[gn] Improve sharing common configuration

This moves common configs used by all v8 targets into
common templates.

This also fixes using v8_optimized_debug correctly in
executables and components.

BUG=chromium:474921
NOTRY=true

Review-Url: https://codereview.chromium.org/2054803003
Cr-Commit-Position: refs/heads/master@{#36956}

BUILD.gn

@@ -51,9 +51,6 @@ declare_args() {
   # Sets -dOBJECT_PRINT.
   v8_object_print = false
 
-  # Turns on compiler optimizations in V8 in Debug build.
-  v8_optimized_debug = true
-
   # With post mortem support enabled, metadata is embedded into libv8 that
   # describes various parameters of the VM for use by debuggers. See
   # tools/gen-postmortem-metadata.py for details.
@@ -302,33 +299,6 @@ config("toolchain") {
   }
 }
 
-###############################################################################
-# Templates
-#
-
-template("v8_source_set") {
-  source_set(target_name) {
-    forward_variables_from(invoker, "*", [ "configs" ])
-    configs += invoker.configs
-    configs -= [ "//build/config/compiler:chromium_code" ]
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-    configs += [
-      ":features",
-      ":toolchain",
-    ]
-
-    # TODO(machenbach): This config doesn't affect executables and components.
-    # It should be moved to a common place.
-    if (is_debug && !v8_optimized_debug) {
-      configs -= [ "//build/config/compiler:default_optimization" ]
-      configs += [ "//build/config/compiler:no_optimize" ]
-    } else {
-      configs -= [ "//build/config/compiler:default_optimization" ]
-      configs += [ "//build/config/compiler:optimize_max" ]
-    }
-  }
-}
-
 ###############################################################################
 # Actions
 #
@@ -2042,19 +2012,15 @@ v8_source_set("simple_fuzzer") {
 #
 
 if (current_toolchain == v8_snapshot_toolchain) {
-  executable("mksnapshot") {
+  v8_executable("mksnapshot") {
     visibility = [ ":*" ]  # Only targets in this file can depend on this.
 
     sources = [
       "src/snapshot/mksnapshot.cc",
     ]
 
-    configs -= [ "//build/config/compiler:chromium_code" ]
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-    configs += [
+    configs = [
       ":internal_config",
-      ":features",
-      ":toolchain",
     ]
 
     deps = [
@@ -2101,7 +2067,7 @@ group("gn_all") {
 }
 
 if (is_component_build) {
-  component("v8") {
+  v8_component("v8") {
     sources = [
       "src/v8dll-main.cc",
     ]
@@ -2111,12 +2077,8 @@ if (is_component_build) {
       ":v8_maybe_snapshot",
     ]
 
-    configs -= [ "//build/config/compiler:chromium_code" ]
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-    configs += [
+    configs = [
       ":internal_config",
-      ":features",
-      ":toolchain",
     ]
 
     public_configs = [ ":external_config" ]
@@ -2131,21 +2093,17 @@ if (is_component_build) {
   }
 }
 
-executable("d8") {
+v8_executable("d8") {
   sources = [
     "src/d8.cc",
     "src/d8.h",
   ]
 
-  configs -= [ "//build/config/compiler:chromium_code" ]
-  configs += [ "//build/config/compiler:no_chromium_code" ]
-  configs += [
+  configs = [
     # Note: don't use :internal_config here because this target will get
     # the :external_config applied to it by virtue of depending on :v8, and
     # you can't have both applied to the same target.
     ":internal_config_base",
-    ":features",
-    ":toolchain",
   ]
 
   deps = [
@@ -2181,20 +2139,16 @@ v8_isolate_run("d8") {
 }
 
 if (want_v8_shell) {
-  executable("v8_shell") {
+  v8_executable("v8_shell") {
     sources = [
       "samples/shell.cc",
     ]
 
