similar to: [LLVMdev] Vectorization: Next Steps

On Feb 2, 2012, at 7:56 PM, Hal Finkel wrote: > As some of you may know, I committed my basic-block autovectorization > pass a few days ago. I encourage anyone interested to try it out (pass > -vectorize to opt or -mllvm -vectorize to clang) and provide feedback. > Especially in combination with -unroll-allow-partial, I have observed > some significant benchmark speedups, but, I

Carl-Philip, The reason that this does not vectorize is that it cannot vectorize the stores; this leaves only the mul-add chains (and some chains with loads), and they only have a depth of 2 (the threshold is 6). If you give clang -mllvm -bb-vectorize-req-chain-depth=2 then it will vectorize. The reason the heuristic has such a large default value is to prevent cases where it costs more to

Hi Hal, > As some of you may know, I committed my basic-block autovectorization > pass a few days ago. I encourage anyone interested to try it out (pass > -vectorize to opt or -mllvm -vectorize to clang) and provide feedback. > Especially in combination with -unroll-allow-partial, I have observed > some significant benchmark speedups, but, I have also observed some > significant

I have a super-simple test case 4x4 matrix * 4-vector which gets correctly unrolled, but is not vectorized by -bb-vectorize. (I used llvm 3.1svn) I attached the test case so you can see what is going wrong there. 2012/2/3 Hal Finkel <hfinkel at anl.gov> > As some of you may know, I committed my basic-block autovectorization > pass a few days ago. I encourage anyone interested to try

If you run with -vectorize instead of -bb-vectorize it will schedule the cleanup passes for you. -Hal Sent from my Verizon Wireless Droid -----Original message----- From: "Carl-Philip Hänsch" <cphaensch at googlemail.com> To: Hal Finkel <hfinkel at anl.gov> Cc: llvmdev at cs.uiuc.edu Sent: Tue, Feb 14, 2012 16:10:28 GMT+00:00 Subject: Re: [LLVMdev] Vectorization: Next

On Tue, 2011-11-08 at 12:12 +0100, Tobias Grosser wrote: > On 11/08/2011 11:45 AM, Hal Finkel wrote: > > I've attached the latest version of my autovectorization patch. > > > > Working through the test suite has proved to be a productive > > experience ;) -- And almost all of the bugs that it revealed have now > > been fixed. There are still two programs that

On 11/08/2011 03:36 PM, Hal Finkel wrote: > On Tue, 2011-11-08 at 12:12 +0100, Tobias Grosser wrote: >> On 11/08/2011 11:45 AM, Hal Finkel wrote: >>> I've attached the latest version of my autovectorization patch. >>> >>> Working through the test suite has proved to be a productive >>> experience ;) -- And almost all of the bugs that it revealed

I will test your suggestion, but I designed the test case to load the memory directly into <4 x float> registers. So there is absolutely no permutation and other swizzle or move operations. Maybe the heuristic should not only count the depth but also the surrounding load/store operations. Are the load/store operations vectorized, too? (I designed the test case to completely fit the SSE

On Mon, 2012-02-06 at 14:26 -0800, Chris Lattner wrote: > On Feb 2, 2012, at 7:56 PM, Hal Finkel wrote: > > As some of you may know, I committed my basic-block autovectorization > > pass a few days ago. I encourage anyone interested to try it out (pass > > -vectorize to opt or -mllvm -vectorize to clang) and provide feedback. > > Especially in combination with

That works. Thank you. Will -vectorize become default later? 2012/2/14 Hal Finkel <hfinkel at anl.gov> > If you run with -vectorize instead of -bb-vectorize it will schedule the > cleanup passes for you. > > -Hal > > *Sent from my Verizon Wireless Droid* > > > -----Original message----- > > *From: *"Carl-Philip Hänsch" <cphaensch at

On Mon, 2012-02-13 at 11:11 +0100, Carl-Philip Hänsch wrote: > I will test your suggestion, but I designed the test case to load the > memory directly into <4 x float> registers. So there is absolutely no > permutation and other swizzle or move operations. Maybe the heuristic > should not only count the depth but also the surrounding load/store > operations. I've attached

I've attached the latest version of my autovectorization patch. Working through the test suite has proved to be a productive experience ;) -- And almost all of the bugs that it revealed have now been fixed. There are still two programs that don't compile with vectorization turned on, and I'm working on those now, but in case anyone feels like playing with vectorization, this patch

On 11/08/2011 11:45 AM, Hal Finkel wrote: > I've attached the latest version of my autovectorization patch. > > Working through the test suite has proved to be a productive > experience ;) -- And almost all of the bugs that it revealed have now > been fixed. There are still two programs that don't compile with > vectorization turned on, and I'm working on those now,

Duncan, I also noticed cases where vector IR is scalariezd by the codegen. From what I have seen (which is based on a different vectorizer with a different code model, etc) there are two main areas for improvements: 1. Complex instructions - Instructions such as shuffles are very sensitive to the ability of the codegen to lower them. If a vectorizer generates shuffle instructions which are not

On Fri, Feb 03, 2012 at 09:49:30AM +0100, Duncan Sands wrote: > Hi Hal, > > > As some of you may know, I committed my basic-block autovectorization > > pass a few days ago. I encourage anyone interested to try it out (pass > > -vectorize to opt or -mllvm -vectorize to clang) and provide feedback. > > Especially in combination with -unroll-allow-partial, I have

On Feb 7, 2012, at 12:10 PM, Hal Finkel wrote: >>> 1. "Target Data" for vectorization - I think that in order to improve >>> the vectorization quality, the vectorizer will need more information >>> about the target. This information could be provided in the form of a >>> kind of extended target data. This extended target data might contain:

On Tue, 2011-11-08 at 20:24 +0100, Tobias Grosser wrote: > On 11/08/2011 03:36 PM, Hal Finkel wrote: > > On Tue, 2011-11-08 at 12:12 +0100, Tobias Grosser wrote: > >> On 11/08/2011 11:45 AM, Hal Finkel wrote: > >>> I've attached the latest version of my autovectorization patch. > >>> > >>> Working through the test suite has proved to be a

On Sat, 2011-10-29 at 14:02 -0500, Hal Finkel wrote: > On Sat, 2011-10-29 at 12:30 -0500, Hal Finkel wrote: > > Ralf, et al., > > > > Attached is the latest version of my autovectorization patch. llvmdev > > has been CC'd (as had been suggested to me); this e-mail contains > > additional benchmark results. > > > > First, these are preliminary

On Tue, 2011-11-08 at 20:24 +0100, Tobias Grosser wrote: > On 11/08/2011 03:36 PM, Hal Finkel wrote: > > On Tue, 2011-11-08 at 12:12 +0100, Tobias Grosser wrote: > >> On 11/08/2011 11:45 AM, Hal Finkel wrote: > >>> I've attached the latest version of my autovectorization patch. > >>> > >>> Working through the test suite has proved to be a

I am starting to use the sample profiler to analyze new performance opportunities. The loop unroller has popped up in several of the benchmarks I'm running. In particular, libquantum. There is a ~12% opportunity when the runtime unroller is triggered. This helps functions like quantum_sigma_x (http://sourcecodebrowser.com/libquantum/0.2.4/gates_8c_source.html#l00149). The function accounts