SMPInstr.cpp

#if SMP_BASEREG_POINTER_TYPE
	// Some instructions are analyzed outside of any function or block when fixing up
	//  the IDB, so we have to assume the block and func pointers might be NULL.
	if ((NULL != this->BasicBlock) && (NULL != this->BasicBlock->GetFunc()))
		UseFP = this->BasicBlock->GetFunc()->UsesFramePointer();
#endif

	if (DebugFlag) {
		msg("DEBUG: UseFP = %d\n", UseFP);
	}

	for (OpNum = 0; OpNum < UA_MAXOP; ++OpNum) {
		op_t Opnd = SMPcmd.Operands[OpNum];
		if ((Opnd.type == o_phrase) || (Opnd.type == o_displ) || (Opnd.type == o_mem)) {
			MDExtractAddressFields(Opnd, BaseReg, IndexReg, ScaleFactor, displacement);
			SingleAddressReg = ((0 == displacement) 
				&& ((R_none == BaseReg) || (R_none == IndexReg)));
			if (R_none != IndexReg) { 
				op_t IndexOpnd = Opnd; // Init to current operand field values
				IndexOpnd.type = o_reg; // Change type and reg fields
				IndexOpnd.reg = (ushort) IndexReg;
				IndexOpnd.hasSIB = 0;
				IndexOpnd.set_showed();
				// We want to map AH, AL, and AX to EAX, etc. throughout our data flow
				//  analysis and type inference systems.
				IndexOpnd.reg = MDCanonicalizeSubReg(IndexOpnd.reg);
				if (0 == ScaleFactor)
					this->Uses.SetRef(IndexOpnd);
				else { // scaling == shift ==> NUMERIC
					HasIndexReg = true;
					this->Uses.SetRef(IndexOpnd, NUMERIC);
				}
			}
			if (R_none != BaseReg) {
				op_t BaseOpnd = Opnd; // Init to current operand field values
				BaseOpnd.type = o_reg; // Change type and reg fields
				BaseOpnd.reg = (ushort) BaseReg;
				BaseOpnd.hasSIB = 0;
				BaseOpnd.set_showed();
				// We want to map AH, AL, and AX to EAX, etc. throughout our data flow
				//  analysis and type inference systems.
				BaseOpnd.reg = MDCanonicalizeSubReg(BaseOpnd.reg);
				RefType = UNINIT;
#if SMP_BASEREG_POINTER_TYPE
				// R_sp and R_bp will get type STACKPTR in SMPInstr::SetImmedTypes().
				//  Other registers used as base registers should get their USEs as
				//  base registers typed as POINTER, which might get refined later
				//  to STACKPTR, GLOBALPTR, HEAPPTR, etc.
				// NOTE: the NN_lea opcode is often used without a true base register.
				//  E.g. lea eax,[eax+eax+5] is an x86 idiom for eax:=eax*2+5, which
				//  could not be done in one instruction without using the addressing
				//  modes of the machine to do the arithmetic. We don't want to set the
				//  USE of EAX to POINTER in this case, so we will conservatively skip
				//  all lea instructions here.
				// We cannot be sure that a register is truly a base register unless
				//  there is also an index register. E.g. with reg+displacement, we
				//  could have memaddr+indexreg or basereg+offset, depending on what
				//  the displacement is. The exception is if there is no offset and only
				//  one addressing register, e.g. mov eax,[ebx].
				if (BaseOpnd.is_reg(R_sp) || (UseFP && BaseOpnd.is_reg(R_bp))
					|| leaInst || (!HasIndexReg && !SingleAddressReg)) {
					;
				}
				else {
					RefType = POINTER;
				}
#endif
				this->Uses.SetRef(BaseOpnd, RefType);
			} // end if R_none != BaseReg
		} // end if (o_phrase or o_displ operand)
	} // end for (all operands)

	// The lea (load effective address) instruction looks as if it has
	//  a memory USE:  lea ebx,[edx+esi]
	//  However, this instruction is really just: ebx := edx+esi
	//  Now that the above code has inserted the "addressing" registers
	//  into the USE list, we should remove the "memory USE".
	if (leaInst) {
		set<DefOrUse, LessDefUse>::iterator CurrUse;
		for (CurrUse = this->GetFirstUse(); CurrUse != this->GetLastUse(); ++CurrUse) {
			op_t UseOp = CurrUse->GetOp();
			if ((o_mem <= UseOp.type) && (o_displ >= UseOp.type)) {
				this->EraseUse(CurrUse);
				break;
			}
		}
	}

	// Next, handle repeat prefices in the instructions. The Intel REPE/REPZ prefix
	//  is just the text printed for SCAS/CMPS instructions that have a REP prefix.
	//  Only two distinct prefix codes are actually defined: REP and REPNE/REPNZ, and
	//  REPNE/REPNZ only applies to SCAS and CMPS instructions.
	bool HasRepPrefix = (0 != (this->SMPcmd.auxpref & aux_rep));
	bool HasRepnePrefix = (0 != (this->SMPcmd.auxpref & aux_repne));
	if (HasRepPrefix && HasRepnePrefix)
		msg("REP and REPNE both present at %x %s\n", this->GetAddr(), this->GetDisasm());
	if (HasRepPrefix || HasRepnePrefix) {
		// All repeating instructions use ECX as the countdown register.
		op_t BaseOpnd = InitOp;
		BaseOpnd.type = o_reg; // Change type and reg fields
		BaseOpnd.reg = R_cx;
		BaseOpnd.clr_showed();
		this->Defs.SetRef(BaseOpnd, NUMERIC);
		this->Uses.SetRef(BaseOpnd, NUMERIC);
	}
	if ((this->SMPcmd.itype == NN_cmps) || (this->SMPcmd.itype == NN_scas)
		|| (this->SMPcmd.itype == NN_movs) || (this->SMPcmd.itype == NN_stos)) {
		// ESI and EDI are USEd and DEFed to point to source and dest strings for CMPS/MOVS.
		//  Only EDI is involved with SCAS/STOS.
		op_t BaseOpnd = InitOp;
		BaseOpnd.type = o_reg; // Change type and reg fields
		BaseOpnd.clr_showed();
		if ((this->SMPcmd.itype == NN_cmps) || (this->SMPcmd.itype == NN_movs)) {
			BaseOpnd.reg = R_si;
			this->Defs.SetRef(BaseOpnd, POINTER);
			this->Uses.SetRef(BaseOpnd, POINTER);
		}
		BaseOpnd.reg = R_di;
		this->Defs.SetRef(BaseOpnd, POINTER);
		this->Uses.SetRef(BaseOpnd, POINTER);
	}

