[llvm-commits] [llvm] r148686 - in /llvm/trunk: include/llvm/MC/MCAsmInfo.h lib/CodeGen/AsmPrinter/ARMException.cpp lib/Target/ARM/MCTargetDesc/ARMMCAsmInfo.cpp test/CodeGen/ARM/ehabi-unwind.ll

[Chandler Carruth]

On Sun, Jan 22, 2012 at 11:57 PM, Evgeniy Stepanov <
eugeni.stepanov at gmail.com> wrote:

> Author: eugenis
> Date: Mon Jan 23 01:57:39 2012
> New Revision: 148686
>
> URL: http://llvm.org/viewvc/llvm-project?rev=148686&view=rev
> Log:
> An option to selectively enable parts of ARM EHABI support.
>
> This change adds an new value to the --arm-enable-ehabi option that
> disables emitting unwinding descriptors. This mode gives a working
> backtrace() without the (currently broken) exception support.
>

I've had to revert this in r148759. It violates a very important layering
constraint: the MC library (of which every target's MCTargetDesc
sub-component is a part) must not depend on the CodeGen library. Moving
this flag into CodeGen doesn't work. See my description for more details.

Frankly, I think you stumbled on a much bigger layering problem: if
ARMException.cpp (and related utilities in lib/CodeGen/AsmPrinter) are
needed by various parts of the MC library, they should all be moved down
into the MC library. That's the library resposible for asm printing these
days. I've looped in the MC experts on this thread to provide more insights.

-Chandler
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20120123/3a4d3798/attachment.html>