Add stub gpu workaround generators

Like https://chromium-review.googlesource.com/c/chromium/src/+/1005362,
this patch adds a way for Chrome and Skia to share a set of driver
workaround names so that they can be turned on by Chrome (or Skia) as
needed.

To avoid weird cross-repository dependencies, the generator script is
duplicated in Skia.

This patch just adds a few dummy workaround names to make sure the build
process is working.  The followup to this is to add workaround init
to GrContext/GrContextOptions and to start implementing individual
workarounds.

Implementing these workarounds is to support Chrome's "out of process
raster" which will use Ganesh without a command buffer, and so will not
have the workarounds that the command buffer provides.

Bug: chromium:829614
Change-Id: I40745a777a95805995991fedb81657ae418b52d9
Reviewed-on: https://skia-review.googlesource.com/120608
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Adrienne Walker <enne@chromium.org>

4 files changed, 92 insertions, 0 deletions

diff --git a/src/gpu/GrDriverBugWorkarounds.cpp b/src/gpu/GrDriverBugWorkarounds.cpp
new file mode 100644
index 0000000000..5ed9d8d2ef
--- /dev/null
+++ b/src/gpu/GrDriverBugWorkarounds.cpp
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "GrDriverBugWorkarounds.h"
+
+#include "SkTypes.h"
+
+GrDriverBugWorkarounds::GrDriverBugWorkarounds() = default;
+
+GrDriverBugWorkarounds::GrDriverBugWorkarounds(
+        const std::vector<int>& enabled_driver_bug_workarounds) {
+    for (auto id : enabled_driver_bug_workarounds) {
+        switch (id) {
+#define GPU_OP(type, name)                        \
+            case GrDriverBugWorkaroundType::type: \
+                name = true;                      \
+                break;
+
+            GPU_DRIVER_BUG_WORKAROUNDS(GPU_OP)
+#undef GPU_OP
+            default:
+                SK_ABORT("Not implemented");
+                break;
+        }
+    }
+}
+
+GrDriverBugWorkarounds::~GrDriverBugWorkarounds() = default;
diff --git a/src/gpu/GrDriverBugWorkarounds.h b/src/gpu/GrDriverBugWorkarounds.h
new file mode 100644
index 0000000000..bca5dc99f1
--- /dev/null
+++ b/src/gpu/GrDriverBugWorkarounds.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrDriverBugWorkarounds_DEFINED
+#define GrDriverBugWorkarounds_DEFINED
+
+// External embedders of Skia can override this to use their own list
+// of workaround names.
+#ifdef SK_GPU_WORKAROUNDS_HEADER
+#include SK_GPU_WORKAROUNDS_HEADER
+#else
+// To regenerate this file, set gn arg "skia_generate_workarounds = true".
+// This is not rebuilt by default to avoid embedders having to have extra
+// build steps.
+#include "GrDriverBugWorkaroundsAutogen.h"
+#endif
+
+#include <stdint.h>
+#include <vector>
+
+enum GrDriverBugWorkaroundType {
+#define GPU_OP(type, name) type,
+  GPU_DRIVER_BUG_WORKAROUNDS(GPU_OP)
+#undef GPU_OP
+  NUMBER_OF_GPU_DRIVER_BUG_WORKAROUND_TYPES
+};
+
+class GrDriverBugWorkarounds {
+ public:
+  GrDriverBugWorkarounds();
+  explicit GrDriverBugWorkarounds(const std::vector<int32_t>& workarounds);
+
+  ~GrDriverBugWorkarounds();
+
+#define GPU_OP(type, name) bool name = false;
+  GPU_DRIVER_BUG_WORKAROUNDS(GPU_OP)
+#undef GPU_OP
+};
+
+#endif
diff --git a/src/gpu/GrDriverBugWorkaroundsAutogen.h b/src/gpu/GrDriverBugWorkaroundsAutogen.h
new file mode 100644
index 0000000000..4ff99bb98c
--- /dev/null
+++ b/src/gpu/GrDriverBugWorkaroundsAutogen.h
@@ -0,0 +1,14 @@
+// Copyright 2018 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.
+
+// This file is auto-generated from
+//    ../../tools/build_workaround_header.py
+// DO NOT EDIT!
+
+#define GPU_DRIVER_BUG_WORKAROUNDS(GPU_OP)\
+  GPU_OP(AVOID_STENCIL_BUFFERS,       \
+         avoid_stencil_buffers)       \
+  GPU_OP(CLEAR_TO_ZERO_OR_ONE_BROKEN, \
+         clear_to_zero_or_one_broken) \
+// The End
diff --git a/src/gpu/gpu_workaround_list.txt b/src/gpu/gpu_workaround_list.txt
new file mode 100644
index 0000000000..89a7231e9c
--- /dev/null
+++ b/src/gpu/gpu_workaround_list.txt
@@ -0,0 +1,2 @@
+avoid_stencil_buffers
+clear_to_zero_or_one_broken