1FILECHECK(1) LLVM FILECHECK(1)
2
6 FileCheck - Flexible pattern matching file verifier
7
9 FileCheck match-filename [--check-prefix=XXX] [--strict-whitespace]
10
12 FileCheck reads two files (one from standard input, and one specified
13 on the command line) and uses one to verify the other. This behavior
14 is particularly useful for the testsuite, which wants to verify that
15 the output of some tool (e.g. llc) contains the expected information
16 (for example, a movsd from esp or whatever is interesting). This is
17 similar to using grep, but it is optimized for matching multiple dif‐
18 ferent inputs in one file in a specific order.
19 The match-filename file specifies the file that contains the patterns
21 to match. The file to verify is read from standard input unless the
22 --input-file option is used.
23
25 Options are parsed from the environment variable FILECHECK_OPTS and
26 from the command line.
27 -help Print a summary of command line options.
29 --check-prefix prefix
31 FileCheck searches the contents of match-filename for patterns
32 to match. By default, these patterns are prefixed with
33 "CHECK:". If you'd like to use a different prefix (e.g. because
34 the same input file is checking multiple different tool or op‐
35 tions), the --check-prefix argument allows you to specify (with‐
36 out the trailing ":") one or more prefixes to match. Multiple
37 prefixes are useful for tests which might change for different
38 run options, but most lines remain the same.
39 FileCheck does not permit duplicate prefixes, even if one is a
41 check prefix and one is a comment prefix (see --comment-prefixes
42 below).
43 --check-prefixes prefix1,prefix2,...
45 An alias of --check-prefix that allows multiple prefixes to be
46 specified as a comma separated list.
47 --comment-prefixes prefix1,prefix2,...
49 By default, FileCheck ignores any occurrence in match-filename
50 of any check prefix if it is preceded on the same line by "COM:"
51 or "RUN:". See the section The "COM:" directive for usage de‐
52 tails.
53 These default comment prefixes can be overridden by
55 --comment-prefixes if they are not appropriate for your testing
56 environment. However, doing so is not recommended in LLVM's
57 LIT-based test suites, which should be easier to maintain if
58 they all follow a consistent comment style. In that case, con‐
59 sider proposing a change to the default comment prefixes in‐
60 stead.
61 --allow-unused-prefixes
63 This option controls the behavior when using more than one pre‐
64 fix as specified by --check-prefix or --check-prefixes, and some
65 of these prefixes are missing in the test file. If true, this is
66 allowed, if false, FileCheck will report an error, listing the
67 missing prefixes.
68 It is currently, temporarily, true by default, and will be sub‐
70 sequently switched to false.
71 --input-file filename
73 File to check (defaults to stdin).
74 --match-full-lines
76 By default, FileCheck allows matches of anywhere on a line. This
77 option will require all positive matches to cover an entire
78 line. Leading and trailing whitespace is ignored, unless
79 --strict-whitespace is also specified. (Note: negative matches
80 from CHECK-NOT are not affected by this option!)
81 Passing this option is equivalent to inserting {{^ *}} or {{^}}
83 before, and {{ *$}} or {{$}} after every positive check pattern.
84 --strict-whitespace
86 By default, FileCheck canonicalizes input horizontal whitespace
87 (spaces and tabs) which causes it to ignore these differences (a
88 space will match a tab). The --strict-whitespace argument dis‐
89 ables this behavior. End-of-line sequences are canonicalized to
90 UNIX-style \n in all modes.
91 --ignore-case
93 By default, FileCheck uses case-sensitive matching. This option
94 causes FileCheck to use case-insensitive matching.
95 --implicit-check-not check-pattern
97 Adds implicit negative checks for the specified patterns between
98 positive checks. The option allows writing stricter tests with‐
99 out stuffing them with CHECK-NOTs.
100 For example, "--implicit-check-not warning:" can be useful when
102 testing diagnostic messages from tools that don't have an option
103 similar to clang -verify. With this option FileCheck will verify
104 that input does not contain warnings not covered by any CHECK:
105 patterns.
106 --dump-input <value>
108 Dump input to stderr, adding annotations representing currently
109 enabled diagnostics. When there are multiple occurrences of
110 this option, the <value> that appears earliest in the list below
111 has precedence. The default is fail.
