This patch fixes a couple of places where memprof-related metadata
(!memprof and !callsite) were being dropped, and one place where PGO
metadata (!prof) was being dropped.
All were due to instances of combineMetadata() being invoked. That
function drops all metadata not in the list provided by the client, and
also drops any not in its switch statement.
Memprof metadata needed a case in the combineMetadata switch statement.
For now we simply keep the metadata of the instruction being kept, which
doesn't retain all the profile information when two calls with
memprof metadata are being combined, but at least retains some.
For the memprof metadata being dropped during call CSE, add memprof and
callsite metadata to the list of known ids in combineMetadataForCSE.
Neither memprof nor regular prof metadata were in the list of known ids
for the callsite in MemCpyOptimizer, which was added to combine AA
metadata after optimization of byval arguments fed by memcpy
instructions, and similar types of optimizations of memcpy uses.
There is one other callsite of combineMetadata, but it is only invoked
on load instructions, which do not carry these types of metadata.
Emit message when we have aliased contexts that are conservatively
hinted not cold. This is not a change in behavior, just in message when
the -memprof-report-hinted-sizes flag is enabled.
Improve the information printed when -memprof-report-hinted-sizes is
enabled. Now print the full context hash computed from the original
profile, similar to what we do when reporting matching statistics. This
will make it easier to correlate with the profile.
Note that the full context hash must be computed at profile match time
and saved in the metadata and summary, because we may trim the context
during matching when it isn't needed for distinguishing hotness.
Similarly, due to the context trimming, we may have more than one full
context id and total size pair per MIB in the metadata and summary,
which now get a list of these pairs.
Remove the old aggregate size from the metadata and summary support.
One other change from the prior support is that we no longer write the
size information into the combined index for the LTO backends, which
don't use this information, which reduces unnecessary bloat in
distributed index files.
createMIBNode does not modify MIBCallStack, so we can take ArrayRef
instead.
While I am at it, this patch changes the type of MIBPayload to
SmallVector. We put at most three elements, so we can avoid a heap
allocation.
This is the first step in being able to track the total profiled sizes
of allocations successfully marked as cold.
Under a new option -memprof-report-hinted-sizes:
- For unambiguous (non-context-sensitive) allocations, print the
profiled size and the allocation coldness, along with a hash of the
allocation's location (to allow for deduplication across modules or
inline instances).
- For context sensitive allocations, add the size as a 3rd operand on
the MIB metadata. A follow on patch will propagate this through to the
thin link where the sizes will be reported for each context after
cloning.
I'm planning to remove StringRef::equals in favor of
StringRef::operator==.
- StringRef::operator==/!= outnumber StringRef::equals by a factor of
53 under llvm/ in terms of their usage.
- The elimination of StringRef::equals brings StringRef closer to
std::string_view, which has operator== but not equals.
- S == "foo" is more readable than S.equals("foo"), especially for
!Long.Expression.equals("str") vs Long.Expression != "str".
Add "Hot" AllocationType (in addition to existing cold, notcold).
Use lifetime access density as metric to identify hot allocations.
Treat hot as notcold for MemProfContextDisambiguation for now
before the disambiguation for "hot" is done.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D149932
Now that the runtime tracks the lifetime access density directly, we can
use that directly in the threshold checks instead of less accurately
computing from other statistics.
Differential Revision: https://reviews.llvm.org/D149684
As suggested in D140908, make the hasSingleAllocType helper non-static
so that it can be used in other files. Add unit testing.
Differential Revision: https://reviews.llvm.org/D144318
This restores commit 98ed423361de2f9dc0113a31be2aa04524489ca9 and
follow on fix 00c22351ba697dbddb4b5bf0ad94e4bcea4b316b, which were
reverted in 5d938eb6f79b16f55266dd23d5df831f552ea082 due to an
MSVC bot failure. I've included a fix for that failure.
Differential Revision: https://reviews.llvm.org/D135714
This reverts commit 00c22351ba697dbddb4b5bf0ad94e4bcea4b316b.
This reverts commit 98ed423361de2f9dc0113a31be2aa04524489ca9.
Seemingly MSVC has some kind of issue with this patch, in terms of linking:
https://lab.llvm.org/buildbot/#/builders/123/builds/14137
I'll post more detail on D135714 momentarily.
This restores 47459455009db4790ffc3765a2ec0f8b4934c2a4, which was
reverted in commit 452a14efc84edf808d1e2953dad2c694972b312f, along with
fixes for a couple of bot failures.
Implements the ThinLTO summary support for memprof related metadata.
This includes support for the assembly format, and for building the
summary from IR during ModuleSummaryAnalysis.
To reduce space in both the bitcode format and the in memory index,
we do 2 things:
1. We keep a single vector of all uniq stack id hashes, and record the
index into this vector in the callsite and allocation memprof
summaries.
2. When building the combined index during the LTO link, the callsite
and allocation memprof summaries are only kept on the FunctionSummary
of the prevailing copy.
Differential Revision: https://reviews.llvm.org/D135714
Adds a number of utilities that are used to help create and update
memprof related metadata. These will be used during profile matching
and annotation, as well as by the inliner when updating the metadata.
Also adds unit tests for the utilities.
See also related RFCs:
RFC: Sanitizer-based Heap Profiler [1]
RFC: A binary serialization format for MemProf [2]
RFC: IR metadata format for MemProf [3]
(Note that the IR metadata format has changed from the RFC during
implementation, as described in the preceeding patch adding the basic
metadata and verification support.)
Depends on D128141.
Differential Revision: https://reviews.llvm.org/D128854
