gpu/command_buffer/client/share_group.cc - chromium/src - Git at Google

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "gpu/command_buffer/client/share_group.h"

 #include <stdint.h>

 #include <vector>

 #include "base/containers/stack.h"
 #include "base/logging.h"
 #include "base/synchronization/lock.h"
 #include "gpu/command_buffer/client/gles2_cmd_helper.h"
 #include "gpu/command_buffer/client/gles2_implementation.h"
 #include "gpu/command_buffer/client/program_info_manager.h"
 #include "gpu/command_buffer/common/id_allocator.h"

 namespace gpu {
 namespace gles2 {

 ShareGroupContextData::IdHandlerData::IdHandlerData() : flush_generation_(0) {}
 ShareGroupContextData::IdHandlerData::~IdHandlerData() = default;

 static_assert(gpu::kInvalidResource == 0,
               "GL expects kInvalidResource to be 0");

 // The standard id handler.
 class IdHandler : public IdHandlerInterface {
  public:
   IdHandler() = default;
   ~IdHandler() override = default;

   // Overridden from IdHandlerInterface.
   void MakeIds(GLES2Implementation* /* gl_impl */,
                GLuint id_offset,
                GLsizei n,
                GLuint* ids) override {
     base::AutoLock auto_lock(lock_);
     if (id_offset == 0) {
       for (GLsizei ii = 0; ii < n; ++ii) {
         ids[ii] = id_allocator_.AllocateID();
       }
     } else {
       for (GLsizei ii = 0; ii < n; ++ii) {
         ids[ii] = id_allocator_.AllocateIDAtOrAbove(id_offset);
         id_offset = ids[ii] + 1;
       }
     }
   }

   // Overridden from IdHandlerInterface.
   bool FreeIds(GLES2Implementation* gl_impl,
                GLsizei n,
                const GLuint* ids,
                DeleteFn delete_fn) override {
     base::AutoLock auto_lock(lock_);

     for (GLsizei ii = 0; ii < n; ++ii) {
       id_allocator_.FreeID(ids[ii]);
     }

     (gl_impl->*delete_fn)(n, ids);
     // We need to ensure that the delete call is evaluated on the service side
     // before any other contexts issue commands using these client ids.
     gl_impl->helper()->CommandBufferHelper::OrderingBarrier();
     return true;
   }

   // Overridden from IdHandlerInterface.
   bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
                          GLenum target,
                          GLuint id,
                          BindFn bind_fn) override {
     base::AutoLock auto_lock(lock_);
     bool result = id ? id_allocator_.MarkAsUsed(id) : true;
     (gl_impl->*bind_fn)(target, id);
     return result;
   }
   bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
                          GLenum target,
                          GLuint index,
                          GLuint id,
                          BindIndexedFn bind_fn) override {
     base::AutoLock auto_lock(lock_);
     bool result = id ? id_allocator_.MarkAsUsed(id) : true;
     (gl_impl->*bind_fn)(target, index, id);
     return result;
   }
   bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
                          GLenum target,
                          GLuint index,
                          GLuint id,
                          GLintptr offset,
                          GLsizeiptr size,
                          BindIndexedRangeFn bind_fn) override {
     base::AutoLock auto_lock(lock_);
     bool result = id ? id_allocator_.MarkAsUsed(id) : true;
     (gl_impl->*bind_fn)(target, index, id, offset, size);
     return result;
   }

   void FreeContext(GLES2Implementation* gl_impl) override {}

  private:
   base::Lock lock_;
   IdAllocator id_allocator_;
 };

 // An id handler that requires Gen before Bind.
 class StrictIdHandler : public IdHandlerInterface {
  public:
   explicit StrictIdHandler(int id_namespace) : id_namespace_(id_namespace) {}
   ~StrictIdHandler() override = default;

   // Overridden from IdHandler.
   void MakeIds(GLES2Implementation* gl_impl,
                GLuint /* id_offset */,
                GLsizei n,
                GLuint* ids) override {
     base::AutoLock auto_lock(lock_);

