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+// Copyright 2010 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 "../include/v8stdint.h"
+#include "unicode.h"
+#include "globals.h"
+#include "checks.h"
+#include "allocation.h"
+#include "utils.h"
+#include "list.h"
+#include "scanner-base.h"
+#include "preparse-data.h"
+#include "preparser.h"
+
+namespace v8 {
+namespace preparser {
+
+// Preparsing checks a JavaScript program and emits preparse-data that helps
+// a later parsing to be faster.
+// See preparser-data.h for the data.
+
+// The PreParser checks that the syntax follows the grammar for JavaScript,
+// and collects some information about the program along the way.
+// The grammar check is only performed in order to understand the program
+// sufficiently to deduce some information about it, that can be used
+// to speed up later parsing. Finding errors is not the goal of pre-parsing,
+// rather it is to speed up properly written and correct programs.
+// That means that contextual checks (like a label being declared where
+// it is used) are generally omitted.
+
+namespace i = ::v8::internal;
+
+#define CHECK_OK ok); \
+ if (!*ok) return -1; \
+ ((void)0
+#define DUMMY ) // to make indentation work
+#undef DUMMY
+
+
+void PreParser::ReportUnexpectedToken(i::Token::Value token) {
+ // We don't report stack overflows here, to avoid increasing the
+ // stack depth even further. Instead we report it after parsing is
+ // over, in ParseProgram.
+ if (token == i::Token::ILLEGAL && scanner_->stack_overflow()) {
+ return;
+ }
+ i::JavaScriptScanner::Location source_location = scanner_->location();
+
+ // Four of the tokens are treated specially
+ switch (token) {
+ case i::Token::EOS:
+ return ReportMessageAt(source_location.beg_pos, source_location.end_pos,
+ "unexpected_eos", NULL);
+ case i::Token::NUMBER:
+ return ReportMessageAt(source_location.beg_pos, source_location.end_pos,
+ "unexpected_token_number", NULL);
+ case i::Token::STRING:
+ return ReportMessageAt(source_location.beg_pos, source_location.end_pos,
+ "unexpected_token_string", NULL);
+ case i::Token::IDENTIFIER:
+ return ReportMessageAt(source_location.beg_pos, source_location.end_pos,
+ "unexpected_token_identifier", NULL);
+ default:
+ const char* name = i::Token::String(token);
+ ReportMessageAt(source_location.beg_pos, source_location.end_pos,
+ "unexpected_token", name);
+ }
+}
+
+
+SourceElements PreParser::ParseSourceElements(int end_token,
+ bool* ok) {
+ // SourceElements ::
+ // (Statement)* <end_token>
+
+ while (peek() != end_token) {
+ ParseStatement(CHECK_OK);
+ }
+ return kUnknownSourceElements;
+}
+
+
+Statement PreParser::ParseStatement(bool* ok) {
+ // Statement ::
+ // Block
+ // VariableStatement
+ // EmptyStatement
+ // ExpressionStatement
+ // IfStatement
+ // IterationStatement
+ // ContinueStatement
+ // BreakStatement
+ // ReturnStatement
+ // WithStatement
+ // LabelledStatement
+ // SwitchStatement
+ // ThrowStatement
+ // TryStatement
+ // DebuggerStatement
+
+ // Note: Since labels can only be used by 'break' and 'continue'
+ // statements, which themselves are only valid within blocks,
+ // iterations or 'switch' statements (i.e., BreakableStatements),
+ // labels can be simply ignored in all other cases; except for
+ // trivial labeled break statements 'label: break label' which is
+ // parsed into an empty statement.
