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11 LLVM Testing Infrastructure Guide
15 <li><a href="#overview">Overview</a></li>
16 <li><a href="#requirements">Requirements</a></li>
17 <li><a href="#org">LLVM testing infrastructure organization</a>
19 <li><a href="#regressiontests">Regression tests</a></li>
20 <li><a href="#testsuite">Test suite</a></li>
21 <li><a href="#debuginfotests">Debugging Information tests</a></li>
24 <li><a href="#quick">Quick start</a>
26 <li><a href="#quickregressiontests">Regression tests</a></li>
27 <li><a href="#quicktestsuite">Test suite</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="#testsuitestructure">Test suite structure</a></li>
40 <li><a href="#testsuiterun">Running the test suite</a>
42 <li><a href="#testsuiteexternal">Configuring External Tests</a></li>
43 <li><a href="#testsuitetests">Running different tests</a></li>
44 <li><a href="#testsuiteoutput">Generating test output</a></li>
45 <li><a href="#testsuitecustom">Writing custom tests for test-suite</a></li>
50 <div class="doc_author">
51 <p>Written by John T. Criswell, Daniel Dunbar, Reid Spencer, and Tanya Lattner</p>
54 <!--=========================================================================-->
55 <h2><a name="overview">Overview</a></h2>
56 <!--=========================================================================-->
60 <p>This document is the reference manual for the LLVM testing infrastructure. It
61 documents the structure of the LLVM testing infrastructure, the tools needed to
62 use it, and how to add and run tests.</p>
66 <!--=========================================================================-->
67 <h2><a name="requirements">Requirements</a></h2>
68 <!--=========================================================================-->
72 <p>In order to use the LLVM testing infrastructure, you will need all of the
73 software required to build LLVM, as well
74 as <a href="http://python.org">Python</a> 2.4 or later.</p>
78 <!--=========================================================================-->
79 <h2><a name="org">LLVM testing infrastructure organization</a></h2>
80 <!--=========================================================================-->
84 <p>The LLVM testing infrastructure contains two major categories of tests:
85 regression tests and whole programs. The regression tests are contained inside
86 the LLVM repository itself under <tt>llvm/test</tt> and are expected to always
87 pass -- they should be run before every commit. The whole programs tests are
88 referred to as the "LLVM test suite" and are in the <tt>test-suite</tt> module
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">Test suite</a></h3>
121 <!-- _______________________________________________________________________ -->
125 <p>The test suite contains whole programs, which are pieces of
126 code which can be compiled and linked into a stand-alone program that can be
127 executed. These programs are generally written in high level languages such as
128 C or C++, but sometimes they are written straight in LLVM assembly.</p>
130 <p>These programs are compiled and then executed using several different
131 methods (native compiler, LLVM C backend, LLVM JIT, LLVM native code generation,
132 etc). The output of these programs is compared to ensure that LLVM is compiling
133 the program correctly.</p>
135 <p>In addition to compiling and executing programs, whole program tests serve as
136 a way of benchmarking LLVM performance, both in terms of the efficiency of the
137 programs generated as well as the speed with which LLVM compiles, optimizes, and
140 <p>The test-suite is located in the <tt>test-suite</tt> Subversion module.</p>
144 <!-- _______________________________________________________________________ -->
145 <h3><a name="debuginfotests">Debugging Information tests</a></h3>
146 <!-- _______________________________________________________________________ -->
150 <p>The test suite contains tests to check quality of debugging information.
151 The test are written in C based languages or in LLVM assembly language. </p>
153 <p>These tests are compiled and run under a debugger. The debugger output
154 is checked to validate of debugging information. See README.txt in the
155 test suite for more information . This test suite is located in the
156 <tt>debuginfo-tests</tt> Subversion module. </p>
162 <!--=========================================================================-->
163 <h2><a name="quick">Quick start</a></h2>
164 <!--=========================================================================-->
168 <p>The tests are located in two separate Subversion modules. The regressions
169 tests are in the main "llvm" module under the directory
170 <tt>llvm/test</tt> (so you get these tests for free with the main llvm tree).
171 The more comprehensive test suite that includes whole
172 programs in C and C++ is in the <tt>test-suite</tt> module. This module should
173 be checked out to the <tt>llvm/projects</tt> directory (don't use another name
174 than the default "test-suite", for then the test suite will be run every time
175 you run <tt>make</tt> in the main <tt>llvm</tt> directory).
176 When you <tt>configure</tt> the <tt>llvm</tt> module,
177 the <tt>test-suite</tt> directory will be automatically configured.
