V8Binding/v8/src/compiler.cc - platform/external/webkit - Git at Google

 // Copyright 2009 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.

 #include "v8.h"

 #include "bootstrapper.h"
 #include "codegen-inl.h"
 #include "compilation-cache.h"
 #include "compiler.h"
 #include "debug.h"
 #include "oprofile-agent.h"
 #include "rewriter.h"
 #include "scopes.h"
 #include "usage-analyzer.h"

 namespace v8 {
 namespace internal {

 static Handle<Code> MakeCode(FunctionLiteral* literal,
                              Handle<Script> script,
                              Handle<Context> context,
                              bool is_eval) {
   ASSERT(literal != NULL);

   // Rewrite the AST by introducing .result assignments where needed.
   if (!Rewriter::Process(literal) || !AnalyzeVariableUsage(literal)) {
     // Signal a stack overflow by returning a null handle.  The stack
     // overflow exception will be thrown by the caller.
     return Handle<Code>::null();
   }

   {
     // Compute top scope and allocate variables. For lazy compilation
     // the top scope only contains the single lazily compiled function,
     // so this doesn't re-allocate variables repeatedly.
     HistogramTimerScope timer(&Counters::variable_allocation);
     Scope* top = literal->scope();
     while (top->outer_scope() != NULL) top = top->outer_scope();
     top->AllocateVariables(context);
   }

 #ifdef DEBUG
   if (Bootstrapper::IsActive() ?
       FLAG_print_builtin_scopes :
       FLAG_print_scopes) {
     literal->scope()->Print();
   }
 #endif

   // Optimize the AST.
   if (!Rewriter::Optimize(literal)) {
     // Signal a stack overflow by returning a null handle.  The stack
     // overflow exception will be thrown by the caller.
     return Handle<Code>::null();
   }

   // Generate code and return it.
   Handle<Code> result = CodeGenerator::MakeCode(literal, script, is_eval);
   return result;
 }


 static bool IsValidJSON(FunctionLiteral* lit) {
   if (!lit->body()->length() == 1)
     return false;
   Statement* stmt = lit->body()->at(0);
   if (stmt->AsExpressionStatement() == NULL)
     return false;
   Expression* expr = stmt->AsExpressionStatement()->expression();
   return expr->IsValidJSON();
 }


 static Handle<JSFunction> MakeFunction(bool is_global,
                                        bool is_eval,
                                        bool is_json,
                                        Handle<Script> script,
                                        Handle<Context> context,
                                        v8::Extension* extension,
                                        ScriptDataImpl* pre_data) {
   CompilationZoneScope zone_scope(DELETE_ON_EXIT);

   // Make sure we have an initial stack limit.
   StackGuard guard;
   PostponeInterruptsScope postpone;

   ASSERT(!i::Top::global_context().is_null());
   script->set_context_data((*i::Top::global_context())->data());

 #ifdef ENABLE_DEBUGGER_SUPPORT
   if (is_eval || is_json) {
     script->set_compilation_type(
         is_json ? Smi::FromInt(Script::COMPILATION_TYPE_JSON) :
                                Smi::FromInt(Script::COMPILATION_TYPE_EVAL));
     // For eval scripts add information on the function from which eval was
     // called.
     if (is_eval) {
       JavaScriptFrameIterator it;
       script->set_eval_from_function(it.frame()->function());
       int offset = it.frame()->pc() - it.frame()->code()->instruction_start();
       script->set_eval_from_instructions_offset(Smi::FromInt(offset));
     }
   }

   // Notify debugger
   Debugger::OnBeforeCompile(script);
 #endif

   // Only allow non-global compiles for eval.
   ASSERT(is_eval || is_global);

   // Build AST.
   FunctionLiteral* lit = MakeAST(is_global, script, extension, pre_data);

   // Check for parse errors.
   if (lit == NULL) {
     ASSERT(Top::has_pending_exception());
     return Handle<JSFunction>::null();
   }

   // When parsing JSON we do an ordinary parse and then afterwards
   // check the AST to ensure it was well-formed.  If not we give a
   // syntax error.
   if (is_json && !IsValidJSON(lit)) {
     HandleScope scope;
     Handle<JSArray> args = Factory::NewJSArray(1);
     Handle<Object> source(script->source());
     SetElement(args, 0, source);
     Handle<Object> result = Factory::NewSyntaxError("invalid_json", args);
     Top::Throw(*result, NULL);
     return Handle<JSFunction>::null();
   }