	// Now, handle special instruction categories that have implicit operands.
	if (NN_cmpxchg == this->SMPcmd.itype) {
		// x86 Compare and Exchange conditionally sets EAX. We must keep data flow analysis
		//  sound by declaring that EAX is always a DEF.
		this->MDAddRegDef(R_ax, false);
	} // end if NN_cmpxchg
	else if (this->MDIsPopInstr() || this->MDIsPushInstr() || this->MDIsReturnInstr()) {
		// IDA does not include the stack pointer in the DEFs or USEs.
		this->MDAddRegDef(R_sp, false);
		this->MDAddRegUse(R_sp, false);
		if (!this->MDIsReturnInstr()) {
			// We always reference [esp+0] or [esp-4], so add it to the DEF or USE list.
			op_t StackOp = InitOp;
			StackOp.type = o_displ;
			StackOp.reg = R_sp;
			if (this->MDIsPopInstr()) {
				StackOp.addr = 0;  // [ESP+0]
				this->Uses.SetRef(StackOp);  // USE
			}
			else {
				StackOp.addr = (ea_t) -4;  // [ESP-4]
				this->Defs.SetRef(StackOp); // DEF
			}
		}
	}
#if SMP_CALL_TRASHES_REGS
	else if ((this->type == CALL) || (this->type == INDIR_CALL)) {
		// We want to add the caller-saved registers to the USEs and DEFs lists
		this->MDAddRegDef(R_ax, false);
		this->MDAddRegDef(R_cx, false);
		this->MDAddRegDef(R_dx, false);
		this->MDAddRegUse(R_ax, false);
		this->MDAddRegUse(R_cx, false);
		this->MDAddRegUse(R_dx, false);
#if 1
		if (this->MDIsInterruptCall()) {
#endif
			this->MDAddRegDef(R_bx, false);
			this->MDAddRegUse(R_bx, false);
#if 1
		}
#endif
	}
#endif
	else if (this->MDIsEnterInstr() || this->MDIsLeaveInstr()) {
		// Entire function prologue or epilogue microcoded.
		this->MDAddRegDef(R_sp, false);
		this->MDAddRegUse(R_sp, false);
		this->MDAddRegDef(R_bp, false);
		this->MDAddRegUse(R_bp, false);
	}
	else if (this->SMPcmd.itype == NN_maskmovq) {
		this->MDAddRegUse(R_di, false, POINTER);
	}
	else if (8 == this->GetOptType()) {
		// This category implicitly writes to EDX:EAX.
		this->MDAddRegDef(R_dx, false);
		this->MDAddRegDef(R_ax, false);
	} // end else if (8 == GetOptType)
	else if (7 == this->GetOptType()) {
		// Category 7 instructions sometimes write implicitly to EDX:EAX or DX:AX.
		//  DX is the same as EDX to IDA Pro (and SMP); ditto for EAX and AX.
		// DIV, IDIV, and MUL all have hidden EAX or AX operands (hidden in the IDA Pro
		//  sense, because they are not displayed in the disassembly text). For example:
		//  mul ebx means EDX:EAX <-- EAX*EBX, and mul bx means DX:AX <-- AX*BX. If the
		//  source operand is only 8 bits wide, there is room to hold the result in AX
		//  without using DX:  mul bl means AX <-- AL*BL.
		// IMUL has forms with a hidden EAX or AX operand and forms with no implicit
		//  operands:  imul ebx means EDX:EAX <-- EAX*EBX, but imul ebx,edx means that
		//  EBX*EDX gets truncated and the result placed in EBX (no hidden operands).
		for (OpNum = 0; OpNum < UA_MAXOP; ++OpNum) {
			op_t TempUse = SMPcmd.Operands[OpNum];
			if (!TempUse.showed()) { // hidden operand
				if (TempUse.is_reg(R_ax)) { // not R_al, so it is not 8 bits
					if ((NN_div == this->SMPcmd.itype) || (NN_idiv == this->SMPcmd.itype)) {
						this->MDAddRegUse(R_dx, false);
					}
					this->MDAddRegDef(R_ax, false);
					this->MDAddRegDef(R_dx, false);
				}
			}
		}
	} // end else if (7 == OptType)

#if 0
	// The floating point instructions in type categories 14 and 15 often USE and DEF
	//  the floating point register stack, e.g. pushing a value onto that stack is a
	//  massive copy downward of stack locations. We don't really care about the USE of
	//  the stack if the value being pushed came from elsewhere than the stack. For example,
	//  an "fld" opcode pushes its source onto the stack. We build RTLs with a simple
	//  move structure, but the RTL building can be fooled by seeing two "source" operands
	//  in the USE list.
	if ((14 == SMPTypeCategory[this->SMPcmd.itype])
		|| (15 == SMPTypeCategory[this->SMPcmd.itype])) {
	}
#endif

