mirrored from https://chromium.googlesource.com/v8/v8.git
/
BUILD.gn
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BUILD.gn
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# Copyright 2014 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("//build/config/android/config.gni")
import("//build/config/arm.gni")
import("//build/config/coverage/coverage.gni")
import("//build/config/dcheck_always_on.gni")
import("//build/config/host_byteorder.gni")
import("//build/config/mips.gni")
import("//build/config/riscv.gni")
import("//build/config/sanitizers/sanitizers.gni")
import("//build_overrides/build.gni")
import("gni/snapshot_toolchain.gni")
import("gni/v8.gni")
# Specifies if the target build is a simulator build. Comparing target cpu
# with v8 target cpu to not affect simulator builds for making cross-compile
# snapshots.
target_is_simulator = (target_cpu != v8_target_cpu && !v8_multi_arch_build) ||
(current_cpu != v8_current_cpu && v8_multi_arch_build)
# For faster Windows builds. See https://crbug.com/v8/8475.
emit_builtins_as_inline_asm = is_win && is_clang
declare_args() {
# Print to stdout on Android.
v8_android_log_stdout = false
# Dynamically set an additional dependency from v8/custom_deps.
v8_custom_deps = ""
# Turns on all V8 debug features. Enables running V8 in a pseudo debug mode
# within a release Chrome.
v8_enable_debugging_features = is_debug
# Sets -DV8_ENABLE_FUTURE.
v8_enable_future = false
# Sets -DENABLE_SYSTEM_INSTRUMENTATION. Enables OS-dependent event tracing
v8_enable_system_instrumentation = (is_win || is_mac) && !v8_use_perfetto
# Sets -DV8_ENABLE_ETW_STACK_WALKING. Enables ETW Stack Walking
v8_enable_etw_stack_walking = is_win
# Sets the GUID for the ETW provider
v8_etw_guid = ""
# Sets -DVERIFY_HEAP.
v8_enable_verify_heap = ""
# Sets -DVERIFY_PREDICTABLE
v8_enable_verify_predictable = false
# Enable compiler warnings when using V8_DEPRECATED apis.
v8_deprecation_warnings = true
# Enable compiler warnings when using V8_DEPRECATE_SOON apis.
v8_imminent_deprecation_warnings = true
# Embeds the given script into the snapshot.
v8_embed_script = ""
# Allows the embedder to add a custom suffix to the version string.
v8_embedder_string = ""
# Sets -dENABLE_DISASSEMBLER.
v8_enable_disassembler = ""
# Sets the number of internal fields on promise objects.
v8_promise_internal_field_count = 0
# Sets -dENABLE_GDB_JIT_INTERFACE.
v8_enable_gdbjit = ""
# Sets -dENABLE_VTUNE_JIT_INTERFACE.
v8_enable_vtunejit = false
# Sets -dENABLE_VTUNE_TRACEMARK.
v8_enable_vtunetracemark = false
# Sets -dENABLE_HUGEPAGE
v8_enable_hugepage = false
# Sets -dV8_ENABLE_PRIVATE_MAPPING_FORK_OPTIMIZATION.
#
# This flag speeds up the performance of fork/execve on Linux systems for
# embedders which use it (like Node.js). It works by marking the pages that
# V8 allocates as MADV_DONTFORK. Without MADV_DONTFORK, the Linux kernel
# spends a long time manipulating page mappings on fork and exec which the
# child process doesn't generally need to access.
#
# See v8:7381 for more details.
v8_enable_private_mapping_fork_optimization = false
# Sets -dENABLE_HANDLE_ZAPPING.
v8_enable_handle_zapping = is_asan || is_debug
# Enable slow dchecks.
v8_enable_slow_dchecks = false
# Enable fast mksnapshot runs.
v8_enable_fast_mksnapshot = false
# Optimize code for Torque executable, even during a debug build.
v8_enable_fast_torque = ""
# Enable the registration of unwinding info for Windows x64 and ARM64.
v8_win64_unwinding_info = true
# Enable code comments for builtins in the snapshot (impacts performance).
# This also enables v8_code_comments.
v8_enable_snapshot_code_comments = false
# Allow runtime-enabled code comments (with --code-comments). Enabled by
# default in debug builds.
# Sets -dV8_CODE_COMMENTS
v8_code_comments = ""
# Allow runtime-enabled debug code (with --debug-code). Enabled by default in
# debug builds.
# Sets -dV8_ENABLE_DEBUG_CODE
v8_enable_debug_code = ""