112 • help - Explain input dump and quit
114 • always - Always dump input
116 • fail - Dump input on failure
118 • never - Never dump input
120 --dump-input-context <N>
122 In the dump requested by --dump-input, print <N> input lines be‐
123 fore and <N> input lines after any lines specified by --dump-in‐
124 put-filter. When there are multiple occurrences of this option,
125 the largest specified <N> has precedence. The default is 5.
126 --dump-input-filter <value>
128 In the dump requested by --dump-input, print only input lines of
129 kind <value> plus any context specified by --dump-input-context.
130 When there are multiple occurrences of this option, the <value>
131 that appears earliest in the list below has precedence. The de‐
132 fault is error when --dump-input=fail, and it's all when
133 --dump-input=always.
134 • all - All input lines
136 • annotation-full - Input lines with annotations
138 • annotation - Input lines with starting points of annota‐
140 tions
141 • error - Input lines with starting points of error
143 annotations
144 --enable-var-scope
146 Enables scope for regex variables.
147 Variables with names that start with $ are considered global and
149 remain set throughout the file.
150 All other variables get undefined after each encountered
152 CHECK-LABEL.
153 -D<VAR=VALUE>
155 Sets a filecheck pattern variable VAR with value VALUE that can
156 be used in CHECK: lines.
157 -D#<FMT>,<NUMVAR>=<NUMERIC EXPRESSION>
159 Sets a filecheck numeric variable NUMVAR of matching format FMT
160 to the result of evaluating <NUMERIC EXPRESSION> that can be
161 used in CHECK: lines. See section FileCheck Numeric Variables
162 and Expressions for details on supported numeric expressions.
163 -version
165 Show the version number of this program.
166 -v Print good directive pattern matches. However, if -dump-in‐
168 put=fail or -dump-input=always, add those matches as input anno‐
169 tations instead.
170 -vv Print information helpful in diagnosing internal FileCheck is‐
172 sues, such as discarded overlapping CHECK-DAG: matches, implicit
173 EOF pattern matches, and CHECK-NOT: patterns that do not have
174 matches. Implies -v. However, if -dump-input=fail or -dump-in‐
175 put=always, just add that information as input annotations in‐
176 stead.
177 --allow-deprecated-dag-overlap
179 Enable overlapping among matches in a group of consecutive
180 CHECK-DAG: directives. This option is deprecated and is only
181 provided for convenience as old tests are migrated to the new
182 non-overlapping CHECK-DAG: implementation.
183 --allow-empty
185 Allow checking empty input. By default, empty input is rejected.
186 --color
188 Use colors in output (autodetected by default).
189
191 If FileCheck verifies that the file matches the expected contents, it
192 exits with 0. Otherwise, if not, or if an error occurs, it will exit
193 with a non-zero value.
194
196 FileCheck is typically used from LLVM regression tests, being invoked
197 on the RUN line of the test. A simple example of using FileCheck from
198 a RUN line looks like this:
199 ; RUN: llvm-as < %s | llc -march=x86-64 | FileCheck %s
201 This syntax says to pipe the current file ("%s") into llvm-as, pipe
203 that into llc, then pipe the output of llc into FileCheck. This means
204 that FileCheck will be verifying its standard input (the llc output)
205 against the filename argument specified (the original .ll file speci‐
206 fied by "%s"). To see how this works, let's look at the rest of the
207 .ll file (after the RUN line):
208 define void @sub1(i32* %p, i32 %v) {
210 entry:
211 ; CHECK: sub1:
212 ; CHECK: subl
213 %0 = tail call i32 @llvm.atomic.load.sub.i32.p0i32(i32* %p, i32 %v)
214 ret void
215 }
216 define void @inc4(i64* %p) {
218 entry:
219 ; CHECK: inc4:
220 ; CHECK: incq
221 %0 = tail call i64 @llvm.atomic.load.add.i64.p0i64(i64* %p, i64 1)
222 ret void
223 }
224 Here you can see some "CHECK:" lines specified in comments. Now you
226 can see how the file is piped into llvm-as, then llc, and the machine
227 code output is what we are verifying. FileCheck checks the machine
228 code output to verify that it matches what the "CHECK:" lines specify.
229 The syntax of the "CHECK:" lines is very simple: they are fixed strings
231 that must occur in order. FileCheck defaults to ignoring horizontal
232 whitespace differences (e.g. a space is allowed to match a tab) but
233 otherwise, the contents of the "CHECK:" line is required to match some
234 thing in the test file exactly.
