Add semantic analysis for "blocks". 

Highlights...

- 4 new AST nodes, BlockExpr, BlockStmtExpr, BlockExprExpr, BlockDeclRefExpr.
- Sema::ActOnBlockStart(), ActOnBlockError(), ActOnBlockStmtExpr(), ActOnBlockExprExpr(), ActOnBlockReturnStmt().

Next steps...

- hack Sema::ActOnIdentifierExpr() to deal with block decl refs.
- add attribute handler for byref decls.
- add test cases.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@55710 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 1410f7e..1ab2220 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -282,6 +282,13 @@
     InitExprs.push_back(initexprs[i]);
 }
 
+/// getFunctionType - Return the underlying function type for this closure.
+///
+const FunctionType *BlockExpr::getFunctionType() const {
+  return getType()->getAsBlockPointerType()->
+                    getPointeeType()->getAsFunctionType();
+}
+
 //===----------------------------------------------------------------------===//
 // Generic Expression Routines
 //===----------------------------------------------------------------------===//
@@ -1432,3 +1439,18 @@
   return &SubExprs[0]+ARGS_START+getNumArgs();
 }
 
+// Blocks
+Stmt::child_iterator BlockStmtExpr::child_begin() {
+  return reinterpret_cast<Stmt**>(&Body);
+}
+Stmt::child_iterator BlockStmtExpr::child_end() {
+  return reinterpret_cast<Stmt**>(&Body)+1;
+}
+
+Stmt::child_iterator BlockExprExpr::child_begin() {
+  return reinterpret_cast<Stmt**>(&BodyExpr);
+}
+Stmt::child_iterator BlockExprExpr::child_end() {
+  return reinterpret_cast<Stmt**>(&BodyExpr)+1;
+}
+
diff --git a/lib/AST/StmtPrinter.cpp b/lib/AST/StmtPrinter.cpp
index a765060..f5806ea 100644
--- a/lib/AST/StmtPrinter.cpp
+++ b/lib/AST/StmtPrinter.cpp
@@ -874,6 +874,46 @@
   OS << "]";
 }
 
+void StmtPrinter::VisitBlockExpr(BlockExpr *Node) {
+  OS << "^";
+  
+  const FunctionType *AFT = Node->getFunctionType();
+  
+  if (isa<FunctionTypeNoProto>(AFT)) {
+    OS << "()";
+  } else if (!Node->arg_empty() || cast<FunctionTypeProto>(AFT)->isVariadic()) {
+    const FunctionTypeProto *FT = cast<FunctionTypeProto>(AFT);
+    OS << '(';
+    std::string ParamStr;
+    for (BlockStmtExpr::arg_iterator AI = Node->arg_begin(),
+         E = Node->arg_end(); AI != E; ++AI) {
+      if (AI != Node->arg_begin()) OS << ", ";
+      ParamStr = (*AI)->getName();
+      (*AI)->getType().getAsStringInternal(ParamStr);
+      OS << ParamStr;
+    }
+    
+    if (FT->isVariadic()) {
+      if (!Node->arg_empty()) OS << ", ";
+      OS << "...";
+    }
+    OS << ')';
+  }
+}
+
+void StmtPrinter::VisitBlockStmtExpr(BlockStmtExpr *Node) {
+  VisitBlockExpr(Node);
+  PrintRawCompoundStmt(Node->getBody());
+}
+
+void StmtPrinter::VisitBlockExprExpr(BlockExprExpr *Node) {
+  VisitBlockExpr(Node);
+  PrintExpr(Node->getExpr());
+}
+
+void StmtPrinter::VisitBlockDeclRefExpr(BlockDeclRefExpr *Node) {
+  OS << Node->getDecl()->getName();
+}
 //===----------------------------------------------------------------------===//
 // Stmt method implementations
 //===----------------------------------------------------------------------===//
diff --git a/lib/AST/StmtSerialization.cpp b/lib/AST/StmtSerialization.cpp
index 23879ee..5dbd3cd 100644
--- a/lib/AST/StmtSerialization.cpp
+++ b/lib/AST/StmtSerialization.cpp
@@ -1109,6 +1109,38 @@
 }
 
 //===----------------------------------------------------------------------===//
+//   Serialization for Clang Extensions.
+//===----------------------------------------------------------------------===//
+
+void BlockStmtExpr::EmitImpl(Serializer& S) const {
+  S.Emit(getType());
+  S.Emit(getCaretLocation());
+  S.EmitOwnedPtr(Body);
+}
+
+BlockStmtExpr* BlockStmtExpr::CreateImpl(Deserializer& D, ASTContext& C) {
+  QualType Q = QualType::ReadVal(D);
+  SourceLocation L = SourceLocation::ReadVal(D);
+  /*CompoundStmt* BodyStmt = cast<CompoundStmt>(*/D.ReadOwnedPtr<Stmt>(C)/*)*/;
+  assert(0 && "Cannot deserialize BlockBlockExpr yet");
+  // FIXME: need to handle parameters.
+  //return new BlockBlockExpr(L, Q, BodyStmt);
+  return 0;
+}
+
+void BlockDeclRefExpr::EmitImpl(Serializer& S) const {
+  S.Emit(Loc);
+  S.Emit(getType());
+  S.EmitBool(false);
+  S.EmitPtr(getDecl());
+}
+
+BlockDeclRefExpr* BlockDeclRefExpr::CreateImpl(Deserializer& D, ASTContext& C) {
+  assert(0 && "Cannot deserialize BlockDeclRefExpr yet");
+  return 0;
+}
+
+//===----------------------------------------------------------------------===//
 //   C++ Serialization
 //===----------------------------------------------------------------------===//
 void CXXDefaultArgExpr::EmitImpl(Serializer& S) const {