     // Collect pending FreeIds from other flush_generation.
     CollectPendingFreeIds(gl_impl);

     for (GLsizei ii = 0; ii < n; ++ii) {
       if (!free_ids_.empty()) {
         // Allocate a previously freed Id.
         ids[ii] = free_ids_.top();
         free_ids_.pop();

         // Record kIdInUse state.
         DCHECK(id_states_[ids[ii] - 1] == kIdFree);
         id_states_[ids[ii] - 1] = kIdInUse;
       } else {
         // Allocate a new Id.
         id_states_.push_back(kIdInUse);
         ids[ii] = id_states_.size();
       }
     }
   }

   // Overridden from IdHandler.
   bool FreeIds(GLES2Implementation* gl_impl,
                GLsizei n,
                const GLuint* ids,
                DeleteFn delete_fn) override {
     // Delete stub must run before CollectPendingFreeIds.
     (gl_impl->*delete_fn)(n, ids);

     bool return_value = true;

     {
       base::AutoLock auto_lock(lock_);

       // Collect pending FreeIds from other flush_generation.
       CollectPendingFreeIds(gl_impl);

       // Save Ids to free in a later flush_generation.
       ShareGroupContextData::IdHandlerData* ctxt_data =
           gl_impl->share_group_context_data()->id_handler_data(id_namespace_);

       GLuint max_valid_id = id_states_.size();
       for (GLsizei ii = 0; ii < n; ++ii) {
         GLuint id = ids[ii];
         if (id != 0) {
           if (id > max_valid_id) {
             // Caller will generate an error.
             return_value = false;
             continue;
           }
           // Save freed Id for later.
           if (id_states_[id - 1] != kIdInUse) {
             DVLOG(1) << "Already freed id " << id;
             return_value = false;
             continue;
           }
           id_states_[id - 1] = kIdPendingFree;
           ctxt_data->freed_ids_.push_back(id);
         }
       }
     }

     return return_value;
   }

   // Overridden from IdHandler.
   bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
                          GLenum target,
                          GLuint id,
                          BindFn bind_fn) override {
 #ifndef NDEBUG
     if (id != 0) {
       base::AutoLock auto_lock(lock_);
       DCHECK(id_states_[id - 1] == kIdInUse);
     }
 #endif
     // StrictIdHandler is used if |bind_generates_resource| is false. In that
     // case, |bind_fn| will not use Flush() after helper->Bind*(), so it is OK
     // to call |bind_fn| without holding the lock.
     (gl_impl->*bind_fn)(target, id);
     return true;
   }
   bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
                          GLenum target,
                          GLuint index,
                          GLuint id,
                          BindIndexedFn bind_fn) override {
 #ifndef NDEBUG
     if (id != 0) {
       base::AutoLock auto_lock(lock_);
       DCHECK(id_states_[id - 1] == kIdInUse);
     }
 #endif
     // StrictIdHandler is used if |bind_generates_resource| is false. In that
     // case, |bind_fn| will not use Flush() after helper->Bind*(), so it is OK
     // to call |bind_fn| without holding the lock.
     (gl_impl->*bind_fn)(target, index, id);
     return true;
   }
   bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
                          GLenum target,
                          GLuint index,
                          GLuint id,
                          GLintptr offset,
                          GLsizeiptr size,
                          BindIndexedRangeFn bind_fn) override {
 #ifndef NDEBUG
     if (id != 0) {
       base::AutoLock auto_lock(lock_);
       DCHECK(id_states_[id - 1] == kIdInUse);
     }
 #endif
     // StrictIdHandler is used if |bind_generates_resource| is false. In that
     // case, |bind_fn| will not use Flush() after helper->Bind*(), so it is OK
     // to call |bind_fn| without holding the lock.
     (gl_impl->*bind_fn)(target, index, id, offset, size);
     return true;
   }

