forked from OSchip/llvm-project
714 lines
28 KiB
ReStructuredText
714 lines
28 KiB
ReStructuredText
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=================================
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LLVM Testing Infrastructure Guide
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=================================
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Written by John T. Criswell, Daniel Dunbar, Reid Spencer, and Tanya
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Lattner
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.. contents::
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:local:
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Overview
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========
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This document is the reference manual for the LLVM testing
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infrastructure. It documents the structure of the LLVM testing
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infrastructure, the tools needed to use it, and how to add and run
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tests.
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Requirements
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============
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In order to use the LLVM testing infrastructure, you will need all of
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the software required to build LLVM, as well as
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`Python <http://python.org>`_ 2.4 or later.
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LLVM testing infrastructure organization
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========================================
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The LLVM testing infrastructure contains two major categories of tests:
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regression tests and whole programs. The regression tests are contained
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inside the LLVM repository itself under ``llvm/test`` and are expected
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to always pass -- they should be run before every commit.
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The whole programs tests are referred to as the "LLVM test suite" (or
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"test-suite") and are in the ``test-suite`` module in subversion. For
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historical reasons, these tests are also referred to as the "nightly
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tests" in places, which is less ambiguous than "test-suite" and remains
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in use although we run them much more often than nightly.
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Regression tests
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----------------
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The regression tests are small pieces of code that test a specific
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feature of LLVM or trigger a specific bug in LLVM. They are usually
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written in LLVM assembly language, but can be written in other languages
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if the test targets a particular language front end (and the appropriate
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``--with-llvmgcc`` options were used at ``configure`` time of the
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``llvm`` module). These tests are driven by the 'lit' testing tool,
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which is part of LLVM.
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These code fragments are not complete programs. The code generated from
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them is never executed to determine correct behavior.
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These code fragment tests are located in the ``llvm/test`` directory.
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Typically when a bug is found in LLVM, a regression test containing just
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enough code to reproduce the problem should be written and placed
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somewhere underneath this directory. In most cases, this will be a small
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piece of LLVM assembly language code, often distilled from an actual
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application or benchmark.
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``test-suite``
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--------------
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The test suite contains whole programs, which are pieces of code which
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can be compiled and linked into a stand-alone program that can be
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executed. These programs are generally written in high level languages
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such as C or C++.
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These programs are compiled using a user specified compiler and set of
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flags, and then executed to capture the program output and timing
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information. The output of these programs is compared to a reference
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output to ensure that the program is being compiled correctly.
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In addition to compiling and executing programs, whole program tests
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serve as a way of benchmarking LLVM performance, both in terms of the
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efficiency of the programs generated as well as the speed with which
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LLVM compiles, optimizes, and generates code.
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The test-suite is located in the ``test-suite`` Subversion module.
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Debugging Information tests
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---------------------------
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The test suite contains tests to check quality of debugging information.
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The test are written in C based languages or in LLVM assembly language.
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These tests are compiled and run under a debugger. The debugger output
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is checked to validate of debugging information. See README.txt in the
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test suite for more information . This test suite is located in the
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``debuginfo-tests`` Subversion module.
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Quick start
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===========
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The tests are located in two separate Subversion modules. The
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regressions tests are in the main "llvm" module under the directory
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``llvm/test`` (so you get these tests for free with the main llvm tree).
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Use "make check-all" to run the regression tests after building LLVM.
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The more comprehensive test suite that includes whole programs in C and
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C++ is in the ``test-suite`` module. See ```test-suite``
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Quickstart <#testsuitequickstart>`_ for more information on running
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these tests.
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Regression tests
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----------------
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To run all of the LLVM regression tests, use master Makefile in the
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``llvm/test`` directory:
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.. code-block:: bash
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% gmake -C llvm/test
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or
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.. code-block:: bash
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% gmake check
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If you have `Clang <http://clang.llvm.org/>`_ checked out and built, you
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can run the LLVM and Clang tests simultaneously using:
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or
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.. code-block:: bash
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% gmake check-all
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To run the tests with Valgrind (Memcheck by default), just append
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``VG=1`` to the commands above, e.g.:
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.. code-block:: bash
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% gmake check VG=1
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To run individual tests or subsets of tests, you can use the 'llvm-lit'
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script which is built as part of LLVM. For example, to run the
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'Integer/BitPacked.ll' test by itself you can run:
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.. code-block:: bash
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% llvm-lit ~/llvm/test/Integer/BitPacked.ll
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or to run all of the ARM CodeGen tests:
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.. code-block:: bash
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% llvm-lit ~/llvm/test/CodeGen/ARM
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For more information on using the 'lit' tool, see 'llvm-lit --help' or
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the 'lit' man page.
