SMPDataFlowAnalysis.cpp

/*
 * SMPDataFlowAnalysis.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/
 *
 */

//
// SMPDataFlowAnalysis.cpp
//
// This module contains common types an helper classes needed for the
//   SMP project (Software Memory Protection).
//

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

#include <cstring>

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

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

// Set these to 1 for debugging output
#define SMP_DEBUG_CONTROLFLOW 0  // tells what processing stage is entered
#define SMP_DEBUG_CHUNKS 1  // tracking down tail chunks for functions
#define SMP_DEBUG_FRAMEFIXUP 0  // Fixing up stack frame info the way we want the offsets
#define SMP_DEBUG_OPERAND_TYPES 1  // leave on; warnings that should never happen
#define STARS_DEBUG_DUMP_IDENTIFY_HIDDEN_OPERANDS 0 // print HIDDEN if operand.showed() is false

#if IDA_SDK_VERSION > 560
#define MAX_IDA_REG R_last
#else
#define MAX_IDA_REG 80
#endif

const char *RegNames[MAX_IDA_REG + 1] =
	{ "EAX", "ECX", "EDX", "EBX", "ESP", "EBP", "ESI", "EDI",
	  "R8", "R9", "R10", "R11", "R12", "R13", "R14", "R15",
	  "AL", "CL", "DL", "BL", "AH", "CH", "DH", "BH",
	  "SPL", "BPL", "SIL", "DIL", "EIP", "ES", "CS", "SS",
	  "DS", "FS", "GS", "CF", "ZF", "SF", "OF", "PF",
	  "AF", "TF", "IF", "DF", "EFLAGS", "FPU_ST0", "FPU_ST1", "FPU_ST2",
	  "FPU_ST3", "FPU_ST4", "FPU_ST5", "FPU_ST6", "FPU_ST7", "FPU_CTRL", "FPU_STAT", "FPU_TAGS",
      "MMX0", "MMX1", "MMX2", "MMX3", "MMX4", "MMX5", "MMX6", "MMX7",
      "XMM0", "XMM1", "XMM2", "XMM3", "XMM4", "XMM5", "XMM6", "XMM7",
      "XMM8", "XMM9", "XMM10", "XMM11", "XMM12", "XMM13", "XMM14", "XMM15",
      "MXCSR",
      "YMM0", "YMM1", "YMM2", "YMM3", "YMM4", "YMM5", "YMM6", "YMM7",
      "YMM8", "YMM9", "YMM10", "YMM11", "YMM12", "YMM13", "YMM14", "YMM15",
	  "REG_ERROR"
	};

const unsigned char RegSizes[MAX_IDA_REG + 1] =
	{ 4, 4, 4, 4, 4, 4, 4, 4,
	  8, 8, 8, 8, 8, 8, 8, 8,
	  1, 1, 1, 1, 1, 1, 1, 1,
	  1, 1, 1, 1, 4, 4, 4, 4,
	  4, 4, 4, 4, 4, 4, 4, 4,
	  4, 4, 4, 4, 4, 8, 8, 8,
	  8, 8, 8, 8, 8, 4, 4, 4,
      16, 16, 16, 16, 16, 16, 16, 16,
      16, 16, 16, 16, 16, 16, 16, 16,
      16, 16, 16, 16, 16, 16, 16, 16,
      4,
      32, 32, 32, 32, 32, 32, 32, 32,
      32, 32, 32, 32, 32, 32, 32, 32,
	  4
	};

const char *ErrorStrings[1] = { "ERROR_REG" };

const char *WordRegStrings[8] = { "AX", "CX", "DX", "BX", "SP", "BP", "SI", "DI" };

const char *QWordRegStrings[8] = { "RAX", "RCX", "RDX", "RBX", "RSP", "RBP", "RSI", "RDI" };

const char *SignednessStrings[4] = { "UNKNOWNSIGN", "SIGNED", "UNSIGNED", "UNKNOWNSIGN" };

const char *LeaSignednessStrings[4] = { "NOFLAGUNKNOWNSIGN", "NOFLAGSIGNED", "NOFLAGUNSIGNED", "NOFLAGUNKNOWNSIGN" };

// Distinguishes subword regs from their parent regs
const char *MDGetRegName(op_t RegOp) {
	if ((o_reg != RegOp.type) || (R_none == RegOp.reg) || (MAX_IDA_REG < RegOp.reg))
		return ErrorStrings[0];
	else if ((RegOp.dtyp == dt_word) && (RegOp.reg >= R_ax) && (RegOp.reg <= R_di)) {
		// 16-bit registers
		return WordRegStrings[RegOp.reg];
	}
	else if ((RegOp.dtyp == dt_qword) && (RegOp.reg >= R_ax) && (RegOp.reg <= R_di)) {
		// 64-bit registers
		return QWordRegStrings[RegOp.reg];
	}
	else {
		return RegNames[RegOp.reg];
	}
}


// Define instruction categories for data flow analysis.
SMPitype DFACategory[NN_last+1];
// Define instruction categories for data type analysis.
int SMPTypeCategory[NN_last+1];

// Define which instructions define and use the CPU flags.
bool SMPDefsFlags[NN_last + 1];
bool SMPUsesFlags[NN_last + 1];

