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livenessAnalyzer Class Reference

Liveness analyzer. More...

#include <liveness.h>

Inheritance diagram for livenessAnalyzer::

Public Methods
	livenessAnalyzer (bool debug)
	Create a liveness analysis object. More...
virtual string	name ()
	Name of the analysis. More...
void	clear ()
	Reset liveness information. More...
bool	isLive (stmtNode *stmt)
	Is a particular statement live. More...
virtual void	at_index (stmtLocation current, binaryNode binary, pointerValue &left, pointerValue &right, pointerValue &result, bool result_is_a_use)
virtual void	at_call (stmtLocation current, callNode call, pointerValue &call_target, procNode *callee, pointervalue_list &arguments, pointerValue &return_val)
virtual void	at_heap (stmtLocation current, callNode call, pointervalue_list &arguments, pointerValue &return_val, bool is_alloc)
virtual void	at_assignment (stmtLocation current, binaryNode binary, pointerValue &left, pointerValue &right, pointerValue &result, bool result_is_a_use, memoryblock_set &changes)
virtual void	at_return (stmtLocation stmt, returnNode ret, pointerValue &result, pointerValue &return_val)
virtual void	at_exprstmt (stmtLocation stmt, exprstmtNode es, pointerValue &result)
virtual void	at_if (stmtLocation stmt, ifNode ifnode, pointerValue &result)
virtual void	at_merge (basicblockLocation where, memoryBlock block, memoryuse_list &phi_uses, pointerValue &result, memoryblock_set &changes)
virtual void	at_stmt_exit (stmtLocation *stmt, pointerValue &result)
virtual void	at_basicblock_entry (basicblockLocation block, procedureInfo info, pointerValue &initial)
virtual void	at_procedure_entry (procLocation proc, procedureInfo info, pointerValue &return_val)
virtual void	at_procedure_exit (procLocation proc, procedureInfo info, pointerValue &return_val)
Protected Methods
void	collectDefs (pointerValue &pointer)
	Collect defs. More...
void	addDef (memoryDef *def)
	Add one def. More...
bool	determineLiveness ()
	Determine liveness. More...
bool	isLive (memoryUse use, memoryBlock owner)
	Look up liveness. More...
void	setLive (stmtLocation *where)
	Set live for statements. More...
void	setLive (basicblockLocation where, memoryBlock block)
	Set live for merge-points. More...
Private Types
typedef set< stmtNode * >	stmt_liveness_set
typedef stmt_liveness_set::iterator	stmt_liveness_set_p
typedef set< stmtLocation * >	stmtlocation_liveness_set
typedef stmtlocation_liveness_set::iterator	stmtlocation_liveness_set_p
typedef pair< basicblockLocation , memoryBlock >	mergepoint_pair
typedef set< mergepoint_pair >	mergepoint_liveness_set
typedef mergepoint_liveness_set::iterator	mergepoint_liveness_set_p
typedef list< bool >	change_stack
Private Attributes
stmt_liveness_set	_live_stmts
	Live statements. More...
stmtlocation_liveness_set	_live_stmtlocations
	Live statement locations. More...
mergepoint_liveness_set	_live_mergepoints
	Live merge points. More...
memorydef_set	_defs
	Collect defs. More...
bool	_change
	Record changes. More...
change_stack	_change_stack
	Change stack. More...
bool	_debug
	Debug flag. More...

Detailed Description

Liveness analyzer.

Liveness is a property of statements in the program. A statement is live if any of the defs created by the statement are live. A def is live if it has uses, and at least one of it's uses is live. A use is live if the statement in which it occurs is live.

Member Typedef Documentation

typedef list< bool > livenessAnalyzer::change_stack [private]

typedef set< mergepoint_pair > livenessAnalyzer::mergepoint_liveness_set [private]

typedef mergepoint_liveness_set::iterator livenessAnalyzer::mergepoint_liveness_set_p [private]

typedef pair< basicblockLocation *, memoryBlock * > livenessAnalyzer::mergepoint_pair [private]

typedef set< stmtNode * > livenessAnalyzer::stmt_liveness_set [private]

typedef stmt_liveness_set::iterator livenessAnalyzer::stmt_liveness_set_p [private]

typedef set< stmtLocation * > livenessAnalyzer::stmtlocation_liveness_set [private]

typedef stmtlocation_liveness_set::iterator livenessAnalyzer::stmtlocation_liveness_set_p [private]

Constructor & Destructor Documentation

livenessAnalyzer::livenessAnalyzer ( bool debug )

Create a liveness analysis object.

