[PATCH] Allow CodeGen to take advantage of functions that always return arguments

[Stephen Lin]

It won't apply cleanly without the dependency, actually:

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20130415/172067.html

Evan suggested I commit that myself after getting commit access, so I
can just do both once that goes through (planning on adding more test
coverage to both anyway).

Also, I guess we're not renaming the attribute? It's definitely a bit iffy...

Stephen

On Fri, Apr 19, 2013 at 8:14 PM, Bill Wendling <wendling at apple.com> wrote:
> On Apr 19, 2013, at 5:01 PM, Evan Cheng <evan.cheng at apple.com> wrote:
>
>>
>> On Apr 19, 2013, at 4:53 PM, Bill Wendling <wendling at apple.com> wrote:
>>
>>> On Apr 19, 2013, at 7:48 AM, Stephen Lin <swlin at post.harvard.edu> wrote:
>>>
>>>>> OK, I removed some extraneous changes and updated the patch to be
>>>>> based against a mostly non-recursive implementation of sameNoopInput:
>>>>>
>>>>>  http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20130415/172039.html
>>>>>
>>>>> I've also added the restriction that 'returned' can only be on one
>>>>> parameter to allow sameNoopInput to see through 'returned' without
>>>>> recursion or extra bookkeeping. There's a minor tack-on bug fix;
>>>>> apparently the verifier check that 'nest' is only on one parameter was
>>>>> never working correctly...I'm willing to split that off to a separate
>>>>> patch if that's preferable though.
>>>>>
>>>>> The other patch listed is my original e-mail has been committed so is
>>>>> no longer an uncommitted dependency.
>>>>>
>>>>> Stephen
>>>>
>>>> I fixed a small issue (an extraneous recursive call) and rebased against:
>>>>
>>>>   http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20130415/172067.html
>>>>
>>>> (although the patch should merge cleanly against the previous version, too.)
>>>>
>>>
>>> Hi Stephen,
>>>
>>> The IR part of the patch looks okay to me.
>>>
>>> Evan, Are you okay with the CodeGen changes?
>>
>> LGTM
>
> Thanks.
>
> Stephen,
>
> The patch didn't apply cleanly. Someone has updated lib/CodeGen/Analysis.cpp. Could you regen your patch? I'll apply it once you send it. :)
>
> -bw
>