# Enable native counters from the snapshot (impacts performance, sets
# -dV8_SNAPSHOT_NATIVE_CODE_COUNTERS).
# This option will generate extra code in the snapshot to increment counters,
# as per the --native-code-counters flag.
v8_enable_snapshot_native_code_counters = ""
# Use pre-generated static root pointer values from static-roots.h.
v8_enable_static_roots = ""
# Mode used by gen-static-roots.py to have a heap layout which is identical
# to when v8_enable_static_roots is enabled.
v8_enable_static_roots_generation = false
# Enable code-generation-time checking of types in the CodeStubAssembler.
v8_enable_verify_csa = false
# Enable pointer compression (sets -dV8_COMPRESS_POINTERS).
v8_enable_pointer_compression = ""
v8_enable_pointer_compression_shared_cage = ""
v8_enable_31bit_smis_on_64bit_arch = false
# Sets -dOBJECT_PRINT.
v8_enable_object_print = ""
# Sets -dV8_TRACE_MAPS.
v8_enable_trace_maps = ""
# Sets -dV8_ENABLE_CHECKS.
v8_enable_v8_checks = ""
# Sets -dV8_TRACE_UNOPTIMIZED.
v8_enable_trace_unoptimized = ""
v8_enable_trace_ignition = false
v8_enable_trace_baseline_exec = false
# Sets -dV8_TRACE_FEEDBACK_UPDATES.
v8_enable_trace_feedback_updates = false
# Sets -dV8_ATOMIC_OBJECT_FIELD_WRITES and turns all field write operations
# into relaxed atomic operations.
v8_enable_atomic_object_field_writes = ""
# Controls the default value of v8_enable_concurrent_marking_state. See the
# default setting code below.
v8_enable_concurrent_marking = true
# Sets -dV8_IGNITION_DISPATCH_COUNTING.
# Enables counting frequencies of bytecode dispatches. After building in this
# configuration, subsequent runs of d8 can output frequencies for each pair
# of (current, next) bytecode instructions executed if you specify
# --trace-ignition-dispatches-output-file, or can generate a JS object with
# those frequencies if you run with --expose-ignition-statistics and call the
# extension function getIgnitionDispatchCounters().
v8_enable_ignition_dispatch_counting = false
# Runs mksnapshot with --turbo-profiling. After building in this
# configuration, any subsequent run of d8 will output information about usage
# of basic blocks in builtins.
v8_enable_builtins_profiling = false
# Runs mksnapshot with --turbo-profiling-verbose. After building in this
# configuration, any subsequent run of d8 will output information about usage
# of basic blocks in builtins, including the schedule and disassembly of all
# used builtins.
v8_enable_builtins_profiling_verbose = false
# This build flag is used to input a builtin pgo file containing raw
# execution counts (as opposed to branch hints), which are embedded into
# the `--trace-turbo` .json file from `mksnapshot`.
v8_log_builtins_block_count_input = ""
# This build flag is used to control whether reorder builtins acoording to
# the call graph with C3 algorithm based builtin PGO profiling.
v8_enable_builtins_reordering = true
# Provides the given V8 log file as an input to mksnapshot, where it can be
# used for profile-guided optimization of builtins.
#
# To do profile-guided optimizations of builtins:
# 1. Build with v8_enable_builtins_profiling = true
# 2. Run your chosen workload with the --turbo-profiling-output flag.
# For Chrome, the invocation might look like this:
# chrome --no-sandbox --disable-extensions
# --js-flags="--turbo-profiling-output=v8.builtins.pgo"
# "http://localhost/test-suite"
# 3. Run tools/builtins-pgo/get_hints.py to produce the branch hints,
# selecting min_count and threshold_ratio as you wish.
# 4. Optionally repeat steps 2-3 for additional workloads, and use
# tools/builtins-pgo/combine_hints.py to combine the hints produced in
# step 3 into a single file.
# 5. Build again with v8_builtins_profiling_log_file set to the file created
# in step 3 or 4.
v8_builtins_profiling_log_file = "default"
# Enables various testing features.
v8_enable_test_features = ""
# Enable short builtins call instruction sequences by un-embedding builtins.
# Sets -dV8_SHORT_BUILTIN_CALLS
v8_enable_short_builtin_calls = ""
# Enable support for external code range relative to the pointer compression
# cage.
# Sets -dV8_EXTERNAL_CODE_SPACE
v8_enable_external_code_space = ""
# 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.
v8_postmortem_support = false
# Use Siphash as added protection against hash flooding attacks.
v8_use_siphash = false
# Switches off inlining in V8.
v8_no_inline = false
# Override OS page size when generating snapshot
v8_os_page_size = "0"
# Similar to vfp but on MIPS.
v8_can_use_fpu_instructions = true
# Similar to the ARM hard float ABI but on MIPS.
v8_use_mips_abi_hardfloat = true
# Controls the threshold for on-heap/off-heap Typed Arrays.
v8_typed_array_max_size_in_heap = 64
v8_enable_gdbjit = ((v8_current_cpu == "x86" || v8_current_cpu == "x64") &&
(is_linux || is_chromeos || is_mac)) ||
(v8_current_cpu == "ppc64" && (is_linux || is_chromeos))
