I'm currently developing a new version of the indexed memprof format
where we deduplicate call stacks in IndexedAllocationInfo::CallStack
and IndexedMemProfRecord::CallSites. We refer to call stacks with
integer IDs, namely CallStackId, just as we refer to Frame with
FrameId. The deduplication will cut down the profile file size by 80%
in a large memprof file of mine.
As a step toward the goal, this patch teaches
IndexedMemProfRecord::{serialize,deserialize} to speak Version2. A
subsequent patch will add Version2 support to llvm-profdata.
The essense of the patch is to replace the serialization of a call
stack, a vector of FrameIDs, with that of a CallStackId. That is:
const IndexedAllocationInfo &N = ...;
...
LE.write<uint64_t>(N.CallStack.size());
for (const FrameId &Id : N.CallStack)
LE.write<FrameId>(Id);
becomes:
LE.write<CallStackId>(N.CSId);
The indexed MemProf file has a huge amount of redundancy. In a large
internal application, 82% of call stacks, stored in
IndexedAllocationInfo::CallStack, are duplicates.
We should work toward deduplicating call stacks by referring to them
with unique IDs with actual call stacks stored in a separate data
structure, much like we refer to memprof::Frame with memprof::FrameId.
At the same time, we need to facilitate a graceful transition from the
current version of the MemProf format to the next. We should be able
to read (but not write) the current version of the MemProf file even
after we move onto the next one.
With those goals in mind, I propose to have an integer ID next to
CallStack in IndexedAllocationInfo to refer to a call stack in a
succinct manner. We'll gradually increase the areas of the compiler
where IDs and call stacks have one-to-one correspondence and
eventually remove the existing CallStack field.
This patch adds call stack ID, named CSId, to IndexedAllocationInfo
and teaches the raw profile reader to compute unique call stack IDs
and store them in the new field. It does not introduce any user of
the call stack IDs yet, except in verifyFunctionProfileData.
GNU addr2line supports lookup by symbol name in addition to the existing
address lookup. llvm-symbolizer starting from
e144ae54dcb96838a6176fd9eef21028935ccd4f supports lookup by symbol name.
This change extends this lookup with possibility to specify optional
offset.
Now the address for which source information is searched for can be
specified with offset:
llvm-symbolize --obj=abc.so "SYMBOL func_22+0x12"
It decreases the gap in features of llvm-symbolizer and GNU addr2line.
This lookup now is supported for code only.
Migrated from: https://reviews.llvm.org/D139859
Pull request: https://github.com/llvm/llvm-project/pull/75067
Recent versions of GNU binutils starting from 2.39 support symbol+offset
lookup in addition to the usual numeric address lookup. This change adds
symbol lookup to llvm-symbolize and llvm-addr2line.
Now llvm-symbolize behaves closer to GNU addr2line, - if the value specified
as address in command line or input stream is not a number, it is treated as
a symbol name. For example:
llvm-symbolize --obj=abc.so func_22
llvm-symbolize --obj=abc.so "CODE func_22"
This lookup is now supported only for functions. Specification with
offset is not supported yet.
This is a recommit of 2b27948783e4bbc1132d3220d8517ef62607b558, reverted
in 39fec5457c0925bd39f67f63fe17391584e08258 because the test
llvm/test/Support/interrupts.test started failing on Windows. The test was
changed in 18f036d0105589c3175bb51a518c5d272dae61e2 and is also updated in
this commit.
Differential Revision: https://reviews.llvm.org/D149759
Recent versions of GNU binutils starting from 2.39 support symbol+offset
lookup in addition to the usual numeric address lookup. This change adds
symbol lookup to llvm-symbolize and llvm-addr2line.
Now llvm-symbolize behaves closer to GNU addr2line, - if the value specified
as address in command line or input stream is not a number, it is treated as
a symbol name. For example:
llvm-symbolize --obj=abc.so func_22
llvm-symbolize --obj=abc.so "CODE func_22"
This lookup is now supported only for functions. Specification with
offset is not supported yet.
Differential Revision: https://reviews.llvm.org/D149759
Add a MemProfReader base class which can be used directly where
symbolization and processing a raw profile is unnecessary.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D159141
Canonicalize the function name (strip suffixes etc) to ensure that
function name suffixes added by late stage passes do not cause
mismatches when memprof profile data is consumed.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D159132
Update the isRuntime check to only match against known memprof filenames
where interceptors are defined. This avoid issues where the path does
not include the directory based on how the runtime was compiled. Also
update the unittest.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D145521
value() has undesired exception checking semantics and calls
__throw_bad_optional_access in libc++. Moreover, the API is unavailable without
_LIBCPP_NO_EXCEPTIONS on older Mach-O platforms (see
_LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS).
This fixes check-llvm.
Extend the Frame struct to hold the symbol name if requested
when a RawMemProfReader object is constructed. This change updates the
tests and removes the need to pass --debug to obtain the mapping from
GUID to symbol names.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D126344
The current implementation of memprof information in the indexed profile
format stores the representation of each calling context fram inline.
This patch uses an interned representation where the frame contents are
stored in a separate on-disk hash table. The table is indexed via a hash
of the contents of the frame. With this patch, the compressed size of a
large memprof profile reduces by ~22%.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D123094
This reverts commit 0d362c90d335509c57c0fbd01ae1829e2b9c3765.
Reason: Causes the MSan buildbot to fail (see comments on
https://reviews.llvm.org/D121179 for more information
To ease profile annotation, each of the callsites in a function can be
annotated with profile data - "IR metadata format for MemProf" [1]. This
patch extends the on-disk serialized record format to store the debug
information for allocation callsites incl inline frames. This change is
incompatible with the existing format i.e. indexed profiles must be
regenerated, raw profiles are unaffected.
