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. The default value is false.
68 --input-file filename
70 File to check (defaults to stdin).
71 --match-full-lines
73 By default, FileCheck allows matches of anywhere on a line. This
74 option will require all positive matches to cover an entire
75 line. Leading and trailing whitespace is ignored, unless
76 --strict-whitespace is also specified. (Note: negative matches
77 from CHECK-NOT are not affected by this option!)
78 Passing this option is equivalent to inserting {{^ *}} or {{^}}
80 before, and {{ *$}} or {{$}} after every positive check pattern.
81 --strict-whitespace
83 By default, FileCheck canonicalizes input horizontal whitespace
84 (spaces and tabs) which causes it to ignore these differences (a
85 space will match a tab). The --strict-whitespace argument dis‐
86 ables this behavior. End-of-line sequences are canonicalized to
87 UNIX-style \n in all modes.
88 --ignore-case
90 By default, FileCheck uses case-sensitive matching. This option
91 causes FileCheck to use case-insensitive matching.
92 --implicit-check-not check-pattern
94 Adds implicit negative checks for the specified patterns between
95 positive checks. The option allows writing stricter tests with‐
96 out stuffing them with CHECK-NOTs.
97 For example, "--implicit-check-not warning:" can be useful when
99 testing diagnostic messages from tools that don't have an option
100 similar to clang -verify. With this option FileCheck will verify
101 that input does not contain warnings not covered by any CHECK:
102 patterns.
103 --dump-input <value>
105 Dump input to stderr, adding annotations representing currently
106 enabled diagnostics. When there are multiple occurrences of
107 this option, the <value> that appears earliest in the list below
108 has precedence. The default is fail.
109 • help - Explain input dump and quit
111 • always - Always dump input
113 • fail - Dump input on failure
115 • never - Never dump input
117 --dump-input-context <N>
119 In the dump requested by --dump-input, print <N> input lines be‐
120 fore and <N> input lines after any lines specified by --dump-in‐
121 put-filter. When there are multiple occurrences of this option,
122 the largest specified <N> has precedence. The default is 5.
123 --dump-input-filter <value>
125 In the dump requested by --dump-input, print only input lines of
126 kind <value> plus any context specified by --dump-input-context.
127 When there are multiple occurrences of this option, the <value>
128 that appears earliest in the list below has precedence. The de‐
129 fault is error when --dump-input=fail, and it's all when
130 --dump-input=always.
131 • all - All input lines
133 • annotation-full - Input lines with annotations
135 • annotation - Input lines with starting points of annota‐
137 tions
138 • error - Input lines with starting points of error
140 annotations
141 --enable-var-scope
143 Enables scope for regex variables.
144 Variables with names that start with $ are considered global and
146 remain set throughout the file.
147 All other variables get undefined after each encountered
149 CHECK-LABEL.
150 -D<VAR=VALUE>
152 Sets a filecheck pattern variable VAR with value VALUE that can
153 be used in CHECK: lines.
154 -D#<FMT>,<NUMVAR>=<NUMERIC EXPRESSION>
156 Sets a filecheck numeric variable NUMVAR of matching format FMT
157 to the result of evaluating <NUMERIC EXPRESSION> that can be
158 used in CHECK: lines. See section FileCheck Numeric Variables
159 and Expressions for details on supported numeric expressions.
160 -version
162 Show the version number of this program.
163 -v Print good directive pattern matches. However, if -dump-in‐
165 put=fail or -dump-input=always, add those matches as input anno‐
166 tations instead.
167 -vv Print information helpful in diagnosing internal FileCheck is‐
169 sues, such as discarded overlapping CHECK-DAG: matches, implicit
170 EOF pattern matches, and CHECK-NOT: patterns that do not have
171 matches. Implies -v. However, if -dump-input=fail or -dump-in‐
172 put=always, just add that information as input annotations in‐
173 stead.
174 --allow-deprecated-dag-overlap
176 Enable overlapping among matches in a group of consecutive
177 CHECK-DAG: directives. This option is deprecated and is only
178 provided for convenience as old tests are migrated to the new
179 non-overlapping CHECK-DAG: implementation.
