similar to: [LLVMdev] Loop-Unroll optimization

1. You should run the passes in the same opt command, for passes like loops which is an analysis pass provides results to the following passes. 2. You can pass a -debug flag to opt to see the some debugging info. 3. I tried this opt -mem2reg -loops -loopsimplify -loop-unroll -unroll-count=3 -debug loop.o -o tt.bc and got this message. Loop Size = 14 Can't unroll; loop not terminated by

Even after all the sequence of commands below bit-code is not showing any effect of loop-unrolling *manish at manish:~/Test2$ llvm-gcc-4.2 -O2 -emit-llvm Hello.c -c -o Hello.bc* *manish at manish:~/Test2$ opt-2.8 -loops Hello.bc -o Hello1.bc* *manish at manish:~/Test2$ opt-2.8 -loopsimplify Hello1.bc -o Hello2.bc* *manish at manish:~/Test2$ opt-2.8 -indvars Hello2.bc -o Hello3.bc* *manish at

Hi, You might want to try running -loops -loop-simplify before loop unroll. >From loop simplify.cpp This pass performs several transformations to transform natural loops into a00011 // simpler form, which makes subsequent analyses and transformations simpler and00012 // more effective. Arushi On Tue, May 3, 2011 at 2:17 PM, Manish Gupta <mgupta.iitr at gmail.com> wrote: > You

Hi, you need to run some optimization passes first. (like -O2) 2011/5/3 Manish Gupta <mgupta.iitr at gmail.com> > I just want to try loop-unroll and see corresponding changes in the bitcode > file. For that any loop will do. Have you been able to test llvm loop-unroll > successfully? > > > On Mon, May 2, 2011 at 10:04 PM, Yuan Pengfei <coolypf at qq.com> wrote: >

You mean like *llvm-gcc-4.2 -O2 -emit-llvm Hello.c -c -o Hello.bc* But still i am not able to observe any effect on bit code by running *opt-2.8 -loop-unroll Hello.bc -o Hello_unroll.bc* On Tue, May 3, 2011 at 3:58 AM, Zakk <zakk0610 at gmail.com> wrote: > Hi, you need to run some optimization passes first. (like -O2) > > 2011/5/3 Manish Gupta <mgupta.iitr at gmail.com>

I just want to try loop-unroll and see corresponding changes in the bitcode file. For that any loop will do. Have you been able to test llvm loop-unroll successfully? On Mon, May 2, 2011 at 10:04 PM, Yuan Pengfei <coolypf at qq.com> wrote: > Hi, > > > The loop that I am trying it on is: > > for(i=0; i< 1000; i++) > > { > > c[i] = a[i] + b[i]; > > }

Is it possible to unroll a loop (forcibly if necessary) with llvm (possibly the -loop-unroll pass) a constant number of times. I believe that I read that the -unroll-count=x option was removed, correct? So is there some other way to do this or is this just not possible in llvm? -------------- next part -------------- An HTML attachment was scrubbed... URL:

Hi, > The loop that I am trying it on is: > for(i=0; i< 1000; i++) > { > c[i] = a[i] + b[i]; > } I can't find any benefit unrolling this loop. ------------------ Yuan Pengfei Peking Unversity, China

Hi all I am trying hello pass in llvm. I have compiled and could generate LLVMHello.so but while giving the pass using opt i am getting below mentioned error. Command used: *opt-2.8 -load ../../cse231_project/llvm/llvm-2.9/Debug/lib/LLVMHello.so -hello < hello.bc* Error opening '../../cse231_project/llvm/llvm-2.9/Debug/lib/LLVMHello.so':

hi, In "LoopUnrollPass.cpp", when trying to reduce unroll count to meet the unroll threshold requirement in line 200 and line 206, variable "CurrentThreshold" is used in the computation, instead of the variable "Threshold", which is defined by: // Determine the current unrolling threshold. While this is normally set // from UnrollThreshold, it is overridden to

On Jan 31, 2012, at 5:16 PM, Ryan Taylor <ryta1203 at gmail.com> wrote: > Is it possible to unroll a loop (forcibly if necessary) with llvm (possibly the -loop-unroll pass) a constant number of times. > > I believe that I read that the -unroll-count=x option was removed, correct? So is there some other way to do this or is this just not possible in llvm? See clang -mllvm

[I am a newcomer to llvm, so don't believe me.] Hi Claude, I added -debug to the command line in an attempt to study your example, and got out this: Loop Unroll: F[main] Loop %bb1 Loop Size = 4 Can't unroll; loop not terminated by a conditional branch. The source code for that is on line 116 (or so) in lib/Transforms/Utils/LoopUnroll.cpp Based on a quick look at the source code,

----- Original Message ----- > From: "Ivan Llopard" <ivanllopard at gmail.com> > To: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu> > Sent: Wednesday, November 21, 2012 10:31:07 AM > Subject: [LLVMdev] Disable loop unroll pass > > Hi, > > We've a target which has hardware support for zero-overhead loops. > Currently, we

Hi all, I have tried to use the loop-unroll pass on a large example, but without success. So I have tried on smaller examples, and I did not get more success. My simplest example is attached. It comes from this C code (using llvm-gcc, but similar result with clang): int main (int argc, char *argv[]) { int i; for (i = 0; i!=5; ++i) {} return 0; } I use this command (version 2.8svn, from

Hi Brendon, Krzysztof, Thanks for your responses. On 21/11/2012 20:49, Brendon Cahoon wrote: > I just wanted to add to Krzysztof's response. I'm not sure if you're > referring to the case when a compile-time trip count loop is completely > unrolled or for a loop with a run-time trip count, which would be partially > unrolled. For Hexagon, if we partially unroll a loop,

Dear LLVM developers, Recently I want to try the pass '-loop-unroll-and-jam' to observe how the IR is transformed, but I don't see the IR changed after doing the following steps. Here are the details for preparing my experiment and I have tried the LLVM 6, 7 and 8: 1) Simple 2D array source code (loop.c) is given ``` #define M 32768 #define N 32768 double a[M][N], b[M][N],

I am the designer for open64 hwloop structure, but I am not a student. Hope the following helps: To transform a loop into hwloop, we need the help from optimizer. For example, while(k3>=10){ sum+=k1; k3 --; } into the form: zdl_loop(k3-9) { sum+=k1; } So, we introduce a new ZDLBR whirl(open64 optimizer intermediate) operator, which represents the loop in whirl as:

Devang, I meant as an end user. -Suresh On Thu, Jun 16, 2011 at 11:00 PM, Devang Patel <dpatel at apple.com> wrote: > Suresh, > > > On Jun 15, 2011, at 9:13 PM, Suresh Purini wrote: > >> Dear all, >> >> What is the default loop-unroll factor in llvm? How can we specify >> our own unroll-factor? > > Here "we" means end user or a

On Mon, Jan 30, 2017 at 4:59 PM Mehdi Amini <mehdi.amini at apple.com> wrote: > > > Another question is about PGO integration: is it already hooked there? > Should we have a more aggressive threshold in a hot function? (Assuming > we’re willing to spend some binary size there but not on the cold path). > > > I would even wire the *unrolling* the other way: just

Dear all, What is the default loop-unroll factor in llvm? How can we specify our own unroll-factor? -Suresh