decompiler  1.0.0
Public Member Functions | Static Private Member Functions | List of all members
RulePtrArith Class Reference

Transform pointer arithmetic. More...

Inheritance diagram for RulePtrArith:
Rule

Public Member Functions

 RulePtrArith (const string &g)
 Constructor.
 
virtual Ruleclone (const ActionGroupList &grouplist) const
 Clone the Rule. More...
 
virtual void getOpList (vector< uint4 > &oplist) const
 List of op codes this rule operates on. More...
 
virtual int4 applyOp (PcodeOp *op, Funcdata &data)
 Attempt to apply this Rule. More...
 
- Public Member Functions inherited from Rule
 Rule (const string &g, uint4 fl, const string &nm)
 Construct given group, properties name. More...
 
virtual ~Rule (void)
 Destructor.
 
const string & getName (void) const
 Return the name of this Rule.
 
const string & getGroup (void) const
 Return the group this Rule belongs to.
 
uint4 getNumTests (void)
 Get number of attempted applications.
 
uint4 getNumApply (void)
 Get number of successful applications.
 
void setBreak (uint4 tp)
 Set a breakpoint on this Rule.
 
void clearBreak (uint4 tp)
 Clear a breakpoint on this Rule.
 
void clearBreakPoints (void)
 Clear all breakpoints on this Rule.
 
void turnOnWarnings (void)
 Enable warnings for this Rule.
 
void turnOffWarnings (void)
 Disable warnings for this Rule.
 
bool isDisabled (void) const
 Return true if this Rule is disabled.
 
void setDisable (void)
 Disable this Rule (within its pool)
 
void clearDisable (void)
 Enable this Rule (within its pool)
 
bool checkActionBreak (void)
 Check if an action breakpoint is turned on. More...
 
uint4 getBreakPoint (void) const
 Return breakpoint toggles.
 
virtual void reset (Funcdata &data)
 Reset this Rule. More...
 
virtual void resetStats (void)
 Reset Rule statistics. More...
 
virtual void printStatistics (ostream &s) const
 Print statistics for this Rule. More...
 

Static Private Member Functions

static bool verifyAddTreeBottom (PcodeOp *op, int4 slot)
 Verify that given PcodeOp occurs at the bottom of the CPUI_INT_ADD tree. More...
 

Additional Inherited Members

- Public Types inherited from Rule
enum  typeflags { type_disable = 1, rule_debug = 2, warnings_on = 4, warnings_given = 8 }
 Properties associated with a Rule. More...
 

Detailed Description

Transform pointer arithmetic.

Rule for converting integer arithmetic to pointer arithmetic. A string of INT_ADDs is converted into PTRADDs and PTRSUBs.

Basic algorithm: Starting with a varnode of known pointer type (with known size):

We need to be wary of most things being in the units of the space being pointed at. Type calculations are always in bytes so we need to convert between space units and bytes.

Member Function Documentation

int4 RulePtrArith::applyOp ( PcodeOp op,
Funcdata data 
)
virtual

Attempt to apply this Rule.

This method contains the main logic for applying the Rule. It must use a given PcodeOp as the point at which the Rule applies. If it does apply, changes are made directly to the function and 1 (non-zero) is returned, otherwise 0 is returned.

Parameters
opis the given PcodeOp where the Rule may apply
datais the function to which to apply

Reimplemented from Rule.

References AddrSpace::addressToByteInt(), AddTreeState::apply(), CPUI_PTRADD, AddTreeState::ct, PcodeOp::getIn(), Datatype::getMetatype(), TypePointer::getPtrTo(), Datatype::getSize(), Varnode::getType(), TypePointer::getWordSize(), Funcdata::isTypeRecoveryOn(), Funcdata::newConstant(), PcodeOp::numInput(), Funcdata::opSetAllInput(), Funcdata::opSetOpcode(), and TYPE_PTR.

virtual Rule* RulePtrArith::clone ( const ActionGroupList grouplist) const
inlinevirtual

Clone the Rule.

If this Rule is a member of one of the groups in the grouplist, this returns a clone of the Rule, otherwise NULL is returned.

Parameters
grouplistis the list of groups being cloned
Returns
the cloned Rule or NULL

Implements Rule.

References ActionGroupList::contains(), and AddTreeState::data.

void RulePtrArith::getOpList ( vector< uint4 > &  oplist) const
virtual

List of op codes this rule operates on.

Populate the given array with all possible OpCodes this Rule might apply to. By default, this method returns all possible OpCodes

Parameters
oplistis the array to populate

Reimplemented from Rule.

References CPUI_INT_ADD.

bool RulePtrArith::verifyAddTreeBottom ( PcodeOp op,
int4  slot 
)
staticprivate

Verify that given PcodeOp occurs at the bottom of the CPUI_INT_ADD tree.

The main RulePtrArith algorithm assumes that the pointer Varnode is at the bottom of the expression tree that is adding an offset to the pointer. This routine verifies this condition.

Parameters
opis the given PcodeOp which is the putative last operation in the tree
slotis the slot of the pointer Varnode within the given PcodeOp
Returns
true if the pointer is at the bottom of the tree, false otherwise

References Varnode::beginDescend(), PcodeOp::code(), CPUI_INT_ADD, CPUI_LOAD, CPUI_STORE, Varnode::endDescend(), PcodeOp::getIn(), PcodeOp::getOut(), Varnode::isConstant(), Varnode::isInput(), and Varnode::isSpacebase().


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