# Check that each header can be included in isolation (requires also
# setting the "check_v8_header_includes" gclient variable to run a
# specific hook).
v8_check_header_includes = false
# Enable sharing read-only space across isolates.
# Sets -DV8_SHARED_RO_HEAP.
v8_enable_shared_ro_heap = ""
# Enable lazy source positions by default.
v8_enable_lazy_source_positions = true
# Enable third party HEAP library
v8_enable_third_party_heap = false
# Libaries used by third party heap
v8_third_party_heap_libs = []
# Source code used by third party heap
v8_third_party_heap_files = []
# Disable write barriers when GCs are non-incremental and
# heap has single generation.
v8_disable_write_barriers = false
# Ensure that write barriers are always used.
# Useful for debugging purposes.
v8_enable_unconditional_write_barriers = false
# Redirect allocation in young generation so that there will be
# only one single generation.
v8_enable_single_generation = ""
# Use token threaded dispatch for the regular expression interpreter.
# Use switch-based dispatch if this is false
v8_enable_regexp_interpreter_threaded_dispatch = true
# Enforce equality of builtins hashes from compatible architectures.
v8_verify_builtins_compatibility = false
# Check mksnapshot determinism by running it multiple times.
v8_verify_deterministic_mksnapshot = false
# Enable additional targets necessary for verification of torque
# file generation
v8_verify_torque_generation_invariance = false
# Generate comments describing the Torque intermediate representation.
v8_annotate_torque_ir = false
# Enable snapshot compression (enabled by default for desktop) devices.
v8_enable_snapshot_compression =
target_os == "android" || target_os == "chromeos" ||
target_os == "fuchsia"
# Enable control-flow integrity features, such as pointer authentication for
# ARM64. Enable it by default for simulator builds and when native code
# supports it as well.
v8_control_flow_integrity =
v8_current_cpu == "arm64" &&
(target_is_simulator || arm_control_flow_integrity != "none")
# Enable heap reservation of size 4GB. Only possible for 64bit archs.
cppgc_enable_caged_heap =
v8_current_cpu == "x64" || v8_current_cpu == "arm64" ||
v8_current_cpu == "loong64" || v8_current_cpu == "riscv64"
# Enables additional heap verification phases and checks.
cppgc_enable_verify_heap = ""
# Enable allocations during prefinalizer invocations.
cppgc_allow_allocations_in_prefinalizers = false
# Enable V8 zone compression experimental feature.
# Sets -DV8_COMPRESS_ZONES.
v8_enable_zone_compression = ""
# Enable the V8 sandbox.
# Sets -DV8_ENABLE_SANDBOX.
v8_enable_sandbox = ""
# Enable the memory corruption API. Useful for testing the sandbox.
# The memory corruption API is only exposed to JavaScript if sandbox testing
# mode is enabled at runtime, for example via --sandbox-fuzzing.
# WARNING This will enable builtins that (by design) cause memory corruption.
# Sets -DV8_ENABLE_MEMORY_CORRUPTION_API
v8_enable_memory_corruption_api = false
# Experimental feature for collecting per-class zone memory stats.
# Requires use_rtti = true
v8_enable_precise_zone_stats = false
# Experimental feature that uses SwissNameDictionary instead of NameDictionary
# as the backing store for all dictionary mode objects.
v8_enable_swiss_name_dictionary = false
# If enabled then macro definitions that are used in externally visible
# header files are placed in a separate header file v8-gn.h.
v8_generate_external_defines_header = false
# Experimental feature for tracking constness of properties in non-global
# dictionaries. Enabling this also always keeps prototypes in dict mode,
# meaning that they are not switched to fast mode.
# Sets -DV8_DICT_PROPERTY_CONST_TRACKING
v8_dict_property_const_tracking = false
# Enable map packing & unpacking (sets -dV8_MAP_PACKING).
v8_enable_map_packing = false
# Allow for JS promise hooks (instead of just C++).
v8_enable_javascript_promise_hooks = false
# Allow embedder data to be saved on continuations. Used to support
# TaskAttribution and `scheduler.yield()`.
# The flag enables disabling the feature, to test this data's overhead.
v8_enable_continuation_preserved_embedder_data = true
# Enable allocation folding globally (sets -dV8_ALLOCATION_FOLDING).
# When it's disabled, the --turbo-allocation-folding runtime flag will be ignored.
v8_enable_allocation_folding = true
# Enable runtime verification of heap snapshots produced for devtools.
v8_enable_heap_snapshot_verify = ""