// Hash a global name and SSA number into an int, for use in SMPFunction.GlobalDefAddrBySSA map
int HashGlobalNameAndSSA(op_t DefOp, int SSANum) { 
	assert(o_reg == DefOp.type);
	return ((SSANum << 16) | (DefOp.reg));
}

// Get the size in bytes of the data type of an operand.
size_t GetOpDataSize(op_t DataOp) {
	size_t DataSize;
	if (o_reg == DataOp.type) {
		DataSize = RegSizes[DataOp.reg];
		if (DataOp.dtyp == dt_word) {
			DataSize = 2;
#if 0
			SMP_msg("Found 16-bit register using dtyp field.\n");
#endif
		}
		else if (DataOp.dtyp == dt_qword) {
			DataSize = 8;
#if 0
			SMP_msg("Found 64-bit register using dtyp field.\n");
#endif
		}
		return DataSize;
	}
	switch (DataOp.dtyp) {
		case dt_byte:
			DataSize = 1;
			break;
		case dt_word:
			DataSize = 2;
			break;
		case dt_dword:
		case dt_float:
		case dt_code:
		case dt_unicode:
		case dt_string:
			DataSize = 4;
			break;
		case dt_double:
		case dt_qword:
			DataSize = 8;
			break;
		case dt_tbyte:
			DataSize = 10;
			break;
		case dt_packreal:
			DataSize = 12;
			break;
		case dt_byte16:
#if IDA_SDK_VERSION > 599
		case dt_ldbl:
#endif
			DataSize = 16;
			break;
		case dt_fword:
			DataSize = 6;
			break;
		case dt_3byte:
			DataSize = 3;
			break;
		default:
			SMP_msg("ERROR: unexpected data type %d in GetOpDataSize() :", DataOp.dtyp);
			PrintOperand(DataOp);
			SMP_msg("\n");
			DataSize = 4;
			break;
	}
	return DataSize;
} // end of GetOpDataSize()

// Return one of the bit width masks for the current operand.
//  Pass in DataSize in bytes if known, else pass in DataSize = 0.
unsigned short ComputeOperandBitWidthMask(op_t CurrOp, size_t DataSize) {
	unsigned short BitWidthMask = 32;
	if (0 == DataSize)
		DataSize = GetOpDataSize(CurrOp);
	if (4 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_32;
	else if (8 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_64;
	else if (1 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_8;
	else if (2 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_16;
	else if (16 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_128;
	else if (3 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_24;
	else if (6 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_48;
	else if (10 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_80;
	else if (12 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_96;
	else if (32 == DataSize)
		BitWidthMask = FG_MASK_BITWIDTH_256;
	else {
		SMP_msg("ERROR: Unknown DataSize: %zu bytes ", DataSize);
		PrintOperand(CurrOp);
		SMP_msg("\n");
	}
	return BitWidthMask;
} // end of ComputeOperandBitWidthMask()

// Compute largest bit width from a SignMiscInfo bit mask.
size_t LargestBitWidthFromMask(unsigned short WidthTypeInfo) {
	unsigned short BitWidthMask = WidthTypeInfo & FG_MASK_BITWIDTH_FIELDS;
	size_t LargestWidth = 0;

	// Go from highest bit width to lowest.
	if (BitWidthMask & FG_MASK_BITWIDTH_256)
		LargestWidth = 256;
	else if (BitWidthMask & FG_MASK_BITWIDTH_128)
		LargestWidth = 128;
	else if (BitWidthMask & FG_MASK_BITWIDTH_96)
		LargestWidth = 96;
	else if (BitWidthMask & FG_MASK_BITWIDTH_64)
		LargestWidth = 64;
	else if (BitWidthMask & FG_MASK_BITWIDTH_48)
		LargestWidth = 48;
	else if (BitWidthMask & FG_MASK_BITWIDTH_32)
		LargestWidth = 32;
	else if (BitWidthMask & FG_MASK_BITWIDTH_24)
		LargestWidth = 24;
	else if (BitWidthMask & FG_MASK_BITWIDTH_16)
		LargestWidth = 16;
	else if (BitWidthMask & FG_MASK_BITWIDTH_8)
		LargestWidth = 8;

	return LargestWidth;
} // end of LargestBitWidthFromMask()

// Is CurrOp a general purpose register? (not flags, instruction pointer, non-integer reg, etc.)
bool MDIsGeneralPurposeReg(op_t CurrOp) {
	// intel.hpp defines two ranges that are general purpose regs in enum RegNo.
	return ((o_reg == CurrOp.type) 
		&& (((CurrOp.reg >= R_ax) && (CurrOp.reg <= R_di))
			|| ((CurrOp.reg >= R_al) && (CurrOp.reg <= R_dil))));
}

