LEAL: leal S, D ? ?-> ? ?D ← &S

在 CSAPP (Computer Systems: A Programmer’s Perspective) 中，對 LEAL 指令用作簡單算術運算的情況，給出了一個例子：

For example, if register %edx contains value x, leal 7(%edx,%edx,4), %eax will set register %eax to 5x + 7.

正確理解邏輯為：

1. 設%edx的值為x

2. 7(%edx,%edx,4) 為變質尋址，目標內存地址為5x+7

3. 設儲存在地址5x+7的值為y。然而LEAL并不尋址，它只取y的地址。y的地址即為5x+7。因此，LEAL的左操作數為5x+7

CSAPP描述為:

It has the form of an instruction that reads from memory to a register, but it does not reference memory at all. Its first operand appears to be a memory reference, but instead of reading from the designated location, the instruction copies the effective address to the destination.

4. LEAL將y的地址，5x+7，賦給%eax

至此，LEAL實現了簡單算術功能。