178 Alternatively, you can configure the <tt>test-suite</tt> module manually.</p>
180 <!-- _______________________________________________________________________ -->
181 <h3><a name="quickregressiontests">Regression tests</a></h3>
183 <!-- _______________________________________________________________________ -->
184 <p>To run all of the LLVM regression tests, use master Makefile in
185 the <tt>llvm/test</tt> directory:</p>
187 <div class="doc_code">
195 <div class="doc_code">
201 <p>If you have <a href="http://clang.llvm.org/">Clang</a> checked out and built,
202 you can run the LLVM and Clang tests simultaneously using:</p>
206 <div class="doc_code">
212 <p>To run the tests with Valgrind (Memcheck by default), just append
213 <tt>VG=1</tt> to the commands above, e.g.:</p>
215 <div class="doc_code">
221 <p>To run individual tests or subsets of tests, you can use the 'llvm-lit'
222 script which is built as part of LLVM. For example, to run the
223 'Integer/BitCast.ll' test by itself you can run:</p>
225 <div class="doc_code">
227 % llvm-lit ~/llvm/test/Integer/BitCast.ll
231 <p>or to run all of the ARM CodeGen tests:</p>
233 <div class="doc_code">
235 % llvm-lit ~/llvm/test/CodeGen/ARM
239 <p>For more information on using the 'lit' tool, see 'llvm-lit --help' or the
244 <!-- _______________________________________________________________________ -->
245 <h3><a name="quicktestsuite">Test suite</a></h3>
246 <!-- _______________________________________________________________________ -->
250 <p>To run the comprehensive test suite (tests that compile and execute whole
251 programs), first checkout and setup the <tt>test-suite</tt> module:</p>
253 <div class="doc_code">
256 % svn co http://llvm.org/svn/llvm-project/test-suite/trunk test-suite
258 % ./configure --with-llvmgccdir=$LLVM_GCC_DIR
262 <p>where <tt>$LLVM_GCC_DIR</tt> is the directory where
263 you <em>installed</em> llvm-gcc, not its src or obj
264 dir. The <tt>--with-llvmgccdir</tt> option assumes that
265 the <tt>llvm-gcc-4.2</tt> module was configured with
266 <tt>--program-prefix=llvm-</tt>, and therefore that the C and C++
267 compiler drivers are called <tt>llvm-gcc</tt> and <tt>llvm-g++</tt>
268 respectively. If this is not the case,
269 use <tt>--with-llvmgcc</tt>/<tt>--with-llvmgxx</tt> to specify each
270 executable's location.</p>
272 <p>Then, run the entire test suite by running make in the <tt>test-suite</tt>
275 <div class="doc_code">
277 % cd projects/test-suite
282 <p>Usually, running the "nightly" set of tests is a good idea, and you can also
283 let it generate a report by running:</p>
285 <div class="doc_code">
287 % cd projects/test-suite
288 % gmake TEST=nightly report report.html
292 <p>Any of the above commands can also be run in a subdirectory of
293 <tt>projects/test-suite</tt> to run the specified test only on the programs in
294 that subdirectory.</p>
298 <!-- _______________________________________________________________________ -->
299 <h3><a name="quickdebuginfotests">Debugging Information tests</a></h3>
301 <!-- _______________________________________________________________________ -->
304 <p> To run debugging information tests simply checkout the tests inside
305 clang/test directory. </p>
307 <div class="doc_code">
310 % svn co http://llvm.org/svn/llvm-project/debuginfo-tests/trunk debuginfo-tests
314 <p> These tests are already set up to run as part of clang regression tests.</p>
322 <!--=========================================================================-->
323 <h2><a name="rtstructure">Regression test structure</a></h2>
324 <!--=========================================================================-->
326 <p>The LLVM regression tests are driven by 'lit' and are located in
327 the <tt>llvm/test</tt> directory.
329 <p>This directory contains a large array of small tests
330 that exercise various features of LLVM and to ensure that regressions do not
331 occur. The directory is broken into several sub-directories, each focused on
332 a particular area of LLVM. A few of the important ones are:</p>
335 <li><tt>Analysis</tt>: checks Analysis passes.</li>
336 <li><tt>Archive</tt>: checks the Archive library.</li>
337 <li><tt>Assembler</tt>: checks Assembly reader/writer functionality.</li>
338 <li><tt>Bitcode</tt>: checks Bitcode reader/writer functionality.</li>
339 <li><tt>CodeGen</tt>: checks code generation and each target.</li>
340 <li><tt>Features</tt>: checks various features of the LLVM language.</li>
341 <li><tt>Linker</tt>: tests bitcode linking.</li>
342 <li><tt>Transforms</tt>: tests each of the scalar, IPO, and utility
343 transforms to ensure they make the right transformations.</li>
344 <li><tt>Verifier</tt>: tests the IR verifier.</li>
347 <!-- _______________________________________________________________________ -->
348 <h3><a name="rtcustom">Writing new regression tests</a></h3>
349 <!-- _______________________________________________________________________ -->
351 <p>The regression test structure is very simple, but does require some
352 information to be set. This information is gathered via <tt>configure</tt> and
353 is written to a file, <tt>lit.site.cfg</tt>
354 in <tt>llvm/test</tt>. The <tt>llvm/test</tt> Makefile does this work for
357 <p>In order for the regression tests to work, each directory of tests must
358 have a <tt>dg.exp</tt> file. Lit looks for this file to determine how to
359 run the tests. This file is just a Tcl script and it can do anything you want,
360 but we've standardized it for the LLVM regression tests. If you're adding a
361 directory of tests, just copy <tt>dg.exp</tt> from another directory to get
362 running. The standard <tt>dg.exp</tt> simply loads a Tcl library
363 (<tt>test/lib/llvm.exp</tt>) and calls the <tt>llvm_runtests</tt> function
364 defined in that library with a list of file names to run. The names are
365 obtained by using Tcl's glob command. Any directory that contains only
366 directories does not need the <tt>dg.exp</tt> file.</p>
368 <p>The <tt>llvm-runtests</tt> function looks at each file that is passed to
369 it and gathers any lines together that match "RUN:". These are the "RUN" lines
370 that specify how the test is to be run. So, each test script must contain
371 RUN lines if it is to do anything. If there are no RUN lines, the
372 <tt>llvm-runtests</tt> function will issue an error and the test will
375 <p>RUN lines are specified in the comments of the test program using the
376 keyword <tt>RUN</tt> followed by a colon, and lastly the command (pipeline)
377 to execute. Together, these lines form the "script" that
378 <tt>llvm-runtests</tt> executes to run the test case. The syntax of the
379 RUN lines is similar to a shell's syntax for pipelines including I/O
380 redirection and variable substitution. However, even though these lines
381 may <i>look</i> like a shell script, they are not. RUN lines are interpreted
382 directly by the Tcl <tt>exec</tt> command. They are never executed by a
383 shell. Consequently the syntax differs from normal shell script syntax in a
384 few ways. You can specify as many RUN lines as needed.</p>
386 <p>lit performs substitution on each RUN line to replace LLVM tool
387 names with the full paths to the executable built for each tool (in
388 $(LLVM_OBJ_ROOT)/$(BuildMode)/bin). This ensures that lit does not
389 invoke any stray LLVM tools in the user's path during testing.</p>
391 <p>Each RUN line is executed on its own, distinct from other lines unless
392 its last character is <tt>\</tt>. This continuation character causes the RUN
393 line to be concatenated with the next one. In this way you can build up long
394 pipelines of commands without making huge line lengths. The lines ending in
395 <tt>\</tt> are concatenated until a RUN line that doesn't end in <tt>\</tt> is
396 found. This concatenated set of RUN lines then constitutes one execution.
