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diff --git a/contrib/llvm/tools/clang/www/hacking.html b/contrib/llvm/tools/clang/www/hacking.html new file mode 100644 index 0000000..3bbc0ea --- /dev/null +++ b/contrib/llvm/tools/clang/www/hacking.html @@ -0,0 +1,270 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" + "http://www.w3.org/TR/html4/strict.dtd"> +<!-- Material used from: HTML 4.01 specs: http://www.w3.org/TR/html401/ --> +<html> +<head> + <META http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" /> + <title>Hacking on clang</title> + <link type="text/css" rel="stylesheet" href="menu.css" /> + <link type="text/css" rel="stylesheet" href="content.css" /> +</head> +<body> +<!--#include virtual="menu.html.incl"--> +<div id="content"> + <!--*********************************************************************--> + <h1>Hacking on Clang</h1> + <!--*********************************************************************--> + + <p>This document provides some hints for how to get started hacking + on Clang for developers who are new to the Clang and/or LLVM + codebases.</p> + <ul> + <li><a href="#style">Coding Standards</a></li> + <li><a href="#docs">Developer Documentation</a></li> + <li><a href="#debugging">Debugging</a></li> + <li><a href="#testing">Testing</a></li> + <ul> + <li><a href="#testingNonWindows">Testing on Unix-like Systems</a></li> + <li><a href="#testingWindows">Testing using Visual Studio on Windows</a></li> + </ul> + <li><a href="#patches">Creating Patch Files</a></li> + <li><a href="#irgen">LLVM IR Generation</a></li> + </ul> + + <!--=====================================================================--> + <h2 id="docs">Coding Standards</h2> + <!--=====================================================================--> + + <p>Clang follows the + LLVM <a href="http://llvm.org/docs/CodingStandards.html">Coding + Standards</a>. When submitting patches, please take care to follow these standards + and to match the style of the code to that present in Clang (for example, in + terms of indentation, bracing, and statement spacing).</p> + + <p>Clang has a few additional coding standards:</p> + <ul> + <li><i>cstdio is forbidden</i>: library code should not output diagnostics + or other information using <tt>cstdio</tt>; debugging routines should + use <tt>llvm::errs()</tt>. Other uses of <tt>cstdio</tt> impose behavior + upon clients and block integrating Clang as a library. Libraries should + support <tt>raw_ostream</tt> based interfaces for textual + output. See <a href="http://llvm.org/docs/CodingStandards.html#ll_raw_ostream">Coding + Standards</a>.</li> + </ul> + + <!--=====================================================================--> + <h2 id="docs">Developer Documentation</h2> + <!--=====================================================================--> + + <p>Both Clang and LLVM use doxygen to provide API documentation. Their + respective web pages (generated nightly) are here:</p> + <ul> + <li><a href="http://clang.llvm.org/doxygen">Clang</a></li> + <li><a href="http://llvm.org/doxygen">LLVM</a></li> + </ul> + + <p>For work on the LLVM IR generation, the LLVM assembly language + <a href="http://llvm.org/docs/LangRef.html">reference manual</a> is + also useful.</p> + + <!--=====================================================================--> + <h2 id="debugging">Debugging</h2> + <!--=====================================================================--> + + <p>Inspecting data structures in a debugger:</p> + <ul> + <li>Many LLVM and Clang data structures provide + a <tt>dump()</tt> method which will print a description of the + data structure to <tt>stderr</tt>.</li> + <li>The <a href="docs/InternalsManual.html#QualType"><tt>QualType</tt></a> + structure is used pervasively. This is a simple value class for + wrapping types with qualifiers; you can use + the <tt>isConstQualified()</tt>, for example, to get one of the + qualifiers, and the <tt>getTypePtr()</tt> method to get the + wrapped <tt>Type*</tt> which you can then dump.</li> + </ul> + + <!--=====================================================================--> + <h2 id="testing">Testing</h2> + <!--=====================================================================--> + + <p><i>[Note: The test running mechanism is currently under revision, so the + following might change shortly.]</i></p> + + <!--=====================================================================--> + <h3 id="testingNonWindows">Testing on Unix-like Systems</h3> + <!--=====================================================================--> + + <p>Clang includes a basic regression suite in the tree which can be + run with <tt>make test</tt> from the top-level clang directory, or + just <tt>make</tt> in the <em>test</em> sub-directory. + <tt>make VERBOSE=1</tt> can be used to show more detail + about what is being run.</p> + + <p>The tests primarily consist of a test runner script running the compiler + under test on individual test files grouped in the directories under the + test directory. The individual test files include comments at the + beginning indicating the Clang compile options to use, to be read + by the test runner. Embedded comments also can do things like telling + the test runner that an error is expected at the current line. + Any output files produced by the test will be placed under + a created Output directory.</p> + + <p>During the run of <tt>make test</tt>, the terminal output will + display a line similar to the following:</p> + + <ul><tt>--- Running clang tests for i686-pc-linux-gnu ---</tt></ul> + + <p>followed by a line continually overwritten with the current test + file being compiled, and an overall completion percentage.