similar to: [LLVMdev] How to avoid loopverify failures after replacing the backedge with an edge(latchBB to exitBB) in a looppass?

On May 7, 2013, at 8:26 PM, zhiyuan yang <sjtu.yzy at gmail.com> wrote: > Hi, > > I am writing a loop pass to replace the backedge with an edge from latch to exit. > Now I just replace the terminator of latch with another BranchInst, and the loop will not be a loop after my pass. However, it turns out a failure of loopverify after executing my pass: > > opt:

Sorry for forgetting to reply all... It works! Thank you very much! But I also wonder how do you know this function will work while there are no documents noticing that. I try learning LLVM by reading its code, but soon feel lost in so many functions. Just like I have many tools, but don't know which to use and what difference it could make. Is there some better ways to learn LLVM? On Wed,

Hello everyone, Sorry to bother you. I'm an undergraduate, and I'm trying to finish my graduation project using LLVM. In this project, I hope to transform all loop in program to condition statement. For example, Before transformation: for (int i = 0; i < 5; i++) a++; After transformation: int i = 0; if (i < 5) a++; i++; The idea is very clear, however, I'm a newbie to LLVM.

Hi, I was reading some loop related code and I don’t quite understand an assertion in LoopBase<BlockT, LoopT>::getLoopPredecessor(). /// getLoopPredecessor - If the given loop's header has exactly one unique /// predecessor outside the loop, return it. Otherwise return null. /// This is less strict that the loop "preheader" concept, which requires /// the predecessor to have

Hi Xin, Thank you for your reply! I have tried the 3 alias analyses you have mentioned on LLVM 3.5: 1) $ opt -globalsmodref-aa -aa-eval < xxx.bc > /dev/null (May-alias response 100%) 2) $ opt -tbaa -aa-eval < xxx.bc > /dev/null (May-alias response 100%) 3) $ opt -cfl-aa -aa-eval < xxx.bc> /dev/null (Unknown command line argument '-cfl-aa') It seems that they are not

Dear all, I was wondering if there are some reliable alias analyses build on top of LLVM other than basicaa. Thank you! Zhiyuan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150407/db07dba3/attachment.html>

Hi, I am learning R by reading R source code. Here is one question I have about the optim function in R. The context : In the optim.R, after all the prep steps, the main function call call is made via : .External2(C_optim, par, fn1, gr1, method, con, lower, upper). So, it seems to me, to follow what is going on from here, that I should read the optim function in \src\library\stats\src\optim.c

Hello, I use R a lot, one thing bugs me is that when I try the following > x<- -8 > x^(1/3) [1] NaN However, it is fine with -8^(1/3). Priority goes to the power. Can you help me out for this? Thanks. Best, Zhiyuan J. ZHENG Ph.D. Candidate Economic Department Virginia Polytechnic Institute and State University Phone: 540-231-5120 , Blacksburg, VA, 24060

Dear all, I am trying to reproduce the "Percent May Alias" result described in PLDI 07's paper "Making Context-Sensitive Points-to Analysis with Heap Cloning Practical For The Real World" (http://llvm.org/pubs/2007-06-10-PLDI-DSA.html ). However, my "Percent May Alias" for all the benchmarks is much greater, especially "bzip2". The DSA code I use is

Dear John, I intend to implement the improvements on DSA. After running DSA on SPEC, I found DSA gives low precision for mcf and bzip2. I have checked the most imprecise c files in mcf an found that the code seems to be a mixture of "PHI" and "GEP" instructions. Could you please give me some hints about what the big picture of the improvement should be and how to start? Thank

Duncan, here is part of the assembly around the problem area. I used gcc -S -flto to generate the .s file, llvm-as on the .s fiile will show error: invalid cast opcode for cast from 'i40' to 'float' %638 = trunc i40 %637 to float %633 = bitcast i8* %632 to float* %634 = bitcast float* %633 to i40* %635 = load i40* %634, align 1 %636 = shl i40 %635, 7 %637 = ashr i40

Hi ZY, On 11/05/13 22:21, Zhiyuan Ren wrote: > Duncan, > > here is part of the assembly around the problem area. I used gcc -S -flto to > generate the .s file, llvm-as on the .s fiile will show error: invalid cast > opcode for cast from 'i40' to 'float' %638 = trunc i40 %637 to float > > %633 = bitcast i8* %632 to float* > %634 = bitcast float* %633 to

Duncan, Thanks for getting back to me. I am not sure how to find the original bitcode (and related Ada source code) that causes the truncate. This is the error message that gcc gave me when I tried to compile an Ada source file using dragonegg plugin (gcc -c -fplugin...). ZY ps, sorry for multiple emails, trying to find out how to reply to a thread in the mailing list On Sat, May 11, 2013 at

Duncan, Is there a way (switch) for embedding original source code in the generated .s file? thanks, ZY On Sun, May 12, 2013 at 4:12 AM, Duncan Sands <baldrick at free.fr> wrote: > Hi ZY, > > > On 11/05/13 22:21, Zhiyuan Ren wrote: > >> Duncan, >> >> here is part of the assembly around the problem area. I used gcc -S -flto >> to >> generate

Hi ZY, On 11/05/13 20:37, Zhiyuan Ren wrote: > Duncan, > > Thanks for getting back to me. I am not sure how to find the original bitcode > (and related Ada source code) that causes the truncate. This is the error > message that gcc gave me when I tried to compile an Ada source file using > dragonegg plugin (gcc -c -fplugin...). use -S instead of -c and add -flto The resulting

Hello, I am new to LLVM and doing some experiment with 3.2 on Ada code. Can anyone help me on the following error message? Thanks, ZY LLVM ERROR: Cannot select: 0xa7a0bf0: f32 = truncate 0xa7a5ea8 [ID=24] 0xa7a5ea8: i32 = X86ISD::SHLD 0xa790280, 0xa790390, 0xa76e088 [ID=22] 0xa790280: i32,ch = load 0xa7386a0, 0xa7a68d8, 0xa7a5628<LD1[%1482+4], anyext from i8> [ID=19]

Hello, I have a question about exit blocks : is it true that every loop's exit block will contain only those comparisons that will lead to exit or to continue execution in loop? I have tried many examples , after optimizations it seems to be true, but does it have to be so? -------------- next part -------------- An HTML attachment was scrubbed... URL:

On 12/05/13 18:01, Zhiyuan Ren wrote: > Duncan, > > Is there a way (switch) for embedding original source code in the generated .s file? No. Ciao, Duncan.

Duncan, Is there a way to link or trace .s code to certain lines in the original source code? Thanks, ZY On Sun, May 12, 2013 at 12:01 PM, Duncan Sands <baldrick at free.fr> wrote: > On 12/05/13 18:01, Zhiyuan Ren wrote: > >> Duncan, >> >> Is there a way (switch) for embedding original source code in the >> generated .s file? >> > > No. >

Hi ZY, On 10/05/13 22:34, Zhiyuan Ren wrote: > Hello, I am new to LLVM and doing some experiment with 3.2 on Ada code. Can > anyone help me on the following error message? a truncate from an i32 to an f32 is not valid. This caused the code generator to abort. What is the original bitcode that caused this? Ciao, Duncan. > > Thanks, > ZY > > > LLVM ERROR: Cannot select: