[build] Switch sanitizer coverage bot to gn

This adds GN configs for using sanitizer coverage and refactors gcov
configs. Now, both coverage kinds are behind the same gn argument
v8_code_coverage.

This also switches the bot to GN.

Bug: chromium:645890,v8:5502
Change-Id: I3af606e0cad109dd790a121d0d92e53cf4e38f9a
Reviewed-on: https://chromium-review.googlesource.com/549360
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46254}

BUILD.gn

@@ -21,9 +21,6 @@ declare_args() {
   # Print to stdout on Android.
   v8_android_log_stdout = false
 
-  # Set flags for tracking code coverage with gcov. Requires is_clang=false.
-  v8_code_coverage = false
-
   # Sets -DV8_ENABLE_FUTURE.
   v8_enable_future = false
 
@@ -513,23 +510,15 @@ config("toolchain") {
 
 # Configs for code coverage with gcov. Separate configs for cflags and ldflags
 # to selectively influde cflags in non-test targets only.
-config("v8_code_coverage_cflags") {
-  # Make sure we're using gcc toolchain.
-  if (v8_code_coverage) {
-    assert(!is_clang)
-    cflags = [
-      "-fprofile-arcs",
-      "-ftest-coverage",
-    ]
-  }
+config("v8_gcov_coverage_cflags") {
+  cflags = [
+    "-fprofile-arcs",
+    "-ftest-coverage",
+  ]
 }
 
-config("v8_code_coverage_ldflags") {
-  # Make sure we're using gcc toolchain.
-  if (v8_code_coverage) {
-    assert(!is_clang)
-    ldflags = [ "-fprofile-arcs" ]
-  }
+config("v8_gcov_coverage_ldflags") {
+  ldflags = [ "-fprofile-arcs" ]
 }
 
 ###############################################################################

gni/isolate.gni

@@ -56,6 +56,11 @@ template("v8_isolate_run") {
       }
 
       # Translate gn to gyp variables.
+      if (v8_code_coverage) {
+        coverage = "1"
+      } else {
+        coverage = "0"
+      }
       if (is_asan) {
         asan = "1"
       } else {
@@ -157,9 +162,9 @@ template("v8_isolate_run") {
         "--config-variable",
         "tsan=$tsan",
         "--config-variable",
-        "coverage=0",
+        "coverage=$coverage",
         "--config-variable",
-        "sanitizer_coverage=0",
+        "sanitizer_coverage=$sanitizer_coverage_flags",
         "--config-variable",
         "component=$component",
         "--config-variable",

gni/v8.gni

@@ -7,6 +7,10 @@ import("//build/config/v8_target_cpu.gni")
 import("//build/split_static_library.gni")
 
 declare_args() {
+  # Set flags for tracking code coverage. Uses gcov with gcc and sanitizer
+  # coverage with clang.
+  v8_code_coverage = false
+
   # Includes files needed for correctness fuzzing.
   v8_correctness_fuzzer = false
 
@@ -68,7 +72,6 @@ v8_remove_configs = []
 v8_add_configs = [
   v8_path_prefix + ":features",
   v8_path_prefix + ":toolchain",
-  v8_path_prefix + ":v8_code_coverage_ldflags",
 ]
 
 if (is_debug && !v8_optimized_debug) {
@@ -86,6 +89,13 @@ if (is_debug && !v8_optimized_debug) {
   }
 }
 
+if (v8_code_coverage && !is_clang) {
+  v8_add_configs += [
+    v8_path_prefix + ":v8_gcov_coverage_cflags",
+    v8_path_prefix + ":v8_gcov_coverage_ldflags",
+  ]
+}
+
 if (is_posix && v8_enable_backtrace) {
   v8_remove_configs += [ "//build/config/gcc:symbol_visibility_hidden" ]
   v8_add_configs += [ "//build/config/gcc:symbol_visibility_default" ]
@@ -106,7 +116,6 @@ template("v8_source_set") {
     configs += invoker.configs
     configs -= v8_remove_configs
     configs += v8_add_configs
-    configs += [ v8_path_prefix + ":v8_code_coverage_cflags" ]
   }
 }
 
@@ -116,7 +125,6 @@ template("v8_header_set") {
     configs += invoker.configs
     configs -= v8_remove_configs
     configs += v8_add_configs
-    configs += [ v8_path_prefix + ":v8_code_coverage_cflags" ]
   }
 }
 
@@ -138,10 +146,15 @@ template("v8_executable") {
       # For enabling ASLR.
       ldflags = [ "-pie" ]
     }
-    if (!defined(testonly) || !testonly) {
+    if (defined(testonly) && testonly && v8_code_coverage) {
       # Only add code coverage cflags for non-test files for performance
       # reasons.
-      configs += [ v8_path_prefix + ":v8_code_coverage_cflags" ]
+      if (is_clang) {
+        configs -= [ "//build/config/sanitizers:default_sanitizer_flags" ]
+        configs += [ "//build/config/sanitizers:default_sanitizer_flags_but_coverage" ]
+      } else {
+        configs -= [ v8_path_prefix + ":v8_gcov_coverage_cflags" ]
+      }
     }
   }
 }
@@ -152,6 +165,5 @@ template("v8_component") {
     configs += invoker.configs
     configs -= v8_remove_configs
     configs += v8_add_configs
-    configs += [ v8_path_prefix + ":v8_code_coverage_cflags" ]
   }
 }

infra/mb/mb_config.pyl

@@ -195,7 +195,7 @@
       'v8_linux64_asan_rel_ng': 'gn_release_x64_asan_minimal_symbols',
       'v8_linux64_msan_rel': 'gn_release_simulate_arm64_msan_minimal_symbols',
       'v8_linux64_sanitizer_coverage_rel':
-          'gyp_release_x64_asan_minimal_symbols_coverage',
+          'gn_release_x64_asan_minimal_symbols_coverage',
       'v8_linux64_tsan_rel': 'gn_release_x64_tsan_minimal_symbols',
       'v8_linux64_tsan_concurrent_marking_rel_ng':
           'gn_release_x64_tsan_concurrent_marking_minimal_symbols',
@@ -368,6 +368,9 @@
     'gn_release_x64_asan_minimal_symbols': [
       'gn', 'release_bot', 'x64', 'asan', 'lsan', 'minimal_symbols',
       'swarming'],
+    'gn_release_x64_asan_minimal_symbols_coverage': [
+      'gn', 'release_bot', 'x64', 'asan', 'bb', 'coverage', 'lsan',
+      'minimal_symbols', 'swarming'],
     'gn_release_x64_asan_no_lsan': [
       'gn', 'release_bot', 'x64', 'asan', 'swarming'],
     'gn_release_x64_asan_symbolized_edge_verify_heap': [
@@ -496,9 +499,6 @@
     # Gyp release configs for x64.
     'gyp_release_x64': [
       'gyp', 'release_bot', 'x64', 'swarming'],
-    'gyp_release_x64_asan_minimal_symbols_coverage': [
-      'gyp', 'release_bot', 'x64', 'asan', 'bb', 'coverage', 'lsan',
-      'minimal_symbols', 'swarming'],
     'gyp_release_x64_gcc_coverage': [
       'gyp', 'release_bot', 'x64', 'coverage', 'gcc'],