   // Overridden from IdHandlerInterface.
   void FreeContext(GLES2Implementation* gl_impl) override {
     base::AutoLock auto_lock(lock_);
     CollectPendingFreeIds(gl_impl);
   }

  private:
   enum IdState { kIdFree, kIdPendingFree, kIdInUse };

   void CollectPendingFreeIds(GLES2Implementation* gl_impl) {
     uint32_t flush_generation = gl_impl->helper()->flush_generation();
     ShareGroupContextData::IdHandlerData* ctxt_data =
         gl_impl->share_group_context_data()->id_handler_data(id_namespace_);

     if (ctxt_data->flush_generation_ != flush_generation) {
       ctxt_data->flush_generation_ = flush_generation;
       for (uint32_t ii = 0; ii < ctxt_data->freed_ids_.size(); ++ii) {
         const GLuint id = ctxt_data->freed_ids_[ii];
         DCHECK(id_states_[id - 1] == kIdPendingFree);
         id_states_[id - 1] = kIdFree;
         free_ids_.push(id);
       }
       ctxt_data->freed_ids_.clear();
     }
   }

   int id_namespace_;

   base::Lock lock_;
   std::vector<uint8_t> id_states_;
   base::stack<uint32_t> free_ids_;
 };

 // An id handler for ids that are never reused.
 class NonReusedIdHandler : public IdHandlerInterface {
  public:
   NonReusedIdHandler() : last_id_(0) {}
   ~NonReusedIdHandler() override = default;

   // Overridden from IdHandlerInterface.
   void MakeIds(GLES2Implementation* /* gl_impl */,
                GLuint id_offset,
                GLsizei n,
                GLuint* ids) override {
     base::AutoLock auto_lock(lock_);
     for (GLsizei ii = 0; ii < n; ++ii) {
       ids[ii] = ++last_id_ + id_offset;
     }
   }

   // Overridden from IdHandlerInterface.
   bool FreeIds(GLES2Implementation* gl_impl,
                GLsizei n,
                const GLuint* ids,
                DeleteFn delete_fn) override {
     // Ids are never freed.
     (gl_impl->*delete_fn)(n, ids);
     return true;
   }

   // Overridden from IdHandlerInterface.
   bool MarkAsUsedForBind(GLES2Implementation* /* gl_impl */,
                          GLenum /* target */,
                          GLuint /* id */,
                          BindFn /* bind_fn */) override {
     // This is only used for Shaders and Programs which have no bind.
     return false;
   }
   bool MarkAsUsedForBind(GLES2Implementation* /* gl_impl */,
                          GLenum /* target */,
                          GLuint /* index */,
                          GLuint /* id */,
                          BindIndexedFn /* bind_fn */) override {
     // This is only used for Shaders and Programs which have no bind.
     return false;
   }
   bool MarkAsUsedForBind(GLES2Implementation* /* gl_impl */,
                          GLenum /* target */,
                          GLuint /* index */,
                          GLuint /* id */,
                          GLintptr /* offset */,
                          GLsizeiptr /* size */,
                          BindIndexedRangeFn /* bind_fn */) override {
     // This is only used for Shaders and Programs which have no bind.
     return false;
   }

   void FreeContext(GLES2Implementation* gl_impl) override {}

  private:
   base::Lock lock_;
   GLuint last_id_;
 };

 class RangeIdHandler : public RangeIdHandlerInterface {
  public:
   RangeIdHandler() = default;

   void MakeIdRange(GLES2Implementation* /*gl_impl*/,
                    GLsizei n,
                    GLuint* first_id) override {
     base::AutoLock auto_lock(lock_);
     *first_id = id_allocator_.AllocateIDRange(n);
   }

   void FreeIdRange(GLES2Implementation* gl_impl,
                    const GLuint first_id,
                    GLsizei range,
                    DeleteRangeFn delete_fn) override {
     base::AutoLock auto_lock(lock_);
     DCHECK(range > 0);
     id_allocator_.FreeIDRange(first_id, range);
     (gl_impl->*delete_fn)(first_id, range);
     gl_impl->helper()->CommandBufferHelper::OrderingBarrier();
   }

   void FreeContext(GLES2Implementation* gl_impl) override {}

  private:
   base::Lock lock_;
   IdAllocator id_allocator_;
 };