180 --allow-empty
182 Allow checking empty input. By default, empty input is rejected.
183 --color
185 Use colors in output (autodetected by default).
186
188 If FileCheck verifies that the file matches the expected contents, it
189 exits with 0. Otherwise, if not, or if an error occurs, it will exit
190 with a non-zero value.
191
193 FileCheck is typically used from LLVM regression tests, being invoked
194 on the RUN line of the test. A simple example of using FileCheck from
195 a RUN line looks like this:
196 ; RUN: llvm-as < %s | llc -march=x86-64 | FileCheck %s
198 This syntax says to pipe the current file ("%s") into llvm-as, pipe
200 that into llc, then pipe the output of llc into FileCheck. This means
201 that FileCheck will be verifying its standard input (the llc output)
202 against the filename argument specified (the original .ll file speci‐
203 fied by "%s"). To see how this works, let's look at the rest of the
204 .ll file (after the RUN line):
205 define void @sub1(i32* %p, i32 %v) {
207 entry:
208 ; CHECK: sub1:
209 ; CHECK: subl
210 %0 = tail call i32 @llvm.atomic.load.sub.i32.p0i32(i32* %p, i32 %v)
211 ret void
212 }
213 define void @inc4(i64* %p) {
215 entry:
216 ; CHECK: inc4:
217 ; CHECK: incq
218 %0 = tail call i64 @llvm.atomic.load.add.i64.p0i64(i64* %p, i64 1)
219 ret void
220 }
221 Here you can see some "CHECK:" lines specified in comments. Now you
223 can see how the file is piped into llvm-as, then llc, and the machine
224 code output is what we are verifying. FileCheck checks the machine
225 code output to verify that it matches what the "CHECK:" lines specify.
226 The syntax of the "CHECK:" lines is very simple: they are fixed strings
228 that must occur in order. FileCheck defaults to ignoring horizontal
229 whitespace differences (e.g. a space is allowed to match a tab) but
230 otherwise, the contents of the "CHECK:" line is required to match some
231 thing in the test file exactly.
232 One nice thing about FileCheck (compared to grep) is that it allows
234 merging test cases together into logical groups. For example, because
235 the test above is checking for the "sub1:" and "inc4:" labels, it will
236 not match unless there is a "subl" in between those labels. If it ex‐
237 isted somewhere else in the file, that would not count: "grep subl"
238 matches if "subl" exists anywhere in the file.
239 The FileCheck -check-prefix option
241 The FileCheck -check-prefix option allows multiple test configurations
242 to be driven from one .ll file. This is useful in many circumstances,
243 for example, testing different architectural variants with llc. Here's
244 a simple example:
245 ; RUN: llvm-as < %s | llc -mtriple=i686-apple-darwin9 -mattr=sse41 \
247 ; RUN: | FileCheck %s -check-prefix=X32
248 ; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin9 -mattr=sse41 \
249 ; RUN: | FileCheck %s -check-prefix=X64
250 define <4 x i32> @pinsrd_1(i32 %s, <4 x i32> %tmp) nounwind {
252 %tmp1 = insertelement <4 x i32>; %tmp, i32 %s, i32 1
253 ret <4 x i32> %tmp1
254 ; X32: pinsrd_1:
255 ; X32: pinsrd $1, 4(%esp), %xmm0
256 ; X64: pinsrd_1:
258 ; X64: pinsrd $1, %edi, %xmm0
259 }
260 In this case, we're testing that we get the expected code generation
262 with both 32-bit and 64-bit code generation.
263 The "COM:" directive
265 Sometimes you want to disable a FileCheck directive without removing it
266 entirely, or you want to write comments that mention a directive by
267 name. The "COM:" directive makes it easy to do this. For example, you
268 might have:
269 ; X32: pinsrd_1:
271 ; X32: pinsrd $1, 4(%esp), %xmm0
272 ; COM: FIXME: X64 isn't working correctly yet for this part of codegen, but
274 ; COM: X64 will have something similar to X32:
275 ; COM:
276 ; COM: X64: pinsrd_1:
277 ; COM: X64: pinsrd $1, %edi, %xmm0
278 Without "COM:", you would need to use some combination of rewording and
280 directive syntax mangling to prevent FileCheck from recognizing the
281 commented occurrences of "X32:" and "X64:" above as directives. More‐
282 over, FileCheck diagnostics have been proposed that might complain
283 about the above occurrences of "X64" that don't have the trailing ":"
284 because they look like directive typos. Dodging all these problems can
285 be tedious for a test author, and directive syntax mangling can make
286 the purpose of test code unclear. "COM:" avoids all these problems.
