[llvm-commits] [llvm] r61934 - in /llvm/trunk: lib/Analysis/ValueTracking.cpp test/Transforms/InstCombine/2009-01-08-AlignAlloca.ll

[Dan Gohman]

On Jan 8, 2009, at 12:48 PM, Chris Lattner wrote:

> On Jan 8, 2009, at 11:45 AM, Dan Gohman wrote:
>>> it will just get the ABI alignment.  This prevents instcombine from
>>> rounding
>>> up the alignment of a load/store without adjusting the alignment of
>>> the alloca.
>>
>> When would a default-alignment Alloca not be given its preferred
>> alignment?
>>
>> Or, if you prefer that instcombine make give all Allocas an explicit
>> alignment, could you add a comment to this code?
>
> InstCombine already has code to handle this (see
> EnforceKnownAlignment).  It isn't catching this case, but it could be
> made to do so if it were important.

Perhaps I was unclear. Is this commit fixing a miscompile?  If so,
it seems that there's a bug elsewhere.  CodeGen ought to be aligning
such Allocas at their preferred alignment.

Dan