LLVM Test Suite Guide

+ +

The LLVM testing infrastructure contains two major categories of tests: +regression tests and whole programs. The regression tests are contained inside +the LLVM repository itself under llvm/test and are expected to always +pass -- they should be run before every commit.

+ +

The whole programs tests are referred to as the "LLVM test suite" (or +"test-suite") and are in the test-suite module in subversion. For +historical reasons, these tests are also referred to as the "nightly tests" in +places, which is less ambiguous than "test-suite" and remains in use although we +run them much more often than nightly.

+ + +

Regression tests

+ + +

+ +

The regression tests 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 (and the appropriate --with-llvmgcc +options were used at configure time of the llvm module). These +tests are driven by the 'lit' testing tool, which is part of LLVM.

+ +

These code fragments are not complete programs. The code generated +from them is never executed to determine correct behavior.

+ +

These code fragment tests are located in the llvm/test +directory.

+ +

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.

- -

Overview

- + +

`test-suite`

+ -

+ +

The test suite contains whole programs, which 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++.

+ +

These programs are compiled using a user specified compiler and set of flags, +and then executed to capture the program output and timing information. The +output of these programs is compared to a reference output to ensure that the +program is being compiled correctly.

+ +

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.

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.

The test-suite is located in the test-suite Subversion module.

- -

Requirements

- + +

Debugging Information tests

+ -

In order to use the LLVM test suite, you will need all of the software -required to build LLVM, plus the following:

The test suite contains tests to check quality of debugging information. +The test are written in C based languages or in LLVM assembly language.

QMTest: The LLVM test suite uses QMTest to organize and run tests. Note: - you will need QMTest - 2.0.3 (source tar.gz file) to be successful. The tests do not run with - any other version.
Python: You will need a Python interpreter that works with QMTest. Python will - need zlib and SAX support enabled.

- -

Quick Start

- + +

Quick start

+ -

The tests are located in the LLVM source tree under the directory -llvm/test. To run all of the tests in LLVM, use the Master Makefile in -that directory:

The tests are located in two separate Subversion modules. The regressions + tests are in the main "llvm" module under the directory + llvm/test (so you get these tests for free with the main llvm + tree). Use "make check-all" to run the regression tests after building + LLVM.

The more comprehensive test suite that includes whole programs in C and C++ + is in the test-suite + module. See test-suite Quickstart + for more information on running these tests.

+ + +

Regression tests

+ +

To run all of the LLVM regression tests, use master Makefile in + the llvm/test directory:

+ +

- % gmake -C llvm/test
+% gmake -C llvm/test

To run only the code fragment tests (i.e. those that do basic testing of -LLVM), run the tests organized by QMTest:

- % gmake -C llvm/test qmtest
+% gmake check

+ +

If you have Clang checked out and built, +you can run the LLVM and Clang tests simultaneously using:

To run only the tests that compile and execute whole programs, run the -Programs tests:

- % gmake -C llvm/test/Programs
+% gmake check-all

To run the tests with Valgrind (Memcheck by default), just append +VG=1 to the commands above, e.g.:

+ +

+% gmake check VG=1
+

- -

LLVM Test Suite Organization

- +

To run individual tests or subsets of tests, you can use the 'llvm-lit' +script which is built as part of LLVM. For example, to run the +'Integer/BitCast.ll' test by itself you can run:

+% llvm-lit ~/llvm/test/Integer/BitCast.ll 
+

The LLVM test suite contains two major categories of tests: code -fragments and whole programs.

or to run all of the ARM CodeGen tests:

+% llvm-lit ~/llvm/test/CodeGen/ARM
+

Code Fragments +

For more information on using the 'lit' tool, see 'llvm-lit --help' or the +'lit' man page.

+ +

Debugging Information tests

+ +

To run debugging information tests simply checkout the tests inside +clang/test directory.

+ +

+%cd clang/test
+% svn co http://llvm.org/svn/llvm-project/debuginfo-tests/trunk debuginfo-tests
+

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.

These tests are already set up to run as part of clang regression tests.

Code fragments are not complete programs, and they are never executed to -determine correct behavior.

The tests in the Features and Regression directories contain code -fragments.

Whole Programs

+ +

Regression test structure

+ +

The LLVM regression tests are driven by 'lit' and are located in + the llvm/test directory. -

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:

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.

- -

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.

