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            <div class="doc_title">

            
              LLVM Test Suite Guide

            
            </div>


            <ol>

            
              <li><a href="#overview">Overview</a></li>

            
              <li><a href="#Requirements">Requirements</a></li>

            
              <li><a href="#quick">Quick Start</a></li>

            
              <li><a href="#org">LLVM Test Suite Organization</a>

            
                <ul>

            
                  <li><a href="#codefragments">Code Fragments</a></li>

            
                  <li><a href="#wholeprograms">Whole Programs</a></li>

            
                </ul>

            
              </li>

            
              <li><a href="#tree">LLVM Test Suite Tree</a></li>

            
              <li><a href="#dgstructure">DejaGNU Structure</a></li>

            
              <li><a href="#progstructure"><tt>llvm-test</tt> Structure</a></li>

            
              <li><a href="#run">Running the LLVM Tests</a>

            
                <ul>

            
                  <li><a href="#customtest">Writing custom tests for llvm-test</a></li>

            
                </ul>

            
              </li>

            
              <li><a href="#nightly">Running the nightly tester</a></li>

            
            </ol>


            <div class="doc_author">

            
              <p>Written by John T. Criswell, <a

            
              href="http://llvm.x10sys.com/rspencer">Reid Spencer</a>, and Tanya Lattner</p>

            
            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="overview">Overview</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


            <p>This document is the reference manual for the LLVM test suite.  It documents

            
            the structure of the LLVM test suite, the tools needed to use it, and how to add

            
            and run tests.</p>


            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="Requirements">Requirements</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


            <p>In order to use the LLVM test suite, you will need all of the software

            
            required to build LLVM, plus the following:</p>


            <dl>

            
            <dt><a href="http://www.gnu.org/software/dejagnu/">DejaGNU</a></dt>

            
            <dd>The Feature and Regressions tests are organized and run by DejaGNU.</dd>

            
            <dt><a href="http://expect.nist.gov/">Expect</a></dt>

            
            <dd>Expect is required by DejaGNU.</dd>

            
            <dt><a href="http://www.tcl.tk/software/tcltk/">tcl</a></dt>

            
            <dd>Tcl is required by DejaGNU. </dd>


            <dt><a href="http://www.netlib.org/f2c">F2C</a></dt>

            
            <dd>For now, LLVM does not have a Fortran front-end, but using F2C, we can run

            
            Fortran benchmarks.  F2C support must be enabled via <tt>configure</tt> if not

            
            installed in a standard place.  F2C requires three items: the <tt>f2c</tt>

            
            executable, <tt>f2c.h</tt> to compile the generated code, and <tt>libf2c.a</tt>

            
            to link generated code.  By default, given an F2C directory <tt>$DIR</tt>, the

            
            configure script will search <tt>$DIR/bin</tt> for <tt>f2c</tt>,

            
            <tt>$DIR/include</tt> for <tt>f2c.h</tt>, and <tt>$DIR/lib</tt> for

            
            <tt>libf2c.a</tt>.  The default <tt>$DIR</tt> values are: <tt>/usr</tt>,

            
            <tt>/usr/local</tt>, <tt>/sw</tt>, and <tt>/opt</tt>.  If you installed F2C in a

            
            different location, you must tell <tt>configure</tt>:


            <ul>

            
            <li><tt>./configure --with-f2c=$DIR</tt><br>

            
            This will specify a new <tt>$DIR</tt> for the above-described search

            
            process.  This will only work if the binary, header, and library are in their

            
            respective subdirectories of <tt>$DIR</tt>.</li>


            <li><tt>./configure --with-f2c-bin=/binary/path --with-f2c-inc=/include/path

            
            --with-f2c-lib=/lib/path</tt><br>

            
            This allows you to specify the F2C components separately.  Note: if you choose

            
            this route, you MUST specify all three components, and you need to only specify

            
            <em>directories</em> where the files are located; do NOT include the

            
            filenames themselves on the <tt>configure</tt> line.</li>

            
            </ul></dd>

            
            </dl>


            <p>Darwin (Mac OS X) developers can simplify the installation of Expect and tcl

            
            by using fink.  <tt>fink install expect</tt> will install both. Alternatively,

            
            Darwinports users can use <tt>sudo port install expect</tt> to install Expect

            
            and tcl.</p>


            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="quick">Quick Start</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


              <p>The tests are located in two separate Subversion modules. The basic feature

            
              and regression tests are in the main "llvm" module under the directory

            
              <tt>llvm/test</tt>. A more comprehensive test suite that includes whole

            
            programs in C and C++ is in the <tt>test-suite</tt> module. This module should

            
            be checked out to the <tt>llvm/projects</tt> directory as llvm-test (for

            
            historical purpose).  When you <tt>configure</tt> the <tt>llvm</tt> module,

            
            the <tt>llvm-test</tt> directory will be automatically configured.

