commit c80c7ae3fb274e61373ae9cd8081e8e0723c6cde
author Cody Northrop <cnorthrop@google.com> Thu Feb 24 10:43:15 2022 -0700
committer Angle LUCI CQ <angle-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Mar 01 00:03:37 2022 +0000
tree 5f11ec3557546cd5c5de0c57617ee3185c37af8e
parent cfe5a1735a934cc83133bb6c69d19aa27278a270

Capture/Replay: Merge Deletes in Reset

Before this CL, when regenning resources, we would iterate through
each resource ID and issue a delete followed by a gen. The delete
is required to get resources back to their original state, often
caused by applications recreating them during the run.

This ran into problems when our resource maps had stale data in them,
i.e. a texture that had been deleted by the app but remained in our
gTextureMap. We could inadvertently delete a resource we had just
genned.

For example, in ResetReplay(), say we have two textures to delete:

    // gTextureMap[1] start with 5
    const GLuint glDeleteTextures_texturesPacked_1[] =
        { gTextureMap[1] };
    glDeleteTextures(1, glDeleteTextures_texturesPacked_1);
    // We just deleted texture 5, now create a new one
    glGenTextures(1, reinterpret_cast<GLuint *>(gReadBuffer));
    // The driver returned 15, which was unused at this time
    UpdateTextureID(1, 0);
    // gTextureMap[1] now contains 15
    ...
    // gTextureMap[2] happens to start with 15, which was in use in
    // the trace, but was deleted and is no longer in use. The
    // deleted value is not cleared from gTextureMap (which is
    // another possible way to solve this).
    const GLuint glDeleteTextures_texturesPacked_2[] =
        { gTextureMap[2] };
    glDeleteTextures(1, glDeleteTextures_texturesPacked_2);
    // Whoops! We just deleted our brand new texture 15, even though
    // it no longer maps to the original texture.
    glGenTextures(1, reinterpret_cast<GLuint *>(gReadBuffer));
    UpdateTextureID(2, 0);
    // Now gTextureMap[2] contains whatever came back from the driver
    ...
    // The first use of gTextureMap[1] will fail on loop because
    // texture 15 no longer exists!

To avoid this problem we delete all resources up front before
genning any new ones.

  const GLuint deleteTextures[] = {gTextureMap[1], gTextureMap[2]};
  glDeleteTextures(2, deleteTextures);
  // Now we no longer have any deletes in the create sequence
  glGenTextures(1, reinterpret_cast<GLuint *>(gReadBuffer));
  UpdateTextureID(1, 0);
  glGenTextures(1, reinterpret_cast<GLuint *>(gReadBuffer));
  UpdateTextureID(2, 0);

This is applied to all the resources we regen right now.

This CL:
* Merges the deletion of new resources (that didn't exist when the
  trace starts) with resources that are being regenned. That means
  there is just one big delete.
* Removes Delete from the call sequences we track for each resource
  since we no longer need to keep them around.
* Adds a formatting helper to avoid code duplication.

Test: Blade&Soul Revolution MEC (UE4)
Bug: angleproject:4599
Bug: angleproject:7053
Change-Id: Ida3b7e1ad5d94c5e9860447d5cf959278f37ad47
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3492849
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Gert Wollny <gert.wollny@collabora.com>
Commit-Queue: Cody Northrop <cnorthrop@google.com>