aboutsummaryrefslogtreecommitdiffstats
path: root/src/libmad/fixed.h
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/libmad/fixed.h484
1 files changed, 484 insertions, 0 deletions
diff --git a/src/libmad/fixed.h b/src/libmad/fixed.h
new file mode 100644
index 000000000..241e7f95e
--- /dev/null
+++ b/src/libmad/fixed.h
@@ -0,0 +1,484 @@
+/*
+ * libmad - MPEG audio decoder library
+ * Copyright (C) 2000-2003 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 1.1 2003/08/14 03:57:13 shank Exp $
+ */
+
+# ifndef LIBMAD_FIXED_H
+# define LIBMAD_FIXED_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; \
+ })
+# 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
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-17 00:54:44 +0000