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effective address

The actual memory address an instruction ends up using, after it adds up the registers and numbers in its memory operand.

The effective address is the value computed by an addressing mode (for x86-64, base + index*scale + displacement, modulo 2^64) and used to access memory; lea computes it without accessing memory.

Examples

  • [rbx + rcx*8 + 16] with rbx = 0x1000 and rcx = 2 is 0x1000 + 16 + 16 = 0x1020.

See also

addressing mode displacement scaled index load effective address
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