[sksl] Make sksl tracing optional

This removes the required dependency on our JSON code. In the Bazel
rules, this dependency is pushed down into sksl instead of required
by the cc_binary rules.

It adds a stub version of SkVMDebugTrace.cpp and removes
SkVMDebugTracePlayer unless the appropriate GN or Bazel flag
is set (skia_enable_sksl_tracing and enable_sksl_tracing,
respectively). There was an existing #define that CanvasKit
used (CK_INCLUDE_SKSL_TRACE) and this was changed to
SKSL_ENABLE_TRACING.

Users of //:skia_core no longer need to specify a JSON dep,
if sksl needs it (e.g. for tracing), then it will specify
the dependency.

This is a reland of https://skia-review.googlesource.com/c/skia/+/528837

Bug: skia:12541
Change-Id: I79612c69fdbefd3db9822a2b66df7552f7c13865
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/529278
Reviewed-by: John Stiles <johnstiles@google.com>

.bazelrc

@@ -24,6 +24,8 @@ build --flag_alias=disable_effect_serialization=no//bazel/common_config_settings
 build --flag_alias=enable_effect_serialization=//bazel/common_config_settings:enable_effect_serialization
 build --flag_alias=disable_skslc=no//bazel/common_config_settings:enable_skslc
 build --flag_alias=enable_skslc=//bazel/common_config_settings:enable_skslc
+build --flag_alias=disable_sksl_tracing=no//bazel/common_config_settings:enable_sksl_tracing
+build --flag_alias=enable_sksl_tracing=//bazel/common_config_settings:enable_sksl_tracing
 build --flag_alias=disable_tracing=no//bazel/common_config_settings:enable_tracing
 build --flag_alias=enable_tracing=//bazel/common_config_settings:enable_tracing
 build --flag_alias=disable_vma=no//bazel/common_config_settings:use_vulkan_memory_allocator

BUILD.gn

@@ -711,6 +711,7 @@ if (skia_compile_sksl_tests) {
   # Build skslc.
   skia_executable("skslc") {
     defines = [
+      "SKSL_ENABLE_TRACING",
       "SKSL_STANDALONE",
       "SK_DISABLE_TRACING",
       "SK_ENABLE_SPIRV_CROSS",
@@ -727,6 +728,7 @@ if (skia_compile_sksl_tests) {
     }
     sources += skia_sksl_sources
     sources += skia_sksl_gpu_sources
+    sources += skia_sksl_tracing_sources
     include_dirs = [ "." ]
     deps = [
       ":run_sksllex",
@@ -1381,6 +1383,11 @@ skia_component("skia") {
   if (skia_enable_sksl) {
     deps += [ ":dehydrate_sksl" ]
     sources += skia_sksl_sources
+
+    if (skia_enable_sksl_tracing) {
+      defines += [ "SKSL_ENABLE_TRACING" ]
+      sources += skia_sksl_tracing_sources
+    }
   }
 
   if (skia_build_for_debugger) {

bazel/BUILD.bazel

@@ -33,6 +33,11 @@ GENERAL_DEFINES = [
         "SK_ENABLE_SPIRV_VALIDATION",
     ],
     "//conditions:default": [],
+}) + select({
+    "//bazel/common_config_settings:enable_sksl_tracing_true": [
+        "SKSL_ENABLE_TRACING",
+    ],
+    "//conditions:default": [],
 })
 
 GPU_DEFINES = select({

bazel/cc_binary_with_flags.bzl

@@ -7,6 +7,7 @@ It is based off of https://github.com/bazelbuild/examples/tree/main/rules/starla
 """
 
 _bool_flags = [
+    "//bazel/common_config_settings:enable_sksl_tracing",
     "//bazel/common_config_settings:enable_skslc",
     "//bazel/common_config_settings:is_skia_dev_build",
     "//bazel/common_config_settings:use_icu",

bazel/common_config_settings/BUILD.bazel

@@ -192,6 +192,11 @@ bool_flag(
     flag_name = "enable_skslc",
 )
 
+bool_flag(
+    default = False,
+    flag_name = "enable_sksl_tracing",
+)
+
 bool_flag(
     # See SkTraceVentCommon.h for more on this type of tracing.
     default = True,

example/BUILD.bazel

@@ -23,7 +23,6 @@ cc_binary_with_flags(
     },
     deps = [
         "//:skia_core",
-        "//src/utils:json_srcs",
         "//tools/sk_app",
     ],
 )
@@ -46,7 +45,6 @@ cc_binary_with_flags(
     },
     deps = [
         "//:skia_core",
-        "//src/utils:json_srcs",
         "//tools/sk_app",
     ],
 )
@@ -69,7 +67,6 @@ cc_binary_with_flags(
     },
     deps = [
         "//:skia_core",
-        "//src/utils:json_srcs",
         "//tools/sk_app",
     ],
 )
@@ -87,7 +84,6 @@ cc_binary_with_flags(
     },
     deps = [
         "//:skia_core",
-        "//src/utils:json_srcs",
         # This DEPS is for the utility in the demo for creating a vulkan context.
         # Outside clients would not need it.
         "//tools/gpu/vk:VkTestUtils_src",

gn/gn_to_bp.py

@@ -495,6 +495,8 @@ def generate_args(target_os, enable_gpu, renderengine = False):
 
