[llvm-bugs] [Bug 17854] Vectorizer produces wrong code (div by zero)

via llvm-bugs llvm-bugs at lists.llvm.org
Tue Dec 1 15:48:05 PST 2015


https://llvm.org/bugs/show_bug.cgi?id=17854

Sanjay Patel <spatel+llvm at rotateright.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |spatel+llvm at rotateright.com
           See Also|                            |https://llvm.org/bugs/show_
                   |                            |bug.cgi?id=25572,
                   |                            |https://llvm.org/bugs/show_
                   |                            |bug.cgi?id=8100,
                   |                            |https://llvm.org/bugs/show_
                   |                            |bug.cgi?id=6050
         Resolution|---                         |INVALID

--- Comment #5 from Sanjay Patel <spatel+llvm at rotateright.com> ---
The program has undefined behavior because it uses feenableexcept() without
#pragma STDC FENV_ACCESS ON. If there's no warning for that, that seems like a
worthy but different bug.

See bug 25572, comment 5 for more details about the pragma.

Clang doesn't support changing the FP env (bug 8100), so it assumes that FP ops
have no side effects (bug 6050).

...but there's some hope this will improve:
http://reviews.llvm.org/D14067

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20151201/85f5a63b/attachment.html>


More information about the llvm-bugs mailing list