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diff --git a/docs/GettingStarted.html b/docs/GettingStarted.html index 8dadc17f20..f4083f3481 100644 --- a/docs/GettingStarted.html +++ b/docs/GettingStarted.html @@ -1,477 +1,468 @@ <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> - <head> - <title>Getting Started with LLVM System</title> - </head> - - <body bgcolor=white> - <center><h1>Getting Started with the LLVM System<br><font size=3>By: <a - href="mailto:gshi1@uiuc.edu">Guochun Shi</a>, - <a href="mailto:sabre@nondot.org">Chris Lattner</a> and - <a href="http://www.cs.uiuc.edu/~vadve">Vikram Adve</a> - </font></h1></center> - - <!--=====================================================================--> - <h2><a name="Contents">Contents</a></h2> - <!--=====================================================================--> - - <ul> - <li><a href="#overview">Overview</a> - <li><a href="#starting">Getting started with LLVM</a> - <ol> - <li><a href="#quickstart">Getting started quickly (a summary)</a> - <li><a href="#checkout">Checkout LLVM from CVS</a> - <li><a href="#terminology">Terminology and Notation</tt></a> - <li><a href="#objfiles">The location for object files</tt></a> - <li><a href="#config">Local Configuration Options</tt></a> - <li><a href="#environment">Setting up your environment</a> - <li><a href="#compile">Compiling the source code</a> - </ol> - <li><a href="#layout">Program layout</a> - <ol> - <li><a href="#cvsdir">CVS directories</a> - <li><a href="#dd"><tt>Depend</tt>, <tt>Debug</tt>, & - <tt>Release</tt> directories</a></li> - <li><a href="#include"><tt>llvm/include</tt></a> - <li><a href="#lib"><tt>llvm/lib</tt></a> - <li><a href="#test"><tt>llvm/test</tt></a> - <li><a href="#tools"><tt>llvm/tools</tt></a> - </ol> - <li><a href="#tutorial">An example using the LLVM tool chain</a> - <li><a href="#links">Links</a> - </ul> - - - <!--=====================================================================--> - <center> - <h2><a name="overview"><b>Overview</b></a></h2> - </center> - <!--=====================================================================--> - - <p>The <a href"starting">next section</a> of this guide is meant to get - you up and running with LLVM, and to give you some basic information about - the LLVM environment. The <a href"#quickstart">first subsection</a> gives - a short summary for those who are already familiar with the system and - want to get started as quickly as possible. - - <p>The later sections of this guide describe the <a - href"#layout">general layout</a> of the the LLVM source-tree, a <a - href="#tutorial">simple example</a> using the LLVM tool chain, and <a - href="#links">links</a> to find more information about LLVM or to get - help via e-mail. - - <!--=====================================================================--> - <center> - <h2><a name="starting"><b>Getting Started</b></a></h2> - </center> - <!--=====================================================================--> - - - <!--=====================================================================--> - <h3><a name="quickstart"><b>Getting Started Quickly (A Summary)</b></a></h3> - <!--=====================================================================--> - - Here's the short story for getting up and running quickly with LLVM: +<head> + <title>Getting Started with LLVM System</title> +</head> + <body bgcolor="white"> + +<center> +<h1>Getting Started with the LLVM System<br> +<font size="3">By: <a href="mailto:gshi1@uiuc.edu">Guochun Shi</a>, <a + href="mailto:sabre@nondot.org">Chris Lattner</a> and <a + href="http://www.cs.uiuc.edu/%7Evadve">Vikram Adve</a> </font></h1> +</center> + <!--=====================================================================--> + +<h2><a name="Contents">Contents</a></h2> + <!