Omit OatMethodOffsets for classes without compiled code

Change-Id: If0d290f4aebc778ff12d8fed017c270ad2ac3220

13 files changed, 668 insertions, 21 deletions

diff --git a/runtime/Android.mk b/runtime/Android.mk
index 8579222..e4b7e47 100644
--- a/runtime/Android.mk
+++ b/runtime/Android.mk
@@ -21,6 +21,8 @@ include art/build/Android.common.mk
 LIBART_COMMON_SRC_FILES := \
 	atomic.cc.arm \
 	barrier.cc \
+	base/allocator.cc \
+	base/bit_vector.cc \
 	base/logging.cc \
 	base/mutex.cc \
 	base/stringpiece.cc \
@@ -247,6 +249,7 @@ LIBART_ENUM_OPERATOR_OUT_HEADER_FILES := \
 	locks.h \
 	lock_word.h \
 	mirror/class.h \
+	oat.h \
 	thread.h \
 	thread_state.h \
 	verifier/method_verifier.h
diff --git a/runtime/base/allocator.cc b/runtime/base/allocator.cc
new file mode 100644
index 0000000..4f7753d
--- /dev/null
+++ b/runtime/base/allocator.cc
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2013 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 "allocator.h"
+
+#include <inttypes.h>
+#include <stdlib.h>
+
+#include "base/logging.h"
+
+namespace art {
+
+class MallocAllocator : public Allocator {
+ public:
+  explicit MallocAllocator() {}
+  ~MallocAllocator() {}
+
+  virtual void* Alloc(size_t size) {
+    return calloc(sizeof(uint8_t), size);
+  }
+
+  virtual void Free(void* p) {
+    free(p);
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MallocAllocator);
+};
+
+MallocAllocator g_malloc_allocator;
+
+class NoopAllocator : public Allocator {
+ public:
+  explicit NoopAllocator() {}
+  ~NoopAllocator() {}
+
+  virtual void* Alloc(size_t size) {
+    LOG(FATAL) << "NoopAllocator::Alloc should not be called";
+    return NULL;
+  }
+
+  virtual void Free(void* p) {
+    // Noop.
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(NoopAllocator);
+};
+
+NoopAllocator g_noop_allocator;
+
+Allocator* Allocator::GetMallocAllocator() {
+  return &g_malloc_allocator;
+}
+
+Allocator* Allocator::GetNoopAllocator() {
+  return &g_noop_allocator;
+}
+
+
+}  // namespace art
diff --git a/runtime/base/allocator.h b/runtime/base/allocator.h
new file mode 100644
index 0000000..917bf0b
--- /dev/null
+++ b/runtime/base/allocator.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef ART_RUNTIME_BASE_ALLOCATOR_H_
+#define ART_RUNTIME_BASE_ALLOCATOR_H_
+
+#include "base/macros.h"
+
+namespace art {
+
+class Allocator {
+ public:
+  static Allocator* GetMallocAllocator();
+  static Allocator* GetNoopAllocator();
+
+  Allocator() {}
+  virtual ~Allocator() {}
+
+  virtual void* Alloc(size_t) = 0;
+  virtual void Free(void*) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(Allocator);
+};
+
+}  // namespace art
+
+#endif  // ART_RUNTIME_BASE_ALLOCATOR_H_
diff --git a/runtime/base/bit_vector.cc b/runtime/base/bit_vector.cc
new file mode 100644
index 0000000..3b82651
--- /dev/null
+++ b/runtime/base/bit_vector.cc
@@ -0,0 +1,177 @@
+/*
+ * Copyright (C) 2011 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 "bit_vector.h"
+
+namespace art {
+
+// TODO: profile to make sure this is still a win relative to just using shifted masks.
+static uint32_t check_masks[32] = {