#if 0  // Not true for LOOP instructions that use only the ECX counter register.
	if (this->type == COND_BRANCH) {
		assert(SMPUsesFlags[this->SMPcmd.itype]);
	}
#endif
	// The return value register EAX is not quite like a caller-save or callee-save
	//  register (technically, it is caller-save). Within a callee, it might appear
	//  that EAX has become dead by the time a return instruction is reached, but
	//  the USE that would make it not dead is in the caller. To prevent type inference
	//  from mistakenly thinking that all USEs of EAX have been seen in the callee,
	//  we add EAX to the USE list for all return instructions, as well as for all
	//  tail calls, which are essentially returns in terms of data flow analysis.
	// This USE of EAX will always be of type UNINIT unless its DEF has a known type
	//  that propagates to it. Thus, it will prevent an invalid back inference of the
	//  DEF type from "all" USE types that are visible in the callee; even if they
	//  were all NUMERIC, this return USE will be UNINIT and inhibit the invalid
	//  type inference. EAX could be loaded with a pointer from memory, for example,
	//  and USEd only in a comparison instruction, making it falsely appear to be
	//  a NUMERIC, without this extra USE at the return instruction.
	// Because some of the library functions pass values around in EBX, EDI, etc.,
	//  we will add these general purpose registers to the USE list for returns
	//  in order to prevent erroneous analyses of dead registers or unused
	//  metadata.
	if (this->type == RETURN) {
		this->MDAddRegUse(R_ax, false);
		this->MDAddRegUse(R_bx, false);
		this->MDAddRegUse(R_cx, false);
		this->MDAddRegUse(R_dx, false);
#if 0   // need to solve phase ordering problem first
		if (!UseFP)
#endif
			this->MDAddRegUse(R_bp, false);
		this->MDAddRegUse(R_si, false);
		this->MDAddRegUse(R_di, false);
	}

	// Next, add the flags register to the DEFs and USEs for those instructions that
	//  are marked as defining or using flags.
	if (!this->DefsFlags && SMPDefsFlags[this->SMPcmd.itype]) {
		this->MDAddRegDef(X86_FLAGS_REG, false);
		this->DefsFlags = true;
	}
	if (!this->UsesFlags && SMPUsesFlags[this->SMPcmd.itype]) {
		this->MDAddRegUse(X86_FLAGS_REG, false);
		this->UsesFlags = true;
	}

#if 1
	if (this->MDIsNop()) {
		// Clear the DEFs and USEs for no-ops.
		this->Defs.clear();
		this->Uses.clear();
	}
#endif

	if (DebugFlag) {
		msg("DEBUG after MDFixupDefUseLists:\n");
		this->Dump();
	}
	return;
} // end of SMPInstr::MDFixupDefUseLists()

// If we can definitely identify which part of the addressing expression
//  used in MemOp is the POINTER type, and it is not a STACKPTR or GLOBALPTR
//  immediate, set the USE type for that register to POINTER and return true.
//  If we can find definite NUMERIC addressing registers that are not already
//  typed as NUMERIC, set their USE types to NUMERIC and return true.
bool SMPInstr::MDFindPointerUse(op_t MemOp, bool UseFP) {
	bool changed = false;
	int BaseReg;
	int IndexReg;
	op_t BaseOp = InitOp;
	op_t IndexOp = InitOp;
	SMPOperandType BaseType = UNKNOWN;
	SMPOperandType IndexType = UNKNOWN;
	ushort ScaleFactor;
	ea_t offset;
	set<DefOrUse, LessDefUse>::iterator BaseIter;
	set<DefOrUse, LessDefUse>::iterator IndexIter;

	if (NN_lea == this->SMPcmd.itype)
		return false;  // lea instruction really has no memory operands
	if (NN_fnop == this->SMPcmd.itype)
		return false;  // SSA marker instruction

	MDExtractAddressFields(MemOp, BaseReg, IndexReg, ScaleFactor, offset);
	if (R_none != IndexReg) {
		IndexOp.type = o_reg;
		IndexOp.reg = MDCanonicalizeSubReg((ushort) IndexReg);
		IndexIter = this->FindUse(IndexOp);
		assert(IndexIter != this->GetLastUse());
		IndexType = IndexIter->GetType();
	}
	if (R_none != BaseReg) {
		BaseOp.type = o_reg;
		BaseOp.reg = MDCanonicalizeSubReg((ushort) BaseReg);
		BaseIter = this->FindUse(BaseOp);
		assert(BaseIter != this->GetLastUse());
		BaseType = BaseIter->GetType();
	}
	if ((R_sp == BaseReg) || (UseFP && (R_bp == BaseReg))) {
		if ((R_none != IndexReg) && (!IsNumeric(IndexType))) {
			// We have an indexed access into the stack frame.
			//  Set IndexReg USE type to NUMERIC.
			changed = true;
			IndexIter = this->SetUseType(IndexOp, NUMERIC);
			assert(IndexIter != this->GetLastUse());
		}
		return changed; // stack accesses will get STACKPTR type in SetImmedTypes()
	}
	if ((R_sp == IndexReg) || (UseFP && (R_bp == IndexReg))) {
		if ((R_none != BaseReg) && (!IsNumeric(BaseType))) {
			// We have an indexed access into the stack frame.
			//  Set BaseReg USE type to NUMERIC.
			// Note that BaseReg is really an IndexReg and vice versa.
			changed = true;
			BaseIter = this->SetUseType(BaseOp, NUMERIC);
			assert(BaseIter != this->GetLastUse());
			msg("WARNING: BaseReg is index, IndexReg is base: %s\n",
				this->GetDisasm());
		}
		return changed; // stack accesses will get STACKPTR type in SetImmedTypes()
	}
	if (IsImmedGlobalAddress(offset)) {
		if ((R_none != IndexReg) && (!IsNumeric(IndexType))) {
			// We have an indexed access into a global.
			//  Set IndexReg USE type to NUMERIC.
			changed = true;
			IndexIter = this->SetUseType(IndexOp, NUMERIC);
			assert(IndexIter != this->GetLastUse());
		}
		if ((R_none != BaseReg) && (!IsNumeric(BaseType))) {
			// We have an indexed access into a global.
			//  Set BaseReg USE type to NUMERIC.
			// Note that BaseReg is really an index register.
			changed = true;
			BaseIter = this->SetUseType(BaseOp, NUMERIC);
			assert(BaseIter != this->GetLastUse());
			msg("WARNING: BaseReg used as index: %s\n", this->GetDisasm());
		}
		return changed;  // handled in SetImmedTypes()
	}