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Debugging Information tests
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---------------------------
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To run debugging information tests simply checkout the tests inside
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clang/test directory.
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.. code-block:: bash
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% cd clang/test
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% svn co http://llvm.org/svn/llvm-project/debuginfo-tests/trunk debuginfo-tests
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These tests are already set up to run as part of clang regression tests.
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Regression test structure
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=========================
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The LLVM regression tests are driven by 'lit' and are located in the
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``llvm/test`` directory.
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This directory contains a large array of small tests that exercise
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various features of LLVM and to ensure that regressions do not occur.
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The directory is broken into several sub-directories, each focused on a
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particular area of LLVM. A few of the important ones are:
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- ``Analysis``: checks Analysis passes.
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- ``Archive``: checks the Archive library.
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- ``Assembler``: checks Assembly reader/writer functionality.
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- ``Bitcode``: checks Bitcode reader/writer functionality.
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- ``CodeGen``: checks code generation and each target.
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- ``Features``: checks various features of the LLVM language.
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- ``Linker``: tests bitcode linking.
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- ``Transforms``: tests each of the scalar, IPO, and utility transforms
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to ensure they make the right transformations.
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- ``Verifier``: tests the IR verifier.
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Writing new regression tests
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----------------------------
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The regression test structure is very simple, but does require some
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information to be set. This information is gathered via ``configure``
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and is written to a file, ``lit.site.cfg`` in ``llvm/test``. The
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``llvm/test`` Makefile does this work for you.
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In order for the regression tests to work, each directory of tests must
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have a ``lit.local.cfg`` file. Lit looks for this file to determine how
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to run the tests. This file is just Python code and thus is very
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flexible, but we've standardized it for the LLVM regression tests. If
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you're adding a directory of tests, just copy ``lit.local.cfg`` from
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another directory to get running. The standard ``lit.local.cfg`` simply
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specifies which files to look in for tests. Any directory that contains
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only directories does not need the ``lit.local.cfg`` file. Read the `Lit
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documentation <http://llvm.org/cmds/lit.html>`_ for more information.
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The ``llvm-runtests`` function looks at each file that is passed to it
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and gathers any lines together that match "RUN:". These are the "RUN"
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lines that specify how the test is to be run. So, each test script must
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contain RUN lines if it is to do anything. If there are no RUN lines,
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the ``llvm-runtests`` function will issue an error and the test will
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fail.
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RUN lines are specified in the comments of the test program using the
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keyword ``RUN`` followed by a colon, and lastly the command (pipeline)
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to execute. Together, these lines form the "script" that
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``llvm-runtests`` executes to run the test case. The syntax of the RUN
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lines is similar to a shell's syntax for pipelines including I/O
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redirection and variable substitution. However, even though these lines
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may *look* like a shell script, they are not. RUN lines are interpreted
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directly by the Tcl ``exec`` command. They are never executed by a
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shell. Consequently the syntax differs from normal shell script syntax
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in a few ways. You can specify as many RUN lines as needed.
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lit performs substitution on each RUN line to replace LLVM tool names
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with the full paths to the executable built for each tool (in
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$(LLVM\_OBJ\_ROOT)/$(BuildMode)/bin). This ensures that lit does not
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invoke any stray LLVM tools in the user's path during testing.
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Each RUN line is executed on its own, distinct from other lines unless
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its last character is ``\``. This continuation character causes the RUN
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line to be concatenated with the next one. In this way you can build up
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long pipelines of commands without making huge line lengths. The lines
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ending in ``\`` are concatenated until a RUN line that doesn't end in
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``\`` is found. This concatenated set of RUN lines then constitutes one
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execution. Tcl will substitute variables and arrange for the pipeline to
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be executed. If any process in the pipeline fails, the entire line (and
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test case) fails too.