   // Measure how long it takes to do the compilation; only take the
   // rest of the function into account to avoid overlap with the
   // parsing statistics.
   HistogramTimer* rate = is_eval
       ? &Counters::compile_eval
       : &Counters::compile;
   HistogramTimerScope timer(rate);

   // Compile the code.
   Handle<Code> code = MakeCode(lit, script, context, is_eval);

   // Check for stack-overflow exceptions.
   if (code.is_null()) {
     Top::StackOverflow();
     return Handle<JSFunction>::null();
   }

 #if defined ENABLE_LOGGING_AND_PROFILING || defined ENABLE_OPROFILE_AGENT
   // Log the code generation for the script. Check explicit whether logging is
   // to avoid allocating when not required.
   if (Logger::IsEnabled() || OProfileAgent::is_enabled()) {
     if (script->name()->IsString()) {
       SmartPointer<char> data =
           String::cast(script->name())->ToCString(DISALLOW_NULLS);
       LOG(CodeCreateEvent(is_eval ? "Eval" : "Script", *code, *data));
       OProfileAgent::CreateNativeCodeRegion(*data, code->address(),
                                             code->ExecutableSize());
     } else {
       LOG(CodeCreateEvent(is_eval ? "Eval" : "Script", *code, ""));
       OProfileAgent::CreateNativeCodeRegion(is_eval ? "Eval" : "Script",
           code->address(), code->ExecutableSize());
     }
   }
 #endif

   // Allocate function.
   Handle<JSFunction> fun =
       Factory::NewFunctionBoilerplate(lit->name(),
                                       lit->materialized_literal_count(),
                                       lit->contains_array_literal(),
                                       code);

   CodeGenerator::SetFunctionInfo(fun, lit->scope()->num_parameters(),
                                  RelocInfo::kNoPosition,
                                  lit->start_position(), lit->end_position(),
                                  lit->is_expression(), true, script,
                                  lit->inferred_name());

   // Hint to the runtime system used when allocating space for initial
   // property space by setting the expected number of properties for
   // the instances of the function.
   SetExpectedNofPropertiesFromEstimate(fun, lit->expected_property_count());

 #ifdef ENABLE_DEBUGGER_SUPPORT
   // Notify debugger
   Debugger::OnAfterCompile(script, fun);
 #endif

   return fun;
 }


 static StaticResource<SafeStringInputBuffer> safe_string_input_buffer;


 Handle<JSFunction> Compiler::Compile(Handle<String> source,
                                      Handle<Object> script_name,
                                      int line_offset, int column_offset,
                                      v8::Extension* extension,
                                      ScriptDataImpl* input_pre_data) {
   int source_length = source->length();
   Counters::total_load_size.Increment(source_length);
   Counters::total_compile_size.Increment(source_length);

   // The VM is in the COMPILER state until exiting this function.
   VMState state(COMPILER);

   // Do a lookup in the compilation cache but not for extensions.
   Handle<JSFunction> result;
   if (extension == NULL) {
     result = CompilationCache::LookupScript(source,
                                             script_name,
                                             line_offset,
                                             column_offset);
   }

   if (result.is_null()) {
     // No cache entry found. Do pre-parsing and compile the script.
     ScriptDataImpl* pre_data = input_pre_data;
     if (pre_data == NULL && source_length >= FLAG_min_preparse_length) {
       Access<SafeStringInputBuffer> buf(&safe_string_input_buffer);
       buf->Reset(source.location());
       pre_data = PreParse(buf.value(), extension);
     }

     // Create a script object describing the script to be compiled.
     Handle<Script> script = Factory::NewScript(source);
     if (!script_name.is_null()) {
       script->set_name(*script_name);
       script->set_line_offset(Smi::FromInt(line_offset));
       script->set_column_offset(Smi::FromInt(column_offset));
     }

     // Compile the function and add it to the cache.
     result = MakeFunction(true,
                           false,
                           false,
                           script,
                           Handle<Context>::null(),
                           extension,
                           pre_data);
     if (extension == NULL && !result.is_null()) {
       CompilationCache::PutScript(source, result);
     }

