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flag-definitions.h
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flag-definitions.h
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// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// This file defines all of the flags. It is separated into different section,
// for Debug, Release, Logging and Profiling, etc. To add a new flag, find the
// correct section, and use one of the DEFINE_ macros, without a trailing ';'.
//
// This include does not have a guard, because it is a template-style include,
// which can be included multiple times in different modes. It expects to have
// a mode defined before it's included. The modes are FLAG_MODE_... below:
//
// PRESUBMIT_INTENTIONALLY_MISSING_INCLUDE_GUARD
#define DEFINE_IMPLICATION(whenflag, thenflag) \
DEFINE_VALUE_IMPLICATION(whenflag, thenflag, true)
// A weak implication will be overwritten by a normal implication or by an
// explicit flag.
#define DEFINE_WEAK_IMPLICATION(whenflag, thenflag) \
DEFINE_WEAK_VALUE_IMPLICATION(whenflag, thenflag, true)
#define DEFINE_WEAK_NEG_IMPLICATION(whenflag, thenflag) \
DEFINE_WEAK_VALUE_IMPLICATION(whenflag, thenflag, false)
#define DEFINE_NEG_IMPLICATION(whenflag, thenflag) \
DEFINE_VALUE_IMPLICATION(whenflag, thenflag, false)
#define DEFINE_NEG_NEG_IMPLICATION(whenflag, thenflag) \
DEFINE_NEG_VALUE_IMPLICATION(whenflag, thenflag, false)
// With FLAG_MODE_DECLARE we declare the fields in the {FlagValues} struct.
// Read-only flags are static constants instead of fields.
#if defined(FLAG_MODE_DECLARE)
#define FLAG_FULL(ftype, ctype, nam, def, cmt) FlagValue<ctype> nam{def};
#define FLAG_READONLY(ftype, ctype, nam, def, cmt) \
static constexpr FlagValue<ctype> nam{def};
// We need to define all of our default values so that the Flag structure can
// access them by pointer. These are just used internally inside of one .cc,
// for MODE_META, so there is no impact on the flags interface.
#elif defined(FLAG_MODE_DEFINE_DEFAULTS)
#define FLAG_FULL(ftype, ctype, nam, def, cmt) \
static constexpr ctype FLAGDEFAULT_##nam{def};
#define FLAG_READONLY(ftype, ctype, nam, def, cmt) \
static constexpr ctype FLAGDEFAULT_##nam{def};
// We want to write entries into our meta data table, for internal parsing and
// printing / etc in the flag parser code.
#elif defined(FLAG_MODE_META)
#define FLAG_FULL(ftype, ctype, nam, def, cmt) \
{Flag::TYPE_##ftype, #nam, &v8_flags.nam, &FLAGDEFAULT_##nam, cmt, false},
// Readonly flags don't pass the value pointer since the struct expects a
// mutable value. That's okay since the value always equals the default.
#define FLAG_READONLY(ftype, ctype, nam, def, cmt) \
{Flag::TYPE_##ftype, #nam, nullptr, &FLAGDEFAULT_##nam, cmt, false},
#define FLAG_ALIAS(ftype, ctype, alias, nam) \
{Flag::TYPE_##ftype, #alias, &v8_flags.nam, &FLAGDEFAULT_##nam, \
"alias for --" #nam, false}, // NOLINT(whitespace/indent)
// We produce the code to set flags when it is implied by another flag.
#elif defined(FLAG_MODE_DEFINE_IMPLICATIONS)
#define DEFINE_VALUE_IMPLICATION(whenflag, thenflag, value) \
changed |= TriggerImplication(v8_flags.whenflag, #whenflag, \
&v8_flags.thenflag, #thenflag, value, false);
// A weak implication will be overwritten by a normal implication or by an
// explicit flag.
#define DEFINE_WEAK_VALUE_IMPLICATION(whenflag, thenflag, value) \
changed |= TriggerImplication(v8_flags.whenflag, #whenflag, \
&v8_flags.thenflag, #thenflag, value, true);
#define DEFINE_GENERIC_IMPLICATION(whenflag, statement) \
if (v8_flags.whenflag) statement;
#define DEFINE_NEG_VALUE_IMPLICATION(whenflag, thenflag, value) \
changed |= TriggerImplication(!v8_flags.whenflag, "!" #whenflag, \
&v8_flags.thenflag, #thenflag, value, false);
#define DEFINE_NEG_VALUE_VALUE_IMPLICATION(whenflag, whenvalue, thenflag, \
thenvalue) \
changed |= \
TriggerImplication(v8_flags.whenflag != whenvalue, #whenflag, \
&v8_flags.thenflag, #thenflag, thenvalue, false);
#define DEFINE_MIN_VALUE_IMPLICATION(flag, min_value) \
changed |= TriggerImplication(v8_flags.flag < min_value, #flag, \
&v8_flags.flag, #flag, min_value, false);
#define DEFINE_DISABLE_FLAG_IMPLICATION(whenflag, thenflag) \
if (v8_flags.whenflag && v8_flags.thenflag) { \
PrintF(stderr, "Warning: disabling flag --" #thenflag \
" due to conflicting flags\n"); \
} \
DEFINE_VALUE_IMPLICATION(whenflag, thenflag, false)
// We apply a generic macro to the flags.
#elif defined(FLAG_MODE_APPLY)
#define FLAG_FULL FLAG_MODE_APPLY
#else
#error No mode supplied when including flags.defs
#endif
// Dummy defines for modes where it is not relevant.
#ifndef FLAG_FULL
#define FLAG_FULL(ftype, ctype, nam, def, cmt)
#endif
#ifndef FLAG_READONLY
#define FLAG_READONLY(ftype, ctype, nam, def, cmt)
#endif
#ifndef FLAG_ALIAS
#define FLAG_ALIAS(ftype, ctype, alias, nam)
#endif
#ifndef DEFINE_VALUE_IMPLICATION
#define DEFINE_VALUE_IMPLICATION(whenflag, thenflag, value)
#endif
#ifndef DEFINE_WEAK_VALUE_IMPLICATION
#define DEFINE_WEAK_VALUE_IMPLICATION(whenflag, thenflag, value)
#endif
#ifndef DEFINE_GENERIC_IMPLICATION
#define DEFINE_GENERIC_IMPLICATION(whenflag, statement)
#endif
#ifndef DEFINE_NEG_VALUE_IMPLICATION
#define DEFINE_NEG_VALUE_IMPLICATION(whenflag, thenflag, value)
#endif
#ifndef DEFINE_NEG_VALUE_VALUE_IMPLICATION
#define DEFINE_NEG_VALUE_VALUE_IMPLICATION(whenflag, whenvalue, thenflag, \
thenvalue)
#endif
#ifndef DEFINE_MIN_VALUE_IMPLICATION
#define DEFINE_MIN_VALUE_IMPLICATION(flag, min_value)
#endif
#ifndef DEFINE_DISABLE_FLAG_IMPLICATION
#define DEFINE_DISABLE_FLAG_IMPLICATION(whenflag, thenflag)
#endif
#ifndef DEBUG_BOOL
#error DEBUG_BOOL must be defined at this point.
