Viewing file:  zend_multiply.h (9.75 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
+----------------------------------------------------------------------+
| Zend Engine |
+----------------------------------------------------------------------+
| Copyright (c) 1998-2018 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.biesheuvel@linaro.org> |
+----------------------------------------------------------------------+
*/
#include "zend_portability.h"
#ifndef ZEND_MULTIPLY_H
#define ZEND_MULTIPLY_H
#if PHP_HAVE_BUILTIN_SMULL_OVERFLOW && SIZEOF_LONG == SIZEOF_ZEND_LONG
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
long __tmpvar; \
if (((usedval) = __builtin_smull_overflow((a), (b), &__tmpvar))) { \
(dval) = (double) (a) * (double) (b); \
} \
else (lval) = __tmpvar; \
} while (0)
#elif PHP_HAVE_BUILTIN_SMULLL_OVERFLOW && SIZEOF_LONG_LONG == SIZEOF_ZEND_LONG
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
long long __tmpvar; \
if (((usedval) = __builtin_smulll_overflow((a), (b), &__tmpvar))) { \
(dval) = (double) (a) * (double) (b); \
} \
else (lval) = __tmpvar; \
} while (0)
#elif (defined(__i386__) || defined(__x86_64__)) && defined(__GNUC__)
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
zend_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 defined(__arm__) && defined(__GNUC__)
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
zend_long __tmpvar; \
__asm__("smull %0, %1, %2, %3\n" \
"sub %1, %1, %0, asr #31" \
: "=r"(__tmpvar), "=r"(usedval) \
: "r"(a), "r"(b)); \
if (usedval) (dval) = (double) (a) * (double) (b); \
else (lval) = __tmpvar; \
} while (0)
#elif defined(__aarch64__) && defined(__GNUC__)
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
zend_long __tmpvar; \
__asm__("mul %0, %2, %3\n" \
"smulh %1, %2, %3\n" \
"sub %1, %1, %0, asr #63\n" \
: "=&r"(__tmpvar), "=&r"(usedval) \
: "r"(a), "r"(b)); \
if (usedval) (dval) = (double) (a) * (double) (b); \
else (lval) = __tmpvar; \
} while (0)
#elif defined(ZEND_WIN32)
# ifdef _M_X64
# pragma intrinsic(_mul128)
# define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
__int64 __high; \
__int64 __low = _mul128((a), (b), &__high); \
if ((__low >> 63I64) == __high) { \
(usedval) = 0; \
(lval) = __low; \
} else { \
(usedval) = 1; \
(dval) = (double)(a) * (double)(b); \
} \
} while (0)
# else
# define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
zend_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
#elif defined(__powerpc64__) && defined(__GNUC__)
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
long __low, __high; \
__asm__("mulld %0,%2,%3\n\t" \
"mulhd %1,%2,%3\n" \
: "=&r"(__low), "=&r"(__high) \
: "r"(a), "r"(b)); \
if ((__low >> 63) != __high) { \
(dval) = (double) (a) * (double) (b); \
(usedval) = 1; \
} else { \
(lval) = __low; \
(usedval) = 0; \
} \
} while (0)
#elif SIZEOF_ZEND_LONG == 4
#define ZEND_SIGNED_MULTIPLY_LONG(a, b, lval, dval, usedval) do { \
int64_t __result = (int64_t) (a) * (int64_t) (b); \
if (__result > ZEND_LONG_MAX || __result < ZEND_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
#if defined(__GNUC__) && (defined(__native_client__) || defined(i386))
static zend_always_inline size_t zend_safe_address(size_t nmemb, size_t size, size_t offset, int *overflow)
{
size_t res = nmemb;
size_t m_overflow = 0;
if (ZEND_CONST_COND(offset == 0, 0)) {
__asm__ ("mull %3\n\tadcl $0,%1"
: "=&a"(res), "=&d" (m_overflow)
: "%0"(res),
"rm"(size));
} else {
__asm__ ("mull %3\n\taddl %4,%0\n\tadcl $0,%1"
: "=&a"(res), "=&d" (m_overflow)
: "%0"(res),
"rm"(size),
"rm"(offset));
}
if (UNEXPECTED(m_overflow)) {
