1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
6 <title>LLVM Testing Infrastructure Guide</title>
7 <link rel="stylesheet" href="_static/llvm.css" type="text/css">
12 LLVM Testing Infrastructure Guide
16 <li><a href="#overview">Overview</a></li>
17 <li><a href="#requirements">Requirements</a></li>
18 <li><a href="#org">LLVM testing infrastructure organization</a>
20 <li><a href="#regressiontests">Regression tests</a></li>
21 <li><a href="#testsuite"><tt>test-suite</tt></a></li>
22 <li><a href="#debuginfotests">Debugging Information tests</a></li>
25 <li><a href="#quick">Quick start</a>
27 <li><a href="#quickregressiontests">Regression tests</a></li>
28 <li><a href="#quickdebuginfotests">Debugging Information tests</a></li>
31 <li><a href="#rtstructure">Regression test structure</a>
33 <li><a href="#rtcustom">Writing new regression tests</a></li>
34 <li><a href="#FileCheck">The FileCheck utility</a></li>
35 <li><a href="#rtvars">Variables and substitutions</a></li>
36 <li><a href="#rtfeatures">Other features</a></li>
39 <li><a href="#testsuiteoverview"><tt>test-suite</tt> Overview</a>
41 <li><a href="#testsuitequickstart"><tt>test-suite</tt> Quickstart</a></li>
42 <li><a href="#testsuitemakefiles"><tt>test-suite</tt> Makefiles</a></li>
47 <div class="doc_author">
48 <p>Written by John T. Criswell, Daniel Dunbar, Reid Spencer, and Tanya Lattner</p>
51 <!--=========================================================================-->
52 <h2><a name="overview">Overview</a></h2>
53 <!--=========================================================================-->
57 <p>This document is the reference manual for the LLVM testing infrastructure. It
58 documents the structure of the LLVM testing infrastructure, the tools needed to
59 use it, and how to add and run tests.</p>
63 <!--=========================================================================-->
64 <h2><a name="requirements">Requirements</a></h2>
65 <!--=========================================================================-->
69 <p>In order to use the LLVM testing infrastructure, you will need all of the
70 software required to build LLVM, as well
71 as <a href="http://python.org">Python</a> 2.4 or later.</p>
75 <!--=========================================================================-->
76 <h2><a name="org">LLVM testing infrastructure organization</a></h2>
77 <!--=========================================================================-->
81 <p>The LLVM testing infrastructure contains two major categories of tests:
82 regression tests and whole programs. The regression tests are contained inside
83 the LLVM repository itself under <tt>llvm/test</tt> and are expected to always
84 pass -- they should be run before every commit.</p>
86 <p>The whole programs tests are referred to as the "LLVM test suite" (or
87 "test-suite") and are in the <tt>test-suite</tt> module in subversion. For
88 historical reasons, these tests are also referred to as the "nightly tests" in
89 places, which is less ambiguous than "test-suite" and remains in use although we
90 run them much more often than nightly.</p>
92 <!-- _______________________________________________________________________ -->
93 <h3><a name="regressiontests">Regression tests</a></h3>
94 <!-- _______________________________________________________________________ -->
98 <p>The regression tests are small pieces of code that test a specific feature of
99 LLVM or trigger a specific bug in LLVM. They are usually written in LLVM
100 assembly language, but can be written in other languages if the test targets a
101 particular language front end (and the appropriate <tt>--with-llvmgcc</tt>
102 options were used at <tt>configure</tt> time of the <tt>llvm</tt> module). These
103 tests are driven by the 'lit' testing tool, which is part of LLVM.</p>
105 <p>These code fragments are not complete programs. The code generated
106 from them is never executed to determine correct behavior.</p>
108 <p>These code fragment tests are located in the <tt>llvm/test</tt>
111 <p>Typically when a bug is found in LLVM, a regression test containing
112 just enough code to reproduce the problem should be written and placed
113 somewhere underneath this directory. In most cases, this will be a small
114 piece of LLVM assembly language code, often distilled from an actual
115 application or benchmark.</p>
119 <!-- _______________________________________________________________________ -->
120 <h3><a name="testsuite"><tt>test-suite</tt></a></h3>
121 <!-- _______________________________________________________________________ -->
125 <p>The test suite contains whole programs, which are pieces of code which can be
126 compiled and linked into a stand-alone program that can be executed. These
127 programs are generally written in high level languages such as C or C++.</p>
129 <p>These programs are compiled using a user specified compiler and set of flags,
130 and then executed to capture the program output and timing information. The
131 output of these programs is compared to a reference output to ensure that the
132 program is being compiled correctly.</p>
134 <p>In addition to compiling and executing programs, whole program tests serve as
135 a way of benchmarking LLVM performance, both in terms of the efficiency of the
136 programs generated as well as the speed with which LLVM compiles, optimizes, and
139 <p>The test-suite is located in the <tt>test-suite</tt> Subversion module.</p>
143 <!-- _______________________________________________________________________ -->
144 <h3><a name="debuginfotests">Debugging Information tests</a></h3>
145 <!-- _______________________________________________________________________ -->
149 <p>The test suite contains tests to check quality of debugging information.