 ShareGroup::ShareGroup(bool bind_generates_resource, uint64_t tracing_guid)
     : bind_generates_resource_(bind_generates_resource),
       tracing_guid_(tracing_guid) {
   if (bind_generates_resource) {
     for (int i = 0;
          i < static_cast<int>(SharedIdNamespaces::kNumSharedIdNamespaces);
          ++i) {
       if (i == static_cast<int>(SharedIdNamespaces::kProgramsAndShaders)) {
         id_handlers_[i].reset(new NonReusedIdHandler());
       } else {
         id_handlers_[i].reset(new IdHandler());
       }
     }
   } else {
     for (int i = 0;
          i < static_cast<int>(SharedIdNamespaces::kNumSharedIdNamespaces);
          ++i) {
       if (i == static_cast<int>(SharedIdNamespaces::kProgramsAndShaders)) {
         id_handlers_[i].reset(new NonReusedIdHandler());
       } else {
         id_handlers_[i].reset(new StrictIdHandler(i));
       }
     }
   }
   program_info_manager_.reset(new ProgramInfoManager);
   for (auto& range_id_handler : range_id_handlers_) {
     range_id_handler.reset(new RangeIdHandler());
   }
 }

 void ShareGroup::Lose() {
   base::AutoLock hold(lost_lock_);
   lost_ = true;
 }

 bool ShareGroup::IsLost() const {
   base::AutoLock hold(lost_lock_);
   return lost_;
 }

 void ShareGroup::SetProgramInfoManagerForTesting(ProgramInfoManager* manager) {
   program_info_manager_.reset(manager);
 }

 ShareGroup::~ShareGroup() = default;

 }  // namespace gles2
 }  // namespace gpu
	// Copyright (c) 2012 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "gpu/command_buffer/client/share_group.h"

	#include <stdint.h>

	#include <vector>

	#include "base/containers/stack.h"
	#include "base/logging.h"
	#include "base/synchronization/lock.h"
	#include "gpu/command_buffer/client/gles2_cmd_helper.h"
	#include "gpu/command_buffer/client/gles2_implementation.h"
	#include "gpu/command_buffer/client/program_info_manager.h"
	#include "gpu/command_buffer/common/id_allocator.h"

	namespace gpu {
	namespace gles2 {

	ShareGroupContextData::IdHandlerData::IdHandlerData() : flush_generation_(0) {}
	ShareGroupContextData::IdHandlerData::~IdHandlerData() = default;

	static_assert(gpu::kInvalidResource == 0,
	"GL expects kInvalidResource to be 0");

	// The standard id handler.
	class IdHandler : public IdHandlerInterface {
	public:
	IdHandler() = default;
	~IdHandler() override = default;

	// Overridden from IdHandlerInterface.
	void MakeIds(GLES2Implementation* /* gl_impl */,
	GLuint id_offset,
	GLsizei n,
	GLuint* ids) override {
	base::AutoLock auto_lock(lock_);
	if (id_offset == 0) {
	for (GLsizei ii = 0; ii < n; ++ii) {
	ids[ii] = id_allocator_.AllocateID();
	}
	} else {
	for (GLsizei ii = 0; ii < n; ++ii) {
	ids[ii] = id_allocator_.AllocateIDAtOrAbove(id_offset);
	id_offset = ids[ii] + 1;
	}
	}
	}