            
            Alternatively, you can configure the <tt>test-suite</tt> module manually.</p>

            
            <p>To run all of the simple tests in LLVM using DejaGNU, use the master Makefile

            
             in the <tt>llvm/test</tt> directory:</p>


            <div class="doc_code">

            
            <pre>

            
            % gmake -C llvm/test

            
            </pre>

            
            </div>


            <p>or</p>


            <div class="doc_code">

            
            <pre>

            
            % gmake check

            
            </pre>

            
            </div>


            <p>To run only a subdirectory of tests in llvm/test using DejaGNU (ie.

            
            Regression/Transforms), just set the TESTSUITE variable to the path of the

            
            subdirectory (relative to <tt>llvm/test</tt>):</p>


            <div class="doc_code">

            
            <pre>

            
            % gmake -C llvm/test TESTSUITE=Regression/Transforms

            
            </pre>

            
            </div>


            <p><b>Note: If you are running the tests with <tt>objdir != subdir</tt>, you

            
            must have run the complete testsuite before you can specify a

            
            subdirectory.</b></p>


            <p>To run the comprehensive test suite (tests that compile and execute whole

            
            programs), run the <tt>llvm-test</tt> tests:</p>


            <div class="doc_code">

            
            <pre>

            
            % cd llvm/projects

            
            % svn co http://llvm.org/svn/llvm-project/test-suite/trunk llvm-test

            
            % cd ..

            
            % ./configure --with-llvmgccdir=$LLVM_GCC_DIR

            
            % cd projects/llvm-test

            
            % gmake

            
            </pre>

            
            </div>


            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="org">LLVM Test Suite Organization</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


            <p>The LLVM test suite contains two major categories of tests: code

            
            fragments and whole programs. Code fragments are in the <tt>llvm</tt> module

            
            under the <tt>llvm/test</tt> directory. The whole programs

            
            test suite is in the <tt>llvm-test</tt> module under the main directory.</p>


            </div>


            <!-- _______________________________________________________________________ -->

            
            <div class="doc_subsection"><a name="codefragments">Code Fragments</a></div>

            
            <!-- _______________________________________________________________________ -->


            <div class="doc_text">


            <p>Code fragments are small pieces of code that test a specific feature of LLVM

            
            or trigger a specific bug in LLVM.  They are usually written in LLVM assembly

            
            language, but can be written in other languages if the test targets a particular

            
            language front end.</p>


            <p>Code fragments are not complete programs, and they are never executed to

            
            determine correct behavior.</p>


            <p>These code fragment tests are located in the <tt>llvm/test/Features</tt> and

            
            <tt>llvm/test/Regression</tt> directories.</p>


            </div>


            <!-- _______________________________________________________________________ -->

            
            <div class="doc_subsection"><a name="wholeprograms">Whole Programs</a></div>

            
            <!-- _______________________________________________________________________ -->


            <div class="doc_text">


            <p>Whole Programs are pieces of code which can be compiled and linked into a

            
            stand-alone program that can be executed.  These programs are generally written

            
            in high level languages such as C or C++, but sometimes they are written

            
            straight in LLVM assembly.</p>


            <p>These programs are compiled and then executed using several different

            
            methods (native compiler, LLVM C backend, LLVM JIT, LLVM native code generation,

            
            etc).  The output of these programs is compared to ensure that LLVM is compiling

            
            the program correctly.</p>


            <p>In addition to compiling and executing programs, whole program tests serve as

            
            a way of benchmarking LLVM performance, both in terms of the efficiency of the

            
            programs generated as well as the speed with which LLVM compiles, optimizes, and

            
            generates code.</p>


            <p>All "whole program" tests are located in the <tt>test-suite</tt> Subversion

            
            module.</p>


            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="tree">LLVM Test Suite Tree</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


