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variables.cc
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27 
28 #include "v8.h"
29 
30 #include "ast.h"
31 #include "scopes.h"
32 #include "variables.h"
33 
34 namespace v8 {
35 namespace internal {
36 
37 // ----------------------------------------------------------------------------
38 // Implementation Variable.
39 
41  switch (mode) {
42  case VAR: return "VAR";
43  case CONST_LEGACY: return "CONST_LEGACY";
44  case LET: return "LET";
45  case CONST: return "CONST";
46  case MODULE: return "MODULE";
47  case DYNAMIC: return "DYNAMIC";
48  case DYNAMIC_GLOBAL: return "DYNAMIC_GLOBAL";
49  case DYNAMIC_LOCAL: return "DYNAMIC_LOCAL";
50  case INTERNAL: return "INTERNAL";
51  case TEMPORARY: return "TEMPORARY";
52  }
53  UNREACHABLE();
54  return NULL;
55 }
56 
57 
61  bool is_valid_LHS,
62  Kind kind,
63  InitializationFlag initialization_flag,
65  : scope_(scope),
66  name_(name),
67  mode_(mode),
68  kind_(kind),
69  location_(UNALLOCATED),
70  index_(-1),
71  initializer_position_(RelocInfo::kNoPosition),
72  local_if_not_shadowed_(NULL),
73  is_valid_LHS_(is_valid_LHS),
74  force_context_allocation_(false),
75  is_used_(false),
76  initialization_flag_(initialization_flag),
77  interface_(interface) {
78  // Names must be canonicalized for fast equality checks.
79  ASSERT(name->IsInternalizedString());
80  // Var declared variables never need initialization.
81  ASSERT(!(mode == VAR && initialization_flag == kNeedsInitialization));
82 }
83 
84 
86  // Temporaries are never global, they must always be allocated in the
87  // activation frame.
88  return (IsDynamicVariableMode(mode_) ||
90  && scope_ != NULL && scope_->is_global_scope();
91 }
92 
93 
94 int Variable::CompareIndex(Variable* const* v, Variable* const* w) {
95  int x = (*v)->index();
96  int y = (*w)->index();
97  // Consider sorting them according to type as well?
98  return x - y;
99 }
100 
101 } } // namespace v8::internal
bool is_global_scope() const
Definition: scopes.h:286
enable upcoming ES6 features enable harmony block scoping enable harmony enable harmony proxies enable harmony generators enable harmony numeric enable harmony string enable harmony math functions harmony_scoping harmony_symbols harmony_collections harmony_iteration harmony_strings harmony_scoping harmony_maths tracks arrays with only smi values Optimize object Array DOM strings and string pretenure call new trace pretenuring decisions of HAllocate instructions track fields with only smi values track fields with heap values track_fields track_fields Enables optimizations which favor memory size over execution speed use string slices optimization filter maximum number of GVN fix point iterations use function inlining use allocation folding eliminate write barriers targeting allocations in optimized code maximum source size in bytes considered for a single inlining maximum cumulative number of AST nodes considered for inlining crankshaft harvests type feedback from stub cache trace check elimination phase hydrogen tracing filter NULL
Definition: flags.cc:269
#define ASSERT(condition)
Definition: checks.h:329
enable upcoming ES6 features enable harmony block scoping enable harmony enable harmony proxies enable harmony generators enable harmony numeric enable harmony string enable harmony math functions harmony_scoping harmony_symbols harmony_collections harmony_iteration harmony_strings harmony_scoping harmony_maths tracks arrays with only smi values Optimize object Array DOM strings and string pretenure call new trace pretenuring decisions of HAllocate instructions track fields with only smi values track fields with heap values track_fields track_fields Enables optimizations which favor memory size over execution speed use string slices optimization filter maximum number of GVN fix point iterations use function inlining use allocation folding eliminate write barriers targeting allocations in optimized code maximum source size in bytes considered for a single inlining maximum cumulative number of AST nodes considered for inlining crankshaft harvests type feedback from stub cache trace check elimination phase hydrogen tracing filter trace hydrogen to given file name trace inlining decisions trace store elimination trace all use positions trace global value numbering trace hydrogen escape analysis trace the tracking of allocation sites trace map generalization environment for every instruction deoptimize every n garbage collections put a break point before deoptimizing deoptimize uncommon cases use on stack replacement trace array bounds check elimination perform array index dehoisting use load elimination use store elimination use constant folding eliminate unreachable code number of stress runs when picking a function to watch for shared function not JSFunction itself flushes the cache of optimized code for closures on every GC functions with arguments object maximum number of escape analysis