#endif // DEBUG_BOOL
#if V8_ENABLE_SPARKPLUG
#define ENABLE_SPARKPLUG_BY_DEFAULT true
#else
#define ENABLE_SPARKPLUG_BY_DEFAULT false
#endif
// Supported ARM configurations are:
// "armv6": ARMv6 + VFPv2
// "armv7": ARMv7 + VFPv3-D32 + NEON
// "armv7+sudiv": ARMv7 + VFPv4-D32 + NEON + SUDIV
// "armv8": ARMv8 (including all of the above)
#if !defined(ARM_TEST_NO_FEATURE_PROBE) || \
(defined(CAN_USE_ARMV8_INSTRUCTIONS) && \
defined(CAN_USE_ARMV7_INSTRUCTIONS) && defined(CAN_USE_SUDIV) && \
defined(CAN_USE_NEON) && defined(CAN_USE_VFP3_INSTRUCTIONS))
#define ARM_ARCH_DEFAULT "armv8"
#elif defined(CAN_USE_ARMV7_INSTRUCTIONS) && defined(CAN_USE_SUDIV) && \
defined(CAN_USE_NEON) && defined(CAN_USE_VFP3_INSTRUCTIONS)
#define ARM_ARCH_DEFAULT "armv7+sudiv"
#elif defined(CAN_USE_ARMV7_INSTRUCTIONS) && defined(CAN_USE_NEON) && \
defined(CAN_USE_VFP3_INSTRUCTIONS)
#define ARM_ARCH_DEFAULT "armv7"
#else
#define ARM_ARCH_DEFAULT "armv6"
#endif
#ifdef V8_OS_WIN
#define ENABLE_LOG_COLOUR false
#else
#define ENABLE_LOG_COLOUR true
#endif
#define DEFINE_BOOL(nam, def, cmt) FLAG(BOOL, bool, nam, def, cmt)
#define DEFINE_BOOL_READONLY(nam, def, cmt) \
FLAG_READONLY(BOOL, bool, nam, def, cmt)
#define DEFINE_MAYBE_BOOL(nam, cmt) \
FLAG(MAYBE_BOOL, std::optional<bool>, nam, std::nullopt, cmt)
#define DEFINE_INT(nam, def, cmt) FLAG(INT, int, nam, def, cmt)
#define DEFINE_UINT(nam, def, cmt) FLAG(UINT, unsigned int, nam, def, cmt)
#define DEFINE_UINT_READONLY(nam, def, cmt) \
FLAG_READONLY(UINT, unsigned int, nam, def, cmt)
#define DEFINE_UINT64(nam, def, cmt) FLAG(UINT64, uint64_t, nam, def, cmt)
#define DEFINE_FLOAT(nam, def, cmt) FLAG(FLOAT, double, nam, def, cmt)
#define DEFINE_SIZE_T(nam, def, cmt) FLAG(SIZE_T, size_t, nam, def, cmt)
#define DEFINE_STRING(nam, def, cmt) FLAG(STRING, const char*, nam, def, cmt)
#define DEFINE_ALIAS_BOOL(alias, nam) FLAG_ALIAS(BOOL, bool, alias, nam)
#define DEFINE_ALIAS_INT(alias, nam) FLAG_ALIAS(INT, int, alias, nam)
#define DEFINE_ALIAS_FLOAT(alias, nam) FLAG_ALIAS(FLOAT, double, alias, nam)
#define DEFINE_ALIAS_SIZE_T(alias, nam) FLAG_ALIAS(SIZE_T, size_t, alias, nam)
#define DEFINE_ALIAS_STRING(alias, nam) \
FLAG_ALIAS(STRING, const char*, alias, nam)
#ifdef DEBUG
#define DEFINE_DEBUG_BOOL DEFINE_BOOL
#else
#define DEFINE_DEBUG_BOOL DEFINE_BOOL_READONLY
#endif
//
// Flags in all modes.
//
#define FLAG FLAG_FULL
// Experimental features.
// Features that are still considered experimental and which are not ready for
// fuzz testing should be defined using this macro. The feature will then imply
// --experimental, which will indicate to the user that they are running an
// experimental configuration of V8. Experimental features are always disabled
// by default. When these features mature, the flag should first turn into a
// regular feature flag (still disabled by default) and then ideally be staged
// behind (for example) --future before being enabled by default.
DEFINE_BOOL(experimental, false,
"Indicates that V8 is running with experimental features enabled. "
"This flag is typically not set explicitly but instead enabled as "
"an implication of other flags which enable experimental features.")
#define DEFINE_EXPERIMENTAL_FEATURE(nam, cmt) \
FLAG(BOOL, bool, nam, false, cmt " (experimental)") \
DEFINE_IMPLICATION(nam, experimental)
// ATTENTION: This is set to true by default in d8. But for API compatibility,
// it generally defaults to false.
DEFINE_BOOL(abort_on_contradictory_flags, false,
"Disallow flags or implications overriding each other.")
// This implication is also hard-coded into the flags processing to make sure it
// becomes active before we even process subsequent flags.
DEFINE_NEG_IMPLICATION(fuzzing, abort_on_contradictory_flags)
// As abort_on_contradictory_flags, but it will simply exit with return code 0.
DEFINE_BOOL(exit_on_contradictory_flags, false,
"Exit with return code 0 on contradictory flags.")
// We rely on abort_on_contradictory_flags to turn on the analysis.
DEFINE_WEAK_IMPLICATION(exit_on_contradictory_flags,
abort_on_contradictory_flags)
// This is not really a flag, it affects the interpretation of the next flag but
// doesn't become permanently true when specified. This only works for flags
// defined in this file, but not for d8 flags defined in src/d8/d8.cc.
DEFINE_BOOL(allow_overwriting_for_next_flag, false,
"temporary disable flag contradiction to allow overwriting just "
"the next flag")
// Flags for language modes and experimental language features.