# Enable global allocation site tracking.
v8_allocation_site_tracking = true
# TODO(cbruni, v8:12302): Remove once API is migrated
# Enable legacy mode for ScriptOrModule's lifetime. By default it's a
# temporary object, if enabled it will be kept alive by the parent Script.
# This is only used by nodejs.
v8_scriptormodule_legacy_lifetime = false
# Enables pointer compression for 8GB heaps.
# Sets -DV8_COMPRESS_POINTERS_8GB.
v8_enable_pointer_compression_8gb = ""
# Compile V8 using zlib as dependency.
# Sets -DV8_USE_ZLIB
v8_use_zlib = true
# Make ValueDeserializer crash if the data to deserialize is invalid.
v8_value_deserializer_hard_fail = false
# Enable jitless mode, including compile-time optimizations. Note that even
# when this is set to 'false', one can run V8 in jitless mode at runtime by
# passing the `--jitless` flag; but then you miss out on compile-time
# optimizations.
v8_jitless = v8_enable_lite_mode
# Enable Sparkplug
# Sets -DV8_ENABLE_SPARKPLUG.
v8_enable_sparkplug = ""
# Enable Maglev's graph printer.
# Sets -DV8_ENABLE_MAGLEV_GRAPH_PRINTER.
v8_enable_maglev_graph_printer = !build_with_chromium
# Enable slow tracing, e.g., tracing on every instruction or Turbofan node.
# Sets -DV8_ENABLE_SLOW_TRACING.
v8_enable_slow_tracing = is_debug
# Enable jump table switch for built-in.
v8_enable_builtin_jump_table_switch = v8_current_cpu == "x64"
v8_shortcut_strings_in_minor_ms = false
# Whether custom embedder snapshots may extend (= allocate new objects in)
# ReadOnlySpace.
v8_enable_extensible_ro_snapshot = true
# Use sticky mark-bits for separating object generations.
v8_enable_sticky_mark_bits = false
# Always move prototype transitions to the start of the transition tree
# (see issue 332914927).
v8_move_prototype_transitions_first = false
}
# Derived defaults.
if (cppgc_enable_verify_heap == "") {
cppgc_enable_verify_heap = v8_enable_debugging_features || dcheck_always_on
}
if (v8_enable_verify_heap == "") {
v8_enable_verify_heap = v8_enable_debugging_features
}
if (v8_enable_object_print == "") {
v8_enable_object_print = v8_enable_debugging_features
}
if (v8_enable_disassembler == "") {
v8_enable_disassembler = v8_enable_debugging_features
}
if (v8_enable_trace_maps == "") {
v8_enable_trace_maps = v8_enable_debugging_features
}
if (v8_enable_test_features == "") {
v8_enable_test_features = v8_enable_debugging_features || dcheck_always_on
}
if (v8_enable_v8_checks == "") {
v8_enable_v8_checks = v8_enable_debugging_features
}
if (v8_enable_heap_snapshot_verify == "") {
v8_enable_heap_snapshot_verify =
v8_enable_debugging_features || dcheck_always_on
}
if (v8_enable_snapshot_code_comments) {
assert(v8_code_comments == true || v8_code_comments == "",
"v8_enable_snapshot_code_comments conflicts with v8_code_comments.")
v8_code_comments = true
} else if (v8_code_comments == "") {
v8_code_comments = v8_enable_debugging_features
}
if (v8_enable_debug_code == "") {
v8_enable_debug_code = v8_enable_debugging_features
}
if (v8_enable_snapshot_native_code_counters == "") {
v8_enable_snapshot_native_code_counters = v8_enable_debugging_features
}
if (v8_enable_pointer_compression == "") {
v8_enable_pointer_compression =
v8_current_cpu == "arm64" || v8_current_cpu == "x64"
}
# Toggle pointer compression for correctness fuzzing when building the
# clang_x64_pointer_compression toolchain. We'll correctness-compare the
# default build with the clang_x64_pointer_compression build.
if (v8_multi_arch_build &&
rebase_path(get_label_info(":d8", "root_out_dir"), root_build_dir) ==
"clang_x64_pointer_compression") {
v8_enable_pointer_compression = !v8_enable_pointer_compression
}
# Ensure the sandbox is on/off in the same way as pointer compression for
# correctness fuzzing builds.
if (v8_multi_arch_build) {
v8_enable_sandbox = v8_enable_pointer_compression
}
if (v8_enable_pointer_compression_shared_cage == "") {
v8_enable_pointer_compression_shared_cage = v8_enable_pointer_compression
}
if (v8_enable_pointer_compression_8gb == "") {
v8_enable_pointer_compression_8gb = false
}
if (v8_enable_fast_torque == "") {
v8_enable_fast_torque = v8_enable_fast_mksnapshot
}
if (v8_enable_zone_compression == "") {
v8_enable_zone_compression = false
}
if (v8_enable_short_builtin_calls == "") {
v8_enable_short_builtin_calls =
v8_current_cpu == "x64" || v8_current_cpu == "arm64"
}
if (v8_enable_external_code_space == "") {
v8_enable_external_code_space =
v8_enable_pointer_compression &&
v8_enable_pointer_compression_shared_cage &&
(v8_current_cpu == "x64" || v8_current_cpu == "arm64")
}
if (v8_enable_sparkplug == "") {
v8_enable_sparkplug = !v8_jitless
}
if (v8_enable_maglev == "") {
v8_enable_maglev = v8_enable_turbofan &&
(v8_current_cpu == "arm" || v8_current_cpu == "x64" ||
v8_current_cpu == "arm64")
}
assert(v8_enable_turbofan || !v8_enable_maglev,
"Maglev is not available when Turbofan is disabled.")
