diff options
Diffstat (limited to 'sys/tools/sound/snd_fxdiv_gen.awk')
| -rw-r--r-- | sys/tools/sound/snd_fxdiv_gen.awk | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/sys/tools/sound/snd_fxdiv_gen.awk b/sys/tools/sound/snd_fxdiv_gen.awk new file mode 100644 index 0000000..5828062 --- /dev/null +++ b/sys/tools/sound/snd_fxdiv_gen.awk @@ -0,0 +1,142 @@ +#!/usr/bin/awk -f +# +# Copyright (c) 2008-2009 Ariff Abdullah <ariff@FreeBSD.org> +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +# SUCH DAMAGE. +# +# $FreeBSD$ +# + +function floor(x, r) +{ + r = int(x); + if (r > x) + r--; + return (r + 0); +} + +function shl(x, y) +{ + while (y > 0) { + x *= 2; + y--; + } + return (x); +} + +function shr(x, y) +{ + while (y > 0 && x != 0) { + x = floor(x / 2); + y--; + } + return (x); +} + +function calcdiv(r, x, y, z) +{ + y = floor(FXONE / x); + z = FXSHIFT; + + while (shr((y * x), z) < 1) + y++; + + while ((y % 2) == 0 && z > 0) { + y = floor(y / 2); + z--; + } + + r["mul"] = y; + r["shift"] = z; +} + +BEGIN { + FXSHIFT = 16; + FXONE = shl(1, FXSHIFT); + + SND_CHN_MAX = 18; + + PCM_8_BPS = 1; + PCM_16_BPS = 2; + PCM_24_BPS = 3; + PCM_32_BPS = 4; + + SND_MAX_ALIGN = SND_CHN_MAX * PCM_32_BPS; + + for (i = 1; i <= SND_CHN_MAX; i++) { + aligns[PCM_8_BPS * i] = 1; + aligns[PCM_16_BPS * i] = 1; + aligns[PCM_24_BPS * i] = 1; + aligns[PCM_32_BPS * i] = 1; + } + + printf("#ifndef _SND_FXDIV_GEN_H_\n"); + printf("#define _SND_FXDIV_GEN_H_\n\n"); + + printf("/*\n"); + printf(" * Generated using snd_fxdiv_gen.awk, heaven, wind and awesome.\n"); + printf(" *\n"); + printf(" * DO NOT EDIT!\n"); + printf(" */\n\n"); + printf("#ifdef SND_USE_FXDIV\n\n"); + + printf("/*\n"); + printf(" * Fast unsigned 32bit integer division and rounding, accurate for\n"); + printf(" * x = 1 - %d. This table should be enough to handle possible\n", FXONE); + printf(" * division for 1 - 72 (more can be generated though..).\n"); + printf(" *\n"); + printf(" * 72 = SND_CHN_MAX * PCM_32_BPS, which is why....\n"); + printf(" */\n\n"); + + printf("static const uint32_t snd_fxdiv_table[][2] = {\n"); + + for (i = 1; i <= SND_MAX_ALIGN; i++) { + if (aligns[i] != 1) + continue; + calcdiv(r, i); + printf("\t[0x%02x] = { 0x%04x, 0x%02x },", \ + i, r["mul"], r["shift"]); + printf("\t/* x / %-2d = (x * %-5d) >> %-2d */\n", \ + i, r["mul"], r["shift"]); + } + + printf("};\n\n"); + + printf("#define SND_FXDIV_MAX\t\t0x%08x\n", FXONE); + printf("#define SND_FXDIV(x, y)\t\t(((uint32_t)(x) *\t\t\t\\\n"); + printf("\t\t\t\t snd_fxdiv_table[y][0]) >>\t\t\\\n"); + printf("\t\t\t\t snd_fxdiv_table[y][1])\n"); + printf("#define SND_FXROUND(x, y)\t(SND_FXDIV(x, y) * (y))\n"); + printf("#define SND_FXMOD(x, y)\t\t((x) - SND_FXROUND(x, y))\n\n"); + + printf("#else\t/* !SND_USE_FXDIV */\n\n"); + + printf("#define SND_FXDIV_MAX\t\t0x%08x\n", 131072); + printf("#define SND_FXDIV(x, y)\t\t((x) / (y))\n"); + printf("#define SND_FXROUND(x, y)\t((x) - ((x) %% (y)))\n"); + printf("#define SND_FXMOD(x, y)\t\t((x) %% (y))\n\n"); + + printf("#endif\t/* SND_USE_FXDIV */\n\n"); + + printf("#endif\t/* !_SND_FXDIV_GEN_H_ */\n"); +} |
