similar to: [LLVMdev] Whole program optimization

On 26.01.2011, at 04:39, John McCall wrote: > On Jan 24, 2011, at 10:36 AM, Hendrix_ at gmx.net wrote: >> I was using "clang -O3 -S -emit-llvm" got some very optimized output. >> >> Then I did "clang -S -emit-llvm" (without optimization) and wanted to optimized the code in a >> separate pass. The llvm program "opt" did not do anything.

On Jan 27, 2011, at 12:02 PM, Hendrix_ at gmx.net wrote: > OK, I am looking for "LTO"/global optimization. So the function definition will remain "somewhere else" (externally), and the optimizer will find in some other module to possibly inline it later on. > > I am planning to concat all the *.ll (eg "link" the files) and pass them to the

On 27.01.2011, at 21:12, Devang Patel wrote: > > On Jan 27, 2011, at 12:02 PM, Hendrix_ at gmx.net wrote: > >> OK, I am looking for "LTO"/global optimization. So the function definition will remain "somewhere else" (externally), and the optimizer will find in some other module to possibly inline it later on. >> >> I am planning to concat all the

On 27.01.2011, at 21:12, Devang Patel wrote: > > On Jan 27, 2011, at 12:02 PM, Hendrix_ at gmx.net wrote: > >> OK, I am looking for "LTO"/global optimization. So the function definition will remain "somewhere else" (externally), and the optimizer will find in some other module to possibly inline it later on. >> >> I am planning to concat all the

On Jan 27, 2011, at 12:37 PM, Hendrix_ at gmx.net wrote: > > On 27.01.2011, at 21:12, Devang Patel wrote: > >> >> On Jan 27, 2011, at 12:02 PM, Hendrix_ at gmx.net wrote: >> >>> OK, I am looking for "LTO"/global optimization. So the function definition will remain "somewhere else" (externally), and the optimizer will find in some other

> > > Is there a reason why LLVM's link-time optimization won't work for you? > > http://llvm.org/docs/GoldPlugin.html > http://llvm.org/docs/LinkTimeOptimization.html > > Well the primary motivation to move to LLVM is licensing which is why we also ditched binutils since we can't package gcc for iOS due to the GPL. So in the end the gold plugin wouldn't

Hi All, After the initial learning curve, we're excited to have put together a completely gcc/binutils-free toolchain based on LLVM. Now that we have things working, we desperately need to optimize the resulting binaries. Our bin files are up to 10x their fully optimized gcc equivalent (1.5k vs 16k). This is for a bare metal ARM based system so this is significant. We're using lld for

Thanks Nick. I've been pursuing Gao's technique but can't seem to get opt to remove obviously dead code from even the following trivial example: int mult(int a, int b){ return a*b; } int main(void){ return 0; } While mult is never called it still is not removed. I just can't seem to get opt to understand it's seeing the whole program so it can remove this

Hi All, I have installed LinkTimeOptimization.html document in doc directory to describe LTO interface. - Devang

Hi all, we're working on compile-time instrumentation for ThreadSanitizer (a data race detector, see http://code.google.com/p/data-race-test and http://code.google.com/p/data-race-test/wiki/CompileTimeInstrumentation), which is implemented as an opt plugin that is ran for each client C/C++ module we compile. To build a binary consisting of several modules the following steps are performed:

Devang, Wonderful! Thanks for explaining this, it really helps. I took the liberty of fixing a few grammatical errors and some HTML usage/style things. No significant change to the content was made. Reid. On Mon, 2006-08-14 at 11:23 -0700, Devang Patel wrote: > Hi All, > > I have installed LinkTimeOptimization.html document in doc directory > to describe LTO interface. >

On Apr 18, 2011, at 6:46 AM, Alexander Potapenko wrote: > Hi all, > > we're working on compile-time instrumentation for ThreadSanitizer (a > data race detector, see http://code.google.com/p/data-race-test and > http://code.google.com/p/data-race-test/wiki/CompileTimeInstrumentation), > which is implemented as an opt plugin that is ran for each client > C/C++ module we

Hi, Op 13-aug-03, om 19:35 heeft Chris Lattner het volgende geschreven: > On Mon, 14 Aug 2006, Devang Patel wrote: >> I have installed LinkTimeOptimization.html document in doc >> directory to describe LTO interface. > > Here's a link: :) > http://llvm.org/docs/LinkTimeOptimization.html Does the LTO-interface function already, or is functionality currently

On Mon, 14 Aug 2006, Devang Patel wrote: > I have installed LinkTimeOptimization.html document in doc directory to > describe LTO interface. Here's a link: :) http://llvm.org/docs/LinkTimeOptimization.html -Chris -- http://nondot.org/sabre/ http://llvm.org/

On May 26, 2009, at 10:52 AM, Rafael Espindola wrote: > Today support for plugins has been committed to BFD. That is the file > format abstraction library used by binutils. This now works Very nice Rafael! Can you please update the web page to mention this, e.g. in the LinkTimeOptimization.html document and wherever else relevant? -Chris > > $ llvm-gcc -emit-llvm -O2 -c a.c

Hi, all I use llvm-gcc -O4 to compile SPEC 2000, some benchmarks can't be built successfully, such as 164.gzip, 175.vpr etc. The error messages are as follows. .. zh.o unlzw.o unpack.o unzip.o util.o zip.o -o gzip bits.o: file not recognized: File format not recognized collect2: ld returned 1 exit status specmake: *** [gzip] Error 1 specmake options 2> options.err |

Hi All, How to write a link time optimization pass in llvm with LTO? Is there a document, just like http://llvm.org/docs/WritingAnLLVMPass.html tells us how to write a llvm pass? Thanks,

Hi All, I am migrating a build system of an existing project from 'Object files' based executable generation to 'LLVM Bitcode' files based exe generation and applying OPT pass to LLVM Bitcode. I found out the following 4 step procedure. Please let me know if this is the right procedure or is there any other easy way of doing it. I need to modify 'Makefile' accordingly. I

Hi, I need advice in instrumenting programs using liblto and gold plugin. Specifically, I added my pass in tools/lto/LTOCodeGenerator.cpp. My pass inserts functions (myLoad and myStore) for some load and store instructions. The functions exist in a library file. I found that the approach works for the example in the link: http://llvm.org/docs/GoldPlugin.html $ llvm-gcc -flto a.c -c -o a.o $ ar q

Hi Duncan, > 4.gcc -g -O2 -o .libs/mergedexe .libs/mergedbc.s -pthread > -Wl,--export-dynamic .libs/lib1.a -lssl -lcrypto -ldl -pthread .libs/lib2.so >if you pass -O4 rather than -O2 to clang I think it will in essence do this all >for you already. It might even do the link time optimization for you at -O2 >even, I'm not sure. No, if I use clang for producing