+
+ // Keep the source position of the statement
+ switch (peek()) {
+ case i::Token::LBRACE:
+ return ParseBlock(ok);
+
+ case i::Token::CONST:
+ case i::Token::VAR:
+ return ParseVariableStatement(ok);
+
+ case i::Token::SEMICOLON:
+ Next();
+ return kUnknownStatement;
+
+ case i::Token::IF:
+ return ParseIfStatement(ok);
+
+ case i::Token::DO:
+ return ParseDoWhileStatement(ok);
+
+ case i::Token::WHILE:
+ return ParseWhileStatement(ok);
+
+ case i::Token::FOR:
+ return ParseForStatement(ok);
+
+ case i::Token::CONTINUE:
+ return ParseContinueStatement(ok);
+
+ case i::Token::BREAK:
+ return ParseBreakStatement(ok);
+
+ case i::Token::RETURN:
+ return ParseReturnStatement(ok);
+
+ case i::Token::WITH:
+ return ParseWithStatement(ok);
+
+ case i::Token::SWITCH:
+ return ParseSwitchStatement(ok);
+
+ case i::Token::THROW:
+ return ParseThrowStatement(ok);
+
+ case i::Token::TRY:
+ return ParseTryStatement(ok);
+
+ case i::Token::FUNCTION:
+ return ParseFunctionDeclaration(ok);
+
+ case i::Token::NATIVE:
+ return ParseNativeDeclaration(ok);
+
+ case i::Token::DEBUGGER:
+ return ParseDebuggerStatement(ok);
+
+ default:
+ return ParseExpressionOrLabelledStatement(ok);
+ }
+}
+
+
+Statement PreParser::ParseFunctionDeclaration(bool* ok) {
+ // FunctionDeclaration ::
+ // 'function' Identifier '(' FormalParameterListopt ')' '{' FunctionBody '}'
+ Expect(i::Token::FUNCTION, CHECK_OK);
+ ParseIdentifier(CHECK_OK);
+ ParseFunctionLiteral(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+// Language extension which is only enabled for source files loaded
+// through the API's extension mechanism. A native function
+// declaration is resolved by looking up the function through a
+// callback provided by the extension.
+Statement PreParser::ParseNativeDeclaration(bool* ok) {
+ Expect(i::Token::NATIVE, CHECK_OK);
+ Expect(i::Token::FUNCTION, CHECK_OK);
+ ParseIdentifier(CHECK_OK);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ bool done = (peek() == i::Token::RPAREN);
+ while (!done) {
+ ParseIdentifier(CHECK_OK);
+ done = (peek() == i::Token::RPAREN);
+ if (!done) {
+ Expect(i::Token::COMMA, CHECK_OK);
+ }
+ }
+ Expect(i::Token::RPAREN, CHECK_OK);
+ Expect(i::Token::SEMICOLON, CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseBlock(bool* ok) {
+ // Block ::
+ // '{' Statement* '}'
+
+ // Note that a Block does not introduce a new execution scope!
+ // (ECMA-262, 3rd, 12.2)
+ //
+ Expect(i::Token::LBRACE, CHECK_OK);
+ while (peek() != i::Token::RBRACE) {
+ ParseStatement(CHECK_OK);
+ }
+ Expect(i::Token::RBRACE, CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseVariableStatement(bool* ok) {
+ // VariableStatement ::
+ // VariableDeclarations ';'
+
+ Statement result = ParseVariableDeclarations(true, NULL, CHECK_OK);
+ ExpectSemicolon(CHECK_OK);
+ return result;
+}
+
+
+// If the variable declaration declares exactly one non-const
+// variable, then *var is set to that variable. In all other cases,
+// *var is untouched; in particular, it is the caller's responsibility
+// to initialize it properly. This mechanism is also used for the parsing
+// of 'for-in' loops.
+Statement PreParser::ParseVariableDeclarations(bool accept_IN,
+ int* num_decl,
+ bool* ok) {
+ // VariableDeclarations ::
+ // ('var' | 'const') (Identifier ('=' AssignmentExpression)?)+[',']
+
+ if (peek() == i::Token::VAR) {
+ Consume(i::Token::VAR);
+ } else if (peek() == i::Token::CONST) {
+ Consume(i::Token::CONST);
+ } else {
+ *ok = false;
+ return 0;
+ }
+
+ // The scope of a variable/const declared anywhere inside a function
+ // is the entire function (ECMA-262, 3rd, 10.1.3, and 12.2). .
+ int nvars = 0; // the number of variables declared
+ do {
+ // Parse variable name.
+ if (nvars > 0) Consume(i::Token::COMMA);
+ ParseIdentifier(CHECK_OK);
+ nvars++;
+ if (peek() == i::Token::ASSIGN) {
+ Expect(i::Token::ASSIGN, CHECK_OK);
+ ParseAssignmentExpression(accept_IN, CHECK_OK);
+ }
+ } while (peek() == i::Token::COMMA);
+
+ if (num_decl != NULL) *num_decl = nvars;
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseExpressionOrLabelledStatement(
+ bool* ok) {
+ // ExpressionStatement | LabelledStatement ::
+ // Expression ';'
+ // Identifier ':' Statement
+
+ Expression expr = ParseExpression(true, CHECK_OK);
+ if (peek() == i::Token::COLON && expr == kIdentifierExpression) {
+ Consume(i::Token::COLON);
+ return ParseStatement(ok);
+ }
+ // Parsed expression statement.
+ ExpectSemicolon(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseIfStatement(bool* ok) {
+ // IfStatement ::
+ // 'if' '(' Expression ')' Statement ('else' Statement)?
+
+ Expect(i::Token::IF, CHECK_OK);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+ ParseStatement(CHECK_OK);
+ if (peek() == i::Token::ELSE) {
+ Next();
+ ParseStatement(CHECK_OK);
+ }
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseContinueStatement(bool* ok) {
+ // ContinueStatement ::
+ // 'continue' [no line terminator] Identifier? ';'
+
+ Expect(i::Token::CONTINUE, CHECK_OK);
+ i::Token::Value tok = peek();
+ if (!scanner_->has_line_terminator_before_next() &&
+ tok != i::Token::SEMICOLON &&
+ tok != i::Token::RBRACE &&
+ tok != i::Token::EOS) {
+ ParseIdentifier(CHECK_OK);
+ }
+ ExpectSemicolon(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseBreakStatement(bool* ok) {
+ // BreakStatement ::
+ // 'break' [no line terminator] Identifier? ';'
+
+ Expect(i::Token::BREAK, CHECK_OK);
+ i::Token::Value tok = peek();
+ if (!scanner_->has_line_terminator_before_next() &&
+ tok != i::Token::SEMICOLON &&
+ tok != i::Token::RBRACE &&
+ tok != i::Token::EOS) {
+ ParseIdentifier(CHECK_OK);
+ }
+ ExpectSemicolon(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseReturnStatement(bool* ok) {
+ // ReturnStatement ::
+ // 'return' [no line terminator] Expression? ';'
+
+ // Consume the return token. It is necessary to do the before
+ // reporting any errors on it, because of the way errors are
+ // reported (underlining).
+ Expect(i::Token::RETURN, CHECK_OK);
+
+ // An ECMAScript program is considered syntactically incorrect if it
+ // contains a return statement that is not within the body of a
+ // function. See ECMA-262, section 12.9, page 67.
+ // This is not handled during preparsing.
+
+ i::Token::Value tok = peek();
+ if (!scanner_->has_line_terminator_before_next() &&
+ tok != i::Token::SEMICOLON &&
+ tok != i::Token::RBRACE &&
+ tok != i::Token::EOS) {
+ ParseExpression(true, CHECK_OK);
+ }
+ ExpectSemicolon(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseWithStatement(bool* ok) {
+ // WithStatement ::
+ // 'with' '(' Expression ')' Statement
+ Expect(i::Token::WITH, CHECK_OK);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+
+ scope_->EnterWith();
+ ParseStatement(CHECK_OK);
+ scope_->LeaveWith();
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseSwitchStatement(bool* ok) {
+ // SwitchStatement ::
+ // 'switch' '(' Expression ')' '{' CaseClause* '}'
+
+ Expect(i::Token::SWITCH, CHECK_OK);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+
+ Expect(i::Token::LBRACE, CHECK_OK);
+ i::Token::Value token = peek();
+ while (token != i::Token::RBRACE) {
+ if (token == i::Token::CASE) {
+ Expect(i::Token::CASE, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::COLON, CHECK_OK);
+ } else if (token == i::Token::DEFAULT) {
+ Expect(i::Token::DEFAULT, CHECK_OK);
+ Expect(i::Token::COLON, CHECK_OK);
+ } else {
+ ParseStatement(CHECK_OK);
+ }
+ token = peek();
+ }
+ Expect(i::Token::RBRACE, CHECK_OK);
+
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseDoWhileStatement(bool* ok) {
+ // DoStatement ::
+ // 'do' Statement 'while' '(' Expression ')' ';'
+
+ Expect(i::Token::DO, CHECK_OK);
+ ParseStatement(CHECK_OK);
+ Expect(i::Token::WHILE, CHECK_OK);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseWhileStatement(bool* ok) {
+ // WhileStatement ::
+ // 'while' '(' Expression ')' Statement
+
+ Expect(i::Token::WHILE, CHECK_OK);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+ ParseStatement(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseForStatement(bool* ok) {
+ // ForStatement ::
+ // 'for' '(' Expression? ';' Expression? ';' Expression? ')' Statement
+
+ Expect(i::Token::FOR, CHECK_OK);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ if (peek() != i::Token::SEMICOLON) {
+ if (peek() == i::Token::VAR || peek() == i::Token::CONST) {
+ int decl_count;
+ ParseVariableDeclarations(false, &decl_count, CHECK_OK);
+ if (peek() == i::Token::IN && decl_count == 1) {
+ Expect(i::Token::IN, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+
+ ParseStatement(CHECK_OK);
+ return kUnknownStatement;
+ }
+ } else {
+ ParseExpression(false, CHECK_OK);
+ if (peek() == i::Token::IN) {
+ Expect(i::Token::IN, CHECK_OK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+
+ ParseStatement(CHECK_OK);
+ return kUnknownStatement;
+ }
+ }
+ }
+
+ // Parsed initializer at this point.
