How to track down a bad llvm optimization pass

[Dan Olson via digitalmars-d-ldc]

Joakim <dlang at joakim.fea.st> writes:

> On Saturday, 18 June 2016 at 15:31:03 UTC, Joakim wrote:
> I just built and linked against llvm 3.7.1 and the problem goes away,
> so it appears that it is a regression in the GVN optimization pass
> with llvm 3.8.0.  I'll check if it goes away with llvm master, and
> file an llvm bug if it doesn't.

And I am trying opposite: builting ldc master against llvm 3.8.0.  See
if I can duplicate the problem.