1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>LLVM Testing Infrastructure Guide</title>
<link rel="stylesheet" href="llvm.css" type="text/css">
</head>
<body>
<h1>
LLVM Testing Infrastructure Guide
</h1>
<ol>
<li><a href="#overview">Overview</a></li>
<li><a href="#requirements">Requirements</a></li>
<li><a href="#org">LLVM testing infrastructure organization</a>
<ul>
<li><a href="#regressiontests">Regression tests</a></li>
<li><a href="#testsuite"><tt>test-suite</tt></a></li>
<li><a href="#debuginfotests">Debugging Information tests</a></li>
</ul>
</li>
<li><a href="#quick">Quick start</a>
<ul>
<li><a href="#quickregressiontests">Regression tests</a></li>
<li><a href="#quickdebuginfotests">Debugging Information tests</a></li>
</ul>
</li>
<li><a href="#rtstructure">Regression test structure</a>
<ul>
<li><a href="#rtcustom">Writing new regression tests</a></li>
<li><a href="#FileCheck">The FileCheck utility</a></li>
<li><a href="#rtvars">Variables and substitutions</a></li>
<li><a href="#rtfeatures">Other features</a></li>
</ul>
</li>
<li><a href="#testsuiteoverview"><tt>test-suite</tt> Overview</a>
<ul>
<li><a href="#testsuitequickstart"><tt>test-suite</tt> Quickstart</a></li>
<li><a href="#testsuitemakefiles"><tt>test-suite</tt> Makefiles</a></li>
</ul>
</li>
</ol>
<div class="doc_author">
<p>Written by John T. Criswell, Daniel Dunbar, Reid Spencer, and Tanya Lattner</p>
</div>
<!--=========================================================================-->
<h2><a name="overview">Overview</a></h2>
<!--=========================================================================-->
<div>
<p>This document is the reference manual for the LLVM testing infrastructure. It
documents the structure of the LLVM testing infrastructure, the tools needed to
use it, and how to add and run tests.</p>
</div>
<!--=========================================================================-->
<h2><a name="requirements">Requirements</a></h2>
<!--=========================================================================-->
<div>
<p>In order to use the LLVM testing infrastructure, you will need all of the
software required to build LLVM, as well
as <a href="http://python.org">Python</a> 2.4 or later.</p>
</div>
<!--=========================================================================-->
<h2><a name="org">LLVM testing infrastructure organization</a></h2>
<!--=========================================================================-->
<div>
<p>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 <tt>llvm/test</tt> and are expected to always
pass -- they should be run before every commit.</p>
<p>The whole programs tests are referred to as the "LLVM test suite" (or
"test-suite") and are in the <tt>test-suite</tt> 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.</p>
<!-- _______________________________________________________________________ -->
<h3><a name="regressiontests">Regression tests</a></h3>
<!-- _______________________________________________________________________ -->
<div>
<p>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 <tt>--with-llvmgcc</tt>
options were used at <tt>configure</tt> time of the <tt>llvm</tt> module). These
tests are driven by the 'lit' testing tool, which is part of LLVM.</p>
<p>These code fragments are not complete programs. The code generated
from them is never executed to determine correct behavior.</p>
<p>These code fragment tests are located in the <tt>llvm/test</tt>
directory.</p>
<p>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.</p>
</div>
<!-- _______________________________________________________________________ -->
<h3><a name="testsuite"><tt>test-suite</tt></a></h3>
<!-- _______________________________________________________________________ -->
<div>
<p>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++.</p>
<p>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.</p>
<p>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.</p>
<p>The test-suite is located in the <tt>test-suite</tt> Subversion module.</p>
</div>
<!-- _______________________________________________________________________ -->
<h3><a name="debuginfotests">Debugging Information tests</a></h3>
<!-- _______________________________________________________________________ -->
<div>
<p>The test suite contains tests to check quality of debugging information.
