3887 - clean up early exits in interpreter loop

It's always confusing when `break` refers to a `switch` but `continue`
refers to the loop around the `switch`. But we've done ugly things like
this and `goto` for expedience. However, we're starting to run into cases
where we now need to insert code at every `continue` or `continue`-mimicking
`goto` inside the core interpreter loop. Better to make the loop single-entry-single-exit.
Common things to run after every instruction will now happen inside the
`finish_instruction` function rather than at the `finish_instruction` label.

1 files changed, 6 insertions, 2 deletions

diff --git a/071recipe.cc b/071recipe.cc
index 1a145ed6..c44d3127 100644
--- a/071recipe.cc
+++ b/071recipe.cc
@@ -114,13 +114,17 @@ case CALL: {
     raise << maybe(current_recipe_name()) << "tried to call empty recipe in '" << to_string(current_instruction()) << "'" << end();
     break;
   }
-  instruction/*copy*/ call_instruction = current_instruction();
+  const call& caller_frame = current_call();
+  instruction/*copy*/ call_instruction = to_instruction(caller_frame);
   call_instruction.operation = ingredients.at(0).at(0);
   call_instruction.ingredients.erase(call_instruction.ingredients.begin());
   Current_routine->calls.push_front(call(ingredients.at(0).at(0)));
   ingredients.erase(ingredients.begin());  // drop the callee
   finish_call_housekeeping(call_instruction, ingredients);
-  continue;
+  // not done with caller
+  write_products = false;
+  fall_through_to_next_instruction = false;
+  break;
 }
 
 //:: check types for 'call' instructions