// We maintain a list of the caller-saved regs for the current binary's ABI.
//  This differs from 32-bit to 64-bit x86 binaries, as well as across other ISAs.
list<uint16> STARS_MDCallerSavedRegs;

void MDInitializeCallerSavedRegs(void) {
	STARS_MDCallerSavedRegs.clear();
	bool x86_64_ISA_flag = false;
#ifdef __EA64__
	x86_64_ISA_flag = (STARS_ISA_Bitwidth == 64);
#endif
	if (!x86_64_ISA_flag) {
		// 32-bit x86 uses EAX, ECX, EDX as caller-saved.
		STARS_MDCallerSavedRegs.push_back(R_ax);
		STARS_MDCallerSavedRegs.push_back(R_cx);
		STARS_MDCallerSavedRegs.push_back(R_dx);
	}
	else {
		// 64-bit x86 uses EDI, ESI, EDX, ECX, R8 and R9
		//  in that order. After six arguments that fit into
		//  these regs, arguments are passed on the stack.
		// In addition, registers EAX, R10 and R11 are caller-saved
		//  but are not used to pass arguments.
		STARS_MDCallerSavedRegs.push_back(R_ax);
		STARS_MDCallerSavedRegs.push_back(R_cx);
		STARS_MDCallerSavedRegs.push_back(R_dx);
		STARS_MDCallerSavedRegs.push_back(R_si);
		STARS_MDCallerSavedRegs.push_back(R_di);
		STARS_MDCallerSavedRegs.push_back(R_r8);
		STARS_MDCallerSavedRegs.push_back(R_r9);
		STARS_MDCallerSavedRegs.push_back(R_r10);
		STARS_MDCallerSavedRegs.push_back(R_r11);
	}
	return;
}

list<uint16>::iterator GetFirstCallerSavedReg(void) {
	return STARS_MDCallerSavedRegs.begin();
}

list<uint16>::iterator GetLastCallerSavedReg(void) {
	return STARS_MDCallerSavedRegs.end();
}

// We maintain a list of the argument-passing regs for the current binary's ABI.
//  This differs from 32-bit to 64-bit x86 binaries, as well as across other ISAs.
//  The list is in order of argument position number. For x86-64, this means EDI,
//  ESI, EDX, ECX, R8, R9.
list<uint16> STARS_MDArgumentRegs;

void MDInitializeArgumentRegs(void) {
	bool x86_64_ISA_flag = false;
#ifdef __EA64__
	x86_64_ISA_flag = (STARS_ISA_Bitwidth == 64);
#endif
	if (x86_64_ISA_flag) {
		STARS_MDArgumentRegs.push_back(R_di);
		STARS_MDArgumentRegs.push_back(R_si);
		STARS_MDArgumentRegs.push_back(R_dx);
		STARS_MDArgumentRegs.push_back(R_cx);
		STARS_MDArgumentRegs.push_back(R_r8);
		STARS_MDArgumentRegs.push_back(R_r9);
	}
	else {
		STARS_MDArgumentRegs.clear();
	}
	return;
}

list<uint16>::iterator GetFirstArgumentReg(void) {
	return STARS_MDArgumentRegs.begin();
}

list<uint16>::iterator GetLastArgumentReg(void) {
	return STARS_MDArgumentRegs.end();
}

// Are operands equal?
bool IsEqOp(op_t Opnd1, op_t Opnd2) {
		if (Opnd1.type != Opnd2.type)
			return false;
		switch (Opnd1.type) {
			case o_void: return true;
			case o_reg: return ((Opnd1.reg == Opnd2.reg) && (Opnd1.dtyp == Opnd2.dtyp));
			case o_mem: return (Opnd1.addr == Opnd2.addr);
			case o_phrase: if (Opnd1.hasSIB && Opnd2.hasSIB) return ((Opnd1.sib == Opnd2.sib) && (Opnd1.specflag4 == Opnd2.specflag4));
						   else if (Opnd1.hasSIB || Opnd2.hasSIB) return false; // no SIB != has SIB
							else return (Opnd1.reg == Opnd2.reg); // neither has SIB; compare register, e.g. [ebx] to [edx]
			case o_displ: if (Opnd1.hasSIB && Opnd2.hasSIB)
							  return ((Opnd1.sib == Opnd2.sib) && (Opnd1.addr == Opnd2.addr) && (Opnd1.specflag4 == Opnd2.specflag4));
						  else if ((!Opnd1.hasSIB) && (!Opnd2.hasSIB))
							  return ((Opnd1.addr == Opnd2.addr) && (Opnd1.reg == Opnd2.reg));
							else return false; // no SIB != has SIB
			case o_imm: return (Opnd1.value == Opnd2.value);
			case o_far:  // fall through to o_near case
			case o_near: return (Opnd1.addr == Opnd2.addr);
			case o_trreg:  // fall through
			case o_dbreg:  // fall through
			case o_crreg:  // fall through
			case o_fpreg:  // fall through
			case o_mmxreg: // fall through
			case o_xmmreg: return (Opnd1.reg == Opnd2.reg); // no subword regs to deal with

			default: SMP_msg("ERROR: Unknown operand type in IsEqOp.\n"); return false;
		}; // end switch (Opnd1.type)}
} // end of function IsEqOp()

