Package ghidra.app.plugin.assembler.sleigh.expr

Class OperandValueSolver

java.lang.Object

ghidra.app.plugin.assembler.sleigh.expr.AbstractExpressionSolver<OperandValue>

ghidra.app.plugin.assembler.sleigh.expr.OperandValueSolver

public class OperandValueSolver
extends AbstractExpressionSolver<OperandValue>

Solves expressions of an operand value

These are a sort of named sub-expression, but they may also specify a shift in encoding.

Field Summary

Fields inherited from class ghidra.app.plugin.assembler.sleigh.expr.AbstractExpressionSolver

dbg, solver

Constructor Summary

Constructors

Constructor	Description
OperandValueSolver()

Method Summary

Modifier and Type	Method	Description
static PatternExpression	getDefiningExpression(OperandSymbol sym)	Obtains the "defining expression"
int	getInstructionLength(OperandValue ov)	Determines the length of the subconstructor that would be returned had the expression not depended on an undefined symbol.
MaskedLong	getValue(OperandValue ov, Map<String,Long> vals, AssemblyResolvedPatterns cur)	Attempt to get a constant value for the expression
AssemblyResolution	solve(AbstractAssemblyResolutionFactory<?,?> factory, OperandValue ov, MaskedLong goal, Map<String,Long> vals, AssemblyResolvedPatterns cur, Set<SolverHint> hints, String description)	Attempt to solve an expression for a given value
MaskedLong	valueForResolution(OperandValue ov, Map<String,Long> vals, AssemblyResolvedPatterns rc)	Compute the value of the expression given the (possibly-intermediate) resolution

Methods inherited from class ghidra.app.plugin.assembler.sleigh.expr.AbstractExpressionSolver

register

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

OperandValueSolver

public OperandValueSolver()

Method Details

getDefiningExpression

public static PatternExpression getDefiningExpression(OperandSymbol sym)

Obtains the "defining expression"

This is either the symbol's assigned defining expression, or the expression associated with its defining symbol.

Returns:

the defining expression, or null if neither is available

solve

public AssemblyResolution solve(AbstractAssemblyResolutionFactory<?,?> factory,
 OperandValue ov,
 MaskedLong goal,
 Map<String,Long> vals,
 AssemblyResolvedPatterns cur,
 Set<SolverHint> hints,
 String description)
                         throws NeedsBackfillException

Description copied from class: AbstractExpressionSolver

Attempt to solve an expression for a given value

Specified by:

solve in class AbstractExpressionSolver<OperandValue>

ov - the expression to solve

goal - the desired value of the expression

vals - values of defined symbols

hints - describes techniques applied by calling solvers

description - the description to give to resolved solutions

Returns:

the resolution

Throws:

NeedsBackfillException - if the expression refers to an undefined symbol

getValue

public MaskedLong getValue(OperandValue ov,
 Map<String,Long> vals,
 AssemblyResolvedPatterns cur)
                    throws NeedsBackfillException

Description copied from class: AbstractExpressionSolver

Attempt to get a constant value for the expression

Specified by:

getValue in class AbstractExpressionSolver<OperandValue>

Parameters:

ov - the expression

vals - values of defined symbols

Returns:

the constant value, or null if it depends on a variable

Throws:

NeedsBackfillException - if the expression refers to an undefined symbol

getInstructionLength

public int getInstructionLength(OperandValue ov)

Description copied from class: AbstractExpressionSolver

Determines the length of the subconstructor that would be returned had the expression not depended on an undefined symbol.

This is used by the backfilling process to ensure values are written to the correct offset

Specified by:

getInstructionLength in class AbstractExpressionSolver<OperandValue>

Parameters:

ov - the expression

Returns:

the length of filled in token field(s).

valueForResolution

public MaskedLong valueForResolution(OperandValue ov,
 Map<String,Long> vals,
 AssemblyResolvedPatterns rc)

Description copied from class: AbstractExpressionSolver

Compute the value of the expression given the (possibly-intermediate) resolution

Specified by:

valueForResolution in class AbstractExpressionSolver<OperandValue>

Parameters:

ov - the expression to evaluate

vals - values of defined symbols

rc - the resolution on which to evaluate it

Returns:

the result