            <p>Each type of test in the LLVM test suite has its own directory. The major

            
            subtrees of the test suite directory tree are as follows:</p>


            <ul>

            
              <li><tt>llvm/test</tt>

            
              <p>This directory contains a large array of small tests

            
              that exercise various features of LLVM and to ensure that regressions do not

            
              occur. The directory is broken into several sub-directories, each focused on

            
              a particular area of LLVM. A few of the important ones are:</p>

            
              <ul>

            
                <li><tt>Analysis</tt>: checks Analysis passes.</li>

            
                <li><tt>Archive</tt>: checks the Archive library.</li>

            
                <li><tt>Assembler</tt>: checks Assembly reader/writer functionality.</li>

            
                <li><tt>Bitcode</tt>: checks Bitcode reader/writer functionality.</li>

            
                <li><tt>CodeGen</tt>: checks code generation and each target.</li>

            
                <li><tt>Features</tt>: checks various features of the LLVM language.</li>

            
                <li><tt>Linker</tt>: tests bitcode linking.</li>

            
                <li><tt>Transforms</tt>: tests each of the scalar, IPO, and utility

            
                transforms to ensure they make the right transformations.</li>

            
                <li><tt>Verifier</tt>: tests the IR verifier.</li>

            
              </ul>

            
              <p>Typically when a bug is found in LLVM, a regression test containing

            
              just enough code to reproduce the problem should be written and placed

            
              somewhere underneath this directory.  In most cases, this will be a small

            
              piece of LLVM assembly language code, often distilled from an actual

            
              application or benchmark.</p></li>


            <li><tt>test-suite</tt>

            
            <p>The <tt>test-suite</tt> module contains programs that can be compiled

            
            with LLVM and executed.  These programs are compiled using the native compiler

            
            and various LLVM backends.  The output from the program compiled with the

            
            native compiler is assumed correct; the results from the other programs are

            
            compared to the native program output and pass if they match.</p>


            <p>In addition for testing correctness, the <tt>llvm-test</tt> directory also

            
            performs timing tests of various LLVM optimizations.  It also records

            
            compilation times for the compilers and the JIT.  This information can be

            
            used to compare the effectiveness of LLVM's optimizations and code

            
            generation.</p></li>


            <li><tt>llvm-test/SingleSource</tt>

            
            <p>The SingleSource directory contains test programs that are only a single

            
            source file in size.  These are usually small benchmark programs or small

            
            programs that calculate a particular value.  Several such programs are grouped

            
            together in each directory.</p></li>


            <li><tt>llvm-test/MultiSource</tt>

            
            <p>The MultiSource directory contains subdirectories which contain entire

            
            programs with multiple source files.  Large benchmarks and whole applications

            
            go here.</p></li>


            <li><tt>llvm-test/External</tt>

            
            <p>The External directory contains Makefiles for building code that is external

            
            to (i.e., not distributed with) LLVM.  The most prominent members of this

            
            directory are the SPEC 95 and SPEC 2000 benchmark suites.  The presence and

            
            location of these external programs is configured by the llvm-test

            
            <tt>configure</tt> script.</p></li>


            </ul>


            </div>

            
            <!--=========================================================================-->

            
            <div class="doc_section"><a name="dgstructure">DejaGNU Structure</a></div>

            
            <!--=========================================================================-->

            
            <div class="doc_text">

            
              <p>The LLVM test suite is partially driven by DejaGNU and partially driven by

            
              GNU Make. Specifically, the Features and Regression tests are all driven by

            
              DejaGNU. The <tt>llvm-test</tt> module is currently driven by a set of

            
              Makefiles.</p>


              <p>The DejaGNU structure is very simple, but does require some information to

            
              be set. This information is gathered via <tt>configure</tt> and is written

            
              to a file, <tt>site.exp</tt> in <tt>llvm/test</tt>. The <tt>llvm/test</tt>

            
              Makefile does this work for you.</p>


              <p>In order for DejaGNU to work, each directory of tests must have a

            
              <tt>dg.exp</tt> file. DejaGNU looks for this file to determine how to run the

            
              tests. This file is just a Tcl script and it can do anything you want, but

            
              we've standardized it for the LLVM regression tests. It simply loads a Tcl

            
              library (<tt>test/lib/llvm.exp</tt>) and calls the <tt>llvm_runtests</tt>

            
              function defined in that library with a list of file names to run. The names

            
              are obtained by using Tcl's glob command.  Any directory that contains only

            
              directories does not need the <tt>dg.exp</tt> file.</p>


              <p>The <tt>llvm-runtests</tt> function lookas at each file that is passed to

            
              it and gathers any lines together that match "RUN:". This are the "RUN" lines

            
              that specify how the test is to be run. So, each test script must contain

            
              RUN lines if it is to do anything. If there are no RUN lines, the

            
              <tt>llvm-runtests</tt> function will issue an error and the test will

            
              fail.</p>


              <p>RUN lines are specified in the comments of the test program using the

            
              keyword <tt>RUN</tt> followed by a colon, and lastly the command (pipeline)

            
              to execute.  Together, these lines form the "script" that

            
              <tt>llvm-runtests</tt> executes to run the test case.  The syntax of the

            
              RUN lines is similar to a shell's syntax for pipelines including I/O

            
              redirection and variable substitution.  However, even though these lines

            
              may <i>look</i> like a shell script, they are not. RUN lines are interpreted

            
              directly by the Tcl <tt>exec</tt> command. They are never executed by a

            
              shell. Consequently the syntax differs from normal shell script syntax in a

            
              few ways.  You can specify as many RUN lines as needed.</p>


              <p>Each RUN line is executed on its own, distinct from other lines unless

            
              its last character is <tt>\</tt>. This continuation character causes the RUN

            
              line to be concatenated with the next one. In this way you can build up long

            
              pipelines of commands without making huge line lengths. The lines ending in

            
              <tt>\</tt> are concatenated until a RUN line that doesn't end in <tt>\</tt> is

            
              found. This concatenated set or RUN lines then constitutes one execution.

            
              Tcl will substitute variables and arrange for the pipeline to be executed. If

            
              any process in the pipeline fails, the entire line (and test case) fails too.