235 One nice thing about FileCheck (compared to grep) is that it allows
237 merging test cases together into logical groups. For example, because
238 the test above is checking for the "sub1:" and "inc4:" labels, it will
239 not match unless there is a "subl" in between those labels. If it ex‐
240 isted somewhere else in the file, that would not count: "grep subl"
241 matches if "subl" exists anywhere in the file.
242 The FileCheck -check-prefix option
244 The FileCheck -check-prefix option allows multiple test configurations
245 to be driven from one .ll file. This is useful in many circumstances,
246 for example, testing different architectural variants with llc. Here's
247 a simple example:
248 ; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin9 -mattr=sse41 \
250 ; RUN: | FileCheck %s -check-prefix=X32
251 ; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 -mattr=sse41 \
252 ; RUN: | FileCheck %s -check-prefix=X64
253 define <4 x i32> @pinsrd_1(i32 %s, <4 x i32> %tmp) nounwind {
255 %tmp1 = insertelement <4 x i32>; %tmp, i32 %s, i32 1
256 ret <4 x i32> %tmp1
257 ; X32: pinsrd_1:
258 ; X32: pinsrd $1, 4(%esp), %xmm0
259 ; X64: pinsrd_1:
261 ; X64: pinsrd $1, %edi, %xmm0
262 }
263 In this case, we're testing that we get the expected code generation
265 with both 32-bit and 64-bit code generation.
266 The "COM:" directive
268 Sometimes you want to disable a FileCheck directive without removing it
269 entirely, or you want to write comments that mention a directive by
270 name. The "COM:" directive makes it easy to do this. For example, you
271 might have:
272 ; X32: pinsrd_1:
274 ; X32: pinsrd $1, 4(%esp), %xmm0
275 ; COM: FIXME: X64 isn't working correctly yet for this part of codegen, but
277 ; COM: X64 will have something similar to X32:
278 ; COM:
279 ; COM: X64: pinsrd_1:
280 ; COM: X64: pinsrd $1, %edi, %xmm0
281 Without "COM:", you would need to use some combination of rewording and
283 directive syntax mangling to prevent FileCheck from recognizing the
284 commented occurrences of "X32:" and "X64:" above as directives. More‐
285 over, FileCheck diagnostics have been proposed that might complain
286 about the above occurrences of "X64" that don't have the trailing ":"
287 because they look like directive typos. Dodging all these problems can
288 be tedious for a test author, and directive syntax mangling can make
289 the purpose of test code unclear. "COM:" avoids all these problems.
290 A few important usage notes:
292 • "COM:" within another directive's pattern does not comment out the
294 remainder of the pattern. For example:
295 ; X32: pinsrd $1, 4(%esp), %xmm0 COM: This is part of the X32 pattern!
297 If you need to temporarily comment out part of a directive's pattern,
299 move it to another line. The reason is that FileCheck parses "COM:"
300 in the same manner as any other directive: only the first directive
301 on the line is recognized as a directive.
302 • For the sake of LIT, FileCheck treats "RUN:" just like "COM:". If
304 this is not suitable for your test environment, see
305 --comment-prefixes.
306 • FileCheck does not recognize "COM", "RUN", or any user-defined com‐
308 ment prefix as a comment directive if it's combined with one of the
309 usual check directive suffixes, such as "-NEXT:" or "-NOT:", dis‐
310 cussed below. FileCheck treats such a combination as plain text in‐
311 stead. If it needs to act as a comment directive for your test envi‐
312 ronment, define it as such with --comment-prefixes.
313 The "CHECK-NEXT:" directive
315 Sometimes you want to match lines and would like to verify that matches
316 happen on exactly consecutive lines with no other lines in between
317 them. In this case, you can use "CHECK:" and "CHECK-NEXT:" directives
318 to specify this. If you specified a custom check prefix, just use
319 "<PREFIX>-NEXT:". For example, something like this works as you'd ex‐
320 pect:
321 define void @t2(<2 x double>* %r, <2 x double>* %A, double %B) {
323 %tmp3 = load <2 x double>* %A, align 16
324 %tmp7 = insertelement <2 x double> undef, double %B, i32 0
325 %tmp9 = shufflevector <2 x double> %tmp3,
326 <2 x double> %tmp7,
327 <2 x i32> < i32 0, i32 2 >
328 store <2 x double> %tmp9, <2 x double>* %r, align 16
329 ret void
330 ; CHECK: t2:
332 ; CHECK: movl 8(%esp), %eax
333 ; CHECK-NEXT: movapd (%eax), %xmm0
334 ; CHECK-NEXT: movhpd 12(%esp), %xmm0
335 ; CHECK-NEXT: movl 4(%esp), %eax
336 ; CHECK-NEXT: movapd %xmm0, (%eax)
337 ; CHECK-NEXT: ret
338 }
339 "CHECK-NEXT:" directives reject the input unless there is exactly one
341 newline between it and the previous directive. A "CHECK-NEXT:" cannot
342 be the first directive in a file.