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Below is an example of legal RUN lines in a ``.ll`` file:
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.. code-block:: llvm
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; RUN: llvm-as < %s | llvm-dis > %t1
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; RUN: llvm-dis < %s.bc-13 > %t2
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; RUN: diff %t1 %t2
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As with a Unix shell, the RUN: lines permit pipelines and I/O
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redirection to be used. However, the usage is slightly different than
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for Bash. To check what's legal, see the documentation for the `Tcl
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exec <http://www.tcl.tk/man/tcl8.5/TclCmd/exec.htm#M2>`_ command and the
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`tutorial <http://www.tcl.tk/man/tcl8.5/tutorial/Tcl26.html>`_. The
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major differences are:
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- You can't do ``2>&1``. That will cause Tcl to write to a file named
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``&1``. Usually this is done to get stderr to go through a pipe. You
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can do that in tcl with ``|&`` so replace this idiom:
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``... 2>&1 | grep`` with ``... |& grep``
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- You can only redirect to a file, not to another descriptor and not
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from a here document.
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- tcl supports redirecting to open files with the @ syntax but you
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shouldn't use that here.
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There are some quoting rules that you must pay attention to when writing
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your RUN lines. In general nothing needs to be quoted. Tcl won't strip
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off any quote characters so they will get passed to the invoked program.
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For example:
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.. code-block:: bash
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... | grep 'find this string'
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This will fail because the ' characters are passed to grep. This would
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instruction grep to look for ``'find`` in the files ``this`` and
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``string'``. To avoid this use curly braces to tell Tcl that it should
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treat everything enclosed as one value. So our example would become:
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.. code-block:: bash
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... | grep {find this string}
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Additionally, the characters ``[`` and ``]`` are treated specially by
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Tcl. They tell Tcl to interpret the content as a command to execute.
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Since these characters are often used in regular expressions this can
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have disastrous results and cause the entire test run in a directory to
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fail. For example, a common idiom is to look for some basicblock number:
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.. code-block:: bash
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... | grep bb[2-8]
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This, however, will cause Tcl to fail because its going to try to
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execute a program named "2-8". Instead, what you want is this:
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.. code-block:: bash
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... | grep {bb\[2-8\]}
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Finally, if you need to pass the ``\`` character down to a program, then
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it must be doubled. This is another Tcl special character. So, suppose
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you had:
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.. code-block:: bash
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... | grep 'i32\*'
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This will fail to match what you want (a pointer to i32). First, the
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``'`` do not get stripped off. Second, the ``\`` gets stripped off by
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Tcl so what grep sees is: ``'i32*'``. That's not likely to match
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anything. To resolve this you must use ``\\`` and the ``{}``, like this:
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.. code-block:: bash
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... | grep {i32\\*}
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If your system includes GNU ``grep``, make sure that ``GREP_OPTIONS`` is
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not set in your environment. Otherwise, you may get invalid results
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(both false positives and false negatives).
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The FileCheck utility
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---------------------
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A powerful feature of the RUN: lines is that it allows any arbitrary
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commands to be executed as part of the test harness. While standard
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(portable) unix tools like 'grep' work fine on run lines, as you see
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above, there are a lot of caveats due to interaction with Tcl syntax,
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and we want to make sure the run lines are portable to a wide range of
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systems. Another major problem is that grep is not very good at checking
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to verify that the output of a tools contains a series of different
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output in a specific order. The FileCheck tool was designed to help with
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these problems.
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FileCheck (whose basic command line arguments are described in `the
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FileCheck man page <http://llvm.org/cmds/FileCheck.html>`_ is designed
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to read a file to check from standard input, and the set of things to
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verify from a file specified as a command line argument. A simple
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example of using FileCheck from a RUN line looks like this:
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.. code-block:: llvm
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; RUN: llvm-as < %s | llc -march=x86-64 | FileCheck %s
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This syntax says to pipe the current file ("%s") into llvm-as, pipe that
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into llc, then pipe the output of llc into FileCheck. This means that
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FileCheck will be verifying its standard input (the llc output) against
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the filename argument specified (the original .ll file specified by
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"%s"). To see how this works, let's look at the rest of the .ll file
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(after the RUN line):
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.. code-block:: llvm
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define void @sub1(i32* %p, i32 %v) {
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entry:
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; CHECK: sub1:
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; CHECK: subl
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%0 = tail call i32 @llvm.atomic.load.sub.i32.p0i32(i32* %p, i32 %v)
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ret void
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}
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define void @inc4(i64* %p) {
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entry:
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; CHECK: inc4:
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; CHECK: incq
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%0 = tail call i64 @llvm.atomic.load.add.i64.p0i64(i64* %p, i64 1)
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ret void
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}
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Here you can see some "CHECK:" lines specified in comments. Now you can
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see how the file is piped into llvm-as, then llc, and the machine code
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output is what we are verifying. FileCheck checks the machine code
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output to verify that it matches what the "CHECK:" lines specify.