+  0x00000001, 0x00000002, 0x00000004, 0x00000008, 0x00000010,
+  0x00000020, 0x00000040, 0x00000080, 0x00000100, 0x00000200,
+  0x00000400, 0x00000800, 0x00001000, 0x00002000, 0x00004000,
+  0x00008000, 0x00010000, 0x00020000, 0x00040000, 0x00080000,
+  0x00100000, 0x00200000, 0x00400000, 0x00800000, 0x01000000,
+  0x02000000, 0x04000000, 0x08000000, 0x10000000, 0x20000000,
+  0x40000000, 0x80000000 };
+
+static inline uint32_t BitsToWords(uint32_t bits) {
+  return (bits + 31) >> 5;
+}
+
+// TODO: replace excessive argument defaulting when we are at gcc 4.7
+// or later on host with delegating constructor support. Specifically,
+// starts_bits and storage_size/storage are mutually exclusive.
+BitVector::BitVector(uint32_t start_bits,
+                     bool expandable,
+                     Allocator* allocator,
+                     uint32_t storage_size,
+                     uint32_t* storage)
+  : allocator_(allocator),
+    expandable_(expandable),
+    storage_size_(storage_size),
+    storage_(storage) {
+  DCHECK_EQ(sizeof(storage_[0]), 4U);  // Assuming 32-bit units.
+  if (storage_ == NULL) {
+    storage_size_ = BitsToWords(start_bits);
+    storage_ = static_cast<uint32_t*>(allocator_->Alloc(storage_size_ * sizeof(uint32_t)));
+  }
+}
+
+BitVector::~BitVector() {
+  allocator_->Free(storage_);
+}
+
+/*
+ * Determine whether or not the specified bit is set.
+ */
+bool BitVector::IsBitSet(uint32_t num) const {
+  DCHECK_LT(num, storage_size_ * sizeof(uint32_t) * 8);
+
+  uint32_t val = storage_[num >> 5] & check_masks[num & 0x1f];
+  return (val != 0);
+}
+
+// Mark all bits bit as "clear".
+void BitVector::ClearAllBits() {
+  memset(storage_, 0, storage_size_ * sizeof(uint32_t));
+}
+
+// Mark the specified bit as "set".
+/*
+ * TUNING: this could have pathologically bad growth/expand behavior.  Make sure we're
+ * not using it badly or change resize mechanism.
+ */
+void BitVector::SetBit(uint32_t num) {
+  if (num >= storage_size_ * sizeof(uint32_t) * 8) {
+    DCHECK(expandable_) << "Attempted to expand a non-expandable bitmap to position " << num;
+
+    /* Round up to word boundaries for "num+1" bits */
+    uint32_t new_size = BitsToWords(num + 1);
+    DCHECK_GT(new_size, storage_size_);
+    uint32_t *new_storage =
+        static_cast<uint32_t*>(allocator_->Alloc(new_size * sizeof(uint32_t)));
+    memcpy(new_storage, storage_, storage_size_ * sizeof(uint32_t));
+    // Zero out the new storage words.
+    memset(&new_storage[storage_size_], 0, (new_size - storage_size_) * sizeof(uint32_t));
+    // TOTO: collect stats on space wasted because of resize.
+    storage_ = new_storage;
+    storage_size_ = new_size;
+  }
+
+  storage_[num >> 5] |= check_masks[num & 0x1f];
+}
+
+// Mark the specified bit as "unset".
+void BitVector::ClearBit(uint32_t num) {
+  DCHECK_LT(num, storage_size_ * sizeof(uint32_t) * 8);
+  storage_[num >> 5] &= ~check_masks[num & 0x1f];
+}
+
+// Intersect with another bit vector.  Sizes and expandability must be the same.
+void BitVector::Intersect(const BitVector* src) {
+  DCHECK_EQ(storage_size_, src->GetStorageSize());
