Basic Instruction Features

All instructions share some basic features. This section describes the fields in the base instruction class. Other classes are derived from the instruction class to include fields that are specific to the different instruction formats.

Besides the features below, the instructions have ID numbers that can be used to identify them across passes of the compiler. This is discussed in detail elsewhere. See section ID Numbers for Tree Nodes and Instructions.

The SUIF library also declares an instruction_list class for working with lists of pointers to instructions. This class is not used much within the library itself because SUIF does not store instructions directly on lists. Even with the flat list form, the instructions are contained in tree_instr nodes, which in turn are stored in lists. However, it may sometimes be convenient to work with lists of instruction pointers even if those instructions are actually stored in tree_instr nodes.

• Opcodes and Formats: Description of opcode and format enumerations.
• Destination Operands: Conventions for the destination operands.
• Result Types: Specifying the types of the result values.
• Parent Tree Nodes: Back-pointers to the tree_instr nodes.
• Source Operands: Standard methods for accessing sources.
• Printing Methods: Printing instructions and operands as text.