search for: canonicalizing

Hello all, I have done some basic experiments about Polly canonicalization passes and I found the SCEV canonicalization has significant impact on both compile-time and execution-time performance. Detailed results for SCEV and default canonicalization can be viewed on: http://188.40.87.11:8000/db_default/v4/nts/32 (or 33, 34) *pNoGen with SCEV canonicalization (run 32): -O3 -Xclang -load

On 09/08/2013 08:03 PM, Star Tan wrote: > Hello all, > > > I have done some basic experiments about Polly canonicalization passes and I found the SCEV canonicalization has significant impact on both compile-time and execution-time performance. Interesting. > Detailed results for SCEV and default canonicalization can be viewed on: http://188.40.87.11:8000/db_default/v4/nts/32 (or

Hello all, I have evaluated the compile-time and execution-time performance of Polly canonicalization passes. Details can be referred to http://188.40.87.11:8000/db_default/v4/nts/recent_activity. There are four runs: pollyBasic (run 45): clang -O3 -Xclang -load -Xclang LLVMPolly.so pollyNoGenSCEV (run 44): clang -O3 -Xclang -load -Xclang LLVMPolly.so -mllvm -polly -mllvm -polly-codegen-scev

At 2013-09-09 05:52:35,"Tobias Grosser" <tobias at grosser.es> wrote: >On 09/08/2013 08:03 PM, Star Tan wrote: >> Hello all, >> >> >> I have done some basic experiments about Polly canonicalization passes and I found the SCEV canonicalization has significant impact on both compile-time and execution-time performance. > >Interesting. > >>

Now, we come to more evaluations on http://188.40.87.11:8000/db_default/v4/nts/recent_activity I mainly care about the compile-time and execution time impact for the following cases: pBasic (run 45): clang -O3 -load LLVMPolly.so pNoGenSCEV (run 44): clang -O3 -load LLVMPolly.so -polly-codegen-scev -polly -polly-optimizer=none -polly-code-generator=none pNoGenSCEV_nocan (run 47): same option

At 2013-09-09 13:07:07,"Tobias Grosser" <tobias at grosser.es> wrote: >On 09/09/2013 05:18 AM, Star Tan wrote: >> >> At 2013-09-09 05:52:35,"Tobias Grosser" <tobias at grosser.es> wrote: >> >>> On 09/08/2013 08:03 PM, Star Tan wrote: >>> Also, I wonder if your runs include the dependence analysis. If this is >>> the

On Fri, Dec 23, 2016 at 3:30 PM Daniel Berlin via llvm-dev < llvm-dev at lists.llvm.org> wrote: > On Fri, Dec 23, 2016 at 2:31 PM, Piotr Padlewski via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > > > > 2016-12-23 22:17 GMT+01:00 David Majnemer <david.majnemer at gmail.com>: > > > > On Fri, Dec 23, 2016 at 1:09 PM, Davide Italiano via llvm-dev

Hi, I observed below behavior with Instruction combiner (visitMul Canonicalization) It tries to convert "(X+C1)*C2" to "X*C2+C1*C2" While transforming if operation is guaranteed to not overflow it does not reflect same property to transformed instructions. Consider following scenarios: 1) If input is ((X+C1)*C2)<nsw> Then post canonicalization output should be

On Fri, Dec 23, 2016 at 2:31 PM, Piotr Padlewski via llvm-dev < llvm-dev at lists.llvm.org> wrote: > > > 2016-12-23 22:17 GMT+01:00 David Majnemer <david.majnemer at gmail.com>: > >> >> >> On Fri, Dec 23, 2016 at 1:09 PM, Davide Italiano via llvm-dev < >> llvm-dev at lists.llvm.org> wrote: >> >>> On Fri, Dec 23, 2016 at 1:01 PM,

I committed a change to fix pr4731 yesterday but after thinking about it some more, I'd like to get other opinions about this. Chris and I talked last week about the need to canonicalize the types used for Neon vector shuffles so that they get CSEd. I guess this was an issue that came up for SSE. For pr4731, I changed llvm-gcc to canonicalize a bitwise vector operation to use i32

