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gcc/libgcc/fixed-bit.c
Richard Sandiford 5d5bf77569 Update copyright in libgcc. 
From-SVN: r195731
2013-02-04 19:06:20 +00:00

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/* This is a software fixed-point library.
Copyright (C) 2007-2013 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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 3, or (at your option) any later
version.
GCC 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* This implements fixed-point arithmetic.
Contributed by Chao-ying Fu <fu@mips.com>. */
/* To use this file, we need to define one of the following:
QQ_MODE, UQQ_MODE, HQ_MODE, UHQ_MODE, SQ_MODE, USQ_MODE, DQ_MODE, UDQ_MODE,
TQ_MODE, UTQ_MODE, HA_MODE, UHA_MODE, SA_MODE, USA_MODE, DA_MODE, UDA_MODE,
TA_MODE, UTA_MODE.
Then, all operators for this machine mode will be created.
Or, we need to define FROM_* TO_* for conversions from one mode to another
mode. The mode could be one of the following:
Fract: QQ, UQQ, HQ, UHQ, SQ, USQ, DQ, UDQ, TQ, UTQ
Accum: HA, UHA, SA, USA, DA, UDA, TA, UTA
Signed integer: QI, HI, SI, DI, TI
Unsigned integer: UQI, UHI, USI, UDI, UTI
Floating-point: SF, DF
Ex: If we define FROM_QQ and TO_SI, the conversion from QQ to SI is
generated. */
#include "tconfig.h"
#include "tsystem.h"
#include "coretypes.h"
#include "tm.h"
#include "libgcc_tm.h"
#ifndef MIN_UNITS_PER_WORD
#define MIN_UNITS_PER_WORD UNITS_PER_WORD
#endif
#include "fixed-bit.h"
#if defined(FIXED_ADD) && defined(L_add)
FIXED_C_TYPE
FIXED_ADD (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y, z;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
z = x + y;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_ADD */
#if defined(FIXED_SSADD) && defined(L_ssadd)
FIXED_C_TYPE
FIXED_SSADD (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y, z;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
z = x + (UINT_C_TYPE) y;
if ((((x ^ y) >> I_F_BITS) & 1) == 0)
{
if (((z ^ x) >> I_F_BITS) & 1)
{
z = ((UINT_C_TYPE) 1) << I_F_BITS;
if (x >= 0)
z -= (UINT_C_TYPE) 1;
}
}
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_SSADD */
#if defined(FIXED_USADD) && defined(L_usadd)
FIXED_C_TYPE
FIXED_USADD (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y, z;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
z = x + y;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
if (z < x || z < y) /* max */
{
z = -1;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
}
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_USADD */
#if defined(FIXED_SUB) && defined(L_sub)
FIXED_C_TYPE
FIXED_SUB (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y, z;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
z = x - y;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_SUB */
#if defined(FIXED_SSSUB) && defined(L_sssub)
FIXED_C_TYPE
FIXED_SSSUB (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y, z;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
z = x - (UINT_C_TYPE) y;
if (((x ^ y) >> I_F_BITS) & 1)
{
if (((z ^ x) >> I_F_BITS) & 1)
{
z = ((UINT_C_TYPE) 1) << I_F_BITS;
if (x >= 0)
z -= (UINT_C_TYPE) 1;
}
}
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_SSSUB */
#if defined(FIXED_USSUB) && defined(L_ussub)
FIXED_C_TYPE
FIXED_USSUB (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y, z;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
z = x - y;
if (x < y)
z = 0;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_USSUB */
#if defined(FIXED_SATURATE1) && defined(L_saturate1)
void