	// At this point, we must have a base address in a register, not used
	//  to directly address the stack or a global.
	if ((0 < ScaleFactor) || (R_none == IndexReg)) {
		// IndexReg is scaled, meaning it is NUMERIC, so BaseReg must
		//  be a POINTER; or IndexReg is not present, so BaseReg is the
		//  only possible holder of an address.
		if (R_none != BaseReg) {
			if (UNINIT == BaseIter->GetType()) {
				changed = true;
				BaseIter = this->SetUseType(BaseOp, POINTER);
				assert(BaseIter != this->GetLastUse());
			}
		}
	}
	else if (R_none == BaseReg) {
		// We have an unscaled IndexReg and no BaseReg and offset was
		//  not a global offset, so IndexReg must be a POINTER.
		if (R_none != IndexReg) {
			if (UNINIT == IndexType) {
				changed = true;
				IndexIter = this->SetUseType(IndexOp, POINTER);
				assert(IndexIter != this->GetLastUse());
			}
		}
	}
	else { // We have BaseReg and an unscaled IndexReg.
		// The only hope for typing something like [ebx+edx] is for
		//  one register to already be typed NUMERIC, in which case
		//  the other one must be a POINTER, or if one register is
		//  already POINTER, then the other one must be NUMERIC.
		if (IsNumeric(BaseType)) {
			if (UNINIT == IndexType) {
				// Set to POINTER or PROF_POINTER
				changed = true;
				IndexIter = this->SetUseType(IndexOp, POINTER);
				assert(IndexIter != this->GetLastUse());
			}
			else if (IsNumeric(IndexType)) {
				msg("ERROR: BaseReg and IndexReg both NUMERIC at %x: %s\n",
					this->address, this->GetDisasm());
			}
		}
		else { // BaseReg was not NUMERIC
			if (UNINIT == BaseType) { // BaseReg is UNINIT
				if (IsNumeric(IndexType)) {
					changed = true;
					BaseIter = this->SetUseType(BaseOp, POINTER);
					assert(BaseIter != this->GetLastUse());
				}
				else if (IsDataPtr(IndexType)) {
					// IndexReg is POINTER, so make BaseReg NUMERIC.
					changed = true;
					BaseIter = this->SetUseType(BaseOp, NUMERIC);
					assert(BaseIter != this->GetLastUse());
				}
			}
			else if (IsDataPtr(BaseType)) {
				// BaseReg was a pointer type. IndexReg must be NUMERIC.
				if (UNINIT == IndexType) {
					changed = true;
					IndexIter = this->SetUseType(IndexOp, NUMERIC);
					assert(IndexIter != this->GetLastUse());
				}
				else if (IsDataPtr(IndexType)) {
					msg("ERROR: BaseReg and IndexReg both POINTER at %x: %s\n",
						this->address, this->GetDisasm());
				}
			}
		}
	}

	return changed;
} // end of SMPInstr::MDFindPointerUse()

// Are all DEFs typed to something besides UNINIT?
bool SMPInstr::AllDEFsTyped(void) {
	bool FoundUNINIT = false;
	set<DefOrUse, LessDefUse>::iterator DefIter;
	for (DefIter = this->GetFirstDef(); DefIter != this->GetLastDef(); ++DefIter) {
		if (IsEqType(UNINIT, DefIter->GetType())) {
			FoundUNINIT = true;
			break;
		}
	}
	return (!FoundUNINIT);
} // end of SMPInstr::AllDEFsTyped()

// Are all USEs typed to something besides UNINIT?
bool SMPInstr::AllUSEsTyped(void) {
	bool FoundUNINIT = false;
	set<DefOrUse, LessDefUse>::iterator UseIter;
	for (UseIter = this->GetFirstUse(); UseIter != this->GetLastUse(); ++UseIter) {
		if (IsEqType(UNINIT, UseIter->GetType())) {
			FoundUNINIT = true;
			break;
		}
	}
	return (!FoundUNINIT);
} // end of SMPInstr::AllUSEsTyped()

// Set the type of all immediate operands found in the USE set.
// Set all flags and floating point register USEs and DEFs to NUMERIC also.
void SMPInstr::SetImmedTypes(bool UseFP) {
	set<DefOrUse, LessDefUse>::iterator CurrUse;
	set<DefOrUse, LessDefUse>::iterator CurrDef;
	op_t UseOp;
	op_t DefOp;
	uval_t ImmVal;
	bool DebugFlag = false;
#if SMP_VERBOSE_DEBUG_BUILD_RTL
	DebugFlag = DebugFlag || (this->address == 0x805cd52) || (this->address == 0x805cd56);
	DebugFlag |= (0 == strncmp("__libc_csu_fini", this->BasicBlock->GetFunc()->GetFuncName(), 15));
#endif