2016-12-23 22:17 GMT+01:00 David Majnemer <david.majnemer at gmail.com>: > > > On Fri, Dec 23, 2016 at 1:09 PM, Davide Italiano via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > >> On Fri, Dec 23, 2016 at 1:01 PM, Piotr Padlewski >> <piotr.padlewski at gmail.com> wrote: >> > >> > >> > On Dec 23, 2016 19:47, "Daniel

...ration in something significantly more complicated than it's direct form. Also, can you provide some data? You say "most" and "probably" with no explicit examples. Can you pull out an explicit example of how it would help existing passes, both optimization, and analysis, vs canonicalizing to bitcast? Because i'll be honest, i'm not seeing it. It seems like a more complicated form, for no good reason. It would be like canonicalizing add's to xor's. You can do it, and "most things that reason about adds probably want to reason about xors". However, i thi...

Hi, I encountered some bugs in Reassociate [1] where we are hitting some assertions: assert(!Duplicates.count(Factor) && "Shouldn't have two constant factors, missed a canonicalize"); assert(NumAddedValues > 1 && "Each occurrence should contribute a value”); My understanding is that these assertions enforce that when processing an

...quirements are so we know > which way to canonicalize things. I wonder if this only matters > for DW_TAG_compile_unit? If so, we could canonicalize freely > everywhere else. (For example, we could store a `path:` node > everywhere (dropping the filename/directory distinction, or > canonicalizing it to basename/dirname, etc.), and add a `cwd:` > to the compile unit.) As stated above, I think we are free to canonicalize as we wish. > David also pointed out (in a previous thread about this) that > the frontend (or `DIBuilder`) might be the right location for > canonicalization....

On Aug 17, 2009, at 7:15 AM, Bob Wilson wrote: > I committed a change to fix pr4731 yesterday but after thinking about > it some more, I'd like to get other opinions about this. Chris and I > talked last week about the need to canonicalize the types used for > Neon vector shuffles so that they get CSEd. I guess this was an issue > that came up for SSE. > > For pr4731, I

On Fri, Dec 23, 2016 at 1:09 PM, Davide Italiano via llvm-dev < llvm-dev at lists.llvm.org> wrote: > On Fri, Dec 23, 2016 at 1:01 PM, Piotr Padlewski > <piotr.padlewski at gmail.com> wrote: > > > > > > On Dec 23, 2016 19:47, "Daniel Berlin" <dberlin at dberlin.org> wrote: > > > > Define soon? > > My guess is 1 year or less.

On 09/17/2013 04:12 AM, Star Tan wrote: > Now, we come to more evaluations on http://188.40.87.11:8000/db_default/v4/nts/recent_activity Hi Star Tan, thanks for this very extensive analysis. The results look very interesting. As you found out, just removing some canonicalization passes will reduce compile time, but this reduction may in large part being due to Polly not being able to

So, we've run into some test cases which are pretty alarming. When inlining code in various different paths we can end up with this IR: define void @f(float* %value, i8* %b) { entry: %0 = load float* %value, align 4 %1 = bitcast i8* %b to float* store float %0, float* %1, align 1 ret void } define void @g(float* %value, i8* %b) { entry: %0 = bitcast float* %value to i32* %1 =

On Fri, Dec 23, 2016 at 1:01 PM, Piotr Padlewski <piotr.padlewski at gmail.com> wrote: > > > On Dec 23, 2016 19:47, "Daniel Berlin" <dberlin at dberlin.org> wrote: > > Define soon? > My guess is 1 year or less. > (I've already seen patches to start converting most remaining memdep uses, > like memcpy opt, licm, etc) > > > That's good.

My gut tells me that Hal is right, and we should prefer zexts as long as the select boils down to one instruction, but let me go against my intuition and try to list two reasons why we should prefer selects: * Folding operations into selects: it is trivial to transform f(select X, Const0, Const1) to select X, f(Const0), f(Const1), while doing that can be difficult for zexts. define