287 A few important usage notes:
289 • "COM:" within another directive's pattern does not comment out the
291 remainder of the pattern. For example:
292 ; X32: pinsrd $1, 4(%esp), %xmm0 COM: This is part of the X32 pattern!
294 If you need to temporarily comment out part of a directive's pattern,
296 move it to another line. The reason is that FileCheck parses "COM:"
297 in the same manner as any other directive: only the first directive
298 on the line is recognized as a directive.
299 • For the sake of LIT, FileCheck treats "RUN:" just like "COM:". If
301 this is not suitable for your test environment, see
302 --comment-prefixes.
303 • FileCheck does not recognize "COM", "RUN", or any user-defined com‐
305 ment prefix as a comment directive if it's combined with one of the
306 usual check directive suffixes, such as "-NEXT:" or "-NOT:", dis‐
307 cussed below. FileCheck treats such a combination as plain text in‐
308 stead. If it needs to act as a comment directive for your test envi‐
309 ronment, define it as such with --comment-prefixes.
310 The "CHECK-NEXT:" directive
312 Sometimes you want to match lines and would like to verify that matches
313 happen on exactly consecutive lines with no other lines in between
314 them. In this case, you can use "CHECK:" and "CHECK-NEXT:" directives
315 to specify this. If you specified a custom check prefix, just use
316 "<PREFIX>-NEXT:". For example, something like this works as you'd ex‐
317 pect:
318 define void @t2(<2 x double>* %r, <2 x double>* %A, double %B) {
320 %tmp3 = load <2 x double>* %A, align 16
321 %tmp7 = insertelement <2 x double> undef, double %B, i32 0
322 %tmp9 = shufflevector <2 x double> %tmp3,
323 <2 x double> %tmp7,
324 <2 x i32> < i32 0, i32 2 >
325 store <2 x double> %tmp9, <2 x double>* %r, align 16
326 ret void
327 ; CHECK: t2:
329 ; CHECK: movl 8(%esp), %eax
330 ; CHECK-NEXT: movapd (%eax), %xmm0
331 ; CHECK-NEXT: movhpd 12(%esp), %xmm0
332 ; CHECK-NEXT: movl 4(%esp), %eax
333 ; CHECK-NEXT: movapd %xmm0, (%eax)
334 ; CHECK-NEXT: ret
335 }
336 "CHECK-NEXT:" directives reject the input unless there is exactly one
338 newline between it and the previous directive. A "CHECK-NEXT:" cannot
339 be the first directive in a file.
340 The "CHECK-SAME:" directive
342 Sometimes you want to match lines and would like to verify that matches
343 happen on the same line as the previous match. In this case, you can
344 use "CHECK:" and "CHECK-SAME:" directives to specify this. If you
345 specified a custom check prefix, just use "<PREFIX>-SAME:".
346 "CHECK-SAME:" is particularly powerful in conjunction with "CHECK-NOT:"
348 (described below).
349 For example, the following works like you'd expect:
351 !0 = !DILocation(line: 5, scope: !1, inlinedAt: !2)
353 ; CHECK: !DILocation(line: 5,
355 ; CHECK-NOT: column:
356 ; CHECK-SAME: scope: ![[SCOPE:[0-9]+]]
357 "CHECK-SAME:" directives reject the input if there are any newlines be‐
359 tween it and the previous directive.
