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Re: Scheduling of asm()


>>>>> "Falk" == Falk Hueffner <falk.hueffner@student.uni-tuebingen.de> writes:

 Falk> Hi, When I experimented with some Alpha instructions, I found
 Falk> out there seems to be no way to communicate the scheduling
 Falk> class of an asm() instruction to gcc, leading to somewhat
 Falk> suboptimal code. Would it be reasonably easy to add such a
 Falk> facility? Either the user could mangle it into the asm
 Falk> statement, or gcc could try to parse the string for a known
 Falk> instruction. I would give it a try if somebody tells me whether
 Falk> this is feasible...

I would LOVE to have that for other targets too.

Supplying the schedule class seems like the right answer; it may well
be that you will want to supply an instruction that the compiler would
never issue on its own and therefore has no reason to know about.  An
example valid for MIPS (and for Alpha as well, if I remember
correctly) is the Prefetch instruction.

     paul


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