--use_strict (enforce strict mode)
type: bool default: false
- --es5_readonly (activate correct semantics for inheriting readonliness)
+ --es_staging (enable all completed harmony features)
type: bool default: false
- --es52_globals (activate new semantics for global var declarations)
+ --harmony (enable all completed harmony features)
type: bool default: false
- --harmony_typeof (enable harmony semantics for typeof)
+ --harmony_shipping (enable all shipped harmony fetaures)
+ type: bool default: true
+ --harmony_modules (enable "harmony modules (implies block scoping)" (in progress))
+ type: bool default: false
+ --harmony_arrays (enable "harmony array methods" (in progress))
+ type: bool default: false
+ --harmony_array_includes (enable "harmony Array.prototype.includes" (in progress))
+ type: bool default: false
+ --harmony_regexps (enable "harmony regular expression extensions" (in progress))
+ type: bool default: false
+ --harmony_arrow_functions (enable "harmony arrow functions" (in progress))
+ type: bool default: false
+ --harmony_proxies (enable "harmony proxies" (in progress))
type: bool default: false
- --harmony_scoping (enable harmony block scoping)
+ --harmony_sloppy (enable "harmony features in sloppy mode" (in progress))
type: bool default: false
- --harmony_modules (enable harmony modules (implies block scoping))
+ --harmony_unicode (enable "harmony unicode escapes" (in progress))
type: bool default: false
- --harmony_proxies (enable harmony proxies)
+ --harmony_tostring (enable "harmony toString")
+ type: bool default: false
+ --harmony_numeric_literals (enable "harmony numeric literals")
+ type: bool default: true
+ --harmony_strings (enable "harmony string methods")
+ type: bool default: true
+ --harmony_scoping (enable "harmony block scoping")
+ type: bool default: true
+ --harmony_classes (enable "harmony classes (implies block scoping & object literal extension)")
+ type: bool default: true
+ --harmony_object_literals (enable "harmony object literal extensions")
+ type: bool default: true
+ --harmony_templates (enable "harmony template literals")
+ type: bool default: true
+ --compiled_keyed_generic_loads (use optimizing compiler to generate keyed generic load stubs)
type: bool default: false
- --harmony_collections (enable harmony collections (sets, maps, and weak maps))
+ --pretenuring_call_new (pretenure call new)
type: bool default: false
- --harmony (enable all harmony features (except typeof))
+ --allocation_site_pretenuring (pretenure with allocation sites)
+ type: bool default: true
+ --trace_pretenuring (trace pretenuring decisions of HAllocate instructions)
type: bool default: false
- --packed_arrays (optimizes arrays that have no holes)
+ --trace_pretenuring_statistics (trace allocation site pretenuring statistics)
type: bool default: false
- --smi_only_arrays (tracks arrays with only smi values)
+ --track_fields (track fields with only smi values)
+ type: bool default: true
+ --track_double_fields (track fields with double values)
+ type: bool default: true
+ --track_heap_object_fields (track fields with heap values)
+ type: bool default: true
+ --track_computed_fields (track computed boilerplate fields)
type: bool default: true
- --clever_optimizations (Optimize object size, Array shift, DOM strings and string +)
+ --track_field_types (track field types)
type: bool default: true
+ --smi_binop (support smi representation in binary operations)
+ type: bool default: true
+ --vector_ics (support vector-based ics)
+ type: bool default: false
+ --optimize_for_size (Enables optimizations which favor memory size over execution speed.)