     // Get rid of the pre-parsing data (if necessary).
     if (input_pre_data == NULL && pre_data != NULL) {
       delete pre_data;
     }
   }

   if (result.is_null()) Top::ReportPendingMessages();
   return result;
 }


 Handle<JSFunction> Compiler::CompileEval(Handle<String> source,
                                          Handle<Context> context,
                                          bool is_global,
                                          bool is_json) {
   int source_length = source->length();
   Counters::total_eval_size.Increment(source_length);
   Counters::total_compile_size.Increment(source_length);

   // The VM is in the COMPILER state until exiting this function.
   VMState state(COMPILER);
   CompilationCache::Entry entry = is_global
       ? CompilationCache::EVAL_GLOBAL
       : CompilationCache::EVAL_CONTEXTUAL;

   // Do a lookup in the compilation cache; if the entry is not there,
   // invoke the compiler and add the result to the cache.
   Handle<JSFunction> result =
       CompilationCache::LookupEval(source, context, entry);
   if (result.is_null()) {
     // Create a script object describing the script to be compiled.
     Handle<Script> script = Factory::NewScript(source);
     result = MakeFunction(is_global,
                           true,
                           is_json,
                           script,
                           context,
                           NULL,
                           NULL);
     if (!result.is_null()) {
       CompilationCache::PutEval(source, context, entry, result);
     }
   }

   return result;
 }


 bool Compiler::CompileLazy(Handle<SharedFunctionInfo> shared,
                            int loop_nesting) {
   CompilationZoneScope zone_scope(DELETE_ON_EXIT);

   // The VM is in the COMPILER state until exiting this function.
   VMState state(COMPILER);

   // Make sure we have an initial stack limit.
   StackGuard guard;
   PostponeInterruptsScope postpone;

   // Compute name, source code and script data.
   Handle<String> name(String::cast(shared->name()));
   Handle<Script> script(Script::cast(shared->script()));

   int start_position = shared->start_position();
   int end_position = shared->end_position();
   bool is_expression = shared->is_expression();
   Counters::total_compile_size.Increment(end_position - start_position);

   // Generate the AST for the lazily compiled function. The AST may be
   // NULL in case of parser stack overflow.
   FunctionLiteral* lit = MakeLazyAST(script, name,
                                      start_position,
                                      end_position,
                                      is_expression);

   // Check for parse errors.
   if (lit == NULL) {
     ASSERT(Top::has_pending_exception());
     return false;
   }

   // Update the loop nesting in the function literal.
   lit->set_loop_nesting(loop_nesting);

   // Measure how long it takes to do the lazy compilation; only take
   // the rest of the function into account to avoid overlap with the
   // lazy parsing statistics.
   HistogramTimerScope timer(&Counters::compile_lazy);

   // Compile the code.
   Handle<Code> code = MakeCode(lit, script, Handle<Context>::null(), false);

   // Check for stack-overflow exception.
   if (code.is_null()) {
     Top::StackOverflow();
     return false;
   }

 #if defined ENABLE_LOGGING_AND_PROFILING || defined ENABLE_OPROFILE_AGENT
   // Log the code generation. If source information is available include script
   // name and line number. Check explicit whether logging is enabled as finding
   // the line number is not for free.
   if (Logger::IsEnabled() || OProfileAgent::is_enabled()) {
     Handle<String> func_name(name->length() > 0 ?
                              *name : shared->inferred_name());
     if (script->name()->IsString()) {
       int line_num = GetScriptLineNumber(script, start_position);
       if (line_num > 0) {
         line_num += script->line_offset()->value() + 1;
       }
       LOG(CodeCreateEvent("LazyCompile", *code, *func_name,
                           String::cast(script->name()), line_num));
       OProfileAgent::CreateNativeCodeRegion(*func_name,
                                             String::cast(script->name()),
                                             line_num, code->address(),
                                             code->ExecutableSize());
     } else {
       LOG(CodeCreateEvent("LazyCompile", *code, *func_name));
       OProfileAgent::CreateNativeCodeRegion(*func_name, code->address(),
                                             code->ExecutableSize());
     }
   }
 #endif

   // Update the shared function info with the compiled code.
   shared->set_code(*code);

   // Set the expected number of properties for instances.
   SetExpectedNofPropertiesFromEstimate(shared, lit->expected_property_count());

   // Check the function has compiled code.
   ASSERT(shared->is_compiled());
   return true;
 }


 } }  // namespace v8::internal
	// Copyright 2009 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.