FIXED_SATURATE1 (DINT_C_TYPE *a)
{
DINT_C_TYPE max, min;
max = (DINT_C_TYPE)1 << I_F_BITS;
max = max - 1;
#if MODE_UNSIGNED == 0
min = (DINT_C_TYPE)1 << (2 * FIXED_WIDTH - 1);
min = min >> (2 * FIXED_WIDTH - 1 - I_F_BITS);
#else
min = 0;
#endif
if (*a > max)
*a = max;
else if (*a < min)
*a = min;
}
#endif /* FIXED_SATURATE1 */
#if defined(FIXED_SATURATE2) && defined(L_saturate2)
void
FIXED_SATURATE2 (INT_C_TYPE *high, INT_C_TYPE *low)
{
INT_C_TYPE r_max, s_max, r_min, s_min;
r_max = 0;
#if (MODE_UNSIGNED == 0) || HAVE_PADDING_BITS
s_max = (INT_C_TYPE)1 << I_F_BITS;
s_max = s_max - 1;
#else
s_max = -1;
#endif
#if MODE_UNSIGNED == 0
r_min = -1;
s_min = (INT_C_TYPE)1 << (FIXED_WIDTH - 1);
s_min = s_min >> (FIXED_WIDTH - 1 - I_F_BITS);
#else
r_min = 0;
s_min = 0;
#endif
if (*high > r_max
|| (*high == r_max && (UINT_C_TYPE)(*low) > (UINT_C_TYPE)s_max))
{
*high = r_max;
*low = s_max;
}
else if (*high < r_min ||
(*high == r_min && (UINT_C_TYPE)(*low) < (UINT_C_TYPE)s_min))
{
*high = r_min;
*low = s_min;
}
}
#endif /* FIXED_SATURATE2 */
#if defined(FIXED_MULHELPER) && defined(L_mulhelper)
FIXED_C_TYPE
FIXED_MULHELPER (FIXED_C_TYPE a, FIXED_C_TYPE b, word_type satp)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y;
#if defined (DINT_C_TYPE)
INT_C_TYPE z;
DINT_C_TYPE dx, dy, dz;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
dx = (DINT_C_TYPE) x;
dy = (DINT_C_TYPE) y;
dz = dx * dy;
/* Round the result by adding (1 << (FBITS -1)). */
dz += ((DINT_C_TYPE) 1 << (FBITS - 1));
dz = dz >> FBITS;
if (satp)
FIXED_SATURATE1 (&dz);
z = (INT_C_TYPE) dz;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
#else /* No DINT_C_TYPE */
/* The result of multiplication expands to two INT_C_TYPE. */
INTunion aa, bb;
INTunion a_high, a_low, b_high, b_low;
INTunion high_high, high_low, low_high, low_low;
INTunion r, s, temp1, temp2;
INT_C_TYPE carry = 0;
INT_C_TYPE z;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
/* Decompose a and b. */
aa.ll = x;
bb.ll = y;
a_high.s.low = aa.s.high;
a_high.s.high = 0;
a_low.s.low = aa.s.low;
a_low.s.high = 0;
b_high.s.low = bb.s.high;
b_high.s.high = 0;
b_low.s.low = bb.s.low;
b_low.s.high = 0;
/* Perform four multiplications. */
low_low.ll = a_low.ll * b_low.ll;
low_high.ll = a_low.ll * b_high.ll;
high_low.ll = a_high.ll * b_low.ll;
high_high.ll = a_high.ll * b_high.ll;
/* Accumulate four results to {r, s}. */
temp1.s.high = high_low.s.low;
temp1.s.low = 0;
s.ll = low_low.ll + temp1.ll;
if ((UINT_C_TYPE) s.ll < (UINT_C_TYPE) low_low.ll
|| (UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp1.ll)
carry ++; /* Carry. */
temp1.ll = s.ll;
temp2.s.high = low_high.s.low;
temp2.s.low = 0;
s.ll = temp1.ll + temp2.ll;
if ((UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp1.ll
|| (UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp2.ll)
carry ++; /* Carry. */
temp1.s.low = high_low.s.high;
temp1.s.high = 0;
r.ll = high_high.ll + temp1.ll;
temp1.s.low = low_high.s.high;
temp1.s.high = 0;
r.ll = r.ll + temp1.ll + carry;
#if MODE_UNSIGNED == 0
/* For signed types, we need to add neg(y) to r, if x < 0. */
if (x < 0)
r.ll = r.ll - y;
/* We need to add neg(x) to r, if y < 0. */
if (y < 0)
r.ll = r.ll - x;
#endif
/* Round the result by adding (1 << (FBITS -1)). */
temp1.ll = s.ll;
s.ll += ((INT_C_TYPE) 1 << (FBITS -1));
if ((UINT_C_TYPE) s.ll < (UINT_C_TYPE) temp1.ll
|| (UINT_C_TYPE) s.ll < (UINT_C_TYPE) ((INT_C_TYPE) 1 << (FBITS -1)))
r.ll += 1;
/* Shift right the result by FBITS. */
#if FBITS == FIXED_WIDTH
/* This happens only for unsigned types without any padding bits.