-    configs -= [ "//build/config/compiler:chromium_code" ]
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-    configs += [
+    configs = [
       # Note: don't use :internal_config here because this target will get
       # the :external_config applied to it by virtue of depending on :v8, and
       # you can't have both applied to the same target.
       ":internal_config_base",
-      ":features",
-      ":toolchain",
     ]
 
     deps = [
@@ -2213,14 +2167,14 @@ if (want_v8_shell) {
 template("v8_fuzzer") {
   name = target_name
   forward_variables_from(invoker, "*")
-  executable("v8_simple_" + name) {
+  v8_executable("v8_simple_" + name) {
     deps = [
       ":" + name,
       ":simple_fuzzer",
       "//build/win:default_exe_manifest",
     ]
 
-    configs += [ ":external_config" ]
+    configs = [ ":external_config" ]
   }
 }
 

gni/v8.gni

@@ -5,6 +5,9 @@
 import("//build/config/sanitizers/sanitizers.gni")
 
 declare_args() {
+  # Turns on compiler optimizations in V8 in Debug build.
+  v8_optimized_debug = true
+
   # Enable the snapshot feature, for fast context creation.
   # http://v8project.blogspot.com/2015/09/custom-startup-snapshots.html
   v8_use_snapshot = true
@@ -28,3 +31,56 @@ if (v8_target_arch == "") {
     v8_target_arch = target_cpu
   }
 }
+
+###############################################################################
+# Templates
+#
+
+# Points to // in v8 stand-alone or to //v8/ in chromium. We need absolute
+# paths for all configs in templates as they are shared in different
+# subdirectories.
+path_prefix = get_path_info("../", "abspath")
+
+# Common configs to remove or add in all v8 targets.
+remove_configs = [ "//build/config/compiler:chromium_code" ]
+add_configs = [
+  "//build/config/compiler:no_chromium_code",
+  path_prefix + ":features",
+  path_prefix + ":toolchain",
+]
+
+if (is_debug && !v8_optimized_debug) {
+  remove_configs += [ "//build/config/compiler:default_optimization" ]
+  add_configs += [ "//build/config/compiler:no_optimize" ]
+} else {
+  remove_configs += [ "//build/config/compiler:default_optimization" ]
+  add_configs += [ "//build/config/compiler:optimize_max" ]
+}
+
+# All templates should be kept in sync.
+template("v8_source_set") {
+  source_set(target_name) {
+    forward_variables_from(invoker, "*", [ "configs" ])
+    configs += invoker.configs
+    configs -= remove_configs
+    configs += add_configs
+  }
+}
+
+template("v8_executable") {
+  executable(target_name) {
+    forward_variables_from(invoker, "*", [ "configs" ])
+    configs += invoker.configs
+    configs -= remove_configs
+    configs += add_configs
+  }
+}
+
+template("v8_component") {
+  component(target_name) {
+    forward_variables_from(invoker, "*", [ "configs" ])
+    configs += invoker.configs
+    configs -= remove_configs
+    configs += add_configs
+  }
+}

test/cctest/BUILD.gn

@@ -6,7 +6,7 @@
 
 import("../../gni/v8.gni")
 
-executable("cctest") {
+v8_executable("cctest") {
   testonly = true
 
   sources = [
@@ -283,13 +283,9 @@ executable("cctest") {
     # },
   }
 
-  configs -= [ "//build/config/compiler:chromium_code" ]
-  configs += [ "//build/config/compiler:no_chromium_code" ]
-  configs += [
+  configs = [
     "../..:external_config",
     "../..:internal_config_base",
-    "../..:features",
-    "../..:toolchain",
   ]
 
   # TODO(machenbach): Translate from gyp.

test/unittests/BUILD.gn

@@ -6,7 +6,7 @@
 
 import("../../gni/v8.gni")
 
-executable("unittests") {
+v8_executable("unittests") {
   testonly = true
 
   sources = [
@@ -136,13 +136,9 @@ executable("unittests") {
     sources += [ "compiler/s390/instruction-selector-s390-unittest.cc" ]
   }
 
-  configs -= [ "//build/config/compiler:chromium_code" ]
-  configs += [ "//build/config/compiler:no_chromium_code" ]
-  configs += [
+  configs = [
     "../..:external_config",
     "../..:internal_config_base",
-    "../..:features",
-    "../..:toolchain",
   ]
 
   # TODO(machenbach): Translate from gyp.