	#include "v8.h"

	#include "bootstrapper.h"
	#include "codegen-inl.h"
	#include "compilation-cache.h"
	#include "compiler.h"
	#include "debug.h"
	#include "oprofile-agent.h"
	#include "rewriter.h"
	#include "scopes.h"
	#include "usage-analyzer.h"

	namespace v8 {
	namespace internal {

	static Handle<Code> MakeCode(FunctionLiteral* literal,
	Handle<Script> script,
	Handle<Context> context,
	bool is_eval) {
	ASSERT(literal != NULL);

	// Rewrite the AST by introducing .result assignments where needed.
	if (!Rewriter::Process(literal) \|\| !AnalyzeVariableUsage(literal)) {
	// Signal a stack overflow by returning a null handle. The stack
	// overflow exception will be thrown by the caller.
	return Handle<Code>::null();
	}

	{
	// Compute top scope and allocate variables. For lazy compilation
	// the top scope only contains the single lazily compiled function,
	// so this doesn't re-allocate variables repeatedly.
	HistogramTimerScope timer(&Counters::variable_allocation);
	Scope* top = literal->scope();
	while (top->outer_scope() != NULL) top = top->outer_scope();
	top->AllocateVariables(context);
	}

	#ifdef DEBUG
	if (Bootstrapper::IsActive() ?
	FLAG_print_builtin_scopes :
	FLAG_print_scopes) {
	literal->scope()->Print();
	}
	#endif

	// Optimize the AST.
	if (!Rewriter::Optimize(literal)) {
	// Signal a stack overflow by returning a null handle. The stack
	// overflow exception will be thrown by the caller.
	return Handle<Code>::null();
	}

	// Generate code and return it.
	Handle<Code> result = CodeGenerator::MakeCode(literal, script, is_eval);
	return result;
	}


	static bool IsValidJSON(FunctionLiteral* lit) {
	if (!lit->body()->length() == 1)
	return false;
	Statement* stmt = lit->body()->at(0);
	if (stmt->AsExpressionStatement() == NULL)
	return false;
	Expression* expr = stmt->AsExpressionStatement()->expression();
	return expr->IsValidJSON();
	}


	static Handle<JSFunction> MakeFunction(bool is_global,
	bool is_eval,
	bool is_json,
	Handle<Script> script,
	Handle<Context> context,
	v8::Extension* extension,
	ScriptDataImpl* pre_data) {
	CompilationZoneScope zone_scope(DELETE_ON_EXIT);

	// Make sure we have an initial stack limit.
	StackGuard guard;
	PostponeInterruptsScope postpone;

	ASSERT(!i::Top::global_context().is_null());
	script->set_context_data((*i::Top::global_context())->data());

	#ifdef ENABLE_DEBUGGER_SUPPORT
	if (is_eval \|\| is_json) {
	script->set_compilation_type(
	is_json ? Smi::FromInt(Script::COMPILATION_TYPE_JSON) :
	Smi::FromInt(Script::COMPILATION_TYPE_EVAL));
	// For eval scripts add information on the function from which eval was
	// called.
	if (is_eval) {
	JavaScriptFrameIterator it;
	script->set_eval_from_function(it.frame()->function());
	int offset = it.frame()->pc() - it.frame()->code()->instruction_start();
	script->set_eval_from_instructions_offset(Smi::FromInt(offset));
	}
	}

	// Notify debugger
	Debugger::OnBeforeCompile(script);
	#endif

	// Only allow non-global compiles for eval.
	ASSERT(is_eval \|\| is_global);

	// Build AST.
	FunctionLiteral* lit = MakeAST(is_global, script, extension, pre_data);

	// Check for parse errors.
	if (lit == NULL) {
	ASSERT(Top::has_pending_exception());
	return Handle<JSFunction>::null();
	}

	// When parsing JSON we do an ordinary parse and then afterwards
	// check the AST to ensure it was well-formed. If not we give a
	// syntax error.
	if (is_json && !IsValidJSON(lit)) {
	HandleScope scope;
	Handle<JSArray> args = Factory::NewJSArray(1);
	Handle<Object> source(script->source());
	SetElement(args, 0, source);
	Handle<Object> result = Factory::NewSyntaxError("invalid_json", args);
	Top::Throw(*result, NULL);
	return Handle<JSFunction>::null();
	}

