📄 mad.h
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/* * mad - MPEG audio decoder * Copyright (C) 2000-2001 Robert Leslie * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * If you would like to negotiate alternate licensing terms, you may do * so by contacting the author: Robert Leslie <rob@mars.org> */# define SIZEOF_INT 4# define SIZEOF_LONG 4# define SIZEOF_LONG_LONG 8/* Id: version.h,v 1.16 2001/04/05 04:57:11 rob Exp */# ifndef LIBMAD_VERSION_H# define LIBMAD_VERSION_H# define MAD_VERSION_MAJOR 0# define MAD_VERSION_MINOR 13# define MAD_VERSION_PATCH 0# define MAD_VERSION_EXTRA " (beta)" // No tr# define MAD_VERSION_STRINGIZE(str) #str# define MAD_VERSION_STRING(num) MAD_VERSION_STRINGIZE(num)# define MAD_VERSION MAD_VERSION_STRING(MAD_VERSION_MAJOR) "." \ MAD_VERSION_STRING(MAD_VERSION_MINOR) "." \ MAD_VERSION_STRING(MAD_VERSION_PATCH) \ MAD_VERSION_EXTRA# define MAD_PUBLISHYEAR "2000-2001"# define MAD_AUTHOR "Robert Leslie" // No tr# define MAD_EMAIL "rob@mars.org"extern char const mad_version[];extern char const mad_copyright[];extern char const mad_author[];extern char const mad_build[];# endif/* Id: fixed.h,v 1.23 2001/04/05 04:57:11 rob Exp */# ifndef LIBMAD_FIXED_H# define LIBMAD_FIXED_H# if SIZEOF_INT >= 4typedef signed int mad_fixed_t;typedef signed int mad_fixed64hi_t;typedef unsigned int mad_fixed64lo_t;# elsetypedef signed long mad_fixed_t;typedef signed long mad_fixed64hi_t;typedef unsigned long mad_fixed64lo_t;# endif/* * Fixed-point format: 0xABBBBBBB * A == whole part (sign + 3 bits) * B == fractional part (28 bits) * * Values are signed two's complement, so the effective range is: * 0x80000000 to 0x7fffffff * -8.0 to +7.9999999962747097015380859375 * * The smallest representable value is: * 0x00000001 == 0.0000000037252902984619140625 (i.e. about 3.725e-9) * * 28 bits of fractional accuracy represent about * 8.6 digits of decimal accuracy. * * Fixed-point numbers can be added or subtracted as normal * integers, but multiplication requires shifting the 64-bit result * from 56 fractional bits back to 28 (and rounding.) * * Changing the definition of MAD_F_FRACBITS is only partially * supported, and must be done with care. */# define MAD_F_FRACBITS 28# if MAD_F_FRACBITS == 28# define MAD_F(x) ((mad_fixed_t) (x##L))# else# if MAD_F_FRACBITS < 28# warning "MAD_F_FRACBITS < 28"# define MAD_F(x) ((mad_fixed_t) \ (((x##L) + \ (1L << (28 - MAD_F_FRACBITS - 1))) >> \ (28 - MAD_F_FRACBITS)))# elif MAD_F_FRACBITS > 28# error "MAD_F_FRACBITS > 28 not currently supported"# define MAD_F(x) ((mad_fixed_t) \ ((x##L) << (MAD_F_FRACBITS - 28)))# endif# endif# define MAD_F_MIN ((mad_fixed_t) -0x80000000L)# define MAD_F_MAX ((mad_fixed_t) +0x7fffffffL)# define MAD_F_ONE MAD_F(0x10000000)# define mad_f_tofixed(x) ((mad_fixed_t) \ ((x) * (double) (1L << MAD_F_FRACBITS) + 0.5))# define mad_f_todouble(x) ((double) \ ((x) / (double) (1L << MAD_F_FRACBITS)))# define mad_f_intpart(x) ((x) >> MAD_F_FRACBITS)# define mad_f_fracpart(x) ((x) & ((1L << MAD_F_FRACBITS) - 1)) /* (x should be positive) */# define mad_f_fromint(x) ((x) << MAD_F_FRACBITS)# define mad_f_add(x, y) ((x) + (y))# define mad_f_sub(x, y) ((x) - (y))# if defined(FPM_64BIT)/* * This version should be the most accurate if 64-bit (long long) types are * supported by the compiler, although it may not be the most efficient. */# if defined(OPT_ACCURACY)# define mad_f_mul(x, y) \ ((mad_fixed_t) \ ((((signed long long) (x) * (y)) + \ (1L << (MAD_F_SCALEBITS - 1))) >> MAD_F_SCALEBITS))# else# define