Simplfy handling of exits from scoped blocks.

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index abd06591c4057e6c91e130ccee7f7d43821544da..4371093e8669768686fd80418b886b35f6fa4494 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -1587,19 +1587,11 @@ Block* Parser::ParseScopedBlock(ZoneStringList* labels, bool* ok) {
   body->set_block_scope(block_scope);
 
   if (block_scope != NULL) {
-    // Create exit block.
-    Block* exit = new(zone()) Block(isolate(), NULL, 1, false);
+    // Rewrite the block { B } to a block: { { B } ExitContext; }
+    Block* exit = new(zone()) Block(isolate(), NULL, 2, false);
+    exit->AddStatement(body);
     exit->AddStatement(new(zone()) ExitContextStatement());

[Kevin Millikin (Chromium), 2011/09/02 15:17:44]

Now we're no longer making essential use of ExitContextStatement (it's
completely predictable where it will occur).

As a next change, can you get rid of it?  'With' already makes do without it by
compiling the code implicitly at the end of the body.  Catch and blocks with
scopes could do the same.

[Steven, 2011/09/05 08:54:50]

Will do it.
On 2011/09/02 15:17:44, Kevin Millikin wrote:

-
-    // Create a try-finally statement.
-    TryFinallyStatement* try_finally =
-        new(zone()) TryFinallyStatement(body, exit);
-    try_finally->set_escaping_targets(collector.targets());
-
-    // Create a result block.
-    Block* result = new(zone()) Block(isolate(), NULL, 1, false);
-    result->AddStatement(try_finally);
-    return result;
+    return exit;
   } else {
     return body;
   }