This is not really necessary since it can share area with ROM.
Performance impact should be very minimal (haven't noticed it myself)
and could be compensated (even by a positive offset) if we bump the ROM
cache area size.
Tested with several dynarecs.
This removes libco and all the usages of it (+pthreads).
Rewired all dynarecs and interpreter to return after every frame so that
libretro can process events. This required to make dynarec re-entrant.
Dynarecs were updated to check for new frame on every update (IRQ, cycle
exhaustion, I/O write, etc). The performance impact of doing so should
be minimal (and definitely outweight the libco gains). While at it,
fixed small issues to get a bit more perf: arm dynarec was not idling
correctly, mips was using stack when not needed, etc.
Tested on PSP (mips), OGA (armv7), Linux (x86 and interpreter). Not
tested on Android though.
- Removing RETRO_SYSTEM_MEMORY from retro_get_memory_data/size
since its incompatible for 2 reasons:
1. gba uses at least 2 blocks of memory, which is not supported
2. the way gpsp's memory block are not contiguous (see memory
descriptors)
- Adds core option to allow battery saves using the libretro api
(retro_get_memory_data/size)
- Initial save size set at 128KB and actual size is automatically
determined internally by gba.
- This will always assume that a save file is supported since save
size or type cannot be determined until gba tries to write to backup memory.
- A 128KB block of memory is used as buffer, similar method to VBA
Next/Beetle GBA workarounds.
Fix https://github.com/libretro/gpsp/issues/72
Similar fix to https://github.com/libretro/pcsx_rearmed/pull/390. The
Nintendo svcBackdoor can cause stack corruption if an interrupt
happens during it, this uses Luma3DS/Rosalina's svcCustomBackdoor instead.