360 "CHECK-SAME:" is also useful to avoid writing matchers for irrelevant
362 fields. For example, suppose you're writing a test which parses a tool
363 that generates output like this:
364 Name: foo
366 Field1: ...
367 Field2: ...
368 Field3: ...
369 Value: 1
370 Name: bar
372 Field1: ...
373 Field2: ...
374 Field3: ...
375 Value: 2
376 Name: baz
378 Field1: ...
379 Field2: ...
380 Field3: ...
381 Value: 1
382 To write a test that verifies foo has the value 1, you might first
384 write this:
385 CHECK: Name: foo
387 CHECK: Value: 1{{$}}
388 However, this would be a bad test: if the value for foo changes, the
390 test would still pass because the "CHECK: Value: 1" line would match
391 the value from baz. To fix this, you could add CHECK-NEXT matchers for
392 every FieldN: line, but that would be verbose, and need to be updated
393 when Field4 is added. A more succinct way to write the test using the
394 "CHECK-SAME:" matcher would be as follows:
395 CHECK: Name: foo
397 CHECK: Value:
398 CHECK-SAME: {{ 1$}}
399 This verifies that the next time "Value:" appears in the output, it has
401 the value 1.
402 Note: a "CHECK-SAME:" cannot be the first directive in a file.
404 The "CHECK-EMPTY:" directive
406 If you need to check that the next line has nothing on it, not even
407 whitespace, you can use the "CHECK-EMPTY:" directive.
408 declare void @foo()
410 declare void @bar()
412 ; CHECK: foo
413 ; CHECK-EMPTY:
414 ; CHECK-NEXT: bar
415 Just like "CHECK-NEXT:" the directive will fail if there is more than
417 one newline before it finds the next blank line, and it cannot be the
418 first directive in a file.
419 The "CHECK-NOT:" directive
421 The "CHECK-NOT:" directive is used to verify that a string doesn't oc‐
422 cur between two matches (or before the first match, or after the last
423 match). For example, to verify that a load is removed by a transforma‐
424 tion, a test like this can be used:
425 define i8 @coerce_offset0(i32 %V, i32* %P) {
427 store i32 %V, i32* %P
428 %P2 = bitcast i32* %P to i8*
430 %P3 = getelementptr i8* %P2, i32 2
431 %A = load i8* %P3
433 ret i8 %A
434 ; CHECK: @coerce_offset0
435 ; CHECK-NOT: load
436 ; CHECK: ret i8
437 }
438 The "CHECK-COUNT:" directive
440 If you need to match multiple lines with the same pattern over and over
441 again you can repeat a plain CHECK: as many times as needed. If that
442 looks too boring you can instead use a counted check
443 "CHECK-COUNT-<num>:", where <num> is a positive decimal number. It will
444 match the pattern exactly <num> times, no more and no less. If you
445 specified a custom check prefix, just use "<PREFIX>-COUNT-<num>:" for
446 the same effect. Here is a simple example:
447 Loop at depth 1
449 Loop at depth 1
450 Loop at depth 1
451 Loop at depth 1
452 Loop at depth 2
453 Loop at depth 3
454 ; CHECK-COUNT-6: Loop at depth {{[0-9]+}}
456 ; CHECK-NOT: Loop at depth {{[0-9]+}}
457 The "CHECK-DAG:" directive
459 If it's necessary to match strings that don't occur in a strictly se‐
460 quential order, "CHECK-DAG:" could be used to verify them between two
461 matches (or before the first match, or after the last match). For exam‐
462 ple, clang emits vtable globals in reverse order. Using CHECK-DAG:, we
463 can keep the checks in the natural order:
464 // RUN: %clang_cc1 %s -emit-llvm -o - | FileCheck %s
466 struct Foo { virtual void method(); };
468 Foo f; // emit vtable
469 // CHECK-DAG: @_ZTV3Foo =
470 struct Bar { virtual void method(); };
472 Bar b;
473 // CHECK-DAG: @_ZTV3Bar =
474 CHECK-NOT: directives could be mixed with CHECK-DAG: directives to ex‐
476 clude strings between the surrounding CHECK-DAG: directives. As a re‐
477 sult, the surrounding CHECK-DAG: directives cannot be reordered, i.e.