+  DCHECK_EQ(expandable_, src->IsExpandable());
+  for (uint32_t idx = 0; idx < storage_size_; idx++) {
+    storage_[idx] &= src->GetRawStorageWord(idx);
+  }
+}
+
+/*
+ * Union with another bit vector.  Sizes and expandability must be the same.
+ */
+void BitVector::Union(const BitVector* src) {
+  DCHECK_EQ(storage_size_, src->GetStorageSize());
+  DCHECK_EQ(expandable_, src->IsExpandable());
+  for (uint32_t idx = 0; idx < storage_size_; idx++) {
+    storage_[idx] |= src->GetRawStorageWord(idx);
+  }
+}
+
+// Count the number of bits that are set.
+uint32_t BitVector::NumSetBits() const {
+  uint32_t count = 0;
+  for (uint32_t word = 0; word < storage_size_; word++) {
+    count += __builtin_popcount(storage_[word]);
+  }
+  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(uint32_t) * 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;
+}
+
+BitVector::Iterator* BitVector::GetIterator() const {
+  return new (allocator_) Iterator(this);
+}
+
+/*
+ * Mark specified number of bits as "set". Cannot set all bits like ClearAll
+ * since there might be unused bits - setting those to one will confuse the
+ * iterator.
+ */
+void BitVector::SetInitialBits(uint32_t num_bits) {
+  DCHECK_LE(BitsToWords(num_bits), storage_size_);
+  uint32_t idx;
+  for (idx = 0; idx < (num_bits >> 5); idx++) {
+    storage_[idx] = -1;
+  }
+  uint32_t rem_num_bits = num_bits & 0x1f;
+  if (rem_num_bits) {
+    storage_[idx] = (1 << rem_num_bits) - 1;
+  }
+}
+
+}  // namespace art
diff --git a/runtime/base/bit_vector.h b/runtime/base/bit_vector.h
new file mode 100644
index 0000000..74bec08
--- /dev/null
+++ b/runtime/base/bit_vector.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef ART_RUNTIME_BASE_BIT_VECTOR_H_
+#define ART_RUNTIME_BASE_BIT_VECTOR_H_
+
+#include <stdint.h>
+#include <stddef.h>
+
+#include "allocator.h"
+#include "base/logging.h"
+#include "utils.h"
+
+namespace art {
+
+/*
+ * Expanding bitmap, used for tracking resources.  Bits are numbered starting
+ * from zero.  All operations on a BitVector are unsynchronized.
+ */
+class BitVector {
+  public:
+    class Iterator {
+      public:
+        explicit Iterator(const BitVector* bit_vector)
+          : p_bits_(bit_vector),
+            bit_storage_(bit_vector->GetRawStorage()),
+            bit_index_(0),
+            bit_size_(p_bits_->storage_size_ * sizeof(uint32_t) * 8) {}
+
+        // Return the position of the next set bit.  -1 means end-of-element reached.
+        int32_t Next() {
+          // Did anything obviously change since we started?
+          DCHECK_EQ(bit_size_, p_bits_->GetStorageSize() * sizeof(uint32_t) * 8);
+          DCHECK_EQ(bit_storage_, p_bits_->GetRawStorage());
+
+          if (UNLIKELY(bit_index_ >= bit_size_)) return -1;
+
+          uint32_t word_index = bit_index_ / 32;
+          uint32_t word = bit_storage_[word_index];
+          // Mask out any bits in the first word we've already considered.
+          word >>= bit_index_ & 0x1f;
+          if (word == 0) {
+            bit_index_ &= ~0x1f;
+            do {
+              word_index++;