*overflow = 1;
return 0;
}
*overflow = 0;
return res;
}
#elif defined(__GNUC__) && defined(__x86_64__)
static zend_always_inline size_t zend_safe_address(size_t nmemb, size_t size, size_t offset, int *overflow)
{
size_t res = nmemb;
zend_ulong m_overflow = 0;
#ifdef __ILP32__ /* x32 */
# define LP_SUFF "l"
#else /* amd64 */
# define LP_SUFF "q"
#endif
if (ZEND_CONST_COND(offset == 0, 0)) {
__asm__ ("mul" LP_SUFF " %3\n\t"
"adc $0,%1"
: "=&a"(res), "=&d" (m_overflow)
: "%0"(res),
"rm"(size));
} else {
__asm__ ("mul" LP_SUFF " %3\n\t"
"add %4,%0\n\t"
"adc $0,%1"
: "=&a"(res), "=&d" (m_overflow)
: "%0"(res),
"rm"(size),
"rm"(offset));
}
#undef LP_SUFF
if (UNEXPECTED(m_overflow)) {
*overflow = 1;
return 0;
}
*overflow = 0;
return res;
}
#elif defined(__GNUC__) && defined(__arm__)
static zend_always_inline size_t zend_safe_address(size_t nmemb, size_t size, size_t offset, int *overflow)
{
size_t res;
zend_ulong m_overflow;
__asm__ ("umlal %0,%1,%2,%3"
: "=r"(res), "=r"(m_overflow)
: "r"(nmemb),
"r"(size),
"0"(offset),
"1"(0));
if (UNEXPECTED(m_overflow)) {
*overflow = 1;
return 0;
}
*overflow = 0;
return res;
}
#elif defined(__GNUC__) && defined(__aarch64__)
static zend_always_inline size_t zend_safe_address(size_t nmemb, size_t size, size_t offset, int *overflow)
{
size_t res;
zend_ulong m_overflow;
__asm__ ("mul %0,%2,%3\n\tumulh %1,%2,%3\n\tadds %0,%0,%4\n\tadc %1,%1,xzr"
: "=&r"(res), "=&r"(m_overflow)
: "r"(nmemb),
"r"(size),
"r"(offset));
if (UNEXPECTED(m_overflow)) {
*overflow = 1;
return 0;
}
*overflow = 0;
return res;
}
#elif defined(__GNUC__) && defined(__powerpc64__)
static zend_always_inline size_t zend_safe_address(size_t nmemb, size_t size, size_t offset, int *overflow)
{
size_t res;
unsigned long m_overflow;
__asm__ ("mulld %0,%2,%3\n\t"
"mulhdu %1,%2,%3\n\t"
"addc %0,%0,%4\n\t"
"addze %1,%1\n"
: "=&r"(res), "=&r"(m_overflow)
: "r"(nmemb),
"r"(size),
"r"(offset));
if (UNEXPECTED(m_overflow)) {
*overflow = 1;
return 0;
}
*overflow = 0;
return res;
}
#elif SIZEOF_SIZE_T == 4
static zend_always_inline size_t zend_safe_address(size_t nmemb, size_t size, size_t offset, int *overflow)
{
uint64_t res = (uint64_t) nmemb * (uint64_t) size + (uint64_t) offset;
if (UNEXPECTED(res > UINT64_C(0xFFFFFFFF))) {
*overflow = 1;
return 0;
}
*overflow = 0;
return (size_t) res;
}
#else
static zend_always_inline size_t zend_safe_address(size_t nmemb, size_t size, size_t offset, int *overflow)
{
size_t res = nmemb * size + offset;
double _d = (double)nmemb * (double)size + (double)offset;
double _delta = (double)res - _d;
if (UNEXPECTED((_d + _delta ) != _d)) {
*overflow = 1;
return 0;
}
*overflow = 0;
return res;
}
#endif
static zend_always_inline size_t zend_safe_address_guarded(size_t nmemb, size_t size, size_t offset)
{
int overflow;
size_t ret = zend_safe_address(nmemb, size, offset, &overflow);
if (UNEXPECTED(overflow)) {
zend_error_noreturn(E_ERROR, "Possible integer overflow in memory allocation (%zu * %zu + %zu)", nmemb, size, offset);
return 0;
}
return ret;
}
/* A bit more generic version of the same */
static zend_always_inline size_t zend_safe_addmult(size_t nmemb, size_t size, size_t offset, const char *message)
{
int overflow;
size_t ret = zend_safe_address(nmemb, size, offset, &overflow);
if (UNEXPECTED(overflow)) {
zend_error_noreturn(E_ERROR, "Possible integer overflow in %s (%zu * %zu + %zu)", message, nmemb, size, offset);
return 0;
}
return ret;
}
#endif /* ZEND_MULTIPLY_H */
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* indent-tabs-mode: t
* End:
* vim600: sw=4 ts=4 fdm=marker
* vim<600: sw=4 ts=4
*/
|