478 all occurrences matching CHECK-DAG: before CHECK-NOT: must not fall be‐
479 hind occurrences matching CHECK-DAG: after CHECK-NOT:. For example,
480 ; CHECK-DAG: BEFORE
482 ; CHECK-NOT: NOT
483 ; CHECK-DAG: AFTER
484 This case will reject input strings where BEFORE occurs after AFTER.
486 With captured variables, CHECK-DAG: is able to match valid topological
488 orderings of a DAG with edges from the definition of a variable to its
489 use. It's useful, e.g., when your test cases need to match different
490 output sequences from the instruction scheduler. For example,
491 ; CHECK-DAG: add [[REG1:r[0-9]+]], r1, r2
493 ; CHECK-DAG: add [[REG2:r[0-9]+]], r3, r4
494 ; CHECK: mul r5, [[REG1]], [[REG2]]
495 In this case, any order of that two add instructions will be allowed.
497 If you are defining and using variables in the same CHECK-DAG: block,
499 be aware that the definition rule can match after its use.
500 So, for instance, the code below will pass:
502 ; CHECK-DAG: vmov.32 [[REG2:d[0-9]+]][0]
504 ; CHECK-DAG: vmov.32 [[REG2]][1]
505 vmov.32 d0[1]
506 vmov.32 d0[0]
507 While this other code, will not:
509 ; CHECK-DAG: vmov.32 [[REG2:d[0-9]+]][0]
511 ; CHECK-DAG: vmov.32 [[REG2]][1]
512 vmov.32 d1[1]
513 vmov.32 d0[0]
514 While this can be very useful, it's also dangerous, because in the case
516 of register sequence, you must have a strong order (read before write,
517 copy before use, etc). If the definition your test is looking for
518 doesn't match (because of a bug in the compiler), it may match further
519 away from the use, and mask real bugs away.
520 In those cases, to enforce the order, use a non-DAG directive between
522 DAG-blocks.
523 A CHECK-DAG: directive skips matches that overlap the matches of any
525 preceding CHECK-DAG: directives in the same CHECK-DAG: block. Not only
526 is this non-overlapping behavior consistent with other directives, but
527 it's also necessary to handle sets of non-unique strings or patterns.
528 For example, the following directives look for unordered log entries
529 for two tasks in a parallel program, such as the OpenMP runtime:
530 // CHECK-DAG: [[THREAD_ID:[0-9]+]]: task_begin
532 // CHECK-DAG: [[THREAD_ID]]: task_end
533 //
534 // CHECK-DAG: [[THREAD_ID:[0-9]+]]: task_begin
535 // CHECK-DAG: [[THREAD_ID]]: task_end
536 The second pair of directives is guaranteed not to match the same log
538 entries as the first pair even though the patterns are identical and
539 even if the text of the log entries is identical because the thread ID
540 manages to be reused.
541 The "CHECK-LABEL:" directive
543 Sometimes in a file containing multiple tests divided into logical
544 blocks, one or more CHECK: directives may inadvertently succeed by
545 matching lines in a later block. While an error will usually eventually
546 be generated, the check flagged as causing the error may not actually
547 bear any relationship to the actual source of the problem.
548 In order to produce better error messages in these cases, the
550 "CHECK-LABEL:" directive can be used. It is treated identically to a
551 normal CHECK directive except that FileCheck makes an additional as‐
552 sumption that a line matched by the directive cannot also be matched by
553 any other check present in match-filename; this is intended to be used
554 for lines containing labels or other unique identifiers. Conceptually,
555 the presence of CHECK-LABEL divides the input stream into separate
556 blocks, each of which is processed independently, preventing a CHECK:
557 directive in one block matching a line in another block. If --en‐
558 able-var-scope is in effect, all local variables are cleared at the be‐
559 ginning of the block.
