historical/toontown-classic.git/panda/include/pipelineCyclerTrueImpl.I
2024-01-16 11:20:27 -06:00

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/**
* PANDA 3D SOFTWARE
* Copyright (c) Carnegie Mellon University. All rights reserved.
*
* All use of this software is subject to the terms of the revised BSD
* license. You should have received a copy of this license along
* with this source code in a file named "LICENSE."
*
* @file pipelineCyclerTrueImpl.I
* @author drose
* @date 2006-01-31
*/
/**
* Grabs an overall lock on the cycler. Release it with a call to release().
* This lock should be held while walking the list of stages.
*/
INLINE void PipelineCyclerTrueImpl::
acquire() {
TAU_PROFILE("void PipelineCyclerTrueImpl::acquire()", " ", TAU_USER);
_lock.acquire();
}
/**
* Grabs an overall lock on the cycler. Release it with a call to release().
* This lock should be held while walking the list of stages.
*/
INLINE void PipelineCyclerTrueImpl::
acquire(Thread *current_thread) {
TAU_PROFILE("void PipelineCyclerTrueImpl::acquire(Thread *)", " ", TAU_USER);
_lock.acquire(current_thread);
}
/**
* Release the overall lock on the cycler that was grabbed via acquire().
*/
INLINE void PipelineCyclerTrueImpl::
release() {
TAU_PROFILE("void PipelineCyclerTrueImpl::release()", " ", TAU_USER);
_lock.release();
}
/**
* Returns a const CycleData pointer, filled with the data for the current
* stage of the pipeline as seen by this thread. No lock is made on the
* contents; there is no guarantee that some other thread won't modify this
* object's data while you are working on it. (However, the data within the
* returned CycleData object itself is safe from modification; if another
* thread modifies the data, it will perform a copy-on-write, and thereby
* change the pointer stored within the object.)
*/
INLINE const CycleData *PipelineCyclerTrueImpl::
read_unlocked(Thread *current_thread) const {
TAU_PROFILE("const CycleData *PipelineCyclerTrueImpl::read_unlocked(Thread *)", " ", TAU_USER);
int pipeline_stage = current_thread->get_pipeline_stage();
#ifdef _DEBUG
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
#endif
return _data[pipeline_stage]._cdata;
}
/**
* Returns a const CycleData pointer, filled with the data for the current
* stage of the pipeline as seen by this thread. This pointer should
* eventually be released by calling release_read().
*
* There should be no outstanding write pointers on the data when this
* function is called.
*/
INLINE const CycleData *PipelineCyclerTrueImpl::
read(Thread *current_thread) const {
TAU_PROFILE("const CycleData *PipelineCyclerTrueImpl::read(Thread *)", " ", TAU_USER);
int pipeline_stage = current_thread->get_pipeline_stage();
#ifdef _DEBUG
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
#endif
_lock.acquire(current_thread);
return _data[pipeline_stage]._cdata;
}
/**
* Increments the count on a pointer previously retrieved by read(); now the
* pointer will need to be released twice.
*/
INLINE void PipelineCyclerTrueImpl::
increment_read(const CycleData *pointer) const {
TAU_PROFILE("void PipelineCyclerTrueImpl::increment_read(const CycleData *)", " ", TAU_USER);
#ifdef _DEBUG
int pipeline_stage = Thread::get_current_pipeline_stage();
nassertv(pipeline_stage >= 0 && pipeline_stage < _num_stages);
nassertv(_data[pipeline_stage]._cdata == pointer);
#endif
_lock.elevate_lock();
}
/**
* Releases a pointer previously obtained via a call to read().
*/
INLINE void PipelineCyclerTrueImpl::
release_read(const CycleData *pointer) const {
TAU_PROFILE("void PipelineCyclerTrueImpl::release_read(const CycleData *)", " ", TAU_USER);
#ifdef _DEBUG
int pipeline_stage = Thread::get_current_pipeline_stage();
nassertv(pipeline_stage >= 0 && pipeline_stage < _num_stages);
nassertv(_data[pipeline_stage]._cdata == pointer);
#endif
_lock.release();
}
/**
* Returns a non-const CycleData pointer, filled with a unique copy of the
* data for the current stage of the pipeline as seen by this thread. This
* pointer may now be used to write to the data, and that copy of the data
* will be propagated to all later stages of the pipeline. This pointer
* should eventually be released by calling release_write().
*
* There may only be one outstanding write pointer on a given stage at a time,
* and if there is a write pointer there may be no read pointers on the same
* stage (but see elevate_read).
