Mercurial > hg > index.fcgi > lj > lj046

comparison src/gba_asm.s @ 0:c84446dfb3f5

find changesets by author, revision, files, or words in the commit message
initial add
author paulo@localhost
date Fri, 13 Mar 2009 00:39:12 -0700
parents
children
comparison
equal deleted inserted replaced
-1:000000000000 0:2fd121800716
1 @ fixed fastfmul(fixed x, fixed y)
2 @ Multiply two 16.16 fixed-point numbers.
3
4 .ARM
5 .ALIGN
6 .GLOBL fastfmul
7
8 fastfmul:
9 smull r1,r2,r0,r1
10 mov r0,r2,LSL#16
11 orr r0,r0,r1,LSR#16
12 bx lr
13
14
15 @ int dv(int num, int den)
16 @ Divide two signed integers.
17
18 .THUMB
19 .THUMB_FUNC
20 .ALIGN
21 .GLOBL dv
22
23 dv:
24 cmp r1, #0
25 beq 0f
26 swi 6
27 bx lr
28 0:
29 ldr r0, =0x7fffffff
30 bx lr
31
32
33 @ int fracmul(signed int x, signed int frac)
34 @ Multiply by a 0.32 fractional number between -0.5 and 0.5.
35 @ Used for fast division by a constant.
36
37 .ARM
38 .ALIGN
39 .GLOBL fracmul
40
41 fracmul:
42 smull r1,r2,r0,r1
43 mov r0, r2
44 bx lr
45
46
47 @ int fracumul(unsigned int x, unsigned int frac)
48 @ Multiply by a 0.32 fractional number between 0 and 1.
49 @ Used for fast division by a constant.
50
51 .ARM
52 .ALIGN
53 .GLOBL fracumul
54
55 fracumul:
56 umull r1,r2,r0,r1
57 mov r0, r2
58 bx lr
59
60
61 @ void gblz_unpack(const void *src, void *dst)
62 @ Unpack GB LZSS format data.
63
64 .THUMB
65 .THUMB_FUNC
66 .ALIGN
67 .GLOBL _gblz_unpack
68
69 _gblz_unpack:
70 swi 0x11 @ LZ77UnCompWRAM
71 bx lr
72
73