v8/src/compiler.cc
2012-03-26 13:08:08 +00:00

827 lines
31 KiB
C++

// Copyright 2012 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 "compiler.h"
#include "bootstrapper.h"
#include "codegen.h"
#include "compilation-cache.h"
#include "debug.h"
#include "full-codegen.h"
#include "gdb-jit.h"
#include "hydrogen.h"
#include "isolate-inl.h"
#include "lithium.h"
#include "liveedit.h"
#include "parser.h"
#include "rewriter.h"
#include "runtime-profiler.h"
#include "scanner-character-streams.h"
#include "scopeinfo.h"
#include "scopes.h"
#include "vm-state-inl.h"
namespace v8 {
namespace internal {
CompilationInfo::CompilationInfo(Handle<Script> script)
: isolate_(script->GetIsolate()),
flags_(LanguageModeField::encode(CLASSIC_MODE)),
function_(NULL),
scope_(NULL),
global_scope_(NULL),
script_(script),
extension_(NULL),
pre_parse_data_(NULL),
osr_ast_id_(AstNode::kNoNumber) {
Initialize(BASE);
}
CompilationInfo::CompilationInfo(Handle<SharedFunctionInfo> shared_info)
: isolate_(shared_info->GetIsolate()),
flags_(LanguageModeField::encode(CLASSIC_MODE) |
IsLazy::encode(true)),
function_(NULL),
scope_(NULL),
global_scope_(NULL),
shared_info_(shared_info),
script_(Handle<Script>(Script::cast(shared_info->script()))),
extension_(NULL),
pre_parse_data_(NULL),
osr_ast_id_(AstNode::kNoNumber) {
Initialize(BASE);
}
CompilationInfo::CompilationInfo(Handle<JSFunction> closure)
: isolate_(closure->GetIsolate()),
flags_(LanguageModeField::encode(CLASSIC_MODE) |
IsLazy::encode(true)),
function_(NULL),
scope_(NULL),
global_scope_(NULL),
closure_(closure),
shared_info_(Handle<SharedFunctionInfo>(closure->shared())),
script_(Handle<Script>(Script::cast(shared_info_->script()))),
extension_(NULL),
pre_parse_data_(NULL),
osr_ast_id_(AstNode::kNoNumber) {
Initialize(BASE);
}
// Disable optimization for the rest of the compilation pipeline.
void CompilationInfo::DisableOptimization() {
bool is_optimizable_closure =
FLAG_optimize_closures &&
closure_.is_null() &&
!scope_->HasTrivialOuterContext() &&
!scope_->outer_scope_calls_non_strict_eval() &&
!scope_->inside_with();
SetMode(is_optimizable_closure ? BASE : NONOPT);
}
// Primitive functions are unlikely to be picked up by the stack-walking
// profiler, so they trigger their own optimization when they're called
// for the SharedFunctionInfo::kCallsUntilPrimitiveOptimization-th time.
bool CompilationInfo::ShouldSelfOptimize() {
return FLAG_self_optimization &&
FLAG_crankshaft &&
!function()->flags()->Contains(kDontSelfOptimize) &&
!function()->flags()->Contains(kDontOptimize) &&
function()->scope()->allows_lazy_recompilation() &&
(shared_info().is_null() || !shared_info()->optimization_disabled());
}
void CompilationInfo::AbortOptimization() {
Handle<Code> code(shared_info()->code());
SetCode(code);
}
// Determine whether to use the full compiler for all code. If the flag
// --always-full-compiler is specified this is the case. For the virtual frame
// based compiler the full compiler is also used if a debugger is connected, as
// the code from the full compiler supports mode precise break points. For the
// crankshaft adaptive compiler debugging the optimized code is not possible at
// all. However crankshaft support recompilation of functions, so in this case
// the full compiler need not be be used if a debugger is attached, but only if
// break points has actually been set.
static bool is_debugging_active() {
#ifdef ENABLE_DEBUGGER_SUPPORT
Isolate* isolate = Isolate::Current();
return V8::UseCrankshaft() ?
