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Re: How to implement "unsigned long long __rdtsc ()" for x86?
On Fri, Jan 16, 2009 at 11:35 AM, Jack Lloyd <lloyd@randombit.net> wrote:
> According to the info docs, the Alpha has __builtin_alpha_rpcc which
> doesn't take any inputs either, and should just call rpcc much as an
> rdtsc intrinsic would, so it may provide a more direct model.
(define_insn "builtin_rpcc"
[(set (match_operand:DI 0 "register_operand" "=r")
(unspec_volatile:DI [(const_int 0)] UNSPECV_RPCC))]
""
"rpcc %0"
[(set_attr "type" "ilog")])
So yes this is exactly what I was mentioning to do ...
-- Pinski