[fpc-devel] x86 TEST instruction

Thorsten Otto admin at tho-otto.de
Thu Jun 30 12:52:34 CEST 2022

On Montag, 27. Juni 2022 04:43:46 CEST J. Gareth Moreton via fpc-devel wrote:
> testl    $1,%ebx -> testb    $1,%bl

Obviously, thats not the same. The latter will only compare the least-
significant byte against 1, and ignore the rest of the register. The former 
will also compare the remainder of the register against zero. SO you canot do 
such "optimizations" 
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