Aligned Data Operations

All Alpha systems use the following byte-addressing scheme for aligned data:

• Access to words requires alignment on byte boundaries that are evenly divisible by 2.
  
  
• Access to longwords requires alignment on byte boundaries that are evenly divisible by 4.
  
  
• Access to quadwords requires alignment on byte boundaries that are evenly divisible by 8.

Any attempt to address a data item that does not have the proper alignment may cause an alignment exception.

Aligned data operations include:

Load Quadword (ldq)

Store Quadword (stq)

Load Sign Extended Longword (ldl)

Store Longword (stl)

Load Word (ldw)

Store Word (stw)