397 Tcl will substitute variables and arrange for the pipeline to be executed. If
398 any process in the pipeline fails, the entire line (and test case) fails too.
401 <p> Below is an example of legal RUN lines in a <tt>.ll</tt> file:</p>
403 <div class="doc_code">
405 ; RUN: llvm-as < %s | llvm-dis > %t1
406 ; RUN: llvm-dis < %s.bc-13 > %t2
411 <p>As with a Unix shell, the RUN: lines permit pipelines and I/O redirection
412 to be used. However, the usage is slightly different than for Bash. To check
413 what's legal, see the documentation for the
414 <a href="http://www.tcl.tk/man/tcl8.5/TclCmd/exec.htm#M2">Tcl exec</a>
416 <a href="http://www.tcl.tk/man/tcl8.5/tutorial/Tcl26.html">tutorial</a>.
417 The major differences are:</p>
419 <li>You can't do <tt>2>&1</tt>. That will cause Tcl to write to a
420 file named <tt>&1</tt>. Usually this is done to get stderr to go through
421 a pipe. You can do that in tcl with <tt>|&</tt> so replace this idiom:
422 <tt>... 2>&1 | grep</tt> with <tt>... |& grep</tt></li>
423 <li>You can only redirect to a file, not to another descriptor and not from
424 a here document.</li>
425 <li>tcl supports redirecting to open files with the @ syntax but you
426 shouldn't use that here.</li>
429 <p>There are some quoting rules that you must pay attention to when writing
430 your RUN lines. In general nothing needs to be quoted. Tcl won't strip off any
431 quote characters so they will get passed to the invoked program. For
434 <div class="doc_code">
436 ... | grep 'find this string'
440 <p>This will fail because the ' characters are passed to grep. This would
441 instruction grep to look for <tt>'find</tt> in the files <tt>this</tt> and
442 <tt>string'</tt>. To avoid this use curly braces to tell Tcl that it should
443 treat everything enclosed as one value. So our example would become:</p>
445 <div class="doc_code">
447 ... | grep {find this string}
451 <p>Additionally, the characters <tt>[</tt> and <tt>]</tt> are treated
452 specially by Tcl. They tell Tcl to interpret the content as a command to
453 execute. Since these characters are often used in regular expressions this can
454 have disastrous results and cause the entire test run in a directory to fail.
455 For example, a common idiom is to look for some basicblock number:</p>
457 <div class="doc_code">
463 <p>This, however, will cause Tcl to fail because its going to try to execute
464 a program named "2-8". Instead, what you want is this:</p>
466 <div class="doc_code">
468 ... | grep {bb\[2-8\]}
472 <p>Finally, if you need to pass the <tt>\</tt> character down to a program,
473 then it must be doubled. This is another Tcl special character. So, suppose
476 <div class="doc_code">
482 <p>This will fail to match what you want (a pointer to i32). First, the
483 <tt>'</tt> do not get stripped off. Second, the <tt>\</tt> gets stripped off
484 by Tcl so what grep sees is: <tt>'i32*'</tt>. That's not likely to match
485 anything. To resolve this you must use <tt>\\</tt> and the <tt>{}</tt>, like
488 <div class="doc_code">
494 <p>If your system includes GNU <tt>grep</tt>, make sure
495 that <tt>GREP_OPTIONS</tt> is not set in your environment. Otherwise,
496 you may get invalid results (both false positives and false
501 <!-- _______________________________________________________________________ -->
502 <h3><a name="FileCheck">The FileCheck utility</a></h3>
503 <!-- _______________________________________________________________________ -->
507 <p>A powerful feature of the RUN: lines is that it allows any arbitrary commands
508 to be executed as part of the test harness. While standard (portable) unix
509 tools like 'grep' work fine on run lines, as you see above, there are a lot
510 of caveats due to interaction with Tcl syntax, and we want to make sure the
511 run lines are portable to a wide range of systems. Another major problem is
512 that grep is not very good at checking to verify that the output of a tools
513 contains a series of different output in a specific order. The FileCheck
514 tool was designed to help with these problems.</p>
516 <p>FileCheck (whose basic command line arguments are described in <a
517 href="http://llvm.org/cmds/FileCheck.html">the FileCheck man page</a> is
518 designed to read a file to check from standard input, and the set of things
519 to verify from a file specified as a command line argument. A simple example
520 of using FileCheck from a RUN line looks like this:</p>
522 <div class="doc_code">
524 ; RUN: llvm-as < %s | llc -march=x86-64 | <b>FileCheck %s</b>
528 <p>This syntax says to pipe the current file ("%s") into llvm-as, pipe that into
529 llc, then pipe the output of llc into FileCheck. This means that FileCheck will
530 be verifying its standard input (the llc output) against the filename argument
