Add support for continuously syncing profile counter updates to a file.
The motivation for this is that programs do not always exit cleanly. On
iOS, for example, programs are usually killed via a signal from the OS.
Running atexit() handlers after catching a signal is unreliable, so some
method for progressively writing out profile data is necessary.
The approach taken here is to mmap() the `__llvm_prf_cnts` section onto
a raw profile. To do this, the linker must page-align the counter and
data sections, and the runtime must ensure that counters are mapped to a
page-aligned offset within a raw profile.
Continuous mode is (for the moment) incompatible with the online merging
mode. This limitation is lifted in https://reviews.llvm.org/D69586.
Continuous mode is also (for the moment) incompatible with value
profiling, as I'm not sure whether there is interest in this and the
implementation may be tricky.
As I have not been able to test extensively on non-Darwin platforms,
only Darwin support is included for the moment. However, continuous mode
may "just work" without modification on Linux and some UNIX-likes. AIUI
the default value for the GNU linker's `--section-alignment` flag is set
to the page size on many systems. This appears to be true for LLD as
well, as its `no_nmagic` option is on by default. Continuous mode will
not "just work" on Fuchsia or Windows, as it's not possible to mmap() a
section on these platforms. There is a proposal to add a layer of
indirection to the profile instrumentation to support these platforms.
rdar://54210980
Differential Revision: https://reviews.llvm.org/D68351
The check needs to validate a counter offset before performing pointer
arithmetic with the (potentially corrupt) offset.
Found by UBSan's pointer overflow check.
rdar://54843625
Differential Revision: https://reviews.llvm.org/D66979
llvm-svn: 370826
cold versus function being newly added.
This is the second half of https://reviews.llvm.org/D66374.
Profile symbol list is the collection of function symbols showing up in
the binary which generates the current profile. It is used to discriminate
function being cold versus function being newly added. Profile symbol list
is only added for profile with ExtBinary format.
During profile use compilation, when profile-sample-accurate is enabled,
a function without profile will be regarded as cold only when it is
contained in that list.
Differential Revision: https://reviews.llvm.org/D66766
llvm-svn: 370563
Summary:
StringMap is used for storing call target to frequency map for AutoFDO. However the iterating order of StringMap is non-deterministic, which leads to non-determinism in AutoFDO profile output. Now new API getSortedCallTargets and SortCallTargets are added for deterministic ordering and output.
Roundtrip test for text profile and binary profile is added.
Reviewers: wmi, davidxl, danielcdh
Subscribers: hiraditya, mgrang, llvm-commits, twoh
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66191
llvm-svn: 369440
Summary: Fix "llvm-profdata show" so it can work with compact binary format profile. The change is to mark all functions "used" so SampleProfileReaderCompactBinary::read will read in all profiles available for dumping. The function names will be MD5 hash for compact binary format.
Reviewers: wmi, davidxl, danielcdh
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65162
llvm-svn: 368731
Currently llvm-profdata does not expect the same file name for the input profile
and the output profile.
>llvm-profdata merge A.profraw B.profraw -o B.profraw
The above command runs successfully but the resulted B.profraw is not correct.
This patch fixes the issue by moving the initialization of writer after loading
the profile.
For the show command, the following will report a confusing error of
"Empty raw profile file":
>llvm-profdata show B.profraw -o B.profraw
It's harder to fix as we need to output something before loading the input profile.
I don't think that a fix for this is worth the effort. I just make the error explicit for
the show command.
Differential Revision: https://reviews.llvm.org/D64360
llvm-svn: 365386
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
Part 4 of CSPGO changes:
(1) add support in cmake for cspgo build.
(2) fix an issue in big endian.
(3) test cases.
Differential Revision: https://reviews.llvm.org/D54175
llvm-svn: 355541
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
add a tool to generate symbol remapping files.