--=====================================================================--> + +<ul> + <li><a href="#overview">Overview</a> </li> + <li><a href="#starting">Getting started with LLVM</a> <ol> - <li>Find the path to the CVS repository containing LLVM (we'll call this <i>CVSROOTDIR</i>). - <li><tt>cd <i>where-you-want-llvm-to-live</i></tt> - <li><tt>cvs -d <i>CVSROOTDIR</i> checkout llvm</tt> - <li><tt>cd llvm</tt> - <li>Edit <tt>Makefile.config</tt> to set local paths. This includes - setting the install location of the C frontend, and the various paths - to the C and C++ compilers used to build LLVM itself. - <li>Set your LLVM_LIB_SEARCH_PATH environment variable. - <li><tt>gmake -k |& tee gnumake.out - # this is csh or tcsh syntax</tt> + <li><a href="#quickstart">Getting started quickly (a summary)</a> + </li> + <li><a href="#checkout">Checkout LLVM from CVS</a> </li> + <li><a href="#terminology">Terminology and Notation</a> </li> + <li><a href="#objfiles">The location for object files</a> </li> + <li><a href="#config">Local Configuration Options</a> </li> + <li><a href="#environment">Setting up your environment</a> + </li> + <li><a href="#compile">Compiling the source code</a> </li> </ol> - - <p>See <a href="#environment">Setting up your environment</a> on tips to - simplify working with the LLVM front-end and compiled tools. See the - other sub-sections below for other useful details in working with LLVM, - or go straight to <a href="#layout">Program Layout</a> to learn about the - layout of the source code tree. - - <!-------------------------------------------------------------------------> - <h3><a name="terminology">Terminology and Notation</a></h3> - <!-------------------------------------------------------------------------> - - <p>Through this manual, the following names are used to denote paths - specific to the local system and working environment. <i>These are not - environment variables you need to set, but just strings used in the rest - of this document below.</i>. In any of the examples below, simply replace - each of these names with the appropriate pathname on your local system. + </li> + <li><a href="#layout">Program layout</a> + <ol> + <li><a href="#cvsdir">CVS directories</a> </li> + <li><a href="#dd"><tt>Depend</tt>, <tt>Debug</tt>, & + <tt>Release</tt> directories</a></li> + <li><a href="#include"><tt>llvm/include</tt></a> </li> + <li><a href="#lib"><tt>llvm/lib</tt></a> </li> + <li><a href="#test"><tt>llvm/test</tt></a> </li> + <li><a href="#tools"><tt>llvm/tools</tt></a> </li> + </ol> + </li> + <li><a href="#tutorial">An example using the LLVM tool chain</a> + </li> + <li><a href="#links">Links</a> </li> +</ul> + <!--=====================================================================--> + +<center> +<h2><a name="overview"><b>Overview</b></a></h2> + </center> + <!--=====================================================================--> + +<p>The <a href="" starting="">next section</a> of this guide is meant to +get you up and running with LLVM, and to give you some basic information +about the LLVM environment. The <a href="" #quickstart="">first subsection</a> +gives a short summary for those who are already familiar with the system +and want to get started as quickly as possible. </p> +<p>The later sections of this guide describe the <a href="" #layout="">general +layout</a> of the LLVM source-tree, a <a href="#tutorial">simple example</a> +using the LLVM tool chain, and <a href="#links">links</a> to find more information +about LLVM or to get help via e-mail. <!--=====================================================================--> + </p> +<center> +<h2><a name="starting"><b>Getting Started</b></a></h2> + </center> + <!--=====================================================================--> + <!--=====================================================================--> + +<h3><a name="quickstart"><b>Getting Started Quickly (A Summary)</b></a></h3> + <!--=====================================================================--> + Here's the short story for getting up and running quickly with LLVM: + +<ol> + <li>Find the path to the CVS repository containing LLVM (we'll call +this <i>CVSROOTDIR</i>). </li> + <li><tt>cd <i>where-you-want-llvm-to-live</i></tt> </li> + <li><tt>cvs -d <i>CVSROOTDIR</i> checkout llvm</tt> </li> + <li><tt>cd llvm</tt> </li> + <li>Edit <tt>Makefile.config</tt> to set local paths. This includes + setting the install location of the C frontend and the various paths + to the C and C++ compilers used to build LLVM itself. </li> + <li>Set your LLVM_LIB_SEARCH_PATH environment variable. </li> + <li><tt>gmake -k |& tee gnumake.out # this is +csh or tcsh syntax</tt> </li> +</ol> + +<p>See <a href="#environment">Setting up your environment</a> on tips to + simplify working with the LLVM front-end and compiled tools. See the + other sub-sections below for other useful details in working with LLVM, + or go straight to <a href="#layout">Program Layout</a> to learn about +the layout of the source code tree. <!