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c10b1cef65
This moves trailing closures from expr-postfix up to the level of expr, and introduces an intermediate level (expr-basic) for places that need to parse expressions followed by curly braces, such as if/while/switch/for. Trailing closures are still restricted to occur after expr-postfix, although the parser itself parses a slightly more general and then complains if it got more than an expr-postfix. Swift SVN r5256
681 lines
22 KiB
C++
681 lines
22 KiB
C++
//===--- ParseStmt.cpp - Swift Language Parser for Statements -------------===//
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//
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// This source file is part of the Swift.org open source project
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//
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// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
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// Licensed under Apache License v2.0 with Runtime Library Exception
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//
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// See http://swift.org/LICENSE.txt for license information
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// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
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//
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//===----------------------------------------------------------------------===//
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//
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// Statement Parsing and AST Building
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//
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//===----------------------------------------------------------------------===//
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#include "Parser.h"
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#include "swift/AST/Attr.h"
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#include "swift/AST/Decl.h"
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#include "swift/Parse/Lexer.h"
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#include "llvm/ADT/PointerUnion.h"
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#include "llvm/ADT/OwningPtr.h"
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#include "llvm/ADT/Twine.h"
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#include "llvm/Support/SaveAndRestore.h"
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using namespace swift;
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/// isStartOfStmtOtherThanAssignment - Return true if the specified token starts
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/// a statement (other than assignment, which starts looking like an expr).
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///
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/// Note this also returns true for '{' which can be the start of a stmt-brace
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/// or the start of an expr-closure. This ambiguity is resolved towards
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/// statements when not in a subexpression context.
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bool Parser::isStartOfStmtOtherThanAssignment(const Token &Tok) {
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switch (Tok.getKind()) {
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default: return false;
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case tok::kw_return:
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case tok::kw_if:
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case tok::kw_while:
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case tok::kw_do:
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case tok::kw_for:
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case tok::kw_break:
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case tok::kw_continue:
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case tok::kw_fallthrough:
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case tok::kw_switch:
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case tok::kw_case:
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case tok::kw_default:
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return true;
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}
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}
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/// isFuncExpr - Return true if this two token sequence is the start of a func
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/// expression (i.e. not a func *decl* or something else).
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static bool isFuncExpr(const Token &Tok1, const Token &Tok2) {
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if (Tok1.isNot(tok::kw_func)) return false;
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// "func identifier" and "func [attribute]" is a func declaration,
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// otherwise we have a func expression.
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return Tok2.isNot(tok::identifier) && Tok2.isNotAnyOperator() &&
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Tok2.isNot(tok::l_square);
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}
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/// isStartOfDecl - Return true if this is the start of a decl or decl-import.
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bool Parser::isStartOfDecl(const Token &Tok, const Token &Tok2) {
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switch (Tok.getKind()) {
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case tok::kw_func:
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// "func identifier" and "func [attribute]" is a func declaration,
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// otherwise we have a func expression.
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return !isFuncExpr(Tok, Tok2);
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case tok::kw_static:
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return Tok2.is(tok::kw_func);
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case tok::kw_extension:
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case tok::kw_var:
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case tok::kw_typealias:
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case tok::kw_oneof:
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case tok::kw_struct:
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case tok::kw_class:
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case tok::kw_import:
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case tok::kw_subscript:
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case tok::kw_constructor:
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case tok::kw_destructor:
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return true;
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case tok::kw_protocol:
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return !(Tok2.isAnyOperator() && Tok2.getText().equals("<"));
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default:
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return isStartOfOperatorDecl(Tok, Tok2);
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}
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}
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/// parseExprOrStmtAssign
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/// expr-or-stmt-assign:
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/// expr
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/// stmt-assign
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///
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/// expr-or-stmt-assign-basic:
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/// expr-basic
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/// stmt-assign-basic
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///
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/// stmt-assign-basic:
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/// expr-basic '=' expr-basic
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///
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/// \para usesExprBasic If true, parse expr-or-stmt-assign-basic rather than
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/// expr-or-stmt-assign.
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bool Parser::parseExprOrStmtAssign(ExprStmtOrDecl &Result, bool usesExprBasic) {
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NullablePtr<Expr> ResultExpr = parseExpr(diag::expected_expr, usesExprBasic);
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if (ResultExpr.isNull())
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return true;
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Result = ResultExpr.get();
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// Check for assignment. If we don't have it, then we just have a
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// simple expression.
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if (Tok.isNot(tok::equal))
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return false;
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SourceLoc EqualLoc = consumeToken();
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NullablePtr<Expr> RHSExpr = parseExpr(diag::expected_expr_assignment,
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usesExprBasic);
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if (RHSExpr.isNull())
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return true;
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Result = new (Context) AssignStmt(ResultExpr.get(),
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EqualLoc, RHSExpr.get());
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return false;
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}
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bool Parser::parseExprOrStmt(ExprStmtOrDecl &Result) {
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if (Tok.is(tok::semi)) {
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diagnose(Tok.getLoc(), diag::illegal_semi_stmt)
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.fixItRemove(SourceRange(Tok.getLoc()));
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consumeToken();
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return true;
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} else if (isStartOfStmtOtherThanAssignment(Tok)) {
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NullablePtr<Stmt> Res = parseStmtOtherThanAssignment();
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if (Res.isNull())
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return true;
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Result = Res.get();
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return false;
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}
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return parseExprOrStmtAssign(Result);
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}
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static bool isTerminatorForBraceItemListKind(const Token &Tok,
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BraceItemListKind Kind,
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ArrayRef<Parser::ExprStmtOrDecl> ParsedDecls) {
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switch (Kind) {
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case BraceItemListKind::Brace:
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return false;
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case BraceItemListKind::Property:
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return Tok.isContextualKeyword("get") || Tok.isContextualKeyword("set");
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case BraceItemListKind::Case:
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return Tok.is(tok::kw_case) || Tok.is(tok::kw_default);
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case BraceItemListKind::TopLevelCode:
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// When parsing the top level executable code for a module, if we parsed
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// some executable code, then we're done. We want to process (name bind,
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// type check, etc) decls one at a time to make sure that there are not
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// forward type references, etc. There is an outer loop around the parser
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// that will reinvoke the parser at the top level on each statement until
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// EOF. In contrast, it is ok to have forward references between classes,
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// functions, etc.
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for (auto I : ParsedDecls) {
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if (isa<TopLevelCodeDecl>(I.get<Decl*>()))
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// Only bail out if the next token is at the start of a line. If we
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// don't, then we may accidentally allow things like "a = 1 b = 4".
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// FIXME: This is really dubious. This will reject some things, but
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// allow other things we don't want.
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if (Tok.isAtStartOfLine())
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return true;
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}
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return false;
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}
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}
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/// brace-item:
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/// decl
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/// expr
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/// stmt
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/// stmt:
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/// ';'
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/// stmt-assign
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/// stmt-return
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/// stmt-if
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/// stmt-for-c-style
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/// stmt-for-each
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/// stmt-switch
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/// stmt-assign:
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/// expr '=' expr
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void Parser::parseBraceItems(SmallVectorImpl<ExprStmtOrDecl> &Entries,
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bool IsTopLevel, BraceItemListKind Kind) {
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// This forms a lexical scope.
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Scope BraceScope(this, !IsTopLevel);
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SmallVector<Decl*, 8> TmpDecls;
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bool previousHadSemi = true;
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while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof) &&
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Tok.isNot(tok::kw_sil) &&
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!isTerminatorForBraceItemListKind(Tok, Kind, Entries)) {
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bool NeedParseErrorRecovery = false;
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ExprStmtOrDecl Result;
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// If the previous statement didn't have a semicolon and this new
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// statement doesn't start a line, complain.
