explicit operand造句

• Not all machines or individual instructions have explicit operands.
• Some architectures use a particular register as an accumulator in some instructions, but other instructions use register numbers for explicit operand specification.
• Special purpose instructions also often lack explicit operands ( CPUID in the x86 architecture writes values into four implicit destination registers, for instance ).
• A good code optimizer can track implicit as well as explicit operands which may allow more frequent constant propagation, constant folding of registers ( a register assigned the result of a constant expression freed up by replacing it by that constant ) and other code enhancements.