The number of samples collected at the head of a function only make
sense for top-level functions (i.e., those actually called as opposed to
being inlined inside another).
Head samples essentially count the time spent inside the function's
prologue. This clearly doesn't make sense for inlined functions, so we
were always emitting 0 in those.
llvm-svn: 250539
This adjusts all integers in the reader/writer to reflect the types
stored on profile files. They should all be unsigned 32-bit or 64-bit
values. Changed all associated internal types to be uint32_t or
uint64_t.
The only place that needed some adjustments is in the sample profile
transformation. Altough the weight read from the profile are 64-bit
values, the internal API for branch weights only accepts 32-bit values.
The pass now saturates weights that overflow uint32_t.
llvm-svn: 250427
This adds documentation for the binary profile encoding and moves the
documentation for the text encoding into the header file
SampleProfReader.h.
llvm-svn: 250309
Binary encoded profiles used to encode all function names inline at
every reference. This is clearly suboptimal in terms of space. This
patch fixes this by adding a name table to the header of the file.
llvm-svn: 250241
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
Given the work we are doing on ThinLTO, we will never need to support
module groups and working sets in GCC's implementation of LIPO. These
are currently dead code, and will continue to be so.
llvm-svn: 249351
Add support to the indexed instrprof reader and writer for the format
that will be used for value profiling.
Patch by Betul Buyukkurt, with minor modifications.
llvm-svn: 248833
This adds enough machinery to support reading simple GCC AutoFDO
profiles. It now supports reading flat profiles (no function calls).
Subsequent patches will add support for:
- Inlined calls (in particular, the inline call stack is not traversed
to accumulate samples).
- Working sets and modules. These are used mostly for GCC's LIPO
optimizations, so they're not needed in LLVM atm. I'm not sure that
we will ever need them. For now, I've if0'd around the calls.
The patch also adds support in GCOV.h for gcov version V704 (generated
by GCC's profile conversion tool).
llvm-svn: 247874
This version fixes a missing include that MSVC noticed and
clarifies the ownership of the counter buffer that's passed to
InstrProfRecord.
This restores r240206, which was reverted in r240208.
Patch by Betul Buyukkurt.
llvm-svn: 240360
The reason we need to search by name rather than by Triple::ArchType
is to handle subarchitecture correclty. There is no different ArchType
for the x86_64h architecture (it identifies itself as x86_64), or for
the various ARM subarches. The only way to get to the subarch slice
in an universal binary is to search by name.
This issue led to hard to debug and transient symbolication failures
in Asan tests (it mostly works, because the files are very similar).
This also affects the Profiling infrastucture as it is the other user
of that API.
Reviewers: samsonov, bogner
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10604
llvm-svn: 240339
Seems like MSVC doesn't like this:
InstrProf.h(49) : error C2614: 'llvm::InstrProfRecord' : illegal member initialization: 'Hash' is not a base or member
This reverts r240206.
llvm-svn: 240208
This consolidates the logic to read instrprof records into the on disk
hash table's lookup trait and makes us copy the counter data instead
of taking references to it as we read. This will simplify further
changes to the format.
Patch by Betul Buyukkurt.
llvm-svn: 240206
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
llvm/lib/
Thanks to Eugene Kosov for the original patch!
llvm-svn: 240137
`LLVM_ENABLE_MODULES` builds sometimes fail because `Intrinsics.td`
needs to regenerate `Instrinsics.h` before anyone can include anything
from the LLVM_IR module. Represent the dependency explicitly to prevent
that.
llvm-svn: 239796
As noted on Errc.h:
// * std::errc is just marked with is_error_condition_enum. This means that
// common patters like AnErrorCode == errc::no_such_file_or_directory take
// 4 virtual calls instead of two comparisons.
