Файловый менеджер - Редактировать - /usr/src/linux-headers-5.4.0-200/arch/x86/include/asm/div64.h
Назад
/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_DIV64_H #define _ASM_X86_DIV64_H #ifdef CONFIG_X86_32 #include <linux/types.h> #include <linux/log2.h> /* * do_div() is NOT a C function. It wants to return * two values (the quotient and the remainder), but * since that doesn't work very well in C, what it * does is: * * - modifies the 64-bit dividend _in_place_ * - returns the 32-bit remainder * * This ends up being the most efficient "calling * convention" on x86. */ #define do_div(n, base) \ ({ \ unsigned long __upper, __low, __high, __mod, __base; \ __base = (base); \ if (__builtin_constant_p(__base) && is_power_of_2(__base)) { \ __mod = n & (__base - 1); \ n >>= ilog2(__base); \ } else { \ asm("" : "=a" (__low), "=d" (__high) : "A" (n));\ __upper = __high; \ if (__high) { \ __upper = __high % (__base); \ __high = __high / (__base); \ } \ asm("divl %2" : "=a" (__low), "=d" (__mod) \ : "rm" (__base), "0" (__low), "1" (__upper)); \ asm("" : "=A" (n) : "a" (__low), "d" (__high)); \ } \ __mod; \ }) static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder) { union { u64 v64; u32 v32[2]; } d = { dividend }; u32 upper; upper = d.v32[1]; d.v32[1] = 0; if (upper >= divisor) { d.v32[1] = upper / divisor; upper %= divisor; } asm ("divl %2" : "=a" (d.v32[0]), "=d" (*remainder) : "rm" (divisor), "0" (d.v32[0]), "1" (upper)); return d.v64; } #define div_u64_rem div_u64_rem static inline u64 mul_u32_u32(u32 a, u32 b) { u32 high, low; asm ("mull %[b]" : "=a" (low), "=d" (high) : [a] "a" (a), [b] "rm" (b) ); return low | ((u64)high) << 32; } #define mul_u32_u32 mul_u32_u32 #else # include <asm-generic/div64.h> static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 div) { u64 q; asm ("mulq %2; divq %3" : "=a" (q) : "a" (a), "rm" ((u64)mul), "rm" ((u64)div) : "rdx"); return q; } #define mul_u64_u32_div mul_u64_u32_div #endif /* CONFIG_X86_32 */ #endif /* _ASM_X86_DIV64_H */
| ver. 1.4 |
Github
|
.
| PHP 7.4.3-4ubuntu2.24 | Генерация страницы: 0 |
proxy
|
phpinfo
|
Настройка