[Parse] Add back TrailingSemiLoc to Expr, Stmt, and Decl

Author: rintaro

include/swift/AST/Decl.h

@@ -744,6 +744,8 @@ class alignas(1 << DeclAlignInBits) Decl {
   /// Returns the source range of the entire declaration.
   SourceRange getSourceRange() const;
 
+  SourceLoc TrailingSemiLoc;
+
   LLVM_ATTRIBUTE_DEPRECATED(
       void dump() const LLVM_ATTRIBUTE_USED,
       "only for use within the debugger");

include/swift/AST/Expr.h

@@ -500,6 +500,8 @@ class alignas(8) Expr {
   SourceLoc getLoc() const { return (SUBEXPR)->getLoc(); } \
   SourceRange getSourceRange() const { return (SUBEXPR)->getSourceRange(); }
 
+  SourceLoc TrailingSemiLoc;
+
   /// getSemanticsProvidingExpr - Find the smallest subexpression
   /// which obeys the property that evaluating it is exactly
   /// equivalent to evaluating this expression.

include/swift/AST/Stmt.h

@@ -78,6 +78,7 @@ class alignas(8) Stmt {
   SourceLoc getEndLoc() const;
 
   SourceRange getSourceRange() const;
+  SourceLoc TrailingSemiLoc;
 
   /// isImplicit - Determines whether this statement was implicitly-generated,
   /// rather than explicitly written in the AST.

lib/Parse/ParseDecl.cpp

@@ -2733,11 +2733,14 @@ static ParserStatus parseDeclItem(Parser &P,
       .fixItInsert(endOfPrevious, ";");
   }
 
-  ParserStatus Status = P.parseDecl(Options, handler);
-  if (Status.isError())
+  auto Result = P.parseDecl(Options, handler);
+  if (Result.isParseError())
     P.skipUntilDeclRBrace(tok::semi, tok::pound_endif);
-  PreviousHadSemi = P.consumeIf(tok::semi);
-  return Status;
+  SourceLoc SemiLoc;
+  PreviousHadSemi = P.consumeIf(tok::semi, SemiLoc);
+  if (PreviousHadSemi && Result.isNonNull())
+    Result.get()->TrailingSemiLoc = SemiLoc;
+  return Result;
 }
 
 /// \brief Parse the members in a struct/class/enum/protocol/extension.

lib/Parse/ParseStmt.cpp

@@ -297,17 +297,18 @@ ParserStatus Parser::parseBraceItems(SmallVectorImpl<ASTNode> &Entries,
     PreviousHadSemi = false;
     if (isStartOfDecl()
         && Tok.isNot(tok::pound_if, tok::pound_sourceLocation)) {
-      ParseDeclOptions options = IsTopLevel ? PD_AllowTopLevel : PD_Default;
-      ParserStatus Status =
-        parseDecl(options, [&](Decl *D) { TmpDecls.push_back(D); });
-      if (Status.isError()) {
+      ParserResult<Decl> DeclResult = 
+          parseDecl(IsTopLevel ? PD_AllowTopLevel : PD_Default,
+                    [&](Decl *D) {TmpDecls.push_back(D);});
+      if (DeclResult.isParseError()) {
         NeedParseErrorRecovery = true;
-        if (Status.hasCodeCompletion() && IsTopLevel &&
+        if (DeclResult.hasCodeCompletion() && IsTopLevel &&
             isCodeCompletionFirstPass()) {
           consumeDecl(BeginParserPosition, None, IsTopLevel);
-          return Status;
+          return DeclResult;
         }
       }
+      Result = DeclResult.getPtrOrNull();
 
       for (Decl *D : TmpDecls)
         Entries.push_back(D);
@@ -412,9 +413,16 @@ ParserStatus Parser::parseBraceItems(SmallVectorImpl<ASTNode> &Entries,
         Entries.push_back(Result);
     }
 
-    if (!NeedParseErrorRecovery && !PreviousHadSemi && Tok.is(tok::semi)) {
-      consumeToken();
+    if (!NeedParseErrorRecovery && Tok.is(tok::semi)) {
       PreviousHadSemi = true;
+      if (Expr *E = Result.dyn_cast<Expr*>())
+        E->TrailingSemiLoc = consumeToken(tok::semi);
+      else if (Stmt *S = Result.dyn_cast<Stmt*>())
+        S->TrailingSemiLoc = consumeToken(tok::semi);
+      else if (Decl *D = Result.dyn_cast<Decl*>())
+        D->TrailingSemiLoc = consumeToken(tok::semi);
+      else
+        assert(!Result && "Unsupported AST node");
     }
 
     if (NeedParseErrorRecovery) {