So, it is safe to set r.ll to 0 as it is logically shifted right. */
s.ll = r.ll;
r.ll = 0;
#else
s.ll = ((UINT_C_TYPE)s.ll) >> FBITS;
temp1.ll = r.ll << (FIXED_WIDTH - FBITS);
s.ll = s.ll | temp1.ll;
r.ll = r.ll >> FBITS;
#endif
if (satp)
FIXED_SATURATE2 (&r.ll, &s.ll);
z = (INT_C_TYPE) s.ll;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
#endif
}
#endif /* FIXED_MULHELPER */
#if defined(FIXED_MUL) && defined(L_mul)
FIXED_C_TYPE
FIXED_MUL (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
return FIXED_MULHELPER (a, b, 0);
}
#endif /* FIXED_MUL */
#if defined(FIXED_SSMUL) && defined(L_ssmul)
FIXED_C_TYPE
FIXED_SSMUL (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
return FIXED_MULHELPER (a, b, 1);
}
#endif /* FIXED_SSMUL */
#if defined(FIXED_USMUL) && defined(L_usmul)
FIXED_C_TYPE
FIXED_USMUL (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
return FIXED_MULHELPER (a, b, 1);
}
#endif /* FIXED_USMUL */
#if defined(FIXED_DIVHELPER) && defined(L_divhelper)
FIXED_C_TYPE
FIXED_DIVHELPER (FIXED_C_TYPE a, FIXED_C_TYPE b, word_type satp)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y;
INT_C_TYPE z;
#if defined (DINT_C_TYPE)
DINT_C_TYPE dx, dy, dz;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
dx = (DINT_C_TYPE) x;
dy = (DINT_C_TYPE) y;
dx = dx << FBITS;
dz = dx / dy;
if (satp)
FIXED_SATURATE1 (&dz);
z = (INT_C_TYPE) dz;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
#else /* No DINT_C_TYPE */
INT_C_TYPE pos_a, pos_b, r, s;
INT_C_TYPE quo_r, quo_s, mod, temp;
word_type i;
#if MODE_UNSIGNED == 0
word_type num_of_neg = 0;
#endif
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
pos_a = x;
pos_b = y;
#if MODE_UNSIGNED == 0
/* If a < 0, negate a. */
if (pos_a < 0)
{
pos_a = -pos_a;
num_of_neg ++;
}
/* If b < 0, negate b. */
if (pos_b < 0)
{
pos_b = -pos_b;
num_of_neg ++;
}
#endif
/* Left shift pos_a to {r, s} by FBITS. */
#if FBITS == FIXED_WIDTH
/* This happens only for unsigned types without any padding bits. */
r = pos_a;
s = 0;
#else
s = pos_a << FBITS;
r = pos_a >> (FIXED_WIDTH - FBITS);
#endif
/* Unsigned divide r by pos_b to quo_r. The remainder is in mod. */
quo_r = (UINT_C_TYPE)r / (UINT_C_TYPE)pos_b;
mod = (UINT_C_TYPE)r % (UINT_C_TYPE)pos_b;
quo_s = 0;
for (i = 0; i < FIXED_WIDTH; i++)
{
/* Record the leftmost bit of mod. */
word_type leftmost_mode = (mod >> (FIXED_WIDTH - 1)) & 1;
/* Shift left mod by 1 bit. */
mod = mod << 1;
/* Test the leftmost bit of s to add to mod. */
if ((s >> (FIXED_WIDTH - 1)) & 1)
mod ++;
/* Shift left quo_s by 1 bit. */
quo_s = quo_s << 1;
/* Try to calculate (mod - pos_b). */
temp = mod - pos_b;
if (leftmost_mode || (UINT_C_TYPE)mod >= (UINT_C_TYPE)pos_b)
{
quo_s ++;
mod = temp;
}
/* Shift left s by 1 bit. */
s = s << 1;
}
#if MODE_UNSIGNED == 0
if (num_of_neg == 1)
{
quo_s = -quo_s;
if (quo_s == 0)
quo_r = -quo_r;
else
quo_r = ~quo_r;
}
#endif
if (satp)
FIXED_SATURATE2 (&quo_r, &quo_s);