560 For example,
562 define %struct.C* @C_ctor_base(%struct.C* %this, i32 %x) {
564 entry:
565 ; CHECK-LABEL: C_ctor_base:
566 ; CHECK: mov [[SAVETHIS:r[0-9]+]], r0
567 ; CHECK: bl A_ctor_base
568 ; CHECK: mov r0, [[SAVETHIS]]
569 %0 = bitcast %struct.C* %this to %struct.A*
570 %call = tail call %struct.A* @A_ctor_base(%struct.A* %0)
571 %1 = bitcast %struct.C* %this to %struct.B*
572 %call2 = tail call %struct.B* @B_ctor_base(%struct.B* %1, i32 %x)
573 ret %struct.C* %this
574 }
575 define %struct.D* @D_ctor_base(%struct.D* %this, i32 %x) {
577 entry:
578 ; CHECK-LABEL: D_ctor_base:
579 The use of CHECK-LABEL: directives in this case ensures that the three
581 CHECK: directives only accept lines corresponding to the body of the
582 @C_ctor_base function, even if the patterns match lines found later in
583 the file. Furthermore, if one of these three CHECK: directives fail,
584 FileCheck will recover by continuing to the next block, allowing multi‐
585 ple test failures to be detected in a single invocation.
586 There is no requirement that CHECK-LABEL: directives contain strings
588 that correspond to actual syntactic labels in a source or output lan‐
589 guage: they must simply uniquely match a single line in the file being
590 verified.
591 CHECK-LABEL: directives cannot contain variable definitions or uses.
593 Directive modifiers
595 A directive modifier can be append to a directive by following the di‐
596 rective with {<modifier>} where the only supported value for <modifier>
597 is LITERAL.
598 The LITERAL directive modifier can be used to perform a literal match.
600 The modifier results in the directive not recognizing any syntax to
601 perform regex matching, variable capture or any substitutions. This is
602 useful when the text to match would require excessive escaping other‐
603 wise. For example, the following will perform literal matches rather
604 than considering these as regular expressions:
605 Input: [[[10, 20]], [[30, 40]]]
607 Output %r10: [[10, 20]]
608 Output %r10: [[30, 40]]
609 ; CHECK{LITERAL}: [[[10, 20]], [[30, 40]]]
611 ; CHECK-DAG{LITERAL}: [[30, 40]]
612 ; CHECK-DAG{LITERAL}: [[10, 20]]
613 FileCheck Regex Matching Syntax
615 All FileCheck directives take a pattern to match. For most uses of
616 FileCheck, fixed string matching is perfectly sufficient. For some
617 things, a more flexible form of matching is desired. To support this,
618 FileCheck allows you to specify regular expressions in matching
619 strings, surrounded by double braces: {{yourregex}}. FileCheck imple‐
620 ments a POSIX regular expression matcher; it supports Extended POSIX
621 regular expressions (ERE). Because we want to use fixed string matching
622 for a majority of what we do, FileCheck has been designed to support
623 mixing and matching fixed string matching with regular expressions.
624 This allows you to write things like this:
625 ; CHECK: movhpd {{[0-9]+}}(%esp), {{%xmm[0-7]}}
627 In this case, any offset from the ESP register will be allowed, and any
629 xmm register will be allowed.
630 Because regular expressions are enclosed with double braces, they are
632 visually distinct, and you don't need to use escape characters within
633 the double braces like you would in C. In the rare case that you want
634 to match double braces explicitly from the input, you can use something
635 ugly like {{[}][}]}} as your pattern. Or if you are using the repeti‐
636 tion count syntax, for example [[:xdigit:]]{8} to match exactly 8 hex
637 digits, you would need to add parentheses like this
638 {{([[:xdigit:]]{8})}} to avoid confusion with FileCheck's closing dou‐
639 ble-brace.
640 FileCheck String Substitution Blocks
642 It is often useful to match a pattern and then verify that it occurs
643 again later in the file. For codegen tests, this can be useful to al‐
644 low any register, but verify that that register is used consistently
645 later. To do this, FileCheck supports string substitution blocks that
646 allow string variables to be defined and substituted into patterns.
647 Here is a simple example:
648 ; CHECK: test5:
650 ; CHECK: notw [[REGISTER:%[a-z]+]]
651 ; CHECK: andw {{.*}}[[REGISTER]]
652 The first check line matches a regex %[a-z]+ and captures it into the
654 string variable REGISTER. The second line verifies that whatever is in
655 REGISTER occurs later in the file after an "andw". FileCheck string
656 substitution blocks are always contained in [[ ]] pairs, and string
657 variable names can be formed with the regex [a-zA-Z_][a-zA-Z0-9_]*. If
658 a colon follows the name, then it is a definition of the variable; oth‐
659 erwise, it is a substitution.
