[llvm-commits] Patch to safely restore optimization to testcase from PR3225 on x86

[Dan Gohman]

On Dec 18, 2008, at 9:49 PM, Duncan Sands wrote:

> On Friday 19 December 2008 02:31:13 Dan Gohman wrote:
>>> +  if (KnownZero == VTBits) {
>>
>> If the shift count is known to be all-zero, shouldn't it
>> have been simplified already by pre-legalize DAGCombine,
>> if not InstCombine?
>
> What if it was introduced by LegalizeTypes itself?

It turns out I had misread the code.  But even if it had been this
way, we now run DAGCombine between LegalizeTypes and
LegalizeOps(?) so it should still catch this :-).

Dan