	// Overridden from IdHandlerInterface.
	bool FreeIds(GLES2Implementation* gl_impl,
	GLsizei n,
	const GLuint* ids,
	DeleteFn delete_fn) override {
	base::AutoLock auto_lock(lock_);

	for (GLsizei ii = 0; ii < n; ++ii) {
	id_allocator_.FreeID(ids[ii]);
	}

	(gl_impl->*delete_fn)(n, ids);
	// We need to ensure that the delete call is evaluated on the service side
	// before any other contexts issue commands using these client ids.
	gl_impl->helper()->CommandBufferHelper::OrderingBarrier();
	return true;
	}

	// Overridden from IdHandlerInterface.
	bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
	GLenum target,
	GLuint id,
	BindFn bind_fn) override {
	base::AutoLock auto_lock(lock_);
	bool result = id ? id_allocator_.MarkAsUsed(id) : true;
	(gl_impl->*bind_fn)(target, id);
	return result;
	}
	bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
	GLenum target,
	GLuint index,
	GLuint id,
	BindIndexedFn bind_fn) override {
	base::AutoLock auto_lock(lock_);
	bool result = id ? id_allocator_.MarkAsUsed(id) : true;
	(gl_impl->*bind_fn)(target, index, id);
	return result;
	}
	bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
	GLenum target,
	GLuint index,
	GLuint id,
	GLintptr offset,
	GLsizeiptr size,
	BindIndexedRangeFn bind_fn) override {
	base::AutoLock auto_lock(lock_);
	bool result = id ? id_allocator_.MarkAsUsed(id) : true;
	(gl_impl->*bind_fn)(target, index, id, offset, size);
	return result;
	}

	void FreeContext(GLES2Implementation* gl_impl) override {}

	private:
	base::Lock lock_;
	IdAllocator id_allocator_;
	};

	// An id handler that requires Gen before Bind.
	class StrictIdHandler : public IdHandlerInterface {
	public:
	explicit StrictIdHandler(int id_namespace) : id_namespace_(id_namespace) {}
	~StrictIdHandler() override = default;

	// Overridden from IdHandler.
	void MakeIds(GLES2Implementation* gl_impl,
	GLuint /* id_offset */,
	GLsizei n,
	GLuint* ids) override {
	base::AutoLock auto_lock(lock_);

	// Collect pending FreeIds from other flush_generation.
	CollectPendingFreeIds(gl_impl);

	for (GLsizei ii = 0; ii < n; ++ii) {
	if (!free_ids_.empty()) {
	// Allocate a previously freed Id.
	ids[ii] = free_ids_.top();
	free_ids_.pop();

	// Record kIdInUse state.
	DCHECK(id_states_[ids[ii] - 1] == kIdFree);
	id_states_[ids[ii] - 1] = kIdInUse;
	} else {
	// Allocate a new Id.
	id_states_.push_back(kIdInUse);
	ids[ii] = id_states_.size();
	}
	}
	}

	// Overridden from IdHandler.
	bool FreeIds(GLES2Implementation* gl_impl,
	GLsizei n,
	const GLuint* ids,
	DeleteFn delete_fn) override {
	// Delete stub must run before CollectPendingFreeIds.
	(gl_impl->*delete_fn)(n, ids);

	bool return_value = true;

	{
	base::AutoLock auto_lock(lock_);

	// Collect pending FreeIds from other flush_generation.
	CollectPendingFreeIds(gl_impl);

	// Save Ids to free in a later flush_generation.
	ShareGroupContextData::IdHandlerData* ctxt_data =
	gl_impl->share_group_context_data()->id_handler_data(id_namespace_);

	GLuint max_valid_id = id_states_.size();
	for (GLsizei ii = 0; ii < n; ++ii) {
	GLuint id = ids[ii];
	if (id != 0) {
	if (id > max_valid_id) {
	// Caller will generate an error.
	return_value = false;
	continue;
	}
	// Save freed Id for later.
	if (id_states_[id - 1] != kIdInUse) {
	DVLOG(1) << "Already freed id " << id;
	return_value = false;
	continue;
	}
	id_states_[id - 1] = kIdPendingFree;
	ctxt_data->freed_ids_.push_back(id);
	}
	}
	}