// Are operands equal, ignoring bitwidth differences for register operands?
bool IsEqOpIgnoreBitwidth(op_t Opnd1, op_t Opnd2) {
		if (Opnd1.type != Opnd2.type)
			return false;
		switch (Opnd1.type) {
			case o_void: return true;
			case o_reg: return (Opnd1.reg == Opnd2.reg);
			case o_mem: return (Opnd1.addr == Opnd2.addr);
			case o_phrase: if (Opnd1.hasSIB && Opnd2.hasSIB) return ((Opnd1.sib == Opnd2.sib) && (Opnd1.specflag4 == Opnd2.specflag4));
						   else if (Opnd1.hasSIB || Opnd2.hasSIB) return false; // no SIB != has SIB
							else return (Opnd1.reg == Opnd2.reg); // neither has SIB; compare register, e.g. [ebx] to [edx]
			case o_displ: if (Opnd1.hasSIB && Opnd2.hasSIB)
							  return ((Opnd1.sib == Opnd2.sib) && (Opnd1.addr == Opnd2.addr)  && (Opnd1.specflag4 == Opnd2.specflag4));
						  else if ((!Opnd1.hasSIB) && (!Opnd2.hasSIB))
							  return ((Opnd1.addr == Opnd2.addr) && (Opnd1.reg == Opnd2.reg));
							else return false; // no SIB != has SIB
			case o_imm: return (Opnd1.value == Opnd2.value);
			case o_far:  // fall through to o_near case
			case o_near: return (Opnd1.addr == Opnd2.addr);
			case o_trreg:  // fall through
			case o_dbreg:  // fall through
			case o_crreg:  // fall through
			case o_fpreg:  // fall through
			case o_mmxreg: // fall through
			case o_xmmreg: return (Opnd1.reg == Opnd2.reg); // no subword regs to deal with

			default: SMP_msg("ERROR: Unknown operand type in IsEqOpIgnoreBitwidth.\n"); return false;
		}; // end switch (Opnd1.type)}
} // end of function IsEqOpIgnoreBitwidth()

// We need to make subword registers equal to their containing registers when we
//  do comparisons, so that we will realize that register EAX is killed by a prior DEF
//  of register AL, for example, and vice versa. To keep sets ordered strictly,
//  we also have to make AL and AH be equal to each other as well as equal to EAX.
#define FIRST_x86_SUBWORD_REG R_al
#define LAST_x86_SUBWORD_REG R_bh
bool MDLessReg(const ushort Reg1, const ushort Reg2) {
	ushort SReg1 = MDCanonicalizeSubReg(Reg1);
	ushort SReg2 = MDCanonicalizeSubReg(Reg2);
	return (SReg1 < SReg2);
} // end of MDLessReg()

bool MDEqReg(const ushort Reg1, const ushort Reg2) {
	ushort SReg1 = MDCanonicalizeSubReg(Reg1);
	ushort SReg2 = MDCanonicalizeSubReg(Reg2);
	return (SReg1 == SReg2);
} // end of MDEqReg()

bool MDLessRegOpnd(const op_t RegOp1, const op_t RegOp2) {
	ushort SReg1 = MDCanonicalizeSubReg(RegOp1.reg);
	ushort SReg2 = MDCanonicalizeSubReg(RegOp2.reg);
	return ((SReg1 < SReg2) || ((SReg1 == SReg2) && (RegOp1.dtyp < RegOp2.dtyp)));
} // end of MDLessRegOpnd()

ushort MDCanonicalizeSubReg(const ushort Reg1) {
	bool Subword = ((Reg1 >= FIRST_x86_SUBWORD_REG) && (Reg1 <= LAST_x86_SUBWORD_REG));
	ushort SReg1 = Reg1;

	if (Subword) {
		// See enumeration RegNo in intel.hpp.
		if (SReg1 < 20)  // AL, CL, DL or BL
			SReg1 -= 16;
		else             // AH, CH, DH or BH
			SReg1 -= 20;
	}
	return SReg1;
} // end of MDCanonicalizeSubReg()


#if 0
// If TempOp is a register, call MDCanonicalizeSubReg() on it.
void CanonicalizeOpnd(op_t &TempOp) {
	if (o_reg == TempOp.type) {
		uint16 NewReg = MDCanonicalizeSubReg(TempOp.reg);
		if (TempOp.reg != NewReg) {
			TempOp.reg = NewReg;
			TempOp.dtyp = STARS_ISA_dtyp; // set to full reg width
		}
	}
}

#else
// If TempOp is a register, call MDCanonicalizeSubReg() on it.
void CanonicalizeOpnd(op_t &TempOp) {
	if (o_reg == TempOp.type) {
		if (4 > GetOpDataSize(TempOp)) {
			TempOp.reg = MDCanonicalizeSubReg(TempOp.reg);
			TempOp.dtyp = dt_dword; // set to normal reg width
		}
	}
}
#endif

bool MDIsStackOrFramePointerReg(op_t RegOp, bool UseFP) {
	bool PtrReg = false;
	if (o_reg == RegOp.type) {
		PtrReg = RegOp.is_reg(MD_STACK_POINTER_REG) || (UseFP && RegOp.is_reg(MD_FRAME_POINTER_REG));
	}
	return PtrReg;
}

