search for: linktimeoptimization

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

On Aug 24, 2007, at 1:45 PM, Holger Schurig wrote: > In the gray block below "Example of link time optimization" there are > some source files and then a list of commands to execute: > > $ llvm-gcc4 --emit-llvm -c a.c -o a.o > $ llvm-gcc4 -c main.c -o main.o > $ llvm-gcc4 a.o main.o -o main > > 1) in current LLVM (e.g. llvm itself, cfe, llvm-gcc-4.0) no binary

> In the gray block below "Example of link time optimization" there are > some source files and then a list of commands to execute: > > $ llvm-gcc4 --emit-llvm -c a.c -o a.o > $ llvm-gcc4 -c main.c -o main.o > $ llvm-gcc4 a.o main.o -o main > > 1) in current LLVM (e.g. llvm itself, cfe, llvm-gcc-4.0) no binary with > the name "llvm-gcc4" get's

> The documentation could be updated to say llvm-gcc > but unless you specify the prefix "llvm-" during configure, it wont be > named that either :) llvm-top did this for you, see the "--program-prefix=llvm-" in http://llvm.org/svn/llvm-project/llvm-gcc-4.0/trunk/build-for-llvm-top.sh (I know that llvm-top hasn't even been announced, but at least when Reid

> Well, it depends on the configure parameter used while building llvm- > gcc. Hmm, there are other pages on the the website that tell you how you should configure gcc, e.g. you're led from "How to build the C/C++ Frontend" at http://llvm.org/docs/CFEBuildInstrs.html to Subversion HEAD (by virtue of an "svn co"). Then you're supposed to look at README.LLVM. And

On Aug 24, 2007, at 1:45 PM, Holger Schurig wrote: > $ llvm-gcc --emit-llvm -c a.c -o a.o > $ llvm-gcc -c main.c -o main.o > $ llvm-gcc a.o main.o -o main > a.o: file not recognized: File format not recognized > collect2: ld returned 1 exit status > > Okay, that did not really work :-/ This document describes interface between llvm and linker. You need system linker that

> > $ llvm-gcc --emit-llvm -c a.c -o a.o > > $ llvm-gcc -c main.c -o main.o > > $ llvm-gcc a.o main.o -o main > > a.o: file not recognized: File format not recognized > > collect2: ld returned 1 exit status > > > > Okay, that did not really work :-/ > > This document describes interface between llvm and linker. You need > system linker that

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/

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 limited (this is what I understood from the 1.8 release notes)? In the...

...ass them to the "global" optimizer, as "size" is a very important optimization criterium to me. After that, the back-end will be invoked. > Is that a good approach? How about just add -O4 on clang (or llvm-gcc) command line to get LTO optimizations ? See http://llvm.org/docs/LinkTimeOptimization.html http://llvm.org/docs/GoldPlugin.html On Mac OS X, it is a checkbox in Xcode. - Devang

Hi, Is there a tutorial on how to get started with writing link-time optimization passes? The documentation at http://www.llvm.org/docs/LinkTimeOptimization.html explains the design of the LTO interface, but does not explain where to start writing code. Would my pass go inside libLTO.a or is it separate from libLTO.a? What I would like to be able to do is traverse through the entire call graph of the program, which is only available at link-tim...

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.

..., 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. > > - > Devang > _______________________________________________ > LLVM Developers mailing list > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev

The web page "LLVM Link Time Optimization: Design and Implementation" contains errors. In the gray block below "Example of link time optimization" there are some source files and then a list of commands to execute: $ llvm-gcc4 --emit-llvm -c a.c -o a.o $ llvm-gcc4 -c main.c -o main.o $ llvm-gcc4 a.o main.o -o main 1) in current LLVM (e.g. llvm itself, cfe, llvm-gcc-4.0) no

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 > $ llvm-gcc -emit-llvm -O2 -c b.c > $ ar --plugin libLLVMgold.so q a.a a.o > $ llvm-gcc -use-gold-plugin b.o a.a -o t > $ objdump -d t | grep main\>: -A 2 > 0000000000400330 <main...

...and then run gdb on llvm-ld with -O5 and two .bc files, trying to catch LTO in action. I've also scanned the compiled tools, and none of them appear to use the symbol 'createLLVMOptimizer' (or anything with 'lto', etc). The document at http://llvm.org/releases/2.1/docs/LinkTimeOptimization.html doesn't seem to be of much help for getting started with this. How do I provoke LTO? Any suggestions? Thanks, Jeff Jeff Inman -- jti at lanl.gov Advanced Architectures for Computation Los Alamos National Laboratory

> > > 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 work for licensing reasons even if we can get it to work technically but thanks for the lin...

I have gold from cvs, and llvm-gcc/llvm from svn. My platform is Ubuntu 9.04 x86_64. I've configured llvm-gcc with "--enable-multilib". When compiling the LTO example from http://llvm.org/docs/LinkTimeOptimization.html I have no problems with 64-bit compilation, but get the following with -m32. luked at node:~/tests/lto$ make USE32=1 llvm-gcc -m32 -c -o main.o main.c llvm-gcc -m32 --emit-llvm -c -o a.o a.c ar q a.a a.o ar: creating a.a llvm-gcc -m32 -use-gold-plugin main.o a.a -o main /home/luked/loc...

Hi all! I played around with the LLVM LTO example(https://llvm.org/docs/LinkTimeOptimization.html#example-of-link-time-optimization), but got some questions. As the document says, the function foo4 should be removed. However, under my test, function foo4 is not removed. I have tried both gnu ld with LLVMgold.so and lld, neither of them removes function foo4. I compile and run the example...

...ot;global" optimizer, as "size" is a very important optimization criterium to me. After that, the back-end will be invoked. >> Is that a good approach? > > How about just add -O4 on clang (or llvm-gcc) command line to get LTO optimizations ? > See http://llvm.org/docs/LinkTimeOptimization.html > http://llvm.org/docs/GoldPlugin.html > On Mac OS X, it is a checkbox in Xcode. > - > Devang My backend doesnt supply lto :( I am trying to emulate lto like this: clang *.c -S -emit-llvm cat *.ll > very_big.ll opt -O3 -extra-things... llc very_big.ll.optimized ('Ease o...