Branch Instructions
Conditional branch instructions can test a register for positive/negative or for zero/nonzero, and they can test integer registers for even/odd. Unconditional branch instructions can write a return address into a register.
There is also a calculated jump instruction that branches to an arbitrary
Load/Store Instructions
Load and store instructions move
The VAX
A
Compilers, as directed by user declarations, can generate any mixture of
Integer Operate Instructions
The integer operate instructions manipulate full
There are just three
There is no integer divide instruction.
The Alpha architecture also supports the following additional operations:
•Scaled add/subtract instructions for quick subscript calculation
•
•Conditional move instructions for avoiding branch instructions
•An extensive set of
•A set of multimedia instructions that support graphics and video
Integer overflow trap enable is encoded in the function field of each instruction, rather than kept in a global state bit. Thus, for example, both ADDQ/V and ADDQ opcodes exist for spec- ifying
Introduction