+              if (UNLIKELY((word_index * 32) >= bit_size_)) {
+                bit_index_ = bit_size_;
+                return -1;
+              }
+              word = bit_storage_[word_index];
+              bit_index_ += 32;
+            } while (word == 0);
+          }
+          bit_index_ += CTZ(word) + 1;
+          return bit_index_ - 1;
+        }
+
+        static void* operator new(size_t size, Allocator* allocator) {
+          return allocator->Alloc(sizeof(BitVector::Iterator));
+        };
+        static void operator delete(void* p) {
+          Iterator* it = reinterpret_cast<Iterator*>(p);
+          it->p_bits_->allocator_->Free(p);
+        }
+
+      private:
+        const BitVector* const p_bits_;
+        const uint32_t* const bit_storage_;
+        uint32_t bit_index_;           // Current index (size in bits).
+        const uint32_t bit_size_;      // Size of vector in bits.
+
+        friend class BitVector;
+    };
+
+    BitVector(uint32_t start_bits,
+              bool expandable,
+              Allocator* allocator,
+              uint32_t storage_size = 0,
+              uint32_t* storage = NULL);
+
+    virtual ~BitVector();
+
+    void SetBit(uint32_t num);
+    void ClearBit(uint32_t num);
+    bool IsBitSet(uint32_t num) const;
+    void ClearAllBits();
+    void SetInitialBits(uint32_t num_bits);
+    void Copy(BitVector* src) {
+      memcpy(storage_, src->GetRawStorage(), sizeof(uint32_t) * storage_size_);
+    }
+    void Intersect(const BitVector* src2);
+    void Union(const BitVector* src);
+    // Are we equal to another bit vector?  Note: expandability attributes must also match.
+    bool Equal(const BitVector* src) {
+      return (storage_size_ == src->GetStorageSize()) &&
+        (expandable_ == src->IsExpandable()) &&
+        (memcmp(storage_, src->GetRawStorage(), storage_size_ * sizeof(uint32_t)) == 0);
+    }
+    uint32_t NumSetBits() const;
+    uint32_t NumSetBits(uint32_t num) const;
+
+    Iterator* GetIterator() const;
+
+    uint32_t GetStorageSize() const { return storage_size_; }
+    bool IsExpandable() const { return expandable_; }
+    uint32_t GetRawStorageWord(size_t idx) const { return storage_[idx]; }
+    uint32_t* GetRawStorage() { return storage_; }
+    const uint32_t* GetRawStorage() const { return storage_; }
+    size_t GetSizeOf() const { return storage_size_ * sizeof(uint32_t); }
+
+  private:
+    Allocator* const allocator_;
+    const bool expandable_;         // expand bitmap if we run out?
+    uint32_t   storage_size_;       // current size, in 32-bit words.
+    uint32_t*  storage_;
+};
+
+
+}  // namespace art
+
+#endif  // ART_RUNTIME_BASE_BIT_VECTOR_H_
diff --git a/runtime/base/bit_vector_test.cc b/runtime/base/bit_vector_test.cc
new file mode 100644
index 0000000..d99d059
--- /dev/null
+++ b/runtime/base/bit_vector_test.cc
@@ -0,0 +1,122 @@
+/*
+ * Copyright (C) 2013 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 "UniquePtr.h"
+#include "bit_vector.h"
+#include "gtest/gtest.h"
+
+namespace art {
+
+TEST(BitVector, Test) {
+  const size_t kBits = 32;