531 specified (the original .ll file specified by "%s"). To see how this works,
532 lets look at the rest of the .ll file (after the RUN line):</p>
534 <div class="doc_code">
536 define void @sub1(i32* %p, i32 %v) {
538 ; <b>CHECK: sub1:</b>
540 %0 = tail call i32 @llvm.atomic.load.sub.i32.p0i32(i32* %p, i32 %v)
544 define void @inc4(i64* %p) {
546 ; <b>CHECK: inc4:</b>
548 %0 = tail call i64 @llvm.atomic.load.add.i64.p0i64(i64* %p, i64 1)
554 <p>Here you can see some "CHECK:" lines specified in comments. Now you can see
555 how the file is piped into llvm-as, then llc, and the machine code output is
556 what we are verifying. FileCheck checks the machine code output to verify that
557 it matches what the "CHECK:" lines specify.</p>
559 <p>The syntax of the CHECK: lines is very simple: they are fixed strings that
560 must occur in order. FileCheck defaults to ignoring horizontal whitespace
561 differences (e.g. a space is allowed to match a tab) but otherwise, the contents
562 of the CHECK: line is required to match some thing in the test file exactly.</p>
564 <p>One nice thing about FileCheck (compared to grep) is that it allows merging
565 test cases together into logical groups. For example, because the test above
566 is checking for the "sub1:" and "inc4:" labels, it will not match unless there
567 is a "subl" in between those labels. If it existed somewhere else in the file,
568 that would not count: "grep subl" matches if subl exists anywhere in the
571 <!-- _______________________________________________________________________ -->
573 <a name="FileCheck-check-prefix">The FileCheck -check-prefix option</a>
578 <p>The FileCheck -check-prefix option allows multiple test configurations to be
579 driven from one .ll file. This is useful in many circumstances, for example,
580 testing different architectural variants with llc. Here's a simple example:</p>
582 <div class="doc_code">
584 ; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin9 -mattr=sse41 \
585 ; RUN: | <b>FileCheck %s -check-prefix=X32</b>
586 ; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 -mattr=sse41 \
587 ; RUN: | <b>FileCheck %s -check-prefix=X64</b>
589 define <4 x i32> @pinsrd_1(i32 %s, <4 x i32> %tmp) nounwind {
590 %tmp1 = insertelement <4 x i32> %tmp, i32 %s, i32 1
591 ret <4 x i32> %tmp1
592 ; <b>X32:</b> pinsrd_1:
593 ; <b>X32:</b> pinsrd $1, 4(%esp), %xmm0
595 ; <b>X64:</b> pinsrd_1:
596 ; <b>X64:</b> pinsrd $1, %edi, %xmm0
601 <p>In this case, we're testing that we get the expected code generation with
602 both 32-bit and 64-bit code generation.</p>
606 <!-- _______________________________________________________________________ -->
608 <a name="FileCheck-CHECK-NEXT">The "CHECK-NEXT:" directive</a>
613 <p>Sometimes you want to match lines and would like to verify that matches
614 happen on exactly consecutive lines with no other lines in between them. In
615 this case, you can use CHECK: and CHECK-NEXT: directives to specify this. If
616 you specified a custom check prefix, just use "<PREFIX>-NEXT:". For
617 example, something like this works as you'd expect:</p>
619 <div class="doc_code">
621 define void @t2(<2 x double>* %r, <2 x double>* %A, double %B) {
622 %tmp3 = load <2 x double>* %A, align 16
623 %tmp7 = insertelement <2 x double> undef, double %B, i32 0
624 %tmp9 = shufflevector <2 x double> %tmp3,
625 <2 x double> %tmp7,
626 <2 x i32> < i32 0, i32 2 >
627 store <2 x double> %tmp9, <2 x double>* %r, align 16
631 ; <b>CHECK:</b> movl 8(%esp), %eax
632 ; <b>CHECK-NEXT:</b> movapd (%eax), %xmm0
633 ; <b>CHECK-NEXT:</b> movhpd 12(%esp), %xmm0
634 ; <b>CHECK-NEXT:</b> movl 4(%esp), %eax
635 ; <b>CHECK-NEXT:</b> movapd %xmm0, (%eax)
636 ; <b>CHECK-NEXT:</b> ret
641 <p>CHECK-NEXT: directives reject the input unless there is exactly one newline
642 between it an the previous directive. A CHECK-NEXT cannot be the first
643 directive in a file.</p>
647 <!-- _______________________________________________________________________ -->
649 <a name="FileCheck-CHECK-NOT">The "CHECK-NOT:" directive</a>
654 <p>The CHECK-NOT: directive is used to verify that a string doesn't occur
655 between two matches (or the first match and the beginning of the file). For
656 example, to verify that a load is removed by a transformation, a test like this
659 <div class="doc_code">
661 define i8 @coerce_offset0(i32 %V, i32* %P) {
662 store i32 %V, i32* %P
664 %P2 = bitcast i32* %P to i8*
665 %P3 = getelementptr i8* %P2, i32 2
669 ; <b>CHECK:</b> @coerce_offset0
670 ; <b>CHECK-NOT:</b> load
671 ; <b>CHECK:</b> ret i8
678 <!-- _______________________________________________________________________ -->
680 <a name="FileCheck-Matching">FileCheck Pattern Matching Syntax</a>