mad_f_mul(x, y) \ ((mad_fixed_t) (((signed long long) (x) * (y)) >> MAD_F_SCALEBITS))# endif# define MAD_F_SCALEBITS MAD_F_FRACBITS/* --- Intel --------------------------------------------------------------- */# elif defined(FPM_INTEL)/* * This Intel version is fast and accurate; the disposition of the least * significant bit depends on OPT_ACCURACY via mad_f_scale64(). */# define MAD_F_MLX(hi, lo, x, y) \ asm ("imull %3" \ : "=a" (lo), "=d" (hi) \ : "%a" (x), "rm" (y) \ : "cc")# if defined(OPT_ACCURACY)/* * This gives best accuracy but is not very fast. */# define MAD_F_MLA(hi, lo, x, y) \ ({ mad_fixed64hi_t __hi; \ mad_fixed64lo_t __lo; \ MAD_F_MLX(__hi, __lo, (x), (y)); \ asm ("addl %2,%0\n\t" \ "adcl %3,%1" \ : "=rm" (lo), "=rm" (hi) \ : "r" (__lo), "r" (__hi), "0" (lo), "1" (hi) \ : "cc"); \ })# endif /* OPT_ACCURACY */# if defined(OPT_ACCURACY)/* * Surprisingly, this is faster than SHRD followed by ADC. */# define mad_f_scale64(hi, lo) \ ({ mad_fixed64hi_t __hi_; \ mad_fixed64lo_t __lo_; \ mad_fixed_t __result; \ asm ("addl %4,%2\n\t" \ "adcl %5,%3" \ : "=rm" (__lo_), "=rm" (__hi_) \ : "0" (lo), "1" (hi), \ "ir" (1L << (MAD_F_SCALEBITS - 1)), "ir" (0) \ : "cc"); \ asm ("shrdl %3,%2,%1" \ : "=rm" (__result) \ : "0" (__lo_), "r" (__hi_), "I" (MAD_F_SCALEBITS) \ : "cc"); \ __result; \ })# else# define mad_f_scale64(hi, lo) \ ({ mad_fixed_t __result; \ asm ("shrdl %3,%2,%1" \ : "=rm" (__result) \ : "0" (lo), "r" (hi), "I" (MAD_F_SCALEBITS) \ : "cc"); \ __result; \ })# endif /* OPT_ACCURACY */# define MAD_F_SCALEBITS MAD_F_FRACBITS/* --- ARM ----------------------------------------------------------------- */# elif defined(FPM_ARM)/* * This ARM V4 version is as accurate as FPM_64BIT but much faster. The * least significant bit is properly rounded at no CPU cycle cost! */# if 1/* * There's a bug somewhere, possibly in the compiler, that sometimes makes * this necessary instead of the default implementation via MAD_F_MLX and * mad_f_scale64. It may be related to the use (or lack) of * -finline-functions and/or -fstrength-reduce. * * This is also apparently faster than MAD_F_MLX/mad_f_scale64. */# define mad_f_mul(x, y) \ ({ mad_fixed64hi_t __hi; \ mad_fixed64lo_t __lo; \ mad_fixed_t __result; \ asm ("smull %0, %1, %3, %4\n\t" \ "movs %0, %0, lsr %5\n\t" \ "adc %2, %0, %1, lsl %6" \ : "=&r" (__lo), "=&r" (__hi), "=r" (__result) \ : "%r" (x), "r" (y), \ "M" (MAD_F_SCALEBITS), "M" (32 - MAD_F_SCALEBITS) \ : "cc"); \ __result; \ })# endif# define MAD_F_MLX(hi, lo, x, y) \ asm ("smull %0, %1, %2, %3" \ : "=&r" (lo), "=&r" (hi) \ : "%r" (x), "r" (y))# define MAD_F_MLA(hi, lo, x, y) \ asm ("smlal %0, %1, %2, %3" \ : "+r" (lo), "+r" (hi) \ : "%r" (x), "r" (y))# define mad_f_scale64(hi, lo) \ ({ mad_fixed_t __result; \ asm ("movs %0, %1, lsr %3\n\t" \ "adc %0, %0, %2, lsl %4" \ : "=r" (__result) \ : "r" (lo), "r" (hi), \ "M" (MAD_F_SCALEBITS), "M" (32 - MAD_F_SCALEBITS) \ : "cc"); \ __result; \ })# define MAD_F_SCALEBITS MAD_F_FRACBITS/* --- MIPS ---------------------------------------------------------------- */# elif defined(FPM_MIPS)/* * This MIPS version is fast and accurate; the disposition of the least * significant bit depends on OPT_ACCURACY via mad_f_scale64(). */# define MAD_F_MLX(hi, lo, x, y) \ asm ("mult %2,%3" \ : "=l" (lo), "=h" (hi) \ : "%r" (x), "r" (y))# if defined(HAVE_MADD_ASM)# define MAD_F_MLA(hi, lo, x, y) \ asm ("madd %2,%3" \ : "+l" (lo), "+h" (hi) \ : "%r" (x), "r" (y))# elif defined(HAVE_MADD16_ASM)/* * This