DEFINE_BOOL(use_strict, false, "enforce strict mode")
DEFINE_BOOL(trace_temporal, false, "trace temporal code")
DEFINE_BOOL(harmony, false, "enable all completed harmony features")
DEFINE_BOOL(harmony_shipping, true, "enable all shipped harmony features")
DEFINE_BOOL(js_staging, false, "enable all completed JavaScript features")
DEFINE_BOOL(js_shipping, true, "enable all shipped JavaScript features")
// Update bootstrapper.cc whenever adding a new feature flag.
// Features that are still work in progress (behind individual flags).
//
// The "harmony" naming is now outdated and will no longer be used for new JS
// features. Use the JAVASCRIPT macros instead.
//
// TODO(v8:14214): Remove --harmony flags once transition is complete.
#define HARMONY_INPROGRESS_BASE(V) \
V(harmony_weak_refs_with_cleanup_some, \
"harmony weak references with FinalizationRegistry.prototype.cleanupSome") \
V(harmony_temporal, "Temporal") \
V(harmony_shadow_realm, "harmony ShadowRealm") \
V(harmony_struct, "harmony structs, shared structs, and shared arrays") \
V(harmony_import_assertions, "harmony import assertions (deprecated)")
#define JAVASCRIPT_INPROGRESS_FEATURES_BASE(V) \
V(js_explicit_resource_management, "explicit resource management") \
V(js_float16array, \
"Float16Array, Math.f16round, DataView.getFloat16, DataView.setFloat16") \
V(js_decorators, "decorators") \
V(js_source_phase_imports, "source phase imports")
#ifdef V8_INTL_SUPPORT
#define HARMONY_INPROGRESS(V) \
HARMONY_INPROGRESS_BASE(V) \
V(harmony_intl_best_fit_matcher, "Intl BestFitMatcher") \
/* Following two flags should ship the same time but may stage */ \
/* differently . */ \
V(harmony_remove_intl_locale_info_getters, \
"Remove Obsoleted Intl Locale Info getters")
#define JAVASCRIPT_INPROGRESS_FEATURES(V) JAVASCRIPT_INPROGRESS_FEATURES_BASE(V)
#else
#define HARMONY_INPROGRESS(V) HARMONY_INPROGRESS_BASE(V)
#define JAVASCRIPT_INPROGRESS_FEATURES(V) JAVASCRIPT_INPROGRESS_FEATURES_BASE(V)
#endif
// Features that are complete (but still behind the --harmony flag).
#define HARMONY_STAGED_BASE(V)
#define JAVASCRIPT_STAGED_FEATURES_BASE(V) V(js_atomics_pause, "Atomics.pause")
#ifdef V8_INTL_SUPPORT
#define HARMONY_STAGED(V) \
HARMONY_STAGED_BASE(V) \
V(harmony_intl_locale_info_func, "Intl Locale Info API as functions")
#define JAVASCRIPT_STAGED_FEATURES(V) JAVASCRIPT_STAGED_FEATURES_BASE(V)
#else
#define HARMONY_STAGED(V) HARMONY_STAGED_BASE(V)
#define JAVASCRIPT_STAGED_FEATURES(V) JAVASCRIPT_STAGED_FEATURES_BASE(V)
#endif
// Features that are shipping (turned on by default, but internal flag remains).
#define HARMONY_SHIPPING_BASE(V) \
V(harmony_iterator_helpers, "JavaScript iterator helpers") \
V(harmony_set_methods, "harmony Set Methods") \
V(harmony_import_attributes, "harmony import attributes")
#define JAVASCRIPT_SHIPPING_FEATURES_BASE(V) \
V(js_regexp_duplicate_named_groups, "RegExp duplicate named groups") \
V(js_regexp_modifiers, "RegExp modifiers") \
V(js_promise_try, "Promise.try")
#ifdef V8_INTL_SUPPORT
#define HARMONY_SHIPPING(V) \
HARMONY_SHIPPING_BASE(V) \
V(harmony_intl_duration_format, "Intl DurationFormat API")
#define JAVASCRIPT_SHIPPING_FEATURES(V) JAVASCRIPT_SHIPPING_FEATURES_BASE(V)
#else
#define HARMONY_SHIPPING(V) HARMONY_SHIPPING_BASE(V)
#define JAVASCRIPT_SHIPPING_FEATURES(V) JAVASCRIPT_SHIPPING_FEATURES_BASE(V)
#endif
// Once a shipping feature has proved stable in the wild, it will be dropped
// from HARMONY_SHIPPING, all occurrences of the FLAG_ variable are removed,
// and associated tests are moved from the harmony directory to the appropriate
// esN directory.
//
// In-progress features are not code complete and are considered experimental,
// i.e. not ready for fuzz testing.
#define FLAG_INPROGRESS_FEATURES(id, description) \
DEFINE_BOOL(id, false, \
"enable " #description " (in progress / experimental)") \
DEFINE_IMPLICATION(id, experimental)
HARMONY_INPROGRESS(FLAG_INPROGRESS_FEATURES)
JAVASCRIPT_INPROGRESS_FEATURES(FLAG_INPROGRESS_FEATURES)
#undef FLAG_INPROGRESS_FEATURES
#define FLAG_STAGED_FEATURES(id, description) \
DEFINE_BOOL(id, false, "enable " #description) \
DEFINE_IMPLICATION(harmony, id) \
DEFINE_IMPLICATION(js_staging, id)
HARMONY_STAGED(FLAG_STAGED_FEATURES)
JAVASCRIPT_STAGED_FEATURES(FLAG_STAGED_FEATURES)
DEFINE_IMPLICATION(harmony, js_staging)
#undef FLAG_STAGED_FEATURES
#define FLAG_SHIPPING_FEATURES(id, description) \
DEFINE_BOOL(id, true, "enable " #description) \
DEFINE_NEG_NEG_IMPLICATION(harmony_shipping, id) \
DEFINE_NEG_NEG_IMPLICATION(js_shipping, id)
HARMONY_SHIPPING(FLAG_SHIPPING_FEATURES)
JAVASCRIPT_SHIPPING_FEATURES(FLAG_SHIPPING_FEATURES)
DEFINE_NEG_NEG_IMPLICATION(harmony_shipping, js_shipping)
#undef FLAG_SHIPPING_FEATURES
DEFINE_BOOL(builtin_subclassing, true,
"subclassing support in built-in methods")
// If the following flag is set to `true`, the SharedArrayBuffer constructor is
// enabled per context depending on the callback set via
// `SetSharedArrayBufferConstructorEnabledCallback`. If no callback is set, the
// SharedArrayBuffer constructor is disabled.
