u-boot/arch/nios2/lib/longlong.h
Thomas Chou 1a05b5f91e nios2: fix missing comment terminator from SPDX License commit
The commit 1a4596601f
  Add GPL-2.0+ SPDX-License-Identifier to source files

generated a warning due to a missing comment terminator.
  longlong.h:7:1: warning: "/*" within comment

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
2013-09-06 11:03:42 +08:00

252 lines
8.4 KiB
C

/* longlong.h -- definitions for mixed size 32/64 bit arithmetic.
Copyright (C) 1991, 1992, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2004,
2005 Free Software Foundation, Inc.
* SPDX-License-Identifier: GPL-2.0+
*/
/* You have to define the following before including this file:
UWtype -- An unsigned type, default type for operations (typically a "word")
UHWtype -- An unsigned type, at least half the size of UWtype.
UDWtype -- An unsigned type, at least twice as large a UWtype
W_TYPE_SIZE -- size in bits of UWtype
UQItype -- Unsigned 8 bit type.
SItype, USItype -- Signed and unsigned 32 bit types.
DItype, UDItype -- Signed and unsigned 64 bit types.
On a 32 bit machine UWtype should typically be USItype;
on a 64 bit machine, UWtype should typically be UDItype. */
#define __BITS4 (W_TYPE_SIZE / 4)
#define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
#define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
#define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
#ifndef W_TYPE_SIZE
#define W_TYPE_SIZE 32
#define UWtype USItype
#define UHWtype USItype
#define UDWtype UDItype
#endif
extern const UQItype __clz_tab[256];
/* Define auxiliary asm macros.
1) umul_ppmm(high_prod, low_prod, multiplier, multiplicand) multiplies two
UWtype integers MULTIPLIER and MULTIPLICAND, and generates a two UWtype
word product in HIGH_PROD and LOW_PROD.
2) __umulsidi3(a,b) multiplies two UWtype integers A and B, and returns a
UDWtype product. This is just a variant of umul_ppmm.
3) udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
denominator) divides a UDWtype, composed by the UWtype integers
HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and places the quotient
in QUOTIENT and the remainder in REMAINDER. HIGH_NUMERATOR must be less
than DENOMINATOR for correct operation. If, in addition, the most
significant bit of DENOMINATOR must be 1, then the pre-processor symbol
UDIV_NEEDS_NORMALIZATION is defined to 1.
4) sdiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
denominator). Like udiv_qrnnd but the numbers are signed. The quotient
is rounded towards 0.
5) count_leading_zeros(count, x) counts the number of zero-bits from the
msb to the first nonzero bit in the UWtype X. This is the number of
steps X needs to be shifted left to set the msb. Undefined for X == 0,
unless the symbol COUNT_LEADING_ZEROS_0 is defined to some value.
6) count_trailing_zeros(count, x) like count_leading_zeros, but counts
from the least significant end.
7) add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,
high_addend_2, low_addend_2) adds two UWtype integers, composed by
HIGH_ADDEND_1 and LOW_ADDEND_1, and HIGH_ADDEND_2 and LOW_ADDEND_2
respectively. The result is placed in HIGH_SUM and LOW_SUM. Overflow
(i.e. carry out) is not stored anywhere, and is lost.
8) sub_ddmmss(high_difference, low_difference, high_minuend, low_minuend,
high_subtrahend, low_subtrahend) subtracts two two-word UWtype integers,
composed by HIGH_MINUEND_1 and LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and
LOW_SUBTRAHEND_2 respectively. The result is placed in HIGH_DIFFERENCE
and LOW_DIFFERENCE. Overflow (i.e. carry out) is not stored anywhere,
and is lost.
If any of these macros are left undefined for a particular CPU,
C macros are used. */
/* The CPUs come in alphabetical order below.
Please add support for more CPUs here, or improve the current support
for the CPUs below!
(E.g. WE32100, IBM360.) */
/* Snipped per CPU support */
/* If this machine has no inline assembler, use C macros. */
