llvm dev - Apr 2011 - [LLVMdev] bsr not implemented?

Hello,

just trying to use the dragonegg plugin with gcc on my project.
Unfortunately I get an

/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.5.2/include/ia32intrin.h:170:35:
error: unsupported target builtin ‘__builtin_ia32_bsrdi’ used

error. I use (and need) the "bsr" (bit scan reverse) instruction. So
it
seems it isn't implemented (yet). Can I safely use gcc inline assembly
instead? Are the some preprocessor macros defined while using dragonegg
so that I can conditionally compile?

- Gunther

Hi Gunther,
> just trying to use the dragonegg plugin with gcc on my project.
> Unfortunately I get an
>
>
/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.5.2/include/ia32intrin.h:170:35:
> error: unsupported target builtin ‘__builtin_ia32_bsrdi’ used
yup, bsrdi and bsrsi aren't implemented (yet).  Please open a bug report
about
this.  The unimplemented x86 builtins are those commented out in the file
x86/x86_builtins
> error. I use (and need) the "bsr" (bit scan reverse) instruction.
So it
> seems it isn't implemented (yet). Can I safely use gcc inline assembly
> instead?
Yes, inline assembly should work.

  Are the some preprocessor macros defined while using
dragonegg
> so that I can conditionally compile?
No, and I don't think it is possible to add any.  On the other hand
you can always add -DDRAGONEGG or something to your compilation flags
when you are using the plugin.

Ciao, Duncan.