similar to: [LLVMdev] Fail to unroll loop on simple examples.

[I am a newcomer to llvm, so don't believe me.] Hi Claude, I added -debug to the command line in an attempt to study your example, and got out this: Loop Unroll: F[main] Loop %bb1 Loop Size = 4 Can't unroll; loop not terminated by a conditional branch. The source code for that is on line 116 (or so) in lib/Transforms/Utils/LoopUnroll.cpp Based on a quick look at the source code,

Hi, On Fri, Jun 4, 2010 at 5:18 AM, Pekka Nikander <pekka.nikander at nomadiclab.com> wrote: >  Would the best way be to add an option to -loop-unroll, and hack away at lib/Transforms/Utils/LoopUnroll.cpp? Instead, the better alternative is to write another pass similar to LoopUnrollPass.cpp (say LoopPeelPass.cpp) and add new option -loop-peel. The new pass could use llvm::UnrollLoop()

I am trying to implement loop unrolling in a context, where lots of constant propagation has taken place. Unrolling an outer loop might make an inner loop have constant bounds, therefore I want to process the loops outside in, i.e. from parent loops to nested loops. Unfortunately the standard loop pass manager performs loop passes inside out, i.e. from nested loops to parent loops, thereby missing

On Jun 5, 2012, at 3:20 AM, Martin Apel <martin.apel at SIMPACK.de> wrote: > I am trying to implement loop unrolling in a context, where lots of constant propagation has taken place. > Unrolling an outer loop might make an inner loop have constant bounds, therefore I want to process the loops > outside in, i.e. from parent loops to nested loops. > Unfortunately the standard loop

I am working on heavily optimising unusually static C++ code, and have encountered a situation where I basically want an optimiser that would speculatively unroll a loop to see if the first round of the loop could be optimised further. (I happen to know that it is possible.) The previous optimisations that produce the loop in the first place already do a magical job (relying heavily on constant

Hi All, the attached patch performs the splitting in the proposed manner. before applying the patch, please execute svn cp lib/Transforms/Scalar/LoopUnroll.cpp lib/Transforms/Utils/UnrollLoop.cpp to make the patch apply and preserve proper history. Transforms/Utils/UnrollLoop.cpp contains the unrollLoop function, which is now used by the LoopUnroll pass. I've also moved the

Hello Matthijs, On May 9, 2008, at 3:47 AM, Matthijs Kooijman wrote: > Hi All, > > the attached patch performs the splitting in the proposed manner. > before applying the patch, please execute > svn cp lib/Transforms/Scalar/LoopUnroll.cpp lib/Transforms/Utils/ > UnrollLoop.cpp > to make the patch apply and preserve proper history. > > Transforms/Utils/UnrollLoop.cpp

I'm building llvm in MSVS 2008. LoopUnroll.cpp includes UnrollLoop.h line 23: #include "llvm/Transforms/Utils/UnrollLoop.h" but there's no UnrollLoop.h anywhere to be found. My svn tree is synced to TOT. What am I missing?

Hi all, I'm attempting to perform loop unrolling on a single function using the C++ API. Maybe I missed something in the docs, but I cannot figure out a way to do this. The function I'm working with is very simple, containing a single for loop and not much else. I compiled the function to IR using clang with no optimizations enabled. My initial plan was to first run the IndVarSimplify

Hi Dan, > This should still make it easy to write new unrolling passes with > custom heuristics, but it would also be more flexible for passes to > do unrolling in combination with other transformations. Agreed. To shed some light on my specific requirements, I am working with an architecture that has only limited support for loops and control flow. This means that loop unrolling is not

Hello Matthijs, Separating mechanism from policy is a good thing for the LoopUnroll pass. Instead of moving the policy to a subclass though, I think it'd be better to move the mechanism, the unrollLoop function, out to be a standalone utility function, with the LoopInfo object passed in explicitly. FoldBlockIntoPredecessor would also be good to make into a standalone utility function, since

The loop rotation pass does modify the function, which I'm guessing means that a FunctionPassManager can be used to run LoopPasses (this is not obvious to me after looking through the FunctionPassManager code). Unfortunately none of the other passes I'm using (ScalarEvolution, LCSSA, IndVarSimplify, and LoopUnroll) appear to have an effect. I verified that the function can be loop

Vania Joloboff wrote: > Hello, > > We are a research project in joint french-chinese laboratory. We are > considering using > LLVM in our project but we'd like to have some additional info before > we dive in. > Since we are new kids on the block, please bear with us... > > We are interested in using LLVM for emulation of real hardware. What > we have as >

On Aug 6, 2012, at 6:04 AM, Jorge Navas <navas at comp.nus.edu.sg> wrote: > > Hello, > > I wrote my own pass which needs to do some loop unrolling. > > I can perform loop unrolling via opt: > > opt -mem2reg -loops -loop-simplify -loop-rotate -lcssa -loop-unroll > -unroll-count=50 mytest.bc -o mytest.bc > > This command works perfectly. > >

Hi, I'm trying to define a mutable variable, outside functions. The code below is trying to evaluate an expression much like "x = 1" at the module level in Python. It appears that when it tries to JIT the function there is an error because there is no storage allocated for 'x'. How do I do that? thanks, Rob ----- dumped IR ----- ; ModuleID = 'repl-module' %0 =

Hi Dan, > I'm not sure that's very pretty either :-}. My sense is that it's > better to just duplicate those few lines. Then I'll just leave it at that. > An assert at the end that checks that if the loop > wasn't completely unrolled that it's still isLCSSAForm would be a > good addition in any case. Good idea. > I don't think it's desirable

On Fri, Jun 4, 2010 at 8:18 AM, Pekka Nikander <pekka.nikander at nomadiclab.com> wrote: > I am working on heavily optimising unusually static C++ code, and have encountered a situation where I basically want an optimiser that would speculatively unroll a loop to see if the first round of the loop could be optimised further.  (I happen to know that it is possible.)  The previous

>I just sent a reply to Razvan with 3 patches that I think should be merged >into the release branch. I want to keep it somewhat in sync with mainline. >Can you try applying those 3 patches and let me know if it builds for you >and what version of MSVC you have? It doesn't build. first problem is patch 51098 that adds lib\VMCore\Use.cpp and lib\Transforms\Utils\UnrollLoop.cpp

On Wed, Jan 12, 2011 at 6:08 PM, Renato Golin <rengolin at systemcall.org> wrote: > On 12 January 2011 22:28, Rob Nikander <rob.nikander at gmail.com> wrote: >> @x = external global %0* > > Hi Rob, > > Try removing the 'extern', as it implies the variable storage is > elsewhere (ie. another object file). > I have to pass something from the

I am having a strange problem with loop unrolling. Attached is a small example that demonstrates what happens. There is a for-loop with a known trip count, and some control flow inside the loop. If the condition of the control flow only depends on the loop index and loop invariant variables, the loop is not unrolled. However, if the condition involves potentially loop variant variables, the loop