This reinstates r360578 (git e47362c1ec),
reverted in r360653 (git 004393681c),
with a fix for the list added in FileCheck.rst to build without error.
Copyright:
- Linaro (changes up to diff 183612 of revision D55940)
- GraphCore (changes in later versions of revision D55940 and
in new revision created off D55940)
Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar,
arichardson, rnk
Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar,
arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60385
llvm-svn: 360665
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch introduces regular numeric
variables which can be set on the command-line.
This commit introduces regular numeric variable that can be set on the
command-line with the -D option to a numeric value. They can then be
used in CHECK patterns in numeric expression with the same shape as
@LINE numeric expression, ie. VAR, VAR+offset or VAR-offset where offset
is an integer literal.
The commit also enable strict whitespace in the verbose.txt testcase to
check that the position or the location diagnostics. It fixes one of the
existing CHECK in the process which was not accurately testing a
location diagnostic (ie. the diagnostic was correct, not the CHECK).
Copyright:
- Linaro (changes up to diff 183612 of revision D55940)
- GraphCore (changes in later versions of revision D55940 and
in new revision created off D55940)
Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk
Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60385
llvm-svn: 360578
This patch fixes PR41523
https://bugs.llvm.org/show_bug.cgi?id=41523
Regions can now nest/overlap provided that they have different names.
Anonymous regions cannot overlap.
Region end markers must specify the region name. The only exception is for when
there is only one user-defined region; in that particular case, the region end
marker doesn't need to specify a name.
Incorrect region end markers are no longer ignored. Instead, the tool reports an
error and we exit with an error code.
Added test cases to verify the new diagnostic error messages.
Updated the llvm-mca docs to reflect this feature change.
Differential Revision: https://reviews.llvm.org/D61676
llvm-svn: 360351
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch introduces the @LINE numeric
expressions.
This commit introduces a new syntax to express a relation a numeric
value in the input text must have with the line number of a given CHECK
pattern: [[#<@LINE numeric expression>]]. Further commits build on that
to express relations between several numeric values in the input text.
To help with naming, regular variables are renamed into pattern
variables and old @LINE expression syntax is referred to as legacy
numeric expression.
Compared to existing @LINE expressions, this new syntax allow arbitrary
spacing between the component of the expression. It offers otherwise the
same functionality but the commit serves to introduce some of the data
structure needed to support more general numeric expressions.
Copyright:
- Linaro (changes up to diff 183612 of revision D55940)
- GraphCore (changes in later versions of revision D55940 and
in new revision created off D55940)
Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk
Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60384
llvm-svn: 359741
Add overlap functionality to llvm-profdata tool to compute the similarity
between two profile files.
Differential Revision: https://reviews.llvm.org/D60977
llvm-svn: 359612
This adds an alias for llvm-symbolizer with different defaults so that
it can be used as a drop-in replacement for GNU's addr2line.
If a substring "addr2line" is found in the tool's name:
* it defaults "-i", "-f" and "-C" to OFF;
* it uses "--output-style=GNU" by default.
Differential Revision: https://reviews.llvm.org/D60067
llvm-svn: 358749
With the latest changes, the option gets useful for users of
llvm-symbolizer, not only for the upcoming llvm-addr2line.
Differential Revision: https://reviews.llvm.org/D60816
llvm-svn: 358748
It makes more sense to print out the number of micro opcodes that are issued
every cycle rather than the number of instructions issued per cycle.
This behavior is also consistent with the dispatch-stats: numbers from the two
views can now be easily compared.
llvm-svn: 357919
Summary:
This is an alternative to D59539.
Let's suppose we have measured 4 different opcodes, and got: `0.5`, `1.0`, `1.5`, `2.0`.
Let's suppose we are using `-analysis-clustering-epsilon=0.5`.
By default now we will start processing the `0.5` point, find that `1.0` is it's neighbor, add them to a new cluster.
Then we will notice that `1.5` is a neighbor of `1.0` and add it to that same cluster.
Then we will notice that `2.0` is a neighbor of `1.5` and add it to that same cluster.
So all these points ended up in the same cluster.