*/
INLINE CycleData *PipelineCyclerTrueImpl::
write(Thread *current_thread) {
TAU_PROFILE("CycleData *PipelineCyclerTrueImpl::write(Thread *)", " ", TAU_USER);
return write_stage(current_thread->get_pipeline_stage(), current_thread);
}
/**
* This special variant on write() will automatically propagate changes back
* to upstream pipeline stages. If force_to_0 is false, then it propagates
* back only as long as the CycleData pointers are equivalent, guaranteeing
* that it does not modify upstream data (other than the modification that
* will be performed by the code that returns this pointer). This is
* particularly appropriate for minor updates, where it doesn't matter much if
* the update is lost, such as storing a cached value.
*
* If force_to_0 is true, then the CycleData pointer for the current pipeline
* stage is propagated all the way back up to stage 0; after this call, there
* will be only one CycleData pointer that is duplicated in all stages between
* stage 0 and the current stage. This may undo some recent changes that were
* made independently at pipeline stage 0 (or any other upstream stage).
* However, it guarantees that the change that is to be applied at this
* pipeline stage will stick. This is slightly dangerous because of the risk
* of losing upstream changes; generally, this should only be done when you
* are confident that there are no upstream changes to be lost (for instance,
* for an object that has been recently created).
*/
INLINE CycleData *PipelineCyclerTrueImpl::
write_upstream(bool force_to_0, Thread *current_thread) {
TAU_PROFILE("CycleData *PipelineCyclerTrueImpl::write_upstream(bool, Thread *)", " ", TAU_USER);
return write_stage_upstream(current_thread->get_pipeline_stage(), force_to_0,
current_thread);
}
/**
* Elevates a currently-held read pointer into a write pointer. This may or
* may not change the value of the pointer. It is only valid to do this if
* this is the only currently-outstanding read pointer on the current stage.
*/
INLINE CycleData *PipelineCyclerTrueImpl::
elevate_read(const CycleData *pointer, Thread *current_thread) {
TAU_PROFILE("CycleData *PipelineCyclerTrueImpl::elevate_read(const CycleData *)", " ", TAU_USER);
#ifdef _DEBUG
int pipeline_stage = current_thread->get_pipeline_stage();
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
nassertr(_data[pipeline_stage]._cdata == pointer, nullptr);
#endif
CycleData *new_pointer = write(current_thread);
_lock.release();
return new_pointer;
}
/**
* Elevates a currently-held read pointer into a write pointer, like
* elevate_read(), but also propagates the pointer back to upstream stages,
* like write_upstream().
*/
INLINE CycleData *PipelineCyclerTrueImpl::
elevate_read_upstream(const CycleData *pointer, bool force_to_0, Thread *current_thread) {
TAU_PROFILE("CycleData *PipelineCyclerTrueImpl::elevate_read_upstream(const CycleData *, bool)", " ", TAU_USER);
#ifdef _DEBUG
int pipeline_stage = current_thread->get_pipeline_stage();
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
nassertr(_data[pipeline_stage]._cdata == pointer, nullptr);
#endif
CycleData *new_pointer = write_upstream(force_to_0, current_thread);
_lock.release();
return new_pointer;
}
/**
* Increments the count on a pointer previously retrieved by write(); now the
* pointer will need to be released twice.
*/
INLINE void PipelineCyclerTrueImpl::
increment_write(CycleData *pointer) const {
TAU_PROFILE("void PipelineCyclerTrueImpl::increment_write(CycleData *)", " ", TAU_USER);
int pipeline_stage = Thread::get_current_pipeline_stage();
#ifdef _DEBUG
nassertv(pipeline_stage >= 0 && pipeline_stage < _num_stages);
nassertv(_data[pipeline_stage]._cdata == pointer);
#endif
++(_data[pipeline_stage]._writes_outstanding);
_lock.elevate_lock();
}
/**
* Releases a pointer previously obtained via a call to write().
*/
INLINE void PipelineCyclerTrueImpl::
release_write(CycleData *pointer) {
TAU_PROFILE("void PipelineCyclerTrueImpl::release_write(CycleData *)", " ", TAU_USER);
int pipeline_stage = Thread::get_current_pipeline_stage();
return release_write_stage(pipeline_stage, pointer);
}
/**
* Returns the number of stages in the pipeline.
*/
INLINE int PipelineCyclerTrueImpl::
get_num_stages() {
return _num_stages;
}
/**
* Returns a const CycleData pointer, filled with the data for the indicated
* stage of the pipeline. As in read_unlocked(), no lock is held on the
* returned pointer.
