[llvm-dev] Folding zext from i1 into PHI nodes with only zwo incoming values.

Daniel Berlin via llvm-dev llvm-dev at lists.llvm.org
Tue Jan 31 06:06:30 PST 2017

On Mon, Jan 30, 2017 at 1:22 PM, Sanjay Patel <spatel at rotateright.com>

> Hi Björn and Daniel,
> FoldPHIArgOpIntoPHI() is for unary ops (casts), but it calls
> FoldPHIArgBinOpIntoPHI() for binops which takes care of almost everything
> else?

FWIW: It seems like it tries to restrict itself to certain cases (single
use) but i can still pretty easily produce a testcase where it would
require an exponential number of applications.

That said, hasn't triggered so far for folks, so \_(ツ)_/¯
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20170131/eaf558b2/attachment.html>

More information about the llvm-dev mailing list