v8/src/flag-definitions.h

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// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// 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:
// We want to declare the names of the variables for the header file. Normally
// this will just be an extern declaration, but for a readonly flag we let the
// compiler make better optimizations by giving it the value.
#if defined(FLAG_MODE_DECLARE)
#define FLAG_FULL(ftype, ctype, nam, def, cmt) \
extern ctype FLAG_##nam;
#define FLAG_READONLY(ftype, ctype, nam, def, cmt) \
static ctype const FLAG_##nam = def;
// We want to supply the actual storage and value for the flag variable in the
// .cc file. We only do this for writable flags.
#elif defined(FLAG_MODE_DEFINE)
#define FLAG_FULL(ftype, ctype, nam, def, cmt) \
ctype FLAG_##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 ctype const FLAGDEFAULT_##nam = def;
// We want to write entries into our meta data table, for internal parsing and
// printing / etc in the flag parser code. We only do this for writable flags.
#elif defined(FLAG_MODE_META)
#define FLAG_FULL(ftype, ctype, nam, def, cmt) \
{ Flag::TYPE_##ftype, #nam, &FLAG_##nam, &FLAGDEFAULT_##nam, cmt, false },
#define FLAG_ALIAS(ftype, ctype, alias, nam) \
{ Flag::TYPE_##ftype, #alias, &FLAG_##nam, &FLAGDEFAULT_##nam, \
"alias for --"#nam, false },
// We produce the code to set flags when it is implied by another flag.
#elif defined(FLAG_MODE_DEFINE_IMPLICATIONS)
#define DEFINE_implication(whenflag, thenflag) \
if (FLAG_##whenflag) FLAG_##thenflag = true;
#define DEFINE_neg_implication(whenflag, thenflag) \
if (FLAG_##whenflag) FLAG_##thenflag = false;
#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_implication
#define DEFINE_implication(whenflag, thenflag)
#endif
#ifndef DEFINE_neg_implication
#define DEFINE_neg_implication(whenflag, thenflag)
#endif
#define COMMA ,
#ifdef FLAG_MODE_DECLARE
// Structure used to hold a collection of arguments to the JavaScript code.
struct JSArguments {
public:
inline const char*& operator[] (int idx) const {
return argv[idx];
}
static JSArguments Create(int argc, const char** argv) {
JSArguments args;
args.argc = argc;
args.argv = argv;
return args;
}
int argc;
const char** argv;
};
struct MaybeBoolFlag {
static MaybeBoolFlag Create(bool has_value, bool value) {
MaybeBoolFlag flag;
flag.has_value = has_value;
flag.value = value;
return flag;
}
bool has_value;
bool value;
};
#endif
#if (defined CAN_USE_VFP3_INSTRUCTIONS) || !(defined ARM_TEST)
# define ENABLE_VFP3_DEFAULT true
#else
# define ENABLE_VFP3_DEFAULT false
#endif
#if (defined CAN_USE_ARMV7_INSTRUCTIONS) || !(defined ARM_TEST)
# define ENABLE_ARMV7_DEFAULT true
#else
# define ENABLE_ARMV7_DEFAULT false
#endif
#if (defined CAN_USE_VFP32DREGS) || !(defined ARM_TEST)
# define ENABLE_32DREGS_DEFAULT true
#else
# define ENABLE_32DREGS_DEFAULT false
#endif
#define DEFINE_bool(nam, def, cmt) FLAG(BOOL, bool, nam, def, cmt)
#define DEFINE_maybe_bool(nam, cmt) FLAG(MAYBE_BOOL, MaybeBoolFlag, nam, \
{ false COMMA false }, cmt)
#define DEFINE_int(nam, def, cmt) FLAG(INT, int, nam, def, cmt)
#define DEFINE_float(nam, def, cmt) FLAG(FLOAT, double, nam, def, cmt)
#define DEFINE_string(nam, def, cmt) FLAG(STRING, const char*, nam, def, cmt)
#define DEFINE_args(nam, cmt) FLAG(ARGS, JSArguments, nam, \
{ 0 COMMA NULL }, 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_string(alias, nam) \
FLAG_ALIAS(STRING, const char*, alias, nam)
#define DEFINE_ALIAS_args(alias, nam) FLAG_ALIAS(ARGS, JSArguments, alias, nam)
//
// Flags in all modes.
//
#define FLAG FLAG_FULL
// Flags for language modes and experimental language features.
DEFINE_bool(use_strict, false, "enforce strict mode")
DEFINE_bool(es5_readonly, true,
"activate correct semantics for inheriting readonliness")
DEFINE_bool(es52_globals, true,
"activate new semantics for global var declarations")
DEFINE_bool(harmony_typeof, false, "enable harmony semantics for typeof")
DEFINE_bool(harmony_scoping, false, "enable harmony block scoping")
DEFINE_bool(harmony_modules, false,
"enable harmony modules (implies block scoping)")
DEFINE_bool(harmony_symbols, false,
"enable harmony symbols (a.k.a. private names)")
DEFINE_bool(harmony_promises, false, "enable harmony promises")
DEFINE_bool(harmony_proxies, false, "enable harmony proxies")
DEFINE_bool(harmony_collections, false,
"enable harmony collections (sets, maps, and weak maps)")
DEFINE_bool(harmony_observation, false,
"enable harmony object observation (implies harmony collections")
DEFINE_bool(harmony_generators, false, "enable harmony generators")
DEFINE_bool(harmony_iteration, false, "enable harmony iteration (for-of)")
DEFINE_bool(harmony_numeric_literals, false,
"enable harmony numeric literals (0o77, 0b11)")
DEFINE_bool(harmony_strings, false, "enable harmony string")
DEFINE_bool(harmony_arrays, false, "enable harmony arrays")
DEFINE_bool(harmony_maths, false, "enable harmony math functions")
DEFINE_bool(harmony, false, "enable all harmony features (except typeof)")
DEFINE_implication(harmony, harmony_scoping)
DEFINE_implication(harmony, harmony_modules)
DEFINE_implication(harmony, harmony_symbols)
DEFINE_implication(harmony, harmony_promises)
DEFINE_implication(harmony, harmony_proxies)
DEFINE_implication(harmony, harmony_collections)
DEFINE_implication(harmony, harmony_observation)
DEFINE_implication(harmony, harmony_generators)
DEFINE_implication(harmony, harmony_iteration)
DEFINE_implication(harmony, harmony_numeric_literals)
DEFINE_implication(harmony, harmony_strings)
DEFINE_implication(harmony, harmony_arrays)
DEFINE_implication(harmony, harmony_maths)
DEFINE_implication(harmony_promises, harmony_collections)
DEFINE_implication(harmony_modules, harmony_scoping)
DEFINE_implication(harmony_observation, harmony_collections)
// Flags for experimental implementation features.
