Avoid allocating OatFile::OatClass on the heap.
Avoid allocating a BitVector for OatFile::OatClass::bitmap_
with kOatClassSomeCompiled methods. That makes the OatClass
copy-constructible as it doesn't own any memory. We use that
in OatFile::OatDexFile::GetOatClass() to return the result
by value thus avoiding one or two heap allocations per call.
Change-Id: Ic7098109028a5b49e39ef626f877de86e732ed18
diff --git a/runtime/base/bit_vector.cc b/runtime/base/bit_vector.cc
index 590835e..d8ef962 100644
--- a/runtime/base/bit_vector.cc
+++ b/runtime/base/bit_vector.cc
@@ -65,8 +65,7 @@
return false;
}
- uint32_t val = storage_[num >> 5] & check_masks[num & 0x1f];
- return (val != 0);
+ return IsBitSet(storage_, num);
}
// Mark all bits bit as "clear".
@@ -213,27 +212,10 @@
return count;
}
-// Count the number of bits that are set up through and including num.
-uint32_t BitVector::NumSetBits(uint32_t num) const {
- DCHECK_LT(num, storage_size_ * sizeof(*storage_) * 8);
- uint32_t last_word = num >> 5;
- uint32_t partial_word_bits = num & 0x1f;
-
- // partial_word_bits | # | | | partial_word_mask
- // 00000 | 0 | 0xffffffff >> (31 - 0) | (1 << (0 + 1)) - 1 | 0x00000001
- // 00001 | 1 | 0xffffffff >> (31 - 1) | (1 << (1 + 1)) - 1 | 0x00000003
- // 00010 | 2 | 0xffffffff >> (31 - 2) | (1 << (2 + 1)) - 1 | 0x00000007
- // ..... |
- // 11110 | 30 | 0xffffffff >> (31 - 30) | (1 << (30 + 1)) - 1 | 0x7fffffff
- // 11111 | 31 | 0xffffffff >> (31 - 31) | last_full_word++ | 0xffffffff
- uint32_t partial_word_mask = 0xffffffff >> (0x1f - partial_word_bits);
-
- uint32_t count = 0;
- for (uint32_t word = 0; word < last_word; word++) {
- count += __builtin_popcount(storage_[word]);
- }
- count += __builtin_popcount(storage_[last_word] & partial_word_mask);
- return count;
+// Count the number of bits that are set in range [0, end).
+uint32_t BitVector::NumSetBits(uint32_t end) const {
+ DCHECK_LE(end, storage_size_ * sizeof(*storage_) * 8);
+ return NumSetBits(storage_, end);
}
BitVector::Iterator* BitVector::GetIterator() const {
@@ -327,4 +309,23 @@
}
}
+bool BitVector::IsBitSet(const uint32_t* storage, uint32_t num) {
+ uint32_t val = storage[num >> 5] & check_masks[num & 0x1f];
+ return (val != 0);
+}
+
+uint32_t BitVector::NumSetBits(const uint32_t* storage, uint32_t end) {
+ uint32_t word_end = end >> 5;
+ uint32_t partial_word_bits = end & 0x1f;
+
+ uint32_t count = 0u;
+ for (uint32_t word = 0u; word < word_end; word++) {
+ count += __builtin_popcount(storage[word]);
+ }
+ if (partial_word_bits != 0u) {
+ count += __builtin_popcount(storage[word_end] & ~(0xffffffffu << partial_word_bits));
+ }
+ return count;
+}
+
} // namespace art
diff --git a/runtime/base/bit_vector.h b/runtime/base/bit_vector.h
index c8f285e..a496dbd 100644
--- a/runtime/base/bit_vector.h
+++ b/runtime/base/bit_vector.h
@@ -119,7 +119,9 @@
bool SameBitsSet(const BitVector *src);
uint32_t NumSetBits() const;
- uint32_t NumSetBits(uint32_t num) const;
+
+ // Number of bits set in range [0, end).