#if !defined (add_ssaaaa)
#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
do { \
UWtype __x; \
__x = (al) + (bl); \
(sh) = (ah) + (bh) + (__x < (al)); \
(sl) = __x; \
} while (0)
#endif
#if !defined (sub_ddmmss)
#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
do { \
UWtype __x; \
__x = (al) - (bl); \
(sh) = (ah) - (bh) - (__x > (al)); \
(sl) = __x; \
} while (0)
#endif
/* If we lack umul_ppmm but have smul_ppmm, define umul_ppmm in terms of
smul_ppmm. */
#if !defined (umul_ppmm) && defined (smul_ppmm)
#define umul_ppmm(w1, w0, u, v) \
do { \
UWtype __w1; \
UWtype __xm0 = (u), __xm1 = (v); \
smul_ppmm (__w1, w0, __xm0, __xm1); \
(w1) = __w1 + (-(__xm0 >> (W_TYPE_SIZE - 1)) & __xm1) \
+ (-(__xm1 >> (W_TYPE_SIZE - 1)) & __xm0); \
} while (0)
#endif
/* If we still don't have umul_ppmm, define it using plain C. */
#if !defined (umul_ppmm)
#define umul_ppmm(w1, w0, u, v) \
do { \
UWtype __x0, __x1, __x2, __x3; \
UHWtype __ul, __vl, __uh, __vh; \
\
__ul = __ll_lowpart (u); \
__uh = __ll_highpart (u); \
__vl = __ll_lowpart (v); \
__vh = __ll_highpart (v); \
\
__x0 = (UWtype) __ul * __vl; \
__x1 = (UWtype) __ul * __vh; \
__x2 = (UWtype) __uh * __vl; \
__x3 = (UWtype) __uh * __vh; \
\
__x1 += __ll_highpart (__x0);/* this can't give carry */ \
__x1 += __x2; /* but this indeed can */ \
if (__x1 < __x2) /* did we get it? */ \
__x3 += __ll_B; /* yes, add it in the proper pos. */ \
\
(w1) = __x3 + __ll_highpart (__x1); \
(w0) = __ll_lowpart (__x1) * __ll_B + __ll_lowpart (__x0); \
} while (0)
#endif
#if !defined (__umulsidi3)
#define __umulsidi3(u, v) \
({DWunion __w; \
umul_ppmm (__w.s.high, __w.s.low, u, v); \
__w.ll; })
#endif
/* Define this unconditionally, so it can be used for debugging. */
#define __udiv_qrnnd_c(q, r, n1, n0, d) \
do { \
UWtype __d1, __d0, __q1, __q0; \
UWtype __r1, __r0, __m; \
__d1 = __ll_highpart (d); \
__d0 = __ll_lowpart (d); \
\
__r1 = (n1) % __d1; \
__q1 = (n1) / __d1; \
__m = (UWtype) __q1 * __d0; \
__r1 = __r1 * __ll_B | __ll_highpart (n0); \
if (__r1 < __m) \
{ \
__q1--, __r1 += (d); \
if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
if (__r1 < __m) \
__q1--, __r1 += (d); \
} \
__r1 -= __m; \
\
__r0 = __r1 % __d1; \
__q0 = __r1 / __d1; \
__m = (UWtype) __q0 * __d0; \
__r0 = __r0 * __ll_B | __ll_lowpart (n0); \
if (__r0 < __m) \
{ \
__q0--, __r0 += (d); \
if (__r0 >= (d)) \
if (__r0 < __m) \
__q0--, __r0 += (d); \
} \
__r0 -= __m; \
\
(q) = (UWtype) __q1 * __ll_B | __q0; \
(r) = __r0; \
} while (0)
/* If the processor has no udiv_qrnnd but sdiv_qrnnd, go through
__udiv_w_sdiv (defined in libgcc or elsewhere). */
#if !defined (udiv_qrnnd) && defined (sdiv_qrnnd)
#define udiv_qrnnd(q, r, nh, nl, d) \
do { \
USItype __r; \
(q) = __udiv_w_sdiv (&__r, nh, nl, d); \
(r) = __r; \
} while (0)
#endif
/* If udiv_qrnnd was not defined for this processor, use __udiv_qrnnd_c. */
#if !defined (udiv_qrnnd)
#define UDIV_NEEDS_NORMALIZATION 1
#define udiv_qrnnd __udiv_qrnnd_c
#endif
#if !defined (count_leading_zeros)
#define count_leading_zeros(count, x) \
do { \
UWtype __xr = (x); \
UWtype __a; \
\
if (W_TYPE_SIZE <= 32) \
{ \
__a = __xr < ((UWtype)1<<2*__BITS4) \
? (__xr < ((UWtype)1<<__BITS4) ? 0 : __BITS4) \
: (__xr < ((UWtype)1<<3*__BITS4) ? 2*__BITS4 : 3*__BITS4); \
} \
else \
{ \
for (__a = W_TYPE_SIZE - 8; __a > 0; __a -= 8) \
if (((__xr >> __a) & 0xff) != 0) \
break; \
} \
\
(count) = W_TYPE_SIZE - (__clz_tab[__xr >> __a] + __a); \
} while (0)
#define COUNT_LEADING_ZEROS_0 W_TYPE_SIZE
#endif
#if !defined (count_trailing_zeros)
/* Define count_trailing_zeros using count_leading_zeros. The latter might be
defined in asm, but if it is not, the C version above is good enough. */
#define count_trailing_zeros(count, x) \
do { \
UWtype __ctz_x = (x); \
UWtype __ctz_c; \
count_leading_zeros (__ctz_c, __ctz_x & -__ctz_x); \
(count) = W_TYPE_SIZE - 1 - __ctz_c; \
} while (0)
#endif
#ifndef UDIV_NEEDS_NORMALIZATION
#define UDIV_NEEDS_NORMALIZATION 0
#endif