Summary:
The new tool llvm-cxxmap builds a symbol mapping table from a file containing
a description of partial equivalences to apply to mangled names and files
containing old and new symbol tables.
Reviewers: davidxl
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D51470
llvm-svn: 342168
There is data racing to the static variable RecordIndex in index profile reader
when merging in multiple threads. Make it a member variable in
IndexedInstrProfReader to fix this.
Differential Revision: https://reviews.llvm.org/D38431
llvm-svn: 314990
Summary: As we support multiple callsites for the same location, we need to traverse all locations to get the number of callsites.
Reviewers: davidxl
Reviewed By: davidxl
Subscribers: sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D36246
llvm-svn: 309907
Profile runtime can generate an empty raw profile (when there is no function in
the shared library). This empty profile is treated as a text format profile. A
test format profile without the flag of "#IR" is thought to be a clang
generated profile. So in llvm profile merging, we will get a bogus warning of
"Merge IR generated profile with Clang generated profile."
The fix here is to skip the empty profile (when the buffer size is 0) for
profile merge.
Reviewers: vsk, davidxl
Differential Revision: http://reviews.llvm.org/D25687
llvm-svn: 284659
Function names in ObjC can have spaces in them. This interacts poorly
with name compression, which uses spaces to separate PGO names. Fix the
issue by using a different separator and update a test.
I chose "\01" as the separator because 1) it's non-printable, 2) we
strip it from PGO names, and 3) it's the next natural choice once "\00"
is discarded (that one's overloaded).
What's changed since the original commit?
- I fixed up the covmap-V2 binary format tests using a linux VM.
- I weakened the CHECK lines in instrprof-comdat.h to account for the
fact that there have been bugfixes to clang coverage. These will be
fixed up in a follow-up.
- I added an assert to make sure we don't get bitten by this again.
- I constructed the c-general.profraw file without name compression
enabled to appease some bots.
Differential Revision: http://reviews.llvm.org/D18516
llvm-svn: 264658
Function names in ObjC can have spaces in them. This interacts poorly
with name compression, which uses spaces to separate PGO names. Fix the
issue by using a different separator and update a test.
I chose "\01" as the separator because 1) it's non-printable, 2) we
strip it from PGO names, and 3) it's the next natural choice once "\00"
is discarded (that one's overloaded).
This reverts the revert commit beaf3d18. What's changed?
- I fixed up the covmap-V2 binary format tests using a linux VM.
- I updated the expected counts in instrprof-comdat.h to account for
the fact that there have been bugfixes to clang coverage.
- I added an assert to make sure we don't get bitten by this again.
Differential Revision: http://reviews.llvm.org/D18516
llvm-svn: 264641
This reduces sizes of instrumented object files, final binaries,
process images, and raw profile data.
The format of the indexed profile data remain the same.
Differential Revision: http://reviews.llvm.org/D16388
llvm-svn: 260117
Summary: Surface counter overflow when merging profile data. Merging still occurs on overflow but counts saturate to the maximum representable value. Overflow is reported to the user.
Reviewers: davidxl, dnovillo, silvas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15547
llvm-svn: 255825
Summary:
This change adds support for specifying a weight when merging profile data with the llvm-profdata tool.
Weights are specified by using the --weighted-input=<weight>,<filename> option. Input files not specified
with this option (normal positional list after options) are given a default weight of 1.
Adding support for arbitrary weighting of input profile data allows for relative importance to be placed on the
input data from multiple training runs.
Both sampled and instrumented profiles are supported.
Reviewers: davidxl, dnovillo, bogner, silvas
Subscribers: silvas, davidxl, llvm-commits
Differential Revision: http://reviews.llvm.org/D15306
llvm-svn: 255659
This patch adds the missing functionality in parsable
text format support for value profiling.
Differential Revision: http://reviews.llvm.org/D15212
llvm-svn: 255523
Before the patch, -fprofile-instr-generate compile will fail
if no integrated-as is specified when the file contains
any static functions (the -S output is also invalid).