-------------------------------------------------------------------------> + </p> +<h3><a name="terminology">Terminology and Notation</a></h3> + <!-------------------------------------------------------------------------> + +<p>Through this manual, the following names are used to denote paths +specific to the local system and working environment. <i>These are not + environment variables you need to set, but just strings used in the rest + of this document below</i>. In any of the examples below, simply replace + each of these names with the appropriate pathname on your local system. All these paths are absolute:</p> - <ul> - </ul> - - <!-------------------------------------------------------------------------> - <h3><a name="checkout">Checkout LLVM from CVS</a></h3> - <!-------------------------------------------------------------------------> - - <p>Before checking out the source code, you will need to know the path to - CVS repository containing LLVM source code (we'll call this - <i>CVSROOTDIR</i> below). Ask the person responsible for your local LLVM - installation to give you this path. - - <p>To get a fresh copy of the entire source code, all you - need to do is check it out from CVS as follows: - <ul> - <li><tt>cd <i>where-you-want-llvm-to-live</i></tt> - <li><tt>cvs -d <i>CVSROOTDIR</i> checkout llvm</tt></p> - </ul> - - <p>This will create an '<tt>llvm</tt>' directory in the current - directory and fully populate it with the LLVM source code, Makefiles, - test directories, and local copies of documentation files.</p> - - <!-------------------------------------------------------------------------> - <h3><a name="config">Local Configuration Options</a></h3> - <!-------------------------------------------------------------------------> - - <p>The file <tt>llvm/Makefile.config</tt> - defines the following path variables, - which are specific to a particular installation of LLVM. - These should need to be modified only once after checking out a copy - of LLVM (if the default values do not already match your system): - - <ul> - <p><li><i>CXX</i> = Path to C++ compiler to use. - <p><li><i>LLVM_OBJ_DIR</i> = Path to the llvm directory where - object files should be placed. - (See the Section on <a href=#objfiles> - The location for LLVM object files</a> - for more information.) - <p><li><i>LLVMGCCDIR</i> = Path to the location of the LLVM front-end - binaries and associated libraries. - <p><li><i>PURIFY</i> = Path to the purify program. - </ul> - - In addition to settings in this file, you must set a - <tt>LLVM_LIB_SEARCH_PATH</tt> environment variable in your startup scripts. - This environment variable is used to locate "system" libraries like - "<tt>-lc</tt>" and "<tt>-lm</tt>" when linking. This variable should be set - to the absolute path for the bytecode-libs subdirectory of the C front-end - install. For example, - <tt>/home/vadve/lattner/local/x86/llvm-gcc/bytecode-libs</tt> for the X86 - version of the C front-end, on our research machines.<p> - - <!-------------------------------------------------------------------------> - <h3><a name="objfiles">The location for LLVM object files</a></h3> - <!-------------------------------------------------------------------------> - - <p>The LLVM make system sends most output files generated during the build - into the directory defined by the variable LLVM_OBJ_DIR in - <tt>llvm/Makefile.config</tt>. This can be either just your normal LLVM - source tree or some other directory writable by you. You may wish to put - object files on a different filesystem either to keep them from being backed - up or to speed up local builds. - - <p>If you do not wish to use a different location for object files (building - into the source tree directly), just set this variable to ".".<p> - - <!