Simplify expressions explicitly using ZPULL and SPULL p-code ops. More...

#include <bitfield.hh>

Inheritance diagram for ghidra::RulePullAbsorb:

Public Member Functions
	RulePullAbsorb (const string &g)
	Constructor.

virtual Rule *	clone (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	absorbRight (Funcdata &data, PcodeOp rightOp, PcodeOp pullOp)
	Perform transforms involving the expression: `field >> #c`

int4	absorbRightAndCompZero (Funcdata &data, PcodeOp rightOp, PcodeOp andOp, PcodeOp *pullOp)
	Perform transform: `((sfield >> #n) & #1) == #0 => #0 <= sfield`

int4	absorbLeft (Funcdata &data, PcodeOp leftOp, PcodeOp pullOp)
	Perform transforms involving the expression: `field << #c`

int4	absorbLeftRight (Funcdata &data, PcodeOp rightOp, PcodeOp leftOp, PcodeOp *pullOp)
	Perform the transform: `(field << #c) >> #d => field >> (#d-#c)`

int4	absorbLeftAnd (Funcdata &data, PcodeOp andOp, PcodeOp leftOp, PcodeOp *pullOp)
	Perform the transform: `((field << #c) & #b) == #d => (field & #b>>c) == #d>>c`

int4	absorbAnd (Funcdata &data, PcodeOp andOp, PcodeOp pullOp)
	Perform transform: `field & #signbit == #0 => field < 0`

int4	absorbCompare (Funcdata &data, PcodeOp compOp, PcodeOp leftOp, PcodeOp *pullOp)
	Perform transforms involving comparisons: INT_LESS, INT_SLESS.

int4	absorbExt (Funcdata &data, PcodeOp extOp, PcodeOp pullOp)
	Perform transform: `y = SEXT( SPULL( x, #p, #n ) ) => y = SPULL( x, #p, #n )`

int4	absorbSubpiece (Funcdata &data, PcodeOp subOp, PcodeOp pullOp)
	Perform transform: `y = SUB( PULL( x, #p, #n ) ) => y = PULL( x, #p, #n )`

int4	absorbCompZero (Funcdata &data, PcodeOp compOp, PcodeOp pullOp)
	Perform transform: `ZPULL( x, #p, #1) != #0 => ZPULL(x, #p, #1)`

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 ZPULL and SPULL p-code ops.

Member Function Documentation

◆ absorbAnd()

int4 ghidra::RulePullAbsorb::absorbAnd	(	Funcdata &	data,
		PcodeOp *	andOp,
		PcodeOp *	pullOp
	)

private

Perform transform: field & #signbit == #0 => field < 0

Parameters

data	is the function
andOp	is the INT_AND op
pullOp	is the ZPULL or SPULL op

Returns: 1 if a transform was performed, 0 otherwise

References ghidra::Varnode::beginDescend(), ghidra::PcodeOp::code(), ghidra::Varnode::constantMatch(), ghidra::CPUI_INT_EQUAL, ghidra::CPUI_INT_NOTEQUAL, ghidra::CPUI_INT_SLESS, ghidra::CPUI_INT_SLESSEQUAL, ghidra::CPUI_SPULL, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::Varnode::endDescend(), ghidra::Funcdata::getArch(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::getSize(), ghidra::Varnode::getType(), ghidra::Varnode::isConstant(), ghidra::Funcdata::newConstant(), ghidra::Funcdata::opSetInput(), ghidra::Funcdata::opSetOpcode(), ghidra::TypeFactory::resizeInteger(), ghidra::Architecture::types, and ghidra::Varnode::updateType().

Referenced by applyOp().

◆ absorbCompare()

int4 ghidra::RulePullAbsorb::absorbCompare	(	Funcdata &	data,
		PcodeOp *	compOp,
		PcodeOp *	leftOp,
		PcodeOp *	pullOp
	)

private

Perform transforms involving comparisons: INT_LESS, INT_SLESS.

Perform transforms:

(boolfield << #c) s< #0 => boolfield
#0 s< (boolfield << #c) => !boolfield
(field << #c) < (#d<<#c) => field < #d
(#d<<#c) < (field << #c) => #d < field

Parameters

data	is the function
compOp	is the INT_LESS or INT_SLESS op
leftOp	is the INT_LEFT op
pullOp	is the ZPULL or SPULL op

Returns: 1 if transform performed, 0 otherwise

References ghidra::calc_mask(), ghidra::PcodeOp::code(), ghidra::CPUI_BOOL_NEGATE, ghidra::CPUI_INT_SLESS, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::getSize(), ghidra::Varnode::isConstant(), ghidra::Funcdata::newConstant(), ghidra::Funcdata::opRemoveInput(), ghidra::Funcdata::opSetInput(), ghidra::Funcdata::opSetOpcode(), and ghidra::Funcdata::totalReplace().

Referenced by absorbLeft(), and applyOp().