fix point iterations allow uint32 values on optimize frames if they are used only in safe operations track concurrent recompilation artificial compilation delay in ms concurrent on stack replacement do not emit check maps for constant values that have a leaf deoptimize the optimized code if the layout of the maps changes number of stack frames inspected by the profiler percentage of ICs that must have type info to allow optimization extra verbose compilation tracing generate extra emit comments in code disassembly enable use of SSE3 instructions if available enable use of CMOV instruction if available enable use of VFP3 instructions if available enable use of NEON instructions if enable use of SDIV and UDIV instructions if enable loading bit constant by means of movw movt instruction enable unaligned accesses for enable use of d16 d31 registers on ARM this requires VFP3 force all emitted branches to be in long expose natives in global object expose freeBuffer extension expose gc extension under the specified name expose externalize string extension number of stack frames to capture disable builtin natives files print name of functions for which code is generated use random jit cookie to mask large constants trace lazy optimization use adaptive optimizations always try to OSR functions trace optimize function deoptimization minimum length for automatic enable preparsing maximum number of optimization attempts before giving up cache prototype transitions trace debugging JSON request response trace out of bounds accesses to external arrays trace_js_array_abuse automatically set the debug break flag when debugger commands are in the queue abort by crashing maximum length of function source code printed in a stack trace max size of the new max size of the old max size of executable always perform global GCs print one trace line following each garbage collection do not print trace line after scavenger collection print statistics of the maximum memory committed for the heap in only print modified registers Don t break for ASM_UNIMPLEMENTED_BREAK macros print stack trace when an illegal exception is thrown randomize hashes to avoid predictable hash Fixed seed to use to hash property Print the time it takes to deserialize the snapshot testing_bool_flag testing_int_flag string flag tmp file in which to serialize heap Print the time it takes to lazily compile hydrogen code stubs concurrent_recompilation concurrent_sweeping Print usage including on console Map counters to a file Enable debugger compile events enable GDBJIT interface(disables compacting GC)") DEFINE_bool(gdbjit_full
#define UNREACHABLE()
Definition: checks.h:52
enable upcoming ES6 features enable harmony block scoping enable harmony enable harmony proxies enable harmony generators enable harmony numeric enable harmony string enable harmony math functions harmony_scoping harmony_symbols harmony_collections harmony_iteration harmony_strings harmony_scoping harmony_maths tracks arrays with only smi values Optimize object Array DOM strings and string pretenure call new trace pretenuring decisions of HAllocate instructions track fields with only smi values track fields with heap values track_fields track_fields Enables optimizations which favor memory size over execution speed use string slices optimization filter maximum number of GVN fix point iterations use function inlining use allocation folding eliminate write barriers targeting allocations in optimized code maximum source size in bytes considered for a single inlining maximum cumulative number of AST nodes considered for inlining crankshaft harvests type feedback from stub cache trace check elimination phase hydrogen tracing filter trace hydrogen to given file name trace inlining decisions trace store elimination trace all use positions trace global value numbering trace hydrogen escape analysis trace the tracking of allocation sites trace map generalization environment for every instruction deoptimize every n garbage collections put a break point before deoptimizing deoptimize uncommon cases use on stack replacement trace array bounds check elimination perform array index dehoisting use load elimination use store elimination use constant folding eliminate unreachable code number of stress runs when picking a function to watch for shared function not JSFunction itself flushes the cache of optimized code for closures on every GC functions with arguments object maximum number of escape analysis fix point iterations allow uint32 values on optimize frames if they are used only in safe operations track concurrent recompilation artificial compilation delay in ms concurrent on stack replacement do not emit check maps for constant values that have a leaf deoptimize the optimized code if the layout of the maps changes number of stack frames inspected by the profiler percentage of ICs that must have type info to allow optimization extra verbose compilation tracing generate extra emit comments in code disassembly enable use of SSE3 instructions if available enable use of CMOV instruction if available enable use of VFP3 instructions if available enable use of NEON instructions if enable use of SDIV and UDIV instructions if enable loading bit constant by means of movw movt instruction enable unaligned accesses for enable use of d16 d31 registers on ARM this requires VFP3 force all emitted branches to be in long mode(MIPS only)") DEFINE_string(expose_natives_as