343 The "CHECK-SAME:" directive
345 Sometimes you want to match lines and would like to verify that matches
346 happen on the same line as the previous match. In this case, you can
347 use "CHECK:" and "CHECK-SAME:" directives to specify this. If you
348 specified a custom check prefix, just use "<PREFIX>-SAME:".
349 "CHECK-SAME:" is particularly powerful in conjunction with "CHECK-NOT:"
351 (described below).
352 For example, the following works like you'd expect:
354 !0 = !DILocation(line: 5, scope: !1, inlinedAt: !2)
356 ; CHECK: !DILocation(line: 5,
358 ; CHECK-NOT: column:
359 ; CHECK-SAME: scope: ![[SCOPE:[0-9]+]]
360 "CHECK-SAME:" directives reject the input if there are any newlines be‐
362 tween it and the previous directive.
363 "CHECK-SAME:" is also useful to avoid writing matchers for irrelevant
365 fields. For example, suppose you're writing a test which parses a tool
366 that generates output like this:
367 Name: foo
369 Field1: ...
370 Field2: ...
371 Field3: ...
372 Value: 1
373 Name: bar
375 Field1: ...
376 Field2: ...
377 Field3: ...
378 Value: 2
379 Name: baz
381 Field1: ...
382 Field2: ...
383 Field3: ...
384 Value: 1
385 To write a test that verifies foo has the value 1, you might first
387 write this:
388 CHECK: Name: foo
390 CHECK: Value: 1{{$}}
391 However, this would be a bad test: if the value for foo changes, the
393 test would still pass because the "CHECK: Value: 1" line would match
394 the value from baz. To fix this, you could add CHECK-NEXT matchers for
395 every FieldN: line, but that would be verbose, and need to be updated
396 when Field4 is added. A more succint way to write the test using the
397 "CHECK-SAME:" matcher would be as follows:
398 CHECK: Name: foo
400 CHECK: Value:
401 CHECK-SAME: {{ 1$}}
402 This verifies that the next time "Value:" appears in the output, it has
404 the value 1.
405 Note: a "CHECK-SAME:" cannot be the first directive in a file.
407 The "CHECK-EMPTY:" directive
409 If you need to check that the next line has nothing on it, not even
410 whitespace, you can use the "CHECK-EMPTY:" directive.
411 declare void @foo()
413 declare void @bar()
415 ; CHECK: foo
416 ; CHECK-EMPTY:
417 ; CHECK-NEXT: bar
418 Just like "CHECK-NEXT:" the directive will fail if there is more than
420 one newline before it finds the next blank line, and it cannot be the
421 first directive in a file.
422 The "CHECK-NOT:" directive
424 The "CHECK-NOT:" directive is used to verify that a string doesn't oc‐
425 cur between two matches (or before the first match, or after the last
426 match). For example, to verify that a load is removed by a transforma‐
427 tion, a test like this can be used:
428 define i8 @coerce_offset0(i32 %V, i32* %P) {
430 store i32 %V, i32* %P
431 %P2 = bitcast i32* %P to i8*
433 %P3 = getelementptr i8* %P2, i32 2
434 %A = load i8* %P3
436 ret i8 %A
437 ; CHECK: @coerce_offset0
438 ; CHECK-NOT: load
439 ; CHECK: ret i8
440 }
441 The "CHECK-COUNT:" directive
443 If you need to match multiple lines with the same pattern over and over
444 again you can repeat a plain CHECK: as many times as needed. If that
445 looks too boring you can instead use a counted check
446 "CHECK-COUNT-<num>:", where <num> is a positive decimal number. It will
447 match the pattern exactly <num> times, no more and no less. If you
448 specified a custom check prefix, just use "<PREFIX>-COUNT-<num>:" for
449 the same effect. Here is a simple example:
450 Loop at depth 1
452 Loop at depth 1
453 Loop at depth 1
454 Loop at depth 1
455 Loop at depth 2
456 Loop at depth 3
457 ; CHECK-COUNT-6: Loop at depth {{[0-9]+}}
459 ; CHECK-NOT: Loop at depth {{[0-9]+}}
460 The "CHECK-DAG:" directive
462 If it's necessary to match strings that don't occur in a strictly se‐
463 quential order, "CHECK-DAG:" could be used to verify them between two
464 matches (or before the first match, or after the last match). For exam‐
465 ple, clang emits vtable globals in reverse order. Using CHECK-DAG:, we
466 can keep the checks in the natural order:
467 // RUN: %clang_cc1 %s -emit-llvm -o - | FileCheck %s
469 struct Foo { virtual void method(); };
471 Foo f; // emit vtable
472 // CHECK-DAG: @_ZTV3Foo =
473 struct Bar { virtual void method(); };
475 Bar b;
476 // CHECK-DAG: @_ZTV3Bar =
477 CHECK-NOT: directives could be mixed with CHECK-DAG: directives to ex‐
479 clude strings between the surrounding CHECK-DAG: directives. As a re‐
480 sult, the surrounding CHECK-DAG: directives cannot be reordered, i.e.