This patch fixed the issue. With the change, the index format
version will be bumped up by 1. Backward compatibility is
preserved with this change.
Differential Revision: http://reviews.llvm.org/D15243
llvm-svn: 255365
This change adds support for an optional weight when merging profile data with the llvm-profdata tool.
Weights are specified by adding an option ':<weight>' suffix to the input file names.
Adding support for arbitrary weighting of input profile data allows for relative importance to be placed on the
input data from multiple training runs.
Both sampled and instrumented profiles are supported.
Reviewers: dnovillo, bogner, davidxl
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14547
llvm-svn: 254669
The new option is similar to the SampleProfile dump option.
- dump raw/indexed format into text profile format
- merge the profile and output into text profile format.
Note that Value Profiling data text format is not yet designed.
That functionality will be added later.
Differential Revision: http://reviews.llvm.org/D14894
llvm-svn: 253913
This change introduces an instrumentation intrinsic instruction for
value profiling purposes, the lowering of the instrumentation intrinsic
and raw reader updates. The raw profile data files for llvm-profdata
testing are updated.
llvm-svn: 253484
With this patch we can now read and write inline stacks in sample
profiles to the binary encoded profiles.
In a subsequent patch, I will add a string table to the binary encoding.
Right now function names are emitted as strings every time we find them.
This is too bloated and will produce large files in applications with
lots of inlining.
llvm-svn: 249861
This fixes memory allocation problems by making the merge operation keep
the profile readers around until the merged profile has been emitted.
This is needed to prevent the inlined function names to disappear from
the function profiles. Since all the names are kept as references, once
the reader disappears, the names are also deallocated.
Additionally, XFAIL on big-endian architectures. The test case uses a
gcov file generated on a little-endian system.
llvm-svn: 249724
This patch adds support for reading sample profiles with inline stacks.
Inline stacks in a profile are generated when the sampled binary has
samples in inlined functions.
For instance, if main() calls foo() and foo() calls bar(), and bar() is
inlined into foo() and foo() inlined into main(), the profile may look
something like:
main total:364084 head:0
[ ... ]
2.3: _Z3fool total:243786
1: 60149
1.2: 38568
1.4: 46511
1.7: _Z3bari total:98558
1.1: 52672
1.2: 45886
At line 2, discriminator 3, main() calls foo(). In turn, foo() calls
bar() at line 1, discriminator 7.
In the textual format, this stacking of inline calls is represented
with indentation.
With this change, LLVM can now read sample profile files generated by
the create_gcov tool from https://github.com/google/autofdo.
llvm-svn: 249644
Summary:
This patch extends the 'show' and 'merge' commands in llvm-profdata to handle
sample PGO formats. Using the 'merge' command it is now possible to convert
one sample PGO format to another.
The only format that is currently not working is 'gcc'. I still need to
implement support for it in lib/ProfileData.
The changes in the sample profile support classes are needed for the
merge operation.
Reviewers: bogner
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6065
llvm-svn: 221032
This updates the instrumentation based profiling format so that when
we have multiple functions with the same name (but different function
hashes) we keep all of them instead of rejecting the later ones.
There are a number of scenarios where this can come up where it's more
useful to keep multiple function profiles:
* Name collisions in unrelated libraries that are profiled together.
* Multiple "main" functions from multiple tools built against a common
library.
* Combining profiles from different build configurations (ie, asserts
and no-asserts)
The profile format now stores the number of counters between the hash
and the counts themselves, so that multiple sets of counts can be
stored. Since this is backwards incompatible, I've bumped the format
version and added some trivial logic to skip this when reading the old
format.
llvm-svn: 214585
In some places we've been using different suffixes for the different
file formats involved in instrprof, but in others we've just
ambiguously used .profdata. Update the test files to indicate the
types of file more obviously.
No functional change.
llvm-svn: 214357
Vedant Kumar