+
+  BitVector bv(kBits, false, Allocator::GetMallocAllocator());
+  EXPECT_EQ(1U, bv.GetStorageSize());
+  EXPECT_EQ(kWordSize, bv.GetSizeOf());
+  EXPECT_FALSE(bv.IsExpandable());
+
+  EXPECT_EQ(0U, bv.NumSetBits());
+  EXPECT_EQ(0U, bv.NumSetBits(0));
+  EXPECT_EQ(0U, bv.NumSetBits(kBits - 1));
+  for (size_t i = 0; i < kBits; i++) {
+    EXPECT_FALSE(bv.IsBitSet(i));
+  }
+  EXPECT_EQ(0U, bv.GetRawStorageWord(0));
+  EXPECT_EQ(0U, *bv.GetRawStorage());
+
+  BitVector::Iterator empty_iterator(&bv);
+  EXPECT_EQ(-1, empty_iterator.Next());
+
+  UniquePtr<BitVector::Iterator> empty_iterator_on_heap(bv.GetIterator());
+  EXPECT_EQ(-1, empty_iterator_on_heap->Next());
+
+  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_TRUE(bv.IsBitSet(0));
+  for (size_t i = 1; i < kBits - 1; i++) {
+    EXPECT_FALSE(bv.IsBitSet(i));
+  }
+  EXPECT_TRUE(bv.IsBitSet(kBits - 1));
+  EXPECT_EQ(0x80000001U, bv.GetRawStorageWord(0));
+  EXPECT_EQ(0x80000001U, *bv.GetRawStorage());
+
+  BitVector::Iterator iterator(&bv);
+  EXPECT_EQ(0, iterator.Next());
+  EXPECT_EQ(static_cast<int>(kBits - 1), iterator.Next());
+  EXPECT_EQ(-1, iterator.Next());
+}
+
+TEST(BitVector, NoopAllocator) {
+  const uint32_t kWords = 2;
+
+  uint32_t bits[kWords];
+  memset(bits, 0, sizeof(bits));
+
+  BitVector bv(0U, false, Allocator::GetNoopAllocator(), kWords, bits);
+  EXPECT_EQ(kWords, bv.GetStorageSize());
+  EXPECT_EQ(kWords * kWordSize, bv.GetSizeOf());
+  EXPECT_EQ(bits, bv.GetRawStorage());
+  EXPECT_EQ(0U, bv.NumSetBits());
+
+  bv.SetBit(8);
+  EXPECT_EQ(1U, bv.NumSetBits());
+  EXPECT_EQ(0x00000100U, bv.GetRawStorageWord(0));
+  EXPECT_EQ(0x00000000U, bv.GetRawStorageWord(1));
+  EXPECT_EQ(1U, bv.NumSetBits());
+
+  bv.SetBit(16);
+  EXPECT_EQ(2U, bv.NumSetBits());
+  EXPECT_EQ(0x00010100U, bv.GetRawStorageWord(0));
+  EXPECT_EQ(0x00000000U, bv.GetRawStorageWord(1));
+  EXPECT_EQ(2U, bv.NumSetBits());
+
+  bv.SetBit(32);
+  EXPECT_EQ(3U, bv.NumSetBits());
+  EXPECT_EQ(0x00010100U, bv.GetRawStorageWord(0));
+  EXPECT_EQ(0x00000001U, bv.GetRawStorageWord(1));
+  EXPECT_EQ(3U, bv.NumSetBits());
+
+  bv.SetBit(48);
+  EXPECT_EQ(4U, bv.NumSetBits());
+  EXPECT_EQ(0x00010100U, bv.GetRawStorageWord(0));
+  EXPECT_EQ(0x00010001U, bv.GetRawStorageWord(1));
+  EXPECT_EQ(4U, bv.NumSetBits());
+
+  EXPECT_EQ(0U, bv.NumSetBits(0));
+
+  EXPECT_EQ(0U, bv.NumSetBits(7));
+  EXPECT_EQ(1U, bv.NumSetBits(8));
+  EXPECT_EQ(1U, bv.NumSetBits(9));
+
+  EXPECT_EQ(1U, bv.NumSetBits(15));
+  EXPECT_EQ(2U, bv.NumSetBits(16));
+  EXPECT_EQ(2U, bv.NumSetBits(17));
+
+  EXPECT_EQ(2U, bv.NumSetBits(31));
+  EXPECT_EQ(3U, bv.NumSetBits(32));
+  EXPECT_EQ(3U, bv.NumSetBits(33));
+
+  EXPECT_EQ(3U, bv.NumSetBits(47));
+  EXPECT_EQ(4U, bv.NumSetBits(48));
+  EXPECT_EQ(4U, bv.NumSetBits(49));
+
+  EXPECT_EQ(4U, bv.NumSetBits(63));
+}
+
+}  // namespace art
diff --git a/runtime/exception_test.cc b/runtime/exception_test.cc
index 2e6b0a8..a5f9997 100644
--- a/runtime/exception_test.cc
+++ b/runtime/exception_test.cc
@@ -146,7 +146,7 @@ TEST_F(ExceptionTest, StackTraceElement) {
   ScopedObjectAccess soa(env);
 