DEFINE_bool(packed_arrays, true, "optimizes arrays that have no holes")
DEFINE_bool(smi_only_arrays, true, "tracks arrays with only smi values")
DEFINE_bool(compiled_keyed_dictionary_loads, true,
"use optimizing compiler to generate keyed dictionary load stubs")
DEFINE_bool(clever_optimizations, true,
"Optimize object size, Array shift, DOM strings and string +")
DEFINE_bool(pretenuring, true, "allocate objects in old space")
// TODO(hpayer): We will remove this flag as soon as we have pretenuring
// support for specific allocation sites.
DEFINE_bool(pretenuring_call_new, false, "pretenure call new")
DEFINE_bool(allocation_site_pretenuring, true,
"pretenure with allocation sites")
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_fields, true, "track fields with only smi values")
DEFINE_bool(track_double_fields, true, "track fields with double values")
DEFINE_bool(track_heap_object_fields, true, "track fields with heap values")
DEFINE_bool(track_computed_fields, true, "track computed boilerplate fields")
DEFINE_implication(track_double_fields, track_fields)
DEFINE_implication(track_heap_object_fields, track_fields)
DEFINE_implication(track_computed_fields, track_fields)
DEFINE_bool(smi_binop, true, "support smi representation in binary operations")
// Flags for optimization types.
DEFINE_bool(optimize_for_size, false,
"Enables optimizations which favor memory size over execution "
"speed.")
// Flags for data representation optimizations
DEFINE_bool(unbox_double_arrays, true, "automatically unbox arrays of doubles")
DEFINE_bool(string_slices, true, "use string slices")
// Flags for Crankshaft.
DEFINE_bool(crankshaft, true, "use crankshaft")
DEFINE_string(hydrogen_filter, "*", "optimization filter")
DEFINE_bool(use_range, true, "use hydrogen range analysis")
DEFINE_bool(use_gvn, true, "use hydrogen global value numbering")
DEFINE_int(gvn_iterations, 3, "maximum number of GVN fix-point iterations")
DEFINE_bool(use_canonicalizing, true, "use hydrogen instruction canonicalizing")
DEFINE_bool(use_inlining, true, "use function inlining")
DEFINE_bool(use_escape_analysis, true, "use hydrogen escape analysis")
DEFINE_bool(use_allocation_folding, true, "use allocation folding")
DEFINE_bool(use_local_allocation_folding, false, "only fold in basic blocks")
DEFINE_bool(use_write_barrier_elimination, true,
"eliminate write barriers targeting allocations in optimized code")
DEFINE_int(max_inlining_levels, 5, "maximum number of inlining levels")
DEFINE_int(max_inlined_source_size, 600,
"maximum source size in bytes considered for a single inlining")
DEFINE_int(max_inlined_nodes, 196,
"maximum number of AST nodes considered for a single inlining")
DEFINE_int(max_inlined_nodes_cumulative, 400,
"maximum cumulative number of AST nodes considered for inlining")
DEFINE_bool(loop_invariant_code_motion, true, "loop invariant code motion")
DEFINE_bool(fast_math, true, "faster (but maybe less accurate) math functions")
DEFINE_bool(collect_megamorphic_maps_from_stub_cache, true,
"crankshaft harvests type feedback from stub cache")
DEFINE_bool(hydrogen_stats, false, "print statistics for hydrogen")
DEFINE_bool(trace_check_elimination, false, "trace check elimination phase")
DEFINE_bool(trace_hydrogen, false, "trace generated hydrogen to file")
DEFINE_string(trace_hydrogen_filter, "*", "hydrogen tracing filter")
DEFINE_bool(trace_hydrogen_stubs, false, "trace generated hydrogen for stubs")
DEFINE_string(trace_hydrogen_file, NULL, "trace hydrogen to given file name")
DEFINE_string(trace_phase, "HLZ", "trace generated IR for specified phases")
DEFINE_bool(trace_inlining, false, "trace inlining decisions")
DEFINE_bool(trace_load_elimination, false, "trace load elimination")
DEFINE_bool(trace_alloc, false, "trace register allocator")
DEFINE_bool(trace_all_uses, false, "trace all use positions")
DEFINE_bool(trace_range, false, "trace range analysis")
DEFINE_bool(trace_gvn, false, "trace global value numbering")
DEFINE_bool(trace_representation, false, "trace representation types")
DEFINE_bool(trace_escape_analysis, false, "trace hydrogen escape analysis")
DEFINE_bool(trace_allocation_folding, false, "trace allocation folding")
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(stress_pointer_maps, false, "pointer map for every instruction")
DEFINE_bool(stress_environments, false, "environment for every instruction")
DEFINE_int(deopt_every_n_times, 0,
"deoptimize every n times a deopt point is passed")
DEFINE_int(deopt_every_n_garbage_collections, 0,
"deoptimize every n garbage collections")
DEFINE_bool(print_deopt_stress, false, "print number of possible deopt points")
DEFINE_bool(trap_on_deopt, false, "put a break point before deoptimizing")
DEFINE_bool(trap_on_stub_deopt, false,
"put a break point before deoptimizing a stub")
DEFINE_bool(deoptimize_uncommon_cases, true, "deoptimize uncommon cases")
DEFINE_bool(polymorphic_inlining, true, "polymorphic inlining")
DEFINE_bool(use_osr, true, "use on-stack replacement")
DEFINE_bool(array_bounds_checks_elimination, true,
"perform array bounds checks elimination")
DEFINE_bool(array_bounds_checks_hoisting, false,
"perform array bounds checks hoisting")
DEFINE_bool(array_index_dehoisting, true,
"perform array index dehoisting")
DEFINE_bool(analyze_environment_liveness, true,
"analyze liveness of environment slots and zap dead values")
DEFINE_bool(load_elimination, true, "use load elimination")
DEFINE_bool(check_elimination, true, "use check elimination")
