difference between lea and mov instructions in 8086
assembly language instructionslea x86-64
load effective address definition
LEA instruction The LEA instruction can be used to get the offset address of a Example ORG 100h CLD LEA SI, a1 LEA DI, a2 MOV CX, 5 REP MOVSB RET a1 .. 8-1 ECE 424 Design of Microprocessor-Based Systems Haibo Wang ECE
As others have pointed out, LEA (load effective address) is often used as a “trick” to do certain computations, but that’s not its primary purpose. The x86
Opcode, Instruction, Op/En, 64-Bit Mode, Compat/Leg Mode, Description. 8D /r, LEA r16,m, RM, Valid, Valid, Store effective address for m in register r16.
12 Jun 2017
Description. Computes the effective address of the second operand (the source operand) and stores it in the first operand (destination operand). The source
The lea (Load Effective Address) instruction is identical to an immediate load, with the difference that the same address arithmetic can be used to calculate the constant to be loaded, as for any load/store instruction. The latter is directly translatable into machine code.
Thus, the offset for var, although an immediate value, is not determined until link time. Instruction lea eax, [LocalVar] ; Load effective address of LocalVar into eax29 May 2015 The MOV instruction is a ‘MOVe’ effectively a copy of the address that the TABLE-ADDR label stands for. The LEA instruction is a ‘Load Effective Address’ which is an indirected instruction, which means that TABLE-ADDR points to a memory location at which the address to load is found.
When viewing the registers, it seems the first 2 commands are the same, and then 3rd one puts the value of sample into rcx. I understand there
6 Dec 2014