Difference between revisions of "Assembler:Commands:LOOP"
| Line 10: | Line 10: | ||
Performs a loop operation using the ECX or CX register as a counter. Each time the LOOP instruction is executed, the count register is decremented, then checked for 0. If the count is 0, the loop is terminated and program execution continues with the instruction following the LOOP instruction. If the count is not zero, a near jump is performed to the destination (target) operand, which is presumably the instruction at the beginning of the loop. If the address-size attribute is 32 bits, the ECX register is used as the count register; otherwise the CX register is used. | Performs a loop operation using the ECX or CX register as a counter. Each time the LOOP instruction is executed, the count register is decremented, then checked for 0. If the count is 0, the loop is terminated and program execution continues with the instruction following the LOOP instruction. If the count is not zero, a near jump is performed to the destination (target) operand, which is presumably the instruction at the beginning of the loop. If the address-size attribute is 32 bits, the ECX register is used as the count register; otherwise the CX register is used. | ||
| + | [http://c9x.me/x86/html/file_module_x86_id_161.html c9x.me/x86/html/file_module_x86_id_161.html] | ||
</div> | </div> | ||
Latest revision as of 15:49, 3 January 2018
command loop operand
The LOOP instruction assumes that the (E)CX register contains the loop count. When the loop instruction is executed, the (E)CX register is decremented and the control jumps to the target label, until the (E)CX register value, i.e., the counter reaches the value zero.
Used for Loop control.
Performs a loop operation using the ECX or CX register as a counter. Each time the LOOP instruction is executed, the count register is decremented, then checked for 0. If the count is 0, the loop is terminated and program execution continues with the instruction following the LOOP instruction. If the count is not zero, a near jump is performed to the destination (target) operand, which is presumably the instruction at the beginning of the loop. If the address-size attribute is 32 bits, the ECX register is used as the count register; otherwise the CX register is used.
Command Parameters[edit]
| Parameter | Description |
|---|---|
| operand | The address or symbol to jump to |
Examples[edit]
label(loop_start) MOV ECX,10 loop_start: // loop body LOOP loop_start
