similar to: [LLVMdev] getSmallConstantTripCount function doesn't work for obvious cases

In my pass, I add LoopInfo as a required pass. Then I'd like to print the constant loop trip count of each loop if it has one. However, every time I call loop-> getSmallConstantTripCount(), it returns 0, even for a very simple loop: for(i=0; i<3; ++i) {;} What's the possible cause of this problem? regards, Bo -------------- next part -------------- An HTML attachment was

Hi, I cannot find the getSmallConstantTripCount function in the current LLVM. Can anyone tell me whether there is still such a function to get the trip count in LLVM? Thank you very much. Best, Han

----- Original Message ----- > From: "Chandler Carruth" <chandlerc at google.com> > To: "Zinovy Nis" <zinovy.nis at gmail.com> > Cc: "Hal Finkel" <hfinkel at anl.gov>, "James Molloy" <james at jamesmolloy.co.uk>, "LLVM Developers Mailing List" > <llvmdev at cs.uiuc.edu> > Sent: Thursday, October 16, 2014

gcc is correct. According to the ISO specification, the for-init-statement is supposed to inject any variable names into the same declarative scope as the condition of an equivalent restructuring of the loop in the form of a while statement, which in turn fronts the declaration to an extra scope that surrounds the /entire/ loop construct. VC++ seems to be scoping the variables as if they were

Hi, I am trying to get a small loop to *not vectorize* for cases where it doesn't make sense. For instance, this loop: void foo(int a[4][8], int n) { int b[4][8]; for(int i = 0; i < 4; i++) { for(int j = 0; j < n; j++) { a[i][j] = b[i][j]; } } } * Has maximum of 8ints copy. LLVM tries to use Memcpy for the inner loop. It is not helpful to perform

Hi Deepali, SCEV reports the backedge taken count as "((-1 * (sext i32 (3 + %x) to i64))<nsw> + ((sext i32 (3 + %x) to i64) smax (sext i32 (6 + %x) to i64)))", so symbolically it does have an answer. Ideally SCEV should be able to exploit <nsw> on (3 + %x) and (6 + %x) to fold the expression above to "3", but due to some systemic issues SCEV can't exploit

Hello I'm wandring to know how many times a block is executed inside a loop ? knowing that I can't use getSmallConstantTripCount() because the number is unkown "for (i=0;i<N;i++) for example" I'm using a Function pass for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) { if (Loop *L = LI->getLoopFor(BB)) { if (L->getHeader() ==

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, 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

Hi Sriram, Thanks for performing this analysis. The problem here, both for memcpy and the vectorizer, is that we can’t predict the size of “n”, even though the only use of ’n’ is for the loop bound for the alloca [4 x [8 x i32]]. If you change the unroll condition to TC >= 0 then you will disable loop unrolling for all loops because getSmallConstantTripCount returns an unsigned number. You

I found out that Loop::getTripCount method is obsolete in LLVM 3.1 Is there an alternative? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20120702/ea6ca4e6/attachment.html>

Hello, I want to insert a control-block before every outermost loop. My current solution is: 1) find each outermost loop in some function; 2) find the loop header with Loop->getHeader() APIs, and then insert the controller block before the header block of current loop. But I encounters problems when there multi subsequent loops in the following example, where there is no code between loops:

Hi Nadav, Thanks for the response. I forgot to mention that there is an upper limit of 16 for the Trip Count check, TinyTripCountVectorThreshold = 16; if (TC > 0u && TC < TinyTripCountVectorThreshold). So right now, any loop with Trip Count as 0, or with value >=16, LV with unroll. With the change to the lower bound, it will also include the loop with 0 trip count. SCEV returns 0

Jay Freeman (saurik) wrote: > gcc is correct. According to the ISO specification, the for-init-statement > is supposed to inject any variable names into the same declarative scope as > the condition of an equivalent restructuring of the loop in the form of a > while statement, which in turn fronts the declaration to an extra scope that > surrounds the /entire/ loop construct.

On Mar 11, 2013, at 4:23 PM, Daniel Berlin <dberlin at dberlin.org> wrote: > On Mon, Mar 11, 2013 at 3:45 PM, Manman Ren <mren at apple.com> wrote: >> >> On Mar 11, 2013, at 2:37 PM, Daniel Berlin <dberlin at dberlin.org> wrote: >> >>> On Mon, Mar 11, 2013 at 2:06 PM, Manman Ren <mren at apple.com> wrote: >>>> >>>>

On Mar 11, 2013, at 7:52 PM, Daniel Berlin wrote: > On Mon, Mar 11, 2013 at 4:56 PM, Manman Ren <mren at apple.com> wrote: >> >> On Mar 11, 2013, at 4:23 PM, Daniel Berlin <dberlin at dberlin.org> wrote: >> >>> On Mon, Mar 11, 2013 at 3:45 PM, Manman Ren <mren at apple.com> wrote: >>>> >>>> On Mar 11, 2013, at 2:37 PM,

Leroy Tennison writes: > I am going to take a really wild guess and say "Try replacing the outermost quotes with single quotes or escape the double quotes around the numeral 1". Your second example has double quotes within double quotes and I'm wondering if that's getting rendered as "yum --debuglevel=" 1 " install ..." (extra space added for

On Mon, Mar 11, 2013 at 4:56 PM, Manman Ren <mren at apple.com> wrote: > > On Mar 11, 2013, at 4:23 PM, Daniel Berlin <dberlin at dberlin.org> wrote: > >> On Mon, Mar 11, 2013 at 3:45 PM, Manman Ren <mren at apple.com> wrote: >>> >>> On Mar 11, 2013, at 2:37 PM, Daniel Berlin <dberlin at dberlin.org> wrote: >>> >>>> On

On Mar 12, 2013, at 12:20 PM, Daniel Berlin <dberlin at dberlin.org> wrote: > On Tue, Mar 12, 2013 at 10:10 AM, Manman Ren <mren at apple.com> wrote: >> >> On Mar 11, 2013, at 7:52 PM, Daniel Berlin wrote: >> >>> On Mon, Mar 11, 2013 at 4:56 PM, Manman Ren <mren at apple.com> wrote: >>>> >>>> On Mar 11, 2013, at 4:23 PM,

Hello, After discussions with Daniel, Dan and others, here is an updated proposal for struct-access-path aware TBAA. Given an example struct A { int x; int y; }; struct B { A a; int z; }; struct C { B b1; B b2; int *p; }; struct D { C c; }; The purpose of struct-path-aware TBAA is to say "C::b1.a" will alias with "B::a.x", "C::b1.a" will alias with