150 The test are written in C based languages or in LLVM assembly language. </p>
152 <p>These tests are compiled and run under a debugger. The debugger output
153 is checked to validate of debugging information. See README.txt in the
154 test suite for more information . This test suite is located in the
155 <tt>debuginfo-tests</tt> Subversion module. </p>
161 <!--=========================================================================-->
162 <h2><a name="quick">Quick start</a></h2>
163 <!--=========================================================================-->
167 <p>The tests are located in two separate Subversion modules. The regressions
168 tests are in the main "llvm" module under the directory
169 <tt>llvm/test</tt> (so you get these tests for free with the main llvm
170 tree). Use "make check-all" to run the regression tests after building
173 <p>The more comprehensive test suite that includes whole programs in C and C++
174 is in the <tt>test-suite</tt>
175 module. See <a href="#testsuitequickstart"><tt>test-suite</tt> Quickstart</a>
176 for more information on running these tests.</p>
178 <!-- _______________________________________________________________________ -->
179 <h3><a name="quickregressiontests">Regression tests</a></h3>
181 <!-- _______________________________________________________________________ -->
182 <p>To run all of the LLVM regression tests, use master Makefile in
183 the <tt>llvm/test</tt> directory:</p>
185 <div class="doc_code">
193 <div class="doc_code">
199 <p>If you have <a href="http://clang.llvm.org/">Clang</a> checked out and built,
200 you can run the LLVM and Clang tests simultaneously using:</p>
204 <div class="doc_code">
210 <p>To run the tests with Valgrind (Memcheck by default), just append
211 <tt>VG=1</tt> to the commands above, e.g.:</p>
213 <div class="doc_code">
219 <p>To run individual tests or subsets of tests, you can use the 'llvm-lit'
220 script which is built as part of LLVM. For example, to run the
221 'Integer/BitCast.ll' test by itself you can run:</p>
223 <div class="doc_code">
225 % llvm-lit ~/llvm/test/Integer/BitCast.ll
229 <p>or to run all of the ARM CodeGen tests:</p>
231 <div class="doc_code">
233 % llvm-lit ~/llvm/test/CodeGen/ARM
237 <p>For more information on using the 'lit' tool, see 'llvm-lit --help' or the
242 <!-- _______________________________________________________________________ -->
243 <h3><a name="quickdebuginfotests">Debugging Information tests</a></h3>
245 <!-- _______________________________________________________________________ -->
248 <p> To run debugging information tests simply checkout the tests inside
249 clang/test directory. </p>
251 <div class="doc_code">
254 % svn co http://llvm.org/svn/llvm-project/debuginfo-tests/trunk debuginfo-tests
258 <p> These tests are already set up to run as part of clang regression tests.</p>
266 <!--=========================================================================-->
267 <h2><a name="rtstructure">Regression test structure</a></h2>
268 <!--=========================================================================-->
270 <p>The LLVM regression tests are driven by 'lit' and are located in
271 the <tt>llvm/test</tt> directory.