This may or may not be a correct implementation of dbscan clustering algorithm.
But this is rather horribly broken for the reasons of comparing the clusters with the LLVM sched data.
Let's suppose all those opcodes are currently in the same sched cluster.
If i specify `-analysis-inconsistency-epsilon=0.5`, then no matter
the LLVM values this cluster will **never** match the LLVM values,
and thus this cluster will **always** be displayed as inconsistent.
The solution is obviously to split off some of these opcodes into different sched cluster.
But how do i do that? Out of 4 opcodes displayed in the inconsistency report,
which ones are the "bad ones"? Which ones are the most different from the checked-in data?
I'd need to go in to the `.yaml` and look it up manually.
The trivial solution is to, when creating clusters, don't use the full dbscan algorithm,
but instead "pick some unclustered point, pick all unclustered points that are it's neighbor,
put them all into a new cluster, repeat". And just so as it happens, we can arrive
at that algorithm by not performing the "add neighbors of a neighbor to the cluster" step.
But that won't work well once we teach analyze mode to operate in on-1D mode
(i.e. on more than a single measurement type at a time), because the clustering would
depend on the order of the measurements.
Instead, let's just create a single cluster per opcode, and put all the points of that opcode into said cluster.
And simultaneously check that every point in that cluster is a neighbor of every other point in the cluster,
and if they are not, the cluster (==opcode) is unstable.
This is //yet another// step to bring me closer to being able to continue cleanup of bdver2 sched model..
Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=40880 | PR40880 ]].
Reviewers: courbet, gchatelet
Reviewed By: courbet
Subscribers: tschuett, jdoerfert, RKSimon, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59820
llvm-svn: 357152
A section containing metadata on remark diagnostics will be emitted if
the flag (-mllvm) -remarks-section is present.
For now, the metadata is:
* a magic number for remarks: "REMARKS\0"
* the version number: a little-endian uint64_t
* the absolute file path to the serialized remark diagnostics: a
null-terminated string.
Differential Revision: https://reviews.llvm.org/D59571
llvm-svn: 357043
Summary:
CoverageExporterJson::renderFiles accounts for most of the execution time given a large profdata file with multiple binaries.
Proposed solution is to generate JSON for each file in parallel and sort at the end to preserve deterministic output. Also added flags to skip generating parts of the output to trim the output size.
Patch by Sajjad Mirza (@sajjadm).
Reviewers: Dor1s, vsk
Reviewed By: Dor1s, vsk
Subscribers: liaoyuke, mgrang, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59277
llvm-svn: 356178
This patch adds a new flag named -bottleneck-analysis to print out information
about throughput bottlenecks.
MCA knows how to identify and classify dynamic dispatch stalls. However, it
doesn't know how to analyze and highlight kernel bottlenecks. The goal of this
patch is to teach MCA how to correlate increases in backend pressure to backend
stalls (and therefore, the loss of throughput).
From a Scheduler point of view, backend pressure is a function of the scheduler
buffer usage (i.e. how the number of uOps in the scheduler buffers changes over
time). Backend pressure increases (or decreases) when there is a mismatch
between the number of opcodes dispatched, and the number of opcodes issued in
the same cycle. Since buffer resources are limited, continuous increases in
backend pressure would eventually leads to dispatch stalls. So, there is a
strong correlation between dispatch stalls, and how backpressure changed over
time.
This patch teaches how to identify situations where backend pressure increases
due to:
- unavailable pipeline resources.
- data dependencies.
Data dependencies may delay execution of instructions and therefore increase the
time that uOps have to spend in the scheduler buffers. That often translates to
an increase in backend pressure which may eventually lead to a bottleneck.
Contention on pipeline resources may also delay execution of instructions, and
lead to a temporary increase in backend pressure.
Internally, the Scheduler classifies instructions based on whether register /
memory operands are available or not.
An instruction is marked as "ready to execute" only if data dependencies are
fully resolved.
Every cycle, the Scheduler attempts to execute all instructions that are ready
to execute. If an instruction cannot execute because of unavailable pipeline
resources, then the Scheduler internally updates a BusyResourceUnits mask with
the ID of each unavailable resource.