DEFINE_bool(dead_code_elimination, true, "use dead code elimination")
DEFINE_bool(fold_constants, true, "use constant folding")
DEFINE_bool(trace_dead_code_elimination, false, "trace dead code elimination")
DEFINE_bool(unreachable_code_elimination, true, "eliminate unreachable code")
DEFINE_bool(trace_osr, false, "trace on-stack replacement")
DEFINE_int(stress_runs, 0, "number of stress runs")
DEFINE_bool(optimize_closures, true, "optimize closures")
DEFINE_bool(lookup_sample_by_shared, true,
"when picking a function to optimize, watch for shared function "
"info, not JSFunction itself")
DEFINE_bool(cache_optimized_code, true,
"cache optimized code for closures")
DEFINE_bool(flush_optimized_code_cache, true,
"flushes the cache of optimized code for closures on every GC")
DEFINE_bool(inline_construct, true, "inline constructor calls")
DEFINE_bool(inline_arguments, true, "inline functions with arguments object")
DEFINE_bool(inline_accessors, true, "inline JavaScript accessors")
DEFINE_int(escape_analysis_iterations, 2,
"maximum number of escape analysis fix-point iterations")
DEFINE_bool(optimize_for_in, true,
"optimize functions containing for-in loops")
DEFINE_bool(opt_safe_uint32_operations, true,
"allow uint32 values on optimize frames if they are used only in "
"safe operations")
DEFINE_bool(concurrent_recompilation, true,
"optimizing hot functions asynchronously on a separate thread")
DEFINE_bool(trace_concurrent_recompilation, false,
"track concurrent recompilation")
DEFINE_int(concurrent_recompilation_queue_length, 8,
"the length of the concurrent compilation queue")
DEFINE_int(concurrent_recompilation_delay, 0,
"artificial compilation delay in ms")
DEFINE_bool(block_concurrent_recompilation, false,
"block queued jobs until released")
DEFINE_bool(concurrent_osr, false,
"concurrent on-stack replacement")
DEFINE_implication(concurrent_osr, concurrent_recompilation)
DEFINE_bool(omit_map_checks_for_leaf_maps, true,
"do not emit check maps for constant values that have a leaf map, "
"deoptimize the optimized code if the layout of the maps changes.")
// Profiler flags.
DEFINE_int(frame_count, 1, "number of stack frames inspected by the profiler")
// 0x1800 fits in the immediate field of an ARM instruction.
DEFINE_int(interrupt_budget, 0x1800,
"execution budget before interrupt is triggered")
DEFINE_int(type_info_threshold, 25,
"percentage of ICs that must have type info to allow optimization")
DEFINE_int(self_opt_count, 130, "call count before self-optimization")
DEFINE_bool(trace_opt_verbose, false, "extra verbose compilation tracing")
DEFINE_implication(trace_opt_verbose, trace_opt)
// assembler-ia32.cc / assembler-arm.cc / assembler-x64.cc
DEFINE_bool(debug_code, false,
"generate extra code (assertions) for debugging")
DEFINE_bool(code_comments, false, "emit comments in code disassembly")
DEFINE_bool(enable_sse2, true,
"enable use of SSE2 instructions if available")
DEFINE_bool(enable_sse3, true,
"enable use of SSE3 instructions if available")
DEFINE_bool(enable_sse4_1, true,
"enable use of SSE4.1 instructions if available")
DEFINE_bool(enable_cmov, true,
"enable use of CMOV instruction if available")
DEFINE_bool(enable_sahf, true,
"enable use of SAHF instruction if available (X64 only)")
DEFINE_bool(enable_vfp3, ENABLE_VFP3_DEFAULT,
"enable use of VFP3 instructions if available")
DEFINE_bool(enable_armv7, ENABLE_ARMV7_DEFAULT,
"enable use of ARMv7 instructions if available (ARM only)")
DEFINE_bool(enable_neon, true,
"enable use of NEON instructions if available (ARM only)")
DEFINE_bool(enable_sudiv, true,
"enable use of SDIV and UDIV instructions if available (ARM only)")
DEFINE_bool(enable_movw_movt, false,
"enable loading 32-bit constant by means of movw/movt "
"instruction pairs (ARM only)")
DEFINE_bool(enable_unaligned_accesses, true,
"enable unaligned accesses for ARMv7 (ARM only)")
DEFINE_bool(enable_32dregs, ENABLE_32DREGS_DEFAULT,
"enable use of d16-d31 registers on ARM - this requires VFP3")
DEFINE_bool(enable_vldr_imm, false,
"enable use of constant pools for double immediate (ARM only)")
DEFINE_bool(force_long_branches, false,
"force all emitted branches to be in long mode (MIPS only)")
// bootstrapper.cc
DEFINE_string(expose_natives_as, NULL, "expose natives in global object")
DEFINE_string(expose_debug_as, NULL, "expose debug in global object")
DEFINE_bool(expose_free_buffer, false, "expose freeBuffer extension")
DEFINE_bool(expose_gc, false, "expose gc extension")
DEFINE_string(expose_gc_as, NULL,
"expose gc extension under the specified name")
DEFINE_implication(expose_gc_as, expose_gc)
DEFINE_bool(expose_externalize_string, false,
"expose externalize string extension")
DEFINE_bool(expose_trigger_failure, false, "expose trigger-failure extension")
DEFINE_int(stack_trace_limit, 10, "number of stack frames to capture")
DEFINE_bool(builtins_in_stack_traces, false,
"show built-in functions in stack traces")
DEFINE_bool(disable_native_files, false, "disable builtin natives files")
// builtins-ia32.cc
DEFINE_bool(inline_new, true, "use fast inline allocation")
// codegen-ia32.cc / codegen-arm.cc
DEFINE_bool(trace_codegen, false,
"print name of functions for which code is generated")
DEFINE_bool(trace, false, "trace function calls")
DEFINE_bool(mask_constants_with_cookie, true,
"use random jit cookie to mask large constants")
// codegen.cc
DEFINE_bool(lazy, true, "use lazy compilation")
DEFINE_bool(trace_opt, false, "trace lazy optimization")
DEFINE_bool(trace_opt_stats, false, "trace lazy optimization statistics")