273 <p>This directory contains a large array of small tests
274 that exercise various features of LLVM and to ensure that regressions do not
275 occur. The directory is broken into several sub-directories, each focused on
276 a particular area of LLVM. A few of the important ones are:</p>
279 <li><tt>Analysis</tt>: checks Analysis passes.</li>
280 <li><tt>Archive</tt>: checks the Archive library.</li>
281 <li><tt>Assembler</tt>: checks Assembly reader/writer functionality.</li>
282 <li><tt>Bitcode</tt>: checks Bitcode reader/writer functionality.</li>
283 <li><tt>CodeGen</tt>: checks code generation and each target.</li>
284 <li><tt>Features</tt>: checks various features of the LLVM language.</li>
285 <li><tt>Linker</tt>: tests bitcode linking.</li>
286 <li><tt>Transforms</tt>: tests each of the scalar, IPO, and utility
287 transforms to ensure they make the right transformations.</li>
288 <li><tt>Verifier</tt>: tests the IR verifier.</li>
291 <!-- _______________________________________________________________________ -->
292 <h3><a name="rtcustom">Writing new regression tests</a></h3>
293 <!-- _______________________________________________________________________ -->
295 <p>The regression test structure is very simple, but does require some
296 information to be set. This information is gathered via <tt>configure</tt> and
297 is written to a file, <tt>lit.site.cfg</tt>
298 in <tt>llvm/test</tt>. The <tt>llvm/test</tt> Makefile does this work for
301 <p>In order for the regression tests to work, each directory of tests must
302 have a <tt>lit.local.cfg</tt> file. Lit looks for this file to determine how
303 to run the tests. This file is just Python code and thus is very flexible,
304 but we've standardized it for the LLVM regression tests. If you're adding a
305 directory of tests, just copy <tt>lit.local.cfg</tt> from another directory to
306 get running. The standard <tt>lit.local.cfg</tt> simply specifies which files
307 to look in for tests. Any directory that contains only directories does not
308 need the <tt>lit.local.cfg</tt> file. Read the
309 <a href="http://llvm.org/cmds/lit.html">Lit documentation</a> for more
312 <p>The <tt>lit</tt> test runner looks at each file that is passed to it and
313 gathers any lines together that match "RUN:". These are the "RUN" lines that
314 specify how the test is to be run. So, each test script must contain RUN lines
315 if it is to do anything. If there are no RUN lines, <tt>lit</tt> function will
316 issue an error and the test will fail.</p>
318 <p>RUN lines are specified in the comments of the test program using the
319 keyword <tt>RUN</tt> followed by a colon, and lastly the command (pipeline)
320 to execute. Together, these lines form the "script" that
321 <tt>lit</tt> executes to run the test case. The syntax of the RUN lines is
322 similar to a shell's syntax for pipelines including I/O redirection and
323 variable substitution. However, even though these lines may <i>look</i> like
324 a shell script, they are not. RUN lines are interpreted directly by the
325 Tcl <tt>exec</tt> command. They are never executed by a shell. Consequently
326 the syntax differs from normal shell script syntax in a few ways. You can
327 specify as many RUN lines as needed.</p>
329 <p>lit performs substitution on each RUN line to replace LLVM tool
330 names with the full paths to the executable built for each tool (in
331 $(LLVM_OBJ_ROOT)/$(BuildMode)/bin). This ensures that lit does not
332 invoke any stray LLVM tools in the user's path during testing.</p>
334 <p>Each RUN line is executed on its own, distinct from other lines unless
335 its last character is <tt>\</tt>. This continuation character causes the RUN
336 line to be concatenated with the next one. In this way you can build up long
337 pipelines of commands without making huge line lengths. The lines ending in
338 <tt>\</tt> are concatenated until a RUN line that doesn't end in <tt>\</tt> is
339 found. This concatenated set of RUN lines then constitutes one execution.
340 Tcl will substitute variables and arrange for the pipeline to be executed. If
341 any process in the pipeline fails, the entire line (and test case) fails too.
