src/compiler.cc - platform/art - Git at Google

 // Copyright 2011 Google Inc. All Rights Reserved.

 #include "compiler.h"

 #include <sys/mman.h>

 #include "assembler.h"
 #include "class_linker.h"
 #include "class_loader.h"
 #include "dex_cache.h"
 #include "jni_compiler.h"
 #include "jni_internal.h"
 #include "runtime.h"

 extern bool oatCompileMethod(const art::Compiler& compiler, art::Method*, art::InstructionSet);

 namespace art {

 namespace arm {
   ByteArray* CreateAbstractMethodErrorStub();
 }

 namespace x86 {
   ByteArray* CreateAbstractMethodErrorStub();
 }

 Compiler::Compiler(InstructionSet insns) : instruction_set_(insns), jni_compiler_(insns),
     verbose_(false) {
   CHECK(!Runtime::Current()->IsStarted());
   if (insns == kArm || insns == kThumb2) {
     abstract_method_error_stub_ = arm::CreateAbstractMethodErrorStub();
   } else if (insns == kX86) {
     abstract_method_error_stub_ = x86::CreateAbstractMethodErrorStub();
   }
 }

 void Compiler::CompileAll(const ClassLoader* class_loader) {
   DCHECK(!Runtime::Current()->IsStarted());
   Resolve(class_loader);
   Verify(class_loader);
   InitializeClassesWithoutClinit(class_loader);
   Compile(class_loader);
   SetCodeAndDirectMethods(class_loader);
 }

 void Compiler::CompileOne(Method* method) {
   DCHECK(!Runtime::Current()->IsStarted());
   const ClassLoader* class_loader = method->GetDeclaringClass()->GetClassLoader();
   Resolve(class_loader);
   Verify(class_loader);
   InitializeClassesWithoutClinit(class_loader);
   CompileMethod(method);
   SetCodeAndDirectMethods(class_loader);
 }

 void Compiler::Resolve(const ClassLoader* class_loader) {
   const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
   for (size_t i = 0; i != class_path.size(); ++i) {
     const DexFile* dex_file = class_path[i];
     CHECK(dex_file != NULL);
     ResolveDexFile(class_loader, *dex_file);
   }
 }

 void Compiler::ResolveDexFile(const ClassLoader* class_loader, const DexFile& dex_file) {
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();

   // Strings are easy, they always are simply resolved to literals in the same file
   DexCache* dex_cache = class_linker->FindDexCache(dex_file);
   for (size_t string_idx = 0; string_idx < dex_cache->NumStrings(); string_idx++) {
     class_linker->ResolveString(dex_file, string_idx, dex_cache);
   }

   // Class derived values are more complicated, they require the linker and loader.
   for (size_t type_idx = 0; type_idx < dex_cache->NumResolvedTypes(); type_idx++) {
     Class* klass = class_linker->ResolveType(dex_file, type_idx, dex_cache, class_loader);
     if (klass == NULL) {
       Thread::Current()->ClearException();
     }
   }

   // Method and Field are the worst. We can't resolve without either
   // context from the code use (to disambiguate virtual vs direct
   // method and instance vs static field) or from class
   // definitions. While the compiler will resolve what it can as it
   // needs it, here we try to resolve fields and methods used in class
   // definitions, since many of them many never be referenced by
   // generated code.
   for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
     const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);

     // Note the class_data pointer advances through the headers,
     // static fields, instance fields, direct methods, and virtual
     // methods.
     const byte* class_data = dex_file.GetClassData(class_def);

     DexFile::ClassDataHeader header = dex_file.ReadClassDataHeader(&class_data);
     size_t num_static_fields = header.static_fields_size_;
     size_t num_instance_fields = header.instance_fields_size_;
     size_t num_direct_methods = header.direct_methods_size_;
     size_t num_virtual_methods = header.virtual_methods_size_;