   std::vector<uintptr_t> fake_stack;
-  ASSERT_EQ(kStackAlignment, 16);
+  ASSERT_EQ(kStackAlignment, 16U);
   ASSERT_EQ(sizeof(uintptr_t), sizeof(uint32_t));
 
 #if !defined(ART_USE_PORTABLE_COMPILER)
diff --git a/runtime/globals.h b/runtime/globals.h
index c397494..31574ff 100644
--- a/runtime/globals.h
+++ b/runtime/globals.h
@@ -30,30 +30,30 @@ const size_t KB = 1024;
 const size_t MB = KB * KB;
 const size_t GB = KB * KB * KB;
 
-const int kWordSize = sizeof(word);
-const int kPointerSize = sizeof(void*);
+const size_t kWordSize = sizeof(word);
+const size_t kPointerSize = sizeof(void*);
 
-const int kBitsPerByte = 8;
-const int kBitsPerByteLog2 = 3;
+const size_t kBitsPerByte = 8;
+const size_t kBitsPerByteLog2 = 3;
 const int kBitsPerWord = kWordSize * kBitsPerByte;
-const int kWordHighBitMask = 1 << (kBitsPerWord - 1);
+const size_t kWordHighBitMask = 1 << (kBitsPerWord - 1);
 
 // Required stack alignment
-const int kStackAlignment = 16;
+const size_t kStackAlignment = 16;
 
 // Required object alignment
-const int kObjectAlignment = 8;
+const size_t kObjectAlignment = 8;
 
 // ARM instruction alignment. ARM processors require code to be 4-byte aligned,
 // but ARM ELF requires 8..
-const int kArmAlignment = 8;
+const size_t kArmAlignment = 8;
 
 // MIPS instruction alignment.  MIPS processors require code to be 4-byte aligned.
 // TODO: Can this be 4?
-const int kMipsAlignment = 8;
+const size_t kMipsAlignment = 8;
 
 // X86 instruction alignment. This is the recommended alignment for maximum performance.
-const int kX86Alignment = 16;
+const size_t kX86Alignment = 16;
 
 // System page size. We check this against sysconf(_SC_PAGE_SIZE) at runtime, but use a simple
 // compile-time constant so the compiler can generate better code.
diff --git a/runtime/mirror/class.h b/runtime/mirror/class.h
index dbc6f57..d15f337 100644
--- a/runtime/mirror/class.h
+++ b/runtime/mirror/class.h
@@ -122,6 +122,7 @@ class MANAGED Class : public StaticStorageBase {
     kStatusVerified = 7,  // Logically part of linking; done pre-init.
     kStatusInitializing = 8,  // Class init in progress.
     kStatusInitialized = 9,  // Ready to go.
+    kStatusMax = 10,
   };
 
   Status GetStatus() const {
diff --git a/runtime/oat.cc b/runtime/oat.cc
index c01f77c..6fe5d10 100644
--- a/runtime/oat.cc
+++ b/runtime/oat.cc
@@ -22,7 +22,7 @@
 namespace art {
 
 const uint8_t OatHeader::kOatMagic[] = { 'o', 'a', 't', '\n' };
-const uint8_t OatHeader::kOatVersion[] = { '0', '0', '7', '\0' };
+const uint8_t OatHeader::kOatVersion[] = { '0', '0', '8', '\0' };
 
 OatHeader::OatHeader() {
   memset(this, 0, sizeof(*this));
diff --git a/runtime/oat.h b/runtime/oat.h
index a653cf8..a9dc540 100644
--- a/runtime/oat.h
+++ b/runtime/oat.h
@@ -104,6 +104,19 @@ class PACKED(4) OatHeader {
   DISALLOW_COPY_AND_ASSIGN(OatHeader);
 };
 