+ type: bool default: false
--unbox_double_arrays (automatically unbox arrays of doubles)
type: bool default: true
--string_slices (use string slices)
--crankshaft (use crankshaft)
type: bool default: true
--hydrogen_filter (optimization filter)
- type: string default:
- --use_range (use hydrogen range analysis)
- type: bool default: true
- --eliminate_dead_phis (eliminate dead phis)
- type: bool default: true
+ type: string default: *
--use_gvn (use hydrogen global value numbering)
type: bool default: true
+ --gvn_iterations (maximum number of GVN fix-point iterations)
+ type: int default: 3
--use_canonicalizing (use hydrogen instruction canonicalizing)
type: bool default: true
--use_inlining (use function inlining)
type: bool default: true
+ --use_escape_analysis (use hydrogen escape analysis)
+ type: bool default: true
+ --use_allocation_folding (use allocation folding)
+ type: bool default: true
+ --use_local_allocation_folding (only fold in basic blocks)
+ type: bool default: false
+ --use_write_barrier_elimination (eliminate write barriers targeting allocations in optimized code)
+ type: bool default: true
+ --max_inlining_levels (maximum number of inlining levels)
+ type: int default: 5
--max_inlined_source_size (maximum source size in bytes considered for a single inlining)
type: int default: 600
--max_inlined_nodes (maximum number of AST nodes considered for a single inlining)
type: int default: 196
--max_inlined_nodes_cumulative (maximum cumulative number of AST nodes considered for inlining)
- type: int default: 196
+ type: int default: 400
--loop_invariant_code_motion (loop invariant code motion)
type: bool default: true
+ --fast_math (faster (but maybe less accurate) math functions)
+ type: bool default: true
--collect_megamorphic_maps_from_stub_cache (crankshaft harvests type feedback from stub cache)
type: bool default: true
--hydrogen_stats (print statistics for hydrogen)
type: bool default: false
+ --trace_check_elimination (trace check elimination phase)
+ type: bool default: false
--trace_hydrogen (trace generated hydrogen to file)
type: bool default: false
+ --trace_hydrogen_filter (hydrogen tracing filter)
+ type: string default: *
+ --trace_hydrogen_stubs (trace generated hydrogen for stubs)
+ type: bool default: false
+ --trace_hydrogen_file (trace hydrogen to given file name)
+ type: string default: NULL
--trace_phase (trace generated IR for specified phases)
- type: string default: Z
+ type: string default: HLZ
--trace_inlining (trace inlining decisions)
type: bool default: false
+ --trace_load_elimination (trace load elimination)
+ type: bool default: false
+ --trace_store_elimination (trace store elimination)
+ type: bool default: false
--trace_alloc (trace register allocator)
type: bool default: false
--trace_all_uses (trace all use positions)
type: bool default: false
--trace_representation (trace representation types)
type: bool default: false
+ --trace_removable_simulates (trace removable simulates)
+ type: bool default: false
+ --trace_escape_analysis (trace hydrogen escape analysis)
+ type: bool default: false
+ --trace_allocation_folding (trace allocation folding)
+ type: bool default: false
+ --trace_track_allocation_sites (trace the tracking of allocation sites)
+ type: bool default: false
+ --trace_migration (trace object migration)
+ type: bool default: false
+ --trace_generalization (trace map generalization)
+ type: bool default: false
--stress_pointer_maps (pointer map for every instruction)
type: bool default: false
--stress_environments (environment for every instruction)
type: bool default: false
--deopt_every_n_times (deoptimize every n times a deopt point is passed)
type: int default: 0
+ --deopt_every_n_garbage_collections (deoptimize every n garbage collections)
+ type: int default: 0