Analysis: checks Analysis passes.
Archive: checks the Archive library.
Assembler: checks Assembly reader/writer functionality.
Bitcode: checks Bitcode reader/writer functionality.
CodeGen: checks code generation and each target.
Features: checks various features of the LLVM language.
Linker: tests bitcode linking.
Transforms: tests each of the scalar, IPO, and utility + transforms to ensure they make the right transformations.
Verifier: tests the IR verifier.

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.

+ +

Writing new regression tests

+ +

The regression test structure is very simple, but does require some + information to be set. This information is gathered via configure and + is written to a file, lit.site.cfg + in llvm/test. The llvm/test Makefile does this work for + you.

+ +

In order for the regression tests to work, each directory of tests must + have a lit.local.cfg file. Lit looks for this file to determine how + to run the tests. This file is just Python code and thus is very flexible, + but we've standardized it for the LLVM regression tests. If you're adding a + directory of tests, just copy lit.local.cfg from another directory to + get running. The standard lit.local.cfg simply specifies which files + to look in for tests. Any directory that contains only directories does not + need the lit.local.cfg file. Read the + Lit documentation for more + information.

+ +

The llvm-runtests function looks at each file that is passed to + it and gathers any lines together that match "RUN:". These 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 + llvm-runtests function will issue an error and the test will + fail.

+ +

RUN lines are specified in the comments of the test program using the + keyword RUN followed by a colon, and lastly the command (pipeline) + to execute. Together, these lines form the "script" that + llvm-runtests 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 look like a shell script, they are not. RUN lines are interpreted + directly by the Tcl exec 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.

+ +

lit performs substitution on each RUN line to replace LLVM tool + names with the full paths to the executable built for each tool (in + $(LLVM_OBJ_ROOT)/$(BuildMode)/bin). This ensures that lit does not + invoke any stray LLVM tools in the user's path during testing.

+ +

Each RUN line is executed on its own, distinct from other lines unless + its last character is \. 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 + \ are concatenated until a RUN line that doesn't end in \ is + found. This concatenated set of 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. +

The Programs directory contains all tests which compile and benchmark whole -programs.

Below is an example of legal RUN lines in a .ll file:

+; RUN: llvm-as < %s | llvm-dis > %t1
+; RUN: llvm-dis < %s.bc-13 > %t2
+; RUN: diff %t1 %t2
+

- -

LLVM Test Suite Tree

- +

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 + Tcl exec + command and the + tutorial. + The major differences are:

You can't do 2>&1. That will cause Tcl to write to a + file named &1. Usually this is done to get stderr to go through + a pipe. You can do that in tcl with |& so replace this idiom: + ... 2>&1 | grep with ... |& grep
You can only redirect to a file, not to another descriptor and not from + a here document.
tcl supports redirecting to open files with the @ syntax but you + shouldn't use that here.

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 + quote characters so they will get passed to the invoked program. For + example:

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:

- -

Features -
This directory contains sample codes that test various features of the - LLVM language. These pieces of sample code are run through various - assembler, disassembler, and optimizer passes.
- -
Regression -
This directory contains regression tests for LLVM. 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.
- -
Programs -
The Programs directory 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.
- -
In addition for testing correctness, the Programs 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.
- -
The Programs directory is subdivided into several smaller subdirectories: -
+
+
```
+... | grep 'find this string'
+
```
+
-
- Programs/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.
- Programs/MultiSource -
  The MultiSource directory contains subdirectories which contain - entire programs with multiple source files. Large benchmarks and whole - applications go here.
- Programs/External -
  The External directory contains Makefiles for building code that is - external to (i.e. not distributed with) LLVM. The most prominent member - of this directory is the SPEC 2000 benchmark suite. The presence and - location of these external programs is configured by the LLVM - configure script.

This will fail because the ' characters are passed to grep. This would + instruction grep to look for 'find in the files this and + string'. To avoid this use curly braces to tell Tcl that it should + treat everything enclosed as one value. So our example would become:

QMTest -
This directory contains the QMTest information files. Inside this - directory are QMTest administration files and the Python code that - implements the LLVM test and database classes.
+
+
```
+... | grep {find this string}
+
```
+
-

Additionally, the characters [ and ] 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:

+ +

+... | grep bb[2-8]
+

+ +

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:

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

- -

QMTest Structure

- +

Finally, if you need to pass the \ character down to a program, + then it must be doubled. This is another Tcl special character. So, suppose + you had: -

+... | grep 'i32\*'
+

The LLVM test suite is partially driven by QMTest and partially -driven by GNU Make. Specifically, the Features and Regression tests -are all driven by QMTest. The Programs directory is currently -driven by a set of Makefiles.