ExecuteStage is responsible for tracking changes in backend pressure. If backend
pressure increases during a cycle because of contention on pipeline resources,
then ExecuteStage sends a "backend pressure" event to the listeners.
That event would contain information about instructions delayed by resource
pressure, as well as the BusyResourceUnits mask.
Note that ExecuteStage also knows how to identify situations where backpressure
increased because of delays introduced by data dependencies.
The SummaryView observes "backend pressure" events and prints out a "bottleneck
report".
Example of bottleneck report:
```
Cycles with backend pressure increase [ 99.89% ]
Throughput Bottlenecks:
Resource Pressure [ 0.00% ]
Data Dependencies: [ 99.89% ]
- Register Dependencies [ 0.00% ]
- Memory Dependencies [ 99.89% ]
```
A bottleneck report is printed out only if increases in backend pressure
eventually caused backend stalls.
About the time complexity:
Time complexity is linear in the number of instructions in the
Scheduler::PendingSet.
The average slowdown tends to be in the range of ~5-6%.
For memory intensive kernels, the slowdown can be significant if flag
-noalias=false is specified. In the worst case scenario I have observed a
slowdown of ~30% when flag -noalias=false was specified.
We can definitely recover part of that slowdown if we optimize class LSUnit (by
doing extra bookkeeping to speedup queries). For now, this new analysis is
disabled by default, and it can be enabled via flag -bottleneck-analysis. Users
of MCA as a library can enable the generation of pressure events through the
constructor of ExecuteStage.
This patch partially addresses https://bugs.llvm.org/show_bug.cgi?id=37494
Differential Revision: https://reviews.llvm.org/D58728
llvm-svn: 355308
Part 2 of CSPGO changes (mostly related to ProfileSummary).
Note that I use a default parameter in setProfileSummary() and getSummary().
This is to break the dependency in clang. I will make the parameter explicit
after changing clang in a separated patch.
Differential Revision: https://reviews.llvm.org/D54175
llvm-svn: 355131
The patch adds support for --hash-filenames to llvm-cov. This option adds md5
hash of the source path to the name of the generated .gcov file. The option is
crucial for cases where you have multiple files with the same name but can't
use --preserve-paths as resulting filenames exceed the limit.
from gcov(1):
```
-x
--hash-filenames
By default, gcov uses the full pathname of the source files to to
create an output filename. This can lead to long filenames that
can overflow filesystem limits. This option creates names of the
form source-file##md5.gcov, where the source-file component is
the final filename part and the md5 component is calculated from
the full mangled name that would have been used otherwise.
```
Patch by Igor Ignatev!
Differential Revision: https://reviews.llvm.org/D58370
llvm-svn: 354379
Summary:
Up until the point i have looked in the source, i didn't even understood that
i can disable 'cluster' output. I have always silenced it via ` &> /dev/null`.
(And hoped it wasn't contributing much of the run time.)
While i expect that it has it's use-cases i never once needed it so far.
If i forget to silence it, console is completely flooded with that output.
How about not expecting users to opt-out of analyses,
but to explicitly specify the analyses that should be performed?
Reviewers: courbet, gchatelet
Reviewed By: courbet
Subscribers: tschuett, RKSimon, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57648
llvm-svn: 353021
If a stack trace or similar has a list of addresses from an executable
or DSO loaded at a variable address (e.g. due to ASLR), the addresses
will not directly correspond to the addresses stored in the object file.
If a user wishes to use llvm-symbolizer, they have to subtract the load
address from every address. This is somewhat inconvenient, especially as
the output of --print-address will result in the adjusted address being
listed, rather than the address coming from the stack trace, making it
harder to map results between the two.
This change adds a new switch to llvm-symbolizer --adjust-vma which
takes an offset, which is then used to automatically do this
calculation. The printed address remains the input address (allowing for
easy mapping), whilst the specified offset is applied to the addresses
when performing the lookup.
The switch is conceptually similar to llvm-objdump's new switch of the
same name (see D57051), which in turn mirrors a GNU switch. There is no
equivalent switch in addr2line.
