Record profiling information before Jitting.

- Add a new instrumentation kind to record dynamic invokes.
- Use the JNI entry point field to store the profiling data.
- Record seen receivers for every dynamic invoke.

Change-Id: I2c1738ab2a72052d45964d055dc16b44b906e54c
diff --git a/runtime/jit/profiling_info.cc b/runtime/jit/profiling_info.cc
new file mode 100644
index 0000000..0c039f2
--- /dev/null
+++ b/runtime/jit/profiling_info.cc
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2015 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 "profiling_info.h"
+
+#include "art_method-inl.h"
+#include "dex_instruction.h"
+#include "jit/jit.h"
+#include "jit/jit_code_cache.h"
+#include "scoped_thread_state_change.h"
+#include "thread.h"
+
+namespace art {
+
+ProfilingInfo* ProfilingInfo::Create(ArtMethod* method) {
+  // Walk over the dex instructions of the method and keep track of
+  // instructions we are interested in profiling.
+  const uint16_t* code_ptr = nullptr;
+  const uint16_t* code_end = nullptr;
+  {
+    ScopedObjectAccess soa(Thread::Current());
+    DCHECK(!method->IsNative());
+    const DexFile::CodeItem& code_item = *method->GetCodeItem();
+    code_ptr = code_item.insns_;
+    code_end = code_item.insns_ + code_item.insns_size_in_code_units_;
+  }
+
+  uint32_t dex_pc = 0;
+  std::vector<uint32_t> entries;
+  while (code_ptr < code_end) {
+    const Instruction& instruction = *Instruction::At(code_ptr);
+    switch (instruction.Opcode()) {
+      case Instruction::INVOKE_VIRTUAL:
+      case Instruction::INVOKE_VIRTUAL_RANGE:
+      case Instruction::INVOKE_VIRTUAL_QUICK:
+      case Instruction::INVOKE_VIRTUAL_RANGE_QUICK:
+      case Instruction::INVOKE_INTERFACE:
+      case Instruction::INVOKE_INTERFACE_RANGE:
+        entries.push_back(dex_pc);
+        break;
+
+      default:
+        break;
+    }
+    dex_pc += instruction.SizeInCodeUnits();
+    code_ptr += instruction.SizeInCodeUnits();
+  }
+
+  // If there is no instruction we are interested in, no need to create a `ProfilingInfo`
+  // object, it will never be filled.
+  if (entries.empty()) {
+    return nullptr;
+  }
+
+  // Allocate the `ProfilingInfo` object int the JIT's data space.
+  jit::JitCodeCache* code_cache = Runtime::Current()->GetJit()->GetCodeCache();
+  size_t profile_info_size = sizeof(ProfilingInfo) + sizeof(InlineCache) * entries.size();
+  uint8_t* data = code_cache->ReserveData(Thread::Current(), profile_info_size);
+
+  if (data == nullptr) {
+    VLOG(jit) << "Cannot allocate profiling info anymore";
+    return nullptr;
+  }
+
+  return new (data) ProfilingInfo(entries);
+}
+
+void ProfilingInfo::AddInvokeInfo(Thread* self, uint32_t dex_pc, mirror::Class* cls) {
+  InlineCache* cache = nullptr;
+  // TODO: binary search if array is too long.
+  for (size_t i = 0; i < number_of_inline_caches_; ++i) {
+    if (cache_[i].dex_pc == dex_pc) {
+      cache = &cache_[i];
+      break;
+    }
+  }
+  DCHECK(cache != nullptr);
+
+  ScopedObjectAccess soa(self);
+  for (size_t i = 0; i < InlineCache::kIndividualCacheSize; ++i) {
+    mirror::Class* existing = cache->classes_[i].Read<kWithoutReadBarrier>();
+    if (existing == cls) {
+      // Receiver type is already in the cache, nothing else to do.
+      return;
+    } else if (existing == nullptr) {
+      // Cache entry is empty, try to put `cls` in it.
+      GcRoot<mirror::Class> expected_root(nullptr);
+      GcRoot<mirror::Class> desired_root(cls);
+      if (!reinterpret_cast<Atomic<GcRoot<mirror::Class>>*>(&cache->classes_[i])->
+              CompareExchangeStrongSequentiallyConsistent(expected_root, desired_root)) {
+        // Some other thread put a class in the cache, continue iteration starting at this
+        // entry in case the entry contains `cls`.
+        --i;
+      } else {
+        // We successfully set `cls`, just return.
+        return;
+      }
+    }
+  }
+  // Unsuccessfull - cache is full, making it megamorphic.
+  DCHECK(cache->IsMegamorphic());
+}
+
+}  // namespace art