	return return_value;
	}

	// Overridden from IdHandler.
	bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
	GLenum target,
	GLuint id,
	BindFn bind_fn) override {
	#ifndef NDEBUG
	if (id != 0) {
	base::AutoLock auto_lock(lock_);
	DCHECK(id_states_[id - 1] == kIdInUse);
	}
	#endif
	// StrictIdHandler is used if \|bind_generates_resource\| is false. In that
	// case, \|bind_fn\| will not use Flush() after helper->Bind*(), so it is OK
	// to call \|bind_fn\| without holding the lock.
	(gl_impl->*bind_fn)(target, id);
	return true;
	}
	bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
	GLenum target,
	GLuint index,
	GLuint id,
	BindIndexedFn bind_fn) override {
	#ifndef NDEBUG
	if (id != 0) {
	base::AutoLock auto_lock(lock_);
	DCHECK(id_states_[id - 1] == kIdInUse);
	}
	#endif
	// StrictIdHandler is used if \|bind_generates_resource\| is false. In that
	// case, \|bind_fn\| will not use Flush() after helper->Bind*(), so it is OK
	// to call \|bind_fn\| without holding the lock.
	(gl_impl->*bind_fn)(target, index, id);
	return true;
	}
	bool MarkAsUsedForBind(GLES2Implementation* gl_impl,
	GLenum target,
	GLuint index,
	GLuint id,
	GLintptr offset,
	GLsizeiptr size,
	BindIndexedRangeFn bind_fn) override {
	#ifndef NDEBUG
	if (id != 0) {
	base::AutoLock auto_lock(lock_);
	DCHECK(id_states_[id - 1] == kIdInUse);
	}
	#endif
	// StrictIdHandler is used if \|bind_generates_resource\| is false. In that
	// case, \|bind_fn\| will not use Flush() after helper->Bind*(), so it is OK
	// to call \|bind_fn\| without holding the lock.
	(gl_impl->*bind_fn)(target, index, id, offset, size);
	return true;
	}

	// Overridden from IdHandlerInterface.
	void FreeContext(GLES2Implementation* gl_impl) override {
	base::AutoLock auto_lock(lock_);
	CollectPendingFreeIds(gl_impl);
	}

	private:
	enum IdState { kIdFree, kIdPendingFree, kIdInUse };

	void CollectPendingFreeIds(GLES2Implementation* gl_impl) {
	uint32_t flush_generation = gl_impl->helper()->flush_generation();
	ShareGroupContextData::IdHandlerData* ctxt_data =
	gl_impl->share_group_context_data()->id_handler_data(id_namespace_);

	if (ctxt_data->flush_generation_ != flush_generation) {
	ctxt_data->flush_generation_ = flush_generation;
	for (uint32_t ii = 0; ii < ctxt_data->freed_ids_.size(); ++ii) {
	const GLuint id = ctxt_data->freed_ids_[ii];
	DCHECK(id_states_[id - 1] == kIdPendingFree);
	id_states_[id - 1] = kIdFree;
	free_ids_.push(id);
	}
	ctxt_data->freed_ids_.clear();
	}
	}

	int id_namespace_;

	base::Lock lock_;
	std::vector<uint8_t> id_states_;
	base::stack<uint32_t> free_ids_;
	};

	// An id handler for ids that are never reused.
	class NonReusedIdHandler : public IdHandlerInterface {
	public:
	NonReusedIdHandler() : last_id_(0) {}
	~NonReusedIdHandler() override = default;

	// Overridden from IdHandlerInterface.
	void MakeIds(GLES2Implementation* /* gl_impl */,
	GLuint id_offset,
	GLsizei n,
	GLuint* ids) override {
	base::AutoLock auto_lock(lock_);
	for (GLsizei ii = 0; ii < n; ++ii) {
	ids[ii] = ++last_id_ + id_offset;
	}
	}