*/
INLINE const CycleData *PipelineCyclerTrueImpl::
read_stage_unlocked(int pipeline_stage) const {
TAU_PROFILE("const CycleData *PipelineCyclerTrueImpl::read_stage_unlocked(int)", " ", TAU_USER);
#ifdef _DEBUG
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
#elif defined(__has_builtin) && __has_builtin(__builtin_assume)
__builtin_assume(pipeline_stage >= 0);
#endif
return _data[pipeline_stage]._cdata;
}
/**
* Returns a const CycleData pointer, filled with the data for the indicated
* stage of the pipeline. This pointer should eventually be released by
* calling release_read_stage().
*
* There should be no outstanding write pointers on the data when this
* function is called.
*/
INLINE const CycleData *PipelineCyclerTrueImpl::
read_stage(int pipeline_stage, Thread *current_thread) const {
TAU_PROFILE("const CycleData *PipelineCyclerTrueImpl::read_stage(int, Thread *)", " ", TAU_USER);
#ifdef _DEBUG
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
#elif defined(__has_builtin) && __has_builtin(__builtin_assume)
__builtin_assume(pipeline_stage >= 0);
#endif
_lock.acquire(current_thread);
return _data[pipeline_stage]._cdata;
}
/**
* Releases a pointer previously obtained via a call to read_stage().
*/
INLINE void PipelineCyclerTrueImpl::
release_read_stage(int pipeline_stage, const CycleData *pointer) const {
TAU_PROFILE("void PipelineCyclerTrueImpl::release_read_stage(int, const CycleData *)", " ", TAU_USER);
#ifdef _DEBUG
nassertv(pipeline_stage >= 0 && pipeline_stage < _num_stages);
nassertv(_data[pipeline_stage]._cdata == pointer);
#endif
_lock.release();
}
/**
* Elevates a currently-held read pointer into a write pointer. This may or
* may not change the value of the pointer. It is only valid to do this if
* this is the only currently-outstanding read pointer on the indicated stage.
*/
INLINE CycleData *PipelineCyclerTrueImpl::
elevate_read_stage(int pipeline_stage, const CycleData *pointer,
Thread *current_thread) {
TAU_PROFILE("CycleData *PipelineCyclerTrueImpl::elevate_read_stage(int, const CycleData *)", " ", TAU_USER);
#ifdef _DEBUG
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
nassertr(_data[pipeline_stage]._cdata == pointer, nullptr);
#elif defined(__has_builtin) && __has_builtin(__builtin_assume)
__builtin_assume(pipeline_stage >= 0);
#endif
CycleData *new_pointer = write_stage(pipeline_stage, current_thread);
_lock.release();
return new_pointer;
}
/**
* Elevates a currently-held read pointer into a write pointer. This may or
* may not change the value of the pointer. It is only valid to do this if
* this is the only currently-outstanding read pointer on the indicated stage.
*/
INLINE CycleData *PipelineCyclerTrueImpl::
elevate_read_stage_upstream(int pipeline_stage, const CycleData *pointer,
bool force_to_0, Thread *current_thread) {
TAU_PROFILE("CycleData *PipelineCyclerTrueImpl::elevate_read_stage(int, const CycleData *)", " ", TAU_USER);
#ifdef _DEBUG
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
nassertr(_data[pipeline_stage]._cdata == pointer, nullptr);
#elif defined(__has_builtin) && __has_builtin(__builtin_assume)
__builtin_assume(pipeline_stage >= 0);
#endif
CycleData *new_pointer =
write_stage_upstream(pipeline_stage, force_to_0, current_thread);
_lock.release();
return new_pointer;
}
/**
* Releases a pointer previously obtained via a call to write_stage().
*/
INLINE void PipelineCyclerTrueImpl::
release_write_stage(int pipeline_stage, CycleData *pointer) {
TAU_PROFILE("void PipelineCyclerTrueImpl::release_write_stage(int, const CycleData *)", " ", TAU_USER);
#ifdef _DEBUG
nassertv(pipeline_stage >= 0 && pipeline_stage < _num_stages);
nassertv(_data[pipeline_stage]._cdata == pointer);
nassertv(_data[pipeline_stage]._writes_outstanding > 0);
#elif defined(__has_builtin) && __has_builtin(__builtin_assume)
__builtin_assume(pipeline_stage >= 0);
#endif
--(_data[pipeline_stage]._writes_outstanding);
_lock.release();
}
/**
* Returns the type of object that owns this cycler, as reported by
* CycleData::get_parent_type().
