Summary:
This patch finishes up support for handling sampling profiles in both
text and binary formats. The new binary format uses uleb128 encoding to
represent numeric values. This makes profiles files about 25% smaller.
The profile writer class can write profiles in the existing text and the
new binary format. In subsequent patches, I will add the capability to
read (and perhaps write) profiles in the gcov format used by GCC.
Additionally, I will be adding support in llvm-profdata to manipulate
sampling profiles.
There was a bit of refactoring needed to separate some code that was in
the reader files, but is actually common to both the reader and writer.
The new test checks that reading the same profile encoded as text or
raw, produces the same results.
Reviewers: bogner, dexonsmith
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6000
llvm-svn: 220915
There are two methods in SectionRef that can fail:
* getName: The index into the string table can be invalid.
* getContents: The section might point to invalid contents.
Every other method will always succeed and returning and std::error_code just
complicates the code. For example, a section can have an invalid alignment,
but if we are able to get to the section structure at all and create a
SectionRef, we will always be able to read that invalid alignment.
llvm-svn: 219314
Every time we were adding or removing an expression when generating a
coverage mapping we were doing a linear search to try and deduplicate
the list. The indices in the list are important, so we can't just
replace it by a DenseMap entirely, but an auxilliary DenseMap for fast
lookup massively improves the performance issues I was seeing here.
llvm-svn: 218892
When I was preparing r218879 for commit, I removed an early return
that I decided was just noise. It wasn't. This is r218879 no-crash
edition.
This reverts commit r218881, reapplying r218879.
llvm-svn: 218887
The Terms vector here represented a polynomial of of all possible
counters, and is used to simplify expressions when generating coverage
mapping. There are a few problems with this:
1. Keeping the vector as a member is wasteful, since we clear it every
time we use it.
2. Most expressions refer to a subset of the counters, so we end up
iterating over a large number of zeros doing nothing a lot of the
time.
This updates the user of the vector to store the terms locally, and
uses a sort and combine approach so that we only operate on counters
that are actually used in a given expression. For small cases this
makes very little difference, but in cases with a very large number of
counted regions this is a significant performance fix.
llvm-svn: 218879
When writing a coverage mapping we iterate through the mapping regions
in order of FileID, but we were then repeatedly searching from the
beginning of the list to count the number of regions with a given
FileID.
It is simpler and more efficient to search forward from the current
iterator to find the number of regions.
llvm-svn: 218842
This commit fixes llvm-cov's function coverage metric by using the number of executed functions instead of the number of fully covered functions.
Differential Revision: http://reviews.llvm.org/D5196
llvm-svn: 218672
If we have multiple coverage counts for the same segment, we need to
add them up rather than arbitrarily choosing one. This fixes that and
adds a test with template instantiations to exercise it.
llvm-svn: 218432
This splits the logic for actually looking up coverage information
from the logic that displays it. These were tangled rather thoroughly
so this change is a bit large, but it mostly consists of moving things
around. The coverage lookup logic itself now lives in the library,
rather than being spread between the library and the tool.
llvm-svn: 218184
It isn't always useful to skip blank lines, as evidenced by the
somewhat awkward use of line_iterator in llvm-cov. This adds a knob to
control whether or not to skip blanks.
llvm-svn: 217960
The raw profiles that are generated in compiler-rt always add padding
so that each profile is aligned, so we can simply treat files that
don't have this property as malformed.
Caught by Alexey's new ubsan bot. Thanks!
llvm-svn: 217708
Summary:
This patch moves the profile reading logic out of the Sample Profile
transformation into a generic profile reader facility in
lib/ProfileData.
The intent is to use this new reader to implement a sample profile
reader/writer that can be used to convert sample profiles from external
sources into LLVM.
This first patch introduces no functional changes. It moves the profile
reading code from lib/Transforms/SampleProfile.cpp into
lib/ProfileData/SampleProfReader.cpp.
In subsequent patches I will:
- Add a bitcode format for sample profiles to allow for more efficient
encoding of the profile.
- Add a writer for both text and bitcode format profiles.
- Add a 'convert' command to llvm-profdata to be able to convert between
the two (and serve as entry point for other sample profile formats).
Reviewers: bogner, echristo
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5250
llvm-svn: 217437
This commit expands llvm-cov's functionality by adding support for a new code coverage
tool that uses LLVM's coverage mapping format and clang's instrumentation based profiling.
The gcov compatible tool can be invoked by supplying the 'gcov' command as the first argument,
or by modifying the tool's name to end with 'gcov'.
Differential Revision: http://reviews.llvm.org/D4445
llvm-svn: 216300
The profile data format was recently updated and the new indexing api
requires the code coverage tool to know the function's hash as well
as the function's name to get the execution counts for a function.
Differential Revision: http://reviews.llvm.org/D4994
llvm-svn: 216207
Owning the buffer is somewhat inflexible. Some Binaries have sub Binaries
(like Archive) and we had to create dummy buffers just to handle that. It is
also a bad fit for IRObjectFile where the Module wants to own the buffer too.