+// OatMethodOffsets are currently 7x32-bits=224-bits long, so if we can
+// save even one OatMethodOffsets struct, the more complicated encoding
+// using a bitmap pays for itself since few classes will have 224
+// methods.
+enum OatClassType {
+  kOatClassAllCompiled = 0,   // OatClass is followed by an OatMethodOffsets for each method.
+  kOatClassSomeCompiled = 1,  // A bitmap of which OatMethodOffsets are present follows the OatClass.
+  kOatClassNoneCompiled = 2,  // All methods are interpretted so no OatMethodOffsets are necessary.
+  kOatClassMax = 3,
+};
+
+std::ostream& operator<<(std::ostream& os, const OatClassType& rhs);
+
 class PACKED(4) OatMethodOffsets {
  public:
   OatMethodOffsets();
diff --git a/runtime/oat_file.cc b/runtime/oat_file.cc
index 7553dcc..fa2b485 100644
--- a/runtime/oat_file.cc
+++ b/runtime/oat_file.cc
@@ -18,6 +18,7 @@
 
 #include <dlfcn.h>
 
+#include "base/bit_vector.h"
 #include "base/stl_util.h"
 #include "base/unix_file/fd_file.h"
 #include "elf_file.h"
@@ -384,29 +385,92 @@ const OatFile::OatClass* OatFile::OatDexFile::GetOatClass(uint16_t class_def_ind
 
   const byte* oat_class_pointer = oat_file_->Begin() + oat_class_offset;
   CHECK_LT(oat_class_pointer, oat_file_->End()) << oat_file_->GetLocation();
-  mirror::Class::Status status = *reinterpret_cast<const mirror::Class::Status*>(oat_class_pointer);
 
-  const byte* methods_pointer = oat_class_pointer + sizeof(status);
+  const byte* status_pointer = oat_class_pointer;
+  CHECK_LT(status_pointer, oat_file_->End()) << oat_file_->GetLocation();
+  mirror::Class::Status status =
+      static_cast<mirror::Class::Status>(*reinterpret_cast<const int16_t*>(status_pointer));
+  CHECK_LT(status, mirror::Class::kStatusMax);
+
+  const byte* type_pointer = status_pointer + sizeof(uint16_t);
+  CHECK_LT(type_pointer, oat_file_->End()) << oat_file_->GetLocation();
+  OatClassType type = static_cast<OatClassType>(*reinterpret_cast<const uint16_t*>(type_pointer));
+  CHECK_LT(type, kOatClassMax);
+
+  const byte* bitmap_pointer = type_pointer + sizeof(int16_t);
+  CHECK_LT(bitmap_pointer, oat_file_->End()) << oat_file_->GetLocation();
+  uint32_t bitmap_size = 0;
+  if (type == kOatClassSomeCompiled) {
+    bitmap_size = static_cast<uint32_t>(*reinterpret_cast<const uint32_t*>(bitmap_pointer));
+    bitmap_pointer += sizeof(bitmap_size);
+    CHECK_LT(bitmap_pointer, oat_file_->End()) << oat_file_->GetLocation();
+  }
+
+  const byte* methods_pointer = bitmap_pointer + bitmap_size;
   CHECK_LT(methods_pointer, oat_file_->End()) << oat_file_->GetLocation();
 
   return new OatClass(oat_file_,
                       status,
+                      type,
+                      bitmap_size,
+                      reinterpret_cast<const uint32_t*>(bitmap_pointer),
                       reinterpret_cast<const OatMethodOffsets*>(methods_pointer));
 }
 
