[llvm-commits] [llvm] r78295 - in /llvm/trunk: lib/CodeGen/SelectionDAG/DAGCombiner.cpp test/CodeGen/X86/wide-integer-fold.ll

[Duncan Sands]

Hi Dan,

>> this is not a problem with your patch, but I notice that this part
>> of the DAG combiner seems to make a lot of unsafe use of get?ExtValue.
>> Any chance of adding this to your TODO list? :)
> 
> I scanned through all of DAGCombiner and fixed all the cases I
> found where getZExtValue was used for a purpose other than a
> shift count. For shift counts, values that don't fit in 64 bits
> are fairly rare ;-), so it's not a high priority. If I missed
> any places, I'd be happy to be shown them.

I just went through DAGCombiner and couldn't find any examples
either.  I misread the uses of getZExtValue visible in your
patch: they weren't for the transform I thought they were for,
they were shift amounts.  Sorry for the noise.

Ciao,

Duncan.