include/linux/math64.h

8 #if BITS_PER_LONG == 64
14  * div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder
16  * This is commonly provided by 32bit archs to provide an optimized 64bit
26  * div_s64_rem - signed 64bit divide with 32bit divisor with remainder
35  * div64_u64_rem - unsigned 64bit divide with 64bit divisor and remainder
44  * div64_u64 - unsigned 64bit divide with 64bit divisor
52  * div64_s64 - signed 64bit divide with 64bit divisor
91  * div_u64 - unsigned 64bit divide with 32bit divisor
93  * This is the most common 64bit divide and should be used if possible,
94  * as many 32bit archs can optimize this variant better than a full 64bit
106  * div_s64 - signed 64bit divide with 32bit divisor
128 		dividend -= divisor;  in __iter_div_u64_rem()
139  * Many a GCC version messes this up and generates a 64x64 mult :-(
176 		ret += mul_u32_u32(ah, mul) << (32 - shift);  in mul_u64_u32_shr()
206 	 * Each of these lines computes a 64-bit intermediate result into "c",  in mul_u64_u64_shr()
207 	 * starting at bits 32-95.  The low 32-bits go into the result of the  in mul_u64_u64_shr()
208 	 * multiplication, the high 32-bits are carried into the next step.  in mul_u64_u64_shr()
215 	 * The 128-bit result of the multiplication is in rl.ll and rh.ll,  in mul_u64_u64_shr()
220 	if (shift < 64)  in mul_u64_u64_shr()
221 		return (rl.ll >> shift) | (rh.ll << (64 - shift));  in mul_u64_u64_shr()
246 	/* Bits 32-63 of the result will be in rh.l.low. */  in mul_u64_u32_div()
249 	/* Bits 0-31 of the result will be in rl.l.low.	*/  in mul_u64_u32_div()