test-suite Makefile Guide (deprecated)

Overview

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:

  1. Check out the test-suite module with:

    % git clone https://github.com/llvm/llvm-test-suite.git test-suite
    
  2. FIXME: these directions are outdated and won’t work. Figure out what the correct thing to do is, and write it down here.

  3. Configure and build llvm.

  4. Configure and build llvm-gcc.

  5. Install llvm-gcc somewhere.

  6. 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:

    % 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.]

  7. You can now run the test suite from your build tree as follows:

    % 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 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:

% 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.