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The syntax of the CHECK: lines is very simple: they are fixed strings
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that must occur in order. FileCheck defaults to ignoring horizontal
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whitespace differences (e.g. a space is allowed to match a tab) but
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otherwise, the contents of the CHECK: line is required to match some
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thing in the test file exactly.
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One nice thing about FileCheck (compared to grep) is that it allows
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merging test cases together into logical groups. For example, because
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the test above is checking for the "sub1:" and "inc4:" labels, it will
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not match unless there is a "subl" in between those labels. If it
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existed somewhere else in the file, that would not count: "grep subl"
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matches if subl exists anywhere in the file.
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The FileCheck -check-prefix option
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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The FileCheck -check-prefix option allows multiple test configurations
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to be driven from one .ll file. This is useful in many circumstances,
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for example, testing different architectural variants with llc. Here's a
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simple example:
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.. code-block:: llvm
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; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin9 -mattr=sse41 \
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; RUN: | FileCheck %s -check-prefix=X32
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; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 -mattr=sse41 \
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; RUN: | FileCheck %s -check-prefix=X64
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define <4 x i32> @pinsrd_1(i32 %s, <4 x i32> %tmp) nounwind {
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%tmp1 = insertelement <4 x i32> %tmp, i32 %s, i32 1
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ret <4 x i32> %tmp1
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; X32: pinsrd_1:
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; X32: pinsrd $1, 4(%esp), %xmm0
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; X64: pinsrd_1:
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; X64: pinsrd $1, %edi, %xmm0
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}
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In this case, we're testing that we get the expected code generation
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with both 32-bit and 64-bit code generation.
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||
|
The "CHECK-NEXT:" directive
|
||
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||
|
|
||
|
Sometimes you want to match lines and would like to verify that matches
|
||
|
happen on exactly consecutive lines with no other lines in between them.
|
||
|
In this case, you can use CHECK: and CHECK-NEXT: directives to specify
|
||
|
this. If you specified a custom check prefix, just use "<PREFIX>-NEXT:".
|
||
|
For example, something like this works as you'd expect:
|
||
|
|
||
|
.. code-block:: llvm
|
||
|
|
||
|
define void @t2(<2 x double>* %r, <2 x double>* %A, double %B) {
|
||
|
%tmp3 = load <2 x double>* %A, align 16
|
||
|
%tmp7 = insertelement <2 x double> undef, double %B, i32 0
|
||
|
%tmp9 = shufflevector <2 x double> %tmp3,
|
||
|
<2 x double> %tmp7,
|
||
|
<2 x i32> < i32 0, i32 2 >
|
||
|
store <2 x double> %tmp9, <2 x double>* %r, align 16
|
||
|
ret void
|
||
|
|
||
|
; CHECK: t2:
|
||
|
; CHECK: movl 8(%esp), %eax
|
||
|
; CHECK-NEXT: movapd (%eax), %xmm0
|
||
|
; CHECK-NEXT: movhpd 12(%esp), %xmm0
|
||
|
; CHECK-NEXT: movl 4(%esp), %eax
|
||
|
; CHECK-NEXT: movapd %xmm0, (%eax)
|
||
|
; CHECK-NEXT: ret
|
||
|
}
|
||
|
|
||
|
CHECK-NEXT: directives reject the input unless there is exactly one
|
||
|
newline between it an the previous directive. A CHECK-NEXT cannot be the
|
||
|
first directive in a file.
|
||
|
|
||
|
The "CHECK-NOT:" directive
|
||
|
^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||
|
|
||
|
The CHECK-NOT: directive is used to verify that a string doesn't occur
|
||
|
between two matches (or the first match and the beginning of the file).
|
||
|
For example, to verify that a load is removed by a transformation, a
|
||
|
test like this can be used:
|
||
|
|
||
|
.. code-block:: llvm
|
||
|
|
||
|
define i8 @coerce_offset0(i32 %V, i32* %P) {
|
||
|
store i32 %V, i32* %P
|
||
|
|
||
|
%P2 = bitcast i32* %P to i8*
|
||
|
%P3 = getelementptr i8* %P2, i32 2
|
||
|
|
||
|
%A = load i8* %P3
|
||
|
ret i8 %A
|
||
|
; CHECK: @coerce_offset0
|
||
|
; CHECK-NOT: load
|
||
|
; CHECK: ret i8
|
||
|
}
|
||
|
|
||
|
FileCheck Pattern Matching Syntax
|
||
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||
|
|
||
|
The CHECK: and CHECK-NOT: directives both take a pattern to match. For
|
||
|
most uses of FileCheck, fixed string matching is perfectly sufficient.