assert(!v8_jitless || (!v8_enable_sparkplug && !v8_enable_maglev &&
!v8_enable_turbofan && !v8_enable_webassembly),
"Sparkplug, Maglev, Turbofan and Wasm are not available in jitless mode")
if (v8_enable_single_generation == "") {
v8_enable_single_generation = v8_disable_write_barriers
}
if (v8_enable_atomic_object_field_writes == "") {
v8_enable_atomic_object_field_writes = v8_enable_concurrent_marking
}
if (v8_enable_third_party_heap) {
v8_disable_write_barriers = true
v8_enable_single_generation = true
v8_enable_shared_ro_heap = false
v8_enable_pointer_compression = false
v8_enable_pointer_compression_shared_cage = false
v8_enable_allocation_folding = false
}
if (v8_enable_single_generation) {
v8_allocation_site_tracking = false
}
assert(!v8_enable_concurrent_marking || v8_enable_atomic_object_field_writes,
"Concurrent marking requires atomic object field writes.")
if (v8_enable_trace_unoptimized == "") {
v8_enable_trace_unoptimized =
v8_enable_trace_ignition || v8_enable_trace_baseline_exec
}
assert(!v8_enable_trace_ignition || v8_enable_trace_unoptimized,
"Ignition tracing requires unoptimized tracing to be enabled.")
assert(!v8_enable_trace_baseline_exec || v8_enable_trace_unoptimized,
"Baseline tracing requires unoptimized tracing to be enabled.")
assert(
v8_enable_debugging_features == true || dcheck_always_on ||
!v8_enable_slow_dchecks,
"v8_enable_slow_dchecks requires v8_enable_debugging_features or dcheck_always_on.")
if (v8_enable_short_builtin_calls &&
(!v8_enable_pointer_compression && v8_current_cpu != "x64")) {
# Disable short calls when pointer compression is not enabled, except x64,
# where short builtin calls can still be enabled if the code range is
# guaranteed to be close enough to embedded builtins.
v8_enable_short_builtin_calls = false
}
if (v8_enable_shared_ro_heap == "") {
v8_enable_shared_ro_heap = !v8_enable_pointer_compression ||
v8_enable_pointer_compression_shared_cage
}
if (v8_enable_sandbox == "") {
# TODO(saelo, v8:11880) remove dependency on v8_enable_external_code_space
# once that is enabled everywhere by default.
# TODO(chromium:1325784) the sandbox is not currently supported in Chromium
# on Fuchsia.
v8_enable_sandbox = v8_enable_pointer_compression_shared_cage &&
v8_enable_external_code_space && target_os != "fuchsia"
}
if (v8_enable_static_roots == "") {
# Static roots are only valid for builds with pointer compression and a
# shared read-only heap.
# TODO(olivf, v8:13466) Some configurations could be supported if we
# introduce different static root files for different build configurations:
# Non-wasm and non-i18n builds have fewer read only roots. Configurations
# without external code space allocate read only roots at a further
# location relative to the cage base.
v8_enable_static_roots =
v8_enable_pointer_compression && v8_enable_shared_ro_heap &&
v8_enable_pointer_compression_shared_cage &&
v8_enable_external_code_space && v8_enable_webassembly &&
v8_enable_i18n_support
}
assert(!v8_enable_static_roots ||
(v8_enable_pointer_compression && v8_enable_shared_ro_heap &&
v8_enable_pointer_compression_shared_cage &&
v8_enable_external_code_space && v8_enable_webassembly &&
v8_enable_i18n_support),
"Trying to enable static roots in a configuration that is not supported")
assert(
!(v8_enable_static_roots && v8_enable_static_roots_generation),
"Static root values must be generated in a build that does not rely on static roots itself")
if (v8_builtins_profiling_log_file == "default") {
v8_builtins_profiling_log_file = ""
