| ============================== |
| LLVM test-suite Makefile Guide |
| ============================== |
| |
| .. contents:: |
| :local: |
| |
| Overview |
| ======== |
| |
| This document describes the features of the Makefile-based LLVM |
| test-suite. This way of interacting with the test-suite is deprecated in |
| favor of running the test-suite using LNT, but may continue to prove |
| useful for some users. See the Testing Guide's :ref:`test-suite Quickstart |
| <test-suite-quickstart>` section for more information. |
| |
| Test suite Structure |
| ==================== |
| |
| The ``test-suite`` module contains a number of 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. |
| |
| When executing tests, it is usually a good idea to start out with a |
| subset of the available tests or programs. This makes test run times |
| smaller at first and later on this is useful to investigate individual |
| test failures. To run some test only on a subset of programs, simply |
| change directory to the programs you want tested and run ``gmake`` |
| there. Alternatively, you can run a different test using the ``TEST`` |
| variable to change what tests or run on the selected programs (see below |
| for more info). |
| |
| In addition for testing correctness, the ``test-suite`` 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. |
| |
| ``test-suite`` tests are divided into three types of tests: MultiSource, |
| SingleSource, and External. |
| |
| - ``test-suite/SingleSource`` |
| |
| 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. |
| |
| - ``test-suite/MultiSource`` |
| |
| The MultiSource directory contains subdirectories which contain |
| entire programs with multiple source files. Large benchmarks and |
| whole applications go here. |
| |
| - ``test-suite/External`` |
| |
| 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 ``External`` directory does not contain these actual |
| tests, but only the Makefiles that know how to properly compile these |
| programs from somewhere else. The presence and location of these |
| external programs is configured by the test-suite ``configure`` |
| script. |
| |
| 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. |
| |
| 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 the |
| regression tests, the result for such tests will be XFAIL (eXpected |
| FAILure). In this way, you can tell the difference between an expected |
| and unexpected failure. |
| |
| The tests in the test suite 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 <program> FAILED message will be |
| displayed. This will help you separate benign warnings from actual test |
| failures. |
| |
| Running the test suite |
| ====================== |
| |
| First, all tests are executed within the LLVM object directory tree. |
| They *are not* executed inside of the LLVM source tree. This is because |
| the test suite creates temporary files during execution. |
| |
| To run the test suite, you need to use the following steps: |
| |
| #. ``cd`` into the ``llvm/projects`` directory in your source tree. |
| #. Check out the ``test-suite`` module with: |
| |
| .. code-block:: bash |
| |
| % svn co http://llvm.org/svn/llvm-project/test-suite/trunk test-suite |
| |
| This will get the test suite into ``llvm/projects/test-suite``. |
| |
| #. Configure and build ``llvm``. |
| |
| #. Configure and build ``llvm-gcc``. |
| |
| #. Install ``llvm-gcc`` somewhere. |
| |
| #. *Re-configure* ``llvm`` from the top level of each build tree (LLVM |
| object directory tree) in which you want to run the test suite, just |
| as you do before building LLVM. |
| |
| During the *re-configuration*, you must either: (1) have ``llvm-gcc`` |
| you just built in your path, or (2) specify the directory where your |
| just-built ``llvm-gcc`` is installed using |
| ``--with-llvmgccdir=$LLVM_GCC_DIR``. |
| |
| You must also tell the configure machinery that the test suite is |
| available so it can be configured for your build tree: |
| |
| .. code-block:: bash |
| |
| % cd $LLVM_OBJ_ROOT ; $LLVM_SRC_ROOT/configure [--with-llvmgccdir=$LLVM_GCC_DIR] |
| |
| [Remember that ``$LLVM_GCC_DIR`` is the directory where you |
| *installed* llvm-gcc, not its src or obj directory.] |
| |
| #. You can now run the test suite from your build tree as follows: |
| |
| .. code-block:: bash |
| |
| % cd $LLVM_OBJ_ROOT/projects/test-suite |
| % make |
| |
| 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). |
| |
| Configuring External Tests |