DEFINE_bool(opt, true, "use adaptive optimizations")
DEFINE_bool(always_opt, false, "always try to optimize functions")
DEFINE_bool(always_osr, false, "always try to OSR functions")
DEFINE_bool(prepare_always_opt, false, "prepare for turning on always opt")
DEFINE_bool(trace_deopt, false, "trace optimize function deoptimization")
DEFINE_bool(trace_stub_failures, false,
"trace deoptimization of generated code stubs")
// compiler.cc
DEFINE_int(min_preparse_length, 1024,
Initial infrastructure for fast compilation of top-level code. The fast code generator is optimized for compilation time and code size. Currently it is only implemented on IA32. It is potentially triggered for any code in the global scope (including code eval'd in the global scope). It performs a syntactic check and chooses to compile in fast mode if the AST contains only supported constructs and matches some other constraints. Initially supported constructs are * ExpressionStatement, * ReturnStatement, * VariableProxy (variable references) to parameters and stack-allocated locals, * Assignment with lhs a parameter or stack-allocated local, and * Literal This allows compilation of literals at the top level and not much else. All intermediate values are allocated to temporaries and the stack is used for all temporaries. The extra memory traffic is a known issue. The code generated for 'true' is: 0 push ebp 1 mov ebp,esp 3 push esi 4 push edi 5 push 0xf5cca135 ;; object: 0xf5cca135 <undefined> 10 cmp esp,[0x8277efc] 16 jnc 27 (0xf5cbbb1b) 22 call 0xf5cac960 ;; code: STUB, StackCheck, minor: 0 27 push 0xf5cca161 ;; object: 0xf5cca161 <true> 32 mov eax,[esp] 35 mov [ebp+0xf4],eax 38 pop eax 39 mov eax,[ebp+0xf4] 42 mov esp,ebp ;; js return 44 pop ebp 45 ret 0x4 48 mov eax,0xf5cca135 ;; object: 0xf5cca135 <undefined> 53 mov esp,ebp ;; js return 55 pop ebp 56 ret 0x4 Review URL: http://codereview.chromium.org/273050 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3067 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2009-10-14 19:30:50 +00:00
"minimum length for automatic enable preparsing")
DEFINE_bool(always_full_compiler, false,
"try to use the dedicated run-once backend for all code")
DEFINE_int(max_opt_count, 10,
"maximum number of optimization attempts before giving up.")
// compilation-cache.cc
DEFINE_bool(compilation_cache, true, "enable compilation cache")
DEFINE_bool(cache_prototype_transitions, true, "cache prototype transitions")
Support higher CPU profiler sampling rate on posix systems New flag is added that allows to specify CPU profiler sampling rate in microseconds as command line argument. It was tested to work fine with 100us interval(currently it is 1ms). Default values are kept the same as in the current implementation. The new implementation is enabled only on POSIX platforms which use signals to collect samples. Other platforms that pause thread being sampled are to follow. SIGPROF signals are now sent on the profiler event processor thread to make sure that the processing thread does fall far behind the sampling. The patch is based on the previous one that was rolled out in r13851. The main difference is that the circular queue is not modified for now. On Linux sampling for CPU profiler is initiated on the profiler event processor thread, other platforms to follow. CPU profiler continues to use SamplingCircularQueue, we will probably replace it with a single sample buffer when Mac and Win ports support profiling on the event processing thread. When --prof option is specified profiling is initiated either on the profiler event processor thread if CPU profiler is on or on the SignalSender thread as it used to be if no CPU profiles are being collected. ProfilerEventsProcessor::ProcessEventsAndDoSample now waits in a tight loop, processing collected samples until sampling interval expires. To save CPU resources I'm planning to change that to use nanosleep as only one sample is expected in the queue at any point. BUG=v8:2814 R=bmeurer@chromium.org Review URL: https://codereview.chromium.org/21101002 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16310 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2013-08-26 07:17:12 +00:00
// cpu-profiler.cc
DEFINE_int(cpu_profiler_sampling_interval, 1000,
Support higher CPU profiler sampling rate on posix systems New flag is added that allows to specify CPU profiler sampling rate in microseconds as command line argument. It was tested to work fine with 100us interval(currently it is 1ms). Default values are kept the same as in the current implementation. The new implementation is enabled only on POSIX platforms which use signals to collect samples. Other platforms that pause thread being sampled are to follow. SIGPROF signals are now sent on the profiler event processor thread to make sure that the processing thread does fall far behind the sampling. The patch is based on the previous one that was rolled out in r13851. The main difference is that the circular queue is not modified for now. On Linux sampling for CPU profiler is initiated on the profiler event processor thread, other platforms to follow. CPU profiler continues to use SamplingCircularQueue, we will probably replace it with a single sample buffer when Mac and Win ports support profiling on the event processing thread. When --prof option is specified profiling is initiated either on the profiler event processor thread if CPU profiler is on or on the SignalSender thread as it used to be if no CPU profiles are being collected. ProfilerEventsProcessor::ProcessEventsAndDoSample now waits in a tight loop, processing collected samples until sampling interval expires. To save CPU resources I'm planning to change that to use nanosleep as only one sample is expected in the queue at any point. BUG=v8:2814 R=bmeurer@chromium.org Review URL: https://codereview.chromium.org/21101002 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16310 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2013-08-26 07:17:12 +00:00
