The builtin function `__builtin_ia32_rdtscp()` is undocumented

Marc Glisse
Mon Apr 24 06:29:00 GMT 2017

On Mon, 24 Apr 2017, Liu Hao wrote:

> Today I accidentally found the built-in function `__builtin_ia32_rdtscp()` on 
> GCC6, but there is no documentation about it on 
> <>. Is this an 
> oversight?

I don't know if it is an oversight, but I think documenting the builtins 
is a bad idea, you are supposed to use the intrinsics instead, in this 
case __rdtscp, which is documented by Intel (and Microsoft).

Marc Glisse

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