[LLVMdev] GetElementPtr

[Ryan Taylor]

Or is it in the docs such that when you use the word "independent", you
really mean "independent of a particular target" and not actually "target
independent"?

On Thu, Dec 8, 2011 at 11:18 AM, Ryan Taylor <ryta1203 at gmail.com> wrote:

>
>
> ---------- Forwarded message ----------
> From: Ryan Taylor <ryta1203 at gmail.com>
> Date: Thu, Dec 8, 2011 at 11:13 AM
> Subject: Re: [LLVMdev] GetElementPtr
> To: Reid Kleckner <reid.kleckner at gmail.com>
>
>
> There is no support for gep, it's my understanding that it's
> target-independent, so there's no reason to put the lowering in the target
> lowering portion is there?
>
> Eventually the GEP has to be lowered correctly, to the target
> architecture, but the docs state that it's target-independent, so given
> that it should be possible to lower it without knowing any specifics about
> the target, correct?
>
>
> On Thu, Dec 8, 2011 at 11:08 AM, Reid Kleckner <reid.kleckner at gmail.com>wrote:
>
>> Why would you want to remove all GEP instructions?
>>  inttoptr+math+ptrtoint don't have the exact same semantics in LLVM IR.
>>  GEP instructions have certain guarantees about what addresses can be
>> computed with them that straight pointer arithmetic doesn't.
>>
>> Reid
>>
>>
>> On Thu, Dec 8, 2011 at 2:00 PM, Ryan Taylor <ryta1203 at gmail.com> wrote:
>>
>>> Do you think I could use the SelectionDAGBuilder in a pass to accomplish
>>> this for me? if there is already code that does this I don't really think I
>>> should have to do this again, unless it's not possible to access that code
>>> from the stage where I want to use it?
>>>
>>> On Thu, Dec 8, 2011 at 12:56 AM, Pedro Ferreira <
>>> pedro.ferreira at imgtec.com> wrote:
>>>
>>>>  I was unaware of its removal. I am still using 2.8. I grep'd the
>>>> source tree for that pass and found it on the header I mentioned; it led me
>>>> to believe the pass was still there.
>>>>
>>>> The transformation itself isn't complicated; doing it manually should
>>>> be simple.
>>>>
>>>>
>>>> On 07/12/11 21:50, Ryan Taylor wrote:
>>>>
>>>> There is a GEPSplitterPass in the Scalar.h but not in the
>>>> LLVM_SRC/lib/Transforms/Scalar folder, there is no GEPSplitterPass.cpp
>>>> file. Is it possible to get this from 2.8 and compile it and use it for 2.9?
>>>>
>>>>  On Wed, Dec 7, 2011 at 12:31 PM, Ryan Taylor <ryta1203 at gmail.com>wrote:
>>>>
>>>>> Looking at the release notes for 2.9, it appears that GEPSplitterPass
>>>>> has been removed from 2.9. Is this the case, can I access it anyways or no?
>>>>>
>>>>> Due to all the changes between versions of LLVM, it's not timely to
>>>>> switch to any other version of LLVM, since the code modifications would be
>>>>> too many. Any other ideas?
>>>>>
>>>>>
>>>>> On Wed, Dec 7, 2011 at 12:14 PM, Ryan Taylor <ryta1203 at gmail.com>wrote:
>>>>>
>>>>>> Yes, exactly along these lines, how do I use this pass? It's not
>>>>>> documented in the Transforms section of llvm.org
>>>>>>
>>>>>>
>>>>>>  On Wed, Dec 7, 2011 at 6:06 AM, Pedro Ferreira <
>>>>>> pedro.ferreira at imgtec.com> wrote:
>>>>>>
>>>>>>>  You mean, something along the lines of the GEPSplitterPass?
>>>>>>>
>>>>>>> // GEPSplitter - Split complex GEPs into simple ones
>>>>>>>
>>>>>>> in
>>>>>>>
>>>>>>> ./include/llvm/Transforms/Scalar.h
>>>>>>>
>>>>>>>
>>>>>>> On 06/12/11 20:53, Ryan Taylor wrote:
>>>>>>>
>>>>>>>  Does a transform exist to breakdown the GEP?
>>>>>>>
>>>>>>>
>>>>>>>  _______________________________________________
>>>>>>> LLVM Developers mailing listLLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.eduhttp://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>
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>>
>
>
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