◆ absorbCompZero()

int4 ghidra::RulePullAbsorb::absorbCompZero	(	Funcdata &	data,
		PcodeOp *	compOp,
		PcodeOp *	pullOp
	)

private

Perform transform: ZPULL( x, #p, #1) != #0 => ZPULL(x, #p, #1)

Also transform the variant ZPULL( x, #p, #1) == #0 => !ZPULL(x, #p, #1)

Parameters

data	is the function
compOp	is the INT_EQUAL or INT_NOTEQUAL op
pullOp	is the ZPULL or SPULL op

Returns: 1 if transform performed, 0 otherwise

References ghidra::PcodeOp::code(), ghidra::Varnode::constantMatch(), ghidra::CPUI_BOOL_NEGATE, ghidra::CPUI_INT_EQUAL, ghidra::CPUI_SPULL, ghidra::Funcdata::deleteVarnode(), ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::Varnode::getAddr(), ghidra::Funcdata::getArch(), ghidra::TypeFactory::getBase(), ghidra::PcodeOp::getIn(), ghidra::Datatype::getMetatype(), ghidra::Varnode::getOffset(), ghidra::BitFieldExpression::getPullField(), ghidra::Varnode::getSize(), ghidra::Varnode::getSpace(), ghidra::Varnode::isAddrTied(), ghidra::AddrSpace::isBigEndian(), ghidra::Varnode::loneDescend(), ghidra::Funcdata::newVarnodeOut(), ghidra::Funcdata::opInsertInput(), ghidra::Funcdata::opRemoveInput(), ghidra::Funcdata::opSetInput(), ghidra::Funcdata::opSetOpcode(), ghidra::Funcdata::opUnsetOutput(), ghidra::TypeBitField::type, ghidra::TYPE_BOOL, ghidra::Architecture::types, and ghidra::Varnode::updateType().

Referenced by applyOp().

◆ absorbExt()

int4 ghidra::RulePullAbsorb::absorbExt	(	Funcdata &	data,
		PcodeOp *	extOp,
		PcodeOp *	pullOp
	)

private

Perform transform: y = SEXT( SPULL( x, #p, #n ) ) => y = SPULL( x, #p, #n )

Also transform: y = ZEXT( ZPULL( x, #p, #n ) ) => y = ZPULL( x, #p, #n )

Parameters

data	is the function
extOp	is the INT_SEXT or INT_ZEXT op
pullOp	is the ZPULL or SPULL op

Returns: 1 if transform performed, 0 otherwise

References ghidra::PcodeOp::code(), ghidra::CPUI_INT_SEXT, ghidra::CPUI_SPULL, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::PcodeOp::getIn(), ghidra::Varnode::loneDescend(), ghidra::Funcdata::opInsertInput(), ghidra::Funcdata::opSetInput(), and ghidra::Funcdata::opSetOpcode().

Referenced by applyOp().

◆ absorbLeft()

int4 ghidra::RulePullAbsorb::absorbLeft	(	Funcdata &	data,
		PcodeOp *	leftOp,
		PcodeOp *	pullOp
	)

private

Perform transforms involving the expression: field << #c

Parameters

data	is the function
leftOp	is the INT_LEFT op
pullOp	is the ZPULL or SPULL op

Returns: 1 if a transform was performed, 0 otherwise

References absorbCompare(), absorbLeftAnd(), absorbLeftRight(), ghidra::Varnode::beginDescend(), ghidra::PcodeOp::code(), ghidra::CPUI_INT_AND, ghidra::CPUI_INT_RIGHT, ghidra::CPUI_INT_SLESS, ghidra::Varnode::endDescend(), and ghidra::PcodeOp::getOut().

Referenced by applyOp().

◆ absorbLeftAnd()

int4 ghidra::RulePullAbsorb::absorbLeftAnd	(	Funcdata &	data,
		PcodeOp *	andOp,
		PcodeOp *	leftOp,
		PcodeOp *	pullOp
	)

private

Perform the transform: ((field << #c) & #b) == #d => (field & #b>>c) == #d>>c

Parameters

data	is the function
andOp	is the INT_AND op
leftOp	is the INT_LEFT op
pullOp	is the ZPULL or SPULL op

Returns: 1 if a transform was performed, 0 otherwise

References ghidra::Varnode::beginDescend(), ghidra::PcodeOp::code(), ghidra::CPUI_INT_EQUAL, ghidra::CPUI_INT_NOTEQUAL, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::Varnode::endDescend(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::getSize(), ghidra::Varnode::getType(), ghidra::Varnode::isConstant(), ghidra::Funcdata::newConstant(), ghidra::Funcdata::opSetInput(), and ghidra::Varnode::updateType().

Referenced by absorbLeft().

◆ absorbLeftRight()

int4 ghidra::RulePullAbsorb::absorbLeftRight	(	Funcdata &	data,
		PcodeOp *	rightOp,
		PcodeOp *	leftOp,
		PcodeOp *	pullOp
	)

private

Perform the transform: (field << #c) >> #d => field >> (#d-#c)

Parameters

data	is the function
rightOp	is the INT_RIGHT op
leftOp	is the INT_LEFT op
pullOp	is the ZPULL or SPULL op

Returns: 1 if a transform was performed, 0 otherwise

References ghidra::CPUI_INT_LEFT, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::getSize(), ghidra::Varnode::isConstant(), ghidra::Funcdata::newConstant(), ghidra::Funcdata::opSetInput(), ghidra::Funcdata::opSetOpcode(), and ghidra::Funcdata::totalReplace().

