Restore "[MemProf] Use new option/pass for profile feedback and matching"

This restores commit b4a82b62258c5f650a1cccf5b179933e6bae4867, reverted
in 3ab7ef28eebf9019eb3d3c4efd7ebfd160106bb1 because

Restore "[MemProf] Use new option/pass for profile feedback and matching"

This restores commit b4a82b62258c5f650a1cccf5b179933e6bae4867, reverted
in 3ab7ef28eebf9019eb3d3c4efd7ebfd160106bb1 because it was thought to
cause a bot failure, which ended up being unrelated to this patch set.

Differential Revision: https://reviews.llvm.org/D154856

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Revert "[MemProf] Use new option/pass for profile feedback and matching"

This reverts commit b4a82b62258c5f650a1cccf5b179933e6bae4867.

Broke AMDGPU OpenMP Offload buildbot

[MemProf] Use new option/pass for profile feedback and matching

Previously the MemProf profile was expected to be in the same profile
file as a normal PGO profile, passed via the usual -fprofile-use

[MemProf] Use new option/pass for profile feedback and matching

Previously the MemProf profile was expected to be in the same profile
file as a normal PGO profile, passed via the usual -fprofile-use=
option, and was matched in the same pass. To simplify profile
preparation, since the raw MemProf profile requires the binary for
symbolization and may be simpler to index separately from the raw PGO
profile, and also to enable providing a MemProf profile for a SamplePGO
build, separate out the MemProf feedback option and matching pass.

This patch adds the -fmemory-profile-use=${file} option, and the
provided file is passed down to LLVM and ultimately used in a new
MemProfUsePass which performs the matching of just the memory profile
contents of that file.

Note that a single profile file containing both normal PGO and MemProf
profile data is still supported, and the relevant profile data is
matched by the appropriate matching pass(es) based on which option(s)
the profile is provided with (the same profile file can be supplied to
both feedback options).

Differential Revision: https://reviews.llvm.org/D154856

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Restore "[MemProf] Memprof profile matching and annotation"

This reverts commit 794b7ea960ccc3222f2af582efadbc5e5c464292, and
thus restores commit a212d8da94d08e229aa8d65283e4b116310bba10, and
follo

Restore "[MemProf] Memprof profile matching and annotation"

This reverts commit 794b7ea960ccc3222f2af582efadbc5e5c464292, and
thus restores commit a212d8da94d08e229aa8d65283e4b116310bba10, and
follow on fixes 0cd6763fa93159b84d70a5bb602c24996acaafaa,
e9ff53d42feac7fc157718523275619a8106f2f3, and
37c6a25e9ab230e5e21fa34e246d9fec55275df0.

Use a hash function (BLAKE3) instead of hash_combine/hash_code which are
not guaranteed to be stable across executions.

Additionally, it adds a "REQUIRES: x86_64-linux" to the tests that have
raw profile inputs to avoid failures on big endian bots.

Reviewers: snehasish, davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D128142

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[MemProf] Memprof profile matching and annotation

Profile matching and IR annotation for memprof profiles.

See also related RFCs:
RFC: Sanitizer-based Heap Profiler [1]
RFC: A binary serialization

[MemProf] Memprof profile matching and annotation

Profile matching and IR annotation for memprof profiles.

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.

The matching is performed during the normal PGO annotation phase, to
ensure that the inlines applied in the IR at that point are a subset
of the inlines in the profiled binary and thus reflected in the
profile's call stacks. This is important because the call frames are
associated with functions in the profile based on the inlining in the
symbolized call stacks, and this simplifies locating the subset of
profile data relevant for matching onto each function's IR.

The PGOInstrumentationUse pass is enhanced to perform matching for
whatever combination of memprof and regular PGO profile data exists in
the profile.

Using the utilities introduced in D128854:
The memprof profile data for each context is converted to "cold" or
"notcold" based on parameterized thresholds for size, access count, and
lifetime. The memprof allocation contexts are trimmed to the minimal
amount of context required to uniquely identify whether the context is
cold or not cold. For allocations where all profiled contexts have the
same allocation type, no memprof metadata is attached and instead the
allocation call is directly annotated with an attribute specifying the
alloction type. This is the same attributed that will be applied to
allocation calls once cloned for different contexts, and later used
during LibCall simplification to emit allocation hints [4].

Depends on D128141 and D128854.

[1] https://lists.llvm.org/pipermail/llvm-dev/2020-June/142744.html
[2] https://lists.llvm.org/pipermail/llvm-dev/2021-September/153007.html
[3] https://discourse.llvm.org/t/rfc-ir-metadata-format-for-memprof/59165
[4] https://github.com/google/tcmalloc/commit/ab87cf382dc56784f783f3aaa43d6d0465d5f385

Differential Revision: https://reviews.llvm.org/D128142

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