search for: longlivepoison

...t of LLVM is the way > forwards, it would probably be worth taking the time to consider all > possible options for improvement. I just realized there isn't much information about this proposal. The best I could find is slides 23-24 of this: http://llvm.org/devmtg/2016-11/Slides/Lopes-LongLivePoison.pdf The basic idea is that instead of accessing 2 shorts as i32, you could access them as <2 x i16>. In case of structures with different element types, you would need to use structures, which LLVM also supports. For the proposal to be correct, you can slice a value into smaller vector...

On 20 March 2018 at 09:39, Nuno Lopes via llvm-dev <llvm-dev at lists.llvm.org> wrote: > Hi, > > Let me give you my view of the status: > The proposal you mentioned was, I believe, well understood and accepted. > Except for one bit, which was that it requires correct typing of load/store > operations. That is, if you load an i32, it means you are loading a single >

Daniel, Thanks for taking the time to respond. Regarding GVN and newGVN, I recently finished a search through the llvm-dev archives for “nsw” in the subject line, and GVN was discussed in some of those threads [1]. In particular it was claimed that there was a right choice for GVN to make given two ADD instructions, one with the “nsw” attribute and one without, the one without ‘nsw’

...wards, it would probably be worth taking the time to consider all >> possible options for improvement. >> > > I just realized there isn't much information about this proposal. The best > I could find is slides 23-24 of this: http://llvm.org/devmtg/2016-11 > /Slides/Lopes-LongLivePoison.pdf > > The basic idea is that instead of accessing 2 shorts as i32, you could > access them as <2 x i16>. In case of structures with different element > types, you would need to use structures, which LLVM also supports. For the > proposal to be correct, you can slice a value i...

Hi, Thanks everybody that showed up in our talk at the LLVM dev meeting and to those that provided feedback so far. The slides are already online: http://llvm.org/devmtg/2016-11/Slides/Lopes-LongLivePoison.pdf The main question that some people raised was whether we could have bitwise poison instead of value-wise poison, since that semantics seems to be more natural as values continue to be just a bag of bits. During the talk I didn't have a good answer to this question. We've now studied t...