// In SSA computations, we are storing the GlobalNames index into the op_t fields
//  n, offb, and offo. This function extracts an unsigned int from these three 8-bit
//  fields.
unsigned int ExtractGlobalIndex(op_t GlobalOp) {
	unsigned int index = 0;
	index |= (((unsigned int) GlobalOp.offo) & 0x000000ff);
	index <<= 8;
	index |= (((unsigned int) GlobalOp.offb) & 0x000000ff);
	index <<= 8;
	index |= (((unsigned int) GlobalOp.n) & 0x000000ff);
	return index;
}

void SetGlobalIndex(op_t *TempOp, size_t index) {
	TempOp->n = (char) (index & 0x000000ff);
	TempOp->offb = (char) ((index & 0x0000ff00) >> 8);
	TempOp->offo = (char) ((index & 0x00ff0000) >> 16);
	return;
}


bool MD_STARS_op256(const op_t &x)        // is VEX.L set?
{
  return ((x.specflag4 & STARS_VEXPR) != 0) && ((x.specflag4 & VEX_L) != 0);
}

bool MD_STARS_is_vsib(const op_t &x)  // does instruction use VSIB variant of the sib byte?
{
  return ((x.specflag4 & STARS_VSIB) != 0);
}

int MD_STARS_sib_base(const op_t &x)                    // get extended sib base
{
  int base = x.sib & 7;
#ifdef __EA64__
  if ( x.specflag4 & REX_B )
    base |= 8;
#endif
  return base;
}

regnum_t MD_STARS_sib_index(const op_t &x)                   // get extended sib index
{
  regnum_t index = regnum_t((x.sib >> 3) & 7);
#ifdef __EA64__
  if ( x.specflag4 & REX_X )
    index |= 8;
#endif
  if (MD_STARS_is_vsib(x))
    index += MD_STARS_op256(x) ? 81 /*R_ymm0*/ : 64 /*R_xmm0*/;
  return index;
}

// Return true if CurrOp could be an indirect memory reference.
bool MDIsIndirectMemoryOpnd(op_t CurrOp, bool UseFP) {
	bool indirect = false;
	if ((CurrOp.type != o_mem) && (CurrOp.type != o_phrase) && (CurrOp.type != o_displ))
		return false;

	if (CurrOp.hasSIB) {
		int BaseReg = MD_STARS_sib_base(CurrOp);
		short IndexReg = MD_STARS_sib_index(CurrOp);
		if ((R_none != IndexReg) && (MD_STACK_POINTER_REG != IndexReg)) { 
			if ((MD_FRAME_POINTER_REG == IndexReg) && UseFP)
				;
			else
				indirect = true;
		}
		if (0 != sib_scale(CurrOp))
			indirect = true;
		if (R_none != BaseReg) {
			if ((BaseReg == MD_FRAME_POINTER_REG) && (CurrOp.type == o_mem)) {
				; // EBP ==> no base register for o_mem type
			}
			else if ((BaseReg == MD_FRAME_POINTER_REG) && UseFP) 
				;  // EBP used as frame pointer for direct access
			else if (BaseReg == MD_STACK_POINTER_REG)
				;  // ESP used as stack pointer for direct access
			else
				indirect = true; // conservative; some register used for addressing
								// other than a stack or frame pointer
		}
	} // end if hasSIB
	else { // no SIB; can have base register only
		ushort BaseReg = CurrOp.reg;
		if (CurrOp.type == o_mem) { // no base register for o_mem
			if (!((0 == BaseReg) || (MD_FRAME_POINTER_REG == BaseReg))) {
				SMP_msg("base reg %d ignored \n", BaseReg);
			}
		}
		else if ((BaseReg == MD_FRAME_POINTER_REG) && UseFP) 
			;  // EBP used as frame pointer for direct access
		else if (BaseReg == MD_STACK_POINTER_REG)
			;  // ESP used as stack pointer for direct access
		else {
			indirect = true;
		}
	}

	return indirect;
} // end MDIsIndirectMemoryOpnd()

// Extract the base and index registers and scale factor and displacement from the
//  memory operand.
void MDExtractAddressFields(op_t MemOp, int &BaseReg, int &IndexReg, ushort &Scale, ea_t &Offset) {
	assert((MemOp.type == o_phrase) || (MemOp.type == o_displ) || (MemOp.type == o_mem));

	Scale = 0;
	BaseReg = R_none;
	IndexReg = R_none;
	Offset = MemOp.addr;

	if (MemOp.hasSIB) {
		BaseReg = MD_STARS_sib_base(MemOp);
		IndexReg = (int) MD_STARS_sib_index(MemOp);
		if (MD_STACK_POINTER_REG == IndexReg) // signifies no index register
			IndexReg = R_none;
		if (R_none != IndexReg) {
			Scale = (ushort) sib_scale(MemOp);
		}
		if (R_none != BaseReg) {
			if ((BaseReg == MD_FRAME_POINTER_REG) && (MemOp.type == o_mem)) {
				BaseReg = R_none;
				// **!!** BaseReg allowed for o_mem with SIB byte???
			}
		}
	}
	else { // no SIB byte; can have base reg but no index reg or scale factor
		BaseReg = (int) MemOp.reg;  // cannot be R_none for no SIB case
		if (MemOp.type == o_mem) {
			BaseReg = R_none; // no Base register for o_mem operands
		}
	}

	return;
} // end of MDExtractAddressFields()

