Re: nasm over gas?

[Jamie Lokier]

Eric W. Biederman wrote:
> Actually it is no as simple as that.  With the instruction that uses
> %edi following immediately after the instruction that populates it you cannot
> execute those two instructions in parallel.  So the code may be slower.  The
> exact rules depend on the architecture of the cpu.

I remember inserting a "nop" into a loop and it went significantly
faster on a Pentium Pro :)

> If you concentrate on those handful of places where you need to
> optimize that is reasonable.  Beyond that there simply are not the
> developer resources to do good assembly.  And things like algorithmic
> transformations in assembly are an absolute nightmare.  Where they are
> quite simple in C.

If we had enough developer resources to write the whole thing in good
assembly, then for _sure_ we'd have enough to write a perfect compiler!

I would argue that the most powerful algorithmic transformations are a
nightmare in C, too.  Less so, though.

-- Jamie
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