ASM with other compilers

Marc Glisse marc.glisse at
Mon Mar 7 21:30:17 CET 2011

On Mon, 7 Mar 2011, Torbjorn Granlund wrote:

> Marc Glisse <marc.glisse at> writes:
>  currently, clang refuses to compile jb,pt (x86_64/mod_34lsub1.asm) (it
>  understands jb without ,pt)
> Does "clang" come with its own assembler?

Yes (at least it will in version 2.9).

>  and Oracle refuses movzb
>  (x86_64/gcd_1.asm) (it knows the ...w and ...l versions though).
> Does Oracle accept 'movzbl'?

Yes (as mentioned in the parenthesis).

>  Are those horrible bugs that should absolutely be reported to the
>  compiler vendors, or are there more portable versions of the
>  instructions?
> We should check the critical processors (K8, K10, Core2, NHM, SBR) for
> any slowdowns wrt removing ',pt'.  The insn itself might not be
> affected, but the alignment on subsequent instructions might result in
> unexpected slowdowns.

Ok. I can also report it as a bug and hope it will get fixed soon enough, 
if you think it is a bug (I don't know much about asm).

Marc Glisse

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