isolate->debug()->has_break_points() :
isolate->debugger()->IsDebuggerActive();
#else
return false;
#endif
}
static bool AlwaysFullCompiler() {
return FLAG_always_full_compiler || is_debugging_active();
}
static void FinishOptimization(Handle<JSFunction> function, int64_t start) {
int opt_count = function->shared()->opt_count();
function->shared()->set_opt_count(opt_count + 1);
double ms = static_cast<double>(OS::Ticks() - start) / 1000;
if (FLAG_trace_opt) {
PrintF("[optimizing: ");
function->PrintName();
PrintF(" / %" V8PRIxPTR, reinterpret_cast<intptr_t>(*function));
PrintF(" - took %0.3f ms]\n", ms);
}
if (FLAG_trace_opt_stats) {
static double compilation_time = 0.0;
static int compiled_functions = 0;
static int code_size = 0;
compilation_time += ms;
compiled_functions++;
code_size += function->shared()->SourceSize();
PrintF("Compiled: %d functions with %d byte source size in %fms.\n",
compiled_functions,
code_size,
compilation_time);
}
}
static bool MakeCrankshaftCode(CompilationInfo* info) {
// Test if we can optimize this function when asked to. We can only
// do this after the scopes are computed.
if (!V8::UseCrankshaft()) {
info->DisableOptimization();
}
// In case we are not optimizing simply return the code from
// the full code generator.
if (!info->IsOptimizing()) {
return FullCodeGenerator::MakeCode(info);
}
// We should never arrive here if there is not code object on the
// shared function object.
Handle<Code> code(info->shared_info()->code());
ASSERT(code->kind() == Code::FUNCTION);
// We should never arrive here if optimization has been disabled on the
// shared function info.
ASSERT(!info->shared_info()->optimization_disabled());
// Fall back to using the full code generator if it's not possible
// to use the Hydrogen-based optimizing compiler. We already have
// generated code for this from the shared function object.
if (AlwaysFullCompiler()) {
info->SetCode(code);
return true;
}
// Limit the number of times we re-compile a functions with
// the optimizing compiler.
const int kMaxOptCount =
FLAG_deopt_every_n_times == 0 ? Compiler::kDefaultMaxOptCount : 1000;
if (info->shared_info()->opt_count() > kMaxOptCount) {
info->AbortOptimization();
info->shared_info()->DisableOptimization();
// True indicates the compilation pipeline is still going, not
// necessarily that we optimized the code.
return true;
}
// Due to an encoding limit on LUnallocated operands in the Lithium
// language, we cannot optimize functions with too many formal parameters
// or perform on-stack replacement for function with too many
// stack-allocated local variables.
//
// The encoding is as a signed value, with parameters and receiver using
// the negative indices and locals the non-negative ones.
const int parameter_limit = -LUnallocated::kMinFixedIndex;
const int locals_limit = LUnallocated::kMaxFixedIndex;
Scope* scope = info->scope();
if ((scope->num_parameters() + 1) > parameter_limit ||
(info->osr_ast_id() != AstNode::kNoNumber &&
scope->num_parameters() + 1 + scope->num_stack_slots() > locals_limit)) {
info->AbortOptimization();
info->shared_info()->DisableOptimization();
// True indicates the compilation pipeline is still going, not
// necessarily that we optimized the code.
return true;
}
// Take --hydrogen-filter into account.