685 <p>The CHECK: and CHECK-NOT: directives both take a pattern to match. For most
686 uses of FileCheck, fixed string matching is perfectly sufficient. For some
687 things, a more flexible form of matching is desired. To support this, FileCheck
688 allows you to specify regular expressions in matching strings, surrounded by
689 double braces: <b>{{yourregex}}</b>. Because we want to use fixed string
690 matching for a majority of what we do, FileCheck has been designed to support
691 mixing and matching fixed string matching with regular expressions. This allows
692 you to write things like this:</p>
694 <div class="doc_code">
696 ; CHECK: movhpd <b>{{[0-9]+}}</b>(%esp), <b>{{%xmm[0-7]}}</b>
700 <p>In this case, any offset from the ESP register will be allowed, and any xmm
701 register will be allowed.</p>
703 <p>Because regular expressions are enclosed with double braces, they are
704 visually distinct, and you don't need to use escape characters within the double
705 braces like you would in C. In the rare case that you want to match double
706 braces explicitly from the input, you can use something ugly like
707 <b>{{[{][{]}}</b> as your pattern.</p>
711 <!-- _______________________________________________________________________ -->
713 <a name="FileCheck-Variables">FileCheck Variables</a>
718 <p>It is often useful to match a pattern and then verify that it occurs again
719 later in the file. For codegen tests, this can be useful to allow any register,
720 but verify that that register is used consistently later. To do this, FileCheck
721 allows named variables to be defined and substituted into patterns. Here is a
724 <div class="doc_code">
727 ; CHECK: notw <b>[[REGISTER:%[a-z]+]]</b>
728 ; CHECK: andw {{.*}}<b>[[REGISTER]]</b>
732 <p>The first check line matches a regex (<tt>%[a-z]+</tt>) and captures it into
733 the variables "REGISTER". The second line verifies that whatever is in REGISTER
734 occurs later in the file after an "andw". FileCheck variable references are
735 always contained in <tt>[[ ]]</tt> pairs, are named, and their names can be
736 formed with the regex "<tt>[a-zA-Z][a-zA-Z0-9]*</tt>". If a colon follows the
737 name, then it is a definition of the variable, if not, it is a use.</p>
739 <p>FileCheck variables can be defined multiple times, and uses always get the
740 latest value. Note that variables are all read at the start of a "CHECK" line
741 and are all defined at the end. This means that if you have something like
742 "<tt>CHECK: [[XYZ:.*]]x[[XYZ]]</tt>" that the check line will read the previous
743 value of the XYZ variable and define a new one after the match is performed. If
744 you need to do something like this you can probably take advantage of the fact
745 that FileCheck is not actually line-oriented when it matches, this allows you to
746 define two separate CHECK lines that match on the same line.
753 <!-- _______________________________________________________________________ -->
754 <h3><a name="rtvars">Variables and substitutions</a></h3>
755 <!-- _______________________________________________________________________ -->
757 <p>With a RUN line there are a number of substitutions that are permitted. In
758 general, any Tcl variable that is available in the <tt>substitute</tt>
759 function (in <tt>test/lib/llvm.exp</tt>) can be substituted into a RUN line.
760 To make a substitution just write the variable's name preceded by a $.
761 Additionally, for compatibility reasons with previous versions of the test
762 library, certain names can be accessed with an alternate syntax: a % prefix.
763 These alternates are deprecated and may go away in a future version.
765 <p>Here are the available variable names. The alternate syntax is listed in
768 <dl style="margin-left: 25px">
769 <dt><b>$test</b> (%s)</dt>
770 <dd>The full path to the test case's source. This is suitable for passing
771 on the command line as the input to an llvm tool.</dd>
773 <dt><b>$srcdir</b></dt>
774 <dd>The source directory from where the "<tt>make check</tt>" was run.</dd>
776 <dt><b>objdir</b></dt>
777 <dd>The object directory that corresponds to the <tt>$srcdir</tt>.</dd>
779 <dt><b>subdir</b></dt>
780 <dd>A partial path from the <tt>test</tt> directory that contains the
781 sub-directory that contains the test source being executed.</dd>
783 <dt><b>srcroot</b></dt>
784 <dd>The root directory of the LLVM src tree.</dd>
786 <dt><b>objroot</b></dt>
787 <dd>The root directory of the LLVM object tree. This could be the same
791 <dd>The path to the directory that contains the test case source. This is
792 for locating any supporting files that are not generated by the test, but
793 used by the test.</dd>
796 <dd>The path to a temporary file name that could be used for this test case.
