similar to: [LLVMdev] array assignemnt

Dear All, As of late I am having a hard time getting my head around how array accesses are translated by Clang into LLVM IR: the often misunderstood GEP instruction. I am trying to reverse-engineer array accesses to discover the number of dimensions and actual indexes of the original, and I am beginning to wonder whether this is possible at all. To illustrate (some of) my troubles, consider

Hi Gabriel, I suggest you don't bother with testcases like this that are doing undefined things. For example, neither i nor k are initialized, so the result of accessing the array is undefined. Thus the frontend can (and apparently does) produce anything strange thing it does. What is more, the result aux is unused, so there is no obligation to compute it correctly. I think you will get

----- Original Message ----- > From: "Duncan Sands" <duncan.sands at gmail.com> > To: "Hal Finkel" <hfinkel at anl.gov> > Cc: llvmdev at cs.uiuc.edu > Sent: Friday, October 5, 2012 12:10:03 PM > Subject: Re: TSVC/Equivalencing-dbl > > Oops, I ran the testsuite wrong: read clang output for dragonegg > output. Okay, can you resummarize? Do

----- Original Message ----- > From: "Duncan Sands" <duncan.sands at gmail.com> > To: "Hal Finkel" <hfinkel at anl.gov> > Cc: llvmdev at cs.uiuc.edu > Sent: Friday, October 5, 2012 2:50:06 PM > Subject: Re: TSVC/Equivalencing-dbl > > Hi Hal, > > On 05/10/12 20:32, Hal Finkel wrote: > > ----- Original Message ----- > >>

On 15/11/12 10:15, Philip Ashmore wrote: > On 15/11/12 08:58, Duncan Sands wrote: >>> Is there a way to get the target triple of the machine the code is running on, >>> or barring that, the machine llvm was built on? >> >> clang -v >> >> Ciao, Duncan. >> _______________________________________________ >> LLVM Developers mailing list >>

Thanks for the answer, So if i understand right, i can't directly compile the c code using clang. And i need to manually generate some llvm ir to replace the builtin function. Is that right? 2012/6/4 Duncan Sands <baldrick at free.fr> > Hi Christophe, > > > I recently migrate from llvm/clang 2.8 to 3.1. > > The builtin __builtin_ia32_pcmpeqd128 compile and works

Hi Duncan, On 11/10/12 15:47, Duncan Sands wrote: > Hi Roel, > >> When going through the internals of the old C back-end, I see that the CBE >> encapsulates arrays into a struct. The source code has the following comment to >> explain this behaviour. >> >> // Arrays are wrapped in structs to allow them to have normal >> // value semantics

Hi Christophe, > So if i understand right, i can't directly compile the c code using clang. > And i need to manually generate some llvm ir to replace the builtin function. > > Is that right? I think so, though I don't know much about clang's support for such intrinsics, just what's in http://clang.llvm.org/compatibility.html#vector_builtins Ciao, Duncan. > >

Hi Hal, To get my understanding right, is this a test-case problem or there is a problem with x86 code generation?. I can spend some time to look into the problem. Thanks, Shivaram -----Original Message----- From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On Behalf Of Hal Finkel Sent: Saturday, October 06, 2012 1:57 AM To: Duncan Sands Cc: llvmdev at cs.uiuc.edu

PS: Here's how I can reproduce with clang on linux: clang -S -o tsc.ll -O0 -flto -std=gnu99 tsc.c ; clang -S -o dummy.ll -O0 -flto -std=gnu99 dummy.c ; opt -std-compile-opts tsc.ll -S -o tsc.1.ll ; opt -std-compile-opts dummy.ll -S -o dummy.1.ll ; llvm-link tsc.1.ll dummy.1.ll -S -o total.ll ; opt -std-link-opts total.ll -S -o total.1.ll ; llc total.1.ll ; gcc -o z total.1.s The program

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

On 15/11/12 10:10, Duncan Sands wrote: > On 15/11/12 10:15, Philip Ashmore wrote: >> On 15/11/12 08:58, Duncan Sands wrote: >>>> Is there a way to get the target triple of the machine the code is >>>> running on, >>>> or barring that, the machine llvm was built on? >>> >>> clang -v >>> >>> Ciao, Duncan. >>>

Hi, I am generating llvm IR code for C source code using clang as the front end. I am wondering if there is any way of mapping an llvm IR line number back to its C source code line number. Thanks Sincerely Arvind -- Arvind Sudarsanam Utah State University Phone: (435) 512-7769 E-mail: theonemorpheus at gmail.com Web-site: http://cc.usu.edu/~asudarsanam

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, We are developing a bounded model checker for C/C++ programs (http://baldur.iti.kit.edu/llbmc/) that operates on LLVM's intermediate representation. While checking a C++ program that uses STL containers we noticed that llvm-gcc and clang handle pointer differences in disagreeing ways. Consider the following C function: int f(int *p, int *q) { return q - p; } Here's the

> llvm-gcc doesn't support address spaces. This is a clang-only feature. However it could be implemented in llvm-gcc. Ciao, Duncan.

> I see the same with clang. I'm not sure why the optimizers do so much better > when they can see that sp is a local array (the special initial values don't > matter). It is the scalar replacement of aggregates pass that puts everything into registers when sp is a local array. What happens is: the tail recursion in wf is eliminated. wf is inlined into g. scalarrepl turns the

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, > 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 6 November 2012 14:52, Duncan Sands <baldrick at free.fr> wrote: > Hi Anitha, > > > On 06/11/12 10:19, Anitha Boyapati wrote: > >> Hi Duncan >> I am facing a build error about __builtin_iceil >> > > it's surely just that dragonegg doesn't have any support for this builtin. > ok. Just verified that Target.cpp and x86_builtins do not have