	// Measure how long it takes to do the compilation; only take the
	// rest of the function into account to avoid overlap with the
	// parsing statistics.
	HistogramTimer* rate = is_eval
	? &Counters::compile_eval
	: &Counters::compile;
	HistogramTimerScope timer(rate);

	// Compile the code.
	Handle<Code> code = MakeCode(lit, script, context, is_eval);

	// Check for stack-overflow exceptions.
	if (code.is_null()) {
	Top::StackOverflow();
	return Handle<JSFunction>::null();
	}

	#if defined ENABLE_LOGGING_AND_PROFILING \|\| defined ENABLE_OPROFILE_AGENT
	// Log the code generation for the script. Check explicit whether logging is
	// to avoid allocating when not required.
	if (Logger::IsEnabled() \|\| OProfileAgent::is_enabled()) {
	if (script->name()->IsString()) {
	SmartPointer<char> data =
	String::cast(script->name())->ToCString(DISALLOW_NULLS);
	LOG(CodeCreateEvent(is_eval ? "Eval" : "Script", code, data));
	OProfileAgent::CreateNativeCodeRegion(*data, code->address(),
	code->ExecutableSize());
	} else {
	LOG(CodeCreateEvent(is_eval ? "Eval" : "Script", *code, ""));
	OProfileAgent::CreateNativeCodeRegion(is_eval ? "Eval" : "Script",
	code->address(), code->ExecutableSize());
	}
	}
	#endif

	// Allocate function.
	Handle<JSFunction> fun =
	Factory::NewFunctionBoilerplate(lit->name(),
	lit->materialized_literal_count(),
	lit->contains_array_literal(),
	code);

	CodeGenerator::SetFunctionInfo(fun, lit->scope()->num_parameters(),
	RelocInfo::kNoPosition,
	lit->start_position(), lit->end_position(),
	lit->is_expression(), true, script,
	lit->inferred_name());

	// Hint to the runtime system used when allocating space for initial
	// property space by setting the expected number of properties for
	// the instances of the function.
	SetExpectedNofPropertiesFromEstimate(fun, lit->expected_property_count());

	#ifdef ENABLE_DEBUGGER_SUPPORT
	// Notify debugger
	Debugger::OnAfterCompile(script, fun);
	#endif

	return fun;
	}


	static StaticResource<SafeStringInputBuffer> safe_string_input_buffer;


	Handle<JSFunction> Compiler::Compile(Handle<String> source,
	Handle<Object> script_name,
	int line_offset, int column_offset,
	v8::Extension* extension,
	ScriptDataImpl* input_pre_data) {
	int source_length = source->length();
	Counters::total_load_size.Increment(source_length);
	Counters::total_compile_size.Increment(source_length);

	// The VM is in the COMPILER state until exiting this function.
	VMState state(COMPILER);

	// Do a lookup in the compilation cache but not for extensions.
	Handle<JSFunction> result;
	if (extension == NULL) {
	result = CompilationCache::LookupScript(source,
	script_name,
	line_offset,
	column_offset);
	}

	if (result.is_null()) {
	// No cache entry found. Do pre-parsing and compile the script.
	ScriptDataImpl* pre_data = input_pre_data;
	if (pre_data == NULL && source_length >= FLAG_min_preparse_length) {
	Access<SafeStringInputBuffer> buf(&safe_string_input_buffer);
	buf->Reset(source.location());
	pre_data = PreParse(buf.value(), extension);
	}

	// Create a script object describing the script to be compiled.
	Handle<Script> script = Factory::NewScript(source);
	if (!script_name.is_null()) {
	script->set_name(*script_name);
	script->set_line_offset(Smi::FromInt(line_offset));
	script->set_column_offset(Smi::FromInt(column_offset));
	}

	// Compile the function and add it to the cache.
	result = MakeFunction(true,
	false,
	false,
	script,
	Handle<Context>::null(),
	extension,
	pre_data);
	if (extension == NULL && !result.is_null()) {
	CompilationCache::PutScript(source, result);
	}