Handle<String> name = info->function()->debug_name();
if (*FLAG_hydrogen_filter != '\0') {
Vector<const char> filter = CStrVector(FLAG_hydrogen_filter);
if ((filter[0] == '-'
&& name->IsEqualTo(filter.SubVector(1, filter.length())))
|| (filter[0] != '-' && !name->IsEqualTo(filter))) {
info->SetCode(code);
return true;
}
}
// Recompile the unoptimized version of the code if the current version
// doesn't have deoptimization support. Alternatively, we may decide to
// run the full code generator to get a baseline for the compile-time
// performance of the hydrogen-based compiler.
int64_t start = OS::Ticks();
bool should_recompile = !info->shared_info()->has_deoptimization_support();
if (should_recompile || FLAG_hydrogen_stats) {
HPhase phase(HPhase::kFullCodeGen);
CompilationInfo unoptimized(info->shared_info());
// Note that we use the same AST that we will use for generating the
// optimized code.
unoptimized.SetFunction(info->function());
unoptimized.SetScope(info->scope());
if (should_recompile) unoptimized.EnableDeoptimizationSupport();
bool succeeded = FullCodeGenerator::MakeCode(&unoptimized);
if (should_recompile) {
if (!succeeded) return false;
Handle<SharedFunctionInfo> shared = info->shared_info();
shared->EnableDeoptimizationSupport(*unoptimized.code());
// The existing unoptimized code was replaced with the new one.
Compiler::RecordFunctionCompilation(
Logger::LAZY_COMPILE_TAG, &unoptimized, shared);
}
}
// Check that the unoptimized, shared code is ready for
// optimizations. When using the always_opt flag we disregard the
// optimizable marker in the code object and optimize anyway. This
// is safe as long as the unoptimized code has deoptimization
// support.
ASSERT(FLAG_always_opt || code->optimizable());
ASSERT(info->shared_info()->has_deoptimization_support());
if (FLAG_trace_hydrogen) {
PrintF("-----------------------------------------------------------\n");
PrintF("Compiling method %s using hydrogen\n", *name->ToCString());
HTracer::Instance()->TraceCompilation(info->function());
}
Handle<Context> global_context(info->closure()->context()->global_context());
TypeFeedbackOracle oracle(code, global_context, info->isolate());
HGraphBuilder builder(info, &oracle);
HPhase phase(HPhase::kTotal);
HGraph* graph = builder.CreateGraph();
if (info->isolate()->has_pending_exception()) {
info->SetCode(Handle<Code>::null());
return false;
}
if (graph != NULL) {
Handle<Code> optimized_code = graph->Compile(info);
if (!optimized_code.is_null()) {
info->SetCode(optimized_code);
FinishOptimization(info->closure(), start);
return true;
}
}
// Keep using the shared code.
info->AbortOptimization();
if (!builder.inline_bailout()) {
// Mark the shared code as unoptimizable unless it was an inlined
// function that bailed out.
info->shared_info()->DisableOptimization();
}
// True indicates the compilation pipeline is still going, not necessarily
// that we optimized the code.
return true;
}
static bool GenerateCode(CompilationInfo* info) {
return info->IsCompilingForDebugging() || !V8::UseCrankshaft() ?
FullCodeGenerator::MakeCode(info) :
MakeCrankshaftCode(info);
}
static bool MakeCode(CompilationInfo* info) {
// Precondition: code has been parsed. Postcondition: the code field in
// the compilation info is set if compilation succeeded.
ASSERT(info->function() != NULL);
return Rewriter::Rewrite(info) && Scope::Analyze(info) && GenerateCode(info);
}
#ifdef ENABLE_DEBUGGER_SUPPORT
bool Compiler::MakeCodeForLiveEdit(CompilationInfo* info) {
// Precondition: code has been parsed. Postcondition: the code field in
// the compilation info is set if compilation succeeded.
bool succeeded = MakeCode(info);
if (!info->shared_info().is_null()) {
Handle<ScopeInfo> scope_info = ScopeInfo::Create(info->scope());
info->shared_info()->set_scope_info(*scope_info);
}
return succeeded;
}
#endif
static Handle<SharedFunctionInfo> MakeFunctionInfo(CompilationInfo* info) {
Isolate* isolate = info->isolate();
ZoneScope zone_scope(isolate, DELETE_ON_EXIT);
PostponeInterruptsScope postpone(isolate);
ASSERT(!isolate->global_context().is_null());
Handle<Script> script = info->script();
script->set_context_data((*isolate->global_context())->data());
#ifdef ENABLE_DEBUGGER_SUPPORT
if (info->is_eval()) {
Script::CompilationType compilation_type = Script::COMPILATION_TYPE_EVAL;
script->set_compilation_type(Smi::FromInt(compilation_type));
// For eval scripts add information on the function from which eval was
// called.