     if (num_static_fields != 0) {
       uint32_t last_idx = 0;
       for (size_t i = 0; i < num_static_fields; ++i) {
         DexFile::Field dex_field;
         dex_file.dexReadClassDataField(&class_data, &dex_field, &last_idx);
         Field* field = class_linker->ResolveField(dex_file, dex_field.field_idx_, dex_cache,
                                                   class_loader, true);
         if (field == NULL) {
           Thread* self = Thread::Current();
           CHECK(self->IsExceptionPending());
           self->ClearException();
         }
       }
     }
     if (num_instance_fields != 0) {
       uint32_t last_idx = 0;
       for (size_t i = 0; i < num_instance_fields; ++i) {
         DexFile::Field dex_field;
         dex_file.dexReadClassDataField(&class_data, &dex_field, &last_idx);
         Field* field = class_linker->ResolveField(dex_file, dex_field.field_idx_, dex_cache,
                                                   class_loader, false);
         if (field == NULL) {
           Thread* self = Thread::Current();
           CHECK(self->IsExceptionPending());
           self->ClearException();
         }
       }
     }
     if (num_direct_methods != 0) {
       uint32_t last_idx = 0;
       for (size_t i = 0; i < num_direct_methods; ++i) {
         DexFile::Method dex_method;
         dex_file.dexReadClassDataMethod(&class_data, &dex_method, &last_idx);
         Method* method = class_linker->ResolveMethod(dex_file, dex_method.method_idx_, dex_cache,
                                                      class_loader, true);
         if (method == NULL) {
           Thread* self = Thread::Current();
           CHECK(self->IsExceptionPending());
           self->ClearException();
         }
       }
     }
     if (num_virtual_methods != 0) {
       uint32_t last_idx = 0;
       for (size_t i = 0; i < num_virtual_methods; ++i) {
         DexFile::Method dex_method;
         dex_file.dexReadClassDataMethod(&class_data, &dex_method, &last_idx);
         Method* method = class_linker->ResolveMethod(dex_file, dex_method.method_idx_, dex_cache,
                                                      class_loader, false);
         if (method == NULL) {
           Thread* self = Thread::Current();
           CHECK(self->IsExceptionPending());
           self->ClearException();
         }
       }
     }
   }
 }

 void Compiler::Verify(const ClassLoader* class_loader) {
   const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
   for (size_t i = 0; i != class_path.size(); ++i) {
     const DexFile* dex_file = class_path[i];
     CHECK(dex_file != NULL);
     VerifyDexFile(class_loader, *dex_file);
   }
 }

 void Compiler::VerifyDexFile(const ClassLoader* class_loader, const DexFile& dex_file) {
   dex_file.ChangePermissions(PROT_READ | PROT_WRITE);
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
   for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
     const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
     const char* descriptor = dex_file.GetClassDescriptor(class_def);
     Class* klass = class_linker->FindClass(descriptor, class_loader);
     if (klass == NULL) {
       Thread* self = Thread::Current();
       CHECK(self->IsExceptionPending());
       self->ClearException();
       continue;
     }
     CHECK(klass->IsResolved()) << PrettyClass(klass);
     class_linker->VerifyClass(klass);
     CHECK(klass->IsVerified() || klass->IsErroneous()) << PrettyClass(klass);
     //CHECK(!Thread::Current()->IsExceptionPending());
     if (klass->IsErroneous()) {
       Thread* self = Thread::Current();
       if (self->IsExceptionPending()) {
         UNIMPLEMENTED(WARNING) << "Verifier failed to cleanup exceptions internally";
         self->ClearException();
       }
     }
   }
   dex_file.ChangePermissions(PROT_READ);
 }

 void Compiler::InitializeClassesWithoutClinit(const ClassLoader* class_loader) {
   const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
   for (size_t i = 0; i != class_path.size(); ++i) {
     const DexFile* dex_file = class_path[i];
     CHECK(dex_file != NULL);
     InitializeClassesWithoutClinit(class_loader, *dex_file);
   }
 }

 void Compiler::InitializeClassesWithoutClinit(const ClassLoader* class_loader, const DexFile& dex_file) {
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
   for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
     const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
     const char* descriptor = dex_file.GetClassDescriptor(class_def);
     Class* klass = class_linker->FindClass(descriptor, class_loader);
     if (klass != NULL) {
       class_linker->EnsureInitialized(klass, false);
     }
     // clear any class not found or verification exceptions
     Thread::Current()->ClearException();
   }

   DexCache* dex_cache = class_linker->FindDexCache(dex_file);
   for (size_t type_idx = 0; type_idx < dex_cache->NumResolvedTypes(); type_idx++) {
     Class* klass = class_linker->ResolveType(dex_file, type_idx, dex_cache, class_loader);
     if (klass == NULL) {
       Thread::Current()->ClearException();
     } else if (klass->IsInitialized()) {
       dex_cache->GetInitializedStaticStorage()->Set(type_idx, klass);
     }
   }
 }

 void Compiler::Compile(const ClassLoader* class_loader) {
   const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
   for (size_t i = 0; i != class_path.size(); ++i) {
     const DexFile* dex_file = class_path[i];
     CHECK(dex_file != NULL);
     CompileDexFile(class_loader, *dex_file);
   }
 }

