similar to: [LLVMdev] dynamic data dependence extraction using llvm

Dear Dibyendu, Thanks for your response. :-) > If you are looking for only dependences which are inter-iteration (dependence distance != 0 ) you can do a post-pass on the ld/st addresses collected Yes, I am more interested in inter-iteration dependence. Could you provide more information or some links on post-pass approach? I have no idea on your method. :-) > eliminate such

Dear Dibyendu and Mobi, Thanks for your help! :-) I finally figure it out. The solution is really simple. I just need to generate a new bitcode file with the following command: ----- opt -mem2reg -indvars test1.bc -o test2.bc ----- Then the load/store for induction variables will be removed and replaced by PHI instructions and all remaining load/store instructions are those I am interested in. I

Hello, I'd like to listen your opinions regarding my research with LLVM. My work is a dynamic analysis of data dependences [1]. Briefly speaking, I'm instrumenting memory loads/stores and loop entries/exits/back edges, and then calculating data dependences in runtime, especially focusing on loop-carried dependences. So far, I have been working with a binary-level instrumentation tool

R-help - I have this set of aggregated tables (sample data below via dput()). And I would like to have delayValue as the column variables with the "temp" (temp1, temp2, temp3) values as the row variables. However I would like to have the temp variables *aggregated into single rows* so that I have the frequency ("Freq" | counts) of each time each "delayValue" occurs

Hi all, I have a C code in Linux, it has 7 pointers and compile e run OK, but when I run in R happens problems with calloc function, it returns NULL. ############################################### > int *temp1,*temp2,*temp3,*temp4; temp1 = (int *)calloc(col,sizeof(int)); if(temp1 == NULL){ printf("\n\n No Memory1!"); exit(1); } temp2 = (int *)calloc(col,sizeof(int));

Hi mobi, Sorry, I am new to clang AST and can not get the point you mentioned. :-( What I try to do is develop a tool that can analyze data dependence at runtime. Therefore, I need to analyze trace containing memory accessing information (eg. arrays within loops). To do that, I first instrument a recording function to get addresses of load/store instructions. However, there are

Hi, Here is a preliminary (monolithic) version you can comment on. This is still buggy, however, and I'll be testing for and fixing bugs over the next few days. I've used your version of the strong siv test. Thanks! -- Sanjoy Das. http://playingwithpointers.com -------------- next part -------------- A non-text attachment was scrubbed... Name: patch.diff Type: application/octet-stream

I changed the input C to using a 64 bit type for the loop index (this eliminates 'sext' instructions in the IR) Here the IR produced with clang -O0 define float @foo(i64 %start, i64 %end, float* %A) #0 { entry: %start.addr = alloca i64, align 8 %end.addr = alloca i64, align 8 %A.addr = alloca float*, align 8 %sum = alloca [4 x float], align 16 %i = alloca i64, align 8

This is a rather interesting, but I don't think it is a bug - it is just things that "you are not supposed to do"... you are assuming a certain evaluation order of the 4 "$" operators in " D$ABC[D$M] = D$V[D$M] " as in: temp1 <- D$M # 2nd and 4th temp2 <- D$V[temp1] # 3rd D$ABC[temp1] = temp2 # 1st What R did was this:

Hi, I have read an email from the mail list. And I have a question about loop rotation. What is it if it is the case below. -------------------------------------------------------------------------- loop: A br X B br Y C br loop, Z ------------------------------------------------- Thanks! Jerry [LLVMdev] Loop rotation and loop inversion in LLVM? Andrew Trickatrick at apple.com Mon May 20

Hello all, I am trying to understand how to specify nested factors when using coxph(), and if it is appropriate to nest these factors in my situation. In the simplest form, I am testing two different temperatures, with each temperature being performed twice in different experimental periods (e.g. Temp5 performed in Period A and C, Temp4 performed in Period B and D) I am trying to see if survival

Hello, First the version info: platform powerpc-apple-darwin8.6.0 arch powerpc os darwin8.6.0 system powerpc, darwin8.6.0 status major 2 minor 3.1 year 2006 month 06 day 01 svn rev 38247 language R version.string Version 2.3.1 (2006-06-01) I have encountered some unusual behavior when trying to

On 7 November 2013 17:18, Frank Winter <fwinter at jlab.org> wrote: > LV: We don't allow storing to uniform addresses > This is triggering because it didn't recognize as a reduction variable during the canVectorizeInstrs() but did recognize that sum[q] is loop invariant in canVectorizeMemory(). I'm guessing the nested loop was unrolled because of the low trip-count, and

I am trying my luck on this global reduction kernel: float foo( int start , int end , float * A ) { float sum[4] = {0.,0.,0.,0.}; for (int i = start ; i < end ; ++i ) { for (int q = 0 ; q < 4 ; ++q ) sum[q] += A[i*4+q]; } return sum[0]+sum[1]+sum[2]+sum[3]; } LV: Checking a loop in "foo" LV: Found a loop: for.cond1 LV: Found an induction variable. LV: We

I have been looking into this small test case (Part A) where loop vectorization is disabled due to possible store-load forwarding conflict (Part B). As you can see, due to the presence of dependence distance 2 the loop is vectorizable only for a width of 2. However, the presence of dependence distance 15 (due to y[j-15]) results in store-load forwarding issue as store packet of y[16:17] (iteration

Hi R experts, I'm attempting to run Linear Discriminant Analysis using the lda function in the MASS package. I've got around 50 predictor variables and one response variable. My response variable has 5 numeric categories that represent different clusters of fish abundance data (clusters were developed using Bray-Curtis and NMDS), and my predictor variables are environmental variables that

Hi Ashutosh, Have you been following the recent Loop Access Analysis work? LAA was split out from the Loop Vectorizer that have been performing the kind of loop versioning that you describe. The main reason was to be able to share this functionality with other passes. Loop Access Analysis is an analysis pass that computes basic memory dependence and the runtime checks. The versioning decision

Hi, I would like to know if it is possible to extract the source level names of variables that create loop-carried dependencies. For example, for the following code: for (int i = 0; i < A_ROW; i++) { for (int j = 1; j < B_COL; j++) { a_matrix[i][j] = a_matrix[i][j - 1]; } } I get the following AST: #pragma omp parallel for

On Mar 18, 2008, at 9:21 AM, Wojciech Matyjewicz wrote: > Hi, > >> Cool! I think the most critical part of this is to get a good >> interface for dependence analysis. There are lots of interesting >> implementations that have various time/space tradeoffs. >> >> For example, it would be great if Omega was available as an option, >> even if the compiler

> Sorry for coming to the discussion so late. I have a couple of questions/comments: Actually, you're note is timely, because I'm planning to send out a patch (as soon as I update LangRef and rerun tests) that supports safelen but *not* lexical dependences. I don't need the safelen for Julia, but having done the work and seeing that OpenMP needs it, feel that I should finish the