</p> + + <p>After the <tt>make test</tt> run completes, the absence of any + <tt>Failing Tests (count):</tt> message indicates that no tests + failed unexpectedly. If any tests did fail, the + <tt>Failing Tests (count):</tt> message will be followed by a list + of the test source file paths that failed. For example:</p> + + <tt><pre> + Failing Tests (3): + /home/john/llvm/tools/clang/test/SemaCXX/member-name-lookup.cpp + /home/john/llvm/tools/clang/test/SemaCXX/namespace-alias.cpp + /home/john/llvm/tools/clang/test/SemaCXX/using-directive.cpp + </pre></tt> + + <p>If you used the <tt>make VERBOSE=1</tt> option, the terminal + output will reflect the error messages from the compiler and + test runner.</p> + + <p>The regression suite can also be run with Valgrind by running + <tt>make test VG=1</tt> in the top-level clang directory.</p> + + <p>For more intensive changes, running + the <a href="http://llvm.org/docs/TestingGuide.html#testsuiterun">LLVM + Test Suite</a> with clang is recommended. Currently the best way to + override LLVMGCC, as in: <tt>make LLVMGCC="clang -std=gnu89" + TEST=nightly report</tt> (make sure <tt>clang</tt> is in your PATH or use the + full path).</p> + + <!--=====================================================================--> + <h3 id="testingWindows">Testing using Visual Studio on Windows</h3> + <!--=====================================================================--> + + <p>The Clang test suite can be run from either Visual Studio or + the command line.</p> + + <p>Note that the test runner is based on + Python, which must be installed. Find Python at: + <a href="http://www.python.org/download">http://www.python.org/download</a>. + Download the latest stable version (2.6.2 at the time of this writing).</p> + + <p>The GnuWin32 tools are also necessary for running the tests. + (Note that the grep from MSYS or Cygwin doesn't work with the tests + because of embedded double-quotes in the search strings. The GNU + grep does work in this case.) + Get them from <a href="http://getgnuwin32.sourceforge.net"> + http://getgnuwin32.sourceforge.net</a>.</p> + + <p>The cmake build tool is set up to create Visual Studio project files + for running the tests, "clang-test" being the root. Therefore, to + run the test from Visual Studio, right-click the clang-test project + and select "Build".</p> + + <p>To run all the tests from the command line, execute a command like + the following:</p> + + <tt> + python (path to llvm)/llvm/utils/lit/lit.py -sv --no-progress-bar + (path to llvm)/llvm/tools/clang/test + </tt> + + <p>To run a single test:</p> + + <tt> + python (path to llvm)/llvm/utils/lit/lit.py -sv --no-progress-bar + (path to llvm)/llvm/tools/clang/test/(dir)/(test) + </tt> + + <p>For example:</p> + + <tt> + python C:/Tools/llvm/utils/lit/lit.py -sv --no-progress-bar + C:/Tools/llvm/tools/clang/test/Sema/wchar.c + </tt> + + <p>The -sv option above tells the runner to show the test output if + any tests failed, to help you determine the cause of failure.</p> + + <p>Note that a few tests currently fail on Windows. We are working to + correct this. Therefore your output might look something like this:</p> + +<tt><pre>lit.py: lit.cfg:152: note: using clang: 'C:/Tools/llvm/bin/Debug\\clang.EXE' +-- Testing: 1723 tests, 2 threads -- +FAIL: Clang::(test path) (659 of 1723) +******************** TEST 'Clang::(test path)' FAILED ******************** +Script: + (commands run) +Command Output (stdout): + (output here) +Command Output (stderr): + (output here) +******************** +Testing Time: 83.66s +******************** +Failing Tests (1): + Clang::(test path) + Expected Passes : 1704 + Expected Failures : 18 + Unexpected Failures: 1 +</pre></tt> + + <p>The last statistic, "Unexpected Failures", is the important one.</p> + + <!--=====================================================================--> + <h2 id="patches">Creating Patch Files</h2> + <!--=====================================================================--> + + <p>To return changes to the Clang team, unless you have checkin + privileges, the prefered way is to send patch files to the + cfe-commits mailing list, with an explanation of what the patch is for. + Or, if you have questions, or want to have a wider discussion of what + you are doing, such as if you are new to Clang development, you can use + the cfe-dev mailing list also. + </p> + + <p>To create these patch files, change directory + to the llvm/tools/clang root and run:</p> + + <ul><tt>svn diff (relative path) >(patch file name)</tt></ul> + + <p>For example, for getting the diffs of all of clang:</p> + + <ul><tt>svn diff . >~/mypatchfile.patch</tt></ul> + + <p>For example, for getting the diffs of a single file:</p> + + <ul><tt>svn diff lib/Parse/ParseDeclCXX.cpp >~/ParseDeclCXX.patch</tt></ul> + + <p>Note that the paths embedded in the patch depend on where you run it, + so changing directory to the llvm/tools/clang directory is recommended.</p> + + <!--=====================================================================--> + <h2 id="irgen">LLVM IR Generation</h2> + <!--=====================================================================--> + + <p>The LLVM IR generation part of clang handles conversion of the + AST nodes output by the Sema module to the LLVM Intermediate + Representation (IR). Historically, this was referred to as + "codegen", and the Clang code for this lives + in <tt>lib/CodeGen</tt>.</p> + + <p>The output is most easily inspected using the <tt>-emit-llvm</tt> + option to clang (possibly in conjunction with <tt>-o -</tt>). You + can also use <tt>-emit-llvm-bc</tt> to write an LLVM bitcode file + which can be processed by the suite of LLVM tools + like <tt>llvm-dis</tt>, <tt>llvm-nm</tt>, etc. See the LLVM + <a href="http://llvm.org/docs/CommandGuide/">Command Guide</a> + for more information.</p> + +</div> +</body> +</html> |
