decompiler 1.0.0
Public Member Functions | Private Member Functions | Static Private Member Functions | List of all members
ghidra::RuleInsertAbsorb Class Reference

Simplify expressions explicitly using the INSERT p-code op. More...

#include <bitfield.hh>

Inheritance diagram for ghidra::RuleInsertAbsorb:
ghidra::Rule

Public Member Functions

 RuleInsertAbsorb (const string &g)
 Constructor.
 
virtual Ruleclone (const ActionGroupList &grouplist) const
 Clone the Rule.
 
virtual void getOpList (vector< uint4 > &oplist) const
 List of op codes this rule operates on.
 
virtual int4 applyOp (PcodeOp *op, Funcdata &data)
 Attempt to apply this Rule.
 
- Public Member Functions inherited from ghidra::Rule
 Rule (const string &g, uint4 fl, const string &nm)
 Construct given group, properties name.
 
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.
 
uint4 getBreakPoint (void) const
 Return breakpoint toggles.
 
virtual void reset (Funcdata &data)
 Reset this Rule.
 
virtual void resetStats (void)
 Reset Rule statistics.
 
virtual void printStatistics (ostream &s) const
 Print statistics for this Rule.
 

Private Member Functions

int4 absorbAnd (Funcdata &data, PcodeOp *andOp, PcodeOp *insertOp)
 Perform the transform: INSERT( x & #mask, #p, #n ) => INSERT( x, #p, #n )
 
int4 absorbRightLeft (Funcdata &data, PcodeOp *nextOp, PcodeOp *rightOp, PcodeOp *insertOp)
 Perform the transform: INSERT( (x << #c) >> #c, #p, #n ) => INSERT(x, #p, #n )
 
int4 absorbShiftAdd (Funcdata &data, PcodeOp *rightOp, PcodeOp *addOp, PcodeOp *insertOp)
 Perform the transform: field = (a * #c + b * #c) >> #n => field = a + b
 
int4 absorbNestedAnd (Funcdata &data, PcodeOp *baseOp, PcodeOp *insertOp)
 Perform transforms like: INSERT( (x & #0xff) + y ) => INSERT( x + y )
 

Static Private Member Functions

static VarnodeleftShiftVarnode (Varnode *vn, int4 sa)
 Test if a Varnode is left-shifted by the given amount.
 

Additional Inherited Members

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

Detailed Description

Simplify expressions explicitly using the INSERT p-code op.

Member Function Documentation

◆ absorbAnd()

int4 ghidra::RuleInsertAbsorb::absorbAnd ( Funcdata data,
PcodeOp andOp,
PcodeOp insertOp 
)
private

Perform the transform: INSERT( x & #mask, #p, #n ) => INSERT( x, #p, #n )

Parameters
datais the function
andOpis the INT_AND op
insertOpis the INSERT op
Returns
1 if transform performed, 0 otherwise

References ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::PcodeOp::getIn(), ghidra::InsertExpression::getLSBMask(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::isConstant(), and ghidra::Funcdata::opSetInput().

Referenced by applyOp().

◆ absorbNestedAnd()

int4 ghidra::RuleInsertAbsorb::absorbNestedAnd ( Funcdata data,
PcodeOp baseOp,
PcodeOp insertOp 
)
private

Perform transforms like: INSERT( (x & #0xff) + y ) => INSERT( x + y )

The op feeding the INSERT can be any operation where more significant bits of the input do not affect the less significant bits.

Parameters
datais the function
baseOpis one of INT_ADD, INT_AND, INT_OR, or INT_XOR.
insertOpis the INSERT op
Returns
1 if transform performed, 0 otherwise

References ghidra::PcodeOp::code(), ghidra::CPUI_INT_AND, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::Varnode::getDef(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::isConstant(), ghidra::Varnode::isWritten(), ghidra::Varnode::loneDescend(), and ghidra::Funcdata::opSetInput().

Referenced by applyOp().

◆ absorbRightLeft()

int4 ghidra::RuleInsertAbsorb::absorbRightLeft ( Funcdata data,
PcodeOp nextOp,
PcodeOp rightOp,
PcodeOp insertOp 
)
private

Perform the transform: INSERT( (x << #c) >> #c, #p, #n ) => INSERT(x, #p, #n )

Also transform the variant: INSERT( SUB( x << #c, #0) >> #c, #p, #n ) => INSERT(x, #p, #n)

References ghidra::PcodeOp::code(), ghidra::CPUI_INT_LEFT, ghidra::CPUI_SUBPIECE, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::Varnode::getDef(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::getSize(), ghidra::Varnode::isConstant(), ghidra::Varnode::isWritten(), and ghidra::Funcdata::opSetInput().

Referenced by applyOp().

◆ absorbShiftAdd()

int4 ghidra::RuleInsertAbsorb::absorbShiftAdd ( Funcdata data,
PcodeOp rightOp,
PcodeOp addOp,
PcodeOp insertOp 
)
private

Perform the transform: field = (a * #c + b * #c) >> #n => field = a + b

Parameters
datais the function
rightOpis the INT_RIGHT or INT_SRIGHT op
addOpis the INT_ADD op
insertOpis the INSERT op
Returns
1 if transform performed, 0 otherwise

References ghidra::CPUI_INT_ADD, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::getSize(), ghidra::Varnode::getType(), ghidra::Varnode::isConstant(), leftShiftVarnode(), ghidra::Funcdata::newConstant(), ghidra::Funcdata::opSetInput(), ghidra::Funcdata::opSetOpcode(), and ghidra::Varnode::updateType().

Referenced by applyOp().

◆ applyOp()

int4 ghidra::RuleInsertAbsorb::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 ghidra::Rule.

References absorbAnd(), absorbNestedAnd(), absorbRightLeft(), absorbShiftAdd(), ghidra::PcodeOp::code(), ghidra::CPUI_INT_ADD, ghidra::CPUI_INT_AND, ghidra::CPUI_INT_LEFT, ghidra::CPUI_INT_MULT, ghidra::CPUI_INT_OR, ghidra::CPUI_INT_RIGHT, ghidra::CPUI_INT_SRIGHT, ghidra::CPUI_INT_XOR, ghidra::CPUI_SUBPIECE, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::Varnode::getDef(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::Varnode::isConstant(), ghidra::Varnode::isWritten(), and ghidra::Funcdata::opSetInput().

◆ clone()

virtual Rule * ghidra::RuleInsertAbsorb::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 ghidra::Rule.

References ghidra::ActionGroupList::contains(), and ghidra::Rule::getGroup().

◆ getOpList()

void ghidra::RuleInsertAbsorb::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 ghidra::Rule.

References ghidra::CPUI_INSERT.

◆ leftShiftVarnode()

Varnode * ghidra::RuleInsertAbsorb::leftShiftVarnode ( Varnode vn,
int4  sa 
)
staticprivate

Test if a Varnode is left-shifted by the given amount.

If the Varnode is shifted, return the Varnode stripped of the shift.

Parameters
vnis the Varnode to test
sais the given shift amount
Returns
the stripped Varnode or null

References ghidra::PcodeOp::code(), ghidra::CPUI_INT_LEFT, ghidra::CPUI_INT_MULT, ghidra::Varnode::getDef(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::Varnode::isConstant(), and ghidra::Varnode::isWritten().

Referenced by absorbShiftAdd().


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