Reviewed by: grimar
Differential Revision: https://reviews.llvm.org/D57151
llvm-svn: 352195
This change adds two options, -i and -inlines as aliases for the -inlining option to llvm-symbolizer to improve compatibility with the GNU addr2line utility which accepts these options.
It also modifies existing tests that use -inlining to exercise these new aliases as well.
This fixes PR40073.
Reviewed by: jhenderson, Quolyk, ruiu
Differential Revision: https://reviews.llvm.org/D57083
llvm-svn: 351999
This fixes https://bugs.llvm.org/show_bug.cgi?id=40072.
GNU addr2line's --functions switch is off by default, has a short alias
of -f, and does not take an argument. This patch changes llvm-symbolizer
to allow the second and third point (changing the default behaviour may
have negative impacts on users). If the option is missing a value, it
now treats it as "linkage".
This change does cause one previously valid command-line to behave
differently. Before --functions <value> was accepted, but now only
--functions=<value> is allowed (as well as --functions). The old
behaviour will result in the value being treated as a positional
argument.
The previous testing for --functions=short has been pulled out into a
new test that also tests the other accepted values and option formats.
Reviewed by: ruiu
Differential Revision: https://reviews.llvm.org/D57049
llvm-svn: 351968
The old diagnostic form of the trace produced by -v and -vv looks
like:
```
check1:1:8: remark: CHECK: expected string found in input
CHECK: abc
^
<stdin>:1:3: note: found here
; abc def
^~~
```
When dumping annotated input is requested (via -dump-input), I find
that this old trace is not useful and is sometimes harmful:
1. The old trace is mostly redundant because the same basic
information also appears in the input dump's annotations.
2. The old trace buries any error diagnostic between it and the input
dump, but I find it useful to see any error diagnostic up front.
3. FILECHECK_OPTS=-dump-input=fail requests annotated input dumps only
for failed FileCheck calls. However, I have to also add -v or -vv
to get a full set of annotations, and that can produce massive
output from all FileCheck calls in all tests. That's a real
problem when I run this in the IDE I use, which grinds to a halt as
it tries to capture all that output.
When -dump-input=fail|always, this patch suppresses the old trace from
-v or -vv. Error diagnostics still print as usual. If you want the
old trace, perhaps to see variable expansions, you can set
-dump-input=none (the default).
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D55825
llvm-svn: 351881
This change adds demangling support to the ELF side of llvm-readobj,
under the switch --demangle/-C.
The following places are demangled: symbol table dumps (static and
dynamic), relocation dumps (static and dynamic), addrsig dumps, call
graph profile dumps, and group section signature symbols.
Although GNU readelf doesn't support demangling, it is still a useful
feature to have, and brings it on a par with llvm-objdump's
capabilities.
This fixes https://bugs.llvm.org/show_bug.cgi?id=40054.
Reviewed by: grimar, rupprecht
Differential Revision: https://reviews.llvm.org/D56791
llvm-svn: 351450
Summary:
When running llvm-objdump with the -macho option objdump will by default
disassemble only the __TEXT,__text section (or __TEXT_EXEC,__text when
disassembling MH_KEXT_BUNDLE files). The -disassemble-all option is
treated no diferently than -disassemble.
This change upates llvm-objdump's MachO parsing code to disassemble all
__text sections found in a file when -disassemble-all is specified. This
is useful for disassembling files with more than one __text section, or
when disassembling files whose __text section is not present in __TEXT.
I added a lit test case that verifies "llvm-objdump -m -d" and
"llvm-objdump -m -D" produce the expected results on a reference binary.
I also updated the CommandGuide documentation for llvm-objdump.rst and
verified it renders correctly as man and html.
rdar://42899338
Reviewers: ab, pete, lhames
Reviewed By: lhames
Subscribers: rupprecht, llvm-commits
Differential Revision: https://reviews.llvm.org/D56649
llvm-svn: 351238
Part of the effort to refactoring frame pointer code generation. We used
to use two function attributes "no-frame-pointer-elim" and
"no-frame-pointer-elim-non-leaf" to represent three kinds of frame
pointer usage: (all) frames use frame pointer, (non-leaf) frames use
frame pointer, (none) frame use frame pointer. This CL makes the idea
explicit by using only one enum function attribute "frame-pointer"
Option "-frame-pointer=" replaces "-disable-fp-elim" for tools such as
llc.