Member Function Documentation

void livenessAnalyzer::addDef ( memoryDef * def ) [protected]

Add one def.

void livenessAnalyzer::at_assignment ( stmtLocation * current,

binaryNode * binary,

pointerValue & left,

pointerValue & right,

pointerValue & result,

bool result_is_a_use,

memoryblock_set & changes

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_basicblock_entry ( basicblockLocation * blockloc,

procedureInfo * info,

pointerValue & initial

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_call ( stmtLocation * current,

callNode * call,

pointerValue & call_target,

procNode * callee,

pointervalue_list & arguments,

pointerValue & return_val

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_exprstmt ( stmtLocation * stmt,

exprstmtNode * es,

pointerValue & result

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_heap ( stmtLocation * current,

callNode * call,

pointervalue_list & arguments,

pointerValue & return_val,

bool is_alloc

) [virtual]

void livenessAnalyzer::at_if ( stmtLocation * stmt,

ifNode * ifnode,

pointerValue & result

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_index ( stmtLocation * current,

binaryNode * binary,

pointerValue & left,

pointerValue & right,

pointerValue & result,

bool result_is_a_use

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_merge ( basicblockLocation * where,

memoryBlock * block,

memoryuse_list & phi_uses,

pointerValue & result,

memoryblock_set & changes

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_procedure_entry ( procLocation * proc,

procedureInfo * info,

pointerValue & return_val

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_procedure_exit ( procLocation * proc,

procedureInfo * info,

pointerValue & return_val

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_return ( stmtLocation * stmt,

returnNode * ret,

pointerValue & result,

pointerValue & return_val

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::at_stmt_exit ( stmtLocation * stmt,

pointerValue & result

) [virtual]

Reimplemented from analysisProblem.

void livenessAnalyzer::clear ( )

Reset liveness information.
Allow the liveness analyzer to be run again.

void livenessAnalyzer::collectDefs ( pointerValue & pointer ) [protected]

Collect defs.

bool livenessAnalyzer::determineLiveness ( ) [protected]

Determine liveness.
Given the set of defs collected earlier, visit each def and each use that it reaches to see if any of them are live.

bool livenessAnalyzer::isLive ( memoryUse * use,

memoryBlock * owner

) [protected]

Look up liveness.
Look up the liveness of a memoryUse. This depends on the kind of location it comes from. As a special case, procLocations are always considered live.

bool livenessAnalyzer::isLive ( stmtNode * stmt )

Is a particular statement live.
This is the context insensitive query

virtual string livenessAnalyzer::name ( ) [inline, virtual]

Name of the analysis.
Just for debug purposes.
Reimplemented from analysisProblem.

void livenessAnalyzer::setLive ( basicblockLocation * where,

memoryBlock * block

) [protected]

Set live for merge-points.
Record the given merge-point as live. Since all blocks share a single merge-point location, we need to distinguish which ones are live by the specific block being merged.

void livenessAnalyzer::setLive ( stmtLocation * stmt_loc ) [protected]

Set live for statements.
Record the given statement location as live.

Member Data Documentation

bool livenessAnalyzer::_change [private]

Record changes.

change_stack livenessAnalyzer::_change_stack [private]

Change stack.
We need to record the state of the change boolean in procedures above the current one.

bool livenessAnalyzer::_debug [private]

Debug flag.

memorydef_set livenessAnalyzer::_defs [private]

Collect defs.
This set is used on a per-statement basis to collect memoryDef objects. Once we have the set of defs, we can decide whether or not the current statement is live.

mergepoint_liveness_set livenessAnalyzer::_live_mergepoints [private]

Live merge points.
This set records which merge points are live. A merge point is specified by the basic block in which it occurs, and the memoryBlock being merged.

stmtlocation_liveness_set livenessAnalyzer::_live_stmtlocations [private]

Live statement locations.
Set of live statements. Note that some kinds of statements are automatically live (for example, the return statement and all if statements.

stmt_liveness_set livenessAnalyzer::_live_stmts [private]

Live statements.
This set records which statements are live. It is really context-insensitive summary of the live statement locations.

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

Generated on Thu Jan 10 12:06:29 2002 for C-Breeze by

livenessAnalyzer Class Reference

Public Methods

Protected Methods

Private Types

Private Attributes

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation