2016-02-07

Cen64 Git (2016/02/07)

EmuCR: Cen64Cen64 Git (2016/02/07) is compiled. Cen64 is a Cycle-Accurate Nintendo 64 Simulator.

Cen64 Git Changelog:
* Improved SSE2 vector shuffle patch from izy.
* More optimization patches from izy.
izy noticed that the branch LUT was generating memory moves
and could be replaced with an inlined function that coerces
gcc into generating a lea in its place:
4005ac: 8d 1c 00 lea (%rax,%rax,1),%ebx
4005af: c1 fb 1f sar $0x1f,%ebx
4005b2: f7 d3 not %ebx
(no memory access)
4005b9: c1 e8 1e shr $0x1e,%eax
4005bc: 83 e0 01 and $0x1,%eax
4005bf: 44 8b 24 85 90 07 40 mov 0x400790(,%rax,4),%r12d
(original has memory access)
This ends up optimizing branch instructions quite nicely:
"You see that when you use "mask" you execute "~mask". The
compiler understands that ~(~(partial_mask)) = partial_mask
and removes both "NOTs". So in this case my version uses 2
instructions and no memory access/cache pollution."

Download: Cen64 Git (2016/02/07)
Source: Here

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