"CPU profiler sampling interval in microseconds")
// debug.cc
DEFINE_bool(trace_debug_json, false, "trace debugging JSON request/response")
DEFINE_bool(trace_js_array_abuse, false,
"trace out-of-bounds accesses to JS arrays")
DEFINE_bool(trace_external_array_abuse, false,
"trace out-of-bounds-accesses to external arrays")
DEFINE_bool(trace_array_abuse, false,
"trace out-of-bounds accesses to all arrays")
DEFINE_implication(trace_array_abuse, trace_js_array_abuse)
DEFINE_implication(trace_array_abuse, trace_external_array_abuse)
DEFINE_bool(debugger_auto_break, true,
"automatically set the debug break flag when debugger commands are "
"in the queue")
DEFINE_bool(enable_liveedit, true, "enable liveedit experimental feature")
DEFINE_bool(hard_abort, true, "abort by crashing")
// execution.cc
// Slightly less than 1MB on 64-bit, since Windows' default stack size for
// the main execution thread is 1MB for both 32 and 64-bit.
DEFINE_int(stack_size, kPointerSize * 123,
"default size of stack region v8 is allowed to use (in kBytes)")
// frames.cc
DEFINE_int(max_stack_trace_source_length, 300,
"maximum length of function source code printed in a stack trace.")
// full-codegen.cc
DEFINE_bool(always_inline_smi_code, false,
"always inline smi code in non-opt code")
// heap.cc
DEFINE_int(max_new_space_size, 0, "max size of the new generation (in kBytes)")
DEFINE_int(max_old_space_size, 0, "max size of the old generation (in Mbytes)")
DEFINE_int(max_executable_size, 0, "max size of executable memory (in Mbytes)")
DEFINE_bool(gc_global, false, "always perform global GCs")
DEFINE_int(gc_interval, -1, "garbage collect after <n> allocations")
DEFINE_bool(trace_gc, false,
"print one trace line following each garbage collection")
DEFINE_bool(trace_gc_nvp, false,
"print one detailed trace line in name=value format "
"after each garbage collection")
DEFINE_bool(trace_gc_ignore_scavenger, false,
"do not print trace line after scavenger collection")
DEFINE_bool(print_cumulative_gc_stat, false,
"print cumulative GC statistics in name=value format on exit")
DEFINE_bool(print_max_heap_committed, false,
"print statistics of the maximum memory committed for the heap "
"in name=value format on exit")
DEFINE_bool(trace_gc_verbose, false,
"print more details following each garbage collection")
DEFINE_bool(trace_fragmentation, false,
"report fragmentation for old pointer and data pages")
DEFINE_bool(trace_external_memory, false,
"print amount of external allocated memory after each time "
"it is adjusted.")
DEFINE_bool(collect_maps, true,
"garbage collect maps from which no objects can be reached")
DEFINE_bool(weak_embedded_maps_in_optimized_code, true,
"make maps embedded in optimized code weak")
DEFINE_bool(weak_embedded_objects_in_optimized_code, true,
"make objects embedded in optimized code weak")
DEFINE_bool(flush_code, true,
"flush code that we expect not to use again (during full gc)")
DEFINE_bool(flush_code_incrementally, true,
"flush code that we expect not to use again (incrementally)")
DEFINE_bool(trace_code_flushing, false, "trace code flushing progress")
DEFINE_bool(age_code, true,
"track un-executed functions to age code and flush only "
"old code (required for code flushing)")
DEFINE_bool(incremental_marking, true, "use incremental marking")
DEFINE_bool(incremental_marking_steps, true, "do incremental marking steps")
DEFINE_bool(trace_incremental_marking, false,
"trace progress of the incremental marking")
DEFINE_bool(track_gc_object_stats, false,
"track object counts and memory usage")
DEFINE_bool(parallel_sweeping, true, "enable parallel sweeping")
DEFINE_bool(concurrent_sweeping, false, "enable concurrent sweeping")
DEFINE_int(sweeper_threads, 0,
"number of parallel and concurrent sweeping threads")
DEFINE_bool(job_based_sweeping, false, "enable job based sweeping")
#ifdef VERIFY_HEAP
DEFINE_bool(verify_heap, false, "verify heap pointers before and after GC")
#endif
// heap-snapshot-generator.cc
DEFINE_bool(heap_profiler_trace_objects, false,
"Dump heap object allocations/movements/size_updates")
// v8.cc
DEFINE_bool(use_idle_notification, true,
"Use idle notification to reduce memory footprint.")
// ic.cc
DEFINE_bool(use_ic, true, "use inline caching")
// macro-assembler-ia32.cc
DEFINE_bool(native_code_counters, false,
"generate extra code for manipulating stats counters")
// mark-compact.cc
DEFINE_bool(always_compact, false, "Perform compaction on every full GC")
DEFINE_bool(lazy_sweeping, true,
"Use lazy sweeping for old pointer and data spaces")
DEFINE_bool(never_compact, false,
"Never perform compaction on full GC - testing only")
DEFINE_bool(compact_code_space, true,
"Compact code space on full non-incremental collections")
DEFINE_bool(incremental_code_compaction, true,
"Compact code space on full incremental collections")
DEFINE_bool(cleanup_code_caches_at_gc, true,
"Flush inline caches prior to mark compact collection and "
"flush code caches in maps during mark compact cycle.")
