llvm

I recently started working with Clang/LLVM and would like to know if there is any particular documentation on what the -Ox optimization levels do? I couldn't find much on the LLVM documentation page. Can someone share a few links? Thanks. Oak Clang's command-line options documentation is indeed very poor, and in particular you are correct that there's almost no explanation of what the optimizations level do. FreeBSD, however, does add a man page with a useful summary : -O0 -O1 -O2 -Os -Oz -O3 -O4 Specify which optimization level to use. -O0 means "no optimization": this level compiles the

I've looked at the documentation for the LLVM EH intrinsics, and also the Itanium ABI, and I'm stumped on a few things. What is an exception personality function? What jobs does it perform? How would I go about creating one? Maël Nison I had exactly the same question. I've just found these articles which thoroughly explains how it works, the full exception handling process, including the exact purpose of the personality function and a step-by-step implementation. For the sake of having an answer on SO, here is a brief summary of the personality behavior when an exception occurs (but you really

I am learning llvm and wanted to do a proof of concept of an idea I have. Basically, I want to split my compiler and my runtime. The compiler would give a .bc and the runtime would load it via ParseBitcodeFile and use the ExecutionEngine to run it. This part is working. Now, to make system calls easily, I want to be able to implement in my runtime C/C++ functions which do all the system calls (file io, stdout printing, etc). My question is, how could I call these functions from the code from my toy compiler, which is compiled in a different step by llvm, and allow it to be used when executed.

I use Node.js for several jobs on my web apps and so far everthing's ok. But the Node.js uses Google's V8 as the default Javascript engine (JSE) and V8 runs exlusively on the x86 and ARM Instruction Set Architectures (ISA). Now I have a PPC processor Mac computer on which I want to run the Node.js . To do that, I'm adviced to use the Rhino + OpenJDK Shark Virtual Machine + Low Level Virtual Machine ( LLVM ) as the JIT compiler. Currently, that looks like the most applicable way of running Node.js on the PPC ISA. Or, is there a better way to do it? Could you tell beforehand if it would be

3. 常用工具简介 这样llvm就安装完成了。下面是llvm的常用工具简短介绍： clang: C语言编译器，类似于gcc clang++: C++编译器，类似于g++。clang++只是clang的一个别名。 clang-format：按照固定的规范格式化C/C++代码，非常智能。文档请见：http://clang.llvm.org/docs/ClangFormat.html clang-modernize：把按照C++98标准写的代码，转成C++11标准的。文档请见：http://clang.llvm.org/extra/ModernizerUsage.html llvm-as：LLVM 汇编器 llvm-dis： LLVM 反汇编器 opt：LLVM 优化器 llc：LLVM 静态编译器 lli：LLVM的字节码执行器（某些平台下支持JIT） llvm-link：LLVM的字节码链接器 llvm-ar：LLVM的静态库打包器，类似unix的ar。 llvm-nm：类似于unix的nm llvm-ranlib:为 llvm-ar 打包的文件创建索引 llvm-prof：将 ‘llvmprof.out’ raw 数据格式化成人类可读的报告 llvm-ld ：带有可装载的运行时优化支持的通用目标连接器 llvm-config：打印出配置时 LLVM 编译选项、库、等等 llvmc

I am looking into the LLVM system and I have read through the Getting Started documentation . However, some of the nomenclature (and the wording in the clang example) is still a little confusing. The following terms and commands are all part of the compilation process, and I was wondering if someone might be able to explain them a little better for me: clang -S vs. clang -c (I know what -c does, but how do the results differ?) * (Edit) LLVM Bitcode vs. LLVM IR (what is the difference?) .ll files vs. .bc files (what are they, how do they differ?) LLVM assembly code vs. native assembly code (is