	CurrUse = this->GetFirstUse();
	while (CurrUse != this->GetLastUse()) {
		UseOp = CurrUse->GetOp();
		if (DebugFlag) {
			msg("SetImmedTypes USE: ");
			PrintOperand(UseOp);
			msg("\n");
		}
		if (o_imm == UseOp.type) {
			ImmVal = UseOp.value;
			if (IsImmedGlobalAddress((ea_t) ImmVal)) {
				if (DebugFlag) msg("Setting to GLOBALPTR\n");
				CurrUse = this->SetUseType(UseOp, GLOBALPTR);
			}
			else if (this->Interrupt || IsImmedCodeAddress((ea_t) ImmVal)) {
				if (DebugFlag) msg("Setting to CODEPTR\n");
				CurrUse = this->SetUseType(UseOp, CODEPTR);
			}
			else { // NUMERIC
				if (DebugFlag) msg("Setting to NUMERIC\n");
				CurrUse = this->SetUseType(UseOp, NUMERIC);
			}
		}
		else if (o_reg == UseOp.type) {
			if (UseOp.is_reg(X86_FLAGS_REG)) {
				if (DebugFlag) msg("Setting flags reg to NUMERIC\n");
				CurrUse = this->SetUseType(UseOp, NUMERIC);
			}
#if 1
			else if (UseOp.is_reg(R_sp) || (UseFP && UseOp.is_reg(R_bp))) {
				if (DebugFlag) msg("Setting reg to STACKPTR\n");
				CurrUse = this->SetUseType(UseOp, STACKPTR);
			}
#endif
		}
#if 0  // could these registers have pointers in them?
		else if ((o_trreg == UseOp.type) ||(o_dbreg == UseOp.type) || (o_crreg == UseOp.type)) {
			if (DebugFlag) msg("Setting special reg to NUMERIC\n");
			CurrUse = this->SetUseType(UseOp, NUMERIC);
		}
#endif
		else if ((o_fpreg == UseOp.type) || (o_mmxreg == UseOp.type) || (o_xmmreg == UseOp.type)) {
			if (DebugFlag) msg("Setting floating point reg to NUMERIC\n");
			CurrUse = this->SetUseType(UseOp, NUMERIC);
		}
		else if ((o_mem == UseOp.type) || (o_phrase == UseOp.type) || (o_displ == UseOp.type)) {
			// For memory operands, we need to identify the POINTER value that
			//  is used in the addressing mode, if possible.
			(void) this->MDFindPointerUse(UseOp, UseFP);
		}
		++CurrUse;
	} // end while all USEs via CurrUse

	CurrDef = this->GetFirstDef();
	while (CurrDef != this->GetLastDef()) {
		DefOp = CurrDef->GetOp();
		if (DebugFlag) {
			msg("SetImmedTypes DEF: ");
			PrintOperand(DefOp);
			msg("\n");
		}
		if (DebugFlag) msg("FuncName: %s\n", this->BasicBlock->GetFunc()->GetFuncName());
		if (o_reg == DefOp.type) {
			if (DefOp.is_reg(X86_FLAGS_REG)) {
				if (DebugFlag) msg("Setting flags reg DEF to NUMERIC\n");
				CurrDef = this->SetDefType(DefOp, NUMERIC);
				// No need to propagate this DEF type, as all flags will become NUMERIC.
			}
#if 1
			else if (DefOp.is_reg(R_sp) || (DefOp.is_reg(R_bp) && UseFP)) {
				if (DebugFlag) msg("Setting reg DEF to STACKPTR\n");
				CurrDef = this->SetDefType(DefOp, STACKPTR);
				assert(CurrDef != this->Defs.GetLastRef());
				// No need to propagate; all stack and frame pointers will become STACKPTR.
			}
#endif
		}
		else if ((o_fpreg == DefOp.type) || (o_mmxreg == DefOp.type) || (o_xmmreg == DefOp.type)) {
			if (DebugFlag) msg("Setting floating point reg DEF to NUMERIC\n");
			CurrDef = this->SetDefType(DefOp, NUMERIC);
			// No need to propagate; all FP reg uses will become NUMERIC anyway.
		}
#if 0  // could these registers have pointers in them?
		else if ((o_trreg == DefOp.type) || (o_dbreg == DefOp.type) || (o_crreg == DefOp.type)) {
			if (DebugFlag) msg("Setting special reg DEF to NUMERIC\n");
			CurrDef = this->SetDefType(DefOp, NUMERIC);
		}
#endif	
		else if ((o_mem == DefOp.type) || (o_phrase == DefOp.type) || (o_displ == DefOp.type)) {
			// For memory operands, we need to identify the POINTER value that
			//  is used in the addressing mode, if possible.
			(void) this->MDFindPointerUse(DefOp, UseFP);
		}
		++CurrDef;
	} // end while all DEFs via CurrDef
	return;
} // end of SMPInstr::SetImmedTypes()

// Infer DEF, USE, and RTL SMPoperator types within the instruction based on the type
//  of operator, the type category of the instruction, and the previously known types 
//  of the operands.
bool SMPInstr::InferTypes(void) {
	bool changed = false;
	int SSANum;
	int TypeCategory = SMPTypeCategory[this->SMPcmd.itype];
	set<DefOrUse, LessDefUse>::iterator CurrDef;
	set<DefOrUse, LessDefUse>::iterator CurrUse;
	op_t DefOp = InitOp, UseOp = InitOp;
	bool DebugFlag = false;
	bool UseFP = this->BasicBlock->GetFunc()->UsesFramePointer();
	bool SafeFunc = this->BasicBlock->GetFunc()->IsSafe();
#if SMP_VERBOSE_DEBUG_INFER_TYPES
	DebugFlag |= (0 == strcmp("__libc_csu_fini", this->BasicBlock->GetFunc()->GetFuncName()));
#endif

	if (DebugFlag) {
		msg("opcode: %d TypeCategory: %d\n", this->SMPcmd.itype, TypeCategory);
	}

	// If we are already finished with all types, return false.
	if (this->TypeInferenceComplete)
		return false;

	if (this->AllDEFsTyped() && this->AllUSEsTyped()) {
		this->TypeInferenceComplete = true;
		return false;
	}

	if (this->HasDestMemoryOperand()) {
		changed |= this->MDFindPointerUse(this->MDGetMemDefOp(), UseFP);
	}
	if (this->HasSourceMemoryOperand()) {
		changed |= this->MDFindPointerUse(this->MDGetMemUseOp(), UseFP);
	}

