similar to: [LLVMdev] AMD Developer position

This is slightly of main LLVM topic but I think many might be interested. We are currently recruiting for full time roles for a high-level programming model R&D position. The role is defined as follows: Job Description: The Fusion System Software team is looking for an experienced researcher and software developer to develop high-level programming models for our new Fusion hardware

Hi, AMD is currently looking for talented compiler engineers to work with LLVM and this list seemed like a good place to let people know. Below is the job description, please send me an email if you are interested. Regards, Ben Compiler engineer ATI is now part of the new AMD. AMD and ATI have joined forces, combining AMD¹s technology leadership in microprocessors with ATI¹s strengths in

AMD Research Co-op position: LLVM compiler developer As part of a larger research project within AMD we are looking for a co-op to work on a compiler project that is using LLVM as its backend. The project is studying how explicitly parallel vector programming models (such as Cuda, OpenCL, and ISPC) can be compiled without loss of performance portability. The interested candidate should have

On Wed, Jul 12, 2017 at 11:58 AM, Peter Lawrence <peterl95124 at sbcglobal.net> wrote: > > On Jun 30, 2017, at 12:00 PM, via llvm-dev <llvm-dev at lists.llvm.org> > wrote: > > Date: Fri, 30 Jun 2017 09:16:54 -0700 > From: Peter Lawrence via llvm-dev <llvm-dev at lists.llvm.org> > To: Hal Finkel <hfinkel at anl.gov> > Cc: llvm-dev <llvm-dev at

Dave, I will try to locate and take a look at the actual llvm logic that deletes based on UB-presence, one of these days, and report back. In the mean time... Your “For example:" is a plausibility argument only. It is not meaningful until you can show this happening in real source code from real applications that are compiler warning free and static analysis warning free. Hal

Dave, The way I see it there should be just one pass that implements deleting UB (maybe it would come to be called UBCE), and that one pass should have a command line option simply for the reason than all passes should have one. Peter Lawrence. > On Jul 26, 2017, at 10:02 PM, David Blaikie <dblaikie at gmail.com> wrote: > > > > On Wed, Jul 26, 2017 at 9:23 PM

Dave, Dead code elimination is generally done in a pass called dead code elimination, Can you give concrete examples why the same would not be true for UB code elimination ? Yes, speculatively hoisting code requires it to be UB-free, but that has nothing to do with UBCE deleting entire blocks of code because of the existence of UB. The former requires an analysis proving UB-absense, the

Sean, Let me re-phrase a couple words to make it perfectly clear > On Jul 21, 2017, at 6:29 PM, Peter Lawrence <peterl95124 at sbcglobal.net> wrote: > > Sean, > > Dan Gohman’s “transform” changes a loop induction variable, but does not change the CFG, > > Hal’s “transform” deletes blocks out of the CFG, fundamentally altering it. > > These are two totally

> On Jul 21, 2017, at 10:55 PM, Mehdi AMINI <joker.eph at gmail.com> wrote: > > > > 2017-07-21 22:44 GMT-07:00 Peter Lawrence <peterl95124 at sbcglobal.net <mailto:peterl95124 at sbcglobal.net>>: > Mehdi, > Hal’s transformation only kicks in in the *presence* of UB > > No, sorry I entirely disagree with this assertion: I believe we

David, -fsanitize=undefined sounds great, but is not quite what I want. I recently ran into a problem with "CodeGen/MachineSink.cpp” [*], for a target that has to expand Select into control flow. The original IR had two select in a row that were based on the same condition, so the CMP that sets the FLAGS reg in the second select was MCSE’ed to the earlier CMP in the first

Mehdi, Hal’s transformation only kicks in in the *presence* of UB, and it does not matter how that UB got there, whether by function inlining or without function inlining. The problem with Hal’s argument is that the compiler does not have a built in ouija board with which it can conjure up the spirit of the author of the source code and find out if the UB was intentional with the

> > > Message: 5 > Date: Tue, 25 Jul 2017 00:12:35 -0700 > From: Sean Silva via llvm-dev <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> > To: Peter Lawrence <peterl95124 at sbcglobal.net <mailto:peterl95124 at sbcglobal.net>> > Cc: llvm-dev <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>>, John Regehr >

On Mon, Jul 31, 2017 at 7:40 AM Peter Lawrence <peterl95124 at sbcglobal.net> wrote: > Dave, > Dead code elimination is generally done in a pass called dead > code elimination, > Can you give concrete examples why the same would not be true for UB code > elimination ? > I haven't actually looked at how optimizations on the basis of the code being UB-free

On 06/28/2017 02:18 PM, Chandler Carruth wrote: > On Wed, Jun 28, 2017 at 12:09 PM Peter Lawrence > <peterl95124 at sbcglobal.net <mailto:peterl95124 at sbcglobal.net>> wrote: > > Chandler, > Please give some citations, I’ve search the > llvm-dev archives and didn't find any. > > > They are all in the discussions from Nuno,

Chandler, Please give some citations, I’ve search the llvm-dev archives and didn't find any. Peter Lawrence. > On Jun 28, 2017, at 12:01 PM, Chandler Carruth <chandlerc at gmail.com> wrote: > > On Wed, Jun 28, 2017 at 9:39 AM Peter Lawrence <peterl95124 at sbcglobal.net <mailto:peterl95124 at sbcglobal.net>> wrote: > > Preface: This paper

Hal, Mehdi points out I mis-quoted you, I apologize sincerely. Mehdi, Thank you for forcing me to go back and re-read what Hal wrote, I could have sworn Hal and I were in agreement at the time I wrote you, Must have been asleep at the wheel, not enough sleep last night However my request for a more concrete example stands Here’s what I said > This doesn’t make sense to me, a

Andrew, your response highlights a naming problem in LLVM, which is that "array" and "vector" mean the same thing in normal computer language and compiler theory usage, so it is inconvenient and misleading within LLVM to give one a very specific meaning that is different from the other.... to the LLVM developers I would suggest using the term

> > Having read all of these threads, I am thoroughly convinced by the positions put forward by others. > Chandler, others have decided to let the compiler continue mis-compiling the function-inlining example, others have decided to not fix the inability to hoist a loop invariant divide out of a loop. It sounds like you haven’t even thought about these things let alone

Sean, Dan Gohman’s “transform” changes a loop induction variable, but does not change the CFG, Hal’s “transform” deletes blocks out of the CFG, fundamentally altering it. These are two totally different transforms. And even the analysis is different, The first is based on an *assumption* of non-UB (actually there is no analysis to perform) the second Is based on a *proof* of existence of UB

Chandler, Al right then, stay on topic, what do you actually think should be done about the fact that the current proposal will mis-compile the function-inlining example, and won’t be able to hoist a loop-invariat divide out of a loop. Peter Lawrence. > On Jun 28, 2017, at 11:03 PM, Chandler Carruth <chandlerc at gmail.com> wrote: > > On Wed, Jun 28, 2017 at