Emulation/mupen64plus-rsp-cxd4
1
0
Fork 0
mirror of https://github.com/mupen64plus/mupen64plus-rsp-cxd4.git synced 2025-04-02 10:51:55 -04:00
Code Issues Projects Releases Packages Wiki Activity

Conker's BFD micro-optimization with 2's cmpl. integer division

Browse source
This commit is contained in:
unknown 2015-06-08 16:28:21 -04:00
parent 690bb76c47
commit bf7c98f586
1 changed files with 7 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
vu/divide.c
View file

@ -1070,10 +1070,17 @@ INLINE static void do_div(i32 data, int sqrt, int precision)
int fetch;
int shift;
#if (~0 >> 1 == -1)
data ^= (s32)(data + 32768) >> 31; /* DP only: (data < -32768) */
fetch = (s32)(data + 0) >> 31;
data ^= fetch;
data -= fetch; /* two's complement: -x == ~x - (~0) on wrap-around */
#else
if (precision == SP_DIV_PRECISION_SINGLE)
data = (data < 0) ? -data : +data;
if (precision == SP_DIV_PRECISION_DOUBLE && data < 0)
data = (data >= -32768) ? -data : ~data;
#endif
/*
* Note, from the code just above, that data cannot be negative.