	// The control flow instructions can be handled simply based on their type
	//  and do not need an RTL walk.
	SMPitype DFAType = this->GetDataFlowType();
	bool CallInst = ((DFAType == CALL) || (DFAType == INDIR_CALL));
	ushort IndirCallReg = R_none;
	if (DFAType == INDIR_CALL) {
		op_t TargetOp = this->GetCmd().Operands[0];
		if (TargetOp.type == o_reg)
			IndirCallReg = TargetOp.reg;
	}
	if (DebugFlag) {
		msg("DFAType: %d  CategoryInferenceComplete: %d\n",
			DFAType, this->CategoryInferenceComplete);
	}
	if ((DFAType >= JUMP) && (DFAType <= INDIR_CALL)) {
		// All USEs are either the flags (NUMERIC) or the target address (CODEPTR).
		//  The exceptions are the USE list for interrupt calls, which includes
		//  the caller-saved regs, and indirect calls through a memory
		//  operand, such as call [ebx+esi+20h], where the memory operand
		//  is a CODEPTR but the addressing registers are a BaseReg and
		//  IndexReg as in any other memory addressing, and the caller-saved
		//  regs on any call.
		CurrUse = this->GetFirstUse();
		while (CurrUse != this->GetLastUse()) {
			UseOp = CurrUse->GetOp();
			if (UseOp.is_reg(X86_FLAGS_REG))
				CurrUse = this->SetUseType(UseOp, NUMERIC);
			else if ((CurrUse->GetType() != CODEPTR)
				&& (!(this->MDIsInterruptCall() && (o_reg == UseOp.type)))
				&& (!(CallInst && MDIsCallerSavedReg(UseOp)))
				&& (!(this->HasSourceMemoryOperand() 
					&& (INDIR_CALL == this->GetDataFlowType())
					&& (o_reg == UseOp.type)))) {
				CurrUse = this->SetUseType(UseOp, CODEPTR);
			}
			else if ((CurrUse->GetType() != CODEPTR) && CallInst
				&& UseOp.is_reg(IndirCallReg)) {

				CurrUse = this->SetUseType(UseOp, CODEPTR);
			}
			++CurrUse;
		}
		this->TypeInferenceComplete = true;
		return true;
	}

	// First, see if we can infer something about DEFs and USEs just from the 
	//  type category of the instruction.
	if (!this->CategoryInferenceComplete) {
		switch (TypeCategory) {
			case 0: // no inference possible just from type category
			case 1: // no inference possible just from type category
			case 3:  // MOV instructions; inference will come from source to dest in RTL walk.
			case 5:  // binary arithmetic; inference will come in RTL walk.
			case 10:  // binary arithmetic; inference will come in RTL walk.
			case 11:  // push and pop instructions; inference will come in RTL walk.
			case 12:  // exchange instructions; inference will come in RTL walk.
				this->CategoryInferenceComplete = true;
				break;

			case 2: // Result type is always NUMERIC.
			case 7: // Result type is always NUMERIC.
			case 8: // Result type is always NUMERIC.
			case 9: // Result type is always NUMERIC.
			case 13: // Result type is always NUMERIC.
			case 14: // Result type is always NUMERIC.
			case 15: // Result type is always NUMERIC.
				CurrDef = this->GetFirstDef();
				while (CurrDef != this->GetLastDef()) {
					if (!IsEqType(NUMERIC, CurrDef->GetType())) {
						DefOp = CurrDef->GetOp();
						SSANum = CurrDef->GetSSANum();
						CurrDef = this->SetDefType(DefOp, NUMERIC);
						changed = true;
						// Be conservative and only propagate register DEFs and SAFE stack locs. We
						//  can improve this in the future. **!!**
						if ((o_reg == DefOp.type)
							|| (SafeFunc && MDIsStackAccessOpnd(DefOp, UseFP))) {
							if (this->BasicBlock->IsLocalName(DefOp)) {
								(void) this->BasicBlock->PropagateLocalDefType(DefOp, NUMERIC,
									this->GetAddr(), SSANum);
							}
							else { // global name
								this->BasicBlock->GetFunc()->ResetProcessedBlocks(); // set Processed to false
								(void) this->BasicBlock->PropagateGlobalDefType(DefOp, NUMERIC,
									SSANum);
							}
						}
					}
					++CurrDef;
				}
				this->CategoryInferenceComplete = true;
				break;

			case 4: // Unary INC, DEC, etc.: dest=source, so type remains the same
				assert(1 == this->RTL.GetCount());
				assert(this->RTL.GetRT(0)->HasRightSubTree());
				UseOp = this->RTL.GetRT(0)->GetLeftOperand(); // USE == DEF
				CurrUse = this->Uses.FindRef(UseOp);
				assert(CurrUse != this->GetLastUse());
				if (UNINIT != CurrUse->GetType()) {
					// Only one USE, and it has a type assigned, so assign that type
					// to the DEF.
					CurrDef = this->GetFirstDef();
					while (CurrDef != this->GetLastDef()) {
						// Two DEFs: EFLAGS is NUMERIC, dest==source
						DefOp = CurrDef->GetOp();
						SSANum = CurrDef->GetSSANum();
						if (DefOp.is_reg(X86_FLAGS_REG)) {
							; // SetImmedTypes already made it NUMERIC
						}
						else {
							CurrDef = this->SetDefType(DefOp, CurrUse->GetType());
							// Be conservative and only propagate register DEFs and SAFE stack locs. We
							//  can improve this in the future. **!!**
							if ((o_reg == DefOp.type)
								|| (SafeFunc && MDIsStackAccessOpnd(DefOp, UseFP))) {
								if (this->BasicBlock->IsLocalName(DefOp)) {
									(void) this->BasicBlock->PropagateLocalDefType(DefOp, CurrUse->GetType(),
										this->GetAddr(), SSANum);
								}
								else { // global name
									this->BasicBlock->GetFunc()->ResetProcessedBlocks(); // set Processed to false
									(void) this->BasicBlock->PropagateGlobalDefType(DefOp, CurrUse->GetType(),
										SSANum);
								}
							}
						}
						++CurrDef;
					}
					this->CategoryInferenceComplete = true;
					changed = true;
					this->TypeInferenceComplete = true;
				}
				break;