            
              </p>


              <p> Below is an example of legal RUN lines in a <tt>.ll</tt> file:</p>


            <div class="doc_code">

            
            <pre>

            
            ; RUN: llvm-as &lt; %s | llvm-dis &gt; %t1

            
            ; RUN: llvm-dis &lt; %s.bc-13 &gt; %t2

            
            ; RUN: diff %t1 %t2

            
            </pre>

            
            </div>


              <p>As with a Unix shell, the RUN: lines permit pipelines and I/O redirection

            
              to be used. However, the usage is slightly different than for Bash. To check

            
              what's legal, see the documentation for the

            
              <a href="http://www.tcl.tk/man/tcl8.5/TclCmd/exec.htm#M2">Tcl exec</a>

            
              command and the

            
              <a href="http://www.tcl.tk/man/tcl8.5/tutorial/Tcl26.html">tutorial</a>.

            
              The major differences are:</p>

            
              <ul>

            
                <li>You can't do <tt>2&gt;&amp;1</tt>. That will cause Tcl to write to a

            
                file named <tt>&amp;1</tt>. Usually this is done to get stderr to go through

            
                a pipe. You can do that in tcl with <tt>|&amp;</tt> so replace this idiom:

            
                <tt>... 2&gt;&amp;1 | grep</tt> with <tt>... |&amp; grep</tt></li>

            
                <li>You can only redirect to a file, not to another descriptor and not from

            
                a here document.</li>

            
                <li>tcl supports redirecting to open files with the @ syntax but you

            
                shouldn't use that here.</li>

            
              </ul>


              <p>There are some quoting rules that you must pay attention to when writing

            
              your RUN lines. In general nothing needs to be quoted. Tcl won't strip off any

            
              ' or " so they will get passed to the invoked program. For example:</p>


            <div class="doc_code">

            
            <pre>

            
            ... | grep 'find this string'

            
            </pre>

            
            </div>


              <p>This will fail because the ' characters are passed to grep. This would

            
              instruction grep to look for <tt>'find</tt> in the files <tt>this</tt> and

            
              <tt>string'</tt>. To avoid this use curly braces to tell Tcl that it should

            
              treat everything enclosed as one value. So our example would become:</p>


            <div class="doc_code">

            
            <pre>

            
            ... | grep {find this string}

            
            </pre>

            
            </div>


              <p>Additionally, the characters <tt>[</tt> and <tt>]</tt> are treated

            
              specially by Tcl. They tell Tcl to interpret the content as a command to

            
              execute. Since these characters are often used in regular expressions this can

            
              have disastrous results and cause the entire test run in a directory to fail.

            
              For example, a common idiom is to look for some basicblock number:</p>


            <div class="doc_code">

            
            <pre>

            
            ... | grep bb[2-8]

            
            </pre>

            
            </div>


              <p>This, however, will cause Tcl to fail because its going to try to execute

            
              a program named "2-8". Instead, what you want is this:</p>


            <div class="doc_code">

            
            <pre>

            
            ... | grep {bb\[2-8\]}

            
            </pre>

            
            </div>


              <p>Finally, if you need to pass the <tt>\</tt> character down to a program,

            
              then it must be doubled. This is another Tcl special character. So, suppose

            
              you had:


            <div class="doc_code">

            
            <pre>

            
            ... | grep 'i32\*'

            
            </pre>

            
            </div>


              <p>This will fail to match what you want (a pointer to i32). First, the

            
              <tt>'</tt> do not get stripped off. Second, the <tt>\</tt> gets stripped off

            
              by Tcl so what grep sees is: <tt>'i32*'</tt>. That's not likely to match

            
              anything. To resolve this you must use <tt>\\</tt> and the <tt>{}</tt>, like

            
              this:</p>


            <div class="doc_code">

            
            <pre>

            
            ... | grep {i32\\*}

            
            </pre>

            
            </div>


            </div>


            <!-- _______________________________________________________________________ -->

            
            <div class="doc_subsection"><a name="dgvars">Vars And Substitutions</a></div>

            
            <div class="doc_text">

            
              <p>With a RUN line there are a number of substitutions that are permitted. In

            
              general, any Tcl variable that is available in the <tt>substitute</tt>

            
              function (in <tt>test/lib/llvm.exp</tt>) can be substituted into a RUN line.

            
              To make a substitution just write the variable's name preceded by a $.

            
              Additionally, for compatibility reasons with previous versions of the test

            
              library, certain names can be accessed with an alternate syntax: a % prefix.

            
              These alternates are deprecated and may go away in a future version.

            
              </p>

            
              <p>Here are the available variable names. The alternate syntax is listed in

            
              parentheses.</p>


              <dl style="margin-left: 25px">

            
                <dt><b>$test</b> (%s)</dt>

            
                <dd>The full path to the test case's source. This is suitable for passing

            
                on the command line as the input to an llvm tool.</dd>


                <dt><b>$srcdir</b></dt>

            
                <dd>The source directory from where the "<tt>make check</tt>" was run.</dd>


                <dt><b>objdir</b></dt>

            
                <dd>The object directory that corresponds to the <tt>$srcdir</tt>.</dd>


                <dt><b>subdir</b></dt>

            
                <dd>A partial path from the <tt>test</tt> directory that contains the

            
                sub-directory that contains the test source being executed.</dd>


                <dt><b>srcroot</b></dt>

            
                <dd>The root directory of the LLVM src tree.</dd>


                <dt><b>objroot</b></dt>

            
                <dd>The root directory of the LLVM object tree. This could be the same

            
                as the srcroot.</dd>


                <dt><b>path</b><dt>

            
                <dd>The path to the directory that contains the test case source.  This is

            
                for locating any supporting files that are not generated by the test, but

            
                used by the test.</dd>


                <dt><b>tmp</b></dt>

            
                <dd>The path to a temporary file name that could be used for this test case.

            
                The file name won't conflict with other test cases. You can append to it if

            
                you need multiple temporaries. This is useful as the destination of some

            
                redirected output.</dd>


                <dt><b>llvmlibsdir</b> (%llvmlibsdir)</dt>

            
                <dd>The directory where the LLVM libraries are located.</dd>


                <dt><b>target_triplet</b> (%target_triplet)</dt>

            
                <dd>The target triplet that corresponds to the current host machine (the one

            
                running the test cases). This should probably be called "host".<dd>


                <dt><b>prcontext</b> (%prcontext)</dt>

            
                <dd>Path to the prcontext tcl script that prints some context around a

            
                line that matches a pattern. This isn't strictly necessary as the test suite

            
                is run with its PATH altered to include the test/Scripts directory where

            
                the prcontext script is located. Note that this script is similar to

            
                <tt>grep -C</tt> but you should use the <tt>prcontext</tt> script because

            
                not all platforms support <tt>grep -C</tt>.</dd>


                <dt><b>llvmgcc</b> (%llvmgcc)</dt>

            
                <dd>The full path to the <tt>llvm-gcc</tt> executable as specified in the

            
                configured LLVM environment</dd>


                <dt><b>llvmgxx</b> (%llvmgxx)</dt>

            
                <dd>The full path to the <tt>llvm-gxx</tt> executable as specified in the

            
                configured LLVM environment</dd>


                <dt><b>llvmgcc_version</b> (%llvmgcc_version)</dt>

            
                <dd>The full version number of the <tt>llvm-gcc</tt> executable.</dd>


                <dt><b>llvmgccmajvers</b> (%llvmgccmajvers)</dt>

            
                <dd>The major version number of the <tt>llvm-gcc</tt> executable.</dd>


                <dt><b>gccpath</b></dt>

            
                <dd>The full path to the C compiler used to <i>build </i> LLVM. Note that

            
                this might not be gcc.</dd>


                <dt><b>gxxpath</b></dt>

            
                <dd>The full path to the C++ compiler used to <i>build </i> LLVM. Note that

            
                this might not be g++.</dd>


                <dt><b>compile_c</b> (%compile_c)</dt>

            
                <dd>The full command line used to compile LLVM C source  code. This has all

            
                the configured -I, -D and optimization options.</dd>


                <dt><b>compile_cxx</b> (%compile_cxx)</dt>

            
                <dd>The full command used to compile LLVM C++ source  code. This has

            
                all the configured -I, -D and optimization options.</dd>


                <dt><b>link</b> (%link)</dt>

            
                <dd>This full link command used to link LLVM executables. This has all the

            
                configured -I, -L and -l options.</dd>


                <dt><b>shlibext</b> (%shlibext)</dt>

            
                <dd>The suffix for the host platforms share library (dll) files. This

            
                includes the period as the first character.</dd>

            
              </dl>

            
              <p>To add more variables, two things need to be changed. First, add a line in

            
              the <tt>test/Makefile</tt> that creates the <tt>site.exp</tt> file. This will

            
              "set" the variable as a global in the site.exp file. Second, in the

            
              <tt>test/lib/llvm.exp</tt> file, in the substitute proc, add the variable name

            
              to the list of "global" declarations at the beginning of the proc. That's it,

            
              the variable can then be used in test scripts.</p>

            
            </div>


            <!-- _______________________________________________________________________ -->

            
            <div class="doc_subsection"><a name="dgfeatures">Other Features</a></div>

            
            <div class="doc_text">

            
              <p>To make RUN line writing easier, there are several shell scripts located

            
              in the <tt>llvm/test/Scripts</tt> directory. For example:</p>

            
              <dl>

            
                <dt><b>ignore</b></dt>

            
                <dd>This script runs its arguments and then always returns 0. This is useful

            
                in cases where the test needs to cause a tool to generate an error (e.g. to

            
                check the error output). However, any program in a pipeline that returns a

            
                non-zero result will cause the test to fail. This script overcomes that

            
                issue and nicely documents that the test case is purposefully ignoring the

            
                result code of the tool</dd>


                <dt><b>not</b></dt>

            
                <dd>This script runs its arguments and then inverts the result code from

            
                it. Zero result codes become 1. Non-zero result codes become 0. This is

            
                useful to invert the result of a grep. For example "not grep X" means

            
                succeed only if you don't find X in the input.</dd>

            
              </dl>


              <p>Sometimes it is necessary to mark a test case as "expected fail" or XFAIL.

            
              You can easily mark a test as XFAIL just by including  <tt>XFAIL: </tt> on a

            
              line near the top of the file. This signals that the test case should succeed

            
              if the test fails. Such test cases are counted separately by DejaGnu. To

            
              specify an expected fail, use the XFAIL keyword in the comments of the test

            
              program followed by a colon and one or more regular expressions (separated by

            
              a comma). The regular expressions allow you to XFAIL the test conditionally

            
              by host platform. The regular expressions following the : are matched against

            
              the target triplet or llvmgcc version number for the host machine. If there is

            
              a match, the test is expected to fail. If not, the test is expected to

            
              succeed. To XFAIL everywhere just specify <tt>XFAIL: *</tt>. When matching

            
              the llvm-gcc version, you can specify the major (e.g. 3) or full version

            
              (i.e. 3.4) number. Here is an example of an <tt>XFAIL</tt> line:</p>


            <div class="doc_code">

            
            <pre>

            
            ; XFAIL: darwin,sun,llvmgcc4

            
            </pre>

            
            </div>


              <p>To make the output more useful, the <tt>llvm_runtest</tt> function wil

            
              scan the lines of the test case for ones that contain a pattern that matches

            
              PR[0-9]+. This is the syntax for specifying a PR (Problem Report) number that

            
              is related to the test case. The numer after "PR" specifies the LLVM bugzilla

            
              number. When a PR number is specified, it will be used in the pass/fail

            
              reporting. This is useful to quickly get some context when a test fails.</p>


              <p>Finally, any line that contains "END." will cause the special

            
              interpretation of lines to terminate. This is generally done right after the

            
              last RUN: line. This has two side effects: (a) it prevents special

            
              interpretation of lines that are part of the test program, not the

            
              instructions to the test case, and (b) it speeds things up for really big test

            
              cases by avoiding interpretation of the remainder of the file.</p>


            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="progstructure"><tt>llvm-test</tt>

            
            Structure</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


            <p>As mentioned previously, the <tt>llvm-test</tt> module  provides three types

            
            of tests: MultiSource, SingleSource, and External.  Each tree is then subdivided

            
            into several categories, including applications, benchmarks, regression tests,

            
            code that is strange grammatically, etc.  These organizations should be

            
            relatively self explanatory.</p>


            <p>In addition to the regular "whole program"  tests, the <tt>llvm-test</tt>

            
            module also provides a mechanism for compiling the programs in different ways.

            
            If the variable TEST is defined on the gmake command line, the test system will

            
            include a Makefile named <tt>TEST.&lt;value of TEST variable&gt;.Makefile</tt>.

            
            This Makefile can modify build rules to yield different results.</p>


            <p>For example, the LLVM nightly tester uses <tt>TEST.nightly.Makefile</tt> to

            
            create the nightly test reports.  To run the nightly tests, run <tt>gmake

            
            TEST=nightly</tt>.</p>


            <p>There are several TEST Makefiles available in the tree.  Some of them are

            
            designed for internal LLVM research and will not work outside of the LLVM

            
            research group.  They may still be valuable, however, as a guide to writing your

            
            own TEST Makefile for any optimization or analysis passes that you develop with

            
            LLVM.</p>


            <p>Note, when configuring the <tt>llvm-test</tt> module, you might want to

            
            specify the following configuration options:</p>

            
            <dl>

            
              <dt><i>--enable-spec2000</i>

            
              <dt><i>--enable-spec2000=&lt;<tt>directory</tt>&gt;</i>

            
              <dd>

            
                Enable the use of SPEC2000 when testing LLVM.  This is disabled by default

            
                (unless <tt>configure</tt> finds SPEC2000 installed).  By specifying

            
                <tt>directory</tt>, you can tell configure where to find the SPEC2000

            
                benchmarks.  If <tt>directory</tt> is left unspecified, <tt>configure</tt>

            
                uses the default value

            
                <tt>/home/vadve/shared/benchmarks/speccpu2000/benchspec</tt>.

            
                <p>


              <dt><i>--enable-spec95</i>

            
              <dt><i>--enable-spec95=&lt;<tt>directory</tt>&gt;</i>

            
              <dd>

            
                Enable the use of SPEC95 when testing LLVM.  It is similar to the

            
                <i>--enable-spec2000</i> option.

            
                <p>


              <dt><i>--enable-povray</i>

            
              <dt><i>--enable-povray=&lt;<tt>directory</tt>&gt;</i>

            
              <dd>

            
                Enable the use of Povray as an external test.  Versions of Povray written

            
                in C should work.  This option is similar to the <i>--enable-spec2000</i>

            
                option.

            
            </dl>

            
            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="run">Running the LLVM Tests</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


            <p>First, all tests are executed within the LLVM object directory tree.  They

            
            <i>are not</i> executed inside of the LLVM source tree. This is because the

            
            test suite creates temporary files during execution.</p>


            <p>The master Makefile in <tt>llvm/test</tt> is capable of running only the

            
            DejaGNU driven tests. By default, it will run all of these tests.</p>


            <p>To run only the DejaGNU driven tests, run <tt>gmake</tt> at the

            
            command line in <tt>llvm/test</tt>.  To run a specific directory of tests, use

            
            the <tt>TESTSUITE</tt> variable.

            
            </p>


            <p>For example, to run the Regression tests, type

            
            <tt>gmake TESTSUITE=Regression</tt> in <tt>llvm/tests</tt>.</p>


            <p>Note that there are no Makefiles in <tt>llvm/test/Features</tt> and

            
            <tt>llvm/test/Regression</tt>. You must use DejaGNU from the <tt>llvm/test</tt>

            
            directory to run them.</p>


            <p>To run the <tt>llvm-test</tt> suite, you need to use the following steps:</p>


            <ol>

            
              <li><tt>cd</tt> into the <tt>llvm/projects</tt> directory</li>


              <li><p>Check out the <tt>test-suite</tt> module with:</p>


            <div class="doc_code">

            
            <pre>

            
            % svn co http://llvm.org/svn/llvm-project/test-suite/trunk llvm-test

            
            </pre>

            
            </div>


                  <p>This will get the test suite into <tt>llvm/projects/llvm-test</tt></p>


              <li><p>Configure the test suite using llvm configure. This will automatically configure llvm-test.

            
                     You must do it from the top level otherwise llvm-gcc will not be set which is required to

            
                    run llvm-test:</p>

            
            <div class="doc_code">

            
            <pre>

            
            % cd $LLVM_OBJ_ROOT ; $LLVM_SRC_ROOT/configure --with-llvmgccdir=$LLVM_GCC_DIR

            
            </pre>

            
            </div>

            
              <li><tt>gmake</tt></li>

            
            </ol>

            
            <p>Note that the second and third steps only need to be done once. After you

            
            have the suite checked out and configured, you don't need to do it again (unless

            
            the test code or configure script changes). $LLVM_GCC_DIR is the path to the LLVM

            
            C/C++ FrontEnd</p>


            <p>To make a specialized test (use one of the

            
            <tt>llvm-test/TEST.&lt;type&gt;.Makefile</tt>s), just run:</p>


            <div class="doc_code">

            
            <pre>

            
            % gmake TEST=&lt;type&gt; test

            
            </pre>

            
            </div>


            <p>For example, you could run the nightly tester tests using the following

            
            commands:</p>


            <div class="doc_code">

            
            <pre>

            
            % cd llvm/projects/llvm-test

            
            % gmake TEST=nightly test

            
            </pre>

            
            </div>


            <p>Regardless of which test you're running, the results are printed on standard

            
            output and standard error.  You can redirect these results to a file if you

            
            choose.</p>


            <p>Some tests are known to fail.  Some are bugs that we have not fixed yet;

            
            others are features that we haven't added yet (or may never add).  In DejaGNU,

            
            the result for such tests will be XFAIL (eXpected FAILure).  In this way, you

            
            can tell the difference between an expected and unexpected failure.</p>


            <p>The tests in <tt>llvm-test</tt> have no such feature at this time. If the

            
            test passes, only warnings and other miscellaneous output will be generated.  If

            
            a test fails, a large &lt;program&gt; FAILED message will be displayed.  This

            
            will help you separate benign warnings from actual test failures.</p>


            </div>


            <!-- _______________________________________________________________________ -->

            
            <div class="doc_subsection">

            
            <a name="customtest">Writing custom tests for llvm-test</a></div>

            
            <!-- _______________________________________________________________________ -->


            <div class="doc_text">


            <p>Assuming you can run llvm-test, (e.g. "<tt>gmake TEST=nightly report</tt>"

            
            should work), it is really easy to run optimizations or code generator

            
            components against every program in the tree, collecting statistics or running

            
            custom checks for correctness.  At base, this is how the nightly tester works,

            
            it's just one example of a general framework.</p>


            <p>Lets say that you have an LLVM optimization pass, and you want to see how

            
            many times it triggers.  First thing you should do is add an LLVM

            
            <a href="ProgrammersManual.html#Statistic">statistic</a> to your pass, which

            
            will tally counts of things you care about.</p>


            <p>Following this, you can set up a test and a report that collects these and

            
            formats them for easy viewing.  This consists of two files, an

            
            "<tt>llvm-test/TEST.XXX.Makefile</tt>" fragment (where XXX is the name of your

            
            test) and an "<tt>llvm-test/TEST.XXX.report</tt>" file that indicates how to

            
            format the output into a table.  There are many example reports of various

            
            levels of sophistication included with llvm-test, and the framework is very

            
            general.</p>


            <p>If you are interested in testing an optimization pass, check out the

            
            "libcalls" test as an example.  It can be run like this:<p>


            <div class="doc_code">

            
            <pre>

            
            % cd llvm/projects/llvm-test/MultiSource/Benchmarks  # or some other level

            
            % make TEST=libcalls report

            
            </pre>

            
            </div>


            <p>This will do a bunch of stuff, then eventually print a table like this:</p>


            <div class="doc_code">

            
            <pre>

            
            Name                                  | total | #exit |

            
            ...

