Use direct class pointers at allocation sites in the compiled code.

- Rather than looking up a class from its type ID (and checking if
  it's resolved/initialized, resolving/initializing if not), use
  direct class pointers, if possible (boot-code-to-boot-class pointers
  and app-code-to-boot-class pointers.)
- This results in a 1-2% speedup in Ritz MemAllocTest on Nexus 4.
- Embedding the object size (along with class pointers) caused a 1-2%
  slowdown in MemAllocTest and isn't implemented in this change.
- TODO: do the same for array allocations.
- TODO: when/if an application gets its own image, implement
  app-code-to-app-class pointers.
- Fix a -XX:gc bug.
  cf. https://android-review.googlesource.com/79460/
- Add /tmp/android-data/dalvik-cache to the list of locations to
  remove oat files in clean-oat-host.
  cf. https://android-review.googlesource.com/79550
- Add back a dropped UNLIKELY in FindMethodFromCode().
  cf. https://android-review.googlesource.com/74205

Bug: 9986565
Change-Id: I590b96bd21f7a7472f88e36752e675547559a5b1
diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index f713151..f390b41 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -439,6 +439,10 @@
     MutexLock mu(self, compiled_methods_lock_);
     STLDeleteElements(&methods_to_patch_);
   }
+  {
+    MutexLock mu(self, compiled_methods_lock_);
+    STLDeleteElements(&classes_to_patch_);
+  }
   CHECK_PTHREAD_CALL(pthread_key_delete, (tls_key_), "delete tls key");
   typedef void (*UninitCompilerContextFn)(CompilerDriver&);
   UninitCompilerContextFn uninit_compiler_context;
@@ -906,6 +910,51 @@
   return result;
 }
 
+bool CompilerDriver::CanEmbedTypeInCode(const DexFile& dex_file, uint32_t type_idx,
+                                        bool* is_type_initialized, bool* use_direct_type_ptr,
+                                        uintptr_t* direct_type_ptr) {
+  ScopedObjectAccess soa(Thread::Current());
+  mirror::DexCache* dex_cache = Runtime::Current()->GetClassLinker()->FindDexCache(dex_file);
+  mirror::Class* resolved_class = dex_cache->GetResolvedType(type_idx);
+  if (resolved_class == nullptr) {
+    return false;
+  }
+  const bool compiling_boot = Runtime::Current()->GetHeap()->IsCompilingBoot();
+  if (compiling_boot) {
+    // boot -> boot class pointers.
+    // True if the class is in the image at boot compiling time.
+    const bool is_image_class = IsImage() && IsImageClass(
+        dex_file.StringDataByIdx(dex_file.GetTypeId(type_idx).descriptor_idx_));
+    // True if pc relative load works.
+    const bool support_boot_image_fixup = GetSupportBootImageFixup();
+    if (is_image_class && support_boot_image_fixup) {
+      *is_type_initialized = resolved_class->IsInitialized();
+      *use_direct_type_ptr = false;
+      *direct_type_ptr = 0;
+      return true;
+    } else {
+      return false;
+    }
+  } else {
+    // True if the class is in the image at app compiling time.
+    const bool class_in_image =
+        Runtime::Current()->GetHeap()->FindSpaceFromObject(resolved_class, false)->IsImageSpace();
+    if (class_in_image) {
+      // boot -> app class pointers.
+      *is_type_initialized = resolved_class->IsInitialized();
+      *use_direct_type_ptr = true;
+      *direct_type_ptr = reinterpret_cast<uintptr_t>(resolved_class);
+      return true;
+    } else {
+      // app -> app class pointers.
+      // Give up because app does not have an image and class
+      // isn't created at compile time.  TODO: implement this
+      // if/when each app gets an image.
+      return false;
+    }
+  }
+}
+
 static mirror::Class* ComputeCompilingMethodsClass(ScopedObjectAccess& soa,
                                                    SirtRef<mirror::DexCache>& dex_cache,
                                                    const DexCompilationUnit* mUnit)
@@ -1291,13 +1340,13 @@
                                   InvokeType target_invoke_type,
                                   size_t literal_offset) {
   MutexLock mu(Thread::Current(), compiled_methods_lock_);
-  code_to_patch_.push_back(new PatchInformation(dex_file,
-                                                referrer_class_def_idx,
-                                                referrer_method_idx,
-                                                referrer_invoke_type,
-                                                target_method_idx,
-                                                target_invoke_type,
-                                                literal_offset));
+  code_to_patch_.push_back(new CallPatchInformation(dex_file,
+                                                    referrer_class_def_idx,
+                                                    referrer_method_idx,
+                                                    referrer_invoke_type,
+                                                    target_method_idx,
+                                                    target_invoke_type,
+                                                    literal_offset));
 }
 void CompilerDriver::AddMethodPatch(const DexFile* dex_file,
                                     uint16_t referrer_class_def_idx,
@@ -1307,13 +1356,25 @@
                                     InvokeType target_invoke_type,
                                     size_t literal_offset) {
   MutexLock mu(Thread::Current(), compiled_methods_lock_);
-  methods_to_patch_.push_back(new PatchInformation(dex_file,
-                                                   referrer_class_def_idx,
-                                                   referrer_method_idx,
-                                                   referrer_invoke_type,
-                                                   target_method_idx,
-                                                   target_invoke_type,
-                                                   literal_offset));
+  methods_to_patch_.push_back(new CallPatchInformation(dex_file,
+                                                       referrer_class_def_idx,
+                                                       referrer_method_idx,
+                                                       referrer_invoke_type,
+                                                       target_method_idx,
+                                                       target_invoke_type,
+                                                       literal_offset));
+}
+void CompilerDriver::AddClassPatch(const DexFile* dex_file,
+                                    uint16_t referrer_class_def_idx,
+                                    uint32_t referrer_method_idx,
+                                    uint32_t target_type_idx,
+                                    size_t literal_offset) {
+  MutexLock mu(Thread::Current(), compiled_methods_lock_);
+  classes_to_patch_.push_back(new TypePatchInformation(dex_file,
+                                                       referrer_class_def_idx,
+                                                       referrer_method_idx,
+                                                       target_type_idx,
+                                                       literal_offset));
 }
 
 class ParallelCompilationManager {