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Addressing ModesAn instruction acts on zero or more operands. The way an instruction accesses its operands is called its Addressing modes.
We can classify the different addressing modes into four groups:
Operands may be implicit or explicit or both. Implicit operands mean that the instruction by definition has some specific operands. These operands are NOT selected by the programmers.
Explicit operands mean the instruction operates on the operands specified by the programmer.
Implicit and explicit operands:
Many Pentium instructions have implicit operands. For instance, most of bit manipulation instructions update the EFLAGS register implicitly. The location of an operand value in memory space is called the effective address (EA) |