DEFINE_BOOL(enable_sharedarraybuffer_per_context, false,
"enable the SharedArrayBuffer constructor per context")
#ifdef V8_INTL_SUPPORT
DEFINE_BOOL(icu_timezone_data, true, "get information about timezones from ICU")
#endif
#ifdef V8_ENABLE_DOUBLE_CONST_STORE_CHECK
#define V8_ENABLE_DOUBLE_CONST_STORE_CHECK_BOOL true
#else
#define V8_ENABLE_DOUBLE_CONST_STORE_CHECK_BOOL false
#endif
#ifdef V8_ENABLE_LAZY_SOURCE_POSITIONS
#define V8_LAZY_SOURCE_POSITIONS_BOOL true
#else
#define V8_LAZY_SOURCE_POSITIONS_BOOL false
#endif
#ifdef V8_SHARED_RO_HEAP
#define V8_SHARED_RO_HEAP_BOOL true
#else
#define V8_SHARED_RO_HEAP_BOOL false
#endif
DEFINE_BOOL(stress_snapshot, false,
"disables sharing of the read-only heap for testing")
// Incremental marking is incompatible with the stress_snapshot mode;
// specifically, serialization may clear bytecode arrays from shared function
// infos which the MarkCompactCollector (running concurrently) may still need.
// See also https://crbug.com/v8/10882.
//
// Note: This is not an issue in production because we don't clear SFI's
// there (that only happens in mksnapshot and in --stress-snapshot mode).
DEFINE_NEG_IMPLICATION(stress_snapshot, incremental_marking)
#ifdef V8_LITE_MODE
#define V8_LITE_MODE_BOOL true
#else
#define V8_LITE_MODE_BOOL false
#endif
DEFINE_BOOL(lite_mode, V8_LITE_MODE_BOOL,
"enables trade-off of performance for memory savings")
// Lite mode implies other flags to trade-off performance for memory.
DEFINE_IMPLICATION(lite_mode, jitless)
DEFINE_IMPLICATION(lite_mode, optimize_for_size)
#ifdef V8_ENABLE_THIRD_PARTY_HEAP
#define V8_ENABLE_THIRD_PARTY_HEAP_BOOL true
#else
#define V8_ENABLE_THIRD_PARTY_HEAP_BOOL false
#endif
DEFINE_NEG_IMPLICATION(enable_third_party_heap, inline_new)
DEFINE_NEG_IMPLICATION(enable_third_party_heap, allocation_site_pretenuring)
DEFINE_NEG_IMPLICATION(enable_third_party_heap, turbo_allocation_folding)
DEFINE_NEG_IMPLICATION(enable_third_party_heap, concurrent_recompilation)
DEFINE_NEG_IMPLICATION(enable_third_party_heap, script_streaming)
DEFINE_NEG_IMPLICATION(enable_third_party_heap,
parallel_compile_tasks_for_eager_toplevel)
DEFINE_NEG_IMPLICATION(enable_third_party_heap, use_marking_progress_bar)
DEFINE_NEG_IMPLICATION(enable_third_party_heap, move_object_start)
DEFINE_NEG_IMPLICATION(enable_third_party_heap, concurrent_marking)
DEFINE_BOOL_READONLY(enable_third_party_heap, V8_ENABLE_THIRD_PARTY_HEAP_BOOL,
"Use third-party heap")
#ifdef V8_ALLOCATION_FOLDING
#define V8_ALLOCATION_FOLDING_BOOL true
#else
#define V8_ALLOCATION_FOLDING_BOOL false
#endif
DEFINE_BOOL_READONLY(enable_allocation_folding, V8_ALLOCATION_FOLDING_BOOL,
"Use allocation folding globally")
DEFINE_NEG_NEG_IMPLICATION(enable_allocation_folding, turbo_allocation_folding)
#ifdef V8_DISABLE_WRITE_BARRIERS
#define V8_DISABLE_WRITE_BARRIERS_BOOL true
#else
#define V8_DISABLE_WRITE_BARRIERS_BOOL false
#endif
DEFINE_BOOL_READONLY(disable_write_barriers, V8_DISABLE_WRITE_BARRIERS_BOOL,
"disable write barriers when GC is non-incremental "
"and heap contains single generation.")
// Disable incremental marking barriers
DEFINE_NEG_IMPLICATION(disable_write_barriers, incremental_marking)
DEFINE_NEG_IMPLICATION(disable_write_barriers, concurrent_marking)
DEFINE_NEG_IMPLICATION(disable_write_barriers, cppheap_incremental_marking)
DEFINE_NEG_IMPLICATION(disable_write_barriers, cppheap_concurrent_marking)
#ifdef V8_ENABLE_UNCONDITIONAL_WRITE_BARRIERS
#define V8_ENABLE_UNCONDITIONAL_WRITE_BARRIERS_BOOL true
#else
#define V8_ENABLE_UNCONDITIONAL_WRITE_BARRIERS_BOOL false
#endif
DEFINE_BOOL_READONLY(enable_unconditional_write_barriers,
V8_ENABLE_UNCONDITIONAL_WRITE_BARRIERS_BOOL,
"always use full write barriers")
#ifdef V8_ENABLE_SINGLE_GENERATION
#define V8_SINGLE_GENERATION_BOOL true
#else
#define V8_SINGLE_GENERATION_BOOL false
#endif
DEFINE_BOOL_READONLY(
single_generation, V8_SINGLE_GENERATION_BOOL,
"allocate all objects from young generation to old generation")
#ifdef V8_ENABLE_CONSERVATIVE_STACK_SCANNING
#define V8_ENABLE_CONSERVATIVE_STACK_SCANNING_BOOL true
#else
#define V8_ENABLE_CONSERVATIVE_STACK_SCANNING_BOOL false
#endif
DEFINE_BOOL_READONLY(conservative_stack_scanning,
V8_ENABLE_CONSERVATIVE_STACK_SCANNING_BOOL,
"use conservative stack scanning")
DEFINE_IMPLICATION(conservative_stack_scanning, minor_ms)
DEFINE_NEG_IMPLICATION(conservative_stack_scanning, compact_with_stack)
#ifdef V8_ENABLE_DIRECT_HANDLE
#define V8_ENABLE_DIRECT_HANDLE_BOOL true
#else
#define V8_ENABLE_DIRECT_HANDLE_BOOL false
#endif
DEFINE_BOOL_READONLY(direct_handle, V8_ENABLE_DIRECT_HANDLE_BOOL,
"use direct handles with conservative stack scanning")
// Do not use direct handles without conservative stack scanning, as this would
// break the correctness of the GC.