DEFINE_bool(use_marking_progress_bar, true,
"Use a progress bar to scan large objects in increments when "
"incremental marking is active.")
DEFINE_int(random_seed, 0,
"Default seed for initializing random generator "
"(0, the default, means to use system random).")
// objects.cc
DEFINE_bool(use_verbose_printer, true, "allows verbose printing")
// parser.cc
DEFINE_bool(allow_natives_syntax, false, "allow natives syntax")
DEFINE_bool(trace_parse, false, "trace parsing and preparsing")
// simulator-arm.cc, simulator-a64.cc and simulator-mips.cc
DEFINE_bool(trace_sim, false, "Trace simulator execution")
DEFINE_bool(check_icache, false,
"Check icache flushes in ARM and MIPS simulator")
DEFINE_int(stop_sim_at, 0, "Simulator stop after x number of instructions")
#ifdef V8_TARGET_ARCH_A64
DEFINE_int(sim_stack_alignment, 16,
"Stack alignment in bytes in simulator. This must be a power of two "
"and it must be at least 16. 16 is default.")
#else
DEFINE_int(sim_stack_alignment, 8,
"Stack alingment in bytes in simulator (4 or 8, 8 is default)")
#endif
DEFINE_int(sim_stack_size, 2 * MB / KB,
"Stack size of the A64 simulator in kBytes (default is 2 MB)")
DEFINE_bool(log_regs_modified, true,
"When logging register values, only print modified registers.")
DEFINE_bool(log_colour, true,
"When logging, try to use coloured output.")
DEFINE_bool(ignore_asm_unimplemented_break, false,
"Don't break for ASM_UNIMPLEMENTED_BREAK macros.")
DEFINE_bool(trace_sim_messages, false,
"Trace simulator debug messages. Implied by --trace-sim.")
// isolate.cc
DEFINE_bool(stack_trace_on_illegal, false,
"print stack trace when an illegal exception is thrown")
DEFINE_bool(abort_on_uncaught_exception, false,
"abort program (dump core) when an uncaught exception is thrown")
DEFINE_bool(randomize_hashes, true,
"randomize hashes to avoid predictable hash collisions "
"(with snapshots this option cannot override the baked-in seed)")
DEFINE_int(hash_seed, 0,
"Fixed seed to use to hash property keys (0 means random)"
"(with snapshots this option cannot override the baked-in seed)")
// snapshot-common.cc
DEFINE_bool(profile_deserialization, false,
"Print the time it takes to deserialize the snapshot.")
// Regexp
DEFINE_bool(regexp_optimization, true, "generate optimized regexp code")
// Testing flags test/cctest/test-{flags,api,serialization}.cc
DEFINE_bool(testing_bool_flag, true, "testing_bool_flag")
DEFINE_maybe_bool(testing_maybe_bool_flag, "testing_maybe_bool_flag")
DEFINE_int(testing_int_flag, 13, "testing_int_flag")
DEFINE_float(testing_float_flag, 2.5, "float-flag")
DEFINE_string(testing_string_flag, "Hello, world!", "string-flag")
DEFINE_int(testing_prng_seed, 42, "Seed used for threading test randomness")
#ifdef _WIN32
DEFINE_string(testing_serialization_file, "C:\\Windows\\Temp\\serdes",
"file in which to testing_serialize heap")
#else
DEFINE_string(testing_serialization_file, "/tmp/serdes",
"file in which to serialize heap")
#endif
// mksnapshot.cc
DEFINE_string(extra_code, NULL, "A filename with extra code to be included in"
" the snapshot (mksnapshot only)")
// code-stubs-hydrogen.cc
DEFINE_bool(profile_hydrogen_code_stub_compilation, false,
"Print the time it takes to lazily compile hydrogen code stubs.")
DEFINE_bool(predictable, false, "enable predictable mode")
DEFINE_neg_implication(predictable, randomize_hashes)
DEFINE_neg_implication(predictable, concurrent_recompilation)
DEFINE_neg_implication(predictable, concurrent_osr)
DEFINE_neg_implication(predictable, concurrent_sweeping)
DEFINE_neg_implication(predictable, parallel_sweeping)
//
// Dev shell flags
//
DEFINE_bool(help, false, "Print usage message, including flags, on console")
DEFINE_bool(dump_counters, false, "Dump counters on exit")
#ifdef ENABLE_DEBUGGER_SUPPORT
DEFINE_bool(debugger, false, "Enable JavaScript debugger")
DEFINE_bool(remote_debugger, false, "Connect JavaScript debugger to the "
"debugger agent in another process")
DEFINE_bool(debugger_agent, false, "Enable debugger agent")
DEFINE_int(debugger_port, 5858, "Port to use for remote debugging")
#endif // ENABLE_DEBUGGER_SUPPORT
DEFINE_string(map_counters, "", "Map counters to a file")
DEFINE_args(js_arguments,
"Pass all remaining arguments to the script. Alias for \"--\".")
