expression.hh File Reference

Classes to collect, analyze, and match expressions within p-code data-flow. More...

#include "op.hh"

Classes
struct	ghidra::PcodeOpNode
	An edge in a data-flow path or graph. More...
struct	ghidra::TraverseNode
	Node for a forward traversal of a Varnode expression. More...
class	ghidra::BooleanMatch
	Static methods for determining if two boolean expressions are the same or complementary. More...
class	ghidra::BooleanExpressionMatch
	A helper class for describing the similarity of the boolean condition between 2 CBRANCH operations. More...
class	ghidra::AdditiveEdge
	Class representing a term in an additive expression. More...
class	ghidra::TermOrder
	A class for ordering Varnode terms in an additive expression. More...
class	ghidra::AddExpression
	Class for lightweight matching of two additive expressions. More...
class	ghidra::AddExpression::Term
	A term in the expression. More...

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

Detailed Description

Classes to collect, analyze, and match expressions within p-code data-flow.

Function Documentation

functionalDifference()

bool ghidra::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

functionalEquality()

bool ghidra::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

functionalEqualityLevel()

int4 ghidra::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