Create a scoped arena allocator and use that for LVN.
This saves more than 0.5s of boot.oat compilation time
on Nexus 5.
TODO: Move other stuff to the scoped allocator. This CL
alone increases the peak memory allocation. By reusing
the memory for other parts of the compilation we should
reduce this overhead.
Change-Id: Ifbc00aab4f3afd0000da818dfe68b96713824a08
diff --git a/compiler/utils/scoped_arena_allocator.cc b/compiler/utils/scoped_arena_allocator.cc
new file mode 100644
index 0000000..ee3b07e
--- /dev/null
+++ b/compiler/utils/scoped_arena_allocator.cc
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "scoped_arena_allocator.h"
+
+#include "utils/arena_allocator.h"
+#include <memcheck/memcheck.h>
+
+namespace art {
+
+static constexpr size_t kValgrindRedZoneBytes = 8;
+
+ArenaStack::ArenaStack(ArenaPool* arena_pool)
+ : DebugStackRefCounter(),
+ stats_and_pool_(arena_pool),
+ bottom_arena_(nullptr),
+ top_arena_(nullptr),
+ top_ptr_(nullptr),
+ top_end_(nullptr),
+ running_on_valgrind_(RUNNING_ON_VALGRIND > 0) {
+}
+
+ArenaStack::~ArenaStack() {
+ stats_and_pool_.pool->FreeArenaChain(bottom_arena_);
+}
+
+MemStats ArenaStack::GetPeakStats() const {
+ DebugStackRefCounter::CheckNoRefs();
+ return MemStats("ArenaStack peak", static_cast<const TaggedStats<Peak>*>(&stats_and_pool_),
+ bottom_arena_);
+}
+
+uint8_t* ArenaStack::AllocateFromNextArena(size_t rounded_bytes) {
+ UpdateBytesAllocated();
+ size_t allocation_size = std::max(Arena::kDefaultSize, rounded_bytes);
+ if (UNLIKELY(top_arena_ == nullptr)) {
+ top_arena_ = bottom_arena_ = stats_and_pool_.pool->AllocArena(allocation_size);
+ top_arena_->next_ = nullptr;
+ } else if (top_arena_->next_ != nullptr && top_arena_->next_->Size() >= allocation_size) {
+ top_arena_ = top_arena_->next_;
+ } else {
+ Arena* tail = top_arena_->next_;
+ top_arena_->next_ = stats_and_pool_.pool->AllocArena(allocation_size);
+ top_arena_ = top_arena_->next_;
+ top_arena_->next_ = tail;
+ }
+ top_end_ = top_arena_->End();
+ // top_ptr_ shall be updated by ScopedArenaAllocator.
+ return top_arena_->Begin();
+}
+
+void ArenaStack::UpdatePeakStatsAndRestore(const ArenaAllocatorStats& restore_stats) {
+ if (PeakStats()->BytesAllocated() < CurrentStats()->BytesAllocated()) {
+ PeakStats()->Copy(*CurrentStats());
+ }
+ CurrentStats()->Copy(restore_stats);
+}
+
+void ArenaStack::UpdateBytesAllocated() {
+ if (top_arena_ != nullptr) {
+ // Update how many bytes we have allocated into the arena so that the arena pool knows how
+ // much memory to zero out. Though ScopedArenaAllocator doesn't guarantee the memory is
+ // zero-initialized, the Arena may be reused by ArenaAllocator which does guarantee this.
+ size_t allocated = static_cast<size_t>(top_ptr_ - top_arena_->Begin());
+ if (top_arena_->bytes_allocated_ < allocated) {
+ top_arena_->bytes_allocated_ = allocated;
+ }
+ }
+}
+
+void* ArenaStack::AllocValgrind(size_t bytes, ArenaAllocKind kind) {
+ size_t rounded_bytes = (bytes + kValgrindRedZoneBytes + 3) & ~3;
+ uint8_t* ptr = top_ptr_;
+ if (UNLIKELY(static_cast<size_t>(top_end_ - ptr) < rounded_bytes)) {
+ ptr = AllocateFromNextArena(rounded_bytes);
+ }
+ CurrentStats()->RecordAlloc(bytes, kind);
+ top_ptr_ = ptr + rounded_bytes;
+ VALGRIND_MAKE_MEM_NOACCESS(ptr + bytes, rounded_bytes - bytes);
+ return ptr;
+}
+
+ScopedArenaAllocator::ScopedArenaAllocator(ArenaStack* arena_stack)
+ : DebugStackReference(arena_stack),
+ DebugStackRefCounter(),
+ ArenaAllocatorStats(*arena_stack->CurrentStats()),
+ arena_stack_(arena_stack),
+ mark_arena_(arena_stack->top_arena_),
+ mark_ptr_(arena_stack->top_ptr_),
+ mark_end_(arena_stack->top_end_) {
+}
+
+ScopedArenaAllocator::~ScopedArenaAllocator() {
+ Reset();
+}
+
+void ScopedArenaAllocator::Reset() {
+ DebugStackReference::CheckTop();
+ DebugStackRefCounter::CheckNoRefs();
+ arena_stack_->UpdatePeakStatsAndRestore(*this);
+ arena_stack_->UpdateBytesAllocated();
+ if (LIKELY(mark_arena_ != nullptr)) {
+ arena_stack_->top_arena_ = mark_arena_;
+ arena_stack_->top_ptr_ = mark_ptr_;
+ arena_stack_->top_end_ = mark_end_;
+ } else if (arena_stack_->bottom_arena_ != nullptr) {
+ mark_arena_ = arena_stack_->top_arena_ = arena_stack_->bottom_arena_;
+ mark_ptr_ = arena_stack_->top_ptr_ = mark_arena_->Begin();
+ mark_end_ = arena_stack_->top_end_ = mark_arena_->End();
+ }
+}
+
+} // namespace art