php-src/Zend/zend_multiply.h
2008-12-31 11:15:49 +00:00

61 lines
2.5 KiB
C

/*
+----------------------------------------------------------------------+
| Zend Engine |
+----------------------------------------------------------------------+
| Copyright (c) 1998-2009 Zend Technologies Ltd. (http://www.zend.com) |
+----------------------------------------------------------------------+
| This source file is subject to version 2.00 of the Zend license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.zend.com/license/2_00.txt. |
| If you did not receive a copy of the Zend license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@zend.com so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Sascha Schumann <sascha@schumann.cx> |
| Ard Biesheuvel <ard@ard.nu> |
+----------------------------------------------------------------------+
*/
/* $Id$ */
#if defined(__i386__) && defined(__GNUC__)
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
long __tmpvar; \
__asm__ ("imul %3,%0\n" \
"adc $0,%1" \
: "=r"(__tmpvar),"=r"(usedval) \
: "0"(a), "r"(b), "1"(0)); \
if (usedval) (dval) = (double) (a) * (double) (b); \
else (lval) = __tmpvar; \
} while (0)
#elif SIZEOF_LONG == 4 && defined(HAVE_ZEND_LONG64)
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
zend_long64 __result = (zend_long64) (a) * (zend_long64) (b); \
if (__result > LONG_MAX || __result < LONG_MIN) { \
(dval) = (double) __result; \
(usedval) = 1; \
} else { \
(lval) = (long) __result; \
(usedval) = 0; \
} \
} while (0)
#else
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
long __lres = (a) * (b); \
long double __dres = (long double)(a) * (long double)(b); \
long double __delta = (long double) __lres - __dres; \
if ( ((usedval) = (( __dres + __delta ) != __dres))) { \
(dval) = __dres; \
} else { \
(lval) = __lres; \
} \
} while (0)
#endif