-------------------------------------------------------------------------> - <h3><a name="environment">Setting up your environment</a></h3> - <!-------------------------------------------------------------------------> - - <i>NOTE: This step is optional but will set up your environment so you - can use the compiled LLVM tools with as little hassle as - possible.</i>) - - <p>Add the following lines to your <tt>.cshrc</tt> (or the corresponding - lines to your <tt>.profile</tt> if you use a bourne shell derivative). - - <pre> - # Make the C front end easy to use... - alias llvmgcc <i>LLVMGCCDIR</i><tt>/bin/llvm-gcc</tt> + +<ul> + +</ul> + <!-------------------------------------------------------------------------> + +<h3><a name="checkout">Checkout LLVM from CVS</a></h3> + <!-------------------------------------------------------------------------> + +<p>Before checking out the source code, you will need to know the path to + the CVS repository containing LLVM source code (we'll call this <i>CVSROOTDIR</i> +below). Ask the person responsible for your local LLVM installation +to give you this path. </p> +<p>To get a fresh copy of the entire source code, all you need to do +is check it out from CVS as follows: </p> +<ul> + <li><tt>cd <i>where-you-want-llvm-to-live</i></tt> </li> + <li><tt>cvs -d <i>CVSROOTDIR</i> checkout llvm</tt> + <p></p> + </li> +</ul> + +<p>This will create an '<tt>llvm</tt>' directory in the current directory +and fully populate it with the LLVM source code, Makefiles, test directories, +and local copies of documentation files.</p> + <!-------------------------------------------------------------------------> + +<h3><a name="config">Local Configuration Options</a></h3> + <!-------------------------------------------------------------------------> + +<p>The file <tt>llvm/Makefile.config</tt> defines the following path +variables which are specific to a particular installation of LLVM. + These should need to be modified only once after checking out a copy + of LLVM (if the default values do not already match your system): +</p> +<ul> + + <p></p> + <li><i>CXX</i> = Path to C++ compiler to use. + <p></p> + </li> + <li><i>OBJ_ROOT</i> = Path to the llvm directory where object files +should be placed. (See the Section on <a href="#objfiles"> The +location for LLVM object files</a> for more information.) + <p></p> + </li> + <li><i>LLVMGCCDIR</i> = Path to the location of the LLVM front-end +binaries and associated libraries. + <p></p> + </li> + <li><i>PURIFY</i> = Path to the purify program. </li> +</ul> + In addition to settings in this file, you must set a <tt>LLVM_LIB_SEARCH_PATH</tt> +environment variable in your startup scripts. This environment variable +is used to locate "system" libraries like "<tt>-lc</tt>" and "<tt>-lm</tt>" +when linking. This variable should be set to the absolute path for the +bytecode-libs subdirectory of the C front-end install. For example, + <tt>/home/vadve/lattner/local/x86/llvm-gcc/bytecode-libs</tt> is used +for the X86 version of the C front-end on our research machines. +<p> <!-------------------------------------------------------------------------> + </p> +<h3><a name="objfiles">The location for LLVM object files</a></h3> + <!-------------------------------------------------------------------------> + +<p>The LLVM make system sends most output files generated during the build + into the directory defined by the variable OBJ_ROOT in <tt>llvm/Makefile.config</tt>. + This can be either just your normal LLVM source tree or some other directory +writable by you. You may wish to put object files on a different filesystem +either to keep them from being backed up or to speed up local builds. + </p> +<p>If you do not wish to use a different location for object files (i.e. +building into the source tree directly), just set this variable to ".".</p> +<p> <!-------------------------------------------------------------------------> + </p> +<h3><a name="environment">Setting up your environment</a></h3> + <!-------------------------------------------------------------------------> + <i>NOTE: This step is optional but will set up your environment so you + can use the compiled LLVM tools with as little hassle as possible.