[llvm-dev] Get timestamp and processor ID in the IR

[Hal Finkel via llvm-dev]

----- Original Message -----
> From: "zhi chen" <zchenhn at gmail.com>
> To: "Hal Finkel" <hfinkel at anl.gov>
> Cc: llvm-dev at lists.llvm.org
> Sent: Thursday, November 19, 2015 5:47:45 PM
> Subject: Re: [llvm-dev] Get timestamp and processor ID in the IR
> 
> 
> Say if we have 8 cores, I want to get which core is running the
> current program. Thanks.
> 

What do you intend to do with that information?

One obvious complication is that the identity of the core running your application might change at any time (whenever the operating system performs a context switch). If you need to need to restrict to running only on one core, you'll likely need to adjust the process's core bindings (affinity mask) using some operating-system specific method.

 -Hal

> 
> On Thu, Nov 19, 2015 at 3:37 PM, Hal Finkel < hfinkel at anl.gov >
> wrote:
> 
> 
> ----- Original Message -----
> > From: "zhi chen" < zchenhn at gmail.com >
> > To: "Hal Finkel" < hfinkel at anl.gov >
> > Cc: llvm-dev at lists.llvm.org
> > Sent: Thursday, November 19, 2015 3:48:02 PM
> > Subject: Re: [llvm-dev] Get timestamp and processor ID in the IR
> > 
> > 
> > Hi Hal,
> > 
> > 
> > Thanks for the pointer. Is it possible to get the processor ID on
> > X86
> > architecture? There is a library call in linux, sched_getcpu(), to
> > the ID.
> > 
> 
> What exactly do you mean by "processor ID"?
> 
> -Hal
> 
> 
> 
> > 
> > Also, is it possible to get the program counter in the IR?
> > 
> > 
> > Best,
> > Zhi
> > 
> > 
> > On Thu, Nov 19, 2015 at 1:33 PM, Hal Finkel < hfinkel at anl.gov >
> > wrote:
> > 
> > 
> > Hi Zhi,
> > 
> > There is no standard (architecture-independent) way to get the
> > processor id. We do have an intrinsic to get the cycle counter:
> > 
> > http://llvm.org/docs/LangRef.html#llvm-readcyclecounter-intrinsic
> > 
> > -Hal
> > 
> > 
> > 
> > ----- Original Message -----
> > > From: "zhi chen via llvm-dev" < llvm-dev at lists.llvm.org >
> > > To: llvm-dev at lists.llvm.org
> > > Sent: Thursday, November 19, 2015 3:29:40 PM
> > > Subject: [llvm-dev] Get timestamp and processor ID in the IR
> > > 
> > > 
> > > 
> > > Hi,
> > > 
> > > 
> > > I am wondering if it is possible to get the time-stamp and the
> > > processor ID where an instruction is exectued in the IR? Thanks
> > > for
> > > your help in advance:)
> > > 
> > > 
> > > Best,
> > > Zhi
> > > _______________________________________________
> > > LLVM Developers mailing list
> > > llvm-dev at lists.llvm.org
> > > http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
> > > 
> > 
> > --
> > Hal Finkel
> > Assistant Computational Scientist
> > Leadership Computing Facility
> > Argonne National Laboratory
> > 
> > 
> 
> --
> Hal Finkel
> Assistant Computational Scientist
> Leadership Computing Facility
> Argonne National Laboratory
> 
> 

-- 
Hal Finkel
Assistant Computational Scientist
Leadership Computing Facility
Argonne National Laboratory