+ --print_deopt_stress (print number of possible deopt points)
+ type: bool default: false
--trap_on_deopt (put a break point before deoptimizing)
type: bool default: false
+ --trap_on_stub_deopt (put a break point before deoptimizing a stub)
+ type: bool default: false
--deoptimize_uncommon_cases (deoptimize uncommon cases)
type: bool default: true
--polymorphic_inlining (polymorphic inlining)
--use_osr (use on-stack replacement)
type: bool default: true
--array_bounds_checks_elimination (perform array bounds checks elimination)
+ type: bool default: true
+ --trace_bce (trace array bounds check elimination)
+ type: bool default: false
+ --array_bounds_checks_hoisting (perform array bounds checks hoisting)
type: bool default: false
--array_index_dehoisting (perform array index dehoisting)
+ type: bool default: true
+ --analyze_environment_liveness (analyze liveness of environment slots and zap dead values)
+ type: bool default: true
+ --load_elimination (use load elimination)
+ type: bool default: true
+ --check_elimination (use check elimination)
+ type: bool default: true
+ --store_elimination (use store elimination)
type: bool default: false
+ --dead_code_elimination (use dead code elimination)
+ type: bool default: true
+ --fold_constants (use constant folding)
+ type: bool default: true
+ --trace_dead_code_elimination (trace dead code elimination)
+ type: bool default: false
+ --unreachable_code_elimination (eliminate unreachable code)
+ type: bool default: true
--trace_osr (trace on-stack replacement)
type: bool default: false
--stress_runs (number of stress runs)
type: int default: 0
- --optimize_closures (optimize closures)
+ --lookup_sample_by_shared (when picking a function to optimize, watch for shared function info, not JSFunction itself)
+ type: bool default: true
+ --cache_optimized_code (cache optimized code for closures)
+ type: bool default: true
+ --flush_optimized_code_cache (flushes the cache of optimized code for closures on every GC)
type: bool default: true
--inline_construct (inline constructor calls)
type: bool default: true
--inline_arguments (inline functions with arguments object)
type: bool default: true
- --loop_weight (loop weight for representation inference)
- type: int default: 1
+ --inline_accessors (inline JavaScript accessors)
+ type: bool default: true
+ --escape_analysis_iterations (maximum number of escape analysis fix-point iterations)
+ type: int default: 2
--optimize_for_in (optimize functions containing for-in loops)
type: bool default: true
- --experimental_profiler (enable all profiler experiments)
+ --concurrent_recompilation (optimizing hot functions asynchronously on a separate thread)
type: bool default: true
- --watch_ic_patching (profiler considers IC stability)
+ --job_based_recompilation (post tasks to v8::Platform instead of using a thread for concurrent recompilation)
type: bool default: false
- --frame_count (number of stack frames inspected by the profiler)
- type: int default: 1
- --self_optimization (primitive functions trigger their own optimization)
+ --trace_concurrent_recompilation (track concurrent recompilation)
type: bool default: false
- --direct_self_opt (call recompile stub directly when self-optimizing)
+ --concurrent_recompilation_queue_length (the length of the concurrent compilation queue)
+ type: int default: 8
+ --concurrent_recompilation_delay (artificial compilation delay in ms)
+ type: int default: 0
+ --block_concurrent_recompilation (block queued jobs until released)
type: bool default: false
- --retry_self_opt (re-try self-optimization if it failed)
+ --concurrent_osr (concurrent on-stack replacement)
+ type: bool default: true
+ --omit_map_checks_for_leaf_maps (do not emit check maps for constant values that have a leaf map, deoptimize the optimized code if the layout of the maps changes.)