</i>) + +<p>Add the following lines to your <tt>.cshrc</tt> (or the corresponding + lines to your <tt>.profile</tt> if you use a bourne shell derivative). + </p> +<pre> # Make the C front end easy to use...<br> alias llvmgcc <i>LLVMGCCDIR</i><tt>/bin/llvm-gcc</tt> # Make the LLVM tools easy to use... - setenv PATH <i>LLVM_OBJ_DIR</i>/llvm/tools/Debug:${PATH} - </pre> - The <tt>llvmgcc</tt> alias is useful because the C compiler is not - included in the CVS tree you just checked out. + setenv PATH <i>OBJ_ROOT</i>/llvm/tools/Debug:${PATH}<br> </pre> + The <tt>llvmgcc</tt> alias is useful because the C compiler is not + included in the CVS tree you just checked out. +<p>The other <a href="#tools">LLVM tools</a> are part of the LLVM source +base and are built when compiling LLVM. They will be built into the +<tt><i>OBJ_ROOT</i>/tools/Debug</tt> directory.</p> + <!-------------------------------------------------------------------------> - <p>The other <a href="#tools">LLVM tools</a> are part of the LLVM - source base, and built when compiling LLVM. They will be built into the - <tt><i>LLVM_OBJ_DIR</i>/tools/Debug</tt> directory.</p> - - <!-------------------------------------------------------------------------> - <h3><a name="compile">Compiling the source code</a></h3> - <!-------------------------------------------------------------------------> - - <p>Every directory in the LLVM source tree includes a <tt>Makefile</tt> to - build it, and any subdirectories that it contains. These makefiles require - that you use <tt>gmake</tt>, instead of <tt>make</tt> to build them, but can - otherwise be used freely. To build the entire LLVM system, just enter the - top level <tt>llvm</tt> directory and type <tt>gmake</tt>. A few minutes - later you will hopefully have a freshly compiled toolchain waiting for you - in <tt>llvm/tools/Debug</tt>. If you want to look at the libraries that - were compiled, look in <tt>llvm/lib/Debug</tt>.</p> - - If you get an error talking about a <tt>/localhome</tt> directory, follow - the instructions in the section about <a href="#environment">Setting Up Your - Environment.</a> - - - - <!--=====================================================================--> - <center> - <h2><a name="layout"><b>Program Layout</b></a></h2> - </center> - <!--=====================================================================--> - - <p>One useful source of infomation about the LLVM sourcebase is the LLVM <a - href="http://www.doxygen.org">doxygen</a> documentation, available at <tt><a - href="http://llvm.cs.uiuc.edu/doxygen/">http://llvm.cs.uiuc.edu/doxygen/</a></tt>. The - following is a brief introduction to code layout:</p> - - - <!-------------------------------------------------------------------------> - <h3><a name="cvsdir"><tt>CVS</tt> directories</a></h3> - <!-------------------------------------------------------------------------> - - Every directory checked out of CVS will contain a <tt>CVS</tt> directory, - for the most part these can just be ignored. - - - <!-------------------------------------------------------------------------> - <h3><a name="ddr"><tt>Depend</tt>, <tt>Debug</tt>, & <tt>Release</tt> +<h3><a name="compile">Compiling the source code</a></h3> + <!-------------------------------------------------------------------------> + +<p>Every directory in the LLVM source tree includes a <tt>Makefile</tt> to + build it and any subdirectories that it contains. These makefiles require + GNU Make (<tt>gmake)</tt> instead of <tt>make</tt> to build them, but +can otherwise be used freely. To build the entire LLVM system, just +enter the top level <tt>llvm</tt> directory and type <tt>gmake</tt>. + A few minutes later you will hopefully have a freshly compiled toolchain +waiting for you in <tt><i>OBJ_ROOT</i></tt><tt>/llvm/tools/Debug</tt>. + If you want to look at the libraries that were compiled, look in <tt><i>OBJ_ROOT</i></tt><tt>/llvm/lib/Debug</tt>.</p> + If you get an error about the <tt>/localhome</tt> directory, chances +are good that something has been misconfigured. Follow the instructions +in the section about <a href="#environment">Setting Up Your Environment.</a> + <!--=====================================================================--> + +<center> +<h2><a name="layout"><b>Program Layout</b></a></h2> + </center> + <!