z = quo_s;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
#endif
}
#endif /* FIXED_DIVHELPER */
#if defined(FIXED_DIV) && defined(L_div)
FIXED_C_TYPE
FIXED_DIV (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
return FIXED_DIVHELPER (a, b, 0);
}
#endif /* FIXED_DIV */
#if defined(FIXED_UDIV) && defined(L_udiv)
FIXED_C_TYPE
FIXED_UDIV (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
return FIXED_DIVHELPER (a, b, 0);
}
#endif /* FIXED_UDIV */
#if defined(FIXED_SSDIV) && defined(L_ssdiv)
FIXED_C_TYPE
FIXED_SSDIV (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
return FIXED_DIVHELPER (a, b, 1);
}
#endif /* FIXED_SSDIV */
#if defined(FIXED_USDIV) && defined(L_usdiv)
FIXED_C_TYPE
FIXED_USDIV (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
return FIXED_DIVHELPER (a, b, 1);
}
#endif /* FIXED_USDIV */
#if defined(FIXED_NEG) && defined(L_neg)
FIXED_C_TYPE
FIXED_NEG (FIXED_C_TYPE a)
{
FIXED_C_TYPE c;
INT_C_TYPE x, z;
memcpy (&x, &a, FIXED_SIZE);
z = -x;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_NEG */
#if defined(FIXED_SSNEG) && defined(L_ssneg)
FIXED_C_TYPE
FIXED_SSNEG (FIXED_C_TYPE a)
{
FIXED_C_TYPE c;
INT_C_TYPE x, y, z;
memcpy (&y, &a, FIXED_SIZE);
x = 0;
z = x - (UINT_C_TYPE) y;
if (((x ^ y) >> I_F_BITS) & 1)
{
if (((z ^ x) >> I_F_BITS) & 1)
z = (((UINT_C_TYPE) 1) << I_F_BITS) - 1;
}
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_SSNEG */
#if defined(FIXED_USNEG) && defined(L_usneg)
FIXED_C_TYPE
FIXED_USNEG (FIXED_C_TYPE a __attribute__ ((__unused__)))
{
FIXED_C_TYPE c;
INT_C_TYPE z;
z = 0;
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_USNEG */
#if defined(FIXED_ASHLHELPER) && defined(L_ashlhelper)
FIXED_C_TYPE
FIXED_ASHLHELPER (FIXED_C_TYPE a, word_type b, word_type satp)
{
FIXED_C_TYPE c;
INT_C_TYPE x, z;
#if defined (DINT_C_TYPE)
DINT_C_TYPE dx, dz;
memcpy (&x, &a, FIXED_SIZE);
dx = (DINT_C_TYPE) x;
if (b >= FIXED_WIDTH)
dz = dx << FIXED_WIDTH;
else
dz = dx << b;
if (satp)
FIXED_SATURATE1 (&dz);
z = (INT_C_TYPE) dz;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
#else /* No DINT_C_TYPE */
INT_C_TYPE r, s;
memcpy (&x, &a, FIXED_SIZE);
/* We need to shift left x by b bits to {r, s}. */
if (b >= FIXED_WIDTH)
{
r = b;
s = 0;
}
else
{
s = x << b;
r = x >> (FIXED_WIDTH - b);
}
if (satp)
FIXED_SATURATE2 (&r, &s);
z = s;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
#endif
}
#endif /* FIXED_ASHLHELPER */
#if defined(FIXED_ASHL) && defined(L_ashl)
FIXED_C_TYPE
FIXED_ASHL (FIXED_C_TYPE a, word_type b)
{
return FIXED_ASHLHELPER (a, b, 0);
}
#endif /* FIXED_ASHL */
#if defined(FIXED_ASHR) && defined(L_ashr)
FIXED_C_TYPE
FIXED_ASHR (FIXED_C_TYPE a, word_type b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, z;
memcpy (&x, &a, FIXED_SIZE);
z = x >> b;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_ASHR */
#if defined(FIXED_LSHR) && defined(L_lshr)
FIXED_C_TYPE
FIXED_LSHR (FIXED_C_TYPE a, word_type b)