+ type: bool default: true
+ --turbo_filter (optimization filter for TurboFan compiler)
+ type: string default: ~
+ --trace_turbo (trace generated TurboFan IR)
+ type: bool default: false
+ --trace_turbo_graph (trace generated TurboFan graphs)
type: bool default: false
- --count_based_interrupts (trigger profiler ticks based on counting instead of timing)
+ --trace_turbo_cfg_file (trace turbo cfg graph (for C1 visualizer) to a given file name)
+ type: string default: NULL
+ --trace_turbo_types (trace TurboFan's types)
+ type: bool default: true
+ --trace_turbo_scheduler (trace TurboFan's scheduler)
type: bool default: false
- --interrupt_at_exit (insert an interrupt check at function exit)
+ --trace_turbo_reduction (trace TurboFan's various reducers)
type: bool default: false
- --weighted_back_edges (weight back edges by jump distance for interrupt triggering)
+ --trace_turbo_jt (trace TurboFan's jump threading)
type: bool default: false
+ --turbo_asm (enable TurboFan for asm.js code)
+ type: bool default: true
+ --turbo_verify (verify TurboFan graphs at each phase)
+ type: bool default: false
+ --turbo_stats (print TurboFan statistics)
+ type: bool default: false
+ --turbo_types (use typed lowering in TurboFan)
+ type: bool default: true
+ --turbo_source_positions (track source code positions when building TurboFan IR)
+ type: bool default: false
+ --context_specialization (enable context specialization in TurboFan)
+ type: bool default: false
+ --turbo_deoptimization (enable deoptimization in TurboFan)
+ type: bool default: false
+ --turbo_inlining (enable inlining in TurboFan)
+ type: bool default: false
+ --turbo_inlining_intrinsics (enable inlining of intrinsics in TurboFan)
+ type: bool default: false
+ --trace_turbo_inlining (trace TurboFan inlining)
+ type: bool default: false
+ --loop_assignment_analysis (perform loop assignment analysis)
+ type: bool default: true
+ --turbo_profiling (enable profiling in TurboFan)
+ type: bool default: false
+ --turbo_reuse_spill_slots (reuse spill slots in TurboFan)
+ type: bool default: true
+ --turbo_delay_ssa_decon (delay ssa deconstruction in TurboFan register allocator)
+ type: bool default: false
+ --turbo_move_optimization (optimize gap moves in TurboFan)
+ type: bool default: true
+ --turbo_jt (enable jump threading)
+ type: bool default: true
+ --typed_array_max_size_in_heap (threshold for in-heap typed array)
+ type: int default: 64
+ --frame_count (number of stack frames inspected by the profiler)
+ type: int default: 1
--interrupt_budget (execution budget before interrupt is triggered)
- type: int default: 5900
+ type: int default: 6144
--type_info_threshold (percentage of ICs that must have type info to allow optimization)
- type: int default: 15
+ type: int default: 25
+ --generic_ic_threshold (max percentage of megamorphic/generic ICs to allow optimization)
+ type: int default: 30
--self_opt_count (call count before self-optimization)
type: int default: 130
--trace_opt_verbose (extra verbose compilation tracing)
type: bool default: false
--code_comments (emit comments in code disassembly)
type: bool default: false
- --enable_sse2 (enable use of SSE2 instructions if available)
- type: bool default: true
--enable_sse3 (enable use of SSE3 instructions if available)
type: bool default: true
--enable_sse4_1 (enable use of SSE4.1 instructions if available)
type: bool default: true
- --enable_cmov (enable use of CMOV instruction if available)
+ --enable_sahf (enable use of SAHF instruction if available (X64 only))
type: bool default: true
- --enable_rdtsc (enable use of RDTSC instruction if available)
+ --enable_avx (enable use of AVX instructions if available)
type: bool default: true
- --enable_sahf (enable use of SAHF instruction if available (X64 only))
+ --enable_fma3 (enable use of FMA3 instructions if available)
type: bool default: true
- --enable_vfp3 (enable use of VFP3 instructions if available - this implies enabling ARMv7 instructions (ARM only))
+ --enable_vfp3 (enable use of VFP3 instructions if available)
type: bool default: true
--enable_armv7 (enable use of ARMv7 instructions if available (ARM only))
type: bool default: true
- --enable_fpu (enable use of MIPS FPU instructions if available (MIPS only))
+ --enable_armv8 (enable use of ARMv8 instructions if available (ARM 32-bit only))
type: bool default: true
+ --enable_neon (enable use of NEON instructions if available (ARM only))
+ type: bool default: true
+ --enable_sudiv (enable use of SDIV and UDIV instructions if available (ARM only))
+ type: bool default: true
+ --enable_mls (enable use of MLS instructions if available (ARM only))
+ type: bool default: true
+ --enable_movw_movt (enable loading 32-bit constant by means of movw/movt instruction pairs (ARM only))
