--verify-predictable mode added for ensuring that GC behaves deterministically.

src/flag-definitions.h

 // 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
@@ skipping 842 matching lines @@
 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
 
+
+//
+// VERIFY_PREDICTABLE related flags
+//
+#undef FLAG
+
+#ifdef VERIFY_PREDICTABLE
+#define FLAG FLAG_FULL
+#else
+#define FLAG FLAG_READONLY
+#endif
+
+DEFINE_bool(verify_predictable, false,
+            "this mode is used for checking that V8 behaves predictably")
+DEFINE_bool(allocations_digest, false,

[Hannes Payer (out of office), 2014/06/09 15:23:51]

Do we need both, verify_predictable and allocations_digest? It seems like that
unifying both modes in verify_predictable is good enough?

[Igor Sheludko, 2014/06/10 08:22:54]

Done.

+           "calculate hash over all allocations performed during program "
+           "execution")
+DEFINE_int(dump_allocations_digest_at_alloc, 0,
+          "dump allocations digest each n-th allocation")
+#ifdef VERIFY_PREDICTABLE
+DEFINE_implication(verify_predictable, allocations_digest)
+DEFINE_implication(dump_allocations_digest_at_alloc != 0, allocations_digest)
+#endif
+
+
 //
 // Read-only flags
 //
 #undef FLAG
 #define FLAG FLAG_READONLY
 
 // assembler-arm.h
 DEFINE_bool(enable_ool_constant_pool, V8_OOL_CONSTANT_POOL,
             "enable use of out-of-line constant pools (ARM only)")
 
@@ skipping 17 matching lines @@
 #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