This will fail to match what you want (a pointer to i32). First, the + ' do not get stripped off. Second, the \ gets stripped off + by Tcl so what grep sees is: 'i32*'. That's not likely to match + anything. To resolve this you must use \\ and the {}, like + this:

The QMTest system needs to have several pieces of information -available; these pieces of configuration information are known -collectively as the "context" in QMTest parlance. Since the context -for LLVM is relatively large, the master Makefile in llvm/test -sets it for you.

+... | grep {i32\\*}
+

The LLVM database class makes the subdirectories of llvm/test a -QMTest test database. For each directory that contains tests driven by -QMTest, it knows what type of test the source file is and how to run it.

If your system includes GNU grep, make sure +that GREP_OPTIONS is not set in your environment. Otherwise, +you may get invalid results (both false positives and false +negatives).

Hence, the QMTest namespace is essentially what you see in the -Feature and Regression directories, but there is some magic that -the database class performs (as described below).

+ + +

The FileCheck utility

+ + +

+ +

A powerful feature of the RUN: lines is that it allows any arbitrary commands + to be executed as part of the test harness. While standard (portable) unix + tools like 'grep' work fine on run lines, as you see above, there are a lot + of caveats due to interaction with Tcl syntax, and we want to make sure the + run lines are portable to a wide range of systems. Another major problem is + that grep is not very good at checking to verify that the output of a tools + contains a series of different output in a specific order. The FileCheck + tool was designed to help with these problems.

+ +

FileCheck (whose basic command line arguments are described in the FileCheck man page is + designed to read a file to check from standard input, and the set of things + to verify from a file specified as a command line argument. A simple example + of using FileCheck from a RUN line looks like this:

+ +

+; RUN: llvm-as < %s | llc -march=x86-64 | FileCheck %s
+

The QMTest namespace is currently composed of the following tests and test -suites:

This syntax says to pipe the current file ("%s") into llvm-as, pipe that into +llc, then pipe the output of llc into FileCheck. This means that FileCheck will +be verifying its standard input (the llc output) against the filename argument +specified (the original .ll file specified by "%s"). To see how this works, +let's look at the rest of the .ll file (after the RUN line):

Feature -
- These are the feature tests found in the Feature directory. - They are broken up into the following categories: -
-
- ad -
  Assembler/Disassembler tests. These tests verify that a piece of LLVM - assembly language can be assembled into bytecode and then disassembled - into the original assembly language code. It does this several times to - ensure that assembled output can be disassembled and disassembler output - can be assembled. It also verifies that the give assembly language file - can be assembled correctly.
- opt -
  Optimizer tests. These tests verify that two of the optimizer passes - completely optimize a program (i.e. after a single pass, they cannot - optimize a program any further).
- mc -
  Machine code tests. These tests verify that the LLVM assembly - language file can be translated into native assembly code.
- cc -
  C code tests. These tests verify that the specified LLVM assembly - code can be converted into C source code using the C backend.
+
+
```
+define void @sub1(i32* %p, i32 %v) {
+entry:
+; CHECK: sub1:
+; CHECK: subl
+        %0 = tail call i32 @llvm.atomic.load.sub.i32.p0i32(i32* %p, i32 %v)
+        ret void
+}
+
+define void @inc4(i64* %p) {
+entry:
+; CHECK: inc4:
+; CHECK: incq
+        %0 = tail call i64 @llvm.atomic.load.add.i64.p0i64(i64* %p, i64 1)
+        ret void
+}
+
```
+
-
The LLVM database class looks at every file in the Feature directory and - creates a fake test hierarchy containing - Feature.<testtype>.<testname>. So, if you add an LLVM - assembly language file to the Feature directory, it actually creates 5 new - tests: assembler/disassembler, assembler, optimizer, machine code, and C code. -
+
Here you can see some "CHECK:" lines specified in comments. Now you can see +how the file is piped into llvm-as, then llc, and the machine code output is +what we are verifying. FileCheck checks the machine code output to verify that +it matches what the "CHECK:" lines specify.
-
Regression -
These are the regression tests. There is one suite for each - subdirectory of the Regression directory. If you add a new subdirectory - there, you will need to modify, at least, the RegressionMap - variable in QMTest/llvmdb.py so that QMTest knows how to run the - tests in the new subdirectory.
+
The syntax of the CHECK: lines is very simple: they are fixed strings that +must occur in order. FileCheck defaults to ignoring horizontal whitespace +differences (e.g. a space is allowed to match a tab) but otherwise, the contents +of the CHECK: line is required to match some thing in the test file exactly.
-

- +

One nice thing about FileCheck (compared to grep) is that it allows merging +test cases together into logical groups. For example, because the test above +is checking for the "sub1:" and "inc4:" labels, it will not match unless there +is a "subl" in between those labels. If it existed somewhere else in the file, +that would not count: "grep subl" matches if subl exists anywhere in the +file.