if (info->is_eval()) {
StackTraceFrameIterator it(isolate);
if (!it.done()) {
script->set_eval_from_shared(
JSFunction::cast(it.frame()->function())->shared());
Code* code = it.frame()->LookupCode();
int offset = static_cast<int>(
it.frame()->pc() - code->instruction_start());
script->set_eval_from_instructions_offset(Smi::FromInt(offset));
}
}
}
// Notify debugger
isolate->debugger()->OnBeforeCompile(script);
#endif
// Only allow non-global compiles for eval.
ASSERT(info->is_eval() || info->is_global());
ParsingFlags flags = kNoParsingFlags;
if (info->pre_parse_data() != NULL ||
String::cast(script->source())->length() > FLAG_min_preparse_length) {
flags = kAllowLazy;
}
if (!ParserApi::Parse(info, flags)) {
return Handle<SharedFunctionInfo>::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 = info->is_eval()
? info->isolate()->counters()->compile_eval()
: info->isolate()->counters()->compile();
HistogramTimerScope timer(rate);
// Compile the code.
FunctionLiteral* lit = info->function();
LiveEditFunctionTracker live_edit_tracker(isolate, lit);
if (!MakeCode(info)) {
if (!isolate->has_pending_exception()) isolate->StackOverflow();
return Handle<SharedFunctionInfo>::null();
}
// Allocate function.
ASSERT(!info->code().is_null());
Handle<SharedFunctionInfo> result =
isolate->factory()->NewSharedFunctionInfo(
lit->name(),
lit->materialized_literal_count(),
info->code(),
ScopeInfo::Create(info->scope()));
ASSERT_EQ(RelocInfo::kNoPosition, lit->function_token_position());
Compiler::SetFunctionInfo(result, lit, true, script);
if (script->name()->IsString()) {
PROFILE(isolate, CodeCreateEvent(
info->is_eval()
? Logger::EVAL_TAG
: Logger::ToNativeByScript(Logger::SCRIPT_TAG, *script),
*info->code(),
*result,
String::cast(script->name())));
GDBJIT(AddCode(Handle<String>(String::cast(script->name())),
script,
info->code(),
info));
} else {
PROFILE(isolate, CodeCreateEvent(
info->is_eval()
? Logger::EVAL_TAG
: Logger::ToNativeByScript(Logger::SCRIPT_TAG, *script),
*info->code(),
*result,
isolate->heap()->empty_string()));
GDBJIT(AddCode(Handle<String>(), script, info->code(), info));
}
// 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(result, lit->expected_property_count());
script->set_compilation_state(
Smi::FromInt(Script::COMPILATION_STATE_COMPILED));
#ifdef ENABLE_DEBUGGER_SUPPORT
// Notify debugger
isolate->debugger()->OnAfterCompile(
script, Debugger::NO_AFTER_COMPILE_FLAGS);
#endif
live_edit_tracker.RecordFunctionInfo(result, lit);
return result;
}
Handle<SharedFunctionInfo> Compiler::Compile(Handle<String> source,
Handle<Object> script_name,
int line_offset,
int column_offset,
v8::Extension* extension,
ScriptDataImpl* pre_data,
Handle<Object> script_data,
NativesFlag natives) {
Isolate* isolate = source->GetIsolate();
int source_length = source->length();
isolate->counters()->total_load_size()->Increment(source_length);
isolate->counters()->total_compile_size()->Increment(source_length);
// The VM is in the COMPILER state until exiting this function.
VMState state(isolate, COMPILER);
CompilationCache* compilation_cache = isolate->compilation_cache();
// Do a lookup in the compilation cache but not for extensions.
