Implementation of Embarcadero array type traits

Patch authored by John Wiegley.

These are array type traits used for parsing code that employs certain
features of the Embarcadero C++ compiler: __array_rank(T) and
__array_extent(T, Dim).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130351 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index 1c4a942..8b9e5e7 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -490,6 +490,7 @@
 /// [C++]   'this'          [C++ 9.3.2]
 /// [G++]   unary-type-trait '(' type-id ')'
 /// [G++]   binary-type-trait '(' type-id ',' type-id ')'           [TODO]
+/// [EMBT]  array-type-trait '(' type-id ',' integer ')'
 /// [clang] '^' block-literal
 ///
 ///       constant: [C99 6.4.4]
@@ -571,6 +572,10 @@
 ///                   '__is_convertible'
 ///                   '__is_same'
 ///
+/// [Embarcadero] array-type-trait:
+///                   '__array_rank'
+///                   '__array_extent'
+///
 /// [Embarcadero] expression-trait:
 ///                   '__is_lvalue_expr'
 ///                   '__is_rvalue_expr'
@@ -1072,6 +1077,10 @@
   case tok::kw___is_convertible_to:
     return ParseBinaryTypeTrait();
 
+  case tok::kw___array_rank:
+  case tok::kw___array_extent:
+    return ParseArrayTypeTrait();
+
   case tok::kw___is_lvalue_expr:
   case tok::kw___is_rvalue_expr:
     return ParseExpressionTrait();
diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index aade050..5075205 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -1970,6 +1970,14 @@
   }
 }
 
+static ArrayTypeTrait ArrayTypeTraitFromTokKind(tok::TokenKind kind) {
+  switch(kind) {
+  default: llvm_unreachable("Not a known binary type trait");
+  case tok::kw___array_rank:                 return ATT_ArrayRank;
+  case tok::kw___array_extent:               return ATT_ArrayExtent;
+  }
+}
+
 static ExpressionTrait ExpressionTraitFromTokKind(tok::TokenKind kind) {
   switch(kind) {
   default: assert(false && "Not a known unary expression trait.");
@@ -2043,6 +2051,50 @@
   return Actions.ActOnBinaryTypeTrait(BTT, Loc, LhsTy.get(), RhsTy.get(), RParen);
 }
 
+/// ParseArrayTypeTrait - Parse the built-in array type-trait
+/// pseudo-functions.
+///
+///       primary-expression:
+/// [Embarcadero]     '__array_rank' '(' type-id ')'
+/// [Embarcadero]     '__array_extent' '(' type-id ',' expression ')'
+///
+ExprResult Parser::ParseArrayTypeTrait() {
+  ArrayTypeTrait ATT = ArrayTypeTraitFromTokKind(Tok.getKind());
+  SourceLocation Loc = ConsumeToken();
+
+  SourceLocation LParen = Tok.getLocation();
+  if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen))
+    return ExprError();
+
+  TypeResult Ty = ParseTypeName();
+  if (Ty.isInvalid()) {
+    SkipUntil(tok::comma);
+    SkipUntil(tok::r_paren);
+    return ExprError();
+  }
+
+  switch (ATT) {
+  case ATT_ArrayRank: {
+    SourceLocation RParen = MatchRHSPunctuation(tok::r_paren, LParen);
+    return Actions.ActOnArrayTypeTrait(ATT, Loc, Ty.get(), NULL, RParen);
+  }
+  case ATT_ArrayExtent: {
+    if (ExpectAndConsume(tok::comma, diag::err_expected_comma)) {
+      SkipUntil(tok::r_paren);
+      return ExprError();
+    }
+
+    ExprResult DimExpr = ParseExpression();
+    SourceLocation RParen = MatchRHSPunctuation(tok::r_paren, LParen);
+
+    return Actions.ActOnArrayTypeTrait(ATT, Loc, Ty.get(), DimExpr.get(), RParen);
+  }
+  default:
+    break;
+  }
+  return ExprError();
+}
+
 /// ParseExpressionTrait - Parse built-in expression-trait
 /// pseudo-functions like __is_lvalue_expr( xxx ).
 ///