Green shading in the line number column means the source is part of the translation unit, red means it is conditionally excluded. Highlighted line numbers link to the translation unit page. Highlighted macros link to the macro page.
1: #ifndef _ASM_GENERIC_DIV64_H 2: #define _ASM_GENERIC_DIV64_H 3: /* 4: * Copyright (C) 2003 Bernardo Innocenti <bernie@develer.com> 5: * Based on former asm-ppc/div64.h and asm-m68knommu/div64.h 6: * 7: * The semantics of do_div() are: 8: * 9: * uint32_t do_div(uint64_t *n, uint32_t base) 10: * { 11: * uint32_t remainder = *n % base; 12: * *n = *n / base; 13: * return remainder; 14: * } 15: * 16: * NOTE: macro parameter n is evaluated multiple times, 17: * beware of side effects! 18: */ 19: 20: #include <linux/types.h> 21: #include <linux/compiler.h> 22: 23: #if BITS_PER_LONG == 64 24: 25: # define do_div(n,base) ({ \ 26: uint32_t __base = (base); \ 27: uint32_t __rem; \ 28: __rem = ((uint64_t)(n)) % __base; \ 29: (n) = ((uint64_t)(n)) / __base; \ 30: __rem; \ 31: }) 32: 33: #elif BITS_PER_LONG == 32 34: 35: extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor); 36: 37: /* The unnecessary pointer compare is there 38: * to check for type safety (n must be 64bit) 39: */ 40: # define do_div(n,base) ({ \ 41: uint32_t __base = (base); \ 42: uint32_t __rem; \ 43: (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \ 44: if (likely(((n) >> 32) == 0)) { \ 45: __rem = (uint32_t)(n) % __base; \ 46: (n) = (uint32_t)(n) / __base; \ 47: } else \ 48: __rem = __div64_32(&(n), __base); \ 49: __rem; \ 50: }) 51: 52: #else /* BITS_PER_LONG == ?? */ 53: 54: # error do_div() does not yet support the C64 55: 56: #endif /* BITS_PER_LONG */ 57: 58: #endif /* _ASM_GENERIC_DIV64_H */ 59: