Remove some unused and unneeded flags.

src/flag-definitions.h

 // Copyright 2011 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
@@ skipping 282 matching lines @@
 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_int(random_seed, 0,
            "Default seed for initializing random generator "
            "(0, the default, means to use system random).")
 
 DEFINE_bool(canonicalize_object_literal_maps, true,
             "Canonicalize maps for object literals.")
 
-DEFINE_bool(use_big_map_space, true,
-            "Use big map space, but don't compact if it grew too big.")
-
 DEFINE_int(max_map_space_pages, MapSpace::kMaxMapPageIndex - 1,
            "Maximum number of pages in map space which still allows to encode "
            "forwarding pointers.  That's actually a constant, but it's useful "
            "to control it with a flag for better testing.")
 
 // mksnapshot.cc
 DEFINE_bool(h, false, "print this message")
 DEFINE_bool(new_snapshot, true, "use new snapshot implementation")
 
 // objects.cc
@@ skipping 15 matching lines @@
             "print stack trace when throwing exceptions")
 DEFINE_bool(preallocate_message_memory, false,
             "preallocate some memory to build stack traces.")
 
 // v8.cc
 DEFINE_bool(preemption, false,
             "activate a 100ms timer that switches between V8 threads")
 
 // Regexp
 DEFINE_bool(regexp_optimization, true, "generate optimized regexp code")
-DEFINE_bool(regexp_entry_native, true, "use native code to enter regexp")
 
 // Testing flags test/cctest/test-{flags,api,serialization}.cc
 DEFINE_bool(testing_bool_flag, true, "testing_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")
@@ skipping 106 matching lines @@
 DEFINE_bool(debug_serialization, false,
             "write debug information into the snapshot.")
 
 // 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")
 
-DEFINE_bool(trace_live_byte_count, false,
-            "trace updates to page live byte count")
-
 // VM state
 DEFINE_bool(log_state_changes, false, "Log 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,
@@ skipping 61 matching lines @@
 #undef FLAG
 
 #undef DEFINE_bool
 #undef DEFINE_int
 #undef DEFINE_string
 
 #undef FLAG_MODE_DECLARE
 #undef FLAG_MODE_DEFINE
 #undef FLAG_MODE_DEFINE_DEFAULTS
 #undef FLAG_MODE_META