344 <p> Below is an example of legal RUN lines in a <tt>.ll</tt> file:</p>
346 <div class="doc_code">
348 ; RUN: llvm-as < %s | llvm-dis > %t1
349 ; RUN: llvm-dis < %s.bc-13 > %t2
354 <p>As with a Unix shell, the RUN: lines permit pipelines and I/O redirection
355 to be used. However, the usage is slightly different than for Bash. To check
356 what's legal, see the documentation for the
357 <a href="http://www.tcl.tk/man/tcl8.5/TclCmd/exec.htm#M2">Tcl exec</a>
359 <a href="http://www.tcl.tk/man/tcl8.5/tutorial/Tcl26.html">tutorial</a>.
360 The major differences are:</p>
362 <li>You can't do <tt>2>&1</tt>. That will cause Tcl to write to a
363 file named <tt>&1</tt>. Usually this is done to get stderr to go through
364 a pipe. You can do that in tcl with <tt>|&</tt> so replace this idiom:
365 <tt>... 2>&1 | grep</tt> with <tt>... |& grep</tt></li>
366 <li>You can only redirect to a file, not to another descriptor and not from
367 a here document.</li>
368 <li>tcl supports redirecting to open files with the @ syntax but you
369 shouldn't use that here.</li>
372 <p>There are some quoting rules that you must pay attention to when writing
373 your RUN lines. In general nothing needs to be quoted. Tcl won't strip off any
374 quote characters so they will get passed to the invoked program. For
377 <div class="doc_code">
379 ... | grep 'find this string'
383 <p>This will fail because the ' characters are passed to grep. This would
384 instruction grep to look for <tt>'find</tt> in the files <tt>this</tt> and
385 <tt>string'</tt>. To avoid this use curly braces to tell Tcl that it should
386 treat everything enclosed as one value. So our example would become:</p>
388 <div class="doc_code">
390 ... | grep {find this string}
394 <p>Additionally, the characters <tt>[</tt> and <tt>]</tt> are treated
395 specially by Tcl. They tell Tcl to interpret the content as a command to
396 execute. Since these characters are often used in regular expressions this can
397 have disastrous results and cause the entire test run in a directory to fail.
398 For example, a common idiom is to look for some basicblock number:</p>
400 <div class="doc_code">
406 <p>This, however, will cause Tcl to fail because its going to try to execute
407 a program named "2-8". Instead, what you want is this:</p>
409 <div class="doc_code">
411 ... | grep {bb\[2-8\]}
415 <p>Finally, if you need to pass the <tt>\</tt> character down to a program,
416 then it must be doubled. This is another Tcl special character. So, suppose
419 <div class="doc_code">
425 <p>This will fail to match what you want (a pointer to i32). First, the
426 <tt>'</tt> do not get stripped off. Second, the <tt>\</tt> gets stripped off
427 by Tcl so what grep sees is: <tt>'i32*'</tt>. That's not likely to match
428 anything. To resolve this you must use <tt>\\</tt> and the <tt>{}</tt>, like
431 <div class="doc_code">
437 <p>If your system includes GNU <tt>grep</tt>, make sure
438 that <tt>GREP_OPTIONS</tt> is not set in your environment. Otherwise,
439 you may get invalid results (both false positives and false
444 <!-- _______________________________________________________________________ -->
445 <h3><a name="FileCheck">The FileCheck utility</a></h3>
446 <!-- _______________________________________________________________________ -->
450 <p>A powerful feature of the RUN: lines is that it allows any arbitrary commands
451 to be executed as part of the test harness. While standard (portable) unix
452 tools like 'grep' work fine on run lines, as you see above, there are a lot
453 of caveats due to interaction with Tcl syntax, and we want to make sure the
454 run lines are portable to a wide range of systems. Another major problem is
455 that grep is not very good at checking to verify that the output of a tools
456 contains a series of different output in a specific order. The FileCheck
457 tool was designed to help with these problems.</p>
459 <p>FileCheck (whose basic command line arguments are described in <a
460 href="http://llvm.org/cmds/FileCheck.html">the FileCheck man page</a> is