The test are written in C based languages or in LLVM assembly language. </p>
<p>These tests are compiled and run under a debugger. The debugger output
is checked to validate of debugging information. See README.txt in the
test suite for more information . This test suite is located in the
<tt>debuginfo-tests</tt> Subversion module. </p>
</div>
</div>
<!--=========================================================================-->
<h2><a name="quick">Quick start</a></h2>
<!--=========================================================================-->
<div>
<p>The tests are located in two separate Subversion modules. The regressions
tests are in the main "llvm" module under the directory
<tt>llvm/test</tt> (so you get these tests for free with the main llvm
tree). Use "make check-all" to run the regression tests after building
LLVM.</p>
<p>The more comprehensive test suite that includes whole programs in C and C++
is in the <tt>test-suite</tt>
module. See <a href="#testsuitequickstart"><tt>test-suite</tt> Quickstart</a>
for more information on running these tests.</p>
<!-- _______________________________________________________________________ -->
<h3><a name="quickregressiontests">Regression tests</a></h3>
<div>
<!-- _______________________________________________________________________ -->
<p>To run all of the LLVM regression tests, use master Makefile in
the <tt>llvm/test</tt> directory:</p>
<div class="doc_code">
<pre>
% gmake -C llvm/test
</pre>
</div>
<p>or</p>
<div class="doc_code">
<pre>
% gmake check
</pre>
</div>
<p>If you have <a href="http://clang.llvm.org/">Clang</a> checked out and built,
you can run the LLVM and Clang tests simultaneously using:</p>
<p>or</p>
<div class="doc_code">
<pre>
% gmake check-all
</pre>
</div>
<p>To run the tests with Valgrind (Memcheck by default), just append
<tt>VG=1</tt> to the commands above, e.g.:</p>
<div class="doc_code">
<pre>
% gmake check VG=1
</pre>
</div>
<p>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:</p>
<div class="doc_code">
<pre>
% llvm-lit ~/llvm/test/Integer/BitCast.ll
</pre>
</div>
<p>or to run all of the ARM CodeGen tests:</p>
<div class="doc_code">
<pre>
% llvm-lit ~/llvm/test/CodeGen/ARM
</pre>
</div>
<p>For more information on using the 'lit' tool, see 'llvm-lit --help' or the
'lit' man page.</p>
</div>
<!-- _______________________________________________________________________ -->
<h3><a name="quickdebuginfotests">Debugging Information tests</a></h3>
<div>
<!-- _______________________________________________________________________ -->
<div>
<p> To run debugging information tests simply checkout the tests inside
clang/test directory. </p>
<div class="doc_code">
<pre>
%cd clang/test
% svn co http://llvm.org/svn/llvm-project/debuginfo-tests/trunk debuginfo-tests
</pre>
</div>
<p> These tests are already set up to run as part of clang regression tests.</p>
</div>
</div>
</div>
<!--=========================================================================-->
<h2><a name="rtstructure">Regression test structure</a></h2>
<!--=========================================================================-->
<div>
<p>The LLVM regression tests are driven by 'lit' and are located in
the <tt>llvm/test</tt> directory.
<p>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:</p>
<ul>
<li><tt>Analysis</tt>: checks Analysis passes.</li>
<li><tt>Archive</tt>: checks the Archive library.</li>
<li><tt>Assembler</tt>: checks Assembly reader/writer functionality.</li>
<li><tt>Bitcode</tt>: checks Bitcode reader/writer functionality.</li>
<li><tt>CodeGen</tt>: checks code generation and each target.</li>
<li><tt>Features</tt>: checks various features of the LLVM language.</li>
<li><tt>Linker</tt>: tests bitcode linking.</li>
<li><tt>Transforms</tt>: tests each of the scalar, IPO, and utility
transforms to ensure they make the right transformations.</li>
<li><tt>Verifier</tt>: tests the IR verifier.</li>
</ul>
<!-- _______________________________________________________________________ -->
<h3><a name="rtcustom">Writing new regression tests</a></h3>
<!-- _______________________________________________________________________ -->
<div>
<p>The regression test structure is very simple, but does require some
information to be set. This information is gathered via <tt>configure</tt> and
is written to a file, <tt>lit.site.cfg</tt>
in <tt>llvm/test</tt>. The <tt>llvm/test</tt> Makefile does this work for
you.</p>
<p>In order for the regression tests to work, each directory of tests must
have a <tt>dg.exp</tt> file. Lit looks for this file to determine how to
run the tests. This file is just a Tcl script and it can do anything you want,
but we've standardized it for the LLVM regression tests. If you're adding a
directory of tests, just copy <tt>dg.exp</tt> from another directory to get
running. The standard <tt>dg.exp</tt> simply loads a Tcl library
(<tt>test/lib/llvm.exp</tt>) and calls the <tt>llvm_runtests</tt> function
defined in that library with a list of file names to run. The names are
obtained by using Tcl's glob command. Any directory that contains only
directories does not need the <tt>dg.exp</tt> file.</p>
<p>The <tt>llvm-runtests</tt> 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
<tt>llvm-runtests</tt> function will issue an error and the test will
fail.</p>
<p>RUN lines are specified in the comments of the test program using the
keyword <tt>RUN</tt> followed by a colon, and lastly the command (pipeline)
to execute. Together, these lines form the "script" that
<tt>llvm-runtests</tt> 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 <i>look</i> like a shell script, they are not. RUN lines are interpreted
directly by the Tcl <tt>exec</tt> 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.</p>
<p>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.</p>
<p>Each RUN line is executed on its own, distinct from other lines unless
its last character is <tt>\</tt>. 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
<tt>\</tt> are concatenated until a RUN line that doesn't end in <tt>\</tt> 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.