// Is CurrOp a memory operand?
bool IsMemOperand(op_t CurrOp) {
	return ((o_mem == CurrOp.type) || (o_displ == CurrOp.type) || (o_phrase == CurrOp.type));
}

// MACHINE DEPENDENT: Is CurrOp the flags register?
bool MDIsFlagsReg(op_t CurrOp) {
	return ((o_reg == CurrOp.type) && CurrOp.is_reg(X86_FLAGS_REG));
}

// MACHINE DEPENDENT: Is register a stack pointer or frame pointer?
bool MDIsStackPtrReg(int RegNumber, bool UseFP) {
	return ((RegNumber == MD_STACK_POINTER_REG) || (UseFP && (RegNumber == MD_FRAME_POINTER_REG)));
}

// MACHINE DEPENDENT: Is operand a stack memory access?
bool MDIsStackAccessOpnd(op_t CurrOp, bool UseFP) {
	int BaseReg;
	int IndexReg;
	ushort ScaleFactor;
	ea_t offset;

	if ((o_displ != CurrOp.type) && (o_phrase != CurrOp.type)) {
		return false;
	}

	MDExtractAddressFields(CurrOp, BaseReg, IndexReg, ScaleFactor, offset);
	return MDIsStackPtrReg(BaseReg, UseFP);
} // end of MDIsStackAccessOpnd()

// MACHINE DEPENDENT: Is operand a direct stack memory access?
bool MDIsDirectStackAccessOpnd(op_t CurrOp, bool UseFP) {
	int BaseReg;
	int IndexReg;
	ushort ScaleFactor;
	ea_t offset;

	if ((o_displ != CurrOp.type) && (o_phrase != CurrOp.type)) {
		return false;
	}

	MDExtractAddressFields(CurrOp, BaseReg, IndexReg, ScaleFactor, offset);
	// When the IndexReg is
	return (MDIsStackPtrReg(BaseReg, UseFP) && (IndexReg == R_none));
} // end of MDIsDirectStackAccessOpnd()

// MACHINE DEPENDENT: Is operand trackable in data flow analyses (i.e. a direct stack memory access or a register?)
bool MDIsDataFlowOpnd(op_t CurrOp, bool UseFP) {
	return ((o_reg == CurrOp.type) || MDIsDirectStackAccessOpnd(CurrOp, UseFP));
}

// MACHINE DEPENDENT: Is operand a caller-saved register?
bool MDIsCallerSavedReg(op_t CurrOp) {
	if (o_reg != CurrOp.type)
		return false;
	ushort CurrReg = MDCanonicalizeSubReg(CurrOp.reg);
	return ((R_ax == CurrReg) || (R_cx == CurrReg) || (R_dx == CurrReg));
} // end of MDIsCallerSavedReg()

// DEBUG Print DEF and/or USE for an operand.
void PrintDefUse(ulong feature, int OpNum) {
	// CF_ macros number the operands from 1 to 6, while OpNum
	//  is a 0 to 5 index into the insn_t.Operands[] array.
	// OpNum == -1 is a signal that this is a DEF or USE or VarKillSet etc.
	//  operand and not an instruction operand.
	if (-1 == OpNum)
		return;
	switch (OpNum) {
		case 0:
			if (feature & CF_CHG1)
				SMP_msg(" DEF");
			if (feature & CF_USE1)
				SMP_msg(" USE");
			break;
		case 1:
			if (feature & CF_CHG2)
				SMP_msg(" DEF");
			if (feature & CF_USE2)
				SMP_msg(" USE");
			break;
		case 2:
			if (feature & CF_CHG3)
				SMP_msg(" DEF");
			if (feature & CF_USE3)
				SMP_msg(" USE");
			break;
		case 3:
			if (feature & CF_CHG4)
				SMP_msg(" DEF");
			if (feature & CF_USE4)
				SMP_msg(" USE");
			break;
		case 4:
			if (feature & CF_CHG5)
				SMP_msg(" DEF");
			if (feature & CF_USE5)
				SMP_msg(" USE");
			break;
		case 5:
			if (feature & CF_CHG6)
				SMP_msg(" DEF");
			if (feature & CF_USE6)
				SMP_msg(" USE");
			break;
	}
	return;
} // end PrintDefUse()

// DEBUG print SIB info for an operand.
void PrintSIB(op_t Opnd) {
	int BaseReg;
	int IndexReg;
	ushort ScaleFactor;
	ea_t offset;
#define NAME_LEN 5
	char BaseName[NAME_LEN] = {'N', 'o', 'n', 'e', '\0'};
	char IndexName[NAME_LEN] = {'N', 'o', 'n', 'e', '\0'};

	MDExtractAddressFields(Opnd, BaseReg, IndexReg, ScaleFactor, offset);

	if (BaseReg != R_none)
		SMP_strncpy(BaseName, RegNames[BaseReg], NAME_LEN - 1);

	if (IndexReg != R_none) {
		SMP_strncpy(IndexName, RegNames[IndexReg], NAME_LEN -1);
	}
	SMP_msg(" Base %s Index %s Scale %d Flag4 %d", BaseName, IndexName, ScaleFactor, Opnd.specflag4);
} // end PrintSIB()

