Re: Is je more effective than jg


<leon800219@xxxxxxxxx> wrote in message
news:1164604928.778784.112080@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

"Ratch дµÀ£º
"
<leon800219@xxxxxxxxx> wrote in message
news:1164592812.095934.170610@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi all:

I wonder is jne more effective than jbe, if so why?

The statement:
for(i=0;i<=10;++i)
{
}
seems slower than:
for(i=0;i!=10;++i)
{
}
?


In the subject of this message you ask about JE. In the body of this
message you ask about JBE. So I am confused. Anyway the question is what
is "effective". JE,JBE, and JG are three different instructions that do
different things. So is addition more "effective" than multiplication or
subtraction? Ratch
Sorry for confusion my question is on JE and JG, by effective I mean
which instruction less time and resouce consuming, since they act like
same functionality in
for loop. Is that make sense?

JE/JNE has to check only one flag (ZF), whereas JG/JLE has to check two
flags (ZF and SF). If the CPU does not have the hardware to check both
flags simultaneously, then JG will be the slower instruction. Ratch


.

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