C/C++ call to detect cpu?

Garrett Cooper youshi10 at u.washington.edu
Sat Jan 21 18:26:28 PST 2006

On Jan 21, 2006, at 12:33 PM, John Levine wrote:

>> Other than 'grep'ing dmesg, is there a way to know the current cpu  
>> such as a
>> struct with the machine's cpu and cpu feature (kinda like a time_t  
>> struct)?
> $ sysctl hw.model
> hw.model: AMD Athlon(tm) 64 Processor 3000+
> If you want more details write a tiny assembler routine that does a
> CPUID instruction and decode the result.  Intel has a detailed  
> application
> note about it at
> http://developer.intel.ru/design/xeon/applnots/241618.htm
> R's,
> John

	As for gcc, CFLAGS and CXXFLAGS, doing some searching on google for  
"-march" gcc will prove to help you in finding out what is and is not  
supported by your processor. There's also a link from the Gentoo  
Linux docs somewhere in the handbook, but you will have to hunt that  
down on your own ;).
	There's also a better (or perhaps, just more relevant) doc somewhere  
on FreeBSD's site about CFLAGS and CXXFLAGS which also addresses gcc  
variables and architectures I think.

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