DEFINE_NEG_NEG_IMPLICATION(conservative_stack_scanning, direct_handle)
#ifdef V8_ENABLE_LOCAL_OFF_STACK_CHECK
#define V8_ENABLE_LOCAL_OFF_STACK_CHECK_BOOL true
#else
#define V8_ENABLE_LOCAL_OFF_STACK_CHECK_BOOL false
#endif
DEFINE_BOOL_READONLY(local_off_stack_check,
V8_ENABLE_LOCAL_OFF_STACK_CHECK_BOOL,
"check for off-stack allocation of v8::Local")
#ifdef V8_ENABLE_FUTURE
#define FUTURE_BOOL true
#else
#define FUTURE_BOOL false
#endif
DEFINE_BOOL(future, FUTURE_BOOL,
"Implies all staged features that we want to ship in the "
"not-too-far future")
DEFINE_BOOL(force_emit_interrupt_budget_checks, false,
"force emit tier-up logic from all non-turbofan code, even if it "
"is the top enabled tier")
#ifdef V8_ENABLE_MAGLEV
DEFINE_BOOL(maglev, true, "enable the maglev optimizing compiler")
#if !ENABLE_MAGLEV
// Enable Maglev on Future for platforms in which it's not enabled by default
// (eg, Android).
DEFINE_WEAK_IMPLICATION(future, maglev)
#endif
DEFINE_EXPERIMENTAL_FEATURE(
maglev_future,
"enable maglev features that we want to ship in the not-too-far future")
DEFINE_IMPLICATION(maglev_future, maglev)
DEFINE_BOOL(
optimize_on_next_call_optimizes_to_maglev, false,
"make OptimizeFunctionOnNextCall optimize to maglev instead of turbofan")
// We stress maglev by setting a very low interrupt budget for maglev. This
// way, we still gather *some* feedback before compiling optimized code.
DEFINE_BOOL(stress_maglev, false, "trigger maglev compilation earlier")
DEFINE_IMPLICATION(stress_maglev, maglev)
DEFINE_WEAK_VALUE_IMPLICATION(stress_maglev, invocation_count_for_maglev, 4)
#else
DEFINE_BOOL_READONLY(maglev, false, "enable the maglev optimizing compiler")
DEFINE_BOOL_READONLY(
maglev_future, false,
"enable maglev features that we want to ship in the not-too-far future")
DEFINE_BOOL_READONLY(stress_maglev, false, "trigger maglev compilation earlier")
DEFINE_BOOL_READONLY(
optimize_on_next_call_optimizes_to_maglev, false,
"make OptimizeFunctionOnNextCall optimize to maglev instead of turbofan")
#endif // V8_ENABLE_MAGLEV
DEFINE_BOOL(maglev_inlining, true,
"enable inlining in the maglev optimizing compiler")
DEFINE_BOOL(maglev_loop_peeling, true,
"enable loop peeling in the maglev optimizing compiler")
DEFINE_BOOL(maglev_optimistic_peeled_loops, false,
"enable speculation on loop state using peeling as fallback in the "
"maglev optimizing compiler")
DEFINE_INT(maglev_loop_peeling_max_size, 200,
"max loop size for loop peeling in the maglev optimizing compiler")
DEFINE_BOOL(maglev_deopt_data_on_background, true,
"Generate deopt data on background thread")
DEFINE_BOOL(maglev_build_code_on_background, true,
"Generate code on background thread")
DEFINE_WEAK_IMPLICATION(maglev_build_code_on_background,
maglev_deopt_data_on_background)
DEFINE_BOOL(maglev_destroy_on_background, true,
"Destroy compilation jobs on background thread")
DEFINE_BOOL(maglev_inline_api_calls, false,
"Inline CallApiCallback builtin into generated code")
DEFINE_EXPERIMENTAL_FEATURE(maglev_licm, "loop invariant code motion")
DEFINE_WEAK_IMPLICATION(maglev_future, maglev_optimistic_peeled_loops)
DEFINE_WEAK_IMPLICATION(maglev_future, maglev_speculative_hoist_phi_untagging)
DEFINE_WEAK_IMPLICATION(maglev_future, maglev_inline_api_calls)
DEFINE_WEAK_IMPLICATION(maglev_future, maglev_escape_analysis)
DEFINE_WEAK_IMPLICATION(maglev_future, maglev_licm)
// This might be too big of a hammer but we must prohibit moving the C++
// trampolines while we are executing a C++ code.
DEFINE_NEG_IMPLICATION(maglev_inline_api_calls, compact_code_space_with_stack)
DEFINE_UINT(
concurrent_maglev_max_threads, 2,
"max number of threads that concurrent Maglev can use (0 for unbounded)")
DEFINE_BOOL(concurrent_maglev_high_priority_threads, false,
"use high priority compiler threads for concurrent Maglev")
DEFINE_INT(
max_maglev_inline_depth, 1,
"max depth of functions that Maglev will inline excl. small functions")
DEFINE_INT(
max_maglev_hard_inline_depth, 10,
"max depth of functions that Maglev will inline incl. small functions")
DEFINE_INT(max_maglev_inlined_bytecode_size, 460,
"maximum size of bytecode for a single inlining")
DEFINE_INT(max_maglev_inlined_bytecode_size_cumulative, 920,
"maximum cumulative size of bytecode considered for inlining excl. "
"small functions")
DEFINE_INT(max_maglev_inlined_bytecode_size_small, 27,
"maximum size of bytecode considered for small function inlining")
DEFINE_FLOAT(min_maglev_inlining_frequency, 0.10,
"minimum frequency for inlining")
DEFINE_WEAK_VALUE_IMPLICATION(turbofan, max_maglev_inline_depth, 1)
DEFINE_WEAK_VALUE_IMPLICATION(turbofan, max_maglev_inlined_bytecode_size, 100)
DEFINE_WEAK_VALUE_IMPLICATION(turbofan,
max_maglev_inlined_bytecode_size_cumulative, 920)
DEFINE_WEAK_VALUE_IMPLICATION(turbofan, min_maglev_inlining_frequency, 0.95)
DEFINE_BOOL(maglev_reuse_stack_slots, true,
"reuse stack slots in the maglev optimizing compiler")
DEFINE_BOOL(maglev_untagged_phis, true,
"enable phi untagging in the maglev optimizing compiler")
DEFINE_BOOL(maglev_hoist_osr_value_phi_untagging, true,
"enable phi untagging to hoist untagging of osr values")
DEFINE_EXPERIMENTAL_FEATURE(
maglev_speculative_hoist_phi_untagging,
"enable phi untagging to hoist untagging of loop phi inputs (could "
"still cause deopt loops)")
DEFINE_BOOL(maglev_cse, true, "common subexpression elimination")