+ Expect(i::Token::SEMICOLON, CHECK_OK);
+
+ if (peek() != i::Token::SEMICOLON) {
+ ParseExpression(true, CHECK_OK);
+ }
+ Expect(i::Token::SEMICOLON, CHECK_OK);
+
+ if (peek() != i::Token::RPAREN) {
+ ParseExpression(true, CHECK_OK);
+ }
+ Expect(i::Token::RPAREN, CHECK_OK);
+
+ ParseStatement(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseThrowStatement(bool* ok) {
+ // ThrowStatement ::
+ // 'throw' [no line terminator] Expression ';'
+
+ Expect(i::Token::THROW, CHECK_OK);
+ if (scanner_->has_line_terminator_before_next()) {
+ i::JavaScriptScanner::Location pos = scanner_->location();
+ ReportMessageAt(pos.beg_pos, pos.end_pos,
+ "newline_after_throw", NULL);
+ *ok = false;
+ return kUnknownStatement;
+ }
+ ParseExpression(true, CHECK_OK);
+ ExpectSemicolon(CHECK_OK);
+
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseTryStatement(bool* ok) {
+ // TryStatement ::
+ // 'try' Block Catch
+ // 'try' Block Finally
+ // 'try' Block Catch Finally
+ //
+ // Catch ::
+ // 'catch' '(' Identifier ')' Block
+ //
+ // Finally ::
+ // 'finally' Block
+
+ // In preparsing, allow any number of catch/finally blocks, including zero
+ // of both.
+
+ Expect(i::Token::TRY, CHECK_OK);
+
+ ParseBlock(CHECK_OK);
+
+ bool catch_or_finally_seen = false;
+ if (peek() == i::Token::CATCH) {
+ Consume(i::Token::CATCH);
+ Expect(i::Token::LPAREN, CHECK_OK);
+ ParseIdentifier(CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+ scope_->EnterWith();
+ ParseBlock(ok);
+ scope_->LeaveWith();
+ if (!*ok) return kUnknownStatement;
+ catch_or_finally_seen = true;
+ }
+ if (peek() == i::Token::FINALLY) {
+ Consume(i::Token::FINALLY);
+ ParseBlock(CHECK_OK);
+ catch_or_finally_seen = true;
+ }
+ if (!catch_or_finally_seen) {
+ *ok = false;
+ }
+ return kUnknownStatement;
+}
+
+
+Statement PreParser::ParseDebuggerStatement(bool* ok) {
+ // In ECMA-262 'debugger' is defined as a reserved keyword. In some browser
+ // contexts this is used as a statement which invokes the debugger as if a
+ // break point is present.
+ // DebuggerStatement ::
+ // 'debugger' ';'
+
+ Expect(i::Token::DEBUGGER, CHECK_OK);
+ ExpectSemicolon(CHECK_OK);
+ return kUnknownStatement;
+}
+
+
+// Precedence = 1
+Expression PreParser::ParseExpression(bool accept_IN, bool* ok) {
+ // Expression ::
+ // AssignmentExpression
+ // Expression ',' AssignmentExpression
+
+ Expression result = ParseAssignmentExpression(accept_IN, CHECK_OK);
+ while (peek() == i::Token::COMMA) {
+ Expect(i::Token::COMMA, CHECK_OK);
+ ParseAssignmentExpression(accept_IN, CHECK_OK);
+ result = kUnknownExpression;
+ }
+ return result;
+}
+
+
+// Precedence = 2
+Expression PreParser::ParseAssignmentExpression(bool accept_IN,
+ bool* ok) {
+ // AssignmentExpression ::
+ // ConditionalExpression
+ // LeftHandSideExpression AssignmentOperator AssignmentExpression
+
+ Expression expression = ParseConditionalExpression(accept_IN, CHECK_OK);
+
+ if (!i::Token::IsAssignmentOp(peek())) {
+ // Parsed conditional expression only (no assignment).
+ return expression;
+ }
+
+ i::Token::Value op = Next(); // Get assignment operator.
+ ParseAssignmentExpression(accept_IN, CHECK_OK);
+
+ if ((op == i::Token::ASSIGN) && (expression == kThisPropertyExpression)) {
+ scope_->AddProperty();
+ }
+
+ return kUnknownExpression;
+}
+
+
+// Precedence = 3
+Expression PreParser::ParseConditionalExpression(bool accept_IN,
+ bool* ok) {
+ // ConditionalExpression ::
+ // LogicalOrExpression
+ // LogicalOrExpression '?' AssignmentExpression ':' AssignmentExpression
+
+ // We start using the binary expression parser for prec >= 4 only!
