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3.5 Arithmetic and logical operation

In fact, in addition to the first LEADL, these instructions have a variant with operands, but omitted here, such as add can be addb, ADDW and Addl.

3.5.1 Load Valid address

The command Leal (load effective address) is actually a variant of MOVL, but there is one obvious feature that he actually does not really refer to memory. For example Leal 7 (%edx,%edx, 4),%edx, assuming that the value inside the%edx is x, then the meaning here is not to take the 5x+7 as the address to get the value and then back to the%eax, but simply to 5x+7 exist in%eax ... At the same time the object operand of the instruction (rightmost) must be a register.

3.5.21 Yuan operation and two Yuan operation

Machine-level representation of the program (1)