76 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_MATH64_H
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| #define _LINUX_MATH64_H
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| 
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| #include <linux/types.h>
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| 
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| #ifdef __x86_64__
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| static inline u64 mul_u64_u64_div64(u64 a, u64 b, u64 c)
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| {
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| 	u64 q;
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| 
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| 	asm ("mulq %2; divq %3" : "=a" (q)
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| 				: "a" (a), "rm" (b), "rm" (c)
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| 				: "rdx");
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| 
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| 	return q;
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| }
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| #define mul_u64_u64_div64 mul_u64_u64_div64
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| #endif
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| 
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| #ifdef __SIZEOF_INT128__
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| static inline u64 mul_u64_u32_shr(u64 a, u32 b, unsigned int shift)
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| {
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| 	return (u64)(((unsigned __int128)a * b) >> shift);
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| }
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| 
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| #else
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| 
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| #ifdef __i386__
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| static inline u64 mul_u32_u32(u32 a, u32 b)
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| {
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| 	u32 high, low;
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| 
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| 	asm ("mull %[b]" : "=a" (low), "=d" (high)
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| 			 : [a] "a" (a), [b] "rm" (b) );
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| 
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| 	return low | ((u64)high) << 32;
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| }
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| #else
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| static inline u64 mul_u32_u32(u32 a, u32 b)
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| {
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| 	return (u64)a * b;
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| }
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| #endif
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| 
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| static inline u64 mul_u64_u32_shr(u64 a, u32 b, unsigned int shift)
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| {
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| 	u32 ah, al;
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| 	u64 ret;
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| 
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| 	al = a;
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| 	ah = a >> 32;
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| 
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| 	ret = mul_u32_u32(al, b) >> shift;
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| 	if (ah)
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| 		ret += mul_u32_u32(ah, b) << (32 - shift);
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| 
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| 	return ret;
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| }
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| 
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| #endif	/* __SIZEOF_INT128__ */
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| 
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| #ifndef mul_u64_u64_div64
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| static inline u64 mul_u64_u64_div64(u64 a, u64 b, u64 c)
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| {
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| 	u64 quot, rem;
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| 
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| 	quot = a / c;
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| 	rem = a % c;
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| 
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| 	return quot * b + (rem * b) / c;
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| }
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| #endif
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| 
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| #endif /* _LINUX_MATH64_H */
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