+ Expression expression = ParseBinaryExpression(4, accept_IN, CHECK_OK);
+ if (peek() != i::Token::CONDITIONAL) return expression;
+ Consume(i::Token::CONDITIONAL);
+ // In parsing the first assignment expression in conditional
+ // expressions we always accept the 'in' keyword; see ECMA-262,
+ // section 11.12, page 58.
+ ParseAssignmentExpression(true, CHECK_OK);
+ Expect(i::Token::COLON, CHECK_OK);
+ ParseAssignmentExpression(accept_IN, CHECK_OK);
+ return kUnknownExpression;
+}
+
+
+int PreParser::Precedence(i::Token::Value tok, bool accept_IN) {
+ if (tok == i::Token::IN && !accept_IN)
+ return 0; // 0 precedence will terminate binary expression parsing
+
+ return i::Token::Precedence(tok);
+}
+
+
+// Precedence >= 4
+Expression PreParser::ParseBinaryExpression(int prec,
+ bool accept_IN,
+ bool* ok) {
+ Expression result = ParseUnaryExpression(CHECK_OK);
+ for (int prec1 = Precedence(peek(), accept_IN); prec1 >= prec; prec1--) {
+ // prec1 >= 4
+ while (Precedence(peek(), accept_IN) == prec1) {
+ Next();
+ ParseBinaryExpression(prec1 + 1, accept_IN, CHECK_OK);
+ result = kUnknownExpression;
+ }
+ }
+ return result;
+}
+
+
+Expression PreParser::ParseUnaryExpression(bool* ok) {
+ // UnaryExpression ::
+ // PostfixExpression
+ // 'delete' UnaryExpression
+ // 'void' UnaryExpression
+ // 'typeof' UnaryExpression
+ // '++' UnaryExpression
+ // '--' UnaryExpression
+ // '+' UnaryExpression
+ // '-' UnaryExpression
+ // '~' UnaryExpression
+ // '!' UnaryExpression
+
+ i::Token::Value op = peek();
+ if (i::Token::IsUnaryOp(op) || i::Token::IsCountOp(op)) {
+ op = Next();
+ ParseUnaryExpression(ok);
+ return kUnknownExpression;
+ } else {
+ return ParsePostfixExpression(ok);
+ }
+}
+
+
+Expression PreParser::ParsePostfixExpression(bool* ok) {
+ // PostfixExpression ::
+ // LeftHandSideExpression ('++' | '--')?
+
+ Expression expression = ParseLeftHandSideExpression(CHECK_OK);
+ if (!scanner_->has_line_terminator_before_next() &&
+ i::Token::IsCountOp(peek())) {
+ Next();
+ return kUnknownExpression;
+ }
+ return expression;
+}
+
+
+Expression PreParser::ParseLeftHandSideExpression(bool* ok) {
+ // LeftHandSideExpression ::
+ // (NewExpression | MemberExpression) ...
+
+ Expression result;
+ if (peek() == i::Token::NEW) {
+ result = ParseNewExpression(CHECK_OK);
+ } else {
+ result = ParseMemberExpression(CHECK_OK);
+ }
+
+ while (true) {
+ switch (peek()) {
+ case i::Token::LBRACK: {
+ Consume(i::Token::LBRACK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RBRACK, CHECK_OK);
+ if (result == kThisExpression) {
+ result = kThisPropertyExpression;
+ } else {
+ result = kUnknownExpression;
+ }
+ break;
+ }
+
+ case i::Token::LPAREN: {
+ ParseArguments(CHECK_OK);
+ result = kUnknownExpression;
+ break;
+ }
+
+ case i::Token::PERIOD: {
+ Consume(i::Token::PERIOD);
+ ParseIdentifierName(CHECK_OK);
+ if (result == kThisExpression) {
+ result = kThisPropertyExpression;
+ } else {
+ result = kUnknownExpression;
+ }
+ break;
+ }
+
+ default:
+ return result;
+ }
+ }
+}
+
+
+Expression PreParser::ParseNewExpression(bool* ok) {
+ // NewExpression ::
+ // ('new')+ MemberExpression
+
+ // The grammar for new expressions is pretty warped. The keyword
+ // 'new' can either be a part of the new expression (where it isn't
+ // followed by an argument list) or a part of the member expression,
+ // where it must be followed by an argument list. To accommodate
+ // this, we parse the 'new' keywords greedily and keep track of how
+ // many we have parsed. This information is then passed on to the
+ // member expression parser, which is only allowed to match argument
+ // lists as long as it has 'new' prefixes left
+ unsigned new_count = 0;
+ do {
+ Consume(i::Token::NEW);
+ new_count++;
+ } while (peek() == i::Token::NEW);
+
+ return ParseMemberWithNewPrefixesExpression(new_count, ok);
+}
+
+
+Expression PreParser::ParseMemberExpression(bool* ok) {
+ return ParseMemberWithNewPrefixesExpression(0, ok);
+}
+
+
+Expression PreParser::ParseMemberWithNewPrefixesExpression(
+ unsigned new_count, bool* ok) {
+ // MemberExpression ::
+ // (PrimaryExpression | FunctionLiteral)
+ // ('[' Expression ']' | '.' Identifier | Arguments)*
+
+ // Parse the initial primary or function expression.
