A start on allowing non-local control flow, for exceptions, try-finally, and ...

src/jump-target.h

Index: src/jump-target.h
===================================================================
--- src/jump-target.h	(revision 3310)
+++ src/jump-target.h	(working copy)
@@ -184,7 +184,15 @@
 // and will drop state from nested statements as part of merging.
 //
 // Break targets are used for return, break, and continue targets.
+//
+// The fast compiler needs a similar object, containing a Label and
+// the stack height.  Since the parser already creates break targets
+// at all the appropriate sites, and creates the necessary links from
+// the AST to the break targets, we add an interface to break targets that
+// simply exposes the stack height and their underlying label, for use
+// in the fast compiler.
 
+
 class BreakTarget : public JumpTarget {
  public:
   // Construct a break target.
@@ -222,6 +230,9 @@
   // Setter for expected height.
   void set_expected_height(int expected) { expected_height_ = expected; }
 
+  // Added interface for the fast compiler:
+  int expected_height() { return expected_height_; }
+  // Label* entry_label() is already declared public in JumpTarget.
  private:
   // The expected height of the expression stack where the target will
   // be bound, statically known at initialization time.