Cray pointers can be assigned values as follows:
Set to an absolute address
Example: q = 0
Assigned to or from integer variables, plus or minus expressions
Example: p = q + 100
Cray pointers are not integers. You cannot assign them to a real variable.
The LOC function (nonstandard) can be used to define a Cray pointer.
Example: p = LOC( x )
Example: Use Cray pointers as described above.
SUBROUTINE sub ( n )
COMMON pool(100000)
INTEGER blk(128), word64
REAL a(1000), b(n), c(100000-n-1000)
POINTER ( pblk, blk ), (ia, a ), ( ib, b ), &
( ic, c ), ( address, word64 )
DATA address / 64 /
pblk = 0
ia = LOC( pool )
ib = ia + 4000
ic = ib + n
...Remarks about the above example:
word64 refers to the contents of absolute address 64
blk is an array that occupies the first 128 words of memory
a is an array of length 1000 located in blank common
b follows a and is of length n
c follows b
a, b, and c are associated with pool
word64 is the same as blk(17) because Cray pointers are byte address and the integer elements of blk are each 4 bytes long