+ type: bool default: false
+ --enable_unaligned_accesses (enable unaligned accesses for ARMv7 (ARM only))
+ type: bool default: true
+ --enable_32dregs (enable use of d16-d31 registers on ARM - this requires VFP3)
+ type: bool default: true
+ --enable_vldr_imm (enable use of constant pools for double immediate (ARM only))
+ type: bool default: false
+ --force_long_branches (force all emitted branches to be in long mode (MIPS only))
+ type: bool default: false
--expose_natives_as (expose natives in global object)
type: string default: NULL
--expose_debug_as (expose debug in global object)
type: string default: NULL
+ --expose_free_buffer (expose freeBuffer extension)
+ type: bool default: false
--expose_gc (expose gc extension)
type: bool default: false
+ --expose_gc_as (expose gc extension under the specified name)
+ type: string default: NULL
--expose_externalize_string (expose externalize string extension)
type: bool default: false
+ --expose_trigger_failure (expose trigger-failure extension)
+ type: bool default: false
--stack_trace_limit (number of stack frames to capture)
type: int default: 10
--builtins_in_stack_traces (show built-in functions in stack traces)
type: bool default: false
--inline_new (use fast inline allocation)
type: bool default: true
- --stack_trace_on_abort (print a stack trace if an assertion failure occurs)
- type: bool default: true
+ --trace_codegen (print name of functions for which code is generated)
+ type: bool default: false
--trace (trace function calls)
type: bool default: false
--mask_constants_with_cookie (use random jit cookie to mask large constants)
type: bool default: true
--always_opt (always try to optimize functions)
type: bool default: false
+ --always_osr (always try to OSR functions)
+ type: bool default: false
--prepare_always_opt (prepare for turning on always opt)
type: bool default: false
- --trace_deopt (trace deoptimization)
+ --trace_deopt (trace optimize function deoptimization)
type: bool default: false
- --min_preparse_length (minimum length for automatic enable preparsing)
- type: int default: 1024
- --always_full_compiler (try to use the dedicated run-once backend for all code)
+ --trace_stub_failures (trace deoptimization of generated code stubs)
type: bool default: false
- --trace_bailout (print reasons for falling back to using the classic V8 backend)
+ --serialize_toplevel (enable caching of toplevel scripts)
+ type: bool default: true
+ --serialize_inner (enable caching of inner functions)
type: bool default: false
+ --trace_serializer (print code serializer trace)
+ type: bool default: false
+ --min_preparse_length (minimum length for automatic enable preparsing)
+ type: int default: 1024
+ --max_opt_count (maximum number of optimization attempts before giving up.)
+ type: int default: 10
--compilation_cache (enable compilation cache)
type: bool default: true
--cache_prototype_transitions (cache prototype transitions)
type: bool default: true
+ --cpu_profiler_sampling_interval (CPU profiler sampling interval in microseconds)
+ type: int default: 1000
--trace_debug_json (trace debugging JSON request/response)
type: bool default: false
- --debugger_auto_break (automatically set the debug break flag when debugger commands are in the queue)
- type: bool default: true
+ --trace_js_array_abuse (trace out-of-bounds accesses to JS arrays)
+ type: bool default: false
+ --trace_external_array_abuse (trace out-of-bounds-accesses to external arrays)
+ type: bool default: false
+ --trace_array_abuse (trace out-of-bounds accesses to all arrays)
+ type: bool default: false
--enable_liveedit (enable liveedit experimental feature)
type: bool default: true
- --break_on_abort (always cause a debug break before aborting)
+ --hard_abort (abort by crashing)
type: bool default: true
--stack_size (default size of stack region v8 is allowed to use (in kBytes))
type: int default: 984
type: int default: 300
--always_inline_smi_code (always inline smi code in non-opt code)
type: bool default: false
- --max_new_space_size (max size of the new generation (in kBytes))
+ --min_semi_space_size (min size of a semi-space (in MBytes), the new space consists of twosemi-spaces)
type: int default: 0
- --max_old_space_size (max size of the old generation (in Mbytes))
+ --target_semi_space_size (target size of a semi-space (in MBytes) before triggering a GC)
+ type: int default: 0
+ --max_semi_space_size (max size of a semi-space (in MBytes), the new space consists of twosemi-spaces)
+ type: int default: 0
+ --semi_space_growth_factor (factor by which to grow the new space)
+ type: int default: 2
+ --experimental_new_space_growth_heuristic (Grow the new space based on the percentage of survivors instead of their absolute value.)
+ type: bool default: false
+ --max_old_space_size (max size of the old space (in Mbytes))
+ type: int default: 0
+ --initial_old_space_size (initial old space size (in Mbytes))
type: int default: 0
--max_executable_size (max size of executable memory (in Mbytes))
type: int default: 0
type: bool default: false
--trace_gc_nvp (print one detailed trace line in name=value format after each garbage collection)
type: bool default: false
+ --trace_gc_ignore_scavenger (do not print trace line after scavenger collection)
+ type: bool default: false
+ --trace_idle_notification (print one trace line following each idle notification)
+ type: bool default: false
+ --trace_idle_notification_verbose (prints the heap state used by the idle notification)
+ type: bool default: false
--print_cumulative_gc_stat (print cumulative GC statistics in name=value format on exit)
type: bool default: false
+ --print_max_heap_committed (print statistics of the maximum memory committed for the heap in name=value format on exit)
+ type: bool default: false
--trace_gc_verbose (print more details following each garbage collection)
type: bool default: false
--trace_fragmentation (report fragmentation for old pointer and data pages)
type: bool default: false
--collect_maps (garbage collect maps from which no objects can be reached)
type: bool default: true
- --flush_code (flush code that we expect not to use again before full gc)
+ --weak_embedded_maps_in_optimized_code (make maps embedded in optimized code weak)
+ type: bool default: true
+ --weak_embedded_objects_in_optimized_code (make objects embedded in optimized code weak)
+ type: bool default: true
+ --flush_code (flush code that we expect not to use again (during full gc))
+ type: bool default: true
+ --flush_code_incrementally (flush code that we expect not to use again (incrementally))
+ type: bool default: true
+ --trace_code_flushing (trace code flushing progress)
+ type: bool default: false
+ --age_code (track un-executed functions to age code and flush only old code (required for code flushing))
type: bool default: true
--incremental_marking (use incremental marking)
type: bool default: true
--incremental_marking_steps (do incremental marking steps)
type: bool default: true
+ --concurrent_sweeping (use concurrent sweeping)
+ type: bool default: true
--trace_incremental_marking (trace progress of the incremental marking)
type: bool default: false
+ --track_gc_object_stats (track object counts and memory usage)
+ type: bool default: false
+ --heap_profiler_trace_objects (Dump heap object allocations/movements/size_updates)
+ type: bool default: false
--use_idle_notification (Use idle notification to reduce memory footprint.)
type: bool default: true
- --send_idle_notification (Send idle notification between stress runs.)
- type: bool default: false
--use_ic (use inline caching)
type: bool default: true
+ --trace_ic (trace inline cache state transitions)
+ type: bool default: false
--native_code_counters (generate extra code for manipulating stats counters)
type: bool default: false
--always_compact (Perform compaction on every full GC)
type: bool default: false
- --lazy_sweeping (Use lazy sweeping for old pointer and data spaces)
- type: bool default: true
--never_compact (Never perform compaction on full GC - testing only)
type: bool default: false
--compact_code_space (Compact code space on full non-incremental collections)
type: bool default: true
+ --incremental_code_compaction (Compact code space on full incremental collections)
+ type: bool default: true
--cleanup_code_caches_at_gc (Flush inline caches prior to mark compact collection and flush code caches in maps during mark compact cycle.)
type: bool default: true
+ --use_marking_progress_bar (Use a progress bar to scan large objects in increments when incremental marking is active.)
+ type: bool default: true
+ --zap_code_space (Zap free memory in code space with 0xCC while sweeping.)
