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llvm-profdata: Indirect infrequently used fields to reduce memory usage

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Examining a large profile example, it seems relatively few records have
non-empty IndirectCall and MemOP data, so indirecting these through a
unique_ptr (non-null only when they are non-empty) Reduces memory usage
on this particular example from 14GB to 10GB according to valgrind's
massif.

I suspect it'd still be worth moving InstrProfWriter to its own data
structure that had Counts and the indirected IndirectCall+MemOP, and did
not include the Name, Hash, or Error fields. This would reduce the size
of this dominant data structure by half of this new, lower amount.
(Name(2), Hash(1), Error(1) ~= Counts(vector, 3), ValueProfData
(unique_ptr, 1))
-> From code review feedback, might actually refactor InstrProfRecord
itself to have a sub-struct with all the counts, and use that from
InstrProfWriter, rather than InstrProfWriter owning its own data
structure for this.

Reviewers: davidxl

Differential Revision: https://reviews.llvm.org/D34694

llvm-svn: 306631
This commit is contained in:
David Blaikie
2017-06-29 02:51:58 +00:00
parent 1631129834
commit d16a61d2c8
2 changed files with 66 additions and 30 deletions
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15
llvm/lib/ProfileData/InstrProf.cpp
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@@ -504,9 +504,11 @@ void InstrProfRecord::mergeValueProfData(uint32_t ValueKind,
SIPE.addError(instrprof_error::value_site_count_mismatch);
return;
}
if (!ThisNumValueSites)
return;
std::vector<InstrProfValueSiteRecord> &ThisSiteRecords =
getValueSitesForKind(ValueKind);
std::vector<InstrProfValueSiteRecord> &OtherSiteRecords =
getOrCreateValueSitesForKind(ValueKind);
MutableArrayRef<InstrProfValueSiteRecord> OtherSiteRecords =
Src.getValueSitesForKind(ValueKind);
for (uint32_t I = 0; I < ThisNumValueSites; I++)
ThisSiteRecords[I].merge(SIPE, OtherSiteRecords[I], Weight);
@@ -533,11 +535,8 @@ void InstrProfRecord::merge(InstrProfRecord &Other, uint64_t Weight) {
}
void InstrProfRecord::scaleValueProfData(uint32_t ValueKind, uint64_t Weight) {
uint32_t ThisNumValueSites = getNumValueSites(ValueKind);
std::vector<InstrProfValueSiteRecord> &ThisSiteRecords =
getValueSitesForKind(ValueKind);
for (uint32_t I = 0; I < ThisNumValueSites; I++)
ThisSiteRecords[I].scale(SIPE, Weight);
for (auto &R : getValueSitesForKind(ValueKind))
R.scale(SIPE, Weight);
}
void InstrProfRecord::scale(uint64_t Weight) {
@@ -583,7 +582,7 @@ void InstrProfRecord::addValueData(uint32_t ValueKind, uint32_t Site,
VData[I].Value = remapValue(VData[I].Value, ValueKind, ValueMap);
}
std::vector<InstrProfValueSiteRecord> &ValueSites =
getValueSitesForKind(ValueKind);
getOrCreateValueSitesForKind(ValueKind);
if (N == 0)
ValueSites.emplace_back();
else