660 FileCheck variables can be defined multiple times, and substitutions
662 always get the latest value. Variables can also be substituted later
663 on the same line they were defined on. For example:
664 ; CHECK: op [[REG:r[0-9]+]], [[REG]]
666 Can be useful if you want the operands of op to be the same register,
668 and don't care exactly which register it is.
669 If --enable-var-scope is in effect, variables with names that start
671 with $ are considered to be global. All others variables are local.
672 All local variables get undefined at the beginning of each CHECK-LABEL
673 block. Global variables are not affected by CHECK-LABEL. This makes it
674 easier to ensure that individual tests are not affected by variables
675 set in preceding tests.
676 FileCheck Numeric Substitution Blocks
678 FileCheck also supports numeric substitution blocks that allow defining
679 numeric variables and checking for numeric values that satisfy a nu‐
680 meric expression constraint based on those variables via a numeric sub‐
681 stitution. This allows CHECK: directives to verify a numeric relation
682 between two numbers, such as the need for consecutive registers to be
683 used.
684 The syntax to capture a numeric value is [[#%<fmtspec>,<NUMVAR>:]]
686 where:
687 • %<fmtspec>, is an optional format specifier to indicate what number
689 format to match and the minimum number of digits to expect.
690 • <NUMVAR>: is an optional definition of variable <NUMVAR> from the
692 captured value.
693 The syntax of <fmtspec> is: #.<precision><conversion specifier> where:
695 • # is an optional flag available for hex values (see <conversion spec‐
697 ifier> below) which requires the value matched to be prefixed by 0x.
698 • .<precision> is an optional printf-style precision specifier in which
700 <precision> indicates the minimum number of digits that the value
701 matched must have, expecting leading zeros if needed.
702 • <conversion specifier> is an optional scanf-style conversion speci‐
704 fier to indicate what number format to match (e.g. hex number). Cur‐
705 rently accepted format specifiers are %u, %d, %x and %X. If absent,
706 the format specifier defaults to %u.
707 For example:
709 ; CHECK: mov r[[#REG:]], 0x[[#%.8X,ADDR:]]
711 would match mov r5, 0x0000FEFE and set REG to the value 5 and ADDR to
713 the value 0xFEFE. Note that due to the precision it would fail to match
714 mov r5, 0xFEFE.
715 As a result of the numeric variable definition being optional, it is
717 possible to only check that a numeric value is present in a given for‐
718 mat. This can be useful when the value itself is not useful, for in‐
719 stance:
720 ; CHECK-NOT: mov r0, r[[#]]
722 to check that a value is synthesized rather than moved around.
724 The syntax of a numeric substitution is [[#%<fmtspec>, <constraint>
726 <expr>]] where:
727 • <fmtspec> is the same format specifier as for defining a variable but
729 in this context indicating how a numeric expression value should be
730 matched against. If absent, both components of the format specifier
731 are inferred from the matching format of the numeric variable(s) used
732 by the expression constraint if any, and defaults to %u if no numeric
733 variable is used, denoting that the value should be unsigned with no
734 leading zeros. In case of conflict between format specifiers of sev‐
735 eral numeric variables, the conversion specifier becomes mandatory
736 but the precision specifier remains optional.
737 • <constraint> is the constraint describing how the value to match must
739 relate to the value of the numeric expression. The only currently ac‐
740 cepted constraint is == for an exact match and is the default if
741 <constraint> is not provided. No matching constraint must be speci‐
742 fied when the <expr> is empty.
743 • <expr> is an expression. An expression is in turn recursively defined
745 as:
746 • a numeric operand, or
748 • an expression followed by an operator and a numeric operand.
750 A numeric operand is a previously defined numeric variable, an inte‐
752 ger literal, or a function. Spaces are accepted before, after and be‐
753 tween any of these elements. Numeric operands have 64-bit precision.
754 Overflow and underflow are rejected. There is no support for operator
755 precedence, but parentheses can be used to change the evaluation or‐
756 der.
757 The supported operators are:
759 • + - Returns the sum of its two operands.
761 • - - Returns the difference of its two operands.