481 all occurrences matching CHECK-DAG: before CHECK-NOT: must not fall be‐
482 hind occurrences matching CHECK-DAG: after CHECK-NOT:. For example,
483 ; CHECK-DAG: BEFORE
485 ; CHECK-NOT: NOT
486 ; CHECK-DAG: AFTER
487 This case will reject input strings where BEFORE occurs after AFTER.
489 With captured variables, CHECK-DAG: is able to match valid topological
491 orderings of a DAG with edges from the definition of a variable to its
492 use. It's useful, e.g., when your test cases need to match different
493 output sequences from the instruction scheduler. For example,
494 ; CHECK-DAG: add [[REG1:r[0-9]+]], r1, r2
496 ; CHECK-DAG: add [[REG2:r[0-9]+]], r3, r4
497 ; CHECK: mul r5, [[REG1]], [[REG2]]
498 In this case, any order of that two add instructions will be allowed.
500 If you are defining and using variables in the same CHECK-DAG: block,
502 be aware that the definition rule can match after its use.
503 So, for instance, the code below will pass:
505 ; CHECK-DAG: vmov.32 [[REG2:d[0-9]+]][0]
507 ; CHECK-DAG: vmov.32 [[REG2]][1]
508 vmov.32 d0[1]
509 vmov.32 d0[0]
510 While this other code, will not:
512 ; CHECK-DAG: vmov.32 [[REG2:d[0-9]+]][0]
514 ; CHECK-DAG: vmov.32 [[REG2]][1]
515 vmov.32 d1[1]
516 vmov.32 d0[0]
517 While this can be very useful, it's also dangerous, because in the case
519 of register sequence, you must have a strong order (read before write,
520 copy before use, etc). If the definition your test is looking for
521 doesn't match (because of a bug in the compiler), it may match further
522 away from the use, and mask real bugs away.
523 In those cases, to enforce the order, use a non-DAG directive between
525 DAG-blocks.
526 A CHECK-DAG: directive skips matches that overlap the matches of any
528 preceding CHECK-DAG: directives in the same CHECK-DAG: block. Not only
529 is this non-overlapping behavior consistent with other directives, but
530 it's also necessary to handle sets of non-unique strings or patterns.
531 For example, the following directives look for unordered log entries
532 for two tasks in a parallel program, such as the OpenMP runtime:
533 // CHECK-DAG: [[THREAD_ID:[0-9]+]]: task_begin
535 // CHECK-DAG: [[THREAD_ID]]: task_end
536 //
537 // CHECK-DAG: [[THREAD_ID:[0-9]+]]: task_begin
538 // CHECK-DAG: [[THREAD_ID]]: task_end
539 The second pair of directives is guaranteed not to match the same log
541 entries as the first pair even though the patterns are identical and
542 even if the text of the log entries is identical because the thread ID
543 manages to be reused.
544 The "CHECK-LABEL:" directive
546 Sometimes in a file containing multiple tests divided into logical
547 blocks, one or more CHECK: directives may inadvertently succeed by
548 matching lines in a later block. While an error will usually eventually
549 be generated, the check flagged as causing the error may not actually
550 bear any relationship to the actual source of the problem.