| -------------------------- |
| |
| In order to run the External tests in the ``test-suite`` module, you |
| must specify *--with-externals*. This must be done during the |
| *re-configuration* step (see above), and the ``llvm`` re-configuration |
| must recognize the previously-built ``llvm-gcc``. If any of these is |
| missing or neglected, the External tests won't work. |
| |
| * *--with-externals* |
| |
| * *--with-externals=<directory>* |
| |
| This tells LLVM where to find any external tests. They are expected to |
| be in specifically named subdirectories of <``directory``>. If |
| ``directory`` is left unspecified, ``configure`` uses the default value |
| ``/home/vadve/shared/benchmarks/speccpu2000/benchspec``. Subdirectory |
| names known to LLVM include: |
| |
| * spec95 |
| |
| * speccpu2000 |
| |
| * speccpu2006 |
| |
| * povray31 |
| |
| Others are added from time to time, and can be determined from |
| ``configure``. |
| |
| Running different tests |
| ----------------------- |
| |
| In addition to the regular "whole program" tests, the ``test-suite`` |
| 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 |
| ``TEST.<value of TEST variable>.Makefile``. This Makefile can modify |
| build rules to yield different results. |
| |
| For example, the LLVM nightly tester uses ``TEST.nightly.Makefile`` to |
| create the nightly test reports. To run the nightly tests, run |
| ``gmake TEST=nightly``. |
| |
| 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. |
| |
| Generating test output |
| ---------------------- |
| |
| There are a number of ways to run the tests and generate output. The |
| most simple one is simply running ``gmake`` with no arguments. This will |
| compile and run all programs in the tree using a number of different |
| methods and compare results. Any failures are reported in the output, |
| but are likely drowned in the other output. Passes are not reported |
| explicitly. |
| |
| Somewhat better is running ``gmake TEST=sometest test``, which runs the |
| specified test and usually adds per-program summaries to the output |
| (depending on which sometest you use). For example, the ``nightly`` test |
| explicitly outputs TEST-PASS or TEST-FAIL for every test after each |
| program. Though these lines are still drowned in the output, it's easy |
| to grep the output logs in the Output directories. |
| |
| Even better are the ``report`` and ``report.format`` targets (where |
| ``format`` is one of ``html``, ``csv``, ``text`` or ``graphs``). The |
| exact contents of the report are dependent on which ``TEST`` you are |
| running, but the text results are always shown at the end of the run and |
| the results are always stored in the ``report.<type>.format`` file (when |
| running with ``TEST=<type>``). The ``report`` also generate a file |
| called ``report.<type>.raw.out`` containing the output of the entire |
| test run. |
| |
| Writing custom tests for the test suite |
| --------------------------------------- |
| |
| Assuming you can run the test suite, (e.g. |
| "``gmake TEST=nightly report``" 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. |
| |
| 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 |
| `statistic <ProgrammersManual.html#Statistic>`_ to your pass, which will |
| tally counts of things you care about. |
| |
| 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, a |
| "``test-suite/TEST.XXX.Makefile``" fragment (where XXX is the name of |
| your test) and a "``test-suite/TEST.XXX.report``" file that indicates |
| how to format the output into a table. There are many example reports of |
| various levels of sophistication included with the test suite, and the |
| framework is very general. |
| |
| If you are interested in testing an optimization pass, check out the |
| "libcalls" test as an example. It can be run like this: |
| |
| .. code-block:: bash |
| |
| % cd llvm/projects/test-suite/MultiSource/Benchmarks # or some other level |
| % make TEST=libcalls report |
| |
| This will do a bunch of stuff, then eventually print a table like this: |
| |
| :: |
| |
| 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 | * | |
| ... |
| |
| 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. |
| |
| The source for this is in ``test-suite/TEST.libcalls.*``. The format is |
| pretty simple: the Makefile indicates how to run the test (in this case, |
| "``opt -simplify-libcalls -stats``"), 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. |