test eax, eax - why?

From: spamtrap@xxxxxxxxxx
Date: 24 Aug 2006 07:41:06 -0700

Hi everyone,
I'm trying to learn x86 assembly language, and in addition to reading
the necessary books, trying the programmes etc., I'm also compiling my
own example C code and comparing it with the resultant (Visual C++)
code.

One thing I tried was compiling the "infinite" while(1){ ... } loop. I
got something like this:

mov eax, 1
test eax, eax
je label2

this seems somewhat odd. I know that "test" does a bitwise and of eax
and eax, but in this case, the rest of the
instruction (je) is not carried out. Why bother with this at all? Or
have I got the wrong end of the stick?

TIA

Paul

.

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- Re: test eax, eax - why?
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