[GitHub/mt8127/android_kernel_alcatel_ttab.git] / include / asm-x86 / div64.h

#ifndef ASM_X86__DIV64_H
#define ASM_X86__DIV64_H

#ifdef CONFIG_X86_32

#include <linux/types.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);					\
	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

#else
# include <asm-generic/div64.h>
#endif /* CONFIG_X86_32 */

#endif /* ASM_X86__DIV64_H */
Commit	Line	Data
77ef50a5 VN	1	#ifndef ASM_X86__DIV64_H
77ef50a5 VN	2	#define ASM_X86__DIV64_H
428c5a23	3
96a388de	4	#ifdef CONFIG_X86_32
428c5a23 CS	5
	6	#include <linux/types.h>
	7
	8	/*
	9	* do_div() is NOT a C function. It wants to return
	10	* two values (the quotient and the remainder), but
	11	* since that doesn't work very well in C, what it
	12	* does is:
	13	*
	14	* - modifies the 64-bit dividend _in_place_
	15	* - returns the 32-bit remainder
	16	*
	17	* This ends up being the most efficient "calling
	18	* convention" on x86.
	19	*/
925a09b2 JP	20	#define do_div(n, base) \
	21	({ \
	22	unsigned long __upper, __low, __high, __mod, __base; \
	23	__base = (base); \
	24	asm("":"=a" (__low), "=d" (__high) : "A" (n)); \
	25	__upper = __high; \
	26	if (__high) { \
	27	__upper = __high % (__base); \
	28	__high = __high / (__base); \
	29	} \
	30	asm("divl %2":"=a" (__low), "=d" (__mod) \
	31	: "rm" (__base), "0" (__low), "1" (__upper)); \
	32	asm("":"=A" (n) : "a" (__low), "d" (__high)); \
	33	__mod; \
428c5a23 CS	34	})
428c5a23 CS	35
2418f4f2 RZ	36	static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
	37	{
	38	union {
	39	u64 v64;
	40	u32 v32[2];
	41	} d = { dividend };
	42	u32 upper;
	43
	44	upper = d.v32[1];
	45	d.v32[1] = 0;
	46	if (upper >= divisor) {
	47	d.v32[1] = upper / divisor;
	48	upper %= divisor;
	49	}
	50	asm ("divl %2" : "=a" (d.v32[0]), "=d" (*remainder) :
	51	"rm" (divisor), "0" (d.v32[0]), "1" (upper));
	52	return d.v64;
	53	}
	54	#define div_u64_rem div_u64_rem
	55
96a388de	56	#else
428c5a23 CS	57	# include <asm-generic/div64.h>
	58	#endif /* CONFIG_X86_32 */
	59
77ef50a5	60	#endif /* ASM_X86__DIV64_H */