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if (!previousHadSemi && !Tok.isAtStartOfLine()) {
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SourceLoc EndOfPreviousLoc = Lexer::getLocForEndOfToken(SourceMgr,
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PreviousLoc);
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diagnose(EndOfPreviousLoc, diag::statement_same_line_without_semi)
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.fixItInsert(EndOfPreviousLoc, ";");
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// FIXME: Add semicolon to the AST?
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}
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// Parse the decl, stmt, or expression.
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previousHadSemi = false;
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if (isStartOfDecl(Tok, peekToken())) {
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if (parseDecl(TmpDecls, IsTopLevel ? PD_AllowTopLevel : PD_Default))
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NeedParseErrorRecovery = true;
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else {
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for (Decl *D : TmpDecls)
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Entries.push_back(D);
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if (!TmpDecls.empty())
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previousHadSemi = TmpDecls.back()->TrailingSemiLoc.isValid();
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}
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TmpDecls.clear();
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} else if (IsTopLevel && IsMainModule) {
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// If this is a statement or expression at the top level of the module,
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// Parse it as a child of a TopLevelCodeDecl.
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auto *TLCD = new (Context) TopLevelCodeDecl(CurDeclContext);
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ContextChange CC(*this, TLCD);
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SourceLoc StartLoc = Tok.getLoc();
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if (parseExprOrStmt(Result)) {
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NeedParseErrorRecovery = true;
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} else {
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auto Brace = BraceStmt::create(Context, StartLoc, Result, Tok.getLoc());
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TLCD->setBody(Brace);
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Entries.push_back(TLCD);
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}
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} else {
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SourceLoc StartLoc = Tok.getLoc();
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if (parseExprOrStmt(Result))
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NeedParseErrorRecovery = true;
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else {
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// If this is a normal library, you can't have expressions or statements
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// outside at the top level. Diagnose this error.
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if (IsTopLevel) {
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if (!NeedParseErrorRecovery)
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diagnose(StartLoc,
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Result.is<Stmt*>() ? diag::illegal_top_level_stmt :
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diag::illegal_top_level_expr);
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} else {
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Entries.push_back(Result);
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}
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}
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}
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if (!NeedParseErrorRecovery && !previousHadSemi && Tok.is(tok::semi)) {
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if (Result.is<Expr*>()) {
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Result.get<Expr*>()->TrailingSemiLoc = consumeToken(tok::semi);
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} else {
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Result.get<Stmt*>()->TrailingSemiLoc = consumeToken(tok::semi);
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}
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previousHadSemi = true;
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}
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// If we had a parse error, skip to the start of the next stmt or decl. It
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// would be ideal to stop at the start of the next expression (e.g. "X = 4")
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// but distinguishing the start of an expression from the middle of one is
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// "hard".
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if (NeedParseErrorRecovery) {
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skipUntilDeclStmtRBrace();
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// If we have to recover, pretend that we had a semicolon; it's less
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// noisy that way.
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previousHadSemi = true;
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}
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}
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}
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/// Recover from a 'case' or 'default' outside of a 'switch' by consuming up to
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/// the next ':'.
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static NullablePtr<Stmt> recoverFromInvalidCase(Parser &P) {
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assert(P.Tok.is(tok::kw_case) || P.Tok.is(tok::kw_default)
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&& "not case or default?!");
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P.diagnose(P.Tok.getLoc(), diag::case_outside_of_switch, P.Tok.getText());
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P.skipUntil(tok::colon);
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// FIXME: Return an ErrorStmt?
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return nullptr;
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}
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/// parseStmtOtherThanAssignment - Note that this doesn't handle the
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/// "expr '=' expr" production.
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///
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NullablePtr<Stmt> Parser::parseStmtOtherThanAssignment() {
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switch (Tok.getKind()) {
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default:
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diagnose(Tok, diag::expected_stmt);
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return 0;
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case tok::kw_return: return parseStmtReturn();
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case tok::kw_if: return parseStmtIf();
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case tok::kw_while: return parseStmtWhile();
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case tok::kw_do: return parseStmtDoWhile();
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case tok::kw_for: return parseStmtFor();
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case tok::kw_switch: return parseStmtSwitch();
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/// 'case' and 'default' are only valid at the top level of a switch.