{
FIXED_C_TYPE c;
INT_C_TYPE x, z;
memcpy (&x, &a, FIXED_SIZE);
z = x >> b;
#if HAVE_PADDING_BITS
z = z << PADDING_BITS;
z = z >> PADDING_BITS;
#endif
memcpy (&c, &z, FIXED_SIZE);
return c;
}
#endif /* FIXED_LSHR */
#if defined(FIXED_SSASHL) && defined(L_ssashl)
FIXED_C_TYPE
FIXED_SSASHL (FIXED_C_TYPE a, word_type b)
{
return FIXED_ASHLHELPER (a, b, 1);
}
#endif /* FIXED_SSASHL */
#if defined(FIXED_USASHL) && defined(L_usashl)
FIXED_C_TYPE
FIXED_USASHL (FIXED_C_TYPE a, word_type b)
{
return FIXED_ASHLHELPER (a, b, 1);
}
#endif /* FIXED_USASHL */
#if defined(FIXED_CMP) && defined(L_cmp)
word_type
FIXED_CMP (FIXED_C_TYPE a, FIXED_C_TYPE b)
{
INT_C_TYPE x, y;
memcpy (&x, &a, FIXED_SIZE);
memcpy (&y, &b, FIXED_SIZE);
if (x < y)
return 0;
else if (x > y)
return 2;
return 1;
}
#endif /* FIXED_CMP */
/* Fixed -> Fixed. */
#if defined(FRACT) && defined(L_fract) && FROM_TYPE == 4 && TO_TYPE == 4
TO_FIXED_C_TYPE
FRACT (FROM_FIXED_C_TYPE a)
{
TO_FIXED_C_TYPE c;
FROM_INT_C_TYPE x;
TO_INT_C_TYPE z;
int shift_amount;
memcpy (&x, &a, FROM_FIXED_SIZE);
#if TO_FBITS > FROM_FBITS /* Need left shift. */
shift_amount = TO_FBITS - FROM_FBITS;
z = (TO_INT_C_TYPE) x;
z = z << shift_amount;
#else /* TO_FBITS <= FROM_FBITS. Need right Shift. */
shift_amount = FROM_FBITS - TO_FBITS;
x = x >> shift_amount;
z = (TO_INT_C_TYPE) x;
#endif /* TO_FBITS > FROM_FBITS */
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* FRACT && FROM_TYPE == 4 && TO_TYPE == 4 */
/* Fixed -> Fixed with saturation. */
#if defined(SATFRACT) && defined(L_satfract) && FROM_TYPE == 4 && TO_TYPE == 4
TO_FIXED_C_TYPE
SATFRACT (FROM_FIXED_C_TYPE a)
{
TO_FIXED_C_TYPE c;
TO_INT_C_TYPE z;
FROM_INT_C_TYPE x;
#if FROM_MODE_UNSIGNED == 0
BIG_SINT_C_TYPE high, low;
BIG_SINT_C_TYPE max_high, max_low;
#if TO_MODE_UNSIGNED == 0
BIG_SINT_C_TYPE min_high, min_low;
#endif
#else
BIG_UINT_C_TYPE high, low;
BIG_UINT_C_TYPE max_high, max_low;
#endif
#if TO_FBITS > FROM_FBITS
BIG_UINT_C_TYPE utemp;
#endif
#if TO_MODE_UNSIGNED == 0
BIG_SINT_C_TYPE stemp;
#endif
#if TO_FBITS != FROM_FBITS
int shift_amount;
#endif
memcpy (&x, &a, FROM_FIXED_SIZE);
/* Step 1. We need to store x to {high, low}. */
#if FROM_MODE_UNSIGNED == 0
low = (BIG_SINT_C_TYPE) x;
if (x < 0)
high = -1;
else
high = 0;
#else
low = (BIG_UINT_C_TYPE) x;
high = 0;
#endif
/* Step 2. We need to shift {high, low}. */
#if TO_FBITS > FROM_FBITS /* Left shift. */
shift_amount = TO_FBITS - FROM_FBITS;
utemp = (BIG_UINT_C_TYPE) low;
utemp = utemp >> (BIG_WIDTH - shift_amount);
high = ((BIG_UINT_C_TYPE)(high << shift_amount)) | utemp;
low = low << shift_amount;
#elif TO_FBITS < FROM_FBITS /* Right shift. */
shift_amount = FROM_FBITS - TO_FBITS;
low = low >> shift_amount;
#endif
/* Step 3. Compare {high, low} with max and min of TO_FIXED_C_TYPE. */
max_high = 0;
#if BIG_WIDTH > TO_FIXED_WIDTH || TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS
max_low = (BIG_UINT_C_TYPE)1 << TO_I_F_BITS;
max_low = max_low - 1;
#else
max_low = -1;
#endif
#if TO_MODE_UNSIGNED == 0
stemp = (BIG_SINT_C_TYPE)1 << (BIG_WIDTH - 1);
stemp = stemp >> (BIG_WIDTH - 1 - TO_I_F_BITS);
#if FROM_MODE_UNSIGNED == 0
min_high = -1;
min_low = stemp;
#endif
#endif
#if FROM_MODE_UNSIGNED == 0 && TO_MODE_UNSIGNED == 0
/* Signed -> Signed. */
if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high
|| ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
else if ((BIG_SINT_C_TYPE) high < (BIG_SINT_C_TYPE) min_high
|| ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) min_high
&& (BIG_UINT_C_TYPE) low < (BIG_UINT_C_TYPE) min_low))
low = min_low; /* Minimum. */
#elif FROM_MODE_UNSIGNED == 1 && TO_MODE_UNSIGNED == 1
/* Unigned -> Unsigned. */
if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high
|| ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
#elif FROM_MODE_UNSIGNED == 0 && TO_MODE_UNSIGNED == 1
/* Signed -> Unsigned. */
if (x < 0)
low = 0; /* Minimum. */
else if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high
|| ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
#elif FROM_MODE_UNSIGNED == 1 && TO_MODE_UNSIGNED == 0
/* Unsigned -> Signed. */
if ((BIG_SINT_C_TYPE) high < 0)
low = max_low; /* Maximum. */
else if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high
|| ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
#endif
/* Step 4. Store the result. */
z = (TO_INT_C_TYPE) low;
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* defined(SATFRACT) && FROM_TYPE == 4 && TO_TYPE == 4 */
/* Fixed -> Int. */
#if defined(FRACT) && defined(L_fract) && FROM_TYPE == 4 && TO_TYPE == 1
TO_INT_C_TYPE
FRACT (FROM_FIXED_C_TYPE a)
{
FROM_INT_C_TYPE x;
TO_INT_C_TYPE z;
FROM_INT_C_TYPE i = 0;
memcpy (&x, &a, FROM_FIXED_SIZE);
#if FROM_MODE_UNSIGNED == 0
if (x < 0)
{
#if FROM_FIXED_WIDTH == FROM_FBITS
if (x != 0)
i = 1;
#else
if (((FROM_INT_C_TYPE)(x << (FROM_FIXED_WIDTH - FROM_FBITS))) != 0)
i = 1;
#endif
}
#endif
#if FROM_FIXED_WIDTH == FROM_FBITS
x = 0;
#else
x = x >> FROM_FBITS;
#endif
x = x + i;
z = (TO_INT_C_TYPE) x;
return z;
}
#endif /* defined(FRACT) && FROM_TYPE == 4 && TO_TYPE == 1 */
/* Fixed -> Unsigned int. */
#if defined(FRACTUNS) && defined(L_fractuns) && FROM_TYPE == 4 && TO_TYPE == 2
TO_INT_C_TYPE
FRACTUNS (FROM_FIXED_C_TYPE a)
{
FROM_INT_C_TYPE x;
TO_INT_C_TYPE z;
FROM_INT_C_TYPE i = 0;
memcpy (&x, &a, FROM_FIXED_SIZE);
#if FROM_MODE_UNSIGNED == 0
if (x < 0)
{
#if FROM_FIXED_WIDTH == FROM_FBITS
if (x != 0)
i = 1;
#else
if (((FROM_INT_C_TYPE)(x << (FROM_FIXED_WIDTH - FROM_FBITS))) != 0)
i = 1;
#endif
}
#endif
#if FROM_FIXED_WIDTH == FROM_FBITS
x = 0;
#else
x = x >> FROM_FBITS;
#endif
x = x + i;
z = (TO_INT_C_TYPE) x;
return z;
}
#endif /* defined(FRACTUNS) && FROM_TYPE == 4 && TO_TYPE == 2 */
/* Int -> Fixed. */
#if defined(FRACT) && defined(L_fract) && FROM_TYPE == 1 && TO_TYPE == 4
TO_FIXED_C_TYPE
