/*
* libmad - MPEG audio decoder library
* Copyright (C) 2000-2004 Underbit Technologies, Inc.
*
* 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
*
* $Id: fixed.h,v 1.38 2004/02/17 02:02:03 rob Exp $
*/
#ifndef LIBMAD_FIXED_H
#define LIBMAD_FIXED_H
#include "config.h"
#if SIZEOF_INT >= 4
typedef signed int mad_fixed_t;
typedef signed int mad_fixed64hi_t;
typedef unsigned int mad_fixed64lo_t;
#else
typedef signed long mad_fixed_t;
typedef signed long mad_fixed64hi_t;
typedef unsigned long mad_fixed64lo_t;
#endif
#if defined(_MSC_VER)
#define mad_fixed64_t signed __int64
#elif 1 || defined(__GNUC__)
#define mad_fixed64_t signed long long
#endif
#if defined(FPM_FLOAT)
typedef double mad_sample_t;
#else
typedef mad_fixed_t mad_sample_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_FLOAT)
#error "FPM_FLOAT not yet supported"
#undef MAD_F
#define MAD_F(x) mad_f_todouble(x)
#define mad_f_mul(x, y) ((x) * (y))
#define mad_f_scale64
#undef ASO_ZEROCHECK
#elif defined(FPM_64BIT)
/*
* This version should be the most accurate if 64-bit 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)((((mad_fixed64_t)(x) * (y)) + \
(1L << (MAD_F_SCALEBITS - 1))) >> \
MAD_F_SCALEBITS))
#else
#define mad_f_mul(x, y) \
((mad_fixed_t)(((mad_fixed64_t)(x) * (y)) >> MAD_F_SCALEBITS))
#endif
#define MAD_F_SCALEBITS MAD_F_FRACBITS
/* --- Intel --------------------------------------------------------------- */
#elif defined(FPM_INTEL)
#if defined(_MSC_VER)
#pragma warning(push)
#pragma warning(disable : 4035) /* no return value */
static __forceinline mad_fixed_t mad_f_mul_inline(mad_fixed_t x, mad_fixed_t y)
{
enum
{
fracbits = MAD_F_FRACBITS
};
__asm {
mov eax, x
imul y
shrd eax, edx, fracbits
}
/* implicit return of eax */
}
#pragma warning(pop)
#define mad_f_mul mad_f_mul_inline
#define mad_f_scale64
#else
/*
* 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; \
})
#elif defined(OPT_INTEL)
/*
* Alternate Intel scaling that may or may not perform better.
*/
#define mad_f_scale64(hi, lo) \
({ \
mad_fixed_t __result; \
asm("shrl %3,%1\n\t" \
"shll %4,%2\n\t" \
"orl %2,%1" \
: "=rm"(__result) \
: "0"(lo), "r"(hi), \
"I"(MAD_F_SCALEBITS), "I"(32 - 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
#endif
/* --- 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
/*
* This is faster than the default implementation via MAD_F_MLX() and
* 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_MLN(hi, lo) \
asm("rsbs %0, %2, #0\n\t" \
"rsc %1, %3, #0" \
: "=r"(lo), "=r"(hi) \
: "0"(lo), "1"(hi) \
: "cc")
#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 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) \
do \
{ \
asm("mullw %0,%1,%2" \
: "=r"(lo) \
: "%r"(x), "r"(y)); \
asm("mulhw %0,%1,%2" \
: "=r"(hi) \
: "%r"(x), "r"(y)); \
} while (0)
#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("addc %0,%2,%3\n\t" \
"adde %1,%4,%5" \
: "=r"(lo), "=r"(hi) \
: "%r"(lo), "r"(__lo), \
"%r"(hi), "r"(__hi) \
: "xer"); \
})
#endif
#if defined(OPT_ACCURACY)
/*
* This is slower than the truncating version below it.
*/
#define mad_f_scale64(hi, lo) \
({ \
mad_fixed_t __result, __round; \
asm("rotrwi %0,%1,%2" \
: "=r"(__result) \
: "r"(lo), "i"(MAD_F_SCALEBITS)); \
asm("extrwi %0,%1,1,0" \
: "=r"(__round) \
: "r"(__result)); \
asm("insrwi %0,%1,%2,0" \
: "+r"(__result) \
: "r"(hi), "i"(MAD_F_SCALEBITS)); \
asm("add %0,%1,%2" \
: "=r"(__result) \
: "%r"(__result), "r"(__round)); \
__result; \
})
#else
#define mad_f_scale64(hi, lo) \
({ \
mad_fixed_t __result; \
asm("rotrwi %0,%1,%2" \
: "=r"(__result) \
: "r"(lo), "i"(MAD_F_SCALEBITS)); \
asm("insrwi %0,%1,%2,0" \
: "+r"(__result) \
: "r"(hi), "i"(MAD_F_SCALEBITS)); \
__result; \
})
#endif
#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.
*/
#if defined(OPT_SPEED)
#define mad_f_mul(x, y) (((x) >> 12) * ((y) >> 16))
#else
#define mad_f_mul(x, y) ((((x) + (1L << 11)) >> 12) * \
(((y) + (1L << 15)) >> 16))
#endif
/* ------------------------------------------------------------------------- */
#else
#error "no FPM selected"
#endif
/* default implementations */
#if !defined(mad_f_mul)
#define mad_f_mul(x, y) \
({ \
register mad_fixed64hi_t __hi; \
register mad_fixed64lo_t __lo; \
MAD_F_MLX(__hi, __lo, (x), (y)); \
mad_f_scale64(__hi, __lo); \
})
#endif
#if !defined(MAD_F_MLA)
#define MAD_F_ML0(hi, lo, x, y) ((lo) = mad_f_mul((x), (y)))
#define MAD_F_MLA(hi, lo, x, y) ((lo) += mad_f_mul((x), (y)))
#define MAD_F_MLN(hi, lo) ((lo) = -(lo))
#define MAD_F_MLZ(hi, lo) ((void)(hi), (mad_fixed_t)(lo))
#endif
#if !defined(MAD_F_ML0)
#define MAD_F_ML0(hi, lo, x, y) MAD_F_MLX((hi), (lo), (x), (y))
#endif
#if !defined(MAD_F_MLN)
#define MAD_F_MLN(hi, lo) ((hi) = ((lo) = -(lo)) ? ~(hi) : -(hi))
#endif
#if !defined(MAD_F_MLZ)
#define MAD_F_MLZ(hi, lo) mad_f_scale64((hi), (lo))
#endif
#if !defined(mad_f_scale64)
#if defined(OPT_ACCURACY)
#define mad_f_scale64(hi, lo) \
((((mad_fixed_t)(((hi) << (32 - (MAD_F_SCALEBITS - 1))) | \
((lo) >> (MAD_F_SCALEBITS - 1)))) + \
1) >> \
1)
#else
#define mad_f_scale64(hi, lo) \
((mad_fixed_t)(((hi) << (32 - MAD_F_SCALEBITS)) | \
((lo) >> MAD_F_SCALEBITS)))
#endif
#define MAD_F_SCALEBITS MAD_F_FRACBITS
#endif
/* C routines */
mad_fixed_t mad_f_abs(mad_fixed_t);
mad_fixed_t mad_f_div(mad_fixed_t, mad_fixed_t);
#endif