--=====================================================================--> + +<p>One useful source of infomation about the LLVM sourcebase is the LLVM +<a href="http://www.doxygen.org">doxygen</a> documentation, available at +<tt><a href="http://llvm.cs.uiuc.edu/doxygen/">http://llvm.cs.uiuc.edu/doxygen/</a></tt>. +The following is a brief introduction to code layout:</p> + <!-------------------------------------------------------------------------> + +<h3><a name="cvsdir"><tt>CVS</tt> directories</a></h3> + <!-------------------------------------------------------------------------> + Every directory checked out of CVS will contain a <tt>CVS</tt> directory; + for the most part, these can just be ignored. <!-------------------------------------------------------------------------> + +<h3><a name="ddr"><tt>Depend</tt>, <tt>Debug</tt>, & <tt>Release</tt> directories</a></h3> - <!-------------------------------------------------------------------------> - - If you are building with the "<tt>BUILD_ROOT=.</tt>" option enabled in the - <tt>Makefile.common</tt> file, most source directories will contain two - directories, <tt>Depend</tt> and <tt>Debug</tt>. The <tt>Depend</tt> - directory contains automatically generated dependance files which are used - during compilation to make sure that source files get rebuilt if a header - file they use is modified. The <tt>Debug</tt> directory holds the object - files, library files and executables that are used for building a debug - enabled build. The <tt>Release</tt> directory is created to hold the same - files when the <tt>ENABLE_OPTIMIZED=1</tt> flag is passed to <tt>gmake</tt>, - causing an optimized built to be performed.<p> - - - <!-------------------------------------------------------------------------> - <h3><a name="include"><tt>llvm/include</tt></a></h3> - <!-------------------------------------------------------------------------> - - This directory contains public header files exported from the LLVM - library. The two main subdirectories of this directory are:<p> - + <!-------------------------------------------------------------------------> + If you are building with the "<tt>OBJ_ROOT=.</tt>" option enabled in +the <tt>Makefile.config</tt> file, most source directories will contain +two directories, <tt>Depend</tt> and <tt>Debug</tt>. The <tt>Depend</tt> + directory contains automatically generated dependance files which are +used during compilation to make sure that source files get rebuilt if +a header file they use is modified. The <tt>Debug</tt> directory holds +the object files, library files, and executables that are used for building +a debug enabled build. The <tt>Release</tt> directory is created to +hold the same files when the <tt>ENABLE_OPTIMIZED=1</tt> flag is passed +to <tt>gmake</tt>, causing an optimized built to be performed. +<p> <!-------------------------------------------------------------------------> + </p> +<h3><a name="include"><tt>llvm/include</tt></a></h3> + <!-------------------------------------------------------------------------> + This directory contains public header files exported from the LLVM + library. The two main subdirectories of this directory are: +<p> </p> +<ol> + <li><tt>llvm/include/llvm</tt> - This directory contains all of the +LLVM specific header files. This directory also has subdirectories +for different portions of LLVM: <tt>Analysis</tt>, <tt>CodeGen</tt>, + <tt>Reoptimizer</tt>, <tt>Target</tt>, <tt>Transforms</tt>, etc... + </li> + <li><tt>llvm/include/Support</tt> - This directory contains generic + support libraries that are independant of LLVM, but are used by LLVM. + For example, some C++ STL utilities and a Command Line option processing + library. </li> +</ol> + <!-------------------------------------------------------------------------> + +<h3><a name="lib"><tt>llvm/lib</tt></a></h3> + <!