Autoglobal CVs without silence -- Summary

Okay, rewind and reset time. Dmitry, here's a quick summary of what's being done, how, and why. Initial Problem: PHP6 needs better http input encoding detection, preferably with minimal wasted effort in conversion and limited vectors for conversion failure based attacks. Proposed Solution: Wait until the first time a given input argument is requested before actually converting it. This allows scripts to perform their own (potentially more relevant) determination of what the correct input encoding is. Proposed Implementation for this solution: Make JIT be runtime based and fine-grained enough to signal not just the autoglobal being fetched, but what specific dimension/property within that auto global is being requested. Using runtime-dimension-JIT to decode input arguments as they are requested. Rejected Implementation: Use object/array-access overloading to JIT the values instead. While this solution is the simplest and can be done with relatively few LOCs, it breaks assumptions about the GPC auto globals (is_array() fails, is_object() succeeds, assignments of the autoglobals becomes "reference-like"*). In short, this solution introduces BC issues. ---------------------------------------------------------------- Next Problem: How to actually make runtime-JIT with dim/prop level granularity? Proposed Solution: Catch fetches during FETCH_DIM/FETCH_OBJ execution handlers. ---------------------------------------------------------------- Next Problem: auto_globals aren't processed as CVs, meaning that during FETCH_DIM, there's no way to tell if op1 came from an auto global or not (since the fetch happened earlier). Solution (Implemented last week): Remove restriction on CVing auto globals by adding a fetch_type field to auto global structure. ---------------------------------------------------------------- Next Problem: Silence operator forces non-CV even in situations where a CV is appropriate since the associated fetch_dim/obj op would not fall outside of silence scoping. Proposed Solution (patch from prior email): modify the variable parsing routines slightly to rewrite simple fetch ops to CV'd fetch_dim/obj ops when appropriate. ---------------------------------------------------------------- I'm not meaning to apply pressure (a week doesn't effect my timetable any), I can even move-forward with the next (and last) ZE related patch (FETCH_DIM/FETCH_OBJ handling) separate from this one. I'm just trying to balance Andrei's timetable on one side, with a desired to not overwhelm you and Andi with ZE patches on the other. Hopefully this summary helps everyone get on the same page. -Sara * - Sidenote: I refuse to call object behavior "reference by default", I've had too many people notice that it's not actually true and expect me to explain why in 2 minutes without the aid of a whiteboard.in