            
            FreeBench/analyzer/analyzer           | 51    | 6     |

            
            FreeBench/fourinarow/fourinarow       | 1     | 1     |

            
            FreeBench/neural/neural               | 19    | 9     |

            
            FreeBench/pifft/pifft                 | 5     | 3     |

            
            MallocBench/cfrac/cfrac               | 1     | *     |

            
            MallocBench/espresso/espresso         | 52    | 12    |

            
            MallocBench/gs/gs                     | 4     | *     |

            
            Prolangs-C/TimberWolfMC/timberwolfmc  | 302   | *     |

            
            Prolangs-C/agrep/agrep                | 33    | 12    |

            
            Prolangs-C/allroots/allroots          | *     | *     |

            
            Prolangs-C/assembler/assembler        | 47    | *     |

            
            Prolangs-C/bison/mybison              | 74    | *     |

            
            ...

            
            </pre>

            
            </div>


            <p>This basically is grepping the -stats output and displaying it in a table.

            
            You can also use the "TEST=libcalls report.html" target to get the table in HTML

            
            form, similarly for report.csv and report.tex.</p>


            <p>The source for this is in llvm-test/TEST.libcalls.*.  The format is pretty

            
            simple: the Makefile indicates how to run the test (in this case,

            
            "<tt>opt -simplify-libcalls -stats</tt>"), and the report contains one line for

            
            each column of the output.  The first value is the header for the column and the

            
            second is the regex to grep the output of the command for.  There are lots of

            
            example reports that can do fancy stuff.</p>


            </div>


            <!--=========================================================================-->

            
            <div class="doc_section"><a name="nightly">Running the nightly tester</a></div>

            
            <!--=========================================================================-->


            <div class="doc_text">


            <p>

            
            The <a href="http://llvm.org/nightlytest/">LLVM Nightly Testers</a>

            
            automatically check out an LLVM tree, build it, run the "nightly"

            
            program test (described above), run all of the feature and regression tests,

            
            delete the checked out tree, and then submit the results to

            
            <a href="http://llvm.org/nightlytest/">http://llvm.org/nightlytest/</a>.

            
            After test results are submitted to

            
            <a href="http://llvm.org/nightlytest/">http://llvm.org/nightlytest/</a>,

            
            they are processed and displayed on the tests page. An email to

            
            <a href="http://lists.cs.uiuc.edu/pipermail/llvm-testresults/">

            
            llvm-testresults@cs.uiuc.edu</a> summarizing the results is also generated.

            
            This testing scheme is designed to ensure that programs don't break as well

            
            as keep track of LLVM's progress over time.</p>


            <p>If you'd like to set up an instance of the nightly tester to run on your

            
            machine, take a look at the comments at the top of the

            
            <tt>utils/NewNightlyTest.pl</tt> file. If you decide to set up a nightly tester

            
            please choose a unique nickname and invoke <tt>utils/NewNightlyTest.pl</tt>

            
            with the "-nickname [yournickname]" command line option.


            <p>You can create a shell script to encapsulate the running of the script.

            
            The optimized x86 Linux nightly test is run from just such a script:</p>


            <div class="doc_code">

            
            <pre>

            
            #!/bin/bash

            
            BASE=/proj/work/llvm/nightlytest

            
            export BUILDDIR=$BASE/build

            
            export WEBDIR=$BASE/testresults

            
            export LLVMGCCDIR=/proj/work/llvm/cfrontend/install

            
            export PATH=/proj/install/bin:$LLVMGCCDIR/bin:$PATH

            
            export LD_LIBRARY_PATH=/proj/install/lib

            
            cd $BASE

            
            cp /proj/work/llvm/llvm/utils/NewNightlyTest.pl .

            
            nice ./NewNightlyTest.pl -nice -release -verbose -parallel -enable-linscan \

            
               -nickname NightlyTester -noexternals &gt; output.log 2&gt;&amp;1

            
            </pre>

            
            </div>


            <p>It is also possible to specify the the location your nightly test results

            
            are submitted. You can do this by passing the command line option

            
            "-submit-server [server_address]" and "-submit-script [script_on_server]" to

            
            <tt>utils/NewNightlyTest.pl</tt>. For example, to submit to the llvm.org

            
            nightly test results page, you would invoke the nightly test script with

            
            "-submit-server llvm.org -submit-script /nightlytest/NightlyTestAccept.cgi".

            
            If these options are not specified, the nightly test script sends the results

            
            to the llvm.org nightly test results page.</p>


            <p>Take a look at the <tt>NewNightlyTest.pl</tt> file to see what all of the

            
            flags and strings do.  If you start running the nightly tests, please let us

            
            know. Thanks!</p>


            </div>


            <!-- *********************************************************************** -->


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