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case tok::kw_case:
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case tok::kw_default: return recoverFromInvalidCase(*this);
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case tok::kw_break:
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return new (Context) BreakStmt(consumeToken(tok::kw_break));
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case tok::kw_continue:
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return new (Context) ContinueStmt(consumeToken(tok::kw_continue));
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case tok::kw_fallthrough:
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return new (Context) FallthroughStmt(consumeToken(tok::kw_fallthrough));
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}
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}
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/// parseBraceItemList - A brace enclosed expression/statement/decl list. For
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/// example { 1; 4+5; } or { 1; 2 }. Always occurs as part of some other stmt
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/// or decl.
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///
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/// brace-item-list:
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/// '{' brace-item* '}'
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///
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NullablePtr<BraceStmt> Parser::parseBraceItemList(Diag<> ID) {
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if (Tok.isNot(tok::l_brace)) {
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diagnose(Tok.getLoc(), ID);
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return 0;
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}
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SourceLoc LBLoc = consumeToken(tok::l_brace);
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// The pipe is not a delimiter within braces.
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llvm::SaveAndRestore<bool> pipeIsDelimiter(PipeIsDelimiter, false);
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SmallVector<ExprStmtOrDecl, 16> Entries;
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SourceLoc RBLoc;
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parseBraceItems(Entries, false /*NotTopLevel*/);
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if (parseMatchingToken(tok::r_brace, RBLoc,
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diag::expected_rbrace_in_brace_stmt, LBLoc))
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return 0;
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return BraceStmt::create(Context, LBLoc, Entries, RBLoc);
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}
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/// parseStmtReturn
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///
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/// stmt-return:
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/// return expr?
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///
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NullablePtr<Stmt> Parser::parseStmtReturn() {
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SourceLoc ReturnLoc = consumeToken(tok::kw_return);
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// Handle the ambiguity between consuming the expression and allowing the
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// enclosing stmt-brace to get it by eagerly eating it unless the return is
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// followed by a '}', ';', or statement keyword.
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Expr *RetExpr = nullptr;
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if (Tok.isNot(tok::r_brace) && Tok.isNot(tok::semi) &&
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!isStartOfStmtOtherThanAssignment(Tok)) {
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NullablePtr<Expr> Result = parseExpr(diag::expected_expr_return);
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if (Result.isNull())
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return 0;
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RetExpr = Result.get();
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}
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return new (Context) ReturnStmt(ReturnLoc, RetExpr);
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}
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///
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/// stmt-if:
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/// 'if' expr-basic stmt-brace stmt-if-else?
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/// stmt-if-else:
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/// 'else' stmt-brace
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/// 'else' stmt-if
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NullablePtr<Stmt> Parser::parseStmtIf() {
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SourceLoc IfLoc = consumeToken(tok::kw_if);
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NullablePtr<Expr> Condition = parseExprBasic(diag::expected_expr_if);
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if (Condition.isNull()) return 0;
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NullablePtr<BraceStmt> NormalBody =
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parseBraceItemList(diag::expected_lbrace_after_if);
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if (NormalBody.isNull())
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return 0;
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NullablePtr<Stmt> ElseBody;
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SourceLoc ElseLoc = Tok.getLoc();
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if (consumeIf(tok::kw_else)) {
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if (Tok.is(tok::kw_if))
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ElseBody = parseStmtIf();
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else
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ElseBody = parseBraceItemList(diag::expected_lbrace_after_else)
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.getPtrOrNull();
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if (ElseBody.isNull())
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return 0;
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} else {
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ElseLoc = SourceLoc();
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}
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// If our condition and normal expression parsed correctly, build an AST.