// Annotations: concisely print SIB info for an operand.
void AnnotPrintSIB(op_t Opnd, bool HasOffset, FILE *OutFile) {
	int BaseReg;
	int IndexReg;
	ushort ScaleFactor;
	ea_t offset;
	char OutString[MAXSTR] = {'[', '\0'};
	char ScaleString[4];
	op_t BaseOp =  InitOp, IndexOp = InitOp;
	BaseOp.type = o_reg;
	IndexOp.type = o_reg;
#if 0
	BaseOp.dtyp = Opnd.dtyp;
	IndexOp.dtyp = Opnd.dtyp;
#endif

	MDExtractAddressFields(Opnd, BaseReg, IndexReg, ScaleFactor, offset);

	if (ScaleFactor > 0) {
		ScaleFactor = 1 << (ScaleFactor - 1);
		(void) SMP_snprintf(ScaleString, 4, "%d", ScaleFactor);
	}

	if (BaseReg != R_none) {
		BaseOp.reg = BaseReg;
		if (RegSizes[BaseReg] == 1)
			BaseOp.dtyp = dt_byte;
		(void) SMP_strncat(OutString, MDGetRegName(BaseOp), MAXSTR-1);
		if (IndexReg != R_none) {
			IndexOp.reg = IndexReg;
			if (RegSizes[IndexReg] == 1)
				IndexOp.dtyp = dt_byte;
			(void) SMP_strncat(OutString, "+", MAXSTR-1);
			(void) SMP_strncat(OutString, MDGetRegName(IndexOp), MAXSTR-1);
			if (ScaleFactor > 0) {
				(void) SMP_strncat(OutString, "*", MAXSTR-1);
				(void) SMP_strncat(OutString, ScaleString, MAXSTR-1);
			}
		}
	}
	else if (IndexReg != R_none) {
		IndexOp.reg = IndexReg;
		if (RegSizes[IndexReg] == 1)
			IndexOp.dtyp = dt_byte;
		(void) SMP_strncat(OutString, MDGetRegName(IndexOp), MAXSTR-1);
		if (ScaleFactor > 0) {
			(void) SMP_strncat(OutString, "*", MAXSTR-1);
			(void) SMP_strncat(OutString, ScaleString, MAXSTR-1);
		}
	}
	else {
		SMP_msg("ERROR: No BaseReg, no IndexReg in SIB\n");
	}
	if (!HasOffset) // can close the brackets around regs
		(void) SMP_strncat(OutString, "]", MAXSTR-1);
	SMP_fprintf(OutFile, " %s", OutString);
} // end AnnotPrintSIB()

// Annotations: concisely print SIB info for an operand.
void SPARKAnnotPrintSIB(op_t Opnd, bool HasOffset, FILE *OutFile) {
	int BaseReg;
	int IndexReg;
	ushort ScaleFactor;
	ea_t offset;
	char OutString[MAXSTR] = {'[', '\0'};
	char ScaleString[4];
	op_t BaseOp =  InitOp, IndexOp = InitOp;
	BaseOp.type = o_reg;
	IndexOp.type = o_reg;
#if 0
	BaseOp.dtyp = Opnd.dtyp;
	IndexOp.dtyp = Opnd.dtyp;
#endif

	MDExtractAddressFields(Opnd, BaseReg, IndexReg, ScaleFactor, offset);

	if (ScaleFactor > 0) {
		ScaleFactor = 1 << (ScaleFactor - 1);
		(void) SMP_snprintf(ScaleString, 4, "%d", ScaleFactor);
	}

	if (BaseReg != R_none) {
		BaseOp.reg = BaseReg;
		if (RegSizes[BaseReg] == 1)
			BaseOp.dtyp = dt_byte;
		(void) SMP_strncat(OutString, "TemplateX86.", MAXSTR-1);
		(void) SMP_strncat(OutString, MDGetRegName(BaseOp), MAXSTR-1);
		if (STARS_ISA_Bytewidth > GetOpDataSize(BaseOp)) {
			++SubwordAddressRegCount;
		}
		if (IndexReg != R_none) {
			IndexOp.reg = IndexReg;
			if (RegSizes[IndexReg] == 1)
				IndexOp.dtyp = dt_byte;
			(void) SMP_strncat(OutString, " + ", MAXSTR-1);
			(void) SMP_strncat(OutString, "TemplateX86.", MAXSTR-1);
			(void) SMP_strncat(OutString, MDGetRegName(IndexOp), MAXSTR-1);
			if (STARS_ISA_Bytewidth > GetOpDataSize(IndexOp)) {
				++SubwordAddressRegCount;
			}
			if (ScaleFactor > 0) {
				(void) SMP_strncat(OutString, "*", MAXSTR-1);
				(void) SMP_strncat(OutString, ScaleString, MAXSTR-1);
			}
		}
	}
	else if (IndexReg != R_none) {
		IndexOp.reg = IndexReg;
		if (RegSizes[IndexReg] == 1)
			IndexOp.dtyp = dt_byte;
		(void) SMP_strncat(OutString, "TemplateX86.", MAXSTR-1);
		(void) SMP_strncat(OutString, MDGetRegName(IndexOp), MAXSTR-1);
		if (STARS_ISA_Bytewidth > GetOpDataSize(IndexOp)) {
			++SubwordAddressRegCount;
		}
		if (ScaleFactor > 0) {
			(void) SMP_strncat(OutString, "*", MAXSTR-1);
			(void) SMP_strncat(OutString, ScaleString, MAXSTR-1);
		}
	}
	else {
		SMP_msg("ERROR: No BaseReg, no IndexReg in SIB\n");
	}
	if (!HasOffset) // can close the brackets around regs
		(void) SMP_strncat(OutString, "]", MAXSTR-1);
	SMP_fprintf(OutFile, " %s", OutString);
} // end SPARKAnnotPrintSIB()

