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EmuCR: higanhigan v106r76 is released. higan (formerly bsnes) is a Nintendo multi-system emulator that began development on 2004-10-14. It currently supports the following systems:
- Famicom
- Super Famicom
- Game Boy
- Game Boy Color
- Game Boy Advance

higan also supports the following subsystems:
- Super Game Boy
- BS-X Satellaview
- Sufami Turbo

higan Changelog:
* Update to v106r76 release.

byuu says:

I added some useful new functions to nall/primitives:

auto Natural::integer() const -> Integer;
auto Integer::natural() const -> Natural;

These let you cast between signed and unsigned representation without
having to care about the value of T (eg if you take a Natural as a
template parameter.) So for instance when you're given an unsigned type
but it's supposed to be a sign-extended type (example: signed
multiplication), eg Natural → Integer, you can just say:

x = y.integer() * z.integer();

The TLCS900H core gained some more pesky instructions such as DAA, BS1F,

I stole an optimization from RACE for calculating the overflow flag on
addition. Assuming: z = x + y + c;

Before: ~(x ^ y) & (x ^ z) & signBit;
After: (x ^ z) & (y ^ z) & signBit;

Subtraction stays the same. Assuming: z = x - y - c;

Same: (x ^ y) & (x ^ z) & signBit;

However, taking a speed penalty, I've implemented the carry computation
in a way that doesn't require an extra bit.

Adding before:

uint9 z = x + y + c;
c = z & 0x100;

Subtracting before:

uint9 z = x - y - c;
c = z & 0x100;

Adding after:

uint8 z = x + y + c;
c = z < x || z == x && c; Subtracting after: uint8 z = x - y - c; c = z > x || z == x && c;

I haven't been able to code golf the new carry computation to be any
shorter, unless I include an extra bit, eg for adding:

c = z < x + c; But that defeats the entire point of the change. I want the computation to work even when T is uintmax_t. If anyone can come up with a faster method, please let me know. Anyway ... I also had to split off INC and DEC because they compute flags differently (word and long modes don't set flags at all, byte mode doesn't set carry at all.) I also added division by zero support, although I don't know if it's actually hardware accurate. It's what other emulators do, though. Download: higan v106r76 x64
Source: Here

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