[LLVMbugs] [Bug 23845] New: Apparent miscompilation with BBVectorize and sqrt

[bugzilla-daemon at llvm.org]

https://llvm.org/bugs/show_bug.cgi?id=23845

            Bug ID: 23845
           Summary: Apparent miscompilation with BBVectorize and sqrt
           Product: new-bugs
           Version: 3.6
          Hardware: PC
                OS: Windows NT
            Status: NEW
          Severity: normal
          Priority: P
         Component: new bugs
          Assignee: unassignedbugs at nondot.org
          Reporter: nick at indigorenderer.com
                CC: llvmbugs at cs.uiuc.edu
    Classification: Unclassified

Created attachment 14470
  --> https://llvm.org/bugs/attachment.cgi?id=14470&action=edit
unoptimised IR

In the unoptimised IR there are two calls to wombat326, each of which does a
sqrt. (see wobble211)

In the optimised code there is only one sqrt call.
One sqrt call seems to have been erroneously removed.

Disabling BBVectorize seems to remove the miscompilation.

Optimisation passes are basically the standard -03, with vectorisation passes
enabled.

Platform: LLVM 3.6, windows 64-bit.  Using LLVM for jitting.

Unoptimised IR:
https://gist.github.com/anonymous/55f29c2b165efd66f0a3#file-gistfile1-ll-L98

Optimised IR: https://gist.github.com/anonymous/5029a142fcc946d708a8

-- 
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/20150614/a22c6294/attachment.html>