[cfe-commits] [llvm-commits] [Patch] Move TargetData from Target to Support/VMCore

[Hal Finkel]

On Wed, 26 Sep 2012 21:18:24 -0700
Evan Cheng <evan.cheng at apple.com> wrote:

> 
> 
> On Sep 26, 2012, at 11:07 AM, Hal Finkel <hfinkel at anl.gov> wrote:
> 
> > On Tue, 25 Sep 2012 16:16:22 -0700
> > Evan Cheng <evan.cheng at apple.com> wrote:
> > 
> >> Sorry, I understand why you are requesting this but I thinking
> >> moving TargetData to support is conceptually dirty.
> > 
> > Can you please explain this? I think that the opposite is true:
> > Having TargetData in Target is conceptually dirty. TargetData
> > represents 'target information that is available to frontends and
> > IR-level passes without linking to the target descriptions'.
> 
> Agreed. 
> 
> > As a result, I feel
> > that TargetData does not belong with the target-description
> > infrastructure, and so it should be moved out of Target so that
> > everyone can use it.
> 
> I agree it should be moved out but at least it's target related.
> Polluting Support / VMCore with it is just worse. They have nothing
> to do with target data conceptually.

Good point. On the other hand, TargetData is specified along with
the core IR language reference. Perhaps the problem really is that
auto-upgrade support is in VMCore, and auto-upgrade is full of logic
that deals with target-specific intrinsics (and, maybe soon, pointer
size information). Maybe making a libTargetData would be better?

 -Hal

> This is all a matter of taste.
> I'll let Chris make the decision. 
> 
> Evan
> 
> > 
> >> Nadav is going to
> >> propose a BOF at the DevMeeting to talk about designing an
> >> abstraction to expose target information to LLVM ir.
> > 
> > Great!
> > 
> > Thanks again,
> > Hal
> > 
> >> Can we hold off
> >> this kind of change for now?
> >> 
> >> Losing the ability to verify isn't a strong enough argument for an
> >> immediate change. I don't follow the auto-upgrade argument. Can you
> >> elaborate?
> >> 
> >> Thanks,
> >> 
> >> Evan
> >> 
> >> On Sep 21, 2012, at 4:08 PM, "Villmow, Micah"
> >> <Micah.Villmow at amd.com> wrote:
> >> 
> >>> This time with the actual patch
> >>> 
> >>> From: Villmow, Micah 
> >>> Sent: Friday, September 21, 2012 4:08 PM
> >>> To: llvm-commits at cs.uiuc.edu; cfe-commits at cs.uiuc.edu
> >>> Subject: [Patch] Move TargetData from Target to Support/VMCore
> >>> 
> >>> I have attached a patch which moves TargetData from Target to
> >>> Support/VMCore. The reason why I would like to have this change
> >>> can be read about in more detail in message [1][2], which in turn
> >>> is required for [3]. In short, I need the capability of querying,
> >>> if available, target specific information in the bitcode during
> >>> verifier and the auto-upgrade mechanism. Because TargetData is in
> >>> the target directory, a circular dependency is created when the
> >>> verifier and auto-upgrade mechanism utilize the information.
> >>> Please let me know what you think and if this approach isn't good,
> >>> possible alternate solutions, Micah 
> >>> 
> >>> [1]
> >>> http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-September/053277.html
> >>> [2]
> >>> http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-September/053166.html
> >>> [3]
> >>> http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-August/052639.html
> >>> <move_target_data_to_support_vmcore.txt>_______________________________________________
> >>> llvm-commits mailing list llvm-commits at cs.uiuc.edu
> >>> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
> >> 
> > 
> > 
> > 
> > -- 
> > Hal Finkel
> > Postdoctoral Appointee
> > Leadership Computing Facility
> > Argonne National Laboratory



-- 
Hal Finkel
Postdoctoral Appointee
Leadership Computing Facility
Argonne National Laboratory