     'skia_use_fontconfig':                  'false',
     'skia_include_multiframe_procs':        'false',
+    # Required for some SKSL tests
+    'skia_enable_sksl_tracing':             'true',
   }
   d['target_os'] = target_os
   if target_os == '"android"':

gn/skia.gni

@@ -25,6 +25,7 @@ declare_args() {
   skia_enable_skottie = !(is_win && is_component_build) ||
                         (is_wasm && skia_canvaskit_enable_skottie)
   skia_enable_sksl = true
+  skia_enable_sksl_tracing = is_skia_dev_build
   skia_enable_skvm_jit_when_possible = is_skia_dev_build
   skia_enable_svg = !is_component_build
   skia_enable_tools = is_skia_dev_build

gn/skqp_gn_args.py

@@ -9,11 +9,12 @@ def GetGNArgs(api_level, debug, arch=None, ndk=None, is_android_bp=False):
         'skia_enable_fontmgr_android':      'false',
         'skia_enable_fontmgr_empty':        'true',
         'skia_enable_pdf':                  'false',
-        'skia_enable_skshaper':             'false',
         'skia_enable_skottie':              'false',
+        'skia_enable_skshaper':             'false',
+        'skia_enable_sksl_tracing':         'true',
         'skia_enable_sktext':               'false',
-        'skia_enable_tools':                'true',
         'skia_enable_svg':                  'false',
+        'skia_enable_tools':                'true',
         'skia_tools_require_resources':     'true',
         'skia_use_dng_sdk':                 'false',
         'skia_use_expat':                   'true',

gn/sksl.gni

@@ -204,8 +204,6 @@ skia_sksl_sources = [
   "$_src/sksl/spirv.h",
   "$_src/sksl/tracing/SkVMDebugTrace.cpp",
   "$_src/sksl/tracing/SkVMDebugTrace.h",
-  "$_src/sksl/tracing/SkVMDebugTracePlayer.cpp",
-  "$_src/sksl/tracing/SkVMDebugTracePlayer.h",
   "$_src/sksl/transform/SkSLBuiltinVariableScanner.cpp",
   "$_src/sksl/transform/SkSLEliminateDeadFunctions.cpp",
   "$_src/sksl/transform/SkSLEliminateDeadGlobalVariables.cpp",
@@ -214,6 +212,11 @@ skia_sksl_sources = [
   "$_src/sksl/transform/SkSLTransform.h",
 ]
 
+skia_sksl_tracing_sources = [
+  "$_src/sksl/tracing/SkVMDebugTracePlayer.cpp",
+  "$_src/sksl/tracing/SkVMDebugTracePlayer.h",
+]
+
 skia_sksl_gpu_sources = [
   "$_src/sksl/codegen/SkSLCodeGenerator.h",
   "$_src/sksl/codegen/SkSLGLSLCodeGenerator.cpp",

modules/canvaskit/BUILD.bazel

@@ -138,9 +138,6 @@ CK_DEFINES = [
 }) + select({
     ":enable_runtime_effect_true": ["CK_INCLUDE_RUNTIME_EFFECT=1"],
     ":enable_runtime_effect_false": [],
-}) + select({
-    ":enable_sksl_tracing_true": ["CK_INCLUDE_SKSL_TRACE=1"],
-    ":enable_sksl_tracing_false": [],
 })
 
 CK_RELEASE_OPTS = [
@@ -351,6 +348,9 @@ cc_binary_with_flags(
         "use_icu": [
             "True",
         ],
+        "enable_sksl_tracing": [
+            "True",
+        ],
         "shaper_backend": [
             "harfbuzz_shaper",
         ],
@@ -421,11 +421,6 @@ bool_flag(
     flag_name = "enable_runtime_effect",
 )
 
-bool_flag(
-    default = True,
-    flag_name = "enable_sksl_tracing",
-)
-
 bool_flag(
     default = True,
     flag_name = "include_matrix_js",

modules/canvaskit/BUILD.gn

@@ -369,9 +369,6 @@ skia_wasm_lib("canvaskit") {
   if (skia_canvaskit_enable_rt_shader) {
     defines += [ "CK_INCLUDE_RUNTIME_EFFECT" ]
   }
-  if (skia_canvaskit_enable_sksl_trace) {
-    defines += [ "CK_INCLUDE_SKSL_TRACE" ]
-  }
   if (!skia_canvaskit_enable_alias_font) {
     defines += [ "CANVASKIT_NO_ALIAS_FONT" ]
   }
@@ -382,4 +379,7 @@ skia_wasm_lib("canvaskit") {
   if (!skia_canvaskit_enable_font) {
     defines += [ "CK_NO_FONTS" ]
   }
+  if (skia_enable_sksl_tracing) {
+    defines += [ "SKSL_ENABLE_TRACING" ]
+  }
 }

modules/canvaskit/canvaskit_bindings.cpp

@@ -89,7 +89,7 @@
 #include "include/pathops/SkPathOps.h"
 #endif
 
-#if defined(CK_INCLUDE_RUNTIME_EFFECT) && defined(CK_INCLUDE_SKSL_TRACE)
+#if defined(CK_INCLUDE_RUNTIME_EFFECT) && defined(SKSL_ENABLE_TRACING)
 #include "include/sksl/SkSLDebugTrace.h"
 #endif
 