# The existing profile can be used only when
# * `v8_enable_builtins_optimization` - this switch enables builtins PGO,
# * `!v8_enable_builtins_profiling` - don't use the profiles when generating
# a new one,
# * `!is_debug && !dcheck_always_on` - these modes add more checks to
# the builtins control flow which makes the builtins code different,
# * `v8_enable_pointer_compression` - it changes the objects layouts,
# * `v8_enable_sandbox && v8_enable_external_code_space` because they affect
# the way how external pointer values are accessed,
# * `v8_enable_webassembly` because it changes the set of opcodes which
# affects graphs hashes.
if (v8_enable_builtins_optimization && !v8_enable_builtins_profiling &&
!is_debug && !dcheck_always_on && v8_enable_webassembly) {
# This is about function arguments evaluation order on the machine building
# mksnapshot, which makes node IDs not predictable for subgraphs like
# Op1(Op2(), Op3()) and as a result different graph hashes.
# Clang uses left-to-right order everywhere except Windows, otherwise the
# order is right-to-left.
# TODO(crbug.com/v8/13647): Remove once this issue is fixed in CSA.
if (!is_clang || host_os == "win") {
pgo_profile_suffix = "-rl"
} else {
pgo_profile_suffix = ""
}
if ((v8_current_cpu == "x64" || v8_current_cpu == "arm64") &&
v8_enable_pointer_compression && v8_enable_external_code_space &&
v8_enable_sandbox) {
# Note, currently x64 profile can be applied to arm64 but not the other
# way round.
v8_builtins_profiling_log_file =
"tools/builtins-pgo/profiles/x64" + pgo_profile_suffix + ".profile"
} else if (v8_current_cpu == "x86" || v8_current_cpu == "arm") {
# Note, x86 profile can be applied to arm but not the other way round.
v8_builtins_profiling_log_file =
"tools/builtins-pgo/profiles/x86" + pgo_profile_suffix + ".profile"
}
}
}
if (v8_enable_webassembly && !target_is_simulator && v8_current_cpu == "x64") {
v8_enable_wasm_simd256_revec = true
}
assert(!v8_disable_write_barriers || v8_enable_single_generation,
"Disabling write barriers works only with single generation")
assert(v8_current_cpu == "arm64" || !v8_control_flow_integrity,
"Control-flow integrity is only supported on arm64")
if (v8_enable_shared_ro_heap && v8_enable_pointer_compression &&
!v8_enable_pointer_compression_shared_cage) {
assert(
is_linux || is_chromeos || is_android,
"Sharing read-only heap with pointer compression is only supported on Linux or Android")
}
assert(!v8_enable_map_packing || !v8_enable_pointer_compression,
"Map packing does not support pointer compression")
assert(!v8_enable_map_packing || v8_current_cpu == "x64",
"Map packing is only supported on x64")
assert(!v8_enable_external_code_space || v8_enable_pointer_compression,
"External code space feature requires pointer compression")
assert(!v8_enable_pointer_compression_8gb || v8_enable_pointer_compression,
"Pointer compression for 8GB cages requires pointer compression")
assert(!v8_enable_sandbox || v8_enable_pointer_compression_shared_cage,
"The sandbox requires the shared pointer compression cage")
assert(!v8_enable_sandbox || v8_enable_external_code_space,
"The sandbox requires the external code space")
assert(!v8_enable_sandbox || !v8_enable_third_party_heap,
"The sandbox is incompatible with the third-party heap")
assert(!v8_enable_memory_corruption_api || v8_enable_sandbox,
"The Memory Corruption API requires the sandbox")
assert(
!v8_enable_pointer_compression_shared_cage || v8_enable_pointer_compression,
"Can't share a pointer compression cage if pointers aren't compressed")
assert(
!v8_enable_pointer_compression_shared_cage || v8_current_cpu == "x64" ||
v8_current_cpu == "arm64" || v8_current_cpu == "riscv64" ||
v8_current_cpu == "ppc64" || v8_current_cpu == "s390x" ||
v8_current_cpu == "loong64",
"Sharing a pointer compression cage is only supported on x64, arm64, ppc64, s390x, riscv64 and loong64")
assert(!v8_enable_unconditional_write_barriers || !v8_disable_write_barriers,
"Write barriers can't be both enabled and disabled")
assert(!cppgc_enable_caged_heap || v8_current_cpu == "x64" ||
v8_current_cpu == "arm64" || v8_current_cpu == "loong64" ||
v8_current_cpu == "riscv64",
"CppGC caged heap requires 64bit platforms")
assert(!cppgc_enable_young_generation || cppgc_enable_caged_heap,
"Young generation in CppGC requires caged heap")
assert(!cppgc_enable_pointer_compression || cppgc_enable_caged_heap,
"Pointer compression in CppGC requires caged heap")
if (v8_enable_single_generation == true) {
assert(
v8_enable_unconditional_write_barriers || v8_disable_write_barriers,
"Requires unconditional write barriers or none (which disables incremental marking)")
}
assert(!v8_enable_snapshot_compression || v8_use_zlib,
"Snapshot compression requires zlib")
if (v8_expose_public_symbols == "") {
v8_expose_public_symbols = v8_expose_symbols
}
v8_random_seed = "314159265"
v8_toolset_for_shell = "host"
