src/parser.cc - Issue 5545006: Optimized scanner to avoid virtual calls for every character read.

Unified Diff: src/parser.cc

Issue 5545006: Optimized scanner to avoid virtual calls for every character read. (Closed)

Patch Set: Created 10 years ago

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Index: src/parser.cc

diff --git a/src/parser.cc b/src/parser.cc

index db36297a5d488aad8bb7726487158604d0d9d039..2bff621583c2f288afc51b0ee78355278575f8e7 100644

--- a/src/parser.cc

+++ b/src/parser.cc

@@ -608,7 +608,22 @@ FunctionLiteral* Parser::ParseProgram(Handle<String> source,

// Initialize parser state.

source->TryFlatten();

- scanner_.Initialize(source);

+ if (source->IsExternalTwoByteString()) {

+ ExternalTwoByteStringUC16CharacterStream stream(

+ Handle<ExternalTwoByteString>::cast(source), 0, source->length());

+ scanner_.Initialize(&stream, JavaScriptScanner::kAllLiterals);

+ return DoParseProgram(source, in_global_context, &zone_scope);

Erik Corry 2010/12/07 12:27:30 This last line is common between both branches and

Lasse Reichstein 2010/12/07 14:05:54 The current code is mandated by the destructor of

+ } else {

+ GenericStringUC16CharacterStream stream(source, 0, source->length());

+ scanner_.Initialize(&stream, JavaScriptScanner::kAllLiterals);

+ return DoParseProgram(source, in_global_context, &zone_scope);

+ }

+FunctionLiteral* Parser::DoParseProgram(Handle<String> source,

+ bool in_global_context,

+ ZoneScope* zone_scope) {

ASSERT(target_stack_ == NULL);

if (pre_data_ != NULL) pre_data_->Initialize();

@@ -654,25 +669,44 @@ FunctionLiteral* Parser::ParseProgram(Handle<String> source,

// If there was a syntax error we have to get rid of the AST

// and it is not safe to do so before the scope has been deleted.

- if (result == NULL) zone_scope.DeleteOnExit();

+ if (result == NULL) zone_scope->DeleteOnExit();

return result;

}

FunctionLiteral* Parser::ParseLazy(Handle<SharedFunctionInfo> info) {

CompilationZoneScope zone_scope(DONT_DELETE_ON_EXIT);

HistogramTimerScope timer(&Counters::parse_lazy);

Handle<String> source(String::cast(script_->source()));

Counters::total_parse_size.Increment(source->length());

+ // Initialize parser state.

+ source->TryFlatten();

+ if (source->IsExternalTwoByteString()) {

+ ExternalTwoByteStringUC16CharacterStream stream(

+ Handle<ExternalTwoByteString>::cast(source),

+ info->start_position(),

+ info->end_position());

+ FunctionLiteral* result = ParseLazy(info, &stream, &zone_scope);

+ return result;

+ } else {

+ GenericStringUC16CharacterStream stream(source,

+ info->start_position(),

+ info->end_position());

+ FunctionLiteral* result = ParseLazy(info, &stream, &zone_scope);

+ return result;

+ }

Erik Corry 2010/12/07 12:27:30 Missing blank line

+FunctionLiteral* Parser::ParseLazy(Handle<SharedFunctionInfo> info,

+ UC16CharacterStream* source,

+ ZoneScope* zone_scope) {

+ scanner_.Initialize(source, JavaScriptScanner::kAllLiterals);

+ ASSERT(target_stack_ == NULL);

Handle<String> name(String::cast(info->name()));

fni_ = new FuncNameInferrer();

fni_->PushEnclosingName(name);

- // Initialize parser state.

- source->TryFlatten();

- scanner_.Initialize(source, info->start_position(), info->end_position());

- ASSERT(target_stack_ == NULL);

mode_ = PARSE_EAGERLY;

// Place holder for the result.

