byuu says:
Changelog:
- added 30 new PAL games to icarus (courtesy of Mikerochip)
- new version of libco no longer requires mprotect nor W|X permissions
- nall: default C compiler to -std=c11 instead of -std=c99
- nall: use `-fno-strict-aliasing` during compilation
- updated nall/certificates (hopefully for the last time)
- updated nall/http to newer coding conventions
- nall: improve handling of range() function
I didn't really work on higan at all, this is mostly just a release
because lots of other things have changed.
The most interesting is `-fno-strict-aliasing` ... basically, it joins
`-fwrapv` as being "stop the GCC developers from doing *really* evil
shit that could lead to security vulnerabilities or instabilities."
For the most part, it's a ~2% speed penalty for higan. Except for the
Sega Genesis, where it's a ~10% speedup. I have no idea how that's
possible, but clearly something's going very wrong with strict aliasing
on the Genesis core.
So ... it is what it is. If you need the performance for the non-Genesis
cores, you can turn it off in your builds. But I'm getting quite sick of
C++'s "surprises" and clever compiler developers, so I'm keeping it on
in all of my software going forward.
byuu says:
Changelog:
- rewrote the Z80 core to properly handle 0xDD (IX0 and 0xFD (IY)
prefixes
- added Processor::Z80::Bus as a new type of abstraction
- all of the instructions implemented have their proper T-cycle counts
now
- added nall/certificates for my public keys
The goal of `Processor::Z80::Bus` is to simulate the opcode fetches being
2-read + 2-wait states; operand+regular reads/writes being 3-read. For
now, this puts the cycle counts inside the CPU core. At the moment, I
can't think of any CPU core where this wouldn't be appropriate. But it's
certainly possible that such a case exists. So this may not be the
perfect solution.
The reason for having it be a subclass of Processor::Z80 instead of
virtual functions for the MasterSystem::CPU core to define is due to
naming conflicts. I wanted the core to say `in(addr)` and have it take
the four clocks. But I also wanted a version of the function that didn't
consume time when called. One way to do that would be for the core to
call `Z80::in(addr)`, which then calls the regular `in(addr)` that goes to
`MasterSystem::CPU::in(addr)`. But I don't want to put the `Z80::`
prefix on all of the opcodes. Very easy to forget it, and then end up not
consuming any time. Another is to use uglier names in the
`MasterSystem::CPU` core, like `read_`, `write_`, `in_`, `out_`, etc. But,
yuck.
So ... yeah, this is an experiment. We'll see how it goes.
Tim Allen