"no-frame-pointer-elim" and "no-frame-pointer-elim-non-leaf" are still
supported for easy migration to "frame-pointer".
tests are mostly updated with
// replace command line args ‘-disable-fp-elim=false’ with ‘-frame-pointer=none’
grep -iIrnl '\-disable-fp-elim=false' * | xargs sed -i '' -e "s/-disable-fp-elim=false/-frame-pointer=none/g"
// replace command line args ‘-disable-fp-elim’ with ‘-frame-pointer=all’
grep -iIrnl '\-disable-fp-elim' * | xargs sed -i '' -e "s/-disable-fp-elim/-frame-pointer=all/g"
Patch by Yuanfang Chen (tabloid.adroit)!
Differential Revision: https://reviews.llvm.org/D56351
llvm-svn: 351049
This patch improves llvm-profdata show command:
(1) add -value-cutoff=<N> option: Show only those functions whose max count
values are greater or equal to N.
(2) add -list-below-cutoff option: Only output names of functions whose max
count value are below the cutoff.
(3) formats value-profile counts and prints out percentage.
Differential Revision: https://reviews.llvm.org/D56342
llvm-svn: 350673
In LTO or Thin-lto mode (though linker plugin), the module
names are of temp file names which are different for
different compilations. Using SourceFileName avoids the issue.
This should not change any functionality for current PGO as
all the current callers of getPGOFuncName() is before LTO.
llvm-svn: 350579
Extend FileCheck to dump its input annotated with FileCheck's
diagnostics: errors, good matches if -v, and additional information if
-vv. The goal is to make it easier to visualize FileCheck's matching
behavior when debugging.
Each patch in this series implements input annotations for a
particular category of FileCheck diagnostics. While the first few
patches alone are somewhat useful, the annotations become much more
useful as later patches implement annotations for -v and -vv
diagnostics, which show the matching behavior leading up to the error.
This first patch implements boilerplate plus input annotations for
error diagnostics reporting that no matches were found for a
directive. These annotations mark the search ranges of the failed
directives. Instead of using the usual `^~~`, which is used by later
patches for good matches, these annotations use `X~~` so that this
category of errors is visually distinct.
For example:
```
$ FileCheck -dump-input=help
The following description was requested by -dump-input=help to
explain the input annotations printed by -dump-input=always and
-dump-input=fail:
- L: labels line number L of the input file
- T:L labels the match result for a pattern of type T from line L of
the check file
- X~~ marks search range when no match is found
- colors error
If you are not seeing color above or in input dumps, try: -color
$ FileCheck -v -dump-input=always check1 < input1 |& sed -n '/^Input file/,$p'
Input file: <stdin>
Check file: check1
-dump-input=help describes the format of the following dump.
Full input was:
<<<<<<
1: ; abc def
2: ; ghI jkl
next:3 X~~~~~~~~ error: no match found
>>>>>>
$ cat check1
CHECK: abc
CHECK-SAME: def
CHECK-NEXT: ghi
CHECK-SAME: jkl
$ cat input1
; abc def
; ghI jkl
```
Some additional details related to the boilerplate:
* Enabling: The annotated input dump is enabled by `-dump-input`,
which can also be set via the `FILECHECK_OPTS` environment variable.
Accepted values are `help`, `always`, `fail`, or `never`. As shown
above, `help` describes the format of the dump. `always` is helpful
when you want to investigate a successful FileCheck run, perhaps for
an unexpected pass. `-dump-input-on-failure` and
`FILECHECK_DUMP_INPUT_ON_FAILURE` remain as a deprecated alias for
`-dump-input=fail`.
