore have live metadata, and the memory metadata is live.
						// EXCEPTION: If the function is Safe, then direct stack writes
						//  to local variables (above the outgoing args area of the frame)
						//  are not live metadata, and there will be no indirect local frame
						//  writes, by definition of "safe." So, for safe funcs, only
						//  the o_mem (globals) and indirect writes are live metadata.
						if (this->SafeFunc && MDIsStackAccessOpnd(DefOp, this->UseFP)
							&& (!this->WritesAboveLocalFrame(DefOp))
							&& (!this->WritesToOutgoingArgs(DefOp))) {
							++CurrDef;
							SafeMemDest = true;
							continue;
						}
						CurrDef = CurrInst->SetDefMetadata(DefOp, DEF_METADATA_USED);
						changed = true;
						MDExtractAddressFields(DefOp, BaseReg, IndexReg,
							ScaleFactor, offset);
						if (R_none != BaseReg) {
							BaseOp.reg = MDCanonicalizeSubReg((ushort) BaseReg);
							if (BaseOp.is_reg(R_sp) 
								|| (this->UseFP && BaseOp.is_reg(R_bp))) {
								; // do nothing; DEF handled by case above
							}
							else {
								CurrUse = CurrInst->FindUse(BaseOp);
								if (CurrUse == CurrInst->GetLastUse()) {
									msg("ERROR: BaseReg %d not in USE list at %x for %s\n",
										BaseOp.reg, CurrInst->GetAddr(),
										CurrInst->GetDisasm());
								}
								assert(CurrUse != CurrInst->GetLastUse());
								if (this->IsGlobalName(BaseOp)) {
									changed |= this->PropagateGlobalMetadata(BaseOp,
										DEF_METADATA_USED, CurrUse->GetSSANum());
								}
								else {
									changed |= CurrInst->GetBlock()->PropagateLocalMetadata(BaseOp,
										DEF_METADATA_USED, CurrUse->GetSSANum());
								}
							}
						} // end if R_none != BaseReg
						if (R_none != IndexReg) {
							IndexOp.reg = MDCanonicalizeSubReg((ushort) IndexReg);
							if (IndexOp.is_reg(R_sp) 
								|| (this->UseFP && IndexOp.is_reg(R_bp))) {
								; // do nothing; DEF handled by case above
							}
							else {
								CurrUse = CurrInst->FindUse(IndexOp);
								if (CurrUse == CurrInst->GetLastUse()) {
									msg("ERROR: IndexReg %d not in USE list at %x for %s\n",
										IndexOp.reg, CurrInst->GetAddr(),
										CurrInst->GetDisasm());
								}
								assert(CurrUse != CurrInst->GetLastUse());
								if (0 != ScaleFactor) {
									; // mmStrata knows scaled reg is NUMERIC
									// ... its metadata is not fetched
								}
								else if (this->IsGlobalName(IndexOp)) {
									changed |= this->PropagateGlobalMetadata(IndexOp,
										DEF_METADATA_USED, CurrUse->GetSSANum());
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