FrameCapture: Support glProgramBinary

This CL allows applications to use glProgramBinary. Normally this is
a problem because we need program source in order to recreate shaders
in use during mid-execution capture. Use of program binaries
means an app can start and render frames without having submitted
source for that run.

To support this, we will embed program source into ANGLE's binary
format. This will allow us to extract it when the app submits the
binary. We will only embed this when capture is enabled to prevent
increased binary size in the common case. Since this changes ANGLE's
binary format, apps will recreate binaries when capture is enabled.

Additionally, we can't allow captures to have glProgramBinary calls
in the middle of captured frame ranges, so intercept those calls and
replace with a full linking sequence.

Changes include:

- Add new frontend feauture enableProgramBinaryForCapture that allows
  OES_get_program_binary during capture.
- Update ANGLE's binary format to include program source when
  capture is enabled.
- Update maybeOverrideEntryPoint to handle multiple new calls
  instead of a single call.
- Override calls to glProgramBinary that occur mid-capture
  to instead emit a full GenerateLinkedProgram sequence.
- Add checks for created/attached shaders during FrameCapture since
  they won't be available for programs populated by the app using
  glProgramBinary.

Test: Fortnite MEC
Bug: b/180418810
Bug: angleproject:5658
Change-Id: Ib2a0e9e434d3ee0f384d128c48b2a7d4834f5b0f
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3105390
Commit-Queue: Cody Northrop <cnorthrop@google.com>
Reviewed-by: Tim Van Patten <timvp@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/platform/FrontendFeatures.h b/include/platform/FrontendFeatures.h
index aee4fbffee..fad72d9c6f 100644
--- a/include/platform/FrontendFeatures.h
+++ b/include/platform/FrontendFeatures.h
@@ -87,6 +87,11 @@ struct FrontendFeatures : angle::FeatureSetBase
     angle::Feature forceInitShaderOutputVariables = {
         "forceInitShaderOutputVariables", angle::FeatureCategory::FrontendFeatures,
         "Force-enable shader output variable initialization", &members};
+
+    angle::Feature enableProgramBinaryForCapture = {
+        "enableProgramBinaryForCapture", angle::FeatureCategory::FrontendFeatures,
+        "Even if FrameCapture is enabled, enable GL_OES_get_program_binary", &members,
+        "http://anglebug.com/5658"};
 };
 
 inline FrontendFeatures::FrontendFeatures()  = default;