+ Expression result = kUnknownExpression;
+ if (peek() == i::Token::FUNCTION) {
+ Consume(i::Token::FUNCTION);
+ if (peek() == i::Token::IDENTIFIER) {
+ ParseIdentifier(CHECK_OK);
+ }
+ result = ParseFunctionLiteral(CHECK_OK);
+ } else {
+ result = ParsePrimaryExpression(CHECK_OK);
+ }
+
+ while (true) {
+ switch (peek()) {
+ case i::Token::LBRACK: {
+ Consume(i::Token::LBRACK);
+ ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RBRACK, CHECK_OK);
+ if (result == kThisExpression) {
+ result = kThisPropertyExpression;
+ } else {
+ result = kUnknownExpression;
+ }
+ break;
+ }
+ case i::Token::PERIOD: {
+ Consume(i::Token::PERIOD);
+ ParseIdentifierName(CHECK_OK);
+ if (result == kThisExpression) {
+ result = kThisPropertyExpression;
+ } else {
+ result = kUnknownExpression;
+ }
+ break;
+ }
+ case i::Token::LPAREN: {
+ if (new_count == 0) return result;
+ // Consume one of the new prefixes (already parsed).
+ ParseArguments(CHECK_OK);
+ new_count--;
+ result = kUnknownExpression;
+ break;
+ }
+ default:
+ return result;
+ }
+ }
+}
+
+
+Expression PreParser::ParsePrimaryExpression(bool* ok) {
+ // PrimaryExpression ::
+ // 'this'
+ // 'null'
+ // 'true'
+ // 'false'
+ // Identifier
+ // Number
+ // String
+ // ArrayLiteral
+ // ObjectLiteral
+ // RegExpLiteral
+ // '(' Expression ')'
+
+ Expression result = kUnknownExpression;
+ switch (peek()) {
+ case i::Token::THIS: {
+ Next();
+ result = kThisExpression;
+ break;
+ }
+
+ case i::Token::IDENTIFIER: {
+ ParseIdentifier(CHECK_OK);
+ result = kIdentifierExpression;
+ break;
+ }
+
+ case i::Token::NULL_LITERAL:
+ case i::Token::TRUE_LITERAL:
+ case i::Token::FALSE_LITERAL:
+ case i::Token::NUMBER: {
+ Next();
+ break;
+ }
+ case i::Token::STRING: {
+ Next();
+ result = GetStringSymbol();
+ break;
+ }
+
+ case i::Token::ASSIGN_DIV:
+ result = ParseRegExpLiteral(true, CHECK_OK);
+ break;
+
+ case i::Token::DIV:
+ result = ParseRegExpLiteral(false, CHECK_OK);
+ break;
+
+ case i::Token::LBRACK:
+ result = ParseArrayLiteral(CHECK_OK);
+ break;
+
+ case i::Token::LBRACE:
+ result = ParseObjectLiteral(CHECK_OK);
+ break;
+
+ case i::Token::LPAREN:
+ Consume(i::Token::LPAREN);
+ result = ParseExpression(true, CHECK_OK);
+ Expect(i::Token::RPAREN, CHECK_OK);
+ if (result == kIdentifierExpression) result = kUnknownExpression;
+ break;
+
+ case i::Token::MOD:
+ result = ParseV8Intrinsic(CHECK_OK);
+ break;
+
+ default: {
+ Next();
+ *ok = false;
+ return kUnknownExpression;
+ }
+ }
+
+ return result;
+}
+
+
+Expression PreParser::ParseArrayLiteral(bool* ok) {
+ // ArrayLiteral ::
+ // '[' Expression? (',' Expression?)* ']'
+ Expect(i::Token::LBRACK, CHECK_OK);
+ while (peek() != i::Token::RBRACK) {
+ if (peek() != i::Token::COMMA) {
+ ParseAssignmentExpression(true, CHECK_OK);
+ }
+ if (peek() != i::Token::RBRACK) {
+ Expect(i::Token::COMMA, CHECK_OK);
+ }
+ }
+ Expect(i::Token::RBRACK, CHECK_OK);
+