DEFINE_STRING(maglev_filter, "*", "optimization filter for the maglev compiler")
DEFINE_BOOL(maglev_assert, false, "insert extra assertion in maglev code")
DEFINE_DEBUG_BOOL(maglev_assert_stack_size, true,
"insert stack size checks before every IR node")
DEFINE_BOOL(maglev_break_on_entry, false, "insert an int3 on maglev entries")
DEFINE_BOOL(maglev_print_feedback, true,
"print feedback vector for maglev compiled code")
DEFINE_BOOL(maglev_print_inlined, true,
"print bytecode / feedback vectors also for inlined code")
DEFINE_BOOL(print_maglev_code, false, "print maglev code")
DEFINE_BOOL(trace_maglev_graph_building, false, "trace maglev graph building")
DEFINE_BOOL(trace_maglev_loop_speeling, false, "trace maglev loop SPeeling")
DEFINE_WEAK_IMPLICATION(trace_maglev_graph_building, trace_maglev_loop_speeling)
DEFINE_BOOL(trace_maglev_inlining, false, "trace maglev inlining")
DEFINE_BOOL(trace_maglev_inlining_verbose, false,
"trace maglev inlining (verbose)")
DEFINE_IMPLICATION(trace_maglev_inlining_verbose, trace_maglev_inlining)
#ifdef V8_ENABLE_MAGLEV_GRAPH_PRINTER
DEFINE_BOOL(print_maglev_deopt_verbose, false, "print verbose deopt info")
DEFINE_WEAK_IMPLICATION(trace_deopt_verbose, print_maglev_deopt_verbose)
DEFINE_BOOL(print_maglev_graph, false, "print the final maglev graph")
DEFINE_BOOL(print_maglev_graphs, false, "print maglev graph across all phases")
DEFINE_BOOL(trace_maglev_phi_untagging, false, "trace maglev phi untagging")
DEFINE_BOOL(trace_maglev_regalloc, false, "trace maglev register allocation")
#else
DEFINE_BOOL_READONLY(print_maglev_deopt_verbose, false,
"print verbose deopt info")
DEFINE_BOOL_READONLY(print_maglev_graph, false, "print the final maglev graph")
DEFINE_BOOL_READONLY(print_maglev_graphs, false,
"print maglev graph across all phases")
DEFINE_BOOL_READONLY(trace_maglev_phi_untagging, false,
"trace maglev phi untagging")
DEFINE_BOOL_READONLY(trace_maglev_regalloc, false,
"trace maglev register allocation")
#endif // V8_ENABLE_MAGLEV_GRAPH_PRINTER
DEFINE_BOOL(maglev_stats, false, "print Maglev statistics")
DEFINE_BOOL(maglev_stats_nvp, false,
"print Maglev statistics in machine-readable format")
// TODO(v8:7700): Remove once stable.
DEFINE_BOOL(maglev_function_context_specialization, true,
"enable function context specialization in maglev")
DEFINE_BOOL(maglev_skip_migration_check_for_polymorphic_access, false,
"skip generating a migration check when some maps of polymorpic "
"property access are migration targets")
#ifdef V8_ENABLE_SPARKPLUG
DEFINE_WEAK_IMPLICATION(future, flush_baseline_code)
#endif
DEFINE_BOOL(
enable_enumerated_keyed_access_bytecode, true,
"enable generating GetEnumeratedKeyedProperty bytecode for keyed access")
DEFINE_BOOL_READONLY(dict_property_const_tracking,
V8_DICT_PROPERTY_CONST_TRACKING_BOOL,
"Use const tracking on dictionary properties")
DEFINE_BOOL(const_tracking_let, true,
"Use const tracking on top-level `let` variables")
DEFINE_UINT(max_opt, 999,
"Set the maximal optimisation tier: "
"> 3 == any, 0 == ignition/interpreter, 1 == sparkplug/baseline, "
"2 == maglev, 3 == turbofan")
#ifdef V8_ENABLE_TURBOFAN
DEFINE_WEAK_VALUE_IMPLICATION(max_opt < 3, turbofan, false)
#endif // V8_ENABLE_TURBOFAN
#ifdef V8_ENABLE_MAGLEV
DEFINE_WEAK_VALUE_IMPLICATION(max_opt < 2, maglev, false)
#endif // V8_ENABLE_MAGLEV
#ifdef V8_ENABLE_SPARKPLUG
DEFINE_WEAK_VALUE_IMPLICATION(max_opt < 1, sparkplug, false)
#endif // V8_ENABLE_SPARKPLUG
// Flags to override efficiency and battery saver mode settings for debugging
// and testing.
DEFINE_MAYBE_BOOL(efficiency_mode,
"Forces efficiency mode on or off, disregarding any dynamic "
"signals. Efficiency mode is optimized for situations with "
"no latency requirements and uses fewer threads.")
DEFINE_MAYBE_BOOL(
battery_saver_mode,
"Forces battery saver mode on or off, disregarding any dynamic signals. "
"Battery saver tries to conserve overal cpu cycles spent.")
// Flags to experiment with the new efficiency mode
DEFINE_BOOL(efficiency_mode_for_tiering_heuristics, true,
"Use efficiency mode in tiering heuristics.")
DEFINE_BOOL(efficiency_mode_disable_turbofan, false,
"Defer tier-up to turbofan while in efficiency mode.")
DEFINE_INT(efficiency_mode_delay_turbofan, 15000,
"Delay tier-up to turbofan to a certain invocation count while in "
"efficiency mode.")
// Flag to select wasm trace mark type
DEFINE_STRING(
wasm_trace_native, nullptr,
"Select which native code sequence to use for wasm trace instruction: "
"default or cpuid")
#ifdef V8_JITLESS
#define V8_JITLESS_BOOL true
DEFINE_BOOL_READONLY(jitless, true,
"Disable runtime allocation of executable memory.")
#else
#define V8_JITLESS_BOOL false
DEFINE_BOOL(jitless, V8_LITE_MODE_BOOL,
"Disable runtime allocation of executable memory.")
#endif // V8_JITLESS
// Jitless V8 has a few implications:
// Field type tracking is only used by TurboFan.
DEFINE_NEG_IMPLICATION(jitless, track_field_types)
// No code generation at runtime.
DEFINE_IMPLICATION(jitless, regexp_interpret_all)
DEFINE_NEG_IMPLICATION(jitless, turbofan)
#ifdef V8_ENABLE_SPARKPLUG
DEFINE_NEG_IMPLICATION(jitless, sparkplug)
DEFINE_NEG_IMPLICATION(jitless, always_sparkplug)
#endif // V8_ENABLE_SPARKPLUG
#ifdef V8_ENABLE_MAGLEV
DEFINE_NEG_IMPLICATION(jitless, maglev)
#endif // V8_ENABLE_MAGLEV
// Doesn't work without an executable code space.