 void Compiler::CompileDexFile(const ClassLoader* class_loader, const DexFile& dex_file) {
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
   for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
     const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
     const char* descriptor = dex_file.GetClassDescriptor(class_def);
     Class* klass = class_linker->FindClass(descriptor, class_loader);
     if (klass == NULL) {
       // previous verification error will cause FindClass to throw
       Thread* self = Thread::Current();
       CHECK(self->IsExceptionPending());
       self->ClearException();
     } else {
       CompileClass(klass);
     }
   }
 }

 void Compiler::CompileClass(Class* klass) {
   for (size_t i = 0; i < klass->NumDirectMethods(); i++) {
     CompileMethod(klass->GetDirectMethod(i));
   }
   for (size_t i = 0; i < klass->NumVirtualMethods(); i++) {
     CompileMethod(klass->GetVirtualMethod(i));
   }
 }

 namespace arm {
   void ArmCreateInvokeStub(Method* method);
 }
 namespace x86 {
   void X86CreateInvokeStub(Method* method);
 }

 void Compiler::CompileMethod(Method* method) {
   if (method->IsNative()) {
     jni_compiler_.Compile(method);
     // unregister will install the stub to lookup via dlsym
     // TODO: this is only necessary for tests
     if (!method->IsRegistered()) {
       method->UnregisterNative();
     }
   } else if (method->IsAbstract()) {
     DCHECK(abstract_method_error_stub_ != NULL);
     if (instruction_set_ == kX86) {
       method->SetCode(abstract_method_error_stub_, kX86);
     } else {
       CHECK(instruction_set_ == kArm || instruction_set_ == kThumb2);
       method->SetCode(abstract_method_error_stub_, kArm);
     }
   } else {
     oatCompileMethod(*this, method, kThumb2);
   }
   CHECK(method->GetCode() != NULL);

   if (instruction_set_ == kX86) {
     art::x86::X86CreateInvokeStub(method);
   } else {
     CHECK(instruction_set_ == kArm || instruction_set_ == kThumb2);
     // Generates invocation stub using ARM instruction set
     art::arm::ArmCreateInvokeStub(method);
   }
   CHECK(method->GetInvokeStub() != NULL);
 }

 void Compiler::SetCodeAndDirectMethods(const ClassLoader* class_loader) {
   const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
   for (size_t i = 0; i != class_path.size(); ++i) {
     const DexFile* dex_file = class_path[i];
     CHECK(dex_file != NULL);
     SetCodeAndDirectMethodsDexFile(*dex_file);
   }
 }

 void Compiler::SetCodeAndDirectMethodsDexFile(const DexFile& dex_file) {
   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
   DexCache* dex_cache = class_linker->FindDexCache(dex_file);
   CodeAndDirectMethods* code_and_direct_methods = dex_cache->GetCodeAndDirectMethods();
   for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) {
     Method* method = dex_cache->GetResolvedMethod(i);
     if (method == NULL) {
       code_and_direct_methods->SetResolvedDirectMethodTrampoline(i);
     } else if (method->IsDirect()) {
       code_and_direct_methods->SetResolvedDirectMethod(i, method);
     } else {
       // TODO: we currently leave the entry blank for resolved
       // non-direct methods.  we could put in an error stub.
     }
   }
 }

 }  // namespace art
	// Copyright 2011 Google Inc. All Rights Reserved.

	#include "compiler.h"

	#include <sys/mman.h>

	#include "assembler.h"
	#include "class_linker.h"
	#include "class_loader.h"
	#include "dex_cache.h"
	#include "jni_compiler.h"
	#include "jni_internal.h"
	#include "runtime.h"

	extern bool oatCompileMethod(const art::Compiler& compiler, art::Method*, art::InstructionSet);

	namespace art {

	namespace arm {
	ByteArray* CreateAbstractMethodErrorStub();
	}

	namespace x86 {
	ByteArray* CreateAbstractMethodErrorStub();
	}

	Compiler::Compiler(InstructionSet insns) : instruction_set_(insns), jni_compiler_(insns),
	verbose_(false) {
	CHECK(!Runtime::Current()->IsStarted());
	if (insns == kArm \|\| insns == kThumb2) {
	abstract_method_error_stub_ = arm::CreateAbstractMethodErrorStub();
	} else if (insns == kX86) {
	abstract_method_error_stub_ = x86::CreateAbstractMethodErrorStub();
	}
	}