+ scope_->NextMaterializedLiteralIndex();
+ return kUnknownExpression;
+}
+
+
+Expression PreParser::ParseObjectLiteral(bool* ok) {
+ // ObjectLiteral ::
+ // '{' (
+ // ((IdentifierName | String | Number) ':' AssignmentExpression)
+ // | (('get' | 'set') (IdentifierName | String | Number) FunctionLiteral)
+ // )*[','] '}'
+
+ Expect(i::Token::LBRACE, CHECK_OK);
+ while (peek() != i::Token::RBRACE) {
+ i::Token::Value next = peek();
+ switch (next) {
+ case i::Token::IDENTIFIER: {
+ bool is_getter = false;
+ bool is_setter = false;
+ ParseIdentifierOrGetOrSet(&is_getter, &is_setter, CHECK_OK);
+ if ((is_getter || is_setter) && peek() != i::Token::COLON) {
+ i::Token::Value name = Next();
+ if (name != i::Token::IDENTIFIER &&
+ name != i::Token::NUMBER &&
+ name != i::Token::STRING &&
+ !i::Token::IsKeyword(name)) {
+ *ok = false;
+ return kUnknownExpression;
+ }
+ ParseFunctionLiteral(CHECK_OK);
+ if (peek() != i::Token::RBRACE) {
+ Expect(i::Token::COMMA, CHECK_OK);
+ }
+ continue; // restart the while
+ }
+ break;
+ }
+ case i::Token::STRING:
+ Consume(next);
+ GetStringSymbol();
+ break;
+ case i::Token::NUMBER:
+ Consume(next);
+ break;
+ default:
+ if (i::Token::IsKeyword(next)) {
+ Consume(next);
+ } else {
+ // Unexpected token.
+ *ok = false;
+ return kUnknownExpression;
+ }
+ }
+
+ Expect(i::Token::COLON, CHECK_OK);
+ ParseAssignmentExpression(true, CHECK_OK);
+
+ // TODO(1240767): Consider allowing trailing comma.
+ if (peek() != i::Token::RBRACE) Expect(i::Token::COMMA, CHECK_OK);
+ }
+ Expect(i::Token::RBRACE, CHECK_OK);
+
+ scope_->NextMaterializedLiteralIndex();
+ return kUnknownExpression;
+}
+
+
+Expression PreParser::ParseRegExpLiteral(bool seen_equal,
+ bool* ok) {
+ if (!scanner_->ScanRegExpPattern(seen_equal)) {
+ Next();
+ i::JavaScriptScanner::Location location = scanner_->location();
+ ReportMessageAt(location.beg_pos, location.end_pos,
+ "unterminated_regexp", NULL);
+ *ok = false;
+ return kUnknownExpression;
+ }
+
+ scope_->NextMaterializedLiteralIndex();
+
+ if (!scanner_->ScanRegExpFlags()) {
+ Next();
+ i::JavaScriptScanner::Location location = scanner_->location();
+ ReportMessageAt(location.beg_pos, location.end_pos,
+ "invalid_regexp_flags", NULL);
+ *ok = false;
+ return kUnknownExpression;
+ }
+ Next();
+ return kUnknownExpression;
+}
+
+
+Arguments PreParser::ParseArguments(bool* ok) {
+ // Arguments ::
+ // '(' (AssignmentExpression)*[','] ')'
+
+ Expect(i::Token::LPAREN, CHECK_OK);
+ bool done = (peek() == i::Token::RPAREN);
+ int argc = 0;
+ while (!done) {
+ ParseAssignmentExpression(true, CHECK_OK);
+ argc++;
+ done = (peek() == i::Token::RPAREN);
+ if (!done) Expect(i::Token::COMMA, CHECK_OK);
+ }
+ Expect(i::Token::RPAREN, CHECK_OK);
+ return argc;
+}
+
+
+Expression PreParser::ParseFunctionLiteral(bool* ok) {
+ // Function ::
+ // '(' FormalParameterList? ')' '{' FunctionBody '}'
+
+ // Parse function body.