Referenced by absorbLeft().

◆ absorbRight()

int4 ghidra::RulePullAbsorb::absorbRight	(	Funcdata &	data,
		PcodeOp *	rightOp,
		PcodeOp *	pullOp
	)

private

Perform transforms involving the expression: field >> #c

Parameters

data	is the function
rightOp	is the INT_RIGHT or INT_SRIGHT op
pullOp	is the ZPULL or SPULL op

Returns: 1 if a transform was performed, 0 otherwise

References absorbRightAndCompZero(), ghidra::Varnode::beginDescend(), ghidra::PcodeOp::code(), ghidra::CPUI_INT_AND, ghidra::Varnode::endDescend(), and ghidra::PcodeOp::getOut().

Referenced by applyOp().

◆ absorbRightAndCompZero()

int4 ghidra::RulePullAbsorb::absorbRightAndCompZero	(	Funcdata &	data,
		PcodeOp *	rightOp,
		PcodeOp *	andOp,
		PcodeOp *	pullOp
	)

private

Perform transform: ((sfield >> #n) & #1) == #0 => #0 <= sfield

Perform the variant: ((sfield >> #n) & #1) != #0 => sfield < #0

Parameters

data	is the function
rightOp	is the INT_RIGHT or INT_SRIGHT op
andOp	is the INT_AND
pullOp	is the ZPULL or SPULL op

Returns: 1 if a transform was performed, 0 otherwise

References ghidra::Varnode::beginDescend(), ghidra::PcodeOp::code(), ghidra::Varnode::constantMatch(), ghidra::CPUI_INT_EQUAL, ghidra::CPUI_INT_LESSEQUAL, ghidra::CPUI_INT_NOTEQUAL, ghidra::CPUI_INT_SLESS, ghidra::CPUI_SPULL, ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::Varnode::endDescend(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::isConstant(), ghidra::Funcdata::opSetInput(), and ghidra::Funcdata::opSetOpcode().

Referenced by absorbRight().

◆ absorbSubpiece()

int4 ghidra::RulePullAbsorb::absorbSubpiece	(	Funcdata &	data,
		PcodeOp *	subOp,
		PcodeOp *	pullOp
	)

private

Perform transform: y = SUB( PULL( x, #p, #n ) ) => y = PULL( x, #p, #n )

Parameters

data	is the function
subOp	is the SUBPIECE op
pullOp	is the ZPULL or SPULL op

Returns: 1 if transform performed, 0 otherwise

References ghidra::PcodeOp::code(), ghidra::Funcdata::destroyVarnodeRecursive(), ghidra::PcodeOp::getIn(), ghidra::Varnode::getOffset(), ghidra::PcodeOp::getOut(), ghidra::Varnode::getSize(), ghidra::Varnode::loneDescend(), ghidra::Funcdata::opInsertInput(), ghidra::Funcdata::opSetInput(), and ghidra::Funcdata::opSetOpcode().

Referenced by applyOp().

◆ applyOp()

int4 ghidra::RulePullAbsorb::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

op	is the given PcodeOp where the Rule may apply
data	is the function to which to apply

Reimplemented from ghidra::Rule.

References absorbAnd(), absorbCompare(), absorbCompZero(), absorbExt(), absorbLeft(), absorbRight(), absorbSubpiece(), ghidra::Varnode::beginDescend(), ghidra::PcodeOp::code(), ghidra::CPUI_INT_AND, ghidra::CPUI_INT_EQUAL, ghidra::CPUI_INT_LEFT, ghidra::CPUI_INT_LESS, ghidra::CPUI_INT_NOTEQUAL, ghidra::CPUI_INT_RIGHT, ghidra::CPUI_INT_SEXT, ghidra::CPUI_INT_SLESS, ghidra::CPUI_INT_SRIGHT, ghidra::CPUI_INT_ZEXT, ghidra::CPUI_SUBPIECE, ghidra::Varnode::endDescend(), and ghidra::PcodeOp::getOut().

◆ clone()

virtual Rule * ghidra::RulePullAbsorb::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

grouplist is 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::RulePullAbsorb::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

oplist is the array to populate

Reimplemented from ghidra::Rule.

References ghidra::CPUI_SPULL, and ghidra::CPUI_ZPULL.

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

bitfield.hh
bitfield.cc

Public Member Functions

Private Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ absorbAnd()

◆ absorbCompare()

◆ absorbCompZero()

◆ absorbExt()

◆ absorbLeft()

◆ absorbLeftAnd()

◆ absorbLeftRight()

◆ absorbRight()

◆ absorbRightAndCompZero()

◆ absorbSubpiece()

◆ applyOp()

◆ clone()

◆ getOpList()