Add support for C++'s "type-specifier ( expression-list )" expression:

-The Parser calls a new "ActOnCXXTypeConstructExpr" action.
-Sema, depending on the type and expressions number:
   -If the type is a class, it will treat it as a class constructor. [TODO]
   -If there's only one expression (i.e. "int(0.5)" ), creates a new "CXXFunctionalCastExpr" Expr node
   -If there are no expressions (i.e "int()" ), creates a new "CXXZeroInitValueExpr" Expr node.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@55177 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 172 insertions, 2 deletions

diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index 9eccd06da1..d4b46982ac 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -20,6 +20,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Parse/Parser.h"
+#include "clang/Parse/DeclSpec.h"
 #include "clang/Basic/Diagnostic.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/SmallString.h"
@@ -372,6 +373,8 @@ Parser::ParseRHSOfBinaryExpression(ExprResult LHS, unsigned MinPrec) {
 /// [OBJC]  '@protocol' '(' identifier ')'             
 /// [OBJC]  '@encode' '(' type-name ')'                
 /// [OBJC]  objc-string-literal
+/// [C++]   simple-type-specifier '(' expression-list[opt] ')'      [C++ 5.2.3]
+/// [C++]   typename-specifier '(' expression-list[opt] ')'         [TODO]
 /// [C++]   'const_cast' '<' type-name '>' '(' expression ')'       [C++ 5.2p1]
 /// [C++]   'dynamic_cast' '<' type-name '>' '(' expression ')'     [C++ 5.2p1]
 /// [C++]   'reinterpret_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1]
@@ -446,8 +449,17 @@ Parser::ExprResult Parser::ParseCastExpression(bool isUnaryExpression) {
   case tok::kw_false:
     return ParseCXXBoolLiteral();
 
-  case tok::identifier: {      // primary-expression: identifier
-                               // constant: enumeration-constant
+  case tok::identifier: {
+    if (getLang().CPlusPlus &&
+        Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope)) {
+      // Handle C++ function-style cast, e.g. "T(4.5)" where T is a typedef for
+      // double.
+      goto HandleType;
+    }
+    
+    // primary-expression: identifier
+    // constant: enumeration-constant
+
     // Consume the identifier so that we can see if it is followed by a '('.
     // Function designators are allowed to be undeclared (C99 6.5.1p2), so we
     // need to know whether or not this identifier is a function designator or
@@ -545,6 +557,35 @@ Parser::ExprResult Parser::ParseCastExpression(bool isUnaryExpression) {
     Res = ParseCXXThis();
     // This can be followed by postfix-expr pieces.
     return ParsePostfixExpressionSuffix(Res);
+
+  case tok::kw_char:
+  case tok::kw_wchar_t:
+  case tok::kw_bool:
+  case tok::kw_short:
+  case tok::kw_int:
+  case tok::kw_long:
+  case tok::kw_signed:
+  case tok::kw_unsigned:
+  case tok::kw_float:
+  case tok::kw_double:
+  case tok::kw_void:
+  case tok::kw_typeof: {
+    if (!getLang().CPlusPlus)
+      goto UnhandledToken;
+  HandleType:
+    // postfix-expression: simple-type-specifier '(' expression-list[opt] ')'
+    //
+    DeclSpec DS;
+    ParseCXXSimpleTypeSpecifier(DS);
+    if (Tok.isNot(tok::l_paren))
+      return Diag(Tok.getLocation(), diag::err_expected_lparen_after_type,
+                  DS.getSourceRange());
+
+    Res = ParseCXXTypeConstructExpression(DS);
+    // This can be followed by postfix-expr pieces.
+    return ParsePostfixExpressionSuffix(Res);
+  }
+
   case tok::at: {
     SourceLocation AtLoc = ConsumeToken();
     return ParseObjCAtExpression(AtLoc);
@@ -555,6 +596,7 @@ Parser::ExprResult Parser::ParseCastExpression(bool isUnaryExpression) {
       return ParsePostfixExpressionSuffix(ParseObjCMessageExpression());
     // FALL THROUGH.
   default:
+  UnhandledToken:
     Diag(Tok, diag::err_expected_expression);
     return ExprResult(true);
   }
diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index 45f482792d..bd8e7d510e 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -13,6 +13,7 @@
 
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Parse/Parser.h"
+#include "clang/Parse/DeclSpec.h"
 using namespace clang;
 