@@ -704,7 +738,7 @@ FunctionLiteral* Parser::ParseLazy(Handle<SharedFunctionInfo> info) {

// not safe to do before scope has been deleted.

if (result == NULL) {

Top::StackOverflow();

- zone_scope.DeleteOnExit();

+ zone_scope->DeleteOnExit();

}

return result;

}

@@ -715,12 +749,12 @@ Handle<String> Parser::GetSymbol(bool* ok) {

if (pre_data() != NULL) {

symbol_id = pre_data()->GetSymbolIdentifier();

}

- return LookupSymbol(symbol_id, scanner_.literal());

+ return LookupSymbol(symbol_id, scanner().literal());

}

void Parser::ReportMessage(const char* type, Vector<const char*> args) {

- Scanner::Location source_location = scanner_.location();

+ Scanner::Location source_location = scanner().location();

ReportMessageAt(source_location, type, args);

}

@@ -1637,7 +1671,7 @@ Statement* Parser::ParseContinueStatement(bool* ok) {

Expect(Token::CONTINUE, CHECK_OK);

Handle<String> label = Handle<String>::null();

Token::Value tok = peek();

- if (!scanner_.has_line_terminator_before_next() &&

+ if (!scanner().has_line_terminator_before_next() &&

tok != Token::SEMICOLON && tok != Token::RBRACE && tok != Token::EOS) {

label = ParseIdentifier(CHECK_OK);

}

@@ -1663,7 +1697,7 @@ Statement* Parser::ParseBreakStatement(ZoneStringList* labels, bool* ok) {

Expect(Token::BREAK, CHECK_OK);

Handle<String> label;

Token::Value tok = peek();

- if (!scanner_.has_line_terminator_before_next() &&

+ if (!scanner().has_line_terminator_before_next() &&

tok != Token::SEMICOLON && tok != Token::RBRACE && tok != Token::EOS) {

label = ParseIdentifier(CHECK_OK);

}

@@ -1708,7 +1742,7 @@ Statement* Parser::ParseReturnStatement(bool* ok) {

}

Token::Value tok = peek();

- if (scanner_.has_line_terminator_before_next() ||

+ if (scanner().has_line_terminator_before_next() ||

tok == Token::SEMICOLON ||

tok == Token::RBRACE ||

tok == Token::EOS) {

@@ -1840,7 +1874,7 @@ Statement* Parser::ParseThrowStatement(bool* ok) {

Expect(Token::THROW, CHECK_OK);

int pos = scanner().location().beg_pos;

- if (scanner_.has_line_terminator_before_next()) {

+ if (scanner().has_line_terminator_before_next()) {

ReportMessage("newline_after_throw", Vector<const char*>::empty());

*ok = false;

return NULL;

@@ -2401,7 +2435,8 @@ Expression* Parser::ParsePostfixExpression(bool* ok) {

// LeftHandSideExpression ('++' | '--')?

Expression* expression = ParseLeftHandSideExpression(CHECK_OK);

- if (!scanner_.has_line_terminator_before_next() && Token::IsCountOp(peek())) {

+ if (!scanner().has_line_terminator_before_next()

+ && Token::IsCountOp(peek())) {

Erik Corry 2010/12/07 12:27:30 Everywhere else in this file seems to have the &&

Lasse Reichstein 2010/12/07 14:05:54 I prefer having them on the second line, but let's

Vitaly Repeshko 2010/12/07 14:15:50 Please don't :) While http://google-styleguide.go

// Signal a reference error if the expression is an invalid

// left-hand side expression. We could report this as a syntax

// error here but for compatibility with JSC we choose to report the

@@ -2670,7 +2705,7 @@ Expression* Parser::ParsePrimaryExpression(bool* ok) {

case Token::NUMBER: {

Consume(Token::NUMBER);

double value =

- StringToDouble(scanner_.literal(), ALLOW_HEX | ALLOW_OCTALS);

