similar to: [LLVMdev] how to let memory dependency analysis use globalsmodref

Hello, I am trying to simplify the CFG of a given code and eliminate the conditionals, even though I will obtain codes that are not semantically equivalent. For example, given a simple loop: for(i=0; i<N; i++){    a[i] = i;     if (i%2==0)       a[i] += 12; } I would keep only the loop, without the if statement: for(i=0; i<N; i++){    a[i] = i; } I can eliminate such conditionals on

Thanks to you both. On my Linux (centos6) system, I have reproduce a variant of the bug and learned about -plugin-opt=-debug-pass=Arguments which I infer from comments is intended to built arguments to “opt” however I found that some of the arguments don’t seem to be quite correct. I assume this just minor bit rot. bin/opt -o pass1.bc -datalayout -notti -basictti -x86tti -targetlibinfo

0 down vote favorite <http://stackoverflow.com/questions/34049511/how-to-pass-optimization-passes-to-clang#> I'm trying to debug an issue for a new target where a testcase fails with -O1 optimization and passes with -O0 optimization. I got a list of optimization passes being performed when 'clang -O1' is called like this: llvm-as < /dev/null | opt -O1 -disable-output

Does LLVM have loop multiversioning ? it seems it does not with clang++ -O3 -mllvm -debug-pass=Arguments program.c -c bash-4.1$ clang++ -O3 -mllvm -debug-pass=Arguments fast_algorithms.c -c clang-3.6: warning: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated Pass Arguments: -datalayout -notti -basictti -x86tti -targetlibinfo -no-aa -tbaa -scoped-noalias

Hi, List, As you may know, BCC of android makes use of LLVM's major components. Its LTO actually selects some optimizations of LLVM. I found it can not only use "-functionattrs". I must first use -argpromotion first, or I end up this error: Pass 'Deduce function attributes' is not initialized. Verify if there is a pass dependency cycle. Required Passes: bcc:

Hi, > If I compile the program using the following command line i.e. > > $ clang -O3 -lm *.c this may be doing link time optimization. > > then > > $ time ./a.out > > real 0m2.606s > user 0m2.584s > sys 0m0.012s > > BUT, if I use all the optimizations enabled with -O3 but specify them > explicity i.e. you can just use "opt -O3"

Hi all, I would like to know which optimization passes are performed at -O2 by opt. So I used following command: llvm-as < /dev/null | opt -O2 -std-compile-opts -disable-output -debug-pass=Arguments I've got following output for LLVM opt 2.9: Pass Arguments: -no-aa -tbaa -basicaa -simplifycfg -domtree -scalarrepl -early-cse Pass Arguments: -targetlibinfo -no-aa -tbaa -basicaa

Hello I need some help here please. If we compile source files directly in to native code: $ clang -O3 -lm *.c then the runtime is like following real 0m2.807s user 0m2.784s sys 0m0.012s and If we emit LLVM bytcode and apply optimizations $ clang -O3 -c -emit-llvm *.c $ llvm-link *.o -o comb.ll $ time lli ./comb.ll then the runtime is real 0m2.671s user 0m2.640s sys 0m0.020s But, if I

Hi, > I tried it with -o - but its producing an error > > gcc: fatal error: cannot specify -o with -c, -S or -E with multiple files > > What you suggest? what I wrote: >> for F in *.c ; do B=`basename $F .c` ; gcc -fplugin=/path/to/dragonegg.so >> -S -o - $F -fplugin-arg-dragonegg-emit-ir | opt -adce -o $B.ll ; done >> clang *.ll Thanks to the for loop and