|
||
|
For some things, a more flexible form of matching is desired. To support
|
||
|
this, FileCheck allows you to specify regular expressions in matching
|
||
|
strings, surrounded by double braces: **{{yourregex}}**. Because we want
|
||
|
to use fixed string matching for a majority of what we do, FileCheck has
|
||
|
been designed to support mixing and matching fixed string matching with
|
||
|
regular expressions. This allows you to write things like this:
|
||
|
|
||
|
.. code-block:: llvm
|
||
|
|
||
|
; CHECK: movhpd {{[0-9]+}}(%esp), {{%xmm[0-7]}}
|
||
|
|
||
|
In this case, any offset from the ESP register will be allowed, and any
|
||
|
xmm register will be allowed.
|
||
|
|
||
|
Because regular expressions are enclosed with double braces, they are
|
||
|
visually distinct, and you don't need to use escape characters within
|
||
|
the double braces like you would in C. In the rare case that you want to
|
||
|
match double braces explicitly from the input, you can use something
|
||
|
ugly like **{{[{][{]}}** as your pattern.
|
||
|
|
||
|
FileCheck Variables
|
||
|
^^^^^^^^^^^^^^^^^^^
|
||
|
|
||
|
It is often useful to match a pattern and then verify that it occurs
|
||
|
again later in the file. For codegen tests, this can be useful to allow
|
||
|
any register, but verify that that register is used consistently later.
|
||
|
To do this, FileCheck allows named variables to be defined and
|
||
|
substituted into patterns. Here is a simple example:
|
||
|
|
||
|
.. code-block:: llvm
|
||
|
|
||
|
; CHECK: test5:
|
||
|
; CHECK: notw [[REGISTER:%[a-z]+]]
|
||
|
; CHECK: andw {{.*}}[[REGISTER]]
|
||
|
|
||
|
The first check line matches a regex (``%[a-z]+``) and captures it into
|
||
|
the variables "REGISTER". The second line verifies that whatever is in
|
||
|
REGISTER occurs later in the file after an "andw". FileCheck variable
|
||
|
references are always contained in ``[[ ]]`` pairs, are named, and their
|
||
|
names can be formed with the regex "``[a-zA-Z][a-zA-Z0-9]*``". If a
|
||
|
colon follows the name, then it is a definition of the variable, if not,
|
||
|
it is a use.
|
||
|
|
||
|
FileCheck variables can be defined multiple times, and uses always get
|
||
|
the latest value. Note that variables are all read at the start of a
|
||
|
"CHECK" line and are all defined at the end. This means that if you have
|
||
|
something like "``CHECK: [[XYZ:.*]]x[[XYZ]]``" that the check line will
|
||
|
read the previous value of the XYZ variable and define a new one after
|
||
|
the match is performed. If you need to do something like this you can
|
||
|
probably take advantage of the fact that FileCheck is not actually
|
||
|
line-oriented when it matches, this allows you to define two separate
|
||
|
CHECK lines that match on the same line.
|
||
|
|
||
|
Variables and substitutions
|
||
|
---------------------------
|
||
|
|
||
|
With a RUN line there are a number of substitutions that are permitted.
|
||
|
In general, any Tcl variable that is available in the ``substitute``
|
||
|
function (in ``test/lib/llvm.exp``) can be substituted into a RUN line.
|
||
|
To make a substitution just write the variable's name preceded by a $.
|
||
|
Additionally, for compatibility reasons with previous versions of the
|
||
|
test library, certain names can be accessed with an alternate syntax: a
|
||
|
% prefix. These alternates are deprecated and may go away in a future
|
||
|
version.
|
||
|
|
||
|
Here are the available variable names. The alternate syntax is listed in
|
||
|
parentheses.
|
||
|
|
||
|
``$test`` (``%s``)
|
||
|
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.
|
||
|
|
||
|
``%(line)``, ``%(line+<number>)``, ``%(line-<number>)``
|
||
|
The number of the line where this variable is used, with an optional
|
||
|
integer offset. This can be used in tests with multiple RUN: lines,
|
||
|
which reference test file's line numbers.
|
||
|
|
||
|
``$srcdir``
|
||
|
The source directory from where the "``make check``" was run.
|
||
|
|
||
|
``objdir``
|
||
|
The object directory that corresponds to the ``$srcdir``.