</p>
<p> Below is an example of legal RUN lines in a <tt>.ll</tt> file:</p>
<div class="doc_code">
<pre>
; RUN: llvm-as < %s | llvm-dis > %t1
; RUN: llvm-dis < %s.bc-13 > %t2
; RUN: diff %t1 %t2
</pre>
</div>
<p>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
<a href="http://www.tcl.tk/man/tcl8.5/TclCmd/exec.htm#M2">Tcl exec</a>
command and the
<a href="http://www.tcl.tk/man/tcl8.5/tutorial/Tcl26.html">tutorial</a>.
The major differences are:</p>
<ul>
<li>You can't do <tt>2>&1</tt>. That will cause Tcl to write to a
file named <tt>&1</tt>. Usually this is done to get stderr to go through
a pipe. You can do that in tcl with <tt>|&</tt> so replace this idiom:
<tt>... 2>&1 | grep</tt> with <tt>... |& grep</tt></li>
<li>You can only redirect to a file, not to another descriptor and not from
a here document.</li>
<li>tcl supports redirecting to open files with the @ syntax but you
shouldn't use that here.</li>
</ul>
<p>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:</p>
<div class="doc_code">
<pre>
... | grep 'find this string'
</pre>
</div>
<p>This will fail because the ' characters are passed to grep. This would
instruction grep to look for <tt>'find</tt> in the files <tt>this</tt> and
<tt>string'</tt>. To avoid this use curly braces to tell Tcl that it should
treat everything enclosed as one value. So our example would become:</p>
<div class="doc_code">
<pre>
... | grep {find this string}
</pre>
</div>
<p>Additionally, the characters <tt>[</tt> and <tt>]</tt> 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:</p>
<div class="doc_code">
<pre>
... | grep bb[2-8]
</pre>
</div>
<p>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:</p>
<div class="doc_code">
<pre>
... | grep {bb\[2-8\]}
</pre>
</div>
<p>Finally, if you need to pass the <tt>\</tt> character down to a program,
then it must be doubled. This is another Tcl special character. So, suppose
you had:
<div class="doc_code">
<pre>
... | grep 'i32\*'
</pre>
</div>
<p>This will fail to match what you want (a pointer to i32). First, the
<tt>'</tt> do not get stripped off. Second, the <tt>\</tt> gets stripped off
by Tcl so what grep sees is: <tt>'i32*'</tt>. That's not likely to match
anything. To resolve this you must use <tt>\\</tt> and the <tt>{}</tt>, like
this:</p>
<div class="doc_code">
<pre>
... | grep {i32\\*}
</pre>
</div>
<p>If your system includes GNU <tt>grep</tt>, make sure
that <tt>GREP_OPTIONS</tt> is not set in your environment. Otherwise,
you may get invalid results (both false positives and false
negatives).</p>
</div>
<!-- _______________________________________________________________________ -->
<h3><a name="FileCheck">The FileCheck utility</a></h3>
<!-- _______________________________________________________________________ -->
<div>
<p>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.</p>
<p>FileCheck (whose basic command line arguments are described in <a
href="http://llvm.org/cmds/FileCheck.html">the FileCheck man page</a> 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:</p>
<div class="doc_code">
<pre>
; RUN: llvm-as < %s | llc -march=x86-64 | <b>FileCheck %s</b>
</pre>
</div>
<p>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,
lets look at the rest of the .ll file (after the RUN line):</p>
<div class="doc_code">
<pre>
define void @sub1(i32* %p, i32 %v) {
entry:
; <b>CHECK: sub1:</b>
; <b>CHECK: subl</b>
%0 = tail call i32 @llvm.atomic.load.sub.i32.p0i32(i32* %p, i32 %v)
ret void
}
define void @inc4(i64* %p) {
entry:
; <b>CHECK: inc4:</b>
; <b>CHECK: incq</b>
%0 = tail call i64 @llvm.atomic.load.add.i64.p0i64(i64* %p, i64 1)
ret void
}
</pre>
</div>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<!-- _______________________________________________________________________ -->
<h4>
<a name="FileCheck-check-prefix">The FileCheck -check-prefix option</a>
</h4>
<div>
