ARM: 64 bit operations

Logical shift left by Rn

       ;R0 - least significant word
       ;R1 - most significant word
       ;R2 - shift
       ;Uses R0-R3
       ;7 cycles constant
       mov	r1,r1,lsl r2
       rsb	r3,r2,#32
       orr	r1,1,r0,lsr r3
       mov	r0,r0,lsl r2

Logical shift left by #n

       ;R0 - least significant word
       ;R1 - most significant word
       ;Uses R0-R1
       ;3 cycles constant
       mov	r1,r1,lsl #n
       orr	r1,r1,r0,lsr #32-n
       mov	r0,r0,lsl #n

Logical shift left by 1

       ;R0 - least significant word
       ;R1 - most significant word
       ;Uses R0-R1
       ;2 cycles constant
       adds	r0,r0,r0
       adc	r1,r1,r1

Multiplication