	// Overridden from IdHandlerInterface.
	bool FreeIds(GLES2Implementation* gl_impl,
	GLsizei n,
	const GLuint* ids,
	DeleteFn delete_fn) override {
	// Ids are never freed.
	(gl_impl->*delete_fn)(n, ids);
	return true;
	}

	// Overridden from IdHandlerInterface.
	bool MarkAsUsedForBind(GLES2Implementation* /* gl_impl */,
	GLenum /* target */,
	GLuint /* id */,
	BindFn /* bind_fn */) override {
	// This is only used for Shaders and Programs which have no bind.
	return false;
	}
	bool MarkAsUsedForBind(GLES2Implementation* /* gl_impl */,
	GLenum /* target */,
	GLuint /* index */,
	GLuint /* id */,
	BindIndexedFn /* bind_fn */) override {
	// This is only used for Shaders and Programs which have no bind.
	return false;
	}
	bool MarkAsUsedForBind(GLES2Implementation* /* gl_impl */,
	GLenum /* target */,
	GLuint /* index */,
	GLuint /* id */,
	GLintptr /* offset */,
	GLsizeiptr /* size */,
	BindIndexedRangeFn /* bind_fn */) override {
	// This is only used for Shaders and Programs which have no bind.
	return false;
	}

	void FreeContext(GLES2Implementation* gl_impl) override {}

	private:
	base::Lock lock_;
	GLuint last_id_;
	};

	class RangeIdHandler : public RangeIdHandlerInterface {
	public:
	RangeIdHandler() = default;

	void MakeIdRange(GLES2Implementation* /gl_impl/,
	GLsizei n,
	GLuint* first_id) override {
	base::AutoLock auto_lock(lock_);
	*first_id = id_allocator_.AllocateIDRange(n);
	}

	void FreeIdRange(GLES2Implementation* gl_impl,
	const GLuint first_id,
	GLsizei range,
	DeleteRangeFn delete_fn) override {
	base::AutoLock auto_lock(lock_);
	DCHECK(range > 0);
	id_allocator_.FreeIDRange(first_id, range);
	(gl_impl->*delete_fn)(first_id, range);
	gl_impl->helper()->CommandBufferHelper::OrderingBarrier();
	}

	void FreeContext(GLES2Implementation* gl_impl) override {}

	private:
	base::Lock lock_;
	IdAllocator id_allocator_;
	};

	ShareGroup::ShareGroup(bool bind_generates_resource, uint64_t tracing_guid)
	: bind_generates_resource_(bind_generates_resource),
	tracing_guid_(tracing_guid) {
	if (bind_generates_resource) {
	for (int i = 0;
	i < static_cast<int>(SharedIdNamespaces::kNumSharedIdNamespaces);
	++i) {
	if (i == static_cast<int>(SharedIdNamespaces::kProgramsAndShaders)) {
	id_handlers_[i].reset(new NonReusedIdHandler());
	} else {
	id_handlers_[i].reset(new IdHandler());
	}
	}
	} else {
	for (int i = 0;
	i < static_cast<int>(SharedIdNamespaces::kNumSharedIdNamespaces);
	++i) {
	if (i == static_cast<int>(SharedIdNamespaces::kProgramsAndShaders)) {
	id_handlers_[i].reset(new NonReusedIdHandler());
	} else {
	id_handlers_[i].reset(new StrictIdHandler(i));
	}
	}
	}
	program_info_manager_.reset(new ProgramInfoManager);
	for (auto& range_id_handler : range_id_handlers_) {
	range_id_handler.reset(new RangeIdHandler());
	}
	}

	void ShareGroup::Lose() {
	base::AutoLock hold(lost_lock_);
	lost_ = true;
	}

	bool ShareGroup::IsLost() const {
	base::AutoLock hold(lost_lock_);
	return lost_;
	}

	void ShareGroup::SetProgramInfoManagerForTesting(ProgramInfoManager* manager) {
	program_info_manager_.reset(manager);
	}

	ShareGroup::~ShareGroup() = default;

	} // namespace gles2
	} // namespace gpu