<p>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:</p>
<div class="doc_code">
<pre>
; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin9 -mattr=sse41 \
; RUN: | <b>FileCheck %s -check-prefix=X32</b>
; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 -mattr=sse41 \
; RUN: | <b>FileCheck %s -check-prefix=X64</b>
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
; <b>X32:</b> pinsrd_1:
; <b>X32:</b> pinsrd $1, 4(%esp), %xmm0
; <b>X64:</b> pinsrd_1:
; <b>X64:</b> pinsrd $1, %edi, %xmm0
}
</pre>
</div>
<p>In this case, we're testing that we get the expected code generation with
both 32-bit and 64-bit code generation.</p>
</div>
<!-- _______________________________________________________________________ -->
<h4>
<a name="FileCheck-CHECK-NEXT">The "CHECK-NEXT:" directive</a>
</h4>
<div>
<p>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:</p>
<div class="doc_code">
<pre>
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
; <b>CHECK:</b> t2:
; <b>CHECK:</b> movl 8(%esp), %eax
; <b>CHECK-NEXT:</b> movapd (%eax), %xmm0
; <b>CHECK-NEXT:</b> movhpd 12(%esp), %xmm0
; <b>CHECK-NEXT:</b> movl 4(%esp), %eax
; <b>CHECK-NEXT:</b> movapd %xmm0, (%eax)
; <b>CHECK-NEXT:</b> ret
}
</pre>
</div>
<p>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.</p>
</div>
<!-- _______________________________________________________________________ -->
<h4>
<a name="FileCheck-CHECK-NOT">The "CHECK-NOT:" directive</a>
</h4>
<div>
<p>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:</p>
<div class="doc_code">
<pre>
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
; <b>CHECK:</b> @coerce_offset0
; <b>CHECK-NOT:</b> load
; <b>CHECK:</b> ret i8
}
</pre>
</div>
</div>
<!-- _______________________________________________________________________ -->
<h4>
<a name="FileCheck-Matching">FileCheck Pattern Matching Syntax</a>
</h4>
<div>
<p>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: <b>{{yourregex}}</b>. 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:</p>
<div class="doc_code">
<pre>
; CHECK: movhpd <b>{{[0-9]+}}</b>(%esp), <b>{{%xmm[0-7]}}</b>
</pre>
</div>
<p>In this case, any offset from the ESP register will be allowed, and any xmm
register will be allowed.</p>
<p>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
<b>{{[{][{]}}</b> as your pattern.</p>
</div>
<!-- _______________________________________________________________________ -->
<h4>
<a name="FileCheck-Variables">FileCheck Variables</a>
</h4>
<div>
<p>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:</p>
<div class="doc_code">
<pre>
; CHECK: test5:
; CHECK: notw <b>[[REGISTER:%[a-z]+]]</b>
; CHECK: andw {{.*}}<b>[[REGISTER]]</b>
</pre>
</div>
<p>The first check line matches a regex (<tt>%[a-z]+</tt>) 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 <tt>[[ ]]</tt> pairs, are named, and their names can be
formed with the regex "<tt>[a-zA-Z][a-zA-Z0-9]*</tt>". If a colon follows the
name, then it is a definition of the variable, if not, it is a use.</p>
<p>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
"<tt>CHECK: [[XYZ:.*]]x[[XYZ]]</tt>" 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.
</p>
</div>
</div>
<!-- _______________________________________________________________________ -->
<h3><a name="rtvars">Variables and substitutions</a></h3>
<!-- _______________________________________________________________________ -->
<div>
<p>With a RUN line there are a number of substitutions that are permitted. In
general, any Tcl variable that is available in the <tt>substitute</tt>
function (in <tt>test/lib/llvm.exp</tt>) can be substituted into a RUN line.
To make a substitution just write the variable's name preceded by a $.
Additionally, for compatibility reasons with previous versions of the test
library, certain names can be accessed with an alternate syntax: a % prefix.
These alternates are deprecated and may go away in a future version.