FRACT (FROM_INT_C_TYPE a)
{
TO_FIXED_C_TYPE c;
TO_INT_C_TYPE z;
z = (TO_INT_C_TYPE) a;
#if TO_FIXED_WIDTH == TO_FBITS
z = 0;
#else
z = z << TO_FBITS;
#endif
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* defined(FRACT) && FROM_TYPE == 1 && TO_TYPE == 4 */
/* Signed int -> Fixed with saturation. */
#if defined(SATFRACT) && defined(L_satfract) && FROM_TYPE == 1 && TO_TYPE == 4
TO_FIXED_C_TYPE
SATFRACT (FROM_INT_C_TYPE a)
{
TO_FIXED_C_TYPE c;
TO_INT_C_TYPE z;
FROM_INT_C_TYPE x = a;
BIG_SINT_C_TYPE high, low;
BIG_SINT_C_TYPE max_high, max_low;
#if TO_MODE_UNSIGNED == 0
BIG_SINT_C_TYPE min_high, min_low;
BIG_SINT_C_TYPE stemp;
#endif
#if BIG_WIDTH != TO_FBITS
BIG_UINT_C_TYPE utemp;
int shift_amount;
#endif
/* Step 1. We need to store x to {high, low}. */
low = (BIG_SINT_C_TYPE) x;
if (x < 0)
high = -1;
else
high = 0;
/* Step 2. We need to left shift {high, low}. */
#if BIG_WIDTH == TO_FBITS
high = low;
low = 0;
#else
shift_amount = TO_FBITS;
utemp = (BIG_UINT_C_TYPE) low;
utemp = utemp >> (BIG_WIDTH - shift_amount);
high = ((BIG_UINT_C_TYPE)(high << shift_amount)) | utemp;
low = low << shift_amount;
#endif
/* Step 3. Compare {high, low} with max and min of TO_FIXED_C_TYPE. */
max_high = 0;
#if BIG_WIDTH > TO_FIXED_WIDTH || TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS
max_low = (BIG_UINT_C_TYPE)1 << TO_I_F_BITS;
max_low = max_low - 1;
#else
max_low = -1;
#endif
#if TO_MODE_UNSIGNED == 0
min_high = -1;
stemp = (BIG_SINT_C_TYPE)1 << (BIG_WIDTH - 1);
stemp = stemp >> (BIG_WIDTH - 1 - TO_I_F_BITS);
min_low = stemp;
/* Signed -> Signed. */
if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high
|| ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
else if ((BIG_SINT_C_TYPE) high < (BIG_SINT_C_TYPE) min_high
|| ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) min_high
&& (BIG_UINT_C_TYPE) low < (BIG_UINT_C_TYPE) min_low))
low = min_low; /* Minimum. */
#else
/* Signed -> Unsigned. */
if (x < 0)
low = 0; /* Minimum. */
else if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high
|| ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
#endif
/* Step 4. Store the result. */
z = (TO_INT_C_TYPE) low;
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* defined(SATFRACT) && FROM_TYPE == 1 && TO_TYPE == 4 */
/* Unsigned int -> Fixed. */
#if defined(FRACTUNS) && defined(L_fractuns) &&FROM_TYPE == 2 && TO_TYPE == 4
TO_FIXED_C_TYPE
FRACTUNS (FROM_INT_C_TYPE a)
{
TO_FIXED_C_TYPE c;
TO_INT_C_TYPE z;
z = (TO_INT_C_TYPE) a;
#if TO_FIXED_WIDTH == TO_FBITS
z = 0;
#else
z = z << TO_FBITS;
#endif
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* defined(FRACTUNS) && FROM_TYPE == 2 && TO_TYPE == 4 */
/* Unsigned int -> Fixed with saturation. */
#if defined(SATFRACTUNS) && defined(L_satfractuns) && FROM_TYPE == 2 && TO_TYPE == 4
TO_FIXED_C_TYPE
SATFRACTUNS (FROM_INT_C_TYPE a)
{
TO_FIXED_C_TYPE c;
TO_INT_C_TYPE z;
FROM_INT_C_TYPE x = a;