			case 6: // Result is always POINTER
				DefOp = this->GetFirstDef()->GetOp();
				SSANum = this->GetFirstDef()->GetSSANum();
				CurrDef = this->SetDefType(DefOp, POINTER);
				this->CategoryInferenceComplete = true;
				changed = true;
				// Be conservative and only propagate register DEFs and SAFE stack locs. We
				//  can improve this in the future. **!!**
				if ((o_reg == DefOp.type)
					|| (SafeFunc && MDIsStackAccessOpnd(DefOp, UseFP)))  {
					if (this->BasicBlock->IsLocalName(DefOp)) {
						(void) this->BasicBlock->PropagateLocalDefType(DefOp, POINTER,
							this->GetAddr(), SSANum);
					}
					else { // global name
						this->BasicBlock->GetFunc()->ResetProcessedBlocks(); // set Processed to false
						(void) this->BasicBlock->PropagateGlobalDefType(DefOp, POINTER,
							SSANum);
					}
				}
				break;

			default:
				msg("ERROR: Unknown type category for %s\n", this->GetDisasm());
				this->CategoryInferenceComplete = true;
				break;
		} // end switch on TypeCategory
	} // end if (!CategoryInference)

	// Walk the RTL and infer types based on operators and operands.
	if (DebugFlag) {
		msg("RTcount: %d\n", this->RTL.GetCount());
	}
	for (size_t index = 0; index < this->RTL.GetCount(); ++index) {
		SMPRegTransfer *CurrRT = this->RTL.GetRT(index);
		if (SMP_NULL_OPERATOR == CurrRT->GetOperator()) // nothing to infer
			continue;
		changed |= this->InferOperatorType(CurrRT);
		if (DebugFlag) {
			msg("returned from InferOperatorType\n");
		}
	} // end for all RTs in the RTL
	return changed;
} // end of SMPInstr::InferTypes()

// Infer the type of an operator within an RT based on the types of its operands and
//  based on the operator itself. Recurse down the tree if necessary.
// Return true if the operator type of the RT is updated.
bool SMPInstr::InferOperatorType(SMPRegTransfer *CurrRT) {
	bool updated = false;
	bool LeftNumeric, RightNumeric;
	bool LeftPointer, RightPointer;
	bool UseFP = this->BasicBlock->GetFunc()->UsesFramePointer();
	bool SafeFunc = this->BasicBlock->GetFunc()->IsSafe();
	set<DefOrUse, LessDefUse>::iterator CurrDef;
	set<DefOrUse, LessDefUse>::iterator CurrUse;
	set<DefOrUse, LessDefUse>::iterator LeftUse;
	set<DefOrUse, LessDefUse>::iterator RightUse;
	SMPOperandType LeftType = UNINIT;
	SMPOperandType RightType = UNINIT;
	SMPOperandType OperType = UNINIT;
	op_t UseOp = InitOp, DefOp = InitOp, LeftOp = InitOp, RightOp = InitOp;
	SMPoperator CurrOp = CurrRT->GetOperator();
	bool DebugFlag = false;
#if SMP_VERBOSE_DEBUG_INFER_TYPES
#if 0
	DebugFlag |= (0 == strcmp("strtok", this->BasicBlock->GetFunc()->GetFuncName()));
#endif
	DebugFlag = DebugFlag || ((this->address == 0x805cd52) || (this->address == 0x805cd56));
#endif

#if SMP_VERBOSE_DEBUG_INFER_TYPES
	if (DebugFlag) {
		msg("Entered InferOperatorType for CurrOp: %d\n", CurrOp);
	}
#endif
	switch (CurrOp) {
		case SMP_NULL_OPERATOR:
			break;

		case SMP_CALL:  // CALL instruction
			if (UNINIT == CurrRT->GetOperatorType()) {
				CurrRT->SetOperatorType(CODEPTR, this);
				updated = true;
				UseOp = CurrRT->GetRightOperand();
				CurrUse = this->Uses.FindRef(UseOp);
				assert(CurrUse != this->GetLastUse());
				if (UNINIT == CurrUse->GetType()) {
					CurrUse = this->SetUseType(UseOp, CODEPTR);
				}
				else if (CODEPTR != CurrUse->GetType()) {
					msg("WARNING: call target is type %d, setting to CODEPTR at %x in %s\n",
						CurrUse->GetType(), this->GetAddr(), this->GetDisasm());
					CurrUse = this->SetUseType(UseOp, CODEPTR);
				}
			}
			break;

		case SMP_INPUT:  // input from port
			if (UNINIT == CurrRT->GetOperatorType()) {
				CurrRT->SetOperatorType(UNKNOWN, this);  // Leave DEF as UNINIT and infer later
				updated = true;
			}
			break;

		case SMP_OUTPUT: // output to port
		case SMP_SIGN_EXTEND:
		case SMP_ZERO_EXTEND:
			break;

		case SMP_ADDRESS_OF: // take effective address
			if (UNINIT == CurrRT->GetOperatorType()) {
				CurrRT->SetOperatorType(POINTER, this);
				// Left operand is having its address taken, but we cannot infer what its
				//  type is.
				updated = true;
			}
			break;

