op.hh File Reference

The PcodeOp and PcodeOpBank classes. More...

#include "typeop.hh"

Classes
class	IopSpace
	Space for storing internal PcodeOp pointers as addresses. More...
class	PcodeOp
	Lowest level operation of the p-code language. More...
class	PcodeOpBank
	Container class for PcodeOps associated with a single function. More...

Typedefs
typedef map< SeqNum, PcodeOp * >	PcodeOpTree
	A map from sequence number (SeqNum) to PcodeOp.

Functions
int4	functionalEqualityLevel (Varnode *vn1, Varnode *vn2, Varnode **res1, Varnode **res2)
	Try to determine if vn1 and vn2 contain the same value. More...
bool	functionalEquality (Varnode *vn1, Varnode *vn2)
	Determine if two Varnodes hold the same value. More...
bool	functionalDifference (Varnode *vn1, Varnode *vn2, int4 depth)
	Return true if vn1 and vn2 are verifiably different values. More...

Detailed Description

The PcodeOp and PcodeOpBank classes.

Function Documentation

bool functionalDifference	(	Varnode *	vn1,
		Varnode *	vn2,
		int4	depth
	)

Return true if vn1 and vn2 are verifiably different values.

This is actually a rather speculative test

Parameters

vn1	is the first Varnode to compare
vn2	is the second Varnode
depth	is the maximum level to recurse while testing

Returns

true if they are different

References PcodeOp::code(), Varnode::getAddr(), Varnode::getDef(), PcodeOp::getIn(), Varnode::isConstant(), Varnode::isFree(), Varnode::isInput(), Varnode::isWritten(), and PcodeOp::numInput().

Referenced by PcodeOpBank::endDead().

bool functionalEquality	(	Varnode *	vn1,
		Varnode *	vn2
	)

Determine if two Varnodes hold the same value.

Only return true if it can be immediately determined they are equivalent

Parameters

vn1	is the first Varnode
vn2	is the second Varnode

Returns

true if they are provably equal

References functionalEqualityLevel().

Referenced by RuleEquality::applyOp(), RuleRangeMeld::applyOp(), RuleMultiCollapse::applyOp(), RuleSborrow::applyOp(), PcodeOpBank::endDead(), and ActionMarkImplied::isPossibleAlias().

int4 functionalEqualityLevel	(	Varnode *	vn1,
		Varnode *	vn2,
		Varnode **	res1,
		Varnode **	res2
	)

Try to determine if vn1 and vn2 contain the same value.

Return:

• -1, if they do not, or if it can't be immediately verified
• 0, if they do hold the same value
• >0, if the result is contingent on additional varnode pairs having the same value In the last case, the varnode pairs are returned as (res1[i],res2[i]), where the return value is the number of pairs.

  Parameters

  vn1	is the first Varnode to compare
  vn2	is the second Varnode
  res1	is a reference to the first returned Varnode
  res2	is a reference to the second returned Varnode

  Returns

  the result of the comparison

References PcodeOp::code(), CPUI_LOAD, CPUI_PTRADD, PcodeOp::getAddr(), Varnode::getDef(), PcodeOp::getIn(), Varnode::getOffset(), PcodeOp::isCall(), PcodeOp::isCommutative(), PcodeOp::isMarker(), and PcodeOp::numInput().

Referenced by RulePushMulti::applyOp(), cseFindInBlock(), PcodeOpBank::endDead(), ConditionalJoin::findDups(), ActionMultiCse::findMatch(), RulePushMulti::findSubstitute(), and functionalEquality().