461 designed to read a file to check from standard input, and the set of things
462 to verify from a file specified as a command line argument. A simple example
463 of using FileCheck from a RUN line looks like this:</p>
465 <div class="doc_code">
467 ; RUN: llvm-as < %s | llc -march=x86-64 | <b>FileCheck %s</b>
471 <p>This syntax says to pipe the current file ("%s") into llvm-as, pipe that into
472 llc, then pipe the output of llc into FileCheck. This means that FileCheck will
473 be verifying its standard input (the llc output) against the filename argument
474 specified (the original .ll file specified by "%s"). To see how this works,
475 let's look at the rest of the .ll file (after the RUN line):</p>
477 <div class="doc_code">
479 define void @sub1(i32* %p, i32 %v) {
481 ; <b>CHECK: sub1:</b>
483 %0 = tail call i32 @llvm.atomic.load.sub.i32.p0i32(i32* %p, i32 %v)
487 define void @inc4(i64* %p) {
489 ; <b>CHECK: inc4:</b>
491 %0 = tail call i64 @llvm.atomic.load.add.i64.p0i64(i64* %p, i64 1)
497 <p>Here you can see some "CHECK:" lines specified in comments. Now you can see
498 how the file is piped into llvm-as, then llc, and the machine code output is
499 what we are verifying. FileCheck checks the machine code output to verify that
500 it matches what the "CHECK:" lines specify.</p>
502 <p>The syntax of the CHECK: lines is very simple: they are fixed strings that
503 must occur in order. FileCheck defaults to ignoring horizontal whitespace
504 differences (e.g. a space is allowed to match a tab) but otherwise, the contents
505 of the CHECK: line is required to match some thing in the test file exactly.</p>
507 <p>One nice thing about FileCheck (compared to grep) is that it allows merging
508 test cases together into logical groups. For example, because the test above
509 is checking for the "sub1:" and "inc4:" labels, it will not match unless there
510 is a "subl" in between those labels. If it existed somewhere else in the file,
511 that would not count: "grep subl" matches if subl exists anywhere in the
514 <!-- _______________________________________________________________________ -->
516 <a name="FileCheck-check-prefix">The FileCheck -check-prefix option</a>
521 <p>The FileCheck -check-prefix option allows multiple test configurations to be
522 driven from one .ll file. This is useful in many circumstances, for example,
523 testing different architectural variants with llc. Here's a simple example:</p>
525 <div class="doc_code">
527 ; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin9 -mattr=sse41 \
528 ; RUN: | <b>FileCheck %s -check-prefix=X32</b>
529 ; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 -mattr=sse41 \
530 ; RUN: | <b>FileCheck %s -check-prefix=X64</b>
532 define <4 x i32> @pinsrd_1(i32 %s, <4 x i32> %tmp) nounwind {
533 %tmp1 = insertelement <4 x i32> %tmp, i32 %s, i32 1
534 ret <4 x i32> %tmp1
535 ; <b>X32:</b> pinsrd_1:
536 ; <b>X32:</b> pinsrd $1, 4(%esp), %xmm0
538 ; <b>X64:</b> pinsrd_1:
539 ; <b>X64:</b> pinsrd $1, %edi, %xmm0
544 <p>In this case, we're testing that we get the expected code generation with
545 both 32-bit and 64-bit code generation.</p>
549 <!-- _______________________________________________________________________ -->
551 <a name="FileCheck-CHECK-NEXT">The "CHECK-NEXT:" directive</a>
556 <p>Sometimes you want to match lines and would like to verify that matches
557 happen on exactly consecutive lines with no other lines in between them. In
558 this case, you can use CHECK: and CHECK-NEXT: directives to specify this. If
559 you specified a custom check prefix, just use "<PREFIX>-NEXT:". For
560 example, something like this works as you'd expect:</p>
562 <div class="doc_code">
564 define void @t2(<2 x double>* %r, <2 x double>* %A, double %B) {
565 %tmp3 = load <2 x double>* %A, align 16
566 %tmp7 = insertelement <2 x double> undef, double %B, i32 0
567 %tmp9 = shufflevector <2 x double> %tmp3,
568 <2 x double> %tmp7,
569 <2 x i32> < i32 0, i32 2 >
570 store <2 x double> %tmp9, <2 x double>* %r, align 16
574 ; <b>CHECK:</b> movl 8(%esp), %eax
575 ; <b>CHECK-NEXT:</b> movapd (%eax), %xmm0
