[fpc-devel] Question about NOP instructions

[J. Gareth Moreton]

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)
.Lj1859:
     nop
.Lj1858:
     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