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
DenseMap is the wrong data structure to use for sample records and call
sites. The keys are too large, causing massive core memory growth when
reading profiles.
Before this patch, a 21Mb input profile was causing the compiler to grow
to 3Gb in memory. By switching to std::map, the compiler now grows to
300Mb in memory.
There still are some opportunities for memory footprint reduction. I'll
be looking at those next.
llvm-svn: 255389
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
It caused link errors of the form:
InstrProfiling.c:(.text.__llvm_profile_instrument_target+0x1c0): undefined reference to `__sync_fetch_and_add_8'
We had a network outage at the time of the commit so the first build to show a
problem is http://lab.llvm.org:8011/builders/clang-cmake-mips/builds/10827
llvm-svn: 253656
When dumping function samples or writing them out as text format, it
helps if the samples are emitted sorted by source location. The sorting
of the maps is a bit slow, so we only do it on demand.
llvm-svn: 253568
Summary:
This change adds MathExtras helper functions for handling unsigned, saturating addition and multiplication. It also updates the instrumentation and sample profile merge implementations to use them.
Reviewers: dnovillo, bogner, davidxl
Subscribers: davidxl, llvm-commits
Differential Revision: http://reviews.llvm.org/D14720
llvm-svn: 253497
Summary:
This change adds MathExtras helper functions for handling unsigned, saturating addition and multiplication. It also updates the instrumentation and sample profile merge implementations to use them.
No functional changes.
Reviewers: dnovillo, bogner, davidxl
Subscribers: davidxl, llvm-commits
Differential Revision: http://reviews.llvm.org/D14720
llvm-svn: 253412
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
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
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
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
utils/sort_includes.py.
I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.
llvm-svn: 225974
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
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
