[fpc-devel] Question about NOP instructions

J. Gareth Moreton gareth at moreton-family.com
Sat Nov 2 15:08:02 CET 2019

Hi everyone,

During my optimisation travels, I frequently stumble across lone NOP 
instructions in the compiled assembly language.  Normally I leave these 
alone, but occasionally I stumble across things like this:

     movq    $0,24(%rbx)
     movq    %rbp,%rcx

And there are jumps elsewhere that go to one label or the other. Is 
there any reason why a jump should lead to the NOP, or can they all be 
redirected to after the NOP instruction?

Gareth aka. Kit

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