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return new (Context) IfStmt(IfLoc, Condition.get(), NormalBody.get(),
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ElseLoc, ElseBody.getPtrOrNull());
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}
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///
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/// stmt-while:
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/// 'while' expr-basic stmt-brace
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NullablePtr<Stmt> Parser::parseStmtWhile() {
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SourceLoc WhileLoc = consumeToken(tok::kw_while);
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NullablePtr<Expr> Condition = parseExprBasic(diag::expected_expr_while);
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if (Condition.isNull()) return 0;
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NullablePtr<BraceStmt> Body =
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parseBraceItemList(diag::expected_lbrace_after_while);
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if (Body.isNull())
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return 0;
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// If our normal expression parsed correctly, build an AST.
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return new (Context) WhileStmt(WhileLoc, Condition.get(), Body.get());
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}
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///
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/// stmt-do-while:
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/// 'do' stmt-brace 'while' expr
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NullablePtr<Stmt> Parser::parseStmtDoWhile() {
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SourceLoc DoLoc = consumeToken(tok::kw_do), WhileLoc;
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NullablePtr<BraceStmt> Body =
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parseBraceItemList(diag::expected_lbrace_after_do);
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if (Body.isNull()) return 0;
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if (parseToken(tok::kw_while, WhileLoc, diag::expected_while_in_dowhile))
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return 0;
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NullablePtr<Expr> Condition = parseExpr(diag::expected_expr_do_while);
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if (Condition.isNull()) return 0;
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return new (Context) DoWhileStmt(DoLoc, Condition.get(), WhileLoc, Body.get());
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}
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NullablePtr<Stmt> Parser::parseStmtFor() {
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SourceLoc ForLoc = consumeToken(tok::kw_for);
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// The c-style-for loop and foreach-style-for loop are conflated together into
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// a single keyword, so we have to do some lookahead to resolve what is going
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// on.
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if (Tok.is(tok::l_paren)) {
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auto Backup = Tok;
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consumeToken(tok::l_paren);
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skipUntil(tok::r_paren);
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bool IsCStyle = peekToken().is(tok::l_brace);
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Tok = Backup;
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L->backtrackToToken(Backup);
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if (IsCStyle)
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return parseStmtForCStyle(ForLoc);
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return parseStmtForEach(ForLoc);
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}
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// If we have a leading identifier followed by a ':' or 'in', then this is a
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// pattern, so it is foreach.
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if (Tok.is(tok::identifier) &&
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(peekToken().is(tok::colon) || peekToken().isContextualKeyword("in")))
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return parseStmtForEach(ForLoc);
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// Otherwise, this is some sort of c-style for loop.
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return parseStmtForCStyle(ForLoc);
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}
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/// stmt-for-c-style:
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/// 'for' stmt-for-c-style-init? ';' expr? ';' expr-or-stmt-assign-basic?
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/// stmt-brace
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/// stmt-for-c-style-init:
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/// decl-var
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/// expr-basic-or-stmt-assign
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NullablePtr<Stmt> Parser::parseStmtForCStyle(SourceLoc ForLoc) {
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SourceLoc Semi1Loc, Semi2Loc;
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SourceLoc LPLoc, RPLoc;
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bool LPLocConsumed = false;
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|
|
ExprStmtOrDecl First;
|
|
SmallVector<Decl*, 2> FirstDecls;
|
|
NullablePtr<Expr> Second;
|
|
ExprStmtOrDecl Third;
|
|
NullablePtr<BraceStmt> Body;
|
|
|
|
// Introduce a new scope to contain any var decls in the init value.
|
|
Scope ForScope(this, /*AllowLookup=*/true);
|
|
|
|
if (Tok.is(tok::l_paren)) {
|
|
LPLoc = consumeToken();
|
|
LPLocConsumed = true;
|
|
}
|
|
// Parse the first part, either a var, expr, or stmt-assign.
|
|
if (Tok.is(tok::kw_var)) {
|
|
if (parseDeclVar(false, FirstDecls)) return 0;
|
|
} else if ((Tok.isNot(tok::semi) && parseExprOrStmtAssign(First)))
|
|
return 0;
|
|
|
|
// Parse the rest of the statement.
