Différences

Ci-dessous, les différences entre deux révisions de la page.

--- back2root:ibm-pc-ms-dos:asm:instr:rep [2023/01/20 21:10] – frater
+++ back2root:ibm-pc-ms-dos:instr:rep [2023/02/24 14:16] – supprimée - modification externe (Unknown date) 127.0.0.1
@@ Ligne 1: / Ligne 1: @@
-====== REP ======
-===== REP - Repeat String Operation =====
-Repeats execution of string instructions while CX != 0. After each string operation, CX is decremented and the Zero Flag is tested.
-**Usage:**
-<code asm>
-	REP MOVSB
-</code>
-The combination of a repeat prefix and a segment override on CPU's before the 386 may result in errors if an interrupt occurs before CX=0. The following code shows code that is susceptible to this and how to avoid it:
-<code asm>
-again:	rep movs	byte ptr ES:[DI],ES:[SI]	; vulnerable instr.
-	jcxz		next				; continue if REP successful
-	loop		again				; interrupt goofed count
-next:
-</code>
-**Modifies flags:**
-<WRAP round box>
-None
-</WRAP>
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-{{page>:back2root:ibm-pc-ms-dos:asm:instr:see-footer}}