[llvm-commits] [llvm] r55886 - /llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

[Bill Wendling]

On Mon, Sep 8, 2008 at 1:16 AM, Evan Cheng <evan.cheng at apple.com> wrote:
>
> On Sep 7, 2008, at 5:35 PM, Bill Wendling wrote:
>
>> It's not a bug in that this wasn't being done. I was doing a static
>> analysis of the DAG combiner and noticed that this wasn't doing what
>> the comment claimed it should be doing. If this transformation is
>> performed in the selection DAG code, then it should probably be
>> removed from here entirely (along with the analogous "ADD"
>> transformation). What do you think?
>
> No. The dag combiner xforms can still trigger. The issue is the
> operand can be updated by something like ReplaceAllUsesWith which will
> not transform the uses.
>
Okay, so should the dag combiner transforms be no-ops or actually do something?

-bw