551 In order to produce better error messages in these cases, the
553 "CHECK-LABEL:" directive can be used. It is treated identically to a
554 normal CHECK directive except that FileCheck makes an additional as‐
555 sumption that a line matched by the directive cannot also be matched by
556 any other check present in match-filename; this is intended to be used
557 for lines containing labels or other unique identifiers. Conceptually,
558 the presence of CHECK-LABEL divides the input stream into separate
559 blocks, each of which is processed independently, preventing a CHECK:
560 directive in one block matching a line in another block. If --en‐
561 able-var-scope is in effect, all local variables are cleared at the be‐
562 ginning of the block.
563 For example,
565 define %struct.C* @C_ctor_base(%struct.C* %this, i32 %x) {
567 entry:
568 ; CHECK-LABEL: C_ctor_base:
569 ; CHECK: mov [[SAVETHIS:r[0-9]+]], r0
570 ; CHECK: bl A_ctor_base
571 ; CHECK: mov r0, [[SAVETHIS]]
572 %0 = bitcast %struct.C* %this to %struct.A*
573 %call = tail call %struct.A* @A_ctor_base(%struct.A* %0)
574 %1 = bitcast %struct.C* %this to %struct.B*
575 %call2 = tail call %struct.B* @B_ctor_base(%struct.B* %1, i32 %x)
576 ret %struct.C* %this
577 }
578 define %struct.D* @D_ctor_base(%struct.D* %this, i32 %x) {
580 entry:
581 ; CHECK-LABEL: D_ctor_base:
582 The use of CHECK-LABEL: directives in this case ensures that the three
584 CHECK: directives only accept lines corresponding to the body of the
585 @C_ctor_base function, even if the patterns match lines found later in
586 the file. Furthermore, if one of these three CHECK: directives fail,
587 FileCheck will recover by continuing to the next block, allowing multi‐
588 ple test failures to be detected in a single invocation.
589 There is no requirement that CHECK-LABEL: directives contain strings
591 that correspond to actual syntactic labels in a source or output lan‐
592 guage: they must simply uniquely match a single line in the file being
593 verified.
594 CHECK-LABEL: directives cannot contain variable definitions or uses.
596 Directive modifiers
598 A directive modifier can be append to a directive by following the di‐
599 rective with {<modifier>} where the only supported value for <modifier>
600 is LITERAL.
601 The LITERAL directive modifier can be used to perform a literal match.
603 The modifier results in the directive not recognizing any syntax to
604 perform regex matching, variable capture or any substitutions. This is
605 useful when the text to match would require excessive escaping other‐
606 wise. For example, the following will perform literal matches rather
607 than considering these as regular expressions:
608 Input: [[[10, 20]], [[30, 40]]]
610 Output %r10: [[10, 20]]
611 Output %r10: [[30, 40]]
612 ; CHECK{LITERAL}: [[[10, 20]], [[30, 40]]]
614 ; CHECK-DAG{LITERAL}: [[30, 40]]
615 ; CHECK-DAG{LITERAL}: [[10, 20]]
616 FileCheck Regex Matching Syntax
618 All FileCheck directives take a pattern to match. For most uses of
619 FileCheck, fixed string matching is perfectly sufficient. For some
620 things, a more flexible form of matching is desired. To support this,
621 FileCheck allows you to specify regular expressions in matching
622 strings, surrounded by double braces: {{yourregex}}. FileCheck imple‐
623 ments a POSIX regular expression matcher; it supports Extended POSIX
624 regular expressions (ERE). Because we want to use fixed string matching
625 for a majority of what we do, FileCheck has been designed to support
626 mixing and matching fixed string matching with regular expressions.
627 This allows you to write things like this:
628 ; CHECK: movhpd {{[0-9]+}}(%esp), {{%xmm[0-7]}}
630 In this case, any offset from the ESP register will be allowed, and any
632 xmm register will be allowed.
633 Because regular expressions are enclosed with double braces, they are
635 visually distinct, and you don't need to use escape characters within
636 the double braces like you would in C. In the rare case that you want
637 to match double braces explicitly from the input, you can use something
638 ugly like {{[}][}]}} as your pattern. Or if you are using the repeti‐
639 tion count syntax, for example [[:xdigit:]]{8} to match exactly 8 hex
640 digits, you would need to add parentheses like this
641 {{([[:xdigit:]]{8})}} to avoid confusion with FileCheck's closing dou‐
642 ble-brace.
643 FileCheck String Substitution Blocks
645 It is often useful to match a pattern and then verify that it occurs
646 again later in the file. For codegen tests, this can be useful to al‐
647 low any register, but verify that that register is used consistently
648 later. To do this, FileCheck supports string substitution blocks that
649 allow string variables to be defined and substituted into patterns.