Misc debugger enhancements and bug fixes. 1. Added gdb style debugger commands (and their shortcuts) for d8. These include: - s[tep] : step into the current statement. - s[tep]i[n]: step into the current statement with the minimum step. - n[ext] : step to the next statement. - fin[ish] : step out of the current function. - cond : setting conditions on breakpoints. - d[elete] : deletes breakpoints. - en[able]|dis[able]: enables/disables breakpoints including exception breakpoints. - ignore : ignores a breakpoint for a specified period. - inf[o] ar[gs] : info on arguments of the current function. - inf[o] lo[cals] : info on local vars of the current function. - inf[o] br[eakpoints] : info on breakpoints. - l[ist] : similar to source, but allows the user to continually dump subsequent lines of source code either in the forward or backward direction. - quit / exit / disconnect : terminates the remote debugger session. NOTE: Active breakpoints will automatically be disabled when the remote debugger detaches. This allows v8 to continue to run without worrying about a loss of a debugger session. 2. Added support for breaking the debugger by simply typing ENTER. The break command is now optional. 3. Once the debugger is broken, the user can now just type ENTER to repeat the last command. This is useful to functionality that needs to be invoked repeatedly e.g. step, list. 4. Added more verbose descriptions in d8's help. 5. Fixed a line and column number offset bug in the listing of breakpoint line and column numbers. 6. Added a gc command to allow GCs to be requested from the debugger interface. The plumbing for requesting different types of GCs is there, but the underlying implementation currently only triggers a full mark-compact GC. The command also returns the before and after sizes of the heap. 7. Added trace json, and flags commands that are not published in help. trace json is used for tracing the debugger packets send from and received by d8. flags is for setting v8 flags. These are useful for people debugging v8 itself, but not necessarily users of v8. 8. Added the ability to enable and disable break on all / uncaught exceptions in to d8. 9. Added a fix to prevent the Debugger Agent from being re-instantiated if one already exists. 10. Added the ability to filter results of the script command by matching text or numbers on the results. 11. Added v8 flags to enable/disable the sending of debugger BeforeCompile, AfterCompile, and ScriptCollected events. 12. Fixed some undefined value bugs that resulted in v8 or the debugger failing. 13. Added a few minor WEBOS__ customizations (analogous to ANDROID customizations). Patch by Mark Lam from Hewlett-Packard Development Company, LP Review URL: http://codereview.chromium.org/5980006 Review URL: http://codereview.chromium.org/6086010 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6200 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2011-01-06 13:14:32 +00:00
#if defined(WEBOS__)
DEFINE_bool(debug_compile_events, false, "Enable debugger compile events")
DEFINE_bool(debug_script_collected_events, false,
"Enable debugger script collected events")
#else
DEFINE_bool(debug_compile_events, true, "Enable debugger compile events")
DEFINE_bool(debug_script_collected_events, true,
"Enable debugger script collected events")
#endif
//
// GDB JIT integration flags.
//
DEFINE_bool(gdbjit, false, "enable GDBJIT interface (disables compacting GC)")
DEFINE_bool(gdbjit_full, false, "enable GDBJIT interface for all code objects")
DEFINE_bool(gdbjit_dump, false, "dump elf objects with debug info to disk")
DEFINE_string(gdbjit_dump_filter, "",
"dump only objects containing this substring")
// mark-compact.cc
DEFINE_bool(force_marking_deque_overflows, false,
"force overflows of marking deque by reducing it's size "
"to 64 words")
DEFINE_bool(stress_compaction, false,
"stress the GC compactor to flush out bugs (implies "
"--force_marking_deque_overflows)")
//
// Debug only flags
//
#undef FLAG
#ifdef DEBUG
#define FLAG FLAG_FULL
#else
#define FLAG FLAG_READONLY
#endif
// checks.cc
#ifdef ENABLE_SLOW_ASSERTS
DEFINE_bool(enable_slow_asserts, false,
"enable asserts that are slow to execute")
#endif
// codegen-ia32.cc / codegen-arm.cc / macro-assembler-*.cc
DEFINE_bool(print_source, false, "pretty print source code")
DEFINE_bool(print_builtin_source, false,
"pretty print source code for builtins")
DEFINE_bool(print_ast, false, "print source AST")
DEFINE_bool(print_builtin_ast, false, "print source AST for builtins")
DEFINE_string(stop_at, "", "function name where to insert a breakpoint")
DEFINE_bool(trap_on_abort, false, "replace aborts by breakpoints")
// compiler.cc
DEFINE_bool(print_builtin_scopes, false, "print scopes for builtins")
DEFINE_bool(print_scopes, false, "print scopes")
// contexts.cc
DEFINE_bool(trace_contexts, false, "trace contexts operations")
// heap.cc
DEFINE_bool(gc_greedy, false, "perform GC prior to some allocations")
DEFINE_bool(gc_verbose, false, "print stuff during garbage collection")
DEFINE_bool(heap_stats, false, "report heap statistics before and after GC")
DEFINE_bool(code_stats, false, "report code statistics after GC")
DEFINE_bool(verify_native_context_separation, false,
"verify that code holds on to at most one native context after GC")
DEFINE_bool(print_handles, false, "report handles after GC")
DEFINE_bool(print_global_handles, false, "report global handles after GC")
// ic.cc
DEFINE_bool(trace_ic, false, "trace inline cache state transitions")
// interface.cc
DEFINE_bool(print_interfaces, false, "print interfaces")
DEFINE_bool(print_interface_details, false, "print interface inference details")
DEFINE_int(print_interface_depth, 5, "depth for printing interfaces")
// objects.cc
DEFINE_bool(trace_normalization, false,
"prints when objects are turned into dictionaries.")
// runtime.cc
DEFINE_bool(trace_lazy, false, "trace lazy compilation")
// spaces.cc
DEFINE_bool(collect_heap_spill_statistics, false,
"report heap spill statistics along with heap_stats "
"(requires heap_stats)")
DEFINE_bool(trace_isolates, false, "trace isolate state changes")
// Regexp
DEFINE_bool(regexp_possessive_quantifier, false,
"enable possessive quantifier syntax for testing")
DEFINE_bool(trace_regexp_bytecodes, false, "trace regexp bytecode execution")
DEFINE_bool(trace_regexp_assembler, false,
"trace regexp macro assembler calls.")
