Same thing but allows both GeckoCode and Code to be utilized directly
without predicates for equality/inequality in stardard algorithms
The size check for std::vectors is unnecessary, as this is built into std::vector's operator==
Because of the way this works, randomly overwriting the handler
when loading a savestate will break things because of the
self-modifying nature of the handler.
Dolphin emulates GeckoCodes by fiddling with the CPU state when a
VI Interrupt occurs. The problem with this is that we don't know
where the PC is so it's non-deterministic and not necessarily
suitable for use with the codehandler.
There are two options: Patch the game like Gecko OS either directly
or using HLE::Patch, or use a trampoline so we can branch from any
PC even if it would otherwise not be valid. The problem with Gecko OS
patches is there are 10 of them and they have to be configured
manually (i.e. Game INIs to would need to have a [Core]GeckoHookType
property).
HLE_Misc::GeckoReturnTrampoline enables the Code Handler to be
entered from anywhere, the trampoline restores all the registers that
had to be secretly saved to the stack.
Turns out one of the magic numbers was very magic. The gameid is
an ad-hoc comm protocol with HLE_Misc to control the number of times
the ICache is reset.
The active codes vector cannot safely be used outside the mutex,
move the lock out into RunCodeHandler. s_code_handler_installed was
also racing against SetActiveCodes since it's being written both
inside and outside the lock.
General cleanup. Add s_ prefixes, use constexpr, remove C casts.
Replaces them with forward declarations of used types, or removes them entirely if they aren't used at all. This also replaces certain Common headers with less inclusive ones (in terms of definitions they pull in).