</p>
<p>Here are the available variable names. The alternate syntax is listed in
parentheses.</p>
<dl style="margin-left: 25px">
<dt><b>$test</b> (%s)</dt>
<dd>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.</dd>
<dt><b>$srcdir</b></dt>
<dd>The source directory from where the "<tt>make check</tt>" was run.</dd>
<dt><b>objdir</b></dt>
<dd>The object directory that corresponds to the <tt>$srcdir</tt>.</dd>
<dt><b>subdir</b></dt>
<dd>A partial path from the <tt>test</tt> directory that contains the
sub-directory that contains the test source being executed.</dd>
<dt><b>srcroot</b></dt>
<dd>The root directory of the LLVM src tree.</dd>
<dt><b>objroot</b></dt>
<dd>The root directory of the LLVM object tree. This could be the same
as the srcroot.</dd>
<dt><b>path</b><dt>
<dd>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.</dd>
<dt><b>tmp</b></dt>
<dd>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.</dd>
<dt><b>target_triplet</b> (%target_triplet)</dt>
<dd>The target triplet that corresponds to the current host machine (the one
running the test cases). This should probably be called "host".<dd>
<dt><b>link</b> (%link)</dt>
<dd>This full link command used to link LLVM executables. This has all the
configured -I, -L and -l options.</dd>
<dt><b>shlibext</b> (%shlibext)</dt>
<dd>The suffix for the host platforms share library (dll) files. This
includes the period as the first character.</dd>
</dl>
<p>To add more variables, two things need to be changed. First, add a line in
the <tt>test/Makefile</tt> that creates the <tt>site.exp</tt> file. This will
"set" the variable as a global in the site.exp file. Second, in the
<tt>test/lib/llvm.exp</tt> 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.</p>
</div>
<!-- _______________________________________________________________________ -->
<h3><a name="rtfeatures">Other Features</a></h3>
<!-- _______________________________________________________________________ -->
<div>
<p>To make RUN line writing easier, there are several shell scripts located
in the <tt>llvm/test/Scripts</tt> directory. This directory is in the PATH
when running tests, so you can just call these scripts using their name. For
example:</p>
<dl>
<dt><b>ignore</b></dt>
<dd>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</dd>
<dt><b>not</b></dt>
<dd>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.</dd>
</dl>
<p>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 <tt>XFAIL: </tt> 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 <tt>XFAIL: *</tt>. Here is an example of an <tt>XFAIL</tt> line:</p>
<div class="doc_code">
<pre>
; XFAIL: darwin,sun
</pre>
</div>
<p>To make the output more useful, the <tt>llvm_runtest</tt> 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.</p>
<p>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.</p>
</div>
</div>
<!--=========================================================================-->
<h2><a name="testsuiteoverview"><tt>test-suite</tt> Overview</a></h2>
<!--=========================================================================-->
<div>
<p>The <tt>test-suite</tt> module contains a number of programs that can be
compiled and executed. The <tt>test-suite</tt> includes reference outputs for
all of the programs, so that the output of the executed program can be checked
for correctness.</p>
<p><tt>test-suite</tt> tests are divided into three types of tests: MultiSource,
SingleSource, and External.</p>
<ul>
<li><tt>test-suite/SingleSource</tt>
<p>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.</p></li>
<li><tt>test-suite/MultiSource</tt>
<p>The MultiSource directory contains subdirectories which contain entire
programs with multiple source files. Large benchmarks and whole applications
go here.</p></li>
<li><tt>test-suite/External</tt>
<p>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 <tt>External</tt>
directory does not contain these actual tests, but only the Makefiles that know
how to properly compile these programs from somewhere else. When
using <tt>LNT</tt>, use the <tt>--test-externals</tt> option to include these
tests in the results.</p></li>
</ul>
</div>
<!--=========================================================================-->
<h2><a name="testsuitequickstart"><tt>test-suite</tt> Quickstart</a></h2>
<!--=========================================================================-->
<div>
<p>The modern way of running the <tt>test-suite</tt> is focused on testing and
benchmarking complete compilers using
the <a href="http://llvm.org/docs/lnt">LNT</a> testing infrastructure.</p>
<p>For more information on using LNT to execute the <tt>test-suite</tt>, please
see the <a href="http://llvm.org/docs/lnt/quickstart.html">LNT Quickstart</a>
documentation.</p>
</div>
<!--=========================================================================-->
<h2><a name="testsuitemakefiles"><tt>test-suite</tt> Makefiles</a></h2>
<!--=========================================================================-->
<div>
<p>Historically, the <tt>test-suite</tt> 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.</p>
<p>For more information on the <tt>test-suite</tt> Makefile setup, please see
the <a href="TestSuiteMakefileGuide.html">Test Suite Makefile Guide.</a></p>
</div>
<!-- *********************************************************************** -->
<hr>
<address>
<a href="http://jigsaw.w3.org/css-validator/check/referer"><img
src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
<a href="http://validator.w3.org/check/referer"><img
src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
John T. Criswell, Daniel Dunbar, Reid Spencer, and Tanya Lattner<br>
<a href="http://llvm.org/">The LLVM Compiler Infrastructure</a><br>
Last modified: $Date: 2012-03-27 13:25:16 +0200 (Tue, 27 Mar 2012) $
</address>
</body>
</html>
|
