Merge 199131 "Fix maximum value index caching"

> Fix maximum value index caching
> 
> If a GL_ELEMENT_ARRAY_BUFFER is reloaded with new data such that the
> size does not change, the maximum value index cache is not properly
> invalidated, leading to subsequent errors validating the size of
> attribute arrays.
> 
> A one line fix, with additional unit test coverage.
> 
> TEST=Unit Test
> BUG=237874
> 
> Review URL: https://chromiumcodereview.appspot.com/14932002

TBR=lpique@chromium.org

Review URL: https://codereview.chromium.org/15692017

git-svn-id: svn://svn.chromium.org/chrome/branches/1500/src@202683 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 34 insertions, 1 deletions

diff --git a/gpu/command_buffer/service/buffer_manager.cc b/gpu/command_buffer/service/buffer_manager.cc
index 7fe9d20..298b78b 100644
--- a/gpu/command_buffer/service/buffer_manager.cc
+++ b/gpu/command_buffer/service/buffer_manager.cc
@@ -99,10 +99,10 @@ void Buffer::SetInfo(
     bool is_client_side_array) {
   usage_ = usage;
   is_client_side_array_ = is_client_side_array;
+  ClearCache();
   if (size != size_ || shadow != shadowed_) {
     shadowed_ = shadow;
     size_ = size;
-    ClearCache();
     if (shadowed_) {
       shadow_.reset(new int8[size]);
     } else {
diff --git a/gpu/command_buffer/service/buffer_manager_unittest.cc b/gpu/command_buffer/service/buffer_manager_unittest.cc
index f2ada75..72c9175 100644
--- a/gpu/command_buffer/service/buffer_manager_unittest.cc
+++ b/gpu/command_buffer/service/buffer_manager_unittest.cc
@@ -388,6 +388,39 @@ TEST_F(BufferManagerClientSideArraysTest, StreamBuffersAreShadowed) {
   EXPECT_FALSE(buffer->IsClientSideArray());
 }
 
+TEST_F(BufferManagerTest, MaxValueCacheClearedCorrectly) {
+  const GLuint kClientBufferId = 1;
+  const GLuint kServiceBufferId = 11;
+  const uint32 data1[] = {10, 9, 8, 7, 6, 5, 4, 3, 2, 1};
+  const uint32 data2[] = {11, 12, 13, 14, 15, 16, 17, 18, 19, 20};
+  const uint32 data3[] = {30, 29, 28};
+  manager_->CreateBuffer(kClientBufferId, kServiceBufferId);
+  Buffer* buffer = manager_->GetBuffer(kClientBufferId);
+  ASSERT_TRUE(buffer != NULL);
+  manager_->SetTarget(buffer, GL_ELEMENT_ARRAY_BUFFER);
+  GLuint max_value;
+  // Load the buffer with some initial data, and then get the maximum value for
+  // a range, which has the side effect of caching it.
+  DoBufferData(buffer, sizeof(data1), GL_STATIC_DRAW, data1, GL_NO_ERROR);
+  EXPECT_TRUE(
+      buffer->GetMaxValueForRange(0, 10, GL_UNSIGNED_INT, &max_value));
+  EXPECT_EQ(10u, max_value);
+  // Check that any cached values are invalidated if the buffer is reloaded
+  // with the same amount of data (but different content)
+  ASSERT_EQ(sizeof(data2), sizeof(data1));
+  DoBufferData(buffer, sizeof(data2), GL_STATIC_DRAW, data2, GL_NO_ERROR);
+  EXPECT_TRUE(
+      buffer->GetMaxValueForRange(0, 10, GL_UNSIGNED_INT, &max_value));
+  EXPECT_EQ(20u, max_value);
+  // Check that any cached values are invalidated if the buffer is reloaded
+  // with entirely different content.
+  ASSERT_NE(sizeof(data3), sizeof(data1));
+  DoBufferData(buffer, sizeof(data3), GL_STATIC_DRAW, data3, GL_NO_ERROR);
+  EXPECT_TRUE(
+      buffer->GetMaxValueForRange(0, 3, GL_UNSIGNED_INT, &max_value));
+  EXPECT_EQ(30u, max_value);
+}
+
 }  // namespace gles2
 }  // namespace gpu