This moves all the byte swapping utilities into a header named Swap.h.
A dedicated header is much more preferable here due to the size of the
code itself. In general usage throughout the codebase, CommonFuncs.h was
generally only included for these functions anyway. These being in their
own header avoids dumping the lesser used utilities into scope. As well
as providing a localized area for more utilities related to byte
swapping in the future (should they be needed). This also makes it nicer
to identify which files depend on the byte swapping utilities in
particular.
Since this is a completely new header, moving the code uncovered a few
indirect includes, as well as making some other inclusions unnecessary.
TryReadInstruction doesn't validate the address it resolves, that
can result in Memory::GetPointer failing and returning nullptr
which then leads to a nullptr dereference and a crash.
Created PowerPC::HostIsInstructionRAMAddress which works the same
way as PowerPC::HostIsRAMAddress for the IBAT.
It was apparently causing heavy slowdowns on game even though it wouldn't spam much, probably caused by the amount of additional check caused by the logs levels changes.
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.
The active codes normally get cleared when a game boots, because
LoadPatches gets called, replacing the codes from the previous game.
However, there were cases where LoadPatches doesn't get called, and
then codes from the previous game would be used for the current game.
This commit clears the codes on shutdown so that it doesn't matter
whether the boot process loads LoadPatches.
ISOProperties loads codes using ActionReplay::LoadCodes which actually applies
the codes to the global state. If a game is running then that games receives
all the codes (and ACTIVE status) from the second game being shown in
ISOProperties which is not desirable.
The PowerPC CPU has bits in MSR (DR and IR) which control whether
addresses are translated. We should respect these instead of mixing
physical addresses and translated addresses into the same address space.
This is mostly mass-renaming calls to memory accesses APIs from places
which expect address translation to use a different version from those
which do not expect address translation.
This does very little on its own, but it's the first step to a correct BAT
implementation.