+ + +

+ The FileCheck -check-prefix option +

+ +

The FileCheck -check-prefix option allows multiple test configurations to be +driven from one .ll file. This is useful in many circumstances, for example, +testing different architectural variants with llc. Here's a simple example:

+ +

+; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin9 -mattr=sse41 \
+; RUN:              | FileCheck %s -check-prefix=X32
+; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 -mattr=sse41 \
+; RUN:              | FileCheck %s -check-prefix=X64
+
+define <4 x i32> @pinsrd_1(i32 %s, <4 x i32> %tmp) nounwind {
+        %tmp1 = insertelement <4 x i32> %tmp, i32 %s, i32 1
+        ret <4 x i32> %tmp1
+; X32: pinsrd_1:
+; X32:    pinsrd $1, 4(%esp), %xmm0
+
+; X64: pinsrd_1:
+; X64:    pinsrd $1, %edi, %xmm0
+}
+

- -

Programs Structure

- +

In this case, we're testing that we get the expected code generation with +both 32-bit and 64-bit code generation.

As mentioned previously, the Programs tree in llvm/test 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.

+ +

+ The "CHECK-NEXT:" directive +

In addition to the regular Programs tests, the Programs tree 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.

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:

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.

- +

+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
+}
+

- -

Running the LLVM Tests

- +

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 +

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.

The master Makefile in llvm/test is capable of running both the QMTest driven -tests and the Programs tests. By default, it will run all of the tests.

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:

To run only the QMTest driven tests, run gmake qmtest at the -command line in llvm/tests. To run a specific qmtest, suffix the test name with -".t" when running gmake.

+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
+}
+

For example, to run the Regression.LLC tests, type gmake -Regression.LLC.t in llvm/tests.

Note that the Makefiles in llvm/test/Features and llvm/test/Regression are -gone. You must now use QMTest from the llvm/test directory to run them.

+ +

+ FileCheck Pattern Matching Syntax +

To run the Programs test, cd into the llvm/test/Programs directory and type -gmake. Alternatively, you can type gmake TEST=<type> -test to run one of the specialized tests in -llvm/test/Programs/TEST.<type>.Makefile. For example, you could run the -nightly tester tests using the following commands:

+ + +

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:

+ +

- % cd llvm/test/Programs
- % gmake TEST=nightly test
+; CHECK: movhpd	{{[0-9]+}}(%esp), {{%xmm[0-7]}}

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.

In this case, any offset from the ESP register will be allowed, and any xmm +register will be allowed.

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 QMTest, -the result for such tests will be XFAIL (eXpected FAILure). In this way, you -can tell the difference between an expected and unexpected failure.

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.

The Programs tests have no such feature as of 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.

- + + +

+ + +

+ 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:

+ +

+; 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.
$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 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 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 XFAIL: *. Here is an example of an XFAIL line:

+ +

+; 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 testing infrastructure.

+ +

For more information on using LNT to execute the test-suite, please +see the LNT Quickstart +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.

@@ -376,12 +903,12 @@ you separate benign warnings from actual test failures.

+ src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS">

+ src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"> - John T. Criswell
- The LLVM Compiler Infrastructure
+ John T. Criswell, Daniel Dunbar, Reid Spencer, and Tanya Lattner
+ The LLVM Compiler Infrastructure
Last modified: $Date$

+ LLVM Testing Infrastructure Guide +

Overview

Requirements

LLVM testing infrastructure organization

Regression tests

`test-suite`

Debugging Information tests

Quick start

Regression tests

Debugging Information tests

Regression test structure

Writing new regression tests

The FileCheck utility

+ The FileCheck -check-prefix option +

+ The "CHECK-NEXT:" directive +

+ The "CHECK-NOT:" directive +

+ FileCheck Pattern Matching Syntax +

+ FileCheck Variables +

Variables and substitutions

Other Features

`test-suite` Overview

`test-suite` Quickstart

`test-suite` Makefiles