Handle<SharedFunctionInfo> result;
if (extension == NULL) {
result = compilation_cache->LookupScript(source,
script_name,
line_offset,
column_offset);
}
if (result.is_null()) {
// No cache entry found. Do pre-parsing, if it makes sense, and compile
// the script.
// Building preparse data that is only used immediately after is only a
// saving if we might skip building the AST for lazily compiled functions.
// I.e., preparse data isn't relevant when the lazy flag is off, and
// for small sources, odds are that there aren't many functions
// that would be compiled lazily anyway, so we skip the preparse step
// in that case too.
// Create a script object describing the script to be compiled.
Handle<Script> script = FACTORY->NewScript(source);
if (natives == NATIVES_CODE) {
script->set_type(Smi::FromInt(Script::TYPE_NATIVE));
}
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));
}
script->set_data(script_data.is_null() ? HEAP->undefined_value()
: *script_data);
// Compile the function and add it to the cache.
CompilationInfo info(script);
info.MarkAsGlobal();
info.SetExtension(extension);
info.SetPreParseData(pre_data);
if (FLAG_use_strict) {
info.SetLanguageMode(FLAG_harmony_scoping ? EXTENDED_MODE : STRICT_MODE);
}
result = MakeFunctionInfo(&info);
if (extension == NULL && !result.is_null()) {
compilation_cache->PutScript(source, result);
}
} else {
if (result->ic_age() != HEAP->global_ic_age()) {
result->ResetForNewContext(HEAP->global_ic_age());
}
}
if (result.is_null()) isolate->ReportPendingMessages();
return result;
}
Handle<SharedFunctionInfo> Compiler::CompileEval(Handle<String> source,
Handle<Context> context,
bool is_global,
LanguageMode language_mode,
int scope_position) {
Isolate* isolate = source->GetIsolate();
int source_length = source->length();
isolate->counters()->total_eval_size()->Increment(source_length);
isolate->counters()->total_compile_size()->Increment(source_length);
// The VM is in the COMPILER state until exiting this function.
VMState state(isolate, COMPILER);
// Do a lookup in the compilation cache; if the entry is not there, invoke
// the compiler and add the result to the cache.
Handle<SharedFunctionInfo> result;
CompilationCache* compilation_cache = isolate->compilation_cache();
result = compilation_cache->LookupEval(source,
context,
is_global,
language_mode,
scope_position);
if (result.is_null()) {
// Create a script object describing the script to be compiled.
Handle<Script> script = isolate->factory()->NewScript(source);
CompilationInfo info(script);
info.MarkAsEval();
if (is_global) info.MarkAsGlobal();
info.SetLanguageMode(language_mode);
info.SetCallingContext(context);
result = MakeFunctionInfo(&info);
if (!result.is_null()) {
// Explicitly disable optimization for eval code. We're not yet prepared
// to handle eval-code in the optimizing compiler.
result->DisableOptimization();
// If caller is strict mode, the result must be in strict mode or
// extended mode as well, but not the other way around. Consider:
// eval("'use strict'; ...");
ASSERT(language_mode != STRICT_MODE || !result->is_classic_mode());
// If caller is in extended mode, the result must also be in
// extended mode.
ASSERT(language_mode != EXTENDED_MODE ||
result->is_extended_mode());
compilation_cache->PutEval(
source, context, is_global, result, scope_position);
}
} else {
if (result->ic_age() != HEAP->global_ic_age()) {
result->ResetForNewContext(HEAP->global_ic_age());
}
}
return result;
}
bool Compiler::CompileLazy(CompilationInfo* info) {
Isolate* isolate = info->isolate();
ZoneScope zone_scope(isolate, DELETE_ON_EXIT);
// The VM is in the COMPILER state until exiting this function.