650 Here is a simple example:
651 ; CHECK: test5:
653 ; CHECK: notw [[REGISTER:%[a-z]+]]
654 ; CHECK: andw {{.*}}[[REGISTER]]
655 The first check line matches a regex %[a-z]+ and captures it into the
657 string variable REGISTER. The second line verifies that whatever is in
658 REGISTER occurs later in the file after an "andw". FileCheck string
659 substitution blocks are always contained in [[ ]] pairs, and string
660 variable names can be formed with the regex [a-zA-Z_][a-zA-Z0-9_]*. If
661 a colon follows the name, then it is a definition of the variable; oth‐
662 erwise, it is a substitution.
663 FileCheck variables can be defined multiple times, and substitutions
665 always get the latest value. Variables can also be substituted later
666 on the same line they were defined on. For example:
667 ; CHECK: op [[REG:r[0-9]+]], [[REG]]
669 Can be useful if you want the operands of op to be the same register,
671 and don't care exactly which register it is.
672 If --enable-var-scope is in effect, variables with names that start
674 with $ are considered to be global. All others variables are local.
675 All local variables get undefined at the beginning of each CHECK-LABEL
676 block. Global variables are not affected by CHECK-LABEL. This makes it
677 easier to ensure that individual tests are not affected by variables
678 set in preceding tests.
679 FileCheck Numeric Substitution Blocks
681 FileCheck also supports numeric substitution blocks that allow defining
682 numeric variables and checking for numeric values that satisfy a nu‐
683 meric expression constraint based on those variables via a numeric sub‐
684 stitution. This allows CHECK: directives to verify a numeric relation
685 between two numbers, such as the need for consecutive registers to be
686 used.
687 The syntax to capture a numeric value is [[#%<fmtspec>,<NUMVAR>:]]
689 where:
690 • %<fmtspec>, is an optional format specifier to indicate what number
692 format to match and the minimum number of digits to expect.
693 • <NUMVAR>: is an optional definition of variable <NUMVAR> from the
695 captured value.
696 The syntax of <fmtspec> is: #.<precision><conversion specifier> where:
698 • # is an optional flag available for hex values (see <conversion spec‐
700 ifier> below) which requires the value matched to be prefixed by 0x.
701 • .<precision> is an optional printf-style precision specifier in which
703 <precision> indicates the minimum number of digits that the value
704 matched must have, expecting leading zeros if needed.
705 • <conversion specifier> is an optional scanf-style conversion speci‐
707 fier to indicate what number format to match (e.g. hex number). Cur‐
708 rently accepted format specifiers are %u, %d, %x and %X. If absent,
709 the format specifier defaults to %u.
710 For example:
712 ; CHECK: mov r[[#REG:]], 0x[[#%.8X,ADDR:]]
714 would match mov r5, 0x0000FEFE and set REG to the value 5 and ADDR to
716 the value 0xFEFE. Note that due to the precision it would fail to match
717 mov r5, 0xFEFE.
718 As a result of the numeric variable definition being optional, it is
720 possible to only check that a numeric value is present in a given for‐
721 mat. This can be useful when the value itself is not useful, for in‐
722 stance:
723 ; CHECK-NOT: mov r0, r[[#]]
725 to check that a value is synthesized rather than moved around.
727 The syntax of a numeric substitution is [[#%<fmtspec>, <constraint>
729 <expr>]] where:
730 • <fmtspec> is the same format specifier as for defining a variable but
732 in this context indicating how a numeric expression value should be
733 matched against. If absent, both components of the format specifier
734 are inferred from the matching format of the numeric variable(s) used
735 by the expression constraint if any, and defaults to %u if no numeric
736 variable is used, denoting that the value should be unsigned with no
737 leading zeros. In case of conflict between format specifiers of sev‐
738 eral numeric variables, the conversion specifier becomes mandatory
739 but the precision specifier remains optional.
740 • <constraint> is the constraint describing how the value to match must
742 relate to the value of the numeric expression. The only currently ac‐
743 cepted constraint is == for an exact match and is the default if
744 <constraint> is not provided. No matching constraint must be speci‐
745 fied when the <expr> is empty.
746 • <expr> is an expression. An expression is in turn recursively defined
748 as:
749 • a numeric operand, or
751 • an expression followed by an operator and a numeric operand.
753 A numeric operand is a previously defined numeric variable, an inte‐
755 ger literal, or a function. Spaces are accepted before, after and be‐
756 tween any of these elements. Numeric operands have 64-bit precision.
