ghidra::DisassemblyCache Class Reference

A container for disassembly context used by the SLEIGH engine. More...

#include <sleigh.hh>

Public Member Functions
	DisassemblyCache (Translate *trans, ContextCache *ccache, AddrSpace *cspace, int4 cachesize, int4 windowsize)
	Constructor. More...
	~DisassemblyCache (void)
	Destructor.
ParserContext *	getParserContext (const Address &addr)
	Get the parser for a particular Address. More...

Private Member Functions
void	initialize (int4 min, int4 hashsize)
	Initialize the hash-table of ParserContexts. More...
void	free (void)
	Free the hash-table of ParserContexts.

Private Attributes
Translate *	translate
	The Translate object that owns this cache.
ContextCache *	contextcache
	Cached values from the ContextDatabase.
AddrSpace *	constspace
	The constant address space.
int4	minimumreuse
	Can call getParserContext this many times, before a ParserContext is reused.
uint4	mask
	Size of the hashtable in form 2^n-1.
ParserContext **	list
	(circular) array of currently cached ParserContext objects
int4	nextfree
	Current end/beginning of circular list.
ParserContext **	hashtable
	Hashtable for looking up ParserContext via Address.

Detailed Description

A container for disassembly context used by the SLEIGH engine.

This acts as a factor for the ParserContext objects which are used to disassemble a single instruction. These all share a ContextCache which is a front end for accessing the ContextDatabase and resolving context variables from the SLEIGH spec. ParserContext objects are stored in a hash-table keyed by the address of the instruction.

Constructor & Destructor Documentation

DisassemblyCache()

ghidra::DisassemblyCache::DisassemblyCache	(	Translate *	trans,
		ContextCache *	ccache,
		AddrSpace *	cspace,
		int4	cachesize,
		int4	windowsize
	)

Constructor.

Parameters

trans	is the Translate object instantiating this cache (for inst_next2 callbacks)
ccache	is the ContextCache front-end shared across all the parser contexts
cspace	is the constant address space used for minting constant Varnodes
cachesize	is the number of distinct ParserContext objects in this cache
windowsize	is the size of the ParserContext hash-table

Member Function Documentation

getParserContext()

ParserContext * ghidra::DisassemblyCache::getParserContext

(

const Address &

addr

)

Get the parser for a particular Address.

Return a (possibly cached) ParserContext that is associated with addr If n different calls to this interface are made with n different Addresses, if

• n <= minimumreuse AND
• all the addresses are within the windowsize (=mask+1)

then the cacher guarantees that you get all different ParserContext objects

Parameters

addr	is the Address to disassemble at

Returns

the ParserContext associated with the address

References ghidra::Address::getOffset().

Referenced by ghidra::Sleigh::obtainContext(), and ghidra::SleighBuilder::SleighBuilder().

initialize()

void ghidra::DisassemblyCache::initialize ( int4  min, int4  hashsize  )

private

Initialize the hash-table of ParserContexts.

Parameters

min	is the minimum number of allocations before a reuse is expected
hashsize	is the number of elements in the hash-table

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

• sleigh.hh
• sleigh.cc