Use client side arrays for GL_STREAM_DRAW attributes

gpu/command_buffer/service/buffer_manager.cc

Index: gpu/command_buffer/service/buffer_manager.cc
diff --git a/gpu/command_buffer/service/buffer_manager.cc b/gpu/command_buffer/service/buffer_manager.cc
index cb3062afb602827e3d4911cec9a8d8d97119f328..576fb846b21961432fa2ca24f925eba3aa9b6da6 100644
--- a/gpu/command_buffer/service/buffer_manager.cc
+++ b/gpu/command_buffer/service/buffer_manager.cc
@@ -7,15 +7,19 @@
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "gpu/command_buffer/common/gles2_cmd_utils.h"
+#include "gpu/command_buffer/service/feature_info.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 #include "gpu/command_buffer/service/memory_tracking.h"
 
 namespace gpu {
 namespace gles2 {
 
-BufferManager::BufferManager(MemoryTracker* memory_tracker)
+BufferManager::BufferManager(
+    MemoryTracker* memory_tracker,
+    FeatureInfo* feature_info)
     : memory_tracker_(
           new MemoryTypeTracker(memory_tracker, MemoryTracker::kManaged)),
+      feature_info_(feature_info),
       allow_buffers_on_multiple_targets_(false),
       buffer_info_count_(0),
       have_context_(true) {
@@ -70,7 +74,8 @@ Buffer::Buffer(BufferManager* manager, GLuint service_id)
       target_(0),
       size_(0),
       usage_(GL_STATIC_DRAW),
-      shadowed_(false) {
+      shadowed_(false),
+      is_client_side_array_(false) {
   manager_->StartTracking(this);
 }
 
@@ -86,17 +91,26 @@ Buffer::~Buffer() {
 }
 
 void Buffer::SetInfo(
-    GLsizeiptr size, GLenum usage, bool shadow) {
+    GLsizeiptr size, GLenum usage, bool shadow, const GLvoid* data,
+    bool is_client_side_array) {
   usage_ = usage;
+  is_client_side_array_ = is_client_side_array;
   if (size != size_ || shadow != shadowed_) {
     shadowed_ = shadow;
     size_ = size;
     ClearCache();
     if (shadowed_) {
       shadow_.reset(new int8[size]);
-      memset(shadow_.get(), 0, size);
+      if (!data) {
+        memset(shadow_.get(), 0, size);
+      }
+    } else {
+      shadow_.reset();
     }
   }
+  if (shadowed_ && data) {
+    memcpy(shadow_.get(), data, size);
+  }
 }
 
 bool Buffer::CheckRange(
@@ -218,13 +232,16 @@ bool BufferManager::GetClientId(GLuint service_id, GLuint* client_id) const {
 }
 
 void BufferManager::SetInfo(
-    Buffer* info, GLsizeiptr size, GLenum usage) {
+    Buffer* info, GLsizeiptr size, GLenum usage, const GLvoid* data) {
   DCHECK(info);
   memory_tracker_->TrackMemFree(info->size());
-  info->SetInfo(size,
-                usage,
-                info->target() == GL_ELEMENT_ARRAY_BUFFER ||
-                allow_buffers_on_multiple_targets_);
+  bool is_client_side_array =
+      (usage == GL_STREAM_DRAW &&
+       feature_info_->workarounds().use_client_side_arrays_for_stream_buffers);
+  bool shadow = info->target() == GL_ELEMENT_ARRAY_BUFFER ||
+                allow_buffers_on_multiple_targets_ ||
+                is_client_side_array;
+  info->SetInfo(size, usage, shadow, data, is_client_side_array);
   memory_tracker_->TrackMemAlloc(info->size());
 }