VMState state(isolate, COMPILER);
PostponeInterruptsScope postpone(isolate);
Handle<SharedFunctionInfo> shared = info->shared_info();
int compiled_size = shared->end_position() - shared->start_position();
isolate->counters()->total_compile_size()->Increment(compiled_size);
// Generate the AST for the lazily compiled function.
if (ParserApi::Parse(info, kNoParsingFlags)) {
// 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(isolate->counters()->compile_lazy());
// After parsing we know the function's language mode. Remember it.
LanguageMode language_mode = info->function()->language_mode();
info->SetLanguageMode(language_mode);
shared->set_language_mode(language_mode);
// Compile the code.
if (!MakeCode(info)) {
if (!isolate->has_pending_exception()) {
isolate->StackOverflow();
}
} else {
ASSERT(!info->code().is_null());
Handle<Code> code = info->code();
// Set optimizable to false if this is disallowed by the shared
// function info, e.g., we might have flushed the code and must
// reset this bit when lazy compiling the code again.
if (shared->optimization_disabled()) code->set_optimizable(false);
Handle<JSFunction> function = info->closure();
RecordFunctionCompilation(Logger::LAZY_COMPILE_TAG, info, shared);
if (info->IsOptimizing()) {
ASSERT(shared->scope_info() != ScopeInfo::Empty());
function->ReplaceCode(*code);
} else {
// Update the shared function info with the compiled code and the
// scope info. Please note, that the order of the shared function
// info initialization is important since set_scope_info might
// trigger a GC, causing the ASSERT below to be invalid if the code
// was flushed. By setting the code object last we avoid this.
Handle<ScopeInfo> scope_info = ScopeInfo::Create(info->scope());
shared->set_scope_info(*scope_info);
shared->set_code(*code);
if (!function.is_null()) {
function->ReplaceCode(*code);
ASSERT(!function->IsOptimized());
}
// Set the expected number of properties for instances.
FunctionLiteral* lit = info->function();
int expected = lit->expected_property_count();
SetExpectedNofPropertiesFromEstimate(shared, expected);
// Set the optimization hints after performing lazy compilation, as
// these are not set when the function is set up as a lazily
// compiled function.
shared->SetThisPropertyAssignmentsInfo(
lit->has_only_simple_this_property_assignments(),
*lit->this_property_assignments());
// Check the function has compiled code.
ASSERT(shared->is_compiled());
shared->set_code_age(0);
shared->set_dont_optimize(lit->flags()->Contains(kDontOptimize));
shared->set_dont_inline(lit->flags()->Contains(kDontInline));
shared->set_ast_node_count(lit->ast_node_count());
if (V8::UseCrankshaft()&&
!function.is_null() &&
!shared->optimization_disabled()) {
// If we're asked to always optimize, we compile the optimized
// version of the function right away - unless the debugger is
// active as it makes no sense to compile optimized code then.
if (FLAG_always_opt &&
!Isolate::Current()->DebuggerHasBreakPoints()) {
CompilationInfo optimized(function);
optimized.SetOptimizing(AstNode::kNoNumber);
return CompileLazy(&optimized);
}
}
}
return true;
}
}
ASSERT(info->code().is_null());
return false;
}
Handle<SharedFunctionInfo> Compiler::BuildFunctionInfo(FunctionLiteral* literal,
Handle<Script> script) {
// Precondition: code has been parsed and scopes have been analyzed.
CompilationInfo info(script);
info.SetFunction(literal);
info.SetScope(literal->scope());
info.SetLanguageMode(literal->scope()->language_mode());
LiveEditFunctionTracker live_edit_tracker(info.isolate(), literal);
// Determine if the function can be lazily compiled. This is necessary to
// allow some of our builtin JS files to be lazily compiled. These
// builtins cannot be handled lazily by the parser, since we have to know
// if a function uses the special natives syntax, which is something the
// parser records.
bool allow_lazy = literal->AllowsLazyCompilation() &&
!LiveEditFunctionTracker::IsActive(info.isolate());
Handle<ScopeInfo> scope_info(ScopeInfo::Empty());
// Generate code
if (FLAG_lazy && allow_lazy) {
Handle<Code> code = info.isolate()->builtins()->LazyCompile();
info.SetCode(code);
} else if ((V8::UseCrankshaft() && MakeCrankshaftCode(&info)) ||
(!V8::UseCrankshaft() && FullCodeGenerator::MakeCode(&info))) {
ASSERT(!info.code().is_null());
scope_info = ScopeInfo::Create(info.scope());
} else {
return Handle<SharedFunctionInfo>::null();
}
// Create a shared function info object.