// Debug: print one operand from an instruction or DEF or USE list.
void PrintOneOperand(op_t Opnd, ulong features, int OpNum) { 
	if (Opnd.type != o_void) {
		PrintOperand(Opnd);
		PrintDefUse(features, OpNum);
	}
	return;
} // end of PrintOneOperand()

// Debug: print one operand.
void PrintOperand(op_t Opnd) { 
	if (Opnd.type == o_void)
		return;
	else if (Opnd.type == o_mem) {
		SMP_msg(" Operand: memory : addr: %lx", (unsigned long) Opnd.addr);
		if (Opnd.hasSIB) {
			PrintSIB(Opnd);
		}
	}
	else if (Opnd.type == o_phrase) {
		SMP_msg(" Operand: memory phrase :");
		if (Opnd.hasSIB) { // has SIB info
			PrintSIB(Opnd);
		}
		else { // no SIB info
			ushort BaseReg = Opnd.phrase;
			SMP_msg(" reg %s", RegNames[BaseReg]);
		}
		if (Opnd.addr != 0) {
			SMP_msg(" \n WARNING: addr for o_phrase type: %lx\n", (unsigned long) Opnd.addr);
		}
	}
	else if (Opnd.type == o_displ) {
		SMP_msg(" Operand: memory displ :");
		ea_t offset = Opnd.addr;
		int SignedOffset = (int) offset;
		if (Opnd.hasSIB) {
			PrintSIB(Opnd);
			SMP_msg(" displ %d", SignedOffset);
		}
		else {
			ushort BaseReg = Opnd.reg;
			SMP_msg(" reg %s displ %d", RegNames[BaseReg], SignedOffset);
		}
	}
	else if (Opnd.type == o_reg) {
		SMP_msg(" Operand: register %s", MDGetRegName(Opnd));
	}
	else if (Opnd.type == o_imm) {
		SMP_msg(" Operand: immed %ld", (long) Opnd.value);
	}
	else if (Opnd.type == o_far) {
		SMP_msg(" Operand: FarPtrImmed addr: %lx", (unsigned long) Opnd.addr);
	}
	else if (Opnd.type == o_near) {
		SMP_msg(" Operand: NearPtrImmed addr: %lx", (unsigned long) Opnd.addr);
	}
	else if (Opnd.type == o_trreg) {
		SMP_msg(" Operand: TaskReg reg: %d", Opnd.reg);
	}
	else if (Opnd.type == o_dbreg) {
		SMP_msg(" Operand: DebugReg reg: %d", Opnd.reg);
	}
	else if (Opnd.type == o_crreg) {
		SMP_msg(" Operand: ControlReg reg: %d", Opnd.reg);
	}
	else if (Opnd.type == o_fpreg) {
		SMP_msg(" Operand: FloatReg reg: %d", Opnd.reg);
	}
	else if (Opnd.type == o_mmxreg) {
		SMP_msg(" Operand: MMXReg reg: %d", Opnd.reg);
	}
	else if (Opnd.type == o_xmmreg) {
		SMP_msg(" Operand: XMMReg reg: %d", Opnd.reg);
	}
	else {
		SMP_msg(" Operand: unknown");
	}
#if STARS_DEBUG_DUMP_IDENTIFY_HIDDEN_OPERANDS
	if (!(Opnd.showed()))
		SMP_msg(" HIDDEN ");
#endif
	return;
} // end of PrintOperand()

// Print an operand that has no features flags or operand position number, such
//  as the op_t types found in lists and sets throughout the blocks, phi functions, etc.
void PrintListOperand(op_t Opnd, int SSANum) {
	if (Opnd.type != o_void) {
		PrintOperand(Opnd);
		SMP_msg(" SSANum: %d ", SSANum);
	}
	return;
} // end of PrintListOperand()

// Annotations: concisely print one operand.
void AnnotPrintOperand(op_t Opnd, FILE *OutFile) { 
	op_t BaseOp = InitOp;
	op_t IndexOp = InitOp;
	BaseOp.type = o_reg;
	IndexOp.type = o_reg;
#if 0
	BaseOp.dtyp = Opnd.dtyp;
	IndexOp.dtyp = Opnd.dtyp;
#endif

	if (Opnd.type == o_mem) {
		SMP_fprintf(OutFile, " %lx", (unsigned long) Opnd.addr);
		if (Opnd.hasSIB) {
			AnnotPrintSIB(Opnd, false, OutFile);
		}
	}
	else if (Opnd.type == o_phrase) {
		if (Opnd.hasSIB) { // has SIB info