BIG_UINT_C_TYPE high, low;
BIG_UINT_C_TYPE max_high, max_low;
#if BIG_WIDTH != TO_FBITS
BIG_UINT_C_TYPE utemp;
int shift_amount;
#endif
/* Step 1. We need to store x to {high, low}. */
low = (BIG_UINT_C_TYPE) x;
high = 0;
/* Step 2. We need to left shift {high, low}. */
#if BIG_WIDTH == TO_FBITS
high = low;
low = 0;
#else
shift_amount = TO_FBITS;
utemp = (BIG_UINT_C_TYPE) low;
utemp = utemp >> (BIG_WIDTH - shift_amount);
high = ((BIG_UINT_C_TYPE)(high << shift_amount)) | utemp;
low = low << shift_amount;
#endif
/* Step 3. Compare {high, low} with max and min of TO_FIXED_C_TYPE. */
max_high = 0;
#if BIG_WIDTH > TO_FIXED_WIDTH || TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS
max_low = (BIG_UINT_C_TYPE)1 << TO_I_F_BITS;
max_low = max_low - 1;
#else
max_low = -1;
#endif
#if TO_MODE_UNSIGNED == 1
/* Unigned -> Unsigned. */
if ((BIG_UINT_C_TYPE) high > (BIG_UINT_C_TYPE) max_high
|| ((BIG_UINT_C_TYPE) high == (BIG_UINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
#else
/* Unsigned -> Signed. */
if ((BIG_SINT_C_TYPE) high < 0)
low = max_low; /* Maximum. */
else if ((BIG_SINT_C_TYPE) high > (BIG_SINT_C_TYPE) max_high
|| ((BIG_SINT_C_TYPE) high == (BIG_SINT_C_TYPE) max_high
&& (BIG_UINT_C_TYPE) low > (BIG_UINT_C_TYPE) max_low))
low = max_low; /* Maximum. */
#endif
/* Step 4. Store the result. */
z = (TO_INT_C_TYPE) low;
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* defined(SATFRACTUNS) && FROM_TYPE == 2 && TO_TYPE == 4 */
/* Fixed -> Float. */
#if defined(FRACT) && defined(L_fract) && FROM_TYPE == 4 && TO_TYPE == 3
TO_FLOAT_C_TYPE
FRACT (FROM_FIXED_C_TYPE a)
{
FROM_INT_C_TYPE x;
TO_FLOAT_C_TYPE z;
memcpy (&x, &a, FROM_FIXED_SIZE);
z = (TO_FLOAT_C_TYPE) x;
z = z / BASE;
return z;
}
#endif /* defined(FRACT) && FROM_TYPE == 4 && TO_TYPE == 3 */
/* Float -> Fixed. */
#if defined(FRACT) && defined(L_fract) && FROM_TYPE == 3 && TO_TYPE == 4
TO_FIXED_C_TYPE
FRACT (FROM_FLOAT_C_TYPE a)
{
FROM_FLOAT_C_TYPE temp;
TO_INT_C_TYPE z;
TO_FIXED_C_TYPE c;
temp = a * BASE;
z = (TO_INT_C_TYPE) temp;
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* defined(FRACT) && FROM_TYPE == 3 && TO_TYPE == 4 */
/* Float -> Fixed with saturation. */
#if defined(SATFRACT) && defined(L_satfract) && FROM_TYPE == 3 && TO_TYPE == 4
TO_FIXED_C_TYPE
SATFRACT (FROM_FLOAT_C_TYPE a)
{
FROM_FLOAT_C_TYPE temp;
TO_INT_C_TYPE z;
TO_FIXED_C_TYPE c;
if (a >= FIXED_MAX)
{
#if TO_MODE_UNSIGNED == 0 || TO_HAVE_PADDING_BITS
z = (TO_INT_C_TYPE)1 << TO_I_F_BITS;
z = z - 1;
#else
z = -1;
#endif
}
else if (a <= FIXED_MIN)
{
#if TO_MODE_UNSIGNED == 0
z = (TO_INT_C_TYPE)1 << TO_I_F_BITS;
#else
z = 0;
#endif
}
else
{
temp = a * BASE;
z = (TO_INT_C_TYPE) temp;
}
#if TO_HAVE_PADDING_BITS
z = z << TO_PADDING_BITS;
z = z >> TO_PADDING_BITS;
#endif
memcpy (&c, &z, TO_FIXED_SIZE);
return c;
}
#endif /* defined(SATFRACT) && FROM_TYPE == 3 && TO_TYPE == 4 */
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