+ ScopeType outer_scope_type = scope_->type();
+ bool inside_with = scope_->IsInsideWith();
+ Scope function_scope(&scope_, kFunctionScope);
+
+ // FormalParameterList ::
+ // '(' (Identifier)*[','] ')'
+ Expect(i::Token::LPAREN, CHECK_OK);
+ bool done = (peek() == i::Token::RPAREN);
+ while (!done) {
+ ParseIdentifier(CHECK_OK);
+ done = (peek() == i::Token::RPAREN);
+ if (!done) {
+ Expect(i::Token::COMMA, CHECK_OK);
+ }
+ }
+ Expect(i::Token::RPAREN, CHECK_OK);
+
+ Expect(i::Token::LBRACE, CHECK_OK);
+ int function_block_pos = scanner_->location().beg_pos;
+
+ // Determine if the function will be lazily compiled.
+ // Currently only happens to top-level functions.
+ // Optimistically assume that all top-level functions are lazily compiled.
+ bool is_lazily_compiled =
+ (outer_scope_type == kTopLevelScope && !inside_with && allow_lazy_);
+
+ if (is_lazily_compiled) {
+ log_->PauseRecording();
+ ParseSourceElements(i::Token::RBRACE, ok);
+ log_->ResumeRecording();
+ if (!*ok) return kUnknownExpression;
+
+ Expect(i::Token::RBRACE, CHECK_OK);
+
+ int end_pos = scanner_->location().end_pos;
+ log_->LogFunction(function_block_pos, end_pos,
+ function_scope.materialized_literal_count(),
+ function_scope.expected_properties());
+ } else {
+ ParseSourceElements(i::Token::RBRACE, CHECK_OK);
+ Expect(i::Token::RBRACE, CHECK_OK);
+ }
+ return kUnknownExpression;
+}
+
+
+Expression PreParser::ParseV8Intrinsic(bool* ok) {
+ // CallRuntime ::
+ // '%' Identifier Arguments
+
+ Expect(i::Token::MOD, CHECK_OK);
+ ParseIdentifier(CHECK_OK);
+ ParseArguments(CHECK_OK);
+
+ return kUnknownExpression;
+}
+
+
+void PreParser::ExpectSemicolon(bool* ok) {
+ // Check for automatic semicolon insertion according to
+ // the rules given in ECMA-262, section 7.9, page 21.
+ i::Token::Value tok = peek();
+ if (tok == i::Token::SEMICOLON) {
+ Next();
+ return;
+ }
+ if (scanner_->has_line_terminator_before_next() ||
+ tok == i::Token::RBRACE ||
+ tok == i::Token::EOS) {
+ return;
+ }
+ Expect(i::Token::SEMICOLON, ok);
+}
+
+
+Identifier PreParser::GetIdentifierSymbol() {
+ const char* literal_chars = scanner_->literal_string();
+ int literal_length = scanner_->literal_length();
+ int identifier_pos = scanner_->location().beg_pos;
+
+ log_->LogSymbol(identifier_pos, literal_chars, literal_length);
+
+ return kUnknownExpression;
+}
+
+
+Expression PreParser::GetStringSymbol() {
+ const char* literal_chars = scanner_->literal_string();
+ int literal_length = scanner_->literal_length();
+
+ int literal_position = scanner_->location().beg_pos;
+ log_->LogSymbol(literal_position, literal_chars, literal_length);
+
+ return kUnknownExpression;
+}
+
+
+Identifier PreParser::ParseIdentifier(bool* ok) {
+ Expect(i::Token::IDENTIFIER, ok);
+ if (!*ok) return kUnknownIdentifier;
+ return GetIdentifierSymbol();
+}
+
+
+Identifier PreParser::ParseIdentifierName(bool* ok) {
+ i::Token::Value next = Next();
+ if (i::Token::IsKeyword(next)) {
+ int pos = scanner_->location().beg_pos;
+ const char* keyword = i::Token::String(next);
+ log_->LogSymbol(pos, keyword, i::StrLength(keyword));
+ return kUnknownExpression;
+ }
+ if (next == i::Token::IDENTIFIER) {
+ return GetIdentifierSymbol();
+ }
+ *ok = false;
+ return kUnknownIdentifier;
+}
+
+
+// This function reads an identifier and determines whether or not it
+// is 'get' or 'set'. The reason for not using ParseIdentifier and
+// checking on the output is that this involves heap allocation which
+// we can't do during preparsing.
+Identifier PreParser::ParseIdentifierOrGetOrSet(bool* is_get,
+ bool* is_set,
+ bool* ok) {
+ Expect(i::Token::IDENTIFIER, CHECK_OK);
+ if (scanner_->literal_length() == 3) {
+ const char* token = scanner_->literal_string();
+ *is_get = strncmp(token, "get", 3) == 0;
+ *is_set = !*is_get && strncmp(token, "set", 3) == 0;
+ }
+ return GetIdentifierSymbol();
+}
+
+#undef CHECK_OK
+} } // v8::preparser
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-20 02:28:01 +0000