763 The syntax of a function call is <name>(<arguments>) where:
765 • name is a predefined string literal. Accepted values are:
767 • add - Returns the sum of its two operands.
769 • div - Returns the quotient of its two operands.
771 • max - Returns the largest of its two operands.
773 • min - Returns the smallest of its two operands.
775 • mul - Returns the product of its two operands.
777 • sub - Returns the difference of its two operands.
779 • <arguments> is a comma separated list of expressions.
781 For example:
783 ; CHECK: load r[[#REG:]], [r0]
785 ; CHECK: load r[[#REG+1]], [r1]
786 ; CHECK: Loading from 0x[[#%x,ADDR:]]
787 ; CHECK-SAME: to 0x[[#ADDR + 7]]
788 The above example would match the text:
790 load r5, [r0]
792 load r6, [r1]
793 Loading from 0xa0463440 to 0xa0463447
794 but would not match the text:
796 load r5, [r0]
798 load r7, [r1]
799 Loading from 0xa0463440 to 0xa0463443
800 Due to 7 being unequal to 5 + 1 and a0463443 being unequal to a0463440
802 + 7.
803 A numeric variable can also be defined to the result of a numeric ex‐
805 pression, in which case the numeric expression constraint is checked
806 and if verified the variable is assigned to the value. The unified syn‐
807 tax for both checking a numeric expression and capturing its value into
808 a numeric variable is thus [[#%<fmtspec>,<NUMVAR>: <constraint>
809 <expr>]] with each element as described previously. One can use this
810 syntax to make a testcase more self-describing by using variables in‐
811 stead of values:
812 ; CHECK: mov r[[#REG_OFFSET:]], 0x[[#%X,FIELD_OFFSET:12]]
814 ; CHECK-NEXT: load r[[#]], [r[[#REG_BASE:]], r[[#REG_OFFSET]]]
815 which would match:
817 mov r4, 0xC
819 load r6, [r5, r4]
820 The --enable-var-scope option has the same effect on numeric variables
822 as on string variables.
823 Important note: In its current implementation, an expression cannot use
825 a numeric variable defined earlier in the same CHECK directive.
826 FileCheck Pseudo Numeric Variables
828 Sometimes there's a need to verify output that contains line numbers of
829 the match file, e.g. when testing compiler diagnostics. This intro‐
830 duces a certain fragility of the match file structure, as "CHECK:"
831 lines contain absolute line numbers in the same file, which have to be
832 updated whenever line numbers change due to text addition or deletion.
833 To support this case, FileCheck expressions understand the @LINE pseudo
835 numeric variable which evaluates to the line number of the CHECK pat‐
836 tern where it is found.
837 This way match patterns can be put near the relevant test lines and in‐
839 clude relative line number references, for example:
840 // CHECK: test.cpp:[[# @LINE + 4]]:6: error: expected ';' after top level declarator
842 // CHECK-NEXT: {{^int a}}
843 // CHECK-NEXT: {{^ \^}}
844 // CHECK-NEXT: {{^ ;}}
845 int a
846 To support legacy uses of @LINE as a special string variable, FileCheck
848 also accepts the following uses of @LINE with string substitution block
849 syntax: [[@LINE]], [[@LINE+<offset>]] and [[@LINE-<offset>]] without
850 any spaces inside the brackets and where offset is an integer.
851 Matching Newline Characters
853 To match newline characters in regular expressions the character class
854 [[:space:]] can be used. For example, the following pattern:
855 // CHECK: DW_AT_location [DW_FORM_sec_offset] ([[DLOC:0x[0-9a-f]+]]){{[[:space:]].*}}"intd"
857 matches output of the form (from llvm-dwarfdump):
859 DW_AT_location [DW_FORM_sec_offset] (0x00000233)
861 DW_AT_name [DW_FORM_strp] ( .debug_str[0x000000c9] = "intd")
862 letting us set the FileCheck variable DLOC to the desired value
864 0x00000233, extracted from the line immediately preceding "intd".
865
867 Maintained by the LLVM Team (https://llvm.org/).
868
870 2003-2023, LLVM Project
87116 2023-08-24 FILECHECK(1)