-------------------------------------------------------------------------> + This directory contains most source files of LLVM system. In LLVM almost +all code exists in libraries, making it very easy to share code among +the different <a href="#tools">tools</a>. +<p> </p> +<dl compact="compact"> + <dt><tt>llvm/lib/VMCore/</tt></dt> + <dd> This directory holds the core LLVM source files that implement +core classes like Instruction and BasicBlock. </dd> + <dt><tt>llvm/lib/AsmParser/</tt></dt> + <dd> This directory holds the source code for the LLVM assembly language +parser library. </dd> + <dt><tt>llvm/lib/ByteCode/</tt></dt> + <dd> This directory holds code for reading and write LLVM bytecode. + </dd> + <dt><tt>llvm/lib/CWriter/</tt></dt> + <dd> This directory implements the LLVM to C converter. </dd> + <dt><tt>llvm/lib/Analysis/</tt></dt> + <dd> This directory contains a variety of different program analyses, +such as Dominator Information, Call Graphs, Induction Variables, Interval +Identification, Natural Loop Identification, etc... </dd> + <dt><tt>llvm/lib/Transforms/</tt></dt> + <dd> This directory contains the source code for the LLVM to LLVM +program transformations, such as Aggressive Dead Code Elimination, +Sparse Conditional Constant Propagation, Inlining, Loop Invarient Code +Motion, Dead Global Elimination, Pool Allocation, and many others... + </dd> + <dt><tt>llvm/lib/Target/</tt></dt> + <dd> This directory contains files that describe various target architectures +for code generation. For example, the llvm/lib/Target/Sparc directory +holds the Sparc machine description.<br> + </dd> + <dt><tt>llvm/lib/CodeGen/</tt></dt> + <dd> This directory contains the major parts of the code generator: +Instruction Selector, Instruction Scheduling, and Register Allocation. + </dd> + <dt><tt>llvm/lib/Reoptimizer/</tt></dt> + <dd> This directory holds code related to the runtime reoptimizer +framework that is currently under development. </dd> + <dt><tt>llvm/lib/Support/</tt></dt> + <dd> This directory contains the source code that corresponds to +the header files located in <tt>llvm/include/Support/</tt>. </dd> +</dl> + <!-------------------------------------------------------------------------> + +<h3><a name="test"><tt>llvm/test</tt></a></h3> + <!-------------------------------------------------------------------------> + +<p>This directory contains regression tests and source code that is used +to test the LLVM infrastructure...</p> + <!-------------------------------------------------------------------------> + +<h3><a name="tools"><tt>llvm/tools</tt></a></h3> + <!-------------------------------------------------------------------------> + +<p>The <b>tools</b> directory contains the executables built out of the + libraries above, which form the main part of the user interface. You +can always get help for a tool by typing <tt>tool_name --help</tt>. +The following is a brief introduction to the most important tools.</p> + +<dl compact="compact"> + <dt><tt><b>as</b></tt></dt> + <dd>The assembler transforms the human readable LLVM assembly to +LLVM bytecode. + <p> </p> + </dd> + <dt><tt><b>dis</b></tt></dt> + <dd>The disassembler transforms the LLVM bytecode to human readable +LLVM assembly. Additionally it can convert LLVM bytecode to C, which +is enabled with the <tt>-c</tt> option. + <p> </p> + </dd> + <dt><tt><b>lli</b></tt></dt> + <dd> <tt>lli</tt> is the LLVM interpreter, which can directly execute +LLVM bytecode (although very slowly...). In addition to a simple intepreter, + <tt>lli</tt> is also has debugger and tracing modes (entered by +specifying <tt>-debug</tt> or <tt>-trace</tt> on the command line, +respectively). + <p> </p> + </dd> + <dt><tt><b>llc</b></tt></dt> + <dd> <tt>llc</tt> is the LLVM backend compiler, which translates +LLVM bytecode to a SPARC assembly file. + <p> </p> + </dd> + <dt><tt><b>llvmgcc</b></tt></dt> + <dd> <tt>llvmgcc</tt> is a GCC based C frontend that has been retargeted +to emit LLVM code as the machine code output. It works just like any +other GCC compiler, taking the typical <tt>-c, -S, -E, -o</tt> options +that are typically used. The source code for the <tt>llvmgcc</tt> +tool is currently not included in the LLVM cvs tree because it is quite +large and not very interesting. + <p> </p> <ol> - <li><tt>llvm/include/llvm</tt> - This directory contains all of the LLVM - specific header files. This directory also has subdirectories for - different portions of LLVM: <tt>Analysis</tt>, <tt>CodeGen</tt>, - <tt>Reoptimizer</tt>, <tt>Target</tt>, <tt>Transforms</tt>, etc... - - <li><tt>llvm/include/Support</tt> - This