###############################################################################
# Configurations
#
config("internal_config_base") {
# Only targets in this file and its subdirs can depend on this.
visibility = [ "./*" ]
configs = [ ":v8_tracing_config" ]
include_dirs = [
".",
"include",
"$target_gen_dir",
]
}
config("internal_config") {
defines = []
# Only targets in this file and its subdirs can depend on this.
visibility = [ "./*" ]
configs = [
"//build/config/compiler:wexit_time_destructors",
":internal_config_base",
":v8_header_features",
":cppgc_header_features",
]
if (is_component_build) {
defines += [ "BUILDING_V8_SHARED_PRIVATE" ]
} else if (v8_expose_public_symbols) {
defines += [ "BUILDING_V8_SHARED" ]
}
if (v8_current_cpu == "riscv64" || v8_current_cpu == "riscv32") {
if (!is_clang) {
libs = [ "atomic" ]
}
}
}
# Should be applied to all targets that write trace events.
config("v8_tracing_config") {
if (v8_use_perfetto) {
include_dirs = [
"//third_party/perfetto/include",
"$root_gen_dir/third_party/perfetto",
"$root_gen_dir/third_party/perfetto/build_config",
]
}
}
# This config should be applied to code using the libplatform.
config("libplatform_config") {
include_dirs = [ "include" ]
if (is_component_build) {
defines = [ "USING_V8_PLATFORM_SHARED" ]
}
}
# This config should be applied to code using the libbase.
config("libbase_config") {
if (is_component_build) {
defines = [ "USING_V8_BASE_SHARED" ]
}
libs = []
if (is_android && current_toolchain != host_toolchain) {
libs += [ "log" ]
}
}
# Standalone cppgc cannot be built within chrome or with perfetto.
assert(!cppgc_is_standalone || !build_with_chromium)
assert(!cppgc_is_standalone || !v8_use_perfetto)
# This config should be applied to code using the cppgc_base.
config("cppgc_base_config") {
defines = []
if (cppgc_is_standalone) {
defines += [ "CPPGC_IS_STANDALONE" ]
}
}
# This config is only applied to v8_headers and is the basis for external_config
# but without setting the USING_V8_SHARED define, which means v8_headers can be
# used inside v8 itself.
config("headers_config") {
defines = []
configs = [
":v8_header_features",
":cppgc_header_features",
]
include_dirs = [ "include" ]
}
# This config should only be applied to code using V8 and not any V8 code
# itself.
config("external_config") {
configs = [ ":headers_config" ]
defines = []
if (is_component_build) {
defines += [
"USING_V8_SHARED",
"USING_V8_SHARED_PRIVATE",
]
}
if (current_cpu == "riscv64" || current_cpu == "riscv32") {
if (!is_clang) {
libs = [ "atomic" ]
}
}
}
# This config should only be applied to code that needs to be explicitly
# aware of whether we are using startup data or not.
config("external_startup_data") {
if (v8_use_external_startup_data) {
defines = [ "V8_USE_EXTERNAL_STARTUP_DATA" ]
}
}
# List of defines that can appear in externally visible header files and that
# are controlled by args.gn.
# Make sure the |v8_generate_features_json| action is also updated when adding
# or removing defines below.
external_v8_defines = [
"V8_ENABLE_CHECKS",
"V8_COMPRESS_POINTERS",
"V8_COMPRESS_POINTERS_IN_SHARED_CAGE",
"V8_31BIT_SMIS_ON_64BIT_ARCH",
"V8_COMPRESS_ZONES",
"V8_ENABLE_SANDBOX",
"V8_DEPRECATION_WARNINGS",
"V8_IMMINENT_DEPRECATION_WARNINGS",
"V8_USE_PERFETTO",
"V8_MAP_PACKING",
"V8_IS_TSAN",
"V8_ENABLE_CONSERVATIVE_STACK_SCANNING",
"V8_ENABLE_DIRECT_LOCAL",
"V8_MINORMS_STRING_SHORTCUTTING",
"V8_HAVE_TARGET_OS",
"V8_TARGET_OS_ANDROID",
"V8_TARGET_OS_FUCHSIA",
"V8_TARGET_OS_IOS",
"V8_TARGET_OS_LINUX",
"V8_TARGET_OS_MACOS",
"V8_TARGET_OS_WIN",
"V8_TARGET_OS_CHROMEOS",
]
enabled_external_v8_defines = []
if (v8_enable_v8_checks) {
enabled_external_v8_defines += [ "V8_ENABLE_CHECKS" ]
}
if (v8_enable_pointer_compression) {
enabled_external_v8_defines += [ "V8_COMPRESS_POINTERS" ]