|
|
if (parseToken(tok::semi, Semi1Loc, diag::expected_semi_for_stmt))
|
|
return 0;
|
|
|
|
if ((Tok.isNot(tok::semi) && Tok.isNot(tok::l_brace) &&
|
|
(Second = parseExpr(diag::expected_cond_for_stmt)).isNull()) ||
|
|
parseToken(tok::semi, Semi2Loc, diag::expected_semi_for_stmt) ||
|
|
(Tok.isNot(tok::l_brace) && parseExprOrStmtAssign(Third, true)))
|
|
return 0;
|
|
|
|
if (LPLocConsumed && parseMatchingToken(tok::r_paren, RPLoc,
|
|
diag::expected_rparen_for_stmt,LPLoc))
|
|
return 0;
|
|
|
|
if ((Body = parseBraceItemList(diag::expected_lbrace_after_for)).isNull())
|
|
return 0;
|
|
|
|
PointerUnion<Expr*, AssignStmt*> Initializer, Increment;
|
|
if (First.isNull())
|
|
;
|
|
else if (First.is<Expr*>())
|
|
Initializer = First.get<Expr*>();
|
|
else
|
|
Initializer = cast<AssignStmt>(First.get<Stmt*>());
|
|
|
|
if (Third.isNull())
|
|
;
|
|
else if (Third.is<Expr*>())
|
|
Increment = Third.get<Expr*>();
|
|
else
|
|
Increment = cast<AssignStmt>(Third.get<Stmt*>());
|
|
|
|
ArrayRef<Decl*> FirstDeclsContext;
|
|
if (!FirstDecls.empty())
|
|
FirstDeclsContext = Context.AllocateCopy(FirstDecls);
|
|
|
|
return new (Context) ForStmt(ForLoc, Initializer, FirstDeclsContext,
|
|
Semi1Loc, Second,
|
|
Semi2Loc, Increment, Body.get());
|
|
}
|
|
|
|
///
|
|
/// stmt-for-each:
|
|
/// 'for' pattern 'in' expr-basic stmt-brace
|
|
NullablePtr<Stmt> Parser::parseStmtForEach(SourceLoc ForLoc) {
|
|
NullablePtr<Pattern> Pattern = parsePattern();
|
|
|
|
if (!Tok.isContextualKeyword("in")) {
|
|
if (Pattern.isNonNull())
|
|
diagnose(Tok.getLoc(), diag::expected_foreach_in);
|
|
return nullptr;
|
|
}
|
|
SourceLoc InLoc = consumeToken();
|
|
|
|
// expr
|
|
NullablePtr<Expr> Container
|
|
= parseExprBasic(diag::expected_foreach_container);
|
|
|
|
// Introduce a new scope and place the variables in the pattern into that
|
|
// scope.
|
|
// FIXME: We may want to merge this scope with the scope introduced by
|
|
// the stmt-brace, as in C++.
|
|
Scope ForEachScope(this, /*AllowLookup=*/true);
|
|
if (Pattern.isNonNull()) {
|
|
SmallVector<Decl *, 2> Decls;
|
|
DeclAttributes Attributes;
|
|
addVarsToScope(Pattern.get(), Decls, Attributes);
|
|
}
|
|
// stmt-brace
|
|
NullablePtr<BraceStmt> Body =
|
|
parseBraceItemList(diag::expected_foreach_lbrace);
|
|
|
|
if (Pattern.isNull() || Container.isNull() || Body.isNull())
|
|
return nullptr;
|
|
|
|
return new (Context) ForEachStmt(ForLoc, Pattern.get(), InLoc,
|
|
Container.get(), Body.get());
|
|
}
|
|
|
|
///
|
|
/// stmt-switch:
|
|
/// 'switch' expr-basic '{' stmt-case* '}'
|
|
NullablePtr<Stmt> Parser::parseStmtSwitch() {
|
|
SourceLoc switchLoc = consumeToken(tok::kw_switch);
|
|
NullablePtr<Expr> subjectExpr = parseExprBasic(diag::expected_switch_expr);
|
|
|
|
if (subjectExpr.isNull())
|
|
return nullptr;
|
|
|
|
if (!Tok.is(tok::l_brace)) {
|
|
diagnose(Tok.getLoc(), diag::expected_lbrace_after_switch);
|
|
return nullptr;
|
|
}
|
|
|
|
SourceLoc lBraceLoc = consumeToken(tok::l_brace);
|
|
SourceLoc rBraceLoc;
|
|
|
|
llvm::SmallVector<CaseStmt*, 8> cases;
|
|
while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof)) {
|
|
NullablePtr<CaseStmt> c = parseStmtCase();
|
|
if (!c.isNull())
|
|
cases.push_back(c.get());
|
|
}
|
|
|
|
if (parseMatchingToken(tok::r_brace, rBraceLoc,
|
|
diag::expected_rbrace_switch, lBraceLoc))
|
|
return nullptr;
|
|
|
|
// Synthesize a VarDecl to bind the subject to.