Handle<SharedFunctionInfo> result =
FACTORY->NewSharedFunctionInfo(literal->name(),
literal->materialized_literal_count(),
info.code(),
scope_info);
SetFunctionInfo(result, literal, false, script);
RecordFunctionCompilation(Logger::FUNCTION_TAG, &info, result);
result->set_allows_lazy_compilation(allow_lazy);
// Set the expected number of properties for instances and return
// the resulting function.
SetExpectedNofPropertiesFromEstimate(result,
literal->expected_property_count());
live_edit_tracker.RecordFunctionInfo(result, literal);
return result;
}
// Sets the function info on a function.
// The start_position points to the first '(' character after the function name
// in the full script source. When counting characters in the script source the
// the first character is number 0 (not 1).
void Compiler::SetFunctionInfo(Handle<SharedFunctionInfo> function_info,
FunctionLiteral* lit,
bool is_toplevel,
Handle<Script> script) {
function_info->set_length(lit->parameter_count());
function_info->set_formal_parameter_count(lit->parameter_count());
function_info->set_script(*script);
function_info->set_function_token_position(lit->function_token_position());
function_info->set_start_position(lit->start_position());
function_info->set_end_position(lit->end_position());
function_info->set_is_expression(lit->is_expression());
function_info->set_is_anonymous(lit->is_anonymous());
function_info->set_is_toplevel(is_toplevel);
function_info->set_inferred_name(*lit->inferred_name());
function_info->SetThisPropertyAssignmentsInfo(
lit->has_only_simple_this_property_assignments(),
*lit->this_property_assignments());
function_info->set_allows_lazy_compilation(lit->AllowsLazyCompilation());
function_info->set_language_mode(lit->language_mode());
function_info->set_uses_arguments(lit->scope()->arguments() != NULL);
function_info->set_has_duplicate_parameters(lit->has_duplicate_parameters());
function_info->set_ast_node_count(lit->ast_node_count());
function_info->set_is_function(lit->is_function());
function_info->set_dont_optimize(lit->flags()->Contains(kDontOptimize));
function_info->set_dont_inline(lit->flags()->Contains(kDontInline));
}
void Compiler::RecordFunctionCompilation(Logger::LogEventsAndTags tag,
CompilationInfo* info,
Handle<SharedFunctionInfo> shared) {
// SharedFunctionInfo is passed separately, because if CompilationInfo
// was created using Script object, it will not have it.
// Log the code generation. If source information is available include
// script name and line number. Check explicitly whether logging is
// enabled as finding the line number is not free.
if (info->isolate()->logger()->is_logging() ||
CpuProfiler::is_profiling(info->isolate())) {
Handle<Script> script = info->script();
Handle<Code> code = info->code();
if (*code == info->isolate()->builtins()->builtin(Builtins::kLazyCompile))
return;
if (script->name()->IsString()) {
int line_num = GetScriptLineNumber(script, shared->start_position()) + 1;
USE(line_num);
PROFILE(info->isolate(),
CodeCreateEvent(Logger::ToNativeByScript(tag, *script),
*code,
*shared,
String::cast(script->name()),
line_num));
} else {
PROFILE(info->isolate(),
CodeCreateEvent(Logger::ToNativeByScript(tag, *script),
*code,
*shared,
shared->DebugName()));
}
}
GDBJIT(AddCode(Handle<String>(shared->DebugName()),
Handle<Script>(info->script()),
Handle<Code>(info->code()),
info));
}
} } // namespace v8::internal