DEFINE_NEG_IMPLICATION(jitless, interpreted_frames_native_stack)
DEFINE_BOOL(
disable_optimizing_compilers, false,
"Disable all optimizing compilers while leaving baseline compilers enabled")
// Disable all optimizing JavaScript compilers.
// JavaScript code can execute either in Ignition or Sparkplug.
DEFINE_NEG_IMPLICATION(disable_optimizing_compilers, turbofan)
DEFINE_NEG_IMPLICATION(disable_optimizing_compilers, turboshaft)
DEFINE_NEG_IMPLICATION(disable_optimizing_compilers, maglev)
#if V8_ENABLE_WEBASSEMBLY
// Disable optimizing Wasm compilers. Wasm code must execute with Liftoff.
DEFINE_IMPLICATION(disable_optimizing_compilers, liftoff)
DEFINE_NEG_IMPLICATION(disable_optimizing_compilers, wasm_tier_up)
DEFINE_NEG_IMPLICATION(disable_optimizing_compilers, wasm_dynamic_tiering)
// Disable translation of asm.js to Wasm
DEFINE_NEG_IMPLICATION(disable_optimizing_compilers, validate_asm)
#endif // V8_ENABLE_WEBASSEMBLY
// Field type tracking is only used by TurboFan, so can be disabled.
DEFINE_NEG_IMPLICATION(disable_optimizing_compilers, track_field_types)
DEFINE_BOOL(memory_protection_keys, true,
"protect code memory with PKU if available")
DEFINE_BOOL(assert_types, false,
"generate runtime type assertions to test the typer")
// TODO(tebbi): Support allocating types from background thread.
DEFINE_NEG_IMPLICATION(assert_types, concurrent_recompilation)
DEFINE_EXPERIMENTAL_FEATURE(
turboshaft_assert_types,
"generate runtime type assertions to test the turboshaft type system")
DEFINE_NEG_IMPLICATION(turboshaft_assert_types, concurrent_recompilation)
// Enable verification of SimplifiedLowering in debug builds.
DEFINE_BOOL(verify_simplified_lowering, DEBUG_BOOL,
"verify graph generated by simplified lowering")
DEFINE_BOOL(trace_compilation_dependencies, false, "trace code dependencies")
// Depend on --trace-deopt-verbose for reporting dependency invalidations.
DEFINE_IMPLICATION(trace_compilation_dependencies, trace_deopt_verbose)
#ifdef V8_ALLOCATION_SITE_TRACKING
#define V8_ALLOCATION_SITE_TRACKING_BOOL true
#else
#define V8_ALLOCATION_SITE_TRACKING_BOOL false
#endif
DEFINE_BOOL_READONLY(allocation_site_tracking, V8_ALLOCATION_SITE_TRACKING_BOOL,
"Enable allocation site tracking")
DEFINE_NEG_NEG_IMPLICATION(allocation_site_tracking,
allocation_site_pretenuring)
// Flags for experimental implementation features.
DEFINE_BOOL(allocation_site_pretenuring, true,
"pretenure with allocation sites")
DEFINE_BOOL(page_promotion, true, "promote pages based on utilization")
DEFINE_INT(page_promotion_threshold, 70,
"min percentage of live bytes on a page to enable fast evacuation "
"in full GCs")
DEFINE_INT(minor_ms_page_promotion_threshold, 50,
"min percentage of live bytes on a page to enable fast evacuation "
"in MinorMS")
DEFINE_INT(minor_ms_page_promotion_max_lab_threshold, 30,
"max percentage of labs out of a page to still be considered for "
"page promotion")
DEFINE_UINT(minor_ms_max_page_age, 4,
"max age for a page after which it is force promoted to old space")
DEFINE_UINT(minor_ms_max_new_space_capacity_mb, 72,
"max new space capacity in MBs when using MinorMS. When pointer "
"compression is disabled, twice the capacity is used.")
DEFINE_UINT(scavenger_max_new_space_capacity_mb, 8,
"max new space capacity in MBs when using Scavenger. When pointer "
"compression is disabled, twice the capacity is used.")
DEFINE_BOOL(trace_page_promotions, false, "trace page promotion decisions")
DEFINE_BOOL(trace_pretenuring, false,
"trace pretenuring decisions of HAllocate instructions")
DEFINE_BOOL(trace_pretenuring_statistics, false,
"trace allocation site pretenuring statistics")
DEFINE_BOOL(track_field_types, true, "track field types")
DEFINE_BOOL(trace_block_coverage, false,
"trace collected block coverage information")
DEFINE_BOOL(trace_protector_invalidation, false,
"trace protector cell invalidations")
DEFINE_BOOL(decommit_pooled_pages, false,
"decommit, rather than discard pooled pages")
#ifdef V8_MINORMS_STRING_SHORTCUTTING
DEFINE_BOOL(minor_ms_shortcut_strings, false,
"short cut strings during marking")
// String shortcutting currently doesn't work with concurrent marking.
DEFINE_NEG_IMPLICATION(minor_ms_shortcut_strings, concurrent_minor_ms_marking)
#else
DEFINE_BOOL_READONLY(minor_ms_shortcut_strings, false,
"short cut strings during marking")
#endif
DEFINE_EXPERIMENTAL_FEATURE(feedback_normalization,
"feed back normalization to constructors")
// TODO(jkummerow): This currently adds too much load on the stub cache.
DEFINE_BOOL_READONLY(internalize_on_the_fly, true,
"internalize string keys for generic keyed ICs on the fly")
// Flag for sealed, frozen elements kind instead of dictionary elements kind
DEFINE_BOOL_READONLY(enable_sealed_frozen_elements_kind, true,
"Enable sealed, frozen elements kind")
// Flags for data representation optimizations
DEFINE_BOOL(unbox_double_arrays, true, "automatically unbox arrays of doubles")
DEFINE_BOOL_READONLY(string_slices, true, "use string slices")
// Tiering: Sparkplug / feedback vector allocation.
DEFINE_INT(invocation_count_for_feedback_allocation, 8,
"invocation count required for allocating feedback vectors")
// Tiering: Maglev.