loses significant accuracy due to the 16-bit integer limit in the * multiply/accumulate instruction. */# define MAD_F_ML0(hi, lo, x, y) \ asm ("mult %2,%3" \ : "=l" (lo), "=h" (hi) \ : "%r" ((x) >> 12), "r" ((y) >> 16))# define MAD_F_MLA(hi, lo, x, y) \ asm ("madd16 %2,%3" \ : "+l" (lo), "+h" (hi) \ : "%r" ((x) >> 12), "r" ((y) >> 16))# define MAD_F_MLZ(hi, lo) ((mad_fixed_t) (lo))# endif# if defined(OPT_SPEED)# define mad_f_scale64(hi, lo) \ ((mad_fixed_t) ((hi) << (32 - MAD_F_SCALEBITS)))# define MAD_F_SCALEBITS MAD_F_FRACBITS# endif/* --- SPARC --------------------------------------------------------------- */# elif defined(FPM_SPARC)/* * This SPARC V8 version is fast and accurate; the disposition of the least * significant bit depends on OPT_ACCURACY via mad_f_scale64(). */# define MAD_F_MLX(hi, lo, x, y) \ asm ("smul %2, %3, %0\n\t" \ "rd %%y, %1" \ : "=r" (lo), "=r" (hi) \ : "%r" (x), "rI" (y))/* --- PowerPC ------------------------------------------------------------- */# elif defined(FPM_PPC)/* * This PowerPC version is tuned for the 4xx embedded processors. It is * effectively a tuned version of FPM_64BIT. It is a little faster and just * as accurate. The disposition of the least significant bit depends on * OPT_ACCURACY via mad_f_scale64(). */# define MAD_F_MLX(hi, lo, x, y) \ asm ("mulhw %1, %2, %3\n\t" \ "mullw %0, %2, %3" \ : "=&r" (lo), "=&r" (hi) \ : "%r" (x), "r" (y))# define MAD_F_MLA(hi, lo, x, y) \ ({ mad_fixed64hi_t __hi; \ mad_fixed64lo_t __lo; \ MAD_F_MLX(__hi, __lo, (x), (y)); \ asm ("addc %0, %2, %3\n\t" \ "adde %1, %4, %5" \ : "=r" (lo), "=r" (hi) \ : "%r" (__lo), "0" (lo), "%r" (__hi), "1" (hi)); \ })# if defined(OPT_ACCURACY)/* * This is accurate and ~2 - 2.5 times slower than the unrounded version. * * The __volatile__ improves the generated code by another 5% (fewer spills * to memory); eventually they should be removed. */# define mad_f_scale64(hi, lo) \ ({ mad_fixed_t __result; \ mad_fixed64hi_t __hi_; \ mad_fixed64lo_t __lo_; \ asm __volatile__ ("addc %0, %2, %4\n\t" \ "addze %1, %3" \ : "=r" (__lo_), "=r" (__hi_) \ : "r" (lo), "r" (hi), "r" (1 << (MAD_F_SCALEBITS - 1))); \ asm __volatile__ ("rlwinm %0, %2,32-%3,0,%3-1\n\t" \ "rlwimi %0, %1,32-%3,%3,31" \ : "=&r" (__result) \ : "r" (__lo_), "r" (__hi_), "I" (MAD_F_SCALEBITS)); \ __result; \ })# else# define mad_f_scale64(hi, lo) \ ({ mad_fixed_t __result; \ asm ("rlwinm %0, %2,32-%3,0,%3-1\n\t" \ "rlwimi %0, %1,32-%3,%3,31" \ : "=r" (__result) \ : "r" (lo), "r" (hi), "I" (MAD_F_SCALEBITS)); \ __result; \ })# endif /* OPT_ACCURACY */# define MAD_F_SCALEBITS MAD_F_FRACBITS/* --- Default ------------------------------------------------------------- */# elif defined(FPM_DEFAULT)/* * This version is the most portable but it loses significant accuracy. * Furthermore, accuracy is biased against the second argument, so care * should be taken when ordering operands. * * The scale factors are constant as this is not used with SSO. * * Pre-rounding is required to stay within the limits of compliance. */# define mad_f_mul(x, y) ((((x) + (1L << 11)) >> 12) * \ (((y) + (1L << 15)) >> 16))/* ------------------------------------------------------------------------- */# else# error "no FPM selected"# endif/* default implementations */# if !defined(mad_f_mul)# define mad_f_mul(x, y) \ ({ mad_fixed64hi_t __hi; \ mad_fixed64lo_t __lo; \ MAD_F_MLX(__hi, __lo, (x), (y)); \ mad_f_scale64(__hi, __lo); \ })# endif# if !defined(MAD_F_MLA)
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