# Copyright 2016 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.
import("//chromium/build/config/chromeos/ui_mode.gni")
import("//chromium/build/config/clang/clang.gni")
import("//chromium/build/config/compiler/compiler.gni")
import("//chromium/build/config/compiler/pgo/pgo.gni")
import("//chromium/build/toolchain/toolchain.gni")
# Configuration that enables PGO instrumentation.
config("pgo_instrumentation_flags") {
visibility = [ ":default_pgo_flags" ]
# Only add flags when chrome_pgo_phase == 1, so that variables we would use
# are not required to be defined when we're not actually using PGO.
if (chrome_pgo_phase == 1 && is_clang && !is_nacl && is_a_target_toolchain) {
cflags = [ "-fprofile-generate" ]
if (!is_win) {
# Windows directly calls link.exe instead of the compiler driver when
# linking, and embeds the path to the profile runtime library as
# dependent library into each object file.
ldflags = [ "-fprofile-generate" ]
}
}
}
# Configuration that enables optimization using profile data.
config("pgo_optimization_flags") {
visibility = [ ":default_pgo_flags" ]
# Only add flags when chrome_pgo_phase == 2, so that variables we would use
# are not required to be defined when we're not actually using PGO.
if (chrome_pgo_phase == 2 && is_clang && !is_nacl && is_a_target_toolchain) {
_pgo_target = ""
# There are txt files used by //tools/update_pgo_profiles.py to decide which
# profiles to use, adding them as inputs so that analyzer recognizes the
# dependencies.
inputs = []
if (is_win) {
if (target_cpu == "x64") {
_pgo_target = "win64"
inputs = [ "//chrome/build/win64.pgo.txt" ]
} else {
_pgo_target = "win32"
inputs = [ "//chrome/build/win32.pgo.txt" ]
}
} else if (is_mac) {
_pgo_target = "mac"
inputs = [ "//chrome/build/mac.pgo.txt" ]
} else if (is_linux || is_chromeos_lacros) {
_pgo_target = "linux"
inputs = [ "//chrome/build/linux.pgo.txt" ]
}
if (pgo_data_path == "" && _pgo_target != "") {
pgo_data_path = rebase_path(exec_script("//tools/update_pgo_profiles.py",
[
"--target",
_pgo_target,
"get_profile_path",
],
"value"),
root_build_dir)
}
assert(pgo_data_path != "",
"Please set pgo_data_path to point at the profile data")
cflags = [
"-fprofile-instr-use=$pgo_data_path",
# It's possible to have some profile data legitimately missing,
# and at least some profile data always ends up being considered
# out of date, so make sure we don't error for those cases.
"-Wno-profile-instr-unprofiled",
"-Wno-profile-instr-out-of-date",
# Some hashing conflict results in a lot of warning like this when doing
# a PGO build:
# warning: foo.cc: Function control flow change detected (hash mismatch)
# [-Wbackend-plugin]
# See
https://crbug.com/978401
"-Wno-backend-plugin",
]
}
}
# Applies flags necessary when profile-guided optimization is used.
# Flags are only added if PGO is enabled, so that this config is safe to
# include by default.
config("default_pgo_flags") {
if (chrome_pgo_phase == 0) {
# Nothing. This config should be a no-op when chrome_pgo_phase == 0.
} else if (chrome_pgo_phase == 1) {
configs = [ ":pgo_instrumentation_flags" ]
} else if (chrome_pgo_phase == 2) {
configs = [ ":pgo_optimization_flags" ]
}
}