*/
INLINE TypeHandle PipelineCyclerTrueImpl::
get_parent_type() const {
return _data[0]._cdata->get_parent_type();
}
/**
* Returns a pointer without counting it. This is only intended for use as
* the return value for certain nassertr() functions, so the application can
* recover after a failure to manage the read and write pointers correctly.
* You should never call this function directly.
*/
INLINE CycleData *PipelineCyclerTrueImpl::
cheat() const {
TAU_PROFILE("CycleData *PipelineCyclerTrueImpl::cheat()", " ", TAU_USER);
int pipeline_stage = Thread::get_current_pipeline_stage();
nassertr(pipeline_stage >= 0 && pipeline_stage < _num_stages, nullptr);
return _data[pipeline_stage]._cdata;
}
/**
* Returns the number of handles currently outstanding to read the current
* stage of the data. This should only be used for debugging purposes.
*/
INLINE int PipelineCyclerTrueImpl::
get_read_count() const {
return 0;
}
/**
* Returns the number of handles currently outstanding to read the current
* stage of the data. This will normally only be either 0 or 1. This should
* only be used for debugging purposes.
*/
INLINE int PipelineCyclerTrueImpl::
get_write_count() const {
return 0;
}
/**
* This is a special implementation of cycle() for the special case of just
* two stages to the pipeline. It does the same thing as cycle(), but is a
* little bit faster because it knows there are exactly two stages.
*/
INLINE PT(CycleData) PipelineCyclerTrueImpl::
cycle_2() {
TAU_PROFILE("PT(CycleData) PipelineCyclerTrueImpl::cycle_2()", " ", TAU_USER);
// This trick moves an NPT into a PT without unnecessarily incrementing and
// subsequently decrementing the regular reference count.
PT(CycleData) last_val;
last_val.swap(_data[1]._cdata);
last_val->node_unref_only();
nassertr(_lock.debug_is_locked(), last_val);
nassertr(_dirty, last_val);
nassertr(_num_stages == 2, last_val);
nassertr(_data[1]._writes_outstanding == 0, last_val);
_data[1]._cdata = _data[0]._cdata;
// No longer dirty.
_dirty = 0;
return last_val;
}
/**
* This is a special implementation of cycle() for the special case of exactly
* three stages to the pipeline. It does the same thing as cycle(), but is a
* little bit faster because it knows there are exactly three stages.
*/
INLINE PT(CycleData) PipelineCyclerTrueImpl::
cycle_3() {
TAU_PROFILE("PT(CycleData) PipelineCyclerTrueImpl::cycle_3()", " ", TAU_USER);
// This trick moves an NPT into a PT without unnecessarily incrementing and
// subsequently decrementing the regular reference count.
PT(CycleData) last_val;
last_val.swap(_data[2]._cdata);
last_val->node_unref_only();
nassertr(_lock.debug_is_locked(), last_val);
nassertr(_dirty, last_val);
nassertr(_num_stages == 3, last_val);
nassertr(_data[2]._writes_outstanding == 0, last_val);
nassertr(_data[1]._writes_outstanding == 0, last_val);
_data[2]._cdata = _data[1]._cdata;
_data[1]._cdata = _data[0]._cdata;
if (_data[2]._cdata == _data[1]._cdata) {
// No longer dirty.
_dirty = 0;
}
return last_val;
}
/**
*
*/
INLINE PipelineCyclerTrueImpl::CyclerMutex::
CyclerMutex(PipelineCyclerTrueImpl *cycler) {
#ifdef DEBUG_THREADS
_cycler = cycler;
#endif
}
/**
*
*/
INLINE PipelineCyclerTrueImpl::CycleDataNode::
CycleDataNode() :
_writes_outstanding(0)
{
}
/**
*
*/
INLINE PipelineCyclerTrueImpl::CycleDataNode::
CycleDataNode(const PipelineCyclerTrueImpl::CycleDataNode &copy) :
_cdata(copy._cdata),
_writes_outstanding(0)
{
}
/**
*
*/
INLINE PipelineCyclerTrueImpl::CycleDataNode::
~CycleDataNode() {
nassertv(_writes_outstanding == 0);
}
/**
*
*/
INLINE void PipelineCyclerTrueImpl::CycleDataNode::
operator = (const PipelineCyclerTrueImpl::CycleDataNode &copy) {
_cdata = copy._cdata;
}