757 Overflow and underflow are rejected. There is no support for operator
758 precedence, but parentheses can be used to change the evaluation or‐
759 der.
760 The supported operators are:
762 • + - Returns the sum of its two operands.
764 • - - Returns the difference of its two operands.
766 The syntax of a function call is <name>(<arguments>) where:
768 • name is a predefined string literal. Accepted values are:
770 • add - Returns the sum of its two operands.
772 • div - Returns the quotient of its two operands.
774 • max - Returns the largest of its two operands.
776 • min - Returns the smallest of its two operands.
778 • mul - Returns the product of its two operands.
780 • sub - Returns the difference of its two operands.
782 • <arguments> is a comma separated list of expressions.
784 For example:
786 ; CHECK: load r[[#REG:]], [r0]
788 ; CHECK: load r[[#REG+1]], [r1]
789 ; CHECK: Loading from 0x[[#%x,ADDR:]]
790 ; CHECK-SAME: to 0x[[#ADDR + 7]]
791 The above example would match the text:
793 load r5, [r0]
795 load r6, [r1]
796 Loading from 0xa0463440 to 0xa0463447
797 but would not match the text:
799 load r5, [r0]
801 load r7, [r1]
802 Loading from 0xa0463440 to 0xa0463443
803 Due to 7 being unequal to 5 + 1 and a0463443 being unequal to a0463440
805 + 7.
806 A numeric variable can also be defined to the result of a numeric ex‐
808 pression, in which case the numeric expression constraint is checked
809 and if verified the variable is assigned to the value. The unified syn‐
810 tax for both checking a numeric expression and capturing its value into
811 a numeric variable is thus [[#%<fmtspec>,<NUMVAR>: <constraint>
812 <expr>]] with each element as described previously. One can use this
813 syntax to make a testcase more self-describing by using variables in‐
814 stead of values:
815 ; CHECK: mov r[[#REG_OFFSET:]], 0x[[#%X,FIELD_OFFSET:12]]
817 ; CHECK-NEXT: load r[[#]], [r[[#REG_BASE:]], r[[#REG_OFFSET]]]
818 which would match:
820 mov r4, 0xC
822 load r6, [r5, r4]
823 The --enable-var-scope option has the same effect on numeric variables
825 as on string variables.
826 Important note: In its current implementation, an expression cannot use
828 a numeric variable defined earlier in the same CHECK directive.
829 FileCheck Pseudo Numeric Variables
831 Sometimes there's a need to verify output that contains line numbers of
832 the match file, e.g. when testing compiler diagnostics. This intro‐
833 duces a certain fragility of the match file structure, as "CHECK:"
834 lines contain absolute line numbers in the same file, which have to be
835 updated whenever line numbers change due to text addition or deletion.
836 To support this case, FileCheck expressions understand the @LINE pseudo
838 numeric variable which evaluates to the line number of the CHECK pat‐
839 tern where it is found.
840 This way match patterns can be put near the relevant test lines and in‐
842 clude relative line number references, for example:
843 // CHECK: test.cpp:[[# @LINE + 4]]:6: error: expected ';' after top level declarator
845 // CHECK-NEXT: {{^int a}}
846 // CHECK-NEXT: {{^ \^}}
847 // CHECK-NEXT: {{^ ;}}
848 int a
849 To support legacy uses of @LINE as a special string variable, FileCheck
851 also accepts the following uses of @LINE with string substitution block
852 syntax: [[@LINE]], [[@LINE+<offset>]] and [[@LINE-<offset>]] without
853 any spaces inside the brackets and where offset is an integer.
854 Matching Newline Characters
856 To match newline characters in regular expressions the character class
857 [[:space:]] can be used. For example, the following pattern:
858 // CHECK: DW_AT_location [DW_FORM_sec_offset] ([[DLOC:0x[0-9a-f]+]]){{[[:space:]].*}}"intd"
860 matches output of the form (from llvm-dwarfdump):
862 DW_AT_location [DW_FORM_sec_offset] (0x00000233)
864 DW_AT_name [DW_FORM_strp] ( .debug_str[0x000000c9] = "intd")
865 letting us set the FileCheck variable DLOC to the desired value
867 0x00000233, extracted from the line immediately preceding "intd".
868
870 Maintained by the LLVM Team (https://llvm.org/).
871
873 2003-2023, LLVM Project
87413 2023-07-20 FILECHECK(1)