|
|
VarDecl *subjectVar = new (Context) VarDecl(SourceLoc(),
|
|
Context.getIdentifier("$switch"),
|
|
Type(),
|
|
CurDeclContext);
|
|
|
|
return SwitchStmt::create(switchLoc,
|
|
subjectExpr.get(),
|
|
subjectVar,
|
|
lBraceLoc,
|
|
cases,
|
|
rBraceLoc,
|
|
Context);
|
|
}
|
|
|
|
///
|
|
/// stmt-case:
|
|
/// 'case' expr (',' expr)* ':' stmt-brace-item*
|
|
/// 'default' ':' stmt-brace-item*
|
|
NullablePtr<CaseStmt> Parser::parseStmtCase() {
|
|
SourceLoc caseLoc = Tok.getLoc();
|
|
StringRef caseLabel = Tok.getText();
|
|
|
|
llvm::SmallVector<Expr*, 2> valueExprs;
|
|
if (Tok.is(tok::kw_case)) {
|
|
consumeToken(tok::kw_case);
|
|
NullablePtr<Expr> expr = parseExpr(diag::expected_case_expr);
|
|
if (expr.isNull())
|
|
skipUntil(tok::colon);
|
|
else
|
|
valueExprs.push_back(expr.get());
|
|
|
|
while (Tok.is(tok::comma)) {
|
|
consumeToken(tok::comma);
|
|
NullablePtr<Expr> expr = parseExpr(diag::expected_case_expr);
|
|
if (expr.isNull())
|
|
skipUntil(tok::colon);
|
|
else
|
|
valueExprs.push_back(expr.get());
|
|
}
|
|
} else if (Tok.is(tok::kw_default)) {
|
|
consumeToken(tok::kw_default);
|
|
} else {
|
|
// If we see a statement before any 'case' or 'default', give a descriptive
|
|
// error and recover by trying to parse the statement.
|
|
ExprStmtOrDecl junk;
|
|
if (!parseExprOrStmt(junk)) {
|
|
diagnose(caseLoc, diag::stmt_in_switch_not_covered_by_case);
|
|
return nullptr;
|
|
}
|
|
|
|
// Otherwise, we got something malformed, so try to find the closing brace
|
|
// of the switch and bail out.
|
|
skipUntil(tok::r_brace);
|
|
return nullptr;
|
|
}
|
|
|
|
if (Tok.isNot(tok::colon)) {
|
|
diagnose(Tok.getLoc(), diag::expected_case_colon, caseLabel);
|
|
return nullptr;
|
|
}
|
|
|
|
SourceLoc colonLoc = consumeToken(tok::colon);
|
|
|
|
llvm::SmallVector<ExprStmtOrDecl, 8> bodyItems;
|
|
parseBraceItems(bodyItems, /*isTopLevel*/ false, BraceItemListKind::Case);
|
|
BraceStmt *body = BraceStmt::create(Context,
|
|
colonLoc, bodyItems, Tok.getLoc());
|
|
|
|
return CaseStmt::create(caseLoc, valueExprs, colonLoc, body, Context);
|
|
}
|
|
|