 /// ParseCXXCasts - This handles the various ways to cast expressions to another
@@ -114,3 +115,130 @@ Parser::ExprResult Parser::ParseCXXThis() {
   SourceLocation ThisLoc = ConsumeToken();
   return Actions.ActOnCXXThis(ThisLoc);
 }
+
+/// ParseCXXTypeConstructExpression - Parse construction of a specified type.
+/// Can be interpreted either as function-style casting ("int(x)")
+/// or class type construction ("ClassType(x,y,z)")
+/// or creation of a value-initialized type ("int()").
+///
+///       postfix-expression: [C++ 5.2p1]
+///         simple-type-specifier '(' expression-list[opt] ')'      [C++ 5.2.3]
+///         typename-specifier '(' expression-list[opt] ')'         [TODO]
+///
+Parser::ExprResult Parser::ParseCXXTypeConstructExpression(const DeclSpec &DS) {
+  Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+  TypeTy *TypeRep = Actions.ActOnTypeName(CurScope, DeclaratorInfo).Val;
+
+  assert(Tok.is(tok::l_paren) && "Expected '('!");
+  SourceLocation LParenLoc = ConsumeParen();
+
+  ExprListTy Exprs;
+  CommaLocsTy CommaLocs;
+
+  if (Tok.isNot(tok::r_paren)) {
+    if (ParseExpressionList(Exprs, CommaLocs)) {
+      SkipUntil(tok::r_paren);
+      return ExprResult(true);
+    }
+  }
+
+  // Match the ')'.
+  SourceLocation RParenLoc = MatchRHSPunctuation(tok::r_paren, LParenLoc);
+
+  assert((Exprs.size() == 0 || Exprs.size()-1 == CommaLocs.size())&&
+         "Unexpected number of commas!");
+  return Actions.ActOnCXXTypeConstructExpr(DS.getSourceRange(), TypeRep,
+                                           LParenLoc,
+                                           &Exprs[0], Exprs.size(),
+                                           &CommaLocs[0], RParenLoc);
+}
+
+/// ParseCXXSimpleTypeSpecifier - [C++ 7.1.5.2] Simple type specifiers.
+/// This should only be called when the current token is known to be part of
+/// simple-type-specifier.
+///
+///       simple-type-specifier:
+///         '::'[opt] nested-name-specifier[opt] type-name                [TODO]
+///         '::'[opt] nested-name-specifier 'template' simple-template-id [TODO]
+///         char
+///         wchar_t
+///         bool
+///         short
+///         int
+///         long
+///         signed
+///         unsigned
+///         float
+///         double
+///         void
+/// [GNU]   typeof-specifier
+/// [C++0x] auto               [TODO]
+///
+///       type-name:
+///         class-name
+///         enum-name
+///         typedef-name
+///
+void Parser::ParseCXXSimpleTypeSpecifier(DeclSpec &DS) {
+  DS.SetRangeStart(Tok.getLocation());
+  const char *PrevSpec;
+  SourceLocation Loc = Tok.getLocation();
+  
+  switch (Tok.getKind()) {
+  default: 
+    assert(0 && "Not a simple-type-specifier token!");
+    abort();
+      
+  // type-name
+  case tok::identifier: {
+    TypeTy *TypeRep = Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope);
+    assert(TypeRep && "Identifier wasn't a type-name!");
+    DS.SetTypeSpecType(DeclSpec::TST_typedef, Loc, PrevSpec, TypeRep);
+    break;
+  }
+    
+  // builtin types
+  case tok::kw_short:
+    DS.SetTypeSpecWidth(DeclSpec::TSW_short, Loc, PrevSpec);
+    break;
+  case tok::kw_long:
+    DS.SetTypeSpecWidth(DeclSpec::TSW_long, Loc, PrevSpec);
+    break;
+  case tok::kw_signed:
+    DS.SetTypeSpecSign(DeclSpec::TSS_signed, Loc, PrevSpec);
+    break;
+  case tok::kw_unsigned:
+    DS.SetTypeSpecSign(DeclSpec::TSS_unsigned, Loc, PrevSpec);
+    break;
+  case tok::kw_void:
+    DS.SetTypeSpecType(DeclSpec::TST_void, Loc, PrevSpec);
+    break;
+  case tok::kw_char:
+    DS.SetTypeSpecType(DeclSpec::TST_char, Loc, PrevSpec);
+    break;
+  case tok::kw_int:
+    DS.SetTypeSpecType(DeclSpec::TST_int, Loc, PrevSpec);
+    break;
+  case tok::kw_float:
+    DS.SetTypeSpecType(DeclSpec::TST_float, Loc, PrevSpec);
+    break;
+  case tok::kw_double:
+    DS.SetTypeSpecType(DeclSpec::TST_double, Loc, PrevSpec);
+    break;
+  case tok::kw_wchar_t:
+    DS.SetTypeSpecType(DeclSpec::TST_wchar, Loc, PrevSpec);
+    break;
+  case tok::kw_bool:
+    DS.SetTypeSpecType(DeclSpec::TST_bool, Loc, PrevSpec);
+    break;
+  
+  // GNU typeof support.
+  case tok::kw_typeof:
+    ParseTypeofSpecifier(DS);
+    DS.Finish(Diags, PP.getSourceManager(), getLang());
+    return;
+  }
+  DS.SetRangeEnd(Tok.getLocation());
+  ConsumeToken();
+  DS.Finish(Diags, PP.getSourceManager(), getLang());
+}