Keeping this ownership would make supporting IR inside native objects
particularly painful.
This patch focuses in lib/Object. If something elsewhere used to own an Binary,
now it also owns a MemoryBuffer.
This patch introduces a few new types.
* MemoryBufferRef. This is just a pair of StringRefs for the data and name.
This is to MemoryBuffer as StringRef is to std::string.
* OwningBinary. A combination of Binary and a MemoryBuffer. This is needed
for convenience functions that take a filename and return both the
buffer and the Binary using that buffer.
The C api now uses OwningBinary to avoid any change in semantics. I will start
a new thread to see if we want to change it and how.
llvm-svn: 216002
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
llvm-svn: 215558
This flag will be used by the coverage tool to help
compute the execution counts for each line in a source file.
Differential Revision: http://reviews.llvm.org/D4746
llvm-svn: 214740
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
This moves some tests around to make it clearer what's being tested,
and adds very rudimentary comment syntax to the text input format to
make specifying this kind of test a little bit simpler.
llvm-svn: 214235
This patch removes the empty coverage mapping regions.
Those regions were produced by clang's old mapping region generation
algorithm, but the new algorithm doesn't generate them.
llvm-svn: 213981
This patch implements the data structures, the reader and
the writers for the new code coverage mapping system.
The new code coverage mapping system uses the instrumentation
based profiling to provide code coverage analysis.
llvm-svn: 213910
This patch implements the data structures, the reader and
the writers for the new code coverage mapping system.
The new code coverage mapping system uses the instrumentation
based profiling to provide code coverage analysis.
llvm-svn: 213909
This code was never being used and any use of it would look fairly strange.
For example, it would try to map a object_error::parse_failed to
std::errc::invalid_argument.
llvm-svn: 210912
The idea of this patch is to turn llvm/Support/system_error.h into a
transitional header that just brings in the erorr_code api to the llvm
namespace. I will remove it shortly afterwards.
The cases where the general idea needed some tweaking:
* std::errc is a namespace in msvc, so we cannot use "using std::errc". I could
add an #ifdef, but there were not that many uses, so I just added std:: to
them in this patch.
* Template specialization had to be moved to the std namespace in this
patch set already.
* The msvc implementation of default_error_condition doesn't seem to
provide the same transformations as we need. Not too surprising since
the standard doesn't actually say what "equivalent" means. I fixed the
problem by keeping our old mapping and using it at error_code
construction time.
Despite these shortcomings I think this is still a good thing. Some reasons:
* The different implementations of system_error might improve over time.
* It removes 925 lines of code from llvm already.
* It removes 6313 bytes from the text segment of the clang binary when
it is built with gcc and 2816 bytes when building with clang and
libstdc++.
llvm-svn: 210687
Allow multiple raw profiles to coexist in a single .profraw file,
given the following conditions:
- Zero padding at the end of or between profiles will be skipped.
- Each profile must start with a valid header.
- Mixing endianness or pointer sizes in concatenated profiles files is
not allowed.
This is needed to handle cases where a program's shared libraries are
profiled as well as the main executable itself, as we'll need to emit
each executable's counters. Combining the tables in the runtime would
be expensive for the instrumented program.
rdar://16918688
llvm-svn: 208938
We're currently copying CounterData from InstrProfWriter into the
OnDiskHashTable, even though we don't need to, and then carelessly
leaking those copies. A const pointer is much better here.
llvm-svn: 207009
This adds support for an indexed instrumentation based profiling
format, which is just a small header and an on disk hash table. This
format will be used by clang's -fprofile-instr-use= for PGO.
llvm-svn: 206656
Since the profile can come from 32-bit machines, we need to check the
pointer size. Change the magic number to facilitate this.
Adds tests for reading 32-bit and 64-bit binaries (both big- and
little-endian). The tests write a binary using printf in RUN lines
(like raw-magic-but-no-header.test). Assuming the bots don't complain,
this seems like a better way forward for testing RawInstrProfReader than
committing binary files.
<rdar://problem/16400648>
llvm-svn: 204557
Read a raw binary profile that corresponds to a memory dump from the
runtime profile.
The test is a binary file generated from
cfe/trunk/test/Profile/c-general.c with the new compiler-rt runtime and
the matching text version of the input. It includes instructions on how
to regenerate.
<rdar://problem/15950346>
llvm-svn: 204496
This isn't a format we'll want to write out in practice, but moving it
to the writer library simplifies llvm-profdata and isolates it from
further changes to the format.
This also allows us to update the tests to not rely on the text output
format.
llvm-svn: 204489
This introduces the ProfileData library and updates llvm-profdata to
use this library for reading profiles. InstrProfReader is an abstract
base class that will be subclassed for both the raw instrprof data
from compiler-rt and the efficient instrprof format that will be used
for PGO.
llvm-svn: 204482
Diego Novillo