Mercurial > hg > index.fcgi > lj > lj046-2players
annotate src/gba_asm.s @ 0:c84446dfb3f5
initial add
author | paulo@localhost |
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date | Fri, 13 Mar 2009 00:39:12 -0700 |
parents | |
children |
rev | line source |
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paulo@0 | 1 @ fixed fastfmul(fixed x, fixed y) |
paulo@0 | 2 @ Multiply two 16.16 fixed-point numbers. |
paulo@0 | 3 |
paulo@0 | 4 .ARM |
paulo@0 | 5 .ALIGN |
paulo@0 | 6 .GLOBL fastfmul |
paulo@0 | 7 |
paulo@0 | 8 fastfmul: |
paulo@0 | 9 smull r1,r2,r0,r1 |
paulo@0 | 10 mov r0,r2,LSL#16 |
paulo@0 | 11 orr r0,r0,r1,LSR#16 |
paulo@0 | 12 bx lr |
paulo@0 | 13 |
paulo@0 | 14 |
paulo@0 | 15 @ int dv(int num, int den) |
paulo@0 | 16 @ Divide two signed integers. |
paulo@0 | 17 |
paulo@0 | 18 .THUMB |
paulo@0 | 19 .THUMB_FUNC |
paulo@0 | 20 .ALIGN |
paulo@0 | 21 .GLOBL dv |
paulo@0 | 22 |
paulo@0 | 23 dv: |
paulo@0 | 24 cmp r1, #0 |
paulo@0 | 25 beq 0f |
paulo@0 | 26 swi 6 |
paulo@0 | 27 bx lr |
paulo@0 | 28 0: |
paulo@0 | 29 ldr r0, =0x7fffffff |
paulo@0 | 30 bx lr |
paulo@0 | 31 |
paulo@0 | 32 |
paulo@0 | 33 @ int fracmul(signed int x, signed int frac) |
paulo@0 | 34 @ Multiply by a 0.32 fractional number between -0.5 and 0.5. |
paulo@0 | 35 @ Used for fast division by a constant. |
paulo@0 | 36 |
paulo@0 | 37 .ARM |
paulo@0 | 38 .ALIGN |
paulo@0 | 39 .GLOBL fracmul |
paulo@0 | 40 |
paulo@0 | 41 fracmul: |
paulo@0 | 42 smull r1,r2,r0,r1 |
paulo@0 | 43 mov r0, r2 |
paulo@0 | 44 bx lr |
paulo@0 | 45 |
paulo@0 | 46 |
paulo@0 | 47 @ int fracumul(unsigned int x, unsigned int frac) |
paulo@0 | 48 @ Multiply by a 0.32 fractional number between 0 and 1. |
paulo@0 | 49 @ Used for fast division by a constant. |
paulo@0 | 50 |
paulo@0 | 51 .ARM |
paulo@0 | 52 .ALIGN |
paulo@0 | 53 .GLOBL fracumul |
paulo@0 | 54 |
paulo@0 | 55 fracumul: |
paulo@0 | 56 umull r1,r2,r0,r1 |
paulo@0 | 57 mov r0, r2 |
paulo@0 | 58 bx lr |
paulo@0 | 59 |
paulo@0 | 60 |
paulo@0 | 61 @ void gblz_unpack(const void *src, void *dst) |
paulo@0 | 62 @ Unpack GB LZSS format data. |
paulo@0 | 63 |
paulo@0 | 64 .THUMB |
paulo@0 | 65 .THUMB_FUNC |
paulo@0 | 66 .ALIGN |
paulo@0 | 67 .GLOBL _gblz_unpack |
paulo@0 | 68 |
paulo@0 | 69 _gblz_unpack: |
paulo@0 | 70 swi 0x11 @ LZ77UnCompWRAM |
paulo@0 | 71 bx lr |
paulo@0 | 72 |
paulo@0 | 73 |