576 ; <b>CHECK-NEXT:</b> movhpd 12(%esp), %xmm0
577 ; <b>CHECK-NEXT:</b> movl 4(%esp), %eax
578 ; <b>CHECK-NEXT:</b> movapd %xmm0, (%eax)
579 ; <b>CHECK-NEXT:</b> ret
584 <p>CHECK-NEXT: directives reject the input unless there is exactly one newline
585 between it an the previous directive. A CHECK-NEXT cannot be the first
586 directive in a file.</p>
590 <!-- _______________________________________________________________________ -->
592 <a name="FileCheck-CHECK-NOT">The "CHECK-NOT:" directive</a>
597 <p>The CHECK-NOT: directive is used to verify that a string doesn't occur
598 between two matches (or the first match and the beginning of the file). For
599 example, to verify that a load is removed by a transformation, a test like this
602 <div class="doc_code">
604 define i8 @coerce_offset0(i32 %V, i32* %P) {
605 store i32 %V, i32* %P
607 %P2 = bitcast i32* %P to i8*
608 %P3 = getelementptr i8* %P2, i32 2
612 ; <b>CHECK:</b> @coerce_offset0
613 ; <b>CHECK-NOT:</b> load
614 ; <b>CHECK:</b> ret i8
621 <!-- _______________________________________________________________________ -->
623 <a name="FileCheck-Matching">FileCheck Pattern Matching Syntax</a>
630 <p>The CHECK: and CHECK-NOT: directives both take a pattern to match. For most
631 uses of FileCheck, fixed string matching is perfectly sufficient. For some
632 things, a more flexible form of matching is desired. To support this, FileCheck
633 allows you to specify regular expressions in matching strings, surrounded by
634 double braces: <b>{{yourregex}}</b>. Because we want to use fixed string
635 matching for a majority of what we do, FileCheck has been designed to support
636 mixing and matching fixed string matching with regular expressions. This allows
637 you to write things like this:</p>
639 <div class="doc_code">
641 ; CHECK: movhpd <b>{{[0-9]+}}</b>(%esp), <b>{{%xmm[0-7]}}</b>
645 <p>In this case, any offset from the ESP register will be allowed, and any xmm
646 register will be allowed.</p>
648 <p>Because regular expressions are enclosed with double braces, they are
649 visually distinct, and you don't need to use escape characters within the double
650 braces like you would in C. In the rare case that you want to match double
651 braces explicitly from the input, you can use something ugly like
652 <b>{{[{][{]}}</b> as your pattern.</p>
654 <!-- {% endraw %} -->
658 <!-- _______________________________________________________________________ -->
660 <a name="FileCheck-Variables">FileCheck Variables</a>
668 <p>It is often useful to match a pattern and then verify that it occurs again
669 later in the file. For codegen tests, this can be useful to allow any register,
670 but verify that that register is used consistently later. To do this, FileCheck
671 allows named variables to be defined and substituted into patterns. Here is a
674 <div class="doc_code">
677 ; CHECK: notw <b>[[REGISTER:%[a-z]+]]</b>
678 ; CHECK: andw {{.*}}<b>[[REGISTER]]</b>
682 <p>The first check line matches a regex (<tt>%[a-z]+</tt>) and captures it into
683 the variables "REGISTER". The second line verifies that whatever is in REGISTER
684 occurs later in the file after an "andw". FileCheck variable references are
685 always contained in <tt>[[ ]]</tt> pairs, are named, and their names can be
686 formed with the regex "<tt>[a-zA-Z][a-zA-Z0-9]*</tt>". If a colon follows the
687 name, then it is a definition of the variable, if not, it is a use.</p>
689 <p>FileCheck variables can be defined multiple times, and uses always get the
690 latest value. Note that variables are all read at the start of a "CHECK" line
691 and are all defined at the end. This means that if you have something like
692 "<tt>CHECK: [[XYZ:.*]]x[[XYZ]]</tt>" that the check line will read the previous
693 value of the XYZ variable and define a new one after the match is performed. If
694 you need to do something like this you can probably take advantage of the fact
695 that FileCheck is not actually line-oriented when it matches, this allows you to
696 define two separate CHECK lines that match on the same line.
