They also provide access to SPRs and DCRs. Instructions Table 2 lists different instruction categories, and the types of instructions that exist in that category. Instructions are first decoded by the upper 6 bits, in a field called the primary opcode. Operands can be registers or immediate values. Many instructions exist for performing arithmetic operations, including add, subtract, negation, compare, multiply and divide.
Many forms exist for immediate values, overflow detection, and carry in and out.
Multiply and divide instruction performance varies among implementations, as these are typically multi-cycle instructions. Logical Instructions Table 3. PowerPC Logical Instructions AND OR Exclusive OR Rotate and Mask Shift Misc. Table 3 lists PowerPC logical instructions. PowerPC has the ability to perform a 32-bit rotate and combine with a mask in a single cycle.