		case SMP_U_LEFT_SHIFT: // unsigned left shift
		case SMP_S_LEFT_SHIFT: // signed left shift
		case SMP_U_RIGHT_SHIFT: // unsigned right shift
		case SMP_S_RIGHT_SHIFT: // signed right shift
		case SMP_ROTATE_LEFT:
		case SMP_ROTATE_LEFT_CARRY: // rotate left through carry
		case SMP_ROTATE_RIGHT:
		case SMP_ROTATE_RIGHT_CARRY: // rotate right through carry
		case SMP_U_MULTIPLY:
		case SMP_S_MULTIPLY:
		case SMP_U_DIVIDE:
		case SMP_S_DIVIDE:
		case SMP_U_REMAINDER:
		case SMP_BITWISE_NOT: // unary operator
		case SMP_BITWISE_XOR:
		case SMP_NEGATE:    // unary negation
		case SMP_S_COMPARE: // signed compare (subtraction-based)
		case SMP_U_COMPARE: // unsigned compare (AND-based)
		case SMP_LESS_THAN: // boolean test operators
		case SMP_GREATER_THAN:
		case SMP_LESS_EQUAL:
		case SMP_GREATER_EQUAL:
		case SMP_EQUAL:
		case SMP_NOT_EQUAL:
		case SMP_LOGICAL_AND:
		case SMP_LOGICAL_OR:
		case SMP_UNARY_NUMERIC_OPERATION:  // miscellaneous; produces NUMERIC result
		case SMP_BINARY_NUMERIC_OPERATION:  // miscellaneous; produces NUMERIC result
		case SMP_SYSTEM_OPERATION:   // for instructions such as CPUID, RDTSC, etc.; NUMERIC
		case SMP_UNARY_FLOATING_ARITHMETIC:  // all the same to our type system; all NUMERIC
		case SMP_BINARY_FLOATING_ARITHMETIC:  // all the same to our type system; all NUMERIC
			if (UNINIT == CurrRT->GetOperatorType()) {
				CurrRT->SetOperatorType(NUMERIC, this);
				updated = true;
			}
			// Left operand should be NUMERIC if it exists.
			UseOp = CurrRT->GetLeftOperand();
			if (UseOp.type != o_void) {
				CurrUse = this->Uses.FindRef(UseOp);
				if (CurrUse == this->GetLastUse()) {
					msg("WARNING: Adding missing USE of ");
					PrintOperand(UseOp);
					msg(" in %s\n", this->GetDisasm());
					this->Uses.SetRef(UseOp, NUMERIC, -1);
					updated = true;
				}
				else if (UNINIT == CurrUse->GetType()) {
					CurrUse = this->SetUseType(UseOp, NUMERIC);
					updated = true;
				}
			}
			// Right operand should be NUMERIC if it exists.
			if (CurrRT->HasRightSubTree()) {
				// Recurse into subtree
				updated |= this->InferOperatorType(CurrRT->GetRightTree());
			}
			else {
				UseOp = CurrRT->GetRightOperand();
				if (UseOp.type != o_void) {
					CurrUse = this->Uses.FindRef(UseOp);
					if (CurrUse == this->GetLastUse()) {
						msg("WARNING: Adding missing USE of ");
						PrintOperand(UseOp);
						msg(" in %s\n", this->GetDisasm());
						this->Uses.SetRef(UseOp, NUMERIC, -1);
						updated = true;
					}
					else if (UNINIT == CurrUse->GetType()) {
						CurrUse = this->SetUseType(UseOp, NUMERIC);
						updated = true;
					}
				}
			}
			break;

		case SMP_INCREMENT:
		case SMP_DECREMENT:
			// The type of the right operand is propagated to the operator, or vice
			//  versa, whichever receives a type first.
			assert(!CurrRT->HasRightSubTree());
			UseOp = CurrRT->GetLeftOperand();
			assert(o_void != UseOp.type);
			CurrUse = this->Uses.FindRef(UseOp);
			if (CurrUse == this->GetLastUse()) {
				msg("WARNING: Adding missing USE of ");
				PrintOperand(UseOp);
				msg(" at %x in %s\n", this->GetAddr(), this->GetDisasm());
				this->Uses.SetRef(UseOp);
				updated = true;
				break;
			}
			if (UNINIT == CurrRT->GetOperatorType()) {
				if (UNINIT != CurrUse->GetType()) {
					// Propagate operand type up to the operator.
					CurrRT->SetOperatorType(CurrUse->GetType(), this);
					updated = true;
				}
			}
			else if (UNINIT == CurrUse->GetType()) {
				// Propagate operator type to operand.
				CurrUse = this->SetUseType(UseOp, CurrRT->GetOperatorType());
				updated = true;
			}
			break;

		case SMP_ADD:
		case SMP_ADD_CARRY:   // add with carry
		case SMP_BITWISE_AND:
		case SMP_BITWISE_OR:
			// Extract the current types of right and left operands and the operator.
			LeftOp = CurrRT->GetLeftOperand();
			CurrUse = this->Uses.FindRef(LeftOp);
			assert(CurrUse != this->GetLastUse()); // found it
			LeftType = CurrUse->GetType();
			if (CurrRT->HasRightSubTree()) {
				RightType = CurrRT->GetRightTree()->GetOperatorType();
			}
			else {
				RightOp = CurrRT->GetRightOperand();
				if (o_void == RightOp.type) {
					msg("ERROR: void operand in %s\n", this->GetDisasm());
					return false;
				}
				else {
					CurrUse = this->Uses.FindRef(RightOp);
					if (CurrUse == this->GetLastUse()) {
						msg("WARNING: Adding missing USE of ");
						PrintOperand(RightOp);
						msg(" in %s\n", this->GetDisasm());
						this->Uses.SetRef(RightOp);
						updated = true;
						break;
					}