699 <!-- {% endraw %} -->
705 <!-- _______________________________________________________________________ -->
706 <h3><a name="rtvars">Variables and substitutions</a></h3>
707 <!-- _______________________________________________________________________ -->
709 <p>With a RUN line there are a number of substitutions that are permitted. In
710 general, any Tcl variable that is available in the <tt>substitute</tt>
711 function (in <tt>test/lib/llvm.exp</tt>) can be substituted into a RUN line.
712 To make a substitution just write the variable's name preceded by a $.
713 Additionally, for compatibility reasons with previous versions of the test
714 library, certain names can be accessed with an alternate syntax: a % prefix.
715 These alternates are deprecated and may go away in a future version.
717 <p>Here are the available variable names. The alternate syntax is listed in
720 <dl style="margin-left: 25px">
721 <dt><b>$test</b> (%s)</dt>
722 <dd>The full path to the test case's source. This is suitable for passing
723 on the command line as the input to an llvm tool.</dd>
725 <dt><b>$srcdir</b></dt>
726 <dd>The source directory from where the "<tt>make check</tt>" was run.</dd>
728 <dt><b>objdir</b></dt>
729 <dd>The object directory that corresponds to the <tt>$srcdir</tt>.</dd>
731 <dt><b>subdir</b></dt>
732 <dd>A partial path from the <tt>test</tt> directory that contains the
733 sub-directory that contains the test source being executed.</dd>
735 <dt><b>srcroot</b></dt>
736 <dd>The root directory of the LLVM src tree.</dd>
738 <dt><b>objroot</b></dt>
739 <dd>The root directory of the LLVM object tree. This could be the same
743 <dd>The path to the directory that contains the test case source. This is
744 for locating any supporting files that are not generated by the test, but
745 used by the test.</dd>
748 <dd>The path to a temporary file name that could be used for this test case.
749 The file name won't conflict with other test cases. You can append to it if
750 you need multiple temporaries. This is useful as the destination of some
751 redirected output.</dd>
753 <dt><b>target_triplet</b> (%target_triplet)</dt>
754 <dd>The target triplet that corresponds to the current host machine (the one
755 running the test cases). This should probably be called "host".<dd>
757 <dt><b>link</b> (%link)</dt>
758 <dd>This full link command used to link LLVM executables. This has all the
759 configured -I, -L and -l options.</dd>
761 <dt><b>shlibext</b> (%shlibext)</dt>
762 <dd>The suffix for the host platforms share library (dll) files. This
763 includes the period as the first character.</dd>
765 <p>To add more variables, two things need to be changed. First, add a line in
766 the <tt>test/Makefile</tt> that creates the <tt>site.exp</tt> file. This will
767 "set" the variable as a global in the site.exp file. Second, in the
768 <tt>test/lib/llvm.exp</tt> file, in the substitute proc, add the variable name
769 to the list of "global" declarations at the beginning of the proc. That's it,
770 the variable can then be used in test scripts.</p>
773 <!-- _______________________________________________________________________ -->
774 <h3><a name="rtfeatures">Other Features</a></h3>
775 <!-- _______________________________________________________________________ -->
777 <p>To make RUN line writing easier, there are several shell scripts located
778 in the <tt>llvm/test/Scripts</tt> directory. This directory is in the PATH
779 when running tests, so you can just call these scripts using their name. For
782 <dt><b>ignore</b></dt>
783 <dd>This script runs its arguments and then always returns 0. This is useful
784 in cases where the test needs to cause a tool to generate an error (e.g. to
785 check the error output). However, any program in a pipeline that returns a
786 non-zero result will cause the test to fail. This script overcomes that
787 issue and nicely documents that the test case is purposefully ignoring the
788 result code of the tool</dd>
791 <dd>This script runs its arguments and then inverts the result code from
792 it. Zero result codes become 1. Non-zero result codes become 0. This is
793 useful to invert the result of a grep. For example "not grep X" means
794 succeed only if you don't find X in the input.</dd>
797 <p>Sometimes it is necessary to mark a test case as "expected fail" or XFAIL.