And on some libstdc++ those virtual functions conclude that
------------------------
int main() {
std::error_code foo = std::make_error_code(std::errc::no_such_file_or_directory);
return foo == std::errc::no_such_file_or_directory;
}
-------------------------
should exit with 0.
llvm-svn: 239683
When we generate coverage data, we explicitly set each coverage map's
alignment to 8 (See InstrProfiling::lowerCoverageData), but when we
read the coverage data, we assume consecutive maps are exactly
adjacent. When we're dealing with 32 bit, maps can end on a 4 byte
boundary, causing us to think the padding is part of the next record.
Fix this by adjusting the buffer to an appropriately aligned address
between records.
This is pretty awkward to test, as it requires a binary with multiple
coverage maps to hit, so we'd need to check in multiple source files
and a binary blob as inputs.
llvm-svn: 239129
If we have a coverage mapping but no profile data for a function,
calling it mismatched is misleading. This can just as easily be
unreachable code that was stripped from the binary. Instead, treat
these the same as functions where we have an explicit "zero" coverage
map by setting the count to zero for each mapped region.
llvm-svn: 237298
Since the coverage mapping reader and the instrprof reader were
emitting a shared set of error codes, the error messages you'd get
back from llvm-cov were ambiguous about what was actually wrong. Add
another error category to fix this.
I've also improved the wording on a couple of the instrprof errors,
for consistency.
llvm-svn: 236665
This makes the reader check the endianness of the object file its
given and behave appropriately. For the test I dug up a really old
linker and created a ppc-apple-darwin file for llvm-cov to read.
llvm-svn: 232422
This code was casting regions of a memory buffer to a couple of
different structs. This is wrong in a few ways:
1. It breaks aliasing rules.
2. If the buffer isn't aligned, it hits undefined behaviour.
3. It completely ignores endianness differences.
4. The structs being defined for this aren't specifying their padding
properly, so this doesn't even represent the data properly on some
platforms.
This commit is mostly NFC, except that it fixes reading coverage for
32 bit binaries as a side effect of getting rid of the mispadded
structs. I've included a test for that.
I've also baked in that we only handle little endian more explicitly,
since that was true in practice already. I'll fix this to handle
endianness properly in a followup commit.
llvm-svn: 232346
Creating BinaryCoverageReader is a strange and complicated dance where
the constructor sets error codes that member functions will later
read, and the object is in an invalid state if readHeader isn't
immediately called after construction.
Instead, make the constructor private and add a static create method
to do the construction properly. This also has the benefit of removing
readHeader completely and simplifying the interface of the object.
llvm-svn: 230676
This fixes an error introduced in r228934 where None was converted to
an int instead of the int being converted to an Optional as intended.
We make that sort of mistake a compile error by changing NoneType into
a scoped enum.
Finally, provide a static NoneType called None to avoid forcing all
users to spell it NoneType::None.
llvm-svn: 229980
This was leading to duplicate counts when a code region happened to
overlap exactly with an expansion. The combining behaviour only makes
sense for code regions.
llvm-svn: 229723
This comes up when we generate coverage for a function but don't end
up emitting the function at all - dead static functions or inline
functions that aren't referenced in a particular TU, for example. In
these cases we'd like to show that the function was never called,
which is trivially true.
llvm-svn: 229717
Make CoverageMapping easier to create, so that we can write targeted
unit tests for its internals, and add a some infrastructure to write
these tests. Finally, add a simple unit test for basic functionality.
llvm-svn: 229709
Have the InstrProfWriter return a MemoryBuffer instead of a
std::string. This fixes the alignment issues the reader would hit, and
it's a more appropriate type for this anyway.
I've also removed an ugly helper function that's not needed since
we're allowing initializer lists now, and updated some error code
checks based on MSVC's issues with r229473.
This reverts r229483, reapplying r229478.
llvm-svn: 229602
This added API to the InstrProfWriter to write to a string so I could
write unittests without using temp files. This doesn't really work,
since the format has tighter alignment requirements than a char.
This reverts r229478 and its follow-up, r229481.
llvm-svn: 229483
This required some minor API to be added to these types to avoid
needing temp files.
Also, I've used initializer lists in the tests, as MSVC 2013 claims to
support them. I'll redo this without them if the bots complain.
llvm-svn: 229455