On Jan 3, 2015, at 11:52 PM, Bill Wendling <isanbard at gmail.com> wrote: > On Jan 2, 2015, at 8:32 PM, David Callahan <dcallahan at fb.com> wrote: > >> Hi, >> >> I am new to the LLVM dev community so forgive a perhaps obvious question. I am looking at bug 17623 which is an LTO/optimizer interaction bug. I am working on a Mac with Xcode installed but have

add -basicaa to your command line :) On Mon, May 11, 2015 at 7:15 AM, Willy WOLFF <willy.mh.wolff at gmail.com> wrote: > I play a bit more with MemoryDependenceAnalysis by wrapping my pass, and > call explicitely BasicAliasAnalysis. Its still using No Alias Analysis. > > How can I let MemoryDependenceAnalysis use BasicAliasAnalysis? > > Please, find attached my pass. >

Hi Yes, they both are exactly the same. Regards Shahzad On Tue, Jun 12, 2012 at 9:38 AM, Duncan Sands <baldrick at free.fr> wrote: > Hi, is the comb.ll used here: > > >> $ time lli ./comb.ll >> >> then the runtime is >> >> real    0m2.671s >> user    0m2.640s >> sys     0m0.020s >> >> But, if I convert this same file comb,ll

Hello Duncan Sorry for the mistake. Actually that error occurred when I was compiling all the files at once, NOT in for loop. The for loop is working perfectly as it is dealing with individual files. I have now one new issue. Let me specify it briefly. If I compile the program using the following command line i.e. $ clang -O3 -lm *.c then $ time ./a.out real 0m2.606s user 0m2.584s sys

Does anyone have experience to compile Linux kernel in LLVM-2.6? I am working on a C/C++ race detection framework and want to test in large applications. But I do have a lot of errors while compiling Linux kernel 2.6.3 using LLVM-2.6. Actually, I only need to get the .bc bitcode file. Anyboy does similar work before? Which Linux kernel version is used and any skills? Thanks. Lei /****** * Lei

Thanks Duncan It was really helpful. Regards Abdul On Fri, Jun 8, 2012 at 7:23 PM, Duncan Sands <baldrick at free.fr> wrote: > Hi, > > >> If I compile the program using the following command line i.e. >> >> $ clang -O3 -lm *.c > > > this may be doing link time optimization. > > >> >> then >> >> $ time ./a.out >>

Hi all, I'm implementing an intra-procedural analysis. For correctness, during the analysis of each function I need to know which global variables may be modified by other functions in order to avoid wrong assumptions about those variables. I looked at lib/Analysis/IPA/GlobalsModRef.cpp and it seems that it does what I want. My problem is that I don't know how to use it ;-( I wrote a

Hi Jorge, > I'm implementing an intra-procedural analysis. For correctness, during > the analysis of each function I need to know which global variables > may be modified by other functions in order to avoid wrong assumptions > about those variables. > > I looked at lib/Analysis/IPA/GlobalsModRef.cpp and it seems that it > does what I want. My problem is that I don't

Hi, I try to use MemoryDependenceAnalysis in a pass to analyse a simple function: void fct (int *restrict*restrict M, int *restrict*restrict L) { S1: M[1][1] = 1; S2: L[2][2] = 2; } When I iterate over MemoryDependenceAnalysis on the S2 statement, I get the load instruction for the first depth of the array, that’s ok. But I get also the load and store for the S1 statement. I assume the

Hi, is the comb.ll used here: > $ time lli ./comb.ll > > then the runtime is > > real 0m2.671s > user 0m2.640s > sys 0m0.020s > > But, if I convert this same file comb,ll in to native binary the same as the comb.ll used here: > $ clang comb.ll ? Ciao, Duncan. > > and execute it, then the runtime increases alot > > $ time ./a.out > > real

Hello I am trying to enable globalsmodref-aa by default. globalmodref-aa is a ModulePass and therefore can be invalidated and need to be rerun. I see globalsmodref-aa is enabled in LTO passmanager by adding the analysis pass explicitly. I wonder whether globalsmodref-aa can be enabled/run based on pass dependencies, i.e. those indicated in getAnalysisUsage(). Thanks, Xin -------------- next