#if defined(ANDROID)
DEFINE_INT(invocation_count_for_maglev, 1000,
"invocation count required for optimizing with Maglev")
#else
DEFINE_INT(invocation_count_for_maglev, 400,
"invocation count required for optimizing with Maglev")
#endif // ANDROID
DEFINE_INT(invocation_count_for_maglev_osr, 100,
"invocation count required for maglev OSR")
DEFINE_BOOL(osr_from_maglev, false,
"whether we try to OSR to Turbofan from OSR'd Maglev")
DEFINE_FLOAT(
osr_from_maglev_interrupt_scale_factor, 0.8,
"Scale interrupt budget reduction for OSR from Maglev vs. OSR to Maglev")
DEFINE_BOOL(always_osr_from_maglev, false,
"whether we try to OSR to Turbofan from any Maglev")
DEFINE_VALUE_IMPLICATION(always_osr_from_maglev, osr_from_maglev, true)
// Tiering: Turbofan.
DEFINE_INT(invocation_count_for_turbofan, 3000,
"invocation count required for optimizing with TurboFan")
DEFINE_INT(invocation_count_for_osr, 500, "invocation count required for OSR")
DEFINE_INT(osr_to_tierup, 1,
"number to decrease the invocation budget by when we follow OSR")
DEFINE_INT(minimum_invocations_after_ic_update, 500,
"How long to minimally wait after IC update before tier up")
DEFINE_INT(minimum_invocations_before_optimization, 2,
"Minimum number of invocations we need before non-OSR optimization")
// Tiering: JIT fuzzing.
//
// When --jit-fuzzing is enabled, various tiering related thresholds are
// lowered so that the different JIT tiers are reached roughly within a few
// dozen executions of the code instead of a few hundred or thousand. As a rule
// of thumb, aiming for things to happen 5x to 10x sooner in this mode than
// they otherwise would is probably not unreasonable.
DEFINE_BOOL(jit_fuzzing, false,
"Set JIT tiering thresholds suitable for JIT fuzzing")
// Tier up to Sparkplug should happen after a handful o executions in ignition.
DEFINE_NEG_IMPLICATION(jit_fuzzing, lazy_feedback_allocation)
DEFINE_NEG_IMPLICATION(jit_fuzzing, baseline_batch_compilation)
// Tier up to Maglev should happen soon afterwards.
DEFINE_VALUE_IMPLICATION(jit_fuzzing, invocation_count_for_maglev, 10)
// And tier up to Turbofan should happen after a couple dozen or so executions.
DEFINE_VALUE_IMPLICATION(jit_fuzzing, invocation_count_for_turbofan, 20)
// Additionally, some other JIT-related thresholds should also be lowered.
DEFINE_VALUE_IMPLICATION(jit_fuzzing, invocation_count_for_osr, 5)
DEFINE_VALUE_IMPLICATION(jit_fuzzing, invocation_count_for_maglev_osr, 1)
DEFINE_VALUE_IMPLICATION(jit_fuzzing, minimum_invocations_after_ic_update, 5)
#if V8_ENABLE_WEBASSEMBLY
// Wasm tiering thresholds.
DEFINE_VALUE_IMPLICATION(jit_fuzzing, wasm_wrapper_tiering_budget, 1)
DEFINE_VALUE_IMPLICATION(jit_fuzzing, wasm_tiering_budget, 1)
DEFINE_IMPLICATION(jit_fuzzing, wasm_inlining_ignore_call_counts)
#endif // V8_ENABLE_WEBASSEMBLY
// Flags for inline caching and feedback vectors.
DEFINE_BOOL(use_ic, true, "use inline caching")
DEFINE_BOOL(lazy_feedback_allocation, true, "Allocate feedback vectors lazily")
DEFINE_BOOL(stress_ic, false, "exercise interesting paths in ICs more often")
// Flags for Ignition.
DEFINE_BOOL(ignition_elide_noneffectful_bytecodes, true,
"elide bytecodes which won't have any external effect")
DEFINE_BOOL(ignition_reo, true, "use ignition register equivalence optimizer")
DEFINE_BOOL(ignition_filter_expression_positions, true,
"filter expression positions before the bytecode pipeline")
DEFINE_BOOL(ignition_share_named_property_feedback, true,
"share feedback slots when loading the same named property from "
"the same object")
DEFINE_BOOL(ignition_elide_redundant_tdz_checks, true,
"elide TDZ checks dominated by other TDZ checks")
DEFINE_BOOL(print_bytecode, false,
"print bytecode generated by ignition interpreter")
DEFINE_BOOL(enable_lazy_source_positions, V8_LAZY_SOURCE_POSITIONS_BOOL,
"skip generating source positions during initial compile but "
"regenerate when actually required")
DEFINE_BOOL(stress_lazy_source_positions, false,
"collect lazy source positions immediately after lazy compile")
DEFINE_STRING(print_bytecode_filter, "*",
"filter for selecting which functions to print bytecode")
DEFINE_BOOL(omit_default_ctors, true, "omit calling default ctors in bytecode")
#ifdef V8_TRACE_UNOPTIMIZED
DEFINE_BOOL(trace_unoptimized, false,
"trace the bytecodes executed by all unoptimized execution")
DEFINE_BOOL(trace_ignition, false,
"trace the bytecodes executed by the ignition interpreter")
DEFINE_BOOL(trace_baseline_exec, false,
"trace the bytecodes executed by the baseline code")
DEFINE_WEAK_IMPLICATION(trace_unoptimized, trace_ignition)
DEFINE_WEAK_IMPLICATION(trace_unoptimized, trace_baseline_exec)
#endif
#ifdef V8_TRACE_FEEDBACK_UPDATES
DEFINE_BOOL(
trace_feedback_updates, false,
"trace updates to feedback vectors during ignition interpreter execution.")
#endif
DEFINE_BOOL(trace_ignition_codegen, false,
"trace the codegen of ignition interpreter bytecode handlers")
DEFINE_STRING(
trace_ignition_dispatches_output_file, nullptr,
"write the bytecode handler dispatch table to the specified file (d8 only) "
"(requires building with v8_enable_ignition_dispatch_counting)")
DEFINE_BOOL(trace_track_allocation_sites, false,
"trace the tracking of allocation sites")
DEFINE_BOOL(trace_migration, false, "trace object migration")
DEFINE_BOOL(trace_generalization, false, "trace map generalization")
DEFINE_BOOL(reuse_scope_infos, false,
"reuse scope infos from previous compiles")
DEFINE_IMPLICATION(fuzzing, reuse_scope_infos)
// Flags for Sparkplug
#undef FLAG
#if V8_ENABLE_SPARKPLUG
#define FLAG FLAG_FULL
#else
#define FLAG FLAG_READONLY
#endif
DEFINE_BOOL(sparkplug, ENABLE_SPARKPLUG_BY_DEFAULT,
"enable Sparkplug baseline compiler")