|
||
|
|
||
|
``subdir``
|
||
|
A partial path from the ``test`` directory that contains the
|
||
|
sub-directory that contains the test source being executed.
|
||
|
|
||
|
``srcroot``
|
||
|
The root directory of the LLVM src tree.
|
||
|
|
||
|
``objroot``
|
||
|
The root directory of the LLVM object tree. This could be the same as
|
||
|
the srcroot.
|
||
|
|
||
|
``path``
|
||
|
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.
|
||
|
|
||
|
``tmp``
|
||
|
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.
|
||
|
|
||
|
``target_triplet`` (``%target_triplet``)
|
||
|
The target triplet that corresponds to the current host machine (the one
|
||
|
running the test cases). This should probably be called "host".
|
||
|
|
||
|
``link`` (``%link``)
|
||
|
This full link command used to link LLVM executables. This has all the
|
||
|
configured -I, -L and -l options.
|
||
|
|
||
|
``shlibext`` (``%shlibext``)
|
||
|
The suffix for the host platforms share library (dll) files. This
|
||
|
includes the period as the first character.
|
||
|
|
||
|
To add more variables, two things need to be changed. First, add a line
|
||
|
in the ``test/Makefile`` that creates the ``site.exp`` file. This will
|
||
|
"set" the variable as a global in the site.exp file. Second, in the
|
||
|
``test/lib/llvm.exp`` 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.
|
||
|
|
||
|
Other Features
|
||
|
--------------
|
||
|
|
||
|
To make RUN line writing easier, there are several shell scripts located
|
||
|
in the ``llvm/test/Scripts`` directory. This directory is in the PATH
|
||
|
when running tests, so you can just call these scripts using their name.
|
||
|
For example:
|
||
|
|
||
|
``ignore``
|
||
|
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
|
||
|
``not``
|
||
|
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.
|
||
|
|
||
|
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 ``XFAIL:``
|
||
|
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 the testing tool. To specify an expected fail, use the XFAIL keyword
|
||
|
in the comments of the test program followed by a colon and one or more
|
||
|
failure patterns. Each failure pattern can be either ``*`` (to specify
|
||
|
fail everywhere), or a part of a target triple (indicating the test
|
||
|
should fail on that platform), or the name of a configurable feature
|
||
|
(for example, ``loadable_module``). If there is a match, the test is
|
||
|
expected to fail. If not, the test is expected to succeed. To XFAIL
|
||
|
everywhere just specify ``XFAIL: *``. Here is an example of an ``XFAIL``
|
||
|
line:
|
||
|
|
||
|
.. code-block:: llvm
|
||
|
|
||
|
; XFAIL: darwin,sun
|
||
|
|
||
|
To make the output more useful, the ``llvm_runtest`` 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 number 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.
|
||
|
|
||
|
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.
|
||
|
|
||
|
``test-suite`` Overview
|
||
|
=======================
|
||
|
|
||
|
The ``test-suite`` module contains a number of programs that can be
|
||
|
compiled and executed. The ``test-suite`` includes reference outputs for
|
||
|
all of the programs, so that the output of the executed program can be
|
||
|
checked for correctness.
|
||
|
|
||
|
``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. When using ``LNT``, use the
|
||
|
``--test-externals`` option to include these tests in the results.
|
||
|
|
||
|
``test-suite`` Quickstart
|
||
|
-------------------------
|
||
|
|
||
|
The modern way of running the ``test-suite`` is focused on testing and
|
||
|
benchmarking complete compilers using the
|
||
|
`LNT <http://llvm.org/docs/lnt>`_ testing infrastructure.
|
||
|
|
||
|
For more information on using LNT to execute the ``test-suite``, please
|
||
|
see the `LNT Quickstart <http://llvm.org/docs/lnt/quickstart.html>`_
|
||
|
documentation.
|
||
|
|
||
|
``test-suite`` Makefiles
|
||
|
------------------------
|
||
|
|
||
|
Historically, the ``test-suite`` was executed using a complicated setup
|
||
|
of Makefiles. The LNT based approach above is recommended for most
|
||
|
users, but there are some testing scenarios which are not supported by
|
||
|
the LNT approach. In addition, LNT currently uses the Makefile setup
|
||
|
under the covers and so developers who are interested in how LNT works
|
||
|
under the hood may want to understand the Makefile based setup.
|
||
|
|
||
|
For more information on the ``test-suite`` Makefile setup, please see
|
||
|
the `Test Suite Makefile Guide. <TestSuiteMakefileGuide.html>`_
|