	// Get rid of the pre-parsing data (if necessary).
	if (input_pre_data == NULL && pre_data != NULL) {
	delete pre_data;
	}
	}

	if (result.is_null()) Top::ReportPendingMessages();
	return result;
	}


	Handle<JSFunction> Compiler::CompileEval(Handle<String> source,
	Handle<Context> context,
	bool is_global,
	bool is_json) {
	int source_length = source->length();
	Counters::total_eval_size.Increment(source_length);
	Counters::total_compile_size.Increment(source_length);

	// The VM is in the COMPILER state until exiting this function.
	VMState state(COMPILER);
	CompilationCache::Entry entry = is_global
	? CompilationCache::EVAL_GLOBAL
	: CompilationCache::EVAL_CONTEXTUAL;

	// Do a lookup in the compilation cache; if the entry is not there,
	// invoke the compiler and add the result to the cache.
	Handle<JSFunction> result =
	CompilationCache::LookupEval(source, context, entry);
	if (result.is_null()) {
	// Create a script object describing the script to be compiled.
	Handle<Script> script = Factory::NewScript(source);
	result = MakeFunction(is_global,
	true,
	is_json,
	script,
	context,
	NULL,
	NULL);
	if (!result.is_null()) {
	CompilationCache::PutEval(source, context, entry, result);
	}
	}

	return result;
	}


	bool Compiler::CompileLazy(Handle<SharedFunctionInfo> shared,
	int loop_nesting) {
	CompilationZoneScope zone_scope(DELETE_ON_EXIT);

	// The VM is in the COMPILER state until exiting this function.
	VMState state(COMPILER);

	// Make sure we have an initial stack limit.
	StackGuard guard;
	PostponeInterruptsScope postpone;

	// Compute name, source code and script data.
	Handle<String> name(String::cast(shared->name()));
	Handle<Script> script(Script::cast(shared->script()));

	int start_position = shared->start_position();
	int end_position = shared->end_position();
	bool is_expression = shared->is_expression();
	Counters::total_compile_size.Increment(end_position - start_position);

	// Generate the AST for the lazily compiled function. The AST may be
	// NULL in case of parser stack overflow.
	FunctionLiteral* lit = MakeLazyAST(script, name,
	start_position,
	end_position,
	is_expression);

	// Check for parse errors.
	if (lit == NULL) {
	ASSERT(Top::has_pending_exception());
	return false;
	}

	// Update the loop nesting in the function literal.
	lit->set_loop_nesting(loop_nesting);

	// Measure how long it takes to do the lazy compilation; only take
	// the rest of the function into account to avoid overlap with the
	// lazy parsing statistics.
	HistogramTimerScope timer(&Counters::compile_lazy);

	// Compile the code.
	Handle<Code> code = MakeCode(lit, script, Handle<Context>::null(), false);

	// Check for stack-overflow exception.
	if (code.is_null()) {
	Top::StackOverflow();
	return false;
	}

	#if defined ENABLE_LOGGING_AND_PROFILING \|\| defined ENABLE_OPROFILE_AGENT
	// Log the code generation. If source information is available include script
	// name and line number. Check explicit whether logging is enabled as finding
	// the line number is not for free.
	if (Logger::IsEnabled() \|\| OProfileAgent::is_enabled()) {
	Handle<String> func_name(name->length() > 0 ?
	*name : shared->inferred_name());
	if (script->name()->IsString()) {
	int line_num = GetScriptLineNumber(script, start_position);
	if (line_num > 0) {
	line_num += script->line_offset()->value() + 1;
	}
	LOG(CodeCreateEvent("LazyCompile", code, func_name,
	String::cast(script->name()), line_num));
	OProfileAgent::CreateNativeCodeRegion(*func_name,
	String::cast(script->name()),
	line_num, code->address(),
	code->ExecutableSize());
	} else {
	LOG(CodeCreateEvent("LazyCompile", code, func_name));
	OProfileAgent::CreateNativeCodeRegion(*func_name, code->address(),
	code->ExecutableSize());
	}
	}
	#endif

	// Update the shared function info with the compiled code.
	shared->set_code(*code);

	// Set the expected number of properties for instances.
	SetExpectedNofPropertiesFromEstimate(shared, lit->expected_property_count());

	// Check the function has compiled code.
	ASSERT(shared->is_compiled());
	return true;
	}


	} } // namespace v8::internal