if (v8_enable_pointer_compression_shared_cage) {
enabled_external_v8_defines += [ "V8_COMPRESS_POINTERS_IN_SHARED_CAGE" ]
}
}
if (v8_enable_pointer_compression || v8_enable_31bit_smis_on_64bit_arch) {
enabled_external_v8_defines += [ "V8_31BIT_SMIS_ON_64BIT_ARCH" ]
}
if (v8_enable_zone_compression) {
enabled_external_v8_defines += [ "V8_COMPRESS_ZONES" ]
}
if (v8_enable_sandbox) {
enabled_external_v8_defines += [ "V8_ENABLE_SANDBOX" ]
}
if (v8_deprecation_warnings) {
enabled_external_v8_defines += [ "V8_DEPRECATION_WARNINGS" ]
}
if (v8_imminent_deprecation_warnings) {
enabled_external_v8_defines += [ "V8_IMMINENT_DEPRECATION_WARNINGS" ]
}
if (v8_use_perfetto) {
enabled_external_v8_defines += [ "V8_USE_PERFETTO" ]
}
if (v8_enable_map_packing) {
enabled_external_v8_defines += [ "V8_MAP_PACKING" ]
}
if (is_tsan) {
enabled_external_v8_defines += [ "V8_IS_TSAN" ]
}
if (v8_enable_conservative_stack_scanning) {
enabled_external_v8_defines += [ "V8_ENABLE_CONSERVATIVE_STACK_SCANNING" ]
}
if (v8_enable_direct_local) {
enabled_external_v8_defines += [ "V8_ENABLE_DIRECT_LOCAL" ]
}
if (v8_shortcut_strings_in_minor_ms) {
enabled_external_v8_defines += [ "V8_MINORMS_STRING_SHORTCUTTING" ]
}
# V8_TARGET_OS_ defines. The target OS may differ from host OS e.g. in
# mksnapshot. We additionally set V8_HAVE_TARGET_OS to determine that a
# target OS has in fact been set; otherwise we internally assume that target
# OS == host OS (see v8config.h).
if (target_os == "android") {
enabled_external_v8_defines += [ "V8_HAVE_TARGET_OS" ]
enabled_external_v8_defines += [ "V8_TARGET_OS_ANDROID" ]
} else if (target_os == "fuchsia") {
enabled_external_v8_defines += [ "V8_HAVE_TARGET_OS" ]
enabled_external_v8_defines += [ "V8_TARGET_OS_FUCHSIA" ]
} else if (target_os == "ios") {
enabled_external_v8_defines += [ "V8_HAVE_TARGET_OS" ]
enabled_external_v8_defines += [ "V8_TARGET_OS_IOS" ]
} else if (target_os == "linux") {
enabled_external_v8_defines += [ "V8_HAVE_TARGET_OS" ]
enabled_external_v8_defines += [ "V8_TARGET_OS_LINUX" ]
} else if (target_os == "mac") {
enabled_external_v8_defines += [ "V8_HAVE_TARGET_OS" ]
enabled_external_v8_defines += [ "V8_TARGET_OS_MACOS" ]
} else if (target_os == "win") {
enabled_external_v8_defines += [ "V8_HAVE_TARGET_OS" ]
enabled_external_v8_defines += [ "V8_TARGET_OS_WIN" ]
} else if (target_os == "chromeos") {
enabled_external_v8_defines += [ "V8_HAVE_TARGET_OS" ]
enabled_external_v8_defines += [ "V8_TARGET_OS_CHROMEOS" ]
}
disabled_external_v8_defines = external_v8_defines - enabled_external_v8_defines
# Put defines that are used in public headers here; public headers are
# defined in "v8_headers" and are included by embedders of V8.
config("v8_header_features") {
visibility = [ ":*" ]
if (v8_generate_external_defines_header) {
defines = [ "V8_GN_HEADER" ]
} else {
defines = enabled_external_v8_defines
}
}
# List of defines that can appear in externally visible cppgc header files and
# that are controlled by args.gn.
external_cppgc_defines = [
"CPPGC_SUPPORTS_OBJECT_NAMES",
"CPPGC_CAGED_HEAP",
"CPPGC_SLIM_WRITE_BARRIER",
"CPPGC_YOUNG_GENERATION",
"CPPGC_POINTER_COMPRESSION",
"CPPGC_ENABLE_LARGER_CAGE",
]
enabled_external_cppgc_defines = []
if (cppgc_enable_object_names) {
enabled_external_cppgc_defines += [ "CPPGC_SUPPORTS_OBJECT_NAMES" ]
}
if (cppgc_enable_caged_heap) {
enabled_external_cppgc_defines += [ "CPPGC_CAGED_HEAP" ]
# Always enable young generation compile time flag if caged heap is enabled.
cppgc_enable_young_generation = true
# Pointer compression regresses binary size on Fuchsia by about 300K.
# However, the change improves Oilpan memory by 15-20% (2-4% of PMF),
# which is beneficial for memory-impoverished platforms.
cppgc_enable_pointer_compression = true