[1] https://groups.google.com/g/llvm-dev/c/aWHsdMxKAfE/m/WtEmRqyhAgAJ
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D121179
Since DI frames are enumerated with the leaf function at index 0, this
patch fixes the logic when IsInlineFrame is set. Also update the
unittests to check that only the last frame is marked as non-inline from
a set of DI Frames for a PC address.
Differential Revision: https://reviews.llvm.org/D121830
This patch filters out callstack frames which can't be symbolized or if
the frames belong to the runtime. Symbolization may not be possible if
debug information is unavailable or if the addresses are from a shared
library. For now we only support optimization of the main binary which
is statically linked to the compiler runtime.
Differential Revision: https://reviews.llvm.org/D120860
Currently, symbolization of stack frames occurs on demand when the instrprof writer
iterates over all the records in the raw memprof reader. With this
change we symbolize and cache the frames immediately after reading the
raw profiles. For a large internal binary this results in a runtime
reduction of ~50% (2m -> 48s) when merging a memprof raw profile with a
raw instr profile to generate an indexed profile. This change also makes
it simpler in the future to generate additional calling context
metadata to attach to each memprof record.
Differential Revision: https://reviews.llvm.org/D120430
This patch adds support for optional memory profile information to be
included with and indexed profile. The indexed profile header adds a new
field which points to the offset of the memory profile section (if
present) in the indexed profile. For users who do not utilize this
feature the only overhead is a 64-bit offset in the header.
The memory profile section contains (1) profile metadata describing the
information recorded for each entry (2) an on-disk hashtable containing
the profile records indexed via llvm::md5(function_name). We chose to
introduce a separate hash table instead of the existing one since the
indexing for the instrumented fdo hash table is based on a CFG hash
which itself is perturbed by memprof instrumentation.
This commit also includes the changes reviewed separately in D120093.
Differential Revision: https://reviews.llvm.org/D120103
This reverts commit 85355a560a33897453df2ef959e255ee725eebce.
This patch adds support for optional memory profile information to be
included with and indexed profile. The indexed profile header adds a new
field which points to the offset of the memory profile section (if
present) in the indexed profile. For users who do not utilize this
feature the only overhead is a 64-bit offset in the header.
The memory profile section contains (1) profile metadata describing the
information recorded for each entry (2) an on-disk hashtable containing
the profile records indexed via llvm::md5(function_name). We chose to
introduce a separate hash table instead of the existing one since the
indexing for the instrumented fdo hash table is based on a CFG hash
which itself is perturbed by memprof instrumentation.
Differential Revision: https://reviews.llvm.org/D118653
This reverts commit e6999040f5758f89a64b6232119b775b7bd1c85b.
Update test to fix signed int comparison warning, fix whitespace in
compiler-rt MIBEntryDef.inc file.
Differential Revision: https://reviews.llvm.org/D117256
This reverts commit 857ec0d01f8021ff0d9540fcbf6ff24e29868ba4.
Fixes -DLLVM_ENABLE_MODULES=On build by adding the new textual
header to the modulemap file.
Reviewed in https://reviews.llvm.org/D117722
This reverts commit 0f73fb18ca333e38cdb9ffa701a8db026c56041d.
Use llvm/Profile/MIBEntryDef.inc instead of relative path.
Generated the raw profile data with `-mllvm
-enable-name-compression=false` so that builbots where the reader is
built without zlib do not fail.
Also updated the test build instructions.
This reverts commit 43c2348c5b926df6bdbc5b70efaa35ecdefe12d5.
Buildbots are failing with an error on reading memprof testdata.
"Inputs/basic.profraw: profile uses zlib
compression but the profile reader was built without zlib support"
https://lab.llvm.org/buildbot/#/builders/16/builds/24490
This patch adds support for optional memory profile information to be
included with and indexed profile. The indexed profile header adds a new
field which points to the offset of the memory profile section (if
present) in the indexed profile. For users who do not utilize this
feature the only overhead is a 64-bit offset in the header.
The memory profile section contains (1) profile metadata describing the
information recorded for each entry (2) an on-disk hashtable containing
the profile records indexed via llvm::md5(function_name). We chose to
introduce a separate hash table instead of the existing one since the
indexing for the instrumented fdo hash table is based on a CFG hash
which itself is perturbed by memprof instrumentation.
Differential Revision: https://reviews.llvm.org/D118653
Use the macro based format to add a wrapper around the MemInfoBlock
when stored in the MemProfRecord. This wrapped block can then be
serialized/deserialized based on a schema specified by a list of enums.
Differential Revision: https://reviews.llvm.org/D117256
This patch refactors out the MemInfoBlock definition into a macro based
header which can be included to generate enums, structus and code for
each field recorded by the memprof profiling runtime.
Differential Revision: https://reviews.llvm.org/D117722
This reverts commit dbf47d227d080e4eb7239b589660f51d7b08afa9.
Reapply https://reviews.llvm.org/D116784 now that
https://reviews.llvm.org/D118413 has landed with a couple of fixes:
* fix raw profile reader unaligned access identified by ubsan
* fix windows build by using MOCK_CONST_METHOD3 instead of MOCK_METHOD.
This change extends the RawMemProfReader to read all the sections of the
raw profile and symbolize the virtual addresses recorded as part of the
callstack for each allocation. For now the symbolization is used to
display the contents of the profile with llvm-profdata.
Differential Revision: https://reviews.llvm.org/D116784