* Diagnostics: The usual diagnostics are not suppressed in this mode
and are printed first. For brevity in the example above, I've
omitted them using a sed command. Sometimes they're perfectly
sufficient, and then they make debugging quicker than if you were
forced to hunt through a dump of long input looking for the error.
If you think they'll get in the way sometimes, keep in mind that
it's pretty easy to grep for the start of the input dump, which is
`<<<`.
* Colored Annotations: The annotated input is colored if colors are
enabled (enabling colors can be forced using -color). For example,
errors are red. However, as in the above example, colors are not
vital to reading the annotations.
I don't know how to test color in the output, so any hints here would
be appreciated.
Reviewed By: george.karpenkov, zturner, probinson
Differential Revision: https://reviews.llvm.org/D52999
llvm-svn: 349418
RetireControlUnitStatistics now reports extra information about the ROB and the
avg/maximum number of entries consumed over the entire simulation.
Example:
Retire Control Unit - number of cycles where we saw N instructions retired:
[# retired], [# cycles]
0, 109 (17.9%)
1, 102 (16.7%)
2, 399 (65.4%)
Total ROB Entries: 64
Max Used ROB Entries: 35 ( 54.7% )
Average Used ROB Entries per cy: 32 ( 50.0% )
Documentation in llvm/docs/CommandGuide/llvmn-mca.rst has been updated to
reflect this change.
llvm-svn: 347493
In some cases it is desirable to match the same pattern repeatedly
many times. Currently the only way to do it is to copy the same
check pattern as many times as needed. And that gets pretty unwieldy
when its more than count is big.
Introducing CHECK-COUNT-<num> directive which acts like a plain CHECK
directive yet matches the same pattern exactly <num> times.
Extended FileCheckType to a struct to add Count there.
Changed some parsing routines to handle non-fixed length of directive
(all currently existing directives were fixed-length).
The code is generic enough to allow future support for COUNT in more
than just PlainCheck directives.
See motivating example for this feature in reviews.llvm.org/D54223.
Reviewed By: chandlerc, dblaikie
Differential Revision: https://reviews.llvm.org/D54336
llvm-svn: 346722
Summary:
lcov tracefiles are used by various coverage reporting tools and build
systems (e.g., Bazel). It is a simple text-based format to parse and
more convenient to use than the JSON export format, which needs
additional processing to map regions/segments back to line numbers.
It's a little unfortunate that "text" format is now overloaded to refer
specifically to JSON for export, but I wanted to avoid making any
breaking changes to the UI of the llvm-cov tool at this time.
Patch by Tony Allevato (@allevato).
Reviewers: Dor1s, vsk
Reviewed By: Dor1s, vsk
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D54266
llvm-svn: 346506
This feature makes it easy to tune FileCheck diagnostic output when
running the test suite via ninja, a bot, or an IDE. For example:
```
$ FILECHECK_OPTS='-color -v -dump-input-on-failure' \
LIT_FILTER='OpenMP/for_codegen.cpp' ninja check-clang \
| less -R
```
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D53517
llvm-svn: 346272
Summary:
The pfm counters are now in the ExegesisTarget rather than the
MCSchedModel (PR39165).
This also compresses the pfm counter tables (PR37068).
Reviewers: RKSimon, gchatelet
Subscribers: mgrang, llvm-commits
Differential Revision: https://reviews.llvm.org/D52932
llvm-svn: 345243
(Relands r344930, reverted in r344935, and now hopefully fixed for
Windows.)
While this change specifically targets FileCheck, it affects any tool
using the same SourceMgr facilities.
Previously, -color was documented in FileCheck's -help output, but
-color had no effect. Now, -color obeys its documentation: it forces
colors to be used in FileCheck diagnostics even when stderr is not a
terminal.
-color is especially helpful when combined with FileCheck's -v, which
can produce a long series of diagnostics that you might wish to pipe
to a pager, such as less -R. The WithColor extensions here will also
help to clean up color usage in FileCheck's annotated dump of input,
which is proposed in D52999.
Reviewed By: JDevlieghere, zturner
Differential Revision: https://reviews.llvm.org/D53419
llvm-svn: 345202
Thomas Preud'homme