//
// Logging and profiling flags
//
#undef FLAG
#define FLAG FLAG_FULL
// log.cc
DEFINE_bool(log, false,
"Minimal logging (no API, code, GC, suspect, or handles samples).")
DEFINE_bool(log_all, false, "Log all events to the log file.")
DEFINE_bool(log_runtime, false, "Activate runtime system %Log call.")
DEFINE_bool(log_api, false, "Log API events to the log file.")
DEFINE_bool(log_code, false,
"Log code events to the log file without profiling.")
DEFINE_bool(log_gc, false,
"Log heap samples on garbage collection for the hp2ps tool.")
DEFINE_bool(log_handles, false, "Log global handle events.")
DEFINE_bool(log_snapshot_positions, false,
"log positions of (de)serialized objects in the snapshot.")
DEFINE_bool(log_suspect, false, "Log suspect operations.")
DEFINE_bool(prof, false,
"Log statistical profiling information (implies --log-code).")
DEFINE_bool(prof_browser_mode, true,
"Used with --prof, turns on browser-compatible mode for profiling.")
DEFINE_bool(log_regexp, false, "Log regular expression execution.")
DEFINE_string(logfile, "v8.log", "Specify the name of the log file.")
DEFINE_bool(logfile_per_isolate, true, "Separate log files for each isolate.")
DEFINE_bool(ll_prof, false, "Enable low-level linux profiler.")
DEFINE_bool(perf_basic_prof, false,
"Enable perf linux profiler (basic support).")
DEFINE_bool(perf_jit_prof, false,
"Enable perf linux profiler (experimental annotate support).")
DEFINE_string(gc_fake_mmap, "/tmp/__v8_gc__",
"Specify the name of the file for fake gc mmap used in ll_prof")
DEFINE_bool(log_internal_timer_events, false, "Time internal events.")
DEFINE_bool(log_timer_events, false,
"Time events including external callbacks.")
DEFINE_implication(log_timer_events, log_internal_timer_events)
DEFINE_implication(log_internal_timer_events, prof)
DEFINE_bool(log_instruction_stats, false, "Log AArch64 instruction statistics.")
DEFINE_string(log_instruction_file, "a64_inst.csv",
"AArch64 instruction statistics log file.")
DEFINE_int(log_instruction_period, 1 << 22,
"AArch64 instruction statistics logging period.")
DEFINE_bool(redirect_code_traces, false,
"output deopt information and disassembly into file "
"code-<pid>-<isolate id>.asm")
DEFINE_string(redirect_code_traces_to, NULL,
"output deopt information and disassembly into the given file")
DEFINE_bool(hydrogen_track_positions, false,
"track source code positions when building IR")
//
// Disassembler only flags
//
#undef FLAG
#ifdef ENABLE_DISASSEMBLER
#define FLAG FLAG_FULL
#else
#define FLAG FLAG_READONLY
#endif
// elements.cc
DEFINE_bool(trace_elements_transitions, false, "trace elements transitions")
DEFINE_bool(trace_creation_allocation_sites, false,
"trace the creation of allocation sites")
// code-stubs.cc
DEFINE_bool(print_code_stubs, false, "print code stubs")
DEFINE_bool(test_secondary_stub_cache, false,
"test secondary stub cache by disabling the primary one")
DEFINE_bool(test_primary_stub_cache, false,
"test primary stub cache by disabling the secondary one")
// codegen-ia32.cc / codegen-arm.cc
DEFINE_bool(print_code, false, "print generated code")
DEFINE_bool(print_opt_code, false, "print optimized code")
DEFINE_bool(print_unopt_code, false, "print unoptimized code before "
"printing optimized code based on it")
DEFINE_bool(print_code_verbose, false, "print more information for code")
DEFINE_bool(print_builtin_code, false, "print generated code for builtins")
#ifdef ENABLE_DISASSEMBLER
DEFINE_bool(sodium, false, "print generated code output suitable for use with "
"the Sodium code viewer")
DEFINE_implication(sodium, print_code_stubs)
DEFINE_implication(sodium, print_code)
DEFINE_implication(sodium, print_opt_code)
DEFINE_implication(sodium, hydrogen_track_positions)
DEFINE_implication(sodium, code_comments)
DEFINE_bool(print_all_code, false, "enable all flags related to printing code")
DEFINE_implication(print_all_code, print_code)
DEFINE_implication(print_all_code, print_opt_code)
DEFINE_implication(print_all_code, print_unopt_code)
DEFINE_implication(print_all_code, print_code_verbose)
DEFINE_implication(print_all_code, print_builtin_code)
DEFINE_implication(print_all_code, print_code_stubs)
DEFINE_implication(print_all_code, code_comments)
#ifdef DEBUG
DEFINE_implication(print_all_code, trace_codegen)
#endif
#endif
//
// Read-only flags
//
#undef FLAG
#define FLAG FLAG_READONLY
// assembler-arm.h
DEFINE_bool(enable_ool_constant_pool, false,
"enable use of out-of-line constant pools (ARM only)")
// Cleanup...
#undef FLAG_FULL
#undef FLAG_READONLY
#undef FLAG
#undef FLAG_ALIAS
#undef DEFINE_bool
#undef DEFINE_maybe_bool
#undef DEFINE_int
#undef DEFINE_string
#undef DEFINE_float
#undef DEFINE_args
#undef DEFINE_implication
#undef DEFINE_neg_implication
#undef DEFINE_ALIAS_bool
#undef DEFINE_ALIAS_int
#undef DEFINE_ALIAS_string
#undef DEFINE_ALIAS_float
#undef DEFINE_ALIAS_args
#undef FLAG_MODE_DECLARE
#undef FLAG_MODE_DEFINE
#undef FLAG_MODE_DEFINE_DEFAULTS
#undef FLAG_MODE_META
#undef FLAG_MODE_DEFINE_IMPLICATIONS
#undef COMMA