Difference between revisions of "ARM: 64 bit operations"
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(New page: 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 r...) |
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| − | Logical shift left by Rn | + | ==Logical shift left by Rn (0-32)== |
;R0 - least significant word | ;R0 - least significant word | ||
;R1 - most significant word | ;R1 - most significant word | ||
| Line 11: | Line 11: | ||
| − | Logical shift left by #n | + | ==Logical shift left by Rn (0-64)== |
| + | ;R0 - least significant word | ||
| + | ;R1 - most significant word | ||
| + | ;R2 - shift | ||
| + | ;Uses R0-R3 | ||
| + | ; 8-9 cycles | ||
| + | rsbs r3,r2,#32 | ||
| + | submi r3,r2,#32 | ||
| + | movmi r1,r0,lsl r3 | ||
| + | movpl r1,r1,lsl r2 | ||
| + | orrpl r1,r1,r0,lsr r3 | ||
| + | mov r0,r0,lsl r2 | ||
| + | |||
| + | |||
| + | ==Logical shift left by #n (0-32)== | ||
;R0 - least significant word | ;R0 - least significant word | ||
;R1 - most significant word | ;R1 - most significant word | ||
| Line 21: | Line 35: | ||
| − | Logical shift left by 1 | + | ==Logical shift left by #n (33-64)== |
| + | ;R0 - least significant word | ||
| + | ;R1 - most significant word | ||
| + | ;Uses R0-R1 | ||
| + | ;2 cycles constant | ||
| + | mov r1,r0,lsl #n-32 | ||
| + | mov r0,#0 | ||
| + | |||
| + | |||
| + | ==Logical shift left by 1== | ||
;R0 - least significant word | ;R0 - least significant word | ||
;R1 - most significant word | ;R1 - most significant word | ||
| Line 30: | Line 53: | ||
| − | + | == Test for zero == | |
| + | ;R0 - least significant word | ||
| + | ;R1 - most significant word | ||
| + | ;Uses R0-R2 | ||
| + | ;1 cycle constant | ||
| + | orrs r2,r1,r0 | ||
[[Category:Computing]] | [[Category:Computing]] | ||
Latest revision as of 14:54, 23 March 2008
Contents
Logical shift left by Rn (0-32)
;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 Rn (0-64)
;R0 - least significant word
;R1 - most significant word
;R2 - shift
;Uses R0-R3
; 8-9 cycles
rsbs r3,r2,#32
submi r3,r2,#32
movmi r1,r0,lsl r3
movpl r1,r1,lsl r2
orrpl r1,r1,r0,lsr r3
mov r0,r0,lsl r2
Logical shift left by #n (0-32)
;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 #n (33-64)
;R0 - least significant word
;R1 - most significant word
;Uses R0-R1
;2 cycles constant
mov r1,r0,lsl #n-32
mov r0,#0
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
Test for zero
;R0 - least significant word
;R1 - most significant word
;Uses R0-R2
;1 cycle constant
orrs r2,r1,r0