+ StringToDouble(scanner().literal(), ALLOW_HEX | ALLOW_OCTALS);

result = NewNumberLiteral(value);

break;

}

@@ -3020,7 +3055,7 @@ Expression* Parser::ParseObjectLiteral(bool* ok) {

case Token::NUMBER: {

Consume(Token::NUMBER);

double value =

- StringToDouble(scanner_.literal(), ALLOW_HEX | ALLOW_OCTALS);

+ StringToDouble(scanner().literal(), ALLOW_HEX | ALLOW_OCTALS);

key = NewNumberLiteral(value);

break;

}

@@ -3081,7 +3116,7 @@ Expression* Parser::ParseObjectLiteral(bool* ok) {

Expression* Parser::ParseRegExpLiteral(bool seen_equal, bool* ok) {

- if (!scanner_.ScanRegExpPattern(seen_equal)) {

+ if (!scanner().ScanRegExpPattern(seen_equal)) {

Next();

ReportMessage("unterminated_regexp", Vector<const char*>::empty());

*ok = false;

@@ -3091,10 +3126,10 @@ Expression* Parser::ParseRegExpLiteral(bool seen_equal, bool* ok) {

int literal_index = temp_scope_->NextMaterializedLiteralIndex();

Handle<String> js_pattern =

- Factory::NewStringFromUtf8(scanner_.next_literal(), TENURED);

- scanner_.ScanRegExpFlags();

+ Factory::NewStringFromUtf8(scanner().next_literal(), TENURED);

+ scanner().ScanRegExpFlags();

Handle<String> js_flags =

- Factory::NewStringFromUtf8(scanner_.next_literal(), TENURED);

+ Factory::NewStringFromUtf8(scanner().next_literal(), TENURED);

Next();

return new RegExpLiteral(js_pattern, js_flags, literal_index);

@@ -3150,7 +3185,7 @@ FunctionLiteral* Parser::ParseFunctionLiteral(Handle<String> var_name,

// FormalParameterList ::

// '(' (Identifier)*[','] ')'

Expect(Token::LPAREN, CHECK_OK);

- int start_pos = scanner_.location().beg_pos;

+ int start_pos = scanner().location().beg_pos;

bool done = (peek() == Token::RPAREN);

while (!done) {

Handle<String> param_name = ParseIdentifier(CHECK_OK);

@@ -3187,7 +3222,7 @@ FunctionLiteral* Parser::ParseFunctionLiteral(Handle<String> var_name,

bool is_lazily_compiled =

mode() == PARSE_LAZILY && top_scope_->HasTrivialOuterContext();

- int function_block_pos = scanner_.location().beg_pos;

+ int function_block_pos = scanner().location().beg_pos;

int materialized_literal_count;

int expected_property_count;

int end_pos;

@@ -3204,7 +3239,8 @@ FunctionLiteral* Parser::ParseFunctionLiteral(Handle<String> var_name,

ReportInvalidPreparseData(name, CHECK_OK);

}

Counters::total_preparse_skipped.Increment(end_pos - function_block_pos);

- scanner_.SeekForward(end_pos);

+ // Seek to position just before terminal '}'.

+ scanner().SeekForward(end_pos - 1);

materialized_literal_count = entry.literal_count();

expected_property_count = entry.property_count();

only_simple_this_property_assignments = false;

@@ -3220,7 +3256,7 @@ FunctionLiteral* Parser::ParseFunctionLiteral(Handle<String> var_name,

this_property_assignments = temp_scope.this_property_assignments();

Expect(Token::RBRACE, CHECK_OK);

- end_pos = scanner_.location().end_pos;

+ end_pos = scanner().location().end_pos;

}

FunctionLiteral* function_literal =

@@ -3324,7 +3360,7 @@ void Parser::ExpectSemicolon(bool* ok) {

Next();

return;

}

- if (scanner_.has_line_terminator_before_next() ||

+ if (scanner().has_line_terminator_before_next() ||

tok == Token::RBRACE ||

tok == Token::EOS) {

return;