 OatFile::OatClass::OatClass(const OatFile* oat_file,
                             mirror::Class::Status status,
+                            OatClassType type,
+                            uint32_t bitmap_size,
+                            const uint32_t* bitmap_pointer,
                             const OatMethodOffsets* methods_pointer)
-    : oat_file_(oat_file), status_(status), methods_pointer_(methods_pointer) {}
-
-OatFile::OatClass::~OatClass() {}
+    : oat_file_(oat_file), status_(status), type_(type),
+      bitmap_(NULL), methods_pointer_(methods_pointer) {
+    switch (type_) {
+      case kOatClassAllCompiled: {
+        CHECK_EQ(0U, bitmap_size);
+        break;
+      }
+      case kOatClassSomeCompiled: {
+        CHECK_NE(0U, bitmap_size);
+        bitmap_ = new BitVector(0, false, Allocator::GetNoopAllocator(), bitmap_size,
+                                const_cast<uint32_t*>(bitmap_pointer));
+        break;
+      }
+      case kOatClassNoneCompiled: {
+        CHECK_EQ(0U, bitmap_size);
+        methods_pointer_ = NULL;
+        break;
+      }
+      case kOatClassMax: {
+        LOG(FATAL) << "Invalid OatClassType " << type_;
+        break;
+      }
+    }
+}
 
-mirror::Class::Status OatFile::OatClass::GetStatus() const {
-  return status_;
+OatFile::OatClass::~OatClass() {
+  delete bitmap_;
 }
 
 const OatFile::OatMethod OatFile::OatClass::GetOatMethod(uint32_t method_index) const {
-  const OatMethodOffsets& oat_method_offsets = methods_pointer_[method_index];
+  if (methods_pointer_ == NULL) {
+    CHECK_EQ(kOatClassNoneCompiled, type_);
+    return OatMethod(NULL, 0, 0, 0, 0, 0, 0, 0);
+  }
+  size_t methods_pointer_index;
+  if (bitmap_ == NULL) {
+    CHECK_EQ(kOatClassAllCompiled, type_);
+    methods_pointer_index = method_index;
+  } else {
+    CHECK_EQ(kOatClassSomeCompiled, type_);
+    if (!bitmap_->IsBitSet(method_index)) {
+      return OatMethod(NULL, 0, 0, 0, 0, 0, 0, 0);
+    }
+    size_t num_set_bits = bitmap_->NumSetBits(method_index);
+    CHECK_NE(0U, num_set_bits);
+    methods_pointer_index = num_set_bits - 1;
+  }
+  const OatMethodOffsets& oat_method_offsets = methods_pointer_[methods_pointer_index];
   return OatMethod(
       oat_file_->Begin(),
       oat_method_offsets.code_offset_,
diff --git a/runtime/oat_file.h b/runtime/oat_file.h
index af14760..887a9d1 100644
--- a/runtime/oat_file.h
+++ b/runtime/oat_file.h
@@ -29,6 +29,7 @@
 
 namespace art {
 
+class BitVector;
 class ElfFile;
 class MemMap;
 class OatMethodOffsets;
@@ -145,7 +146,13 @@ class OatFile {
 
   class OatClass {
    public:
-    mirror::Class::Status GetStatus() const;
+    mirror::Class::Status GetStatus() const {
+      return status_;
+    }
+
+    OatClassType GetType() const {
+      return type_;
+    }
 
     // get the OatMethod entry based on its index into the class
     // defintion. direct methods come first, followed by virtual
@@ -157,10 +164,21 @@ class OatFile {
    private:
     OatClass(const OatFile* oat_file,
              mirror::Class::Status status,
+             OatClassType type,
+             uint32_t bitmap_size,
+             const uint32_t* bitmap_pointer,
              const OatMethodOffsets* methods_pointer);
 
     const OatFile* oat_file_;
+
     const mirror::Class::Status status_;
+    COMPILE_ASSERT(mirror::Class::Status::kStatusMax < (2 ^ 16), class_status_wont_fit_in_16bits);
+
+    OatClassType type_;
+    COMPILE_ASSERT(OatClassType::kOatClassMax < (2 ^ 16), oat_class_type_wont_fit_in_16bits);
+
+    const BitVector* bitmap_;
+
     const OatMethodOffsets* methods_pointer_;
 
     friend class OatDexFile;