Timeline for LOOP, LOOPE, LOOPNE?
Current License: CC BY-SA 2.5
7 events
| when toggle format | what | by | license | comment | |
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| Sep 4, 2015 at 18:56 | comment | added | golem | Answering my own question. After checking it in gdb I can confirm that none of the loop (LOOP, LOOPE, LOOPNE) instruction affect the ZF flag when they decrement the ECX counter. Now it makes sense. | |
| Sep 4, 2015 at 18:35 | comment | added | golem | @sharptooth, speaking of LOOPE, how after decrementing can ECX be non zero and ZF set? Does LOOPE not affect the ZF flag? | |
| Oct 18, 2013 at 14:14 | comment | added | Johan | @JanusTroelsen, its slower from the 80486 onwards. On the lastest processors it's a lot slower. Source: agner.org/optimize manual #2. | |
| May 18, 2013 at 19:56 | comment | added | Janus Troelsen | @NilsPipenbrinck: On which processors is it slower? What's your source? | |
| Nov 19, 2009 at 18:06 | vote | accept | nunos | ||
| Nov 18, 2009 at 15:23 | comment | added | Nils Pipenbrinck | Also not asked I'd like to point out that all LOOP instructions are much slower than the DEC ECX / JNZ counterpart. This is intended as LOOP should nowadays only be used for delay calibration loops used for hardware-drivers and the like. | |
| Nov 18, 2009 at 14:20 | history | answered | sharptooth | CC BY-SA 2.5 |