Reduce Partial LSE memory usage.
Instantiate ExecutionSubgraph only for partial singleton
candidates (currently NewInstance, possibly NewArray in the
future). This reduces "LSA" allocations.
Reserve memory for PartialLoadStoreEliminationHelper members
based on the number of partial singletons instead of the
number of reference infos. This reduces "LSE" allocations.
The peak scoped arena allocation for one compiled method
is reduced from
MEM: used: 97424004, allocated: 99006568, lost: 1115968
LSA 46015104
LSE 51408900
down to
MEM: used: 17000744, allocated: 26713880, lost: 3332496
GVN 17000744
where the LSA+LSE memory use is lower than GVN use.
Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 33650849
Change-Id: I323b9f144b258f0fab034794770971547ce94b59
diff --git a/compiler/optimizing/load_store_elimination.cc b/compiler/optimizing/load_store_elimination.cc
index d7cae76..722cc83 100644
--- a/compiler/optimizing/load_store_elimination.cc
+++ b/compiler/optimizing/load_store_elimination.cc
@@ -617,10 +617,13 @@
bool IsPartialNoEscape(HBasicBlock* blk, size_t idx) {
auto* ri = heap_location_collector_.GetHeapLocation(idx)->GetReferenceInfo();
- auto* sg = ri->GetNoEscapeSubgraph();
- return ri->IsPartialSingleton() &&
- std::none_of(sg->GetExcludedCohorts().cbegin(),
- sg->GetExcludedCohorts().cend(),
+ if (!ri->IsPartialSingleton()) {
+ return false;
+ }
+ ArrayRef<const ExecutionSubgraph::ExcludedCohort> cohorts =
+ ri->GetNoEscapeSubgraph()->GetExcludedCohorts();
+ return std::none_of(cohorts.cbegin(),
+ cohorts.cend(),
[&](const ExecutionSubgraph::ExcludedCohort& ex) -> bool {
// Make sure we haven't yet and never will escape.
return ex.PrecedesBlock(blk) ||
@@ -1096,8 +1099,6 @@
heap_values_for_[instruction->GetBlock()->GetBlockId()];
for (size_t i = 0u, size = heap_values.size(); i != size; ++i) {
ReferenceInfo* ref_info = heap_location_collector_.GetHeapLocation(i)->GetReferenceInfo();
- ArrayRef<const ExecutionSubgraph::ExcludedCohort> cohorts =
- ref_info->GetNoEscapeSubgraph()->GetExcludedCohorts();
HBasicBlock* blk = instruction->GetBlock();
// We don't need to do anything if the reference has not escaped at this point.
// This is true if either we (1) never escape or (2) sometimes escape but
@@ -1105,14 +1106,22 @@
// We count being in the excluded cohort as escaping. Technically, this is
// a bit over-conservative (since we can have multiple non-escaping calls
// before a single escaping one) but this simplifies everything greatly.
+ auto partial_singleton_did_not_escape = [](ReferenceInfo* ref_info, HBasicBlock* blk) {
+ DCHECK(ref_info->IsPartialSingleton());
+ if (!ref_info->GetNoEscapeSubgraph()->ContainsBlock(blk)) {
+ return false;
+ }
+ ArrayRef<const ExecutionSubgraph::ExcludedCohort> cohorts =
+ ref_info->GetNoEscapeSubgraph()->GetExcludedCohorts();
+ return std::none_of(cohorts.begin(),
+ cohorts.end(),
+ [&](const ExecutionSubgraph::ExcludedCohort& cohort) {
+ return cohort.PrecedesBlock(blk);
+ });
+ };
if (ref_info->IsSingleton() ||
// partial and we aren't currently escaping and we haven't escaped yet.
- (ref_info->IsPartialSingleton() && ref_info->GetNoEscapeSubgraph()->ContainsBlock(blk) &&
- std::none_of(cohorts.begin(),
- cohorts.end(),
- [&](const ExecutionSubgraph::ExcludedCohort& cohort) {
- return cohort.PrecedesBlock(blk);
- }))) {
+ (ref_info->IsPartialSingleton() && partial_singleton_did_not_escape(ref_info, blk))) {
// Singleton references cannot be seen by the callee.
} else {
if (side_effects.DoesAnyRead() || side_effects.DoesAnyWrite()) {
@@ -2901,9 +2910,9 @@
nullptr,
alloc_->Adapter(kArenaAllocLSE)),
first_materialization_block_id_(GetGraph()->GetBlocks().size()) {
- heap_refs_.reserve(lse_->heap_location_collector_.GetNumberOfReferenceInfos());
- new_ref_phis_.reserve(lse_->heap_location_collector_.GetNumberOfReferenceInfos() *
- GetGraph()->GetBlocks().size());
+ size_t num_partial_singletons = lse_->heap_location_collector_.CountPartialSingletons();
+ heap_refs_.reserve(num_partial_singletons);
+ new_ref_phis_.reserve(num_partial_singletons * GetGraph()->GetBlocks().size());
CollectInterestingHeapRefs();
}