+ uint32_t NumSetBits(uint32_t end) const;
Iterator* GetIterator() const;
@@ -135,6 +137,11 @@
*/
int GetHighestBitSet() const;
+ // Is bit set in storage. (No range check.)
+ static bool IsBitSet(const uint32_t* storage, uint32_t num);
+ // Number of bits set in range [0, end) in storage. (No range check.)
+ static uint32_t NumSetBits(const uint32_t* storage, uint32_t end);
+
private:
Allocator* const allocator_;
const bool expandable_; // expand bitmap if we run out?
diff --git a/runtime/base/bit_vector_test.cc b/runtime/base/bit_vector_test.cc
index a67fb33..2ff55cb 100644
--- a/runtime/base/bit_vector_test.cc
+++ b/runtime/base/bit_vector_test.cc
@@ -29,8 +29,8 @@
EXPECT_FALSE(bv.IsExpandable());
EXPECT_EQ(0U, bv.NumSetBits());
- EXPECT_EQ(0U, bv.NumSetBits(0));
- EXPECT_EQ(0U, bv.NumSetBits(kBits - 1));
+ EXPECT_EQ(0U, bv.NumSetBits(1));
+ EXPECT_EQ(0U, bv.NumSetBits(kBits));
for (size_t i = 0; i < kBits; i++) {
EXPECT_FALSE(bv.IsBitSet(i));
}
@@ -46,8 +46,8 @@
bv.SetBit(0);
bv.SetBit(kBits - 1);
EXPECT_EQ(2U, bv.NumSetBits());
- EXPECT_EQ(1U, bv.NumSetBits(0));
- EXPECT_EQ(2U, bv.NumSetBits(kBits - 1));
+ EXPECT_EQ(1U, bv.NumSetBits(1));
+ EXPECT_EQ(2U, bv.NumSetBits(kBits));
EXPECT_TRUE(bv.IsBitSet(0));
for (size_t i = 1; i < kBits - 1; i++) {
EXPECT_FALSE(bv.IsBitSet(i));
@@ -98,25 +98,25 @@
EXPECT_EQ(0x00010001U, bv.GetRawStorageWord(1));
EXPECT_EQ(4U, bv.NumSetBits());
- EXPECT_EQ(0U, bv.NumSetBits(0));
+ EXPECT_EQ(0U, bv.NumSetBits(1));
- EXPECT_EQ(0U, bv.NumSetBits(7));
- EXPECT_EQ(1U, bv.NumSetBits(8));
+ EXPECT_EQ(0U, bv.NumSetBits(8));
EXPECT_EQ(1U, bv.NumSetBits(9));
+ EXPECT_EQ(1U, bv.NumSetBits(10));
- EXPECT_EQ(1U, bv.NumSetBits(15));
- EXPECT_EQ(2U, bv.NumSetBits(16));
+ EXPECT_EQ(1U, bv.NumSetBits(16));
EXPECT_EQ(2U, bv.NumSetBits(17));
+ EXPECT_EQ(2U, bv.NumSetBits(18));
- EXPECT_EQ(2U, bv.NumSetBits(31));
- EXPECT_EQ(3U, bv.NumSetBits(32));
+ EXPECT_EQ(2U, bv.NumSetBits(32));
EXPECT_EQ(3U, bv.NumSetBits(33));
+ EXPECT_EQ(3U, bv.NumSetBits(34));
- EXPECT_EQ(3U, bv.NumSetBits(47));
- EXPECT_EQ(4U, bv.NumSetBits(48));
+ EXPECT_EQ(3U, bv.NumSetBits(48));
EXPECT_EQ(4U, bv.NumSetBits(49));
+ EXPECT_EQ(4U, bv.NumSetBits(50));
- EXPECT_EQ(4U, bv.NumSetBits(63));
+ EXPECT_EQ(4U, bv.NumSetBits(64));
}
TEST(BitVector, SetInitialBits) {