Cray CRAY-1 - 056 Ijk Shift (S I ) and (Sj) Left by (Ak) Places to si

i-------------~~-~--~--------------------~-~~--------------~---------,
: 056ijk Shift (Si) and (Sj) left by (Ak) places to S1 :
I I
: 057ijk Shift (Sj) and (S1) right by (Ak) places to S1 :
I I
L ___________________ ~_- ___________ - __ ~ ________________ ______ -- _______ ,
These instructions are executed in the scalar shift unit. They shift
128-bit values fromed by logically joining two S registers. Shift counts
are obtained
from register Ak. A shift of one place occurs if the k
designator
is zero.
All shifts are end-off with zero fill. The shift is effectively a
circular shift if the shift count does not exceed 64 and the i and j
designators are equal
and nonzero. For both the 056 and 057 instructions,
(Sj) are unchanged.
The 056 instruction performs left shifts of (Si) and (Sj) with (Si)
initially the most significant bits of the double register. The high-
order
64 bits of the result are transmitted to Si. Si is cleared if the
shift count exceeds 127. The 056 instruction produces the same result
as the 054 instruction if the shift count does not exceed 63 and the j
designator
is zero.
The 057 instruction performs right shifts of (Sj) and (Si) with (Sj)
initially the most significant bits of the double register. The low-order
64 bits of the result are transmitted to Si. Si is cleared if the shift
count exceeds 127. The 057 instruction produces the same result as the
055 instruction if the shift count does not exceed 63 and the j designator
is zero.
Hold issue conditions
034 - 037 in process
Exchange in process
S register access conflict
Si, Sj, or Ak reserved
Execution time
Si ready 3 CPs
Instruction issue 1 CP
Special cases
(Sj) = 0 if j = 0
(Ak) = 1 if k = 0
2240004
4-39
E