@@ -3375,8 +3411,8 @@ Handle<String> Parser::ParseIdentifierOrGetOrSet(bool* is_get,

bool* ok) {

Expect(Token::IDENTIFIER, ok);

if (!*ok) return Handle<String>();

- if (scanner_.literal_length() == 3) {

- const char* token = scanner_.literal_string();

+ if (scanner().literal_length() == 3) {

+ const char* token = scanner().literal_string();

*is_get = strcmp(token, "get") == 0;

*is_set = !*is_get && strcmp(token, "set") == 0;

}

@@ -3495,8 +3531,8 @@ Expression* Parser::NewThrowError(Handle<String> constructor,

// ----------------------------------------------------------------------------

// JSON

-Handle<Object> JsonParser::ParseJson(Handle<String> source) {

- source->TryFlatten();

+Handle<Object> JsonParser::ParseJson(Handle<String> script,

+ UC16CharacterStream* source) {

scanner_.Initialize(source);

stack_overflow_ = false;

Handle<Object> result = ParseJsonValue();

@@ -3532,7 +3568,7 @@ Handle<Object> JsonParser::ParseJson(Handle<String> source) {

}

Scanner::Location source_location = scanner_.location();

- MessageLocation location(Factory::NewScript(source),

+ MessageLocation location(Factory::NewScript(script),

source_location.beg_pos,

source_location.end_pos);

int argc = (name_opt == NULL) ? 0 : 1;

@@ -4547,13 +4583,12 @@ int ScriptDataImpl::ReadNumber(byte** source) {

// Create a Scanner for the preparser to use as input, and preparse the source.

-static ScriptDataImpl* DoPreParse(Handle<String> source,

- unibrow::CharacterStream* stream,

+static ScriptDataImpl* DoPreParse(UC16CharacterStream* source,

bool allow_lazy,

ParserRecorder* recorder,

int literal_flags) {

V8JavaScriptScanner scanner;

- scanner.Initialize(source, stream, literal_flags);

+ scanner.Initialize(source, literal_flags);

intptr_t stack_limit = StackGuard::real_climit();

if (!preparser::PreParser::PreParseProgram(&scanner,

recorder,

@@ -4572,8 +4607,7 @@ static ScriptDataImpl* DoPreParse(Handle<String> source,

// Preparse, but only collect data that is immediately useful,

// even if the preparser data is only used once.

-ScriptDataImpl* ParserApi::PartialPreParse(Handle<String> source,

- unibrow::CharacterStream* stream,

+ScriptDataImpl* ParserApi::PartialPreParse(UC16CharacterStream* source,

v8::Extension* extension) {

bool allow_lazy = FLAG_lazy && (extension == NULL);

if (!allow_lazy) {

@@ -4582,22 +4616,19 @@ ScriptDataImpl* ParserApi::PartialPreParse(Handle<String> source,

return NULL;

}

PartialParserRecorder recorder;

- return DoPreParse(source, stream, allow_lazy, &recorder,

+ return DoPreParse(source, allow_lazy, &recorder,

JavaScriptScanner::kNoLiterals);

}

-ScriptDataImpl* ParserApi::PreParse(Handle<String> source,

- unibrow::CharacterStream* stream,

+ScriptDataImpl* ParserApi::PreParse(UC16CharacterStream* source,

v8::Extension* extension) {

Handle<Script> no_script;

bool allow_lazy = FLAG_lazy && (extension == NULL);

CompleteParserRecorder recorder;

int kPreParseLiteralsFlags =

JavaScriptScanner::kLiteralString | JavaScriptScanner::kLiteralIdentifier;

- return DoPreParse(source, stream, allow_lazy,

- &recorder, kPreParseLiteralsFlags);

+ return DoPreParse(source, allow_lazy, &recorder, kPreParseLiteralsFlags);

}

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