797 The file name won't conflict with other test cases. You can append to it if
798 you need multiple temporaries. This is useful as the destination of some
799 redirected output.</dd>
801 <dt><b>llvmlibsdir</b> (%llvmlibsdir)</dt>
802 <dd>The directory where the LLVM libraries are located.</dd>
804 <dt><b>target_triplet</b> (%target_triplet)</dt>
805 <dd>The target triplet that corresponds to the current host machine (the one
806 running the test cases). This should probably be called "host".<dd>
808 <dt><b>llvmgcc</b> (%llvmgcc)</dt>
809 <dd>The full path to the <tt>llvm-gcc</tt> executable as specified in the
810 configured LLVM environment</dd>
812 <dt><b>llvmgxx</b> (%llvmgxx)</dt>
813 <dd>The full path to the <tt>llvm-gxx</tt> executable as specified in the
814 configured LLVM environment</dd>
816 <dt><b>gccpath</b></dt>
817 <dd>The full path to the C compiler used to <i>build </i> LLVM. Note that
818 this might not be gcc.</dd>
820 <dt><b>gxxpath</b></dt>
821 <dd>The full path to the C++ compiler used to <i>build </i> LLVM. Note that
822 this might not be g++.</dd>
824 <dt><b>compile_c</b> (%compile_c)</dt>
825 <dd>The full command line used to compile LLVM C source code. This has all
826 the configured -I, -D and optimization options.</dd>
828 <dt><b>compile_cxx</b> (%compile_cxx)</dt>
829 <dd>The full command used to compile LLVM C++ source code. This has
830 all the configured -I, -D and optimization options.</dd>
832 <dt><b>link</b> (%link)</dt>
833 <dd>This full link command used to link LLVM executables. This has all the
834 configured -I, -L and -l options.</dd>
836 <dt><b>shlibext</b> (%shlibext)</dt>
837 <dd>The suffix for the host platforms share library (dll) files. This
838 includes the period as the first character.</dd>
840 <p>To add more variables, two things need to be changed. First, add a line in
841 the <tt>test/Makefile</tt> that creates the <tt>site.exp</tt> file. This will
842 "set" the variable as a global in the site.exp file. Second, in the
843 <tt>test/lib/llvm.exp</tt> file, in the substitute proc, add the variable name
844 to the list of "global" declarations at the beginning of the proc. That's it,
845 the variable can then be used in test scripts.</p>
848 <!-- _______________________________________________________________________ -->
849 <h3><a name="rtfeatures">Other Features</a></h3>
850 <!-- _______________________________________________________________________ -->
852 <p>To make RUN line writing easier, there are several shell scripts located
853 in the <tt>llvm/test/Scripts</tt> directory. This directory is in the PATH
854 when running tests, so you can just call these scripts using their name. For
857 <dt><b>ignore</b></dt>
858 <dd>This script runs its arguments and then always returns 0. This is useful
859 in cases where the test needs to cause a tool to generate an error (e.g. to
860 check the error output). However, any program in a pipeline that returns a
861 non-zero result will cause the test to fail. This script overcomes that
862 issue and nicely documents that the test case is purposefully ignoring the
863 result code of the tool</dd>
866 <dd>This script runs its arguments and then inverts the result code from
867 it. Zero result codes become 1. Non-zero result codes become 0. This is
868 useful to invert the result of a grep. For example "not grep X" means
869 succeed only if you don't find X in the input.</dd>
872 <p>Sometimes it is necessary to mark a test case as "expected fail" or XFAIL.
873 You can easily mark a test as XFAIL just by including <tt>XFAIL: </tt> on a
874 line near the top of the file. This signals that the test case should succeed
875 if the test fails. Such test cases are counted separately by the testing tool. To
876 specify an expected fail, use the XFAIL keyword in the comments of the test
877 program followed by a colon and one or more regular expressions (separated by
878 a comma). The regular expressions allow you to XFAIL the test conditionally by
879 host platform. The regular expressions following the : are matched against the
880 target triplet for the host machine. If there is a match, the test is expected
881 to fail. If not, the test is expected to succeed. To XFAIL everywhere just
882 specify <tt>XFAIL: *</tt>. Here is an example of an <tt>XFAIL</tt> line:</p>
884 <div class="doc_code">
890 <p>To make the output more useful, the <tt>llvm_runtest</tt> function wil
891 scan the lines of the test case for ones that contain a pattern that matches
892 PR[0-9]+. This is the syntax for specifying a PR (Problem Report) number that
893 is related to the test case. The number after "PR" specifies the LLVM bugzilla
894 number. When a PR number is specified, it will be used in the pass/fail
895 reporting. This is useful to quickly get some context when a test fails.</p>
897 <p>Finally, any line that contains "END." will cause the special
898 interpretation of lines to terminate. This is generally done right after the
899 last RUN: line. This has two side effects: (a) it prevents special
900 interpretation of lines that are part of the test program, not the
901 instructions to the test case, and (b) it speeds things up for really big test
902 cases by avoiding interpretation of the remainder of the file.</p>
908 <!--=========================================================================-->
909 <h2><a name="testsuitestructure">Test suite Structure</a></h2>
910 <!--=========================================================================-->
914 <p>The <tt>test-suite</tt> module contains a number of programs that can be compiled
915 with LLVM and executed. These programs are compiled using the native compiler
916 and various LLVM backends. The output from the program compiled with the
917 native compiler is assumed correct; the results from the other programs are
918 compared to the native program output and pass if they match.</p>
920 <p>When executing tests, it is usually a good idea to start out with a subset of
921 the available tests or programs. This makes test run times smaller at first and
922 later on this is useful to investigate individual test failures. To run some
923 test only on a subset of programs, simply change directory to the programs you
924 want tested and run <tt>gmake</tt> there. Alternatively, you can run a different
925 test using the <tt>TEST</tt> variable to change what tests or run on the
926 selected programs (see below for more info).</p>
928 <p>In addition for testing correctness, the <tt>test-suite</tt> directory also
929 performs timing tests of various LLVM optimizations. It also records
930 compilation times for the compilers and the JIT. This information can be
931 used to compare the effectiveness of LLVM's optimizations and code
934 <p><tt>test-suite</tt> tests are divided into three types of tests: MultiSource,
935 SingleSource, and External.</p>
938 <li><tt>test-suite/SingleSource</tt>
939 <p>The SingleSource directory contains test programs that are only a single
940 source file in size. These are usually small benchmark programs or small
941 programs that calculate a particular value. Several such programs are grouped
942 together in each directory.</p></li>
944 <li><tt>test-suite/MultiSource</tt>
945 <p>The MultiSource directory contains subdirectories which contain entire
946 programs with multiple source files. Large benchmarks and whole applications
949 <li><tt>test-suite/External</tt>
950 <p>The External directory contains Makefiles for building code that is external
951 to (i.e., not distributed with) LLVM. The most prominent members of this
952 directory are the SPEC 95 and SPEC 2000 benchmark suites. The <tt>External</tt>
953 directory does not contain these actual tests, but only the Makefiles that know
954 how to properly compile these programs from somewhere else. The presence and
955 location of these external programs is configured by the test-suite
956 <tt>configure</tt> script.</p></li>
959 <p>Each tree is then subdivided into several categories, including applications,
960 benchmarks, regression tests, code that is strange grammatically, etc. These
961 organizations should be relatively self explanatory.</p>
963 <p>Some tests are known to fail. Some are bugs that we have not fixed yet;
964 others are features that we haven't added yet (or may never add). In the
965 regression tests, the result for such tests will be XFAIL (eXpected FAILure).