static int CompareIndex(Variable *const *v, Variable *const *w)
Definition: variables.cc:94
bool IsLexicalVariableMode(VariableMode mode)
Definition: v8globals.h:508
static const char * Mode2String(VariableMode mode)
Definition: variables.cc:40
Variable(Scope *scope, Handle< String > name, VariableMode mode, bool is_valid_lhs, Kind kind, InitializationFlag initialization_flag, Interface *interface=Interface::NewValue())
Definition: variables.cc:58
bool IsDeclaredVariableMode(VariableMode mode)
Definition: v8globals.h:503
bool IsDynamicVariableMode(VariableMode mode)
Definition: v8globals.h:498
bool IsGlobalObjectProperty() const
Definition: variables.cc:85
enable upcoming ES6 features enable harmony block scoping enable harmony enable harmony proxies enable harmony generators enable harmony numeric enable harmony string enable harmony math functions harmony_scoping harmony_symbols harmony_collections harmony_iteration harmony_strings harmony_scoping harmony_maths tracks arrays with only smi values Optimize object Array DOM strings and string pretenure call new trace pretenuring decisions of HAllocate instructions track fields with only smi values track fields with heap values track_fields track_fields Enables optimizations which favor memory size over execution speed use string slices optimization filter maximum number of GVN fix point iterations use function inlining use allocation folding eliminate write barriers targeting allocations in optimized code maximum source size in bytes considered for a single inlining maximum cumulative number of AST nodes considered for inlining crankshaft harvests type feedback from stub cache trace check elimination phase hydrogen tracing filter trace hydrogen to given file name trace inlining decisions trace store elimination trace all use positions trace global value numbering trace hydrogen escape analysis trace the tracking of allocation sites trace map generalization environment for every instruction deoptimize every n garbage collections put a break point before deoptimizing deoptimize uncommon cases use on stack replacement trace array bounds check elimination perform array index dehoisting use load elimination use store elimination use constant folding eliminate unreachable code number of stress runs when picking a function to watch for shared function not JSFunction itself flushes the cache of optimized code for closures on every GC functions with arguments object maximum number of escape analysis fix point iterations allow uint32 values on optimize frames if they are used only in safe operations track concurrent recompilation artificial compilation delay in ms concurrent on stack replacement do not emit check maps for constant values that have a leaf deoptimize the optimized code if the layout of the maps changes number of stack frames inspected by the profiler percentage of ICs that must have type info to allow optimization extra verbose compilation tracing generate extra emit comments in code disassembly enable use of SSE3 instructions if available enable use of CMOV instruction if available enable use of VFP3 instructions if available enable use of NEON instructions if enable use of SDIV and UDIV instructions if enable loading bit constant by means of movw movt instruction enable unaligned accesses for enable use of d16 d31 registers on ARM this requires VFP3 force all emitted branches to be in long expose natives in global object expose freeBuffer extension expose gc extension under the specified name expose externalize string extension number of stack frames to capture disable builtin natives files print name of functions for which code is generated use random jit cookie to mask large constants trace lazy optimization use adaptive optimizations always try to OSR functions trace optimize function deoptimization minimum length for automatic enable preparsing maximum number of optimization attempts before giving up cache prototype transitions trace debugging JSON request response trace out of bounds accesses to external arrays trace_js_array_abuse automatically set the debug break flag when debugger commands are in the queue abort by crashing maximum length of function source code printed in a stack trace max size of the new max size of the old max size of executable always perform global GCs print one trace line following each garbage collection do not print trace line after scavenger collection print statistics of the maximum memory committed for the heap in name
Definition: flags.cc:505