+ type: bool default: true
--random_seed (Default seed for initializing random generator (0, the default, means to use system random).)
type: int default: 0
+ --trace_weak_arrays (trace WeakFixedArray usage)
+ type: bool default: false
+ --track_prototype_users (keep track of which maps refer to a given prototype object)
+ type: bool default: false
--use_verbose_printer (allows verbose printing)
type: bool default: true
--allow_natives_syntax (allow natives syntax)
type: bool default: false
+ --trace_parse (trace parsing and preparsing)
+ type: bool default: false
--trace_sim (Trace simulator execution)
type: bool default: false
+ --debug_sim (Enable debugging the simulator)
+ type: bool default: false
--check_icache (Check icache flushes in ARM and MIPS simulator)
type: bool default: false
--stop_sim_at (Simulator stop after x number of instructions)
type: int default: 0
- --sim_stack_alignment (Stack alignment in bytes in simulator (4 or 8, 8 is default))
+ --sim_stack_alignment (Stack alingment in bytes in simulator (4 or 8, 8 is default))
type: int default: 8
- --trace_exception (print stack trace when throwing exceptions)
+ --sim_stack_size (Stack size of the ARM64 and MIPS64 simulator in kBytes (default is 2 MB))
+ type: int default: 2048
+ --log_regs_modified (When logging register values, only print modified registers.)
+ type: bool default: true
+ --log_colour (When logging, try to use coloured output.)
+ type: bool default: true
+ --ignore_asm_unimplemented_break (Don't break for ASM_UNIMPLEMENTED_BREAK macros.)
+ type: bool default: false
+ --trace_sim_messages (Trace simulator debug messages. Implied by --trace-sim.)
+ type: bool default: false
+ --stack_trace_on_illegal (print stack trace when an illegal exception is thrown)
type: bool default: false
- --preallocate_message_memory (preallocate some memory to build stack traces.)
+ --abort_on_uncaught_exception (abort program (dump core) when an uncaught exception is thrown)
type: bool default: false
--randomize_hashes (randomize hashes to avoid predictable hash collisions (with snapshots this option cannot override the baked-in seed))
type: bool default: true
--hash_seed (Fixed seed to use to hash property keys (0 means random)(with snapshots this option cannot override the baked-in seed))
type: int default: 0
- --preemption (activate a 100ms timer that switches between V8 threads)
+ --profile_deserialization (Print the time it takes to deserialize the snapshot.)
type: bool default: false
--regexp_optimization (generate optimized regexp code)
type: bool default: true
--testing_bool_flag (testing_bool_flag)
type: bool default: true
+ --testing_maybe_bool_flag (testing_maybe_bool_flag)
+ type: maybe_bool default: unset
--testing_int_flag (testing_int_flag)
type: int default: 13
--testing_float_flag (float-flag)
- type: float default: 2.500000
+ type: float default: 2.5
--testing_string_flag (string-flag)
type: string default: Hello, world!
--testing_prng_seed (Seed used for threading test randomness)
type: int default: 42
--testing_serialization_file (file in which to serialize heap)
type: string default: /tmp/serdes
+ --startup_blob (Write V8 startup blob file. (mksnapshot only))
+ type: string default: NULL
+ --profile_hydrogen_code_stub_compilation (Print the time it takes to lazily compile hydrogen code stubs.)
+ type: bool default: false
+ --predictable (enable predictable mode)
+ type: bool default: false
--help (Print usage message, including flags, on console)
type: bool default: true
--dump_counters (Dump counters on exit)
type: bool default: false
--debugger (Enable JavaScript debugger)
type: bool default: false
- --remote_debugger (Connect JavaScript debugger to the debugger agent in another process)
- type: bool default: false
- --debugger_agent (Enable debugger agent)
- type: bool default: false
- --debugger_port (Port to use for remote debugging)
- type: int default: 5858
--map_counters (Map counters to a file)
type: string default:
--js_arguments (Pass all remaining arguments to the script. Alias for "--".)