directory contains generic - support libraries that are independant of LLVM, but are used by LLVM. - For example, some C++ STL utilities and a Command Line option processing - library. + <dt><tt><b>gccas</b></tt></dt> + <dd> This tool is invoked by the <tt>llvmgcc</tt> frontend +as the "assembler" part of the compiler. This tool actually assembles +LLVM assembly to LLVM bytecode, performs a variety of optimizations, + and outputs LLVM bytecode. Thus when you invoke <tt>llvmgcc -c x.c +-o x.o</tt>, you are causing <tt>gccas</tt> to be run, which writes +the <tt>x.o</tt> file (which is an LLVM bytecode file that can be + disassembled or manipulated just like any other bytecode file). +The command line interface to <tt>gccas</tt> is designed to be as +close as possible to the <b>system</b> '<tt>as</tt>' utility so that +the gcc frontend itself did not have to be modified to interface +to a "wierd" assembler. + <p> </p> + </dd> + <dt><tt><b>gccld</b></tt></dt> + <dd> <tt>gccld</tt> links together several LLVM bytecode files +into one bytecode file and does some optimization. It is the linker +invoked by the gcc frontend when multiple .o files need to be linked +together. Like <tt>gccas</tt> the command line interface of <tt>gccld</tt> +is designed to match the system linker, to aid interfacing with the +GCC frontend. + <p> </p> + </dd> </ol> - - <!-------------------------------------------------------------------------> - <h3><a name="lib"><tt>llvm/lib</tt></a></h3> - <!-------------------------------------------------------------------------> - - This directory contains most source files of LLVM system. In LLVM almost all - code exists in libraries, making it very easy to share code among the - different <a href="#tools">tools</a>.<p> - - <dl compact> - <dt><tt>llvm/lib/VMCore/</tt><dd> This directory holds the core LLVM - source files that implement core classes like Instruction and BasicBlock. - - <dt><tt>llvm/lib/AsmParser/</tt><dd> This directory holds the source code - for the LLVM assembly language parser library. - - <dt><tt>llvm/lib/ByteCode/</tt><dd> This directory holds code for reading - and write LLVM bytecode. - - <dt><tt>llvm/lib/CWriter/</tt><dd> This directory implements the LLVM to C - converter. - - <dt><tt>llvm/lib/Analysis/</tt><dd> This directory contains a variety of - different program analyses, such as Dominator Information, Call Graphs, - Induction Variables, Interval Identification, Natural Loop Identification, - etc... - - <dt><tt>llvm/lib/Transforms/</tt><dd> This directory contains the source - code for the LLVM to LLVM program transformations, such as Aggressive Dead - Code Elimination, Sparse Conditional Constant Propagation, Inlining, Loop - Invarient Code Motion, Dead Global Elimination, Pool Allocation, and many - others... - - <dt><tt>llvm/lib/Target/</tt><dd> This directory contains files that - describe various target architectures for code generation. For example, - the llvm/lib/Target/Sparc directory holds the Sparc machine - description.<br> - - <dt><tt>llvm/lib/CodeGen/</tt><dd> This directory contains the major parts - of the code generator: Instruction Selector, Instruction Scheduling, and - Register Allocation. - - <dt><tt>llvm/lib/Reoptimizer/</tt><dd> This directory holds code related - to the runtime reoptimizer framework that is currently under development. - - <dt><tt>llvm/lib/Support/</tt><dd> This directory contains the source code - that corresponds to the header files located in - <tt>llvm/include/Support/</tt>. - </dl> - - <!-------------------------------------------------------------------------> - <h3><a name="test"><tt>llvm/test</tt></a></h3> - <!-------------------------------------------------------------------------> - - <p>This directory contains regression tests and source code that is used to - test the LLVM infrastructure...</p> - - <!-------------------------------------------------------------------------> - <h3><a name="tools"><tt>llvm/tools</tt></a></h3> - <!-------------------------------------------------------------------------> - - <p>The <b>tools</b> directory contains the executables built out of the - libraries a |