| // Copyright 2006-2008 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. |
| |
| #ifndef V8_SCOPEINFO_H_ |
| #define V8_SCOPEINFO_H_ |
| |
| #include "variables.h" |
| |
| namespace v8 { namespace internal { |
| |
| // Scope information represents information about a functions's |
| // scopes (currently only one, because we don't do any inlining) |
| // and the allocation of the scope's variables. Scope information |
| // is stored in a compressed form with Code objects and is used |
| // at runtime (stack dumps, deoptimization, etc.). |
| // |
| // Historical note: In other VMs built by this team, ScopeInfo was |
| // usually called DebugInfo since the information was used (among |
| // other things) for on-demand debugging (Self, Smalltalk). However, |
| // DebugInfo seems misleading, since this information is primarily used |
| // in debugging-unrelated contexts. |
| |
| // Forward defined as |
| // template <class Allocator = FreeStoreAllocationPolicy> class ScopeInfo; |
| template<class Allocator> |
| class ScopeInfo BASE_EMBEDDED { |
| public: |
| // Create a ScopeInfo instance from a scope. |
| explicit ScopeInfo(Scope* scope); |
| |
| // Create a ScopeInfo instance from a Code object. |
| explicit ScopeInfo(Code* code); |
| |
| // Write the ScopeInfo data into a Code object, and returns the |
| // amount of space that was needed. If no Code object is provided |
| // (NULL handle), Serialize() only returns the amount of space needed. |
| // |
| // This operations requires that the Code object has the correct amount |
| // of space for the ScopeInfo data; otherwise the operation fails (fatal |
| // error). Any existing scope info in the Code object is simply overwritten. |
| int Serialize(Code* code); |
| |
| // Garbage collection support for scope info embedded in Code objects. |
| // This code is in ScopeInfo because only here we should have to know |
| // about the encoding. |
| static void IterateScopeInfo(Code* code, ObjectVisitor* v); |
| |
| |
| // -------------------------------------------------------------------------- |
| // Lookup |
| |
| Handle<String> function_name() const { return function_name_; } |
| |
| Handle<String> parameter_name(int i) const { return parameters_[i]; } |
| int number_of_parameters() const { return parameters_.length(); } |
| |
| Handle<String> stack_slot_name(int i) const { return stack_slots_[i]; } |
| int number_of_stack_slots() const { return stack_slots_.length(); } |
| |
| Handle<String> context_slot_name(int i) const { |
| return context_slots_[i - Context::MIN_CONTEXT_SLOTS]; |
| } |
| int number_of_context_slots() const { |
| int l = context_slots_.length(); |
| return l == 0 ? 0 : l + Context::MIN_CONTEXT_SLOTS; |
| } |
| |
| Handle<String> LocalName(int i) const; |
| int NumberOfLocals() const; |
| |
| // -------------------------------------------------------------------------- |
| // The following functions provide quick access to scope info details |
| // for runtime routines w/o the need to explicitly create a ScopeInfo |
| // object. |
| // |
| // ScopeInfo is the only class which should have to know about the |
| // encoding of it's information in a Code object, which is why these |
| // functions are in this class. |
| |
| // Does this scope call eval. |
| static bool CallsEval(Code* code); |
| |
| // Return the number of stack slots for code. |
| static int NumberOfStackSlots(Code* code); |
| |
| // Return the number of context slots for code. |
| static int NumberOfContextSlots(Code* code); |
| |
| // Lookup support for scope info embedded in Code objects. Returns |
| // the stack slot index for a given slot name if the slot is |
| // present; otherwise returns a value < 0. The name must be a symbol |
| // (canonicalized). |
| static int StackSlotIndex(Code* code, String* name); |
| |
| // Lookup support for scope info embedded in Code objects. Returns the |
| // context slot index for a given slot name if the slot is present; otherwise |
| // returns a value < 0. The name must be a symbol (canonicalized). |
| // If the slot is present and mode != NULL, sets *mode to the corresponding |
| // mode for that variable. |
| static int ContextSlotIndex(Code* code, String* name, Variable::Mode* mode); |
| |
| // Lookup support for scope info embedded in Code objects. Returns the |
| // parameter index for a given parameter name if the parameter is present; |
| // otherwise returns a value < 0. The name must be a symbol (canonicalized). |
| static int ParameterIndex(Code* code, String* name); |
| |
| // Lookup support for scope info embedded in Code objects. Returns the |
| // function context slot index if the function name is present (named |
| // function expressions, only), otherwise returns a value < 0. The name |
| // must be a symbol (canonicalized). |
| static int FunctionContextSlotIndex(Code* code, String* name); |
| |
| // -------------------------------------------------------------------------- |
| // Debugging support |
| |
| #ifdef DEBUG |
| void Print(); |
| #endif |
| |
| private: |
| Handle<String> function_name_; |
| bool calls_eval_; |
| List<Handle<String>, Allocator > parameters_; |
| List<Handle<String>, Allocator > stack_slots_; |
| List<Handle<String>, Allocator > context_slots_; |
| List<Variable::Mode, Allocator > context_modes_; |
| }; |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_SCOPEINFO_H_ |