966 In this way, you can tell the difference between an expected and unexpected
969 <p>The tests in the test suite have no such feature at this time. If the
970 test passes, only warnings and other miscellaneous output will be generated. If
971 a test fails, a large <program> FAILED message will be displayed. This
972 will help you separate benign warnings from actual test failures.</p>
976 <!--=========================================================================-->
977 <h2><a name="testsuiterun">Running the test suite</a></h2>
978 <!--=========================================================================-->
982 <p>First, all tests are executed within the LLVM object directory tree. They
983 <i>are not</i> executed inside of the LLVM source tree. This is because the
984 test suite creates temporary files during execution.</p>
986 <p>To run the test suite, you need to use the following steps:</p>
989 <li><tt>cd</tt> into the <tt>llvm/projects</tt> directory in your source tree.
992 <li><p>Check out the <tt>test-suite</tt> module with:</p>
994 <div class="doc_code">
996 % svn co http://llvm.org/svn/llvm-project/test-suite/trunk test-suite
999 <p>This will get the test suite into <tt>llvm/projects/test-suite</tt>.</p>
1001 <li><p>Configure and build <tt>llvm</tt>.</p></li>
1002 <li><p>Configure and build <tt>llvm-gcc</tt>.</p></li>
1003 <li><p>Install <tt>llvm-gcc</tt> somewhere.</p></li>
1004 <li><p><em>Re-configure</em> <tt>llvm</tt> from the top level of
1005 each build tree (LLVM object directory tree) in which you want
1006 to run the test suite, just as you do before building LLVM.</p>
1007 <p>During the <em>re-configuration</em>, you must either: (1)
1008 have <tt>llvm-gcc</tt> you just built in your path, or (2)
1009 specify the directory where your just-built <tt>llvm-gcc</tt> is
1010 installed using <tt>--with-llvmgccdir=$LLVM_GCC_DIR</tt>.</p>
1011 <p>You must also tell the configure machinery that the test suite
1012 is available so it can be configured for your build tree:</p>
1013 <div class="doc_code">
1015 % cd $LLVM_OBJ_ROOT ; $LLVM_SRC_ROOT/configure [--with-llvmgccdir=$LLVM_GCC_DIR]
1018 <p>[Remember that <tt>$LLVM_GCC_DIR</tt> is the directory where you
1019 <em>installed</em> llvm-gcc, not its src or obj directory.]</p>
1022 <li><p>You can now run the test suite from your build tree as follows:</p>
1023 <div class="doc_code">
1025 % cd $LLVM_OBJ_ROOT/projects/test-suite
1031 <p>Note that the second and third steps only need to be done once. After you
1032 have the suite checked out and configured, you don't need to do it again (unless
1033 the test code or configure script changes).</p>
1035 <!-- _______________________________________________________________________ -->
1037 <a name="testsuiteexternal">Configuring External Tests</a>
1039 <!-- _______________________________________________________________________ -->
1042 <p>In order to run the External tests in the <tt>test-suite</tt>
1043 module, you must specify <i>--with-externals</i>. This
1044 must be done during the <em>re-configuration</em> step (see above),
1045 and the <tt>llvm</tt> re-configuration must recognize the
1046 previously-built <tt>llvm-gcc</tt>. If any of these is missing or
1047 neglected, the External tests won't work.</p>
1049 <dt><i>--with-externals</i></dt>
1050 <dt><i>--with-externals=<<tt>directory</tt>></i></dt>
1052 This tells LLVM where to find any external tests. They are expected to be
1053 in specifically named subdirectories of <<tt>directory</tt>>.
1054 If <tt>directory</tt> is left unspecified,
1055 <tt>configure</tt> uses the default value
1056 <tt>/home/vadve/shared/benchmarks/speccpu2000/benchspec</tt>.
1057 Subdirectory names known to LLVM include:
1060 <dt>speccpu2000</dt>
1061 <dt>speccpu2006</dt>
1064 Others are added from time to time, and can be determined from
1068 <!-- _______________________________________________________________________ -->
1070 <a name="testsuitetests">Running different tests</a>
1072 <!-- _______________________________________________________________________ -->
1074 <p>In addition to the regular "whole program" tests, the <tt>test-suite</tt>
1075 module also provides a mechanism for compiling the programs in different ways.