798 You can easily mark a test as XFAIL just by including <tt>XFAIL: </tt> on a
799 line near the top of the file. This signals that the test case should succeed
800 if the test fails. Such test cases are counted separately by the testing tool. To
801 specify an expected fail, use the XFAIL keyword in the comments of the test
802 program followed by a colon and one or more regular expressions (separated by
803 a comma). The regular expressions allow you to XFAIL the test conditionally by
804 host platform. The regular expressions following the : are matched against the
805 target triplet for the host machine. If there is a match, the test is expected
806 to fail. If not, the test is expected to succeed. To XFAIL everywhere just
807 specify <tt>XFAIL: *</tt>. Here is an example of an <tt>XFAIL</tt> line:</p>
809 <div class="doc_code">
815 <p>Finally, any line that contains "END." will cause the special
816 interpretation of lines to terminate. This is generally done right after the
817 last RUN: line. This has two side effects: (a) it prevents special
818 interpretation of lines that are part of the test program, not the
819 instructions to the test case, and (b) it speeds things up for really big test
820 cases by avoiding interpretation of the remainder of the file.</p>
826 <!--=========================================================================-->
827 <h2><a name="testsuiteoverview"><tt>test-suite</tt> Overview</a></h2>
828 <!--=========================================================================-->
832 <p>The <tt>test-suite</tt> module contains a number of programs that can be
833 compiled and executed. The <tt>test-suite</tt> includes reference outputs for
834 all of the programs, so that the output of the executed program can be checked
837 <p><tt>test-suite</tt> tests are divided into three types of tests: MultiSource,
838 SingleSource, and External.</p>
841 <li><tt>test-suite/SingleSource</tt>
842 <p>The SingleSource directory contains test programs that are only a single
843 source file in size. These are usually small benchmark programs or small
844 programs that calculate a particular value. Several such programs are grouped
845 together in each directory.</p></li>
847 <li><tt>test-suite/MultiSource</tt>
848 <p>The MultiSource directory contains subdirectories which contain entire
849 programs with multiple source files. Large benchmarks and whole applications
852 <li><tt>test-suite/External</tt>
853 <p>The External directory contains Makefiles for building code that is external
854 to (i.e., not distributed with) LLVM. The most prominent members of this
855 directory are the SPEC 95 and SPEC 2000 benchmark suites. The <tt>External</tt>
856 directory does not contain these actual tests, but only the Makefiles that know
857 how to properly compile these programs from somewhere else. When
858 using <tt>LNT</tt>, use the <tt>--test-externals</tt> option to include these
859 tests in the results.</p></li>
863 <!--=========================================================================-->
864 <h2><a name="testsuitequickstart"><tt>test-suite</tt> Quickstart</a></h2>
865 <!--=========================================================================-->
868 <p>The modern way of running the <tt>test-suite</tt> is focused on testing and
869 benchmarking complete compilers using
870 the <a href="http://llvm.org/docs/lnt">LNT</a> testing infrastructure.</p>
872 <p>For more information on using LNT to execute the <tt>test-suite</tt>, please
873 see the <a href="http://llvm.org/docs/lnt/quickstart.html">LNT Quickstart</a>
877 <!--=========================================================================-->
878 <h2><a name="testsuitemakefiles"><tt>test-suite</tt> Makefiles</a></h2>
879 <!--=========================================================================-->
882 <p>Historically, the <tt>test-suite</tt> was executed using a complicated setup
883 of Makefiles. The LNT based approach above is recommended for most users, but
884 there are some testing scenarios which are not supported by the LNT approach. In
885 addition, LNT currently uses the Makefile setup under the covers and so
886 developers who are interested in how LNT works under the hood may want to
887 understand the Makefile based setup.</p>
889 <p>For more information on the <tt>test-suite</tt> Makefile setup, please see
890 the <a href="TestSuiteMakefileGuide.html">Test Suite Makefile Guide.</a></p>
893 <!-- *********************************************************************** -->
897 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
898 src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
899 <a href="http://validator.w3.org/check/referer"><img
900 src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
902 John T. Criswell, Daniel Dunbar, Reid Spencer, and Tanya Lattner<br>
903 <a href="http://llvm.org/">The LLVM Compiler Infrastructure</a><br>
904 Last modified: $Date$