@@ -1802,7 +1802,7 @@ EMSCRIPTEN_BINDINGS(Skia) {
         }), allow_raw_pointers());
 
 #ifdef CK_INCLUDE_RUNTIME_EFFECT
-#ifdef CK_INCLUDE_SKSL_TRACE
+#ifdef SKSL_ENABLE_TRACING
     class_<SkSL::DebugTrace>("DebugTrace")
         .smart_ptr<sk_sp<SkSL::DebugTrace>>("sk_sp<DebugTrace>")
         .function("writeTrace", optional_override([](SkSL::DebugTrace& self) -> std::string {
@@ -1830,7 +1830,7 @@ EMSCRIPTEN_BINDINGS(Skia) {
             }
             return effect;
         }))
-#ifdef CK_INCLUDE_SKSL_TRACE
+#ifdef SKSL_ENABLE_TRACING
         .class_function("MakeTraced", optional_override([](
                 sk_sp<SkShader> shader,
                 int traceCoordX,

modules/canvaskit/compile.sh

@@ -230,6 +230,7 @@ echo "Compiling"
   skia_use_zlib=true \
   skia_enable_gpu=${ENABLE_GPU} \
   skia_build_for_debugger=${DEBUGGER_ENABLED} \
+  skia_enable_sksl_tracing=${ENABLE_SKSL_TRACE} \
   \
   ${GN_SHAPER} \
   ${GN_FONT} \
@@ -247,7 +248,6 @@ echo "Compiling"
   skia_canvaskit_enable_particles=${ENABLE_PARTICLES} \
   skia_canvaskit_enable_pathops=${ENABLE_PATHOPS} \
   skia_canvaskit_enable_rt_shader=${ENABLE_RT_SHADER} \
-  skia_canvaskit_enable_sksl_trace=${ENABLE_SKSL_TRACE} \
   skia_canvaskit_enable_matrix_helper=${ENABLE_MATRIX} \
   skia_canvaskit_enable_canvas_bindings=${ENABLE_CANVAS} \
   skia_canvaskit_enable_font=${ENABLE_FONT} \

src/sksl/BUILD.bazel

@@ -15,8 +15,7 @@ filegroup(
 )
 
 cc_library(
-    name = "srcs",
-    visibility = ["//:__subpackages__"],
+    name = "core_srcs",
     deps = [
         ":SkSLAnalysis_src",
         ":SkSLBuiltinMap_src",
@@ -149,6 +148,23 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "tracing_srcs",
+    deps = [
+        "//src/sksl/tracing:SkVMDebugTracePlayer_src",
+        "//src/utils:json_srcs",
+    ],
+)
+
+cc_library(
+    name = "srcs",
+    visibility = ["//:__subpackages__"],
+    deps = [":core_srcs"] + select({
+        "//bazel/common_config_settings:enable_sksl_tracing_true": [":tracing_srcs"],
+        "//bazel/common_config_settings:enable_sksl_tracing_false": [],
+    }),
+)
+
 generated_cc_atom(
     name = "GLSL.std.450_hdr",
     hdrs = ["GLSL.std.450.h"],

src/sksl/tracing/SkVMDebugTrace.cpp

@@ -7,6 +7,8 @@
 
 #include "src/sksl/tracing/SkVMDebugTrace.h"
 
+#ifdef SKSL_ENABLE_TRACING
+
 #include "include/core/SkData.h"
 #include "include/core/SkRefCnt.h"
 #include "include/core/SkStream.h"
@@ -386,3 +388,28 @@ bool SkVMDebugTrace::readTrace(SkStream* r) {
 }
 
 }  // namespace SkSL
+
+#else // SKSL_ENABLE_TRACING
+
+#include <string>
+
+namespace SkSL {
+    void SkVMDebugTrace::setTraceCoord(const SkIPoint &coord) {}
+
+    void SkVMDebugTrace::setSource(std::string source) {}
+
+    bool SkVMDebugTrace::readTrace(SkStream *r) { return false; }
+
+    void SkVMDebugTrace::writeTrace(SkWStream *w) const {}
+
+    void SkVMDebugTrace::dump(SkWStream *o) const {}
+
+    std::string SkVMDebugTrace::getSlotComponentSuffix(int slotIndex) const { return ""; }
+
+    std::string SkVMDebugTrace::getSlotValue(int slotIndex, int32_t value) const { return ""; }
+
+    double SkVMDebugTrace::interpretValueBits(int slotIndex, int32_t valueBits) const { return 0; }
+
+    std::string SkVMDebugTrace::slotValueToString(int slotIndex, double value) const { return ""; }
+}
+#endif