1076 If the variable TEST is defined on the <tt>gmake</tt> command line, the test system will
1077 include a Makefile named <tt>TEST.<value of TEST variable>.Makefile</tt>.
1078 This Makefile can modify build rules to yield different results.</p>
1080 <p>For example, the LLVM nightly tester uses <tt>TEST.nightly.Makefile</tt> to
1081 create the nightly test reports. To run the nightly tests, run <tt>gmake
1082 TEST=nightly</tt>.</p>
1084 <p>There are several TEST Makefiles available in the tree. Some of them are
1085 designed for internal LLVM research and will not work outside of the LLVM
1086 research group. They may still be valuable, however, as a guide to writing your
1087 own TEST Makefile for any optimization or analysis passes that you develop with
1092 <!-- _______________________________________________________________________ -->
1094 <a name="testsuiteoutput">Generating test output</a>
1096 <!-- _______________________________________________________________________ -->
1098 <p>There are a number of ways to run the tests and generate output. The most
1099 simple one is simply running <tt>gmake</tt> with no arguments. This will
1100 compile and run all programs in the tree using a number of different methods
1101 and compare results. Any failures are reported in the output, but are likely
1102 drowned in the other output. Passes are not reported explicitely.</p>
1104 <p>Somewhat better is running <tt>gmake TEST=sometest test</tt>, which runs
1105 the specified test and usually adds per-program summaries to the output
1106 (depending on which sometest you use). For example, the <tt>nightly</tt> test
1107 explicitely outputs TEST-PASS or TEST-FAIL for every test after each program.
1108 Though these lines are still drowned in the output, it's easy to grep the
1109 output logs in the Output directories.</p>
1111 <p>Even better are the <tt>report</tt> and <tt>report.format</tt> targets
1112 (where <tt>format</tt> is one of <tt>html</tt>, <tt>csv</tt>, <tt>text</tt> or
1113 <tt>graphs</tt>). The exact contents of the report are dependent on which
1114 <tt>TEST</tt> you are running, but the text results are always shown at the
1115 end of the run and the results are always stored in the
1116 <tt>report.<type>.format</tt> file (when running with
1117 <tt>TEST=<type></tt>).
1119 The <tt>report</tt> also generate a file called
1120 <tt>report.<type>.raw.out</tt> containing the output of the entire test
1124 <!-- _______________________________________________________________________ -->
1126 <a name="testsuitecustom">Writing custom tests for the test suite</a>
1128 <!-- _______________________________________________________________________ -->
1132 <p>Assuming you can run the test suite, (e.g. "<tt>gmake TEST=nightly report</tt>"
1133 should work), it is really easy to run optimizations or code generator
1134 components against every program in the tree, collecting statistics or running
1135 custom checks for correctness. At base, this is how the nightly tester works,
1136 it's just one example of a general framework.</p>
1138 <p>Lets say that you have an LLVM optimization pass, and you want to see how
1139 many times it triggers. First thing you should do is add an LLVM
1140 <a href="ProgrammersManual.html#Statistic">statistic</a> to your pass, which
1141 will tally counts of things you care about.</p>
1143 <p>Following this, you can set up a test and a report that collects these and
1144 formats them for easy viewing. This consists of two files, a
1145 "<tt>test-suite/TEST.XXX.Makefile</tt>" fragment (where XXX is the name of your
1146 test) and a "<tt>test-suite/TEST.XXX.report</tt>" file that indicates how to
1147 format the output into a table. There are many example reports of various
1148 levels of sophistication included with the test suite, and the framework is very
1151 <p>If you are interested in testing an optimization pass, check out the
1152 "libcalls" test as an example. It can be run like this:<p>
1154 <div class="doc_code">
1156 % cd llvm/projects/test-suite/MultiSource/Benchmarks # or some other level
1157 % make TEST=libcalls report
1161 <p>This will do a bunch of stuff, then eventually print a table like this:</p>
1163 <div class="doc_code">
1165 Name | total | #exit |
1167 FreeBench/analyzer/analyzer | 51 | 6 |
1168 FreeBench/fourinarow/fourinarow | 1 | 1 |
1169 FreeBench/neural/neural | 19 | 9 |
1170 FreeBench/pifft/pifft | 5 | 3 |
1171 MallocBench/cfrac/cfrac | 1 | * |
1172 MallocBench/espresso/espresso | 52 | 12 |
1173 MallocBench/gs/gs | 4 | * |
1174 Prolangs-C/TimberWolfMC/timberwolfmc | 302 | * |
1175 Prolangs-C/agrep/agrep | 33 | 12 |
1176 Prolangs-C/allroots/allroots | * | * |
1177 Prolangs-C/assembler/assembler | 47 | * |
1178 Prolangs-C/bison/mybison | 74 | * |
1183 <p>This basically is grepping the -stats output and displaying it in a table.
1184 You can also use the "TEST=libcalls report.html" target to get the table in HTML
1185 form, similarly for report.csv and report.tex.</p>
1187 <p>The source for this is in test-suite/TEST.libcalls.*. The format is pretty
1188 simple: the Makefile indicates how to run the test (in this case,
1189 "<tt>opt -simplify-libcalls -stats</tt>"), and the report contains one line for
1190 each column of the output. The first value is the header for the column and the
1191 second is the regex to grep the output of the command for. There are lots of
1192 example reports that can do fancy stuff.</p>
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