LoadGuard Class Reference

Description of a LOAD operation that needs to be guarded. More...

#include <heritage.hh>

Public Member Functions
bool	isGuarded (const Address &addr) const
	Does this guard apply to the given address. More...

Private Member Functions
void	establishRange (const ValueSetRead &valueSet)
	Convert partial value set analysis into guard range. More...
void	finalizeRange (const ValueSetRead &valueSet)
	Convert value set analysis to final guard range.
void	set (PcodeOp *o, AddrSpace *s, uintb off)
	Set a new unanalyzed LOAD guard that initially guards everything. More...

Private Attributes
PcodeOp *	op
	The LOAD op.
AddrSpace *	spc
	The stack space being loaded from.
uintb	pointerBase
	Base offset of the pointer.
uintb	minimumOffset
	Minimum offset of the LOAD.
uintb	maximumOffset
	Maximum offset of the LOAD.
int4	step
	Step of any access into this range (0=unknown)
int4	analysisState
	0=unanalyzed, 1=analyzed(partial result), 2=analyzed(full result)

Friends
class	Heritage

Detailed Description

Description of a LOAD operation that needs to be guarded.

Heritage maintains a list of CPUI_LOAD ops that reference the stack dynamically. These can potentially alias stack Varnodes, so we maintain what (possibly limited) information we known about the range of stack addresses that can be referenced.

Member Function Documentation

establishRange()

void LoadGuard::establishRange ( const ValueSetRead &  valueSet )

private

Convert partial value set analysis into guard range.

Make some determination of the range of possible values for a LOAD based an partial value set analysis. This can sometimes get

• minimumOffset - otherwise the original constant pulled with the LOAD is used
• step - the partial analysis shows step and direction
• maximumOffset - in rare cases

isAnalyzed is set to true, if full range analysis is not needed

Parameters

valueSet

is the calculated value set as seen by the LOAD operation

References analysisState, AddrSpace::getHighest(), CircleRange::getSize(), maximumOffset, minimumOffset, pointerBase, spc, and step.

isGuarded()

bool LoadGuard::isGuarded

(

const Address &

addr

)

const

Does this guard apply to the given address.

Check if the address falls within the range defined by this

Parameters

addr	is the given address

Returns

true if the address is contained

References Address::getOffset(), Address::getSpace(), maximumOffset, minimumOffset, and spc.

Referenced by RuleIndirectCollapse::applyOp().

set()

void LoadGuard::set ( PcodeOp *  o, AddrSpace *  s, uintb  off  )

inlineprivate

Set a new unanalyzed LOAD guard that initially guards everything.

Parameters

o	is the LOAD op
s	is the (stack) space it is loading from
off	is the base offset that is indexed from

References analysisState, AddrSpace::getHighest(), maximumOffset, minimumOffset, op, pointerBase, spc, and step.

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The documentation for this class was generated from the following files:

• heritage.hh
• heritage.cc