ALIGNED Clause

Parallel Directive Clause: Specifies that all variables in a list are aligned.

ALIGNED (list [:n])

list	Is the name of one or more variables. Each name must be separated by a comma. Any variable that appears in `list` cannot appear in more than one ALIGNED clause.
n	Must be a constant positive integer expression; it indicates the number of bytes for the alignment. If `n` is not specified, the compiler uses the default alignment specified for SIMD instructions on the target platform.

The ALIGNED clause overrides efficiency heuristics in the optimizer. It instructs the compiler to use aligned data movement instructions for all array references. This clause disables all the advanced alignment optimizations of the compiler, such as determining alignment properties from the program context or using dynamic loop peeling to make references aligned.

Note

Be careful when using the ALIGNED clause. Instructing the compiler to implement all array references with aligned data movement instructions will cause a runtime exception if some of the access patterns are actually unaligned.