type: arguments default:
- --debug_compile_events (Enable debugger compile events)
- type: bool default: true
- --debug_script_collected_events (Enable debugger script collected events)
- type: bool default: true
--gdbjit (enable GDBJIT interface (disables compacting GC))
type: bool default: false
--gdbjit_full (enable GDBJIT interface for all code objects)
type: bool default: false
--gdbjit_dump_filter (dump only objects containing this substring)
type: string default:
- --force_marking_deque_overflows (force overflows of marking deque by reducing its size to 64 words)
+ --force_marking_deque_overflows (force overflows of marking deque by reducing it's size to 64 words)
type: bool default: false
--stress_compaction (stress the GC compactor to flush out bugs (implies --force_marking_deque_overflows))
type: bool default: false
type: bool default: false
--log_all (Log all events to the log file.)
type: bool default: false
- --log_runtime (Activate runtime system %Log call.)
- type: bool default: false
--log_api (Log API events to the log file.)
type: bool default: false
--log_code (Log code events to the log file without profiling.)
type: bool default: false
--prof (Log statistical profiling information (implies --log-code).)
type: bool default: false
- --prof_auto (Used with --prof, starts profiling automatically)
- type: bool default: true
- --prof_lazy (Used with --prof, only does sampling and logging when profiler is active (implies --noprof_auto).)
- type: bool default: false
--prof_browser_mode (Used with --prof, turns on browser-compatible mode for profiling.)
type: bool default: true
--log_regexp (Log regular expression execution.)
type: bool default: false
- --sliding_state_window (Update sliding state window counters.)
- type: bool default: false
--logfile (Specify the name of the log file.)
type: string default: v8.log
+ --logfile_per_isolate (Separate log files for each isolate.)
+ type: bool default: true
--ll_prof (Enable low-level linux profiler.)
type: bool default: false
+ --perf_basic_prof (Enable perf linux profiler (basic support).)
+ type: bool default: false
+ --perf_jit_prof (Enable perf linux profiler (experimental annotate support).)
+ type: bool default: false
+ --gc_fake_mmap (Specify the name of the file for fake gc mmap used in ll_prof)
+ type: string default: /tmp/__v8_gc__
+ --log_internal_timer_events (Time internal events.)
+ type: bool default: false
+ --log_timer_events (Time events including external callbacks.)
+ type: bool default: false
+ --log_instruction_stats (Log AArch64 instruction statistics.)
+ type: bool default: false
+ --log_instruction_file (AArch64 instruction statistics log file.)
+ type: string default: arm64_inst.csv
+ --log_instruction_period (AArch64 instruction statistics logging period.)
+ type: int default: 4194304
+ --redirect_code_traces (output deopt information and disassembly into file code-<pid>-<isolate id>.asm)
+ type: bool default: false
+ --redirect_code_traces_to (output deopt information and disassembly into the given file)
+ type: string default: NULL
+ --hydrogen_track_positions (track source code positions when building IR)
+ type: bool default: false
+ --trace_elements_transitions (trace elements transitions)
+ type: bool default: false
+ --trace_creation_allocation_sites (trace the creation of allocation sites)
+ type: bool default: false
+ --print_code_stubs (print code stubs)
+ type: bool default: false
+ --test_secondary_stub_cache (test secondary stub cache by disabling the primary one)
+ type: bool default: false
+ --test_primary_stub_cache (test primary stub cache by disabling the secondary one)
+ type: bool default: false
+ --print_code (print generated code)
+ type: bool default: false
+ --print_opt_code (print optimized code)
+ type: bool default: false
+ --print_unopt_code (print unoptimized code before printing optimized code based on it)
+ type: bool default: false
+ --print_code_verbose (print more information for code)
+ type: bool default: false
+ --print_builtin_code (print generated code for builtins)
+ type: bool default: false
+ --sodium (print generated code output suitable for use with the Sodium code viewer)
+ type: bool default: false
+ --print_all_code (enable all flags related to printing code)
+ type: bool default: false
.SH RESOURCES AND DOCUMENTATION
projects / platform / upstream / nodejs.git / commitdiff