	void Compiler::CompileAll(const ClassLoader* class_loader) {
	DCHECK(!Runtime::Current()->IsStarted());
	Resolve(class_loader);
	Verify(class_loader);
	InitializeClassesWithoutClinit(class_loader);
	Compile(class_loader);
	SetCodeAndDirectMethods(class_loader);
	}

	void Compiler::CompileOne(Method* method) {
	DCHECK(!Runtime::Current()->IsStarted());
	const ClassLoader* class_loader = method->GetDeclaringClass()->GetClassLoader();
	Resolve(class_loader);
	Verify(class_loader);
	InitializeClassesWithoutClinit(class_loader);
	CompileMethod(method);
	SetCodeAndDirectMethods(class_loader);
	}

	void Compiler::Resolve(const ClassLoader* class_loader) {
	const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
	for (size_t i = 0; i != class_path.size(); ++i) {
	const DexFile* dex_file = class_path[i];
	CHECK(dex_file != NULL);
	ResolveDexFile(class_loader, *dex_file);
	}
	}

	void Compiler::ResolveDexFile(const ClassLoader* class_loader, const DexFile& dex_file) {
	ClassLinker* class_linker = Runtime::Current()->GetClassLinker();

	// Strings are easy, they always are simply resolved to literals in the same file
	DexCache* dex_cache = class_linker->FindDexCache(dex_file);
	for (size_t string_idx = 0; string_idx < dex_cache->NumStrings(); string_idx++) {
	class_linker->ResolveString(dex_file, string_idx, dex_cache);
	}

	// Class derived values are more complicated, they require the linker and loader.
	for (size_t type_idx = 0; type_idx < dex_cache->NumResolvedTypes(); type_idx++) {
	Class* klass = class_linker->ResolveType(dex_file, type_idx, dex_cache, class_loader);
	if (klass == NULL) {
	Thread::Current()->ClearException();
	}
	}

	// Method and Field are the worst. We can't resolve without either
	// context from the code use (to disambiguate virtual vs direct
	// method and instance vs static field) or from class
	// definitions. While the compiler will resolve what it can as it
	// needs it, here we try to resolve fields and methods used in class
	// definitions, since many of them many never be referenced by
	// generated code.
	for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
	const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);

	// Note the class_data pointer advances through the headers,
	// static fields, instance fields, direct methods, and virtual
	// methods.
	const byte* class_data = dex_file.GetClassData(class_def);

	DexFile::ClassDataHeader header = dex_file.ReadClassDataHeader(&class_data);
	size_t num_static_fields = header.static_fields_size_;
	size_t num_instance_fields = header.instance_fields_size_;
	size_t num_direct_methods = header.direct_methods_size_;
	size_t num_virtual_methods = header.virtual_methods_size_;

	if (num_static_fields != 0) {
	uint32_t last_idx = 0;
	for (size_t i = 0; i < num_static_fields; ++i) {
	DexFile::Field dex_field;
	dex_file.dexReadClassDataField(&class_data, &dex_field, &last_idx);
	Field* field = class_linker->ResolveField(dex_file, dex_field.field_idx_, dex_cache,
	class_loader, true);
	if (field == NULL) {
	Thread* self = Thread::Current();
	CHECK(self->IsExceptionPending());
	self->ClearException();
	}
	}
	}
	if (num_instance_fields != 0) {
	uint32_t last_idx = 0;
	for (size_t i = 0; i < num_instance_fields; ++i) {
	DexFile::Field dex_field;
	dex_file.dexReadClassDataField(&class_data, &dex_field, &last_idx);
	Field* field = class_linker->ResolveField(dex_file, dex_field.field_idx_, dex_cache,
	class_loader, false);
	if (field == NULL) {
	Thread* self = Thread::Current();
	CHECK(self->IsExceptionPending());
	self->ClearException();
	}
	}
	}
	if (num_direct_methods != 0) {
	uint32_t last_idx = 0;
	for (size_t i = 0; i < num_direct_methods; ++i) {
	DexFile::Method dex_method;
	dex_file.dexReadClassDataMethod(&class_data, &dex_method, &last_idx);
	Method* method = class_linker->ResolveMethod(dex_file, dex_method.method_idx_, dex_cache,
	class_loader, true);
	if (method == NULL) {
	Thread* self = Thread::Current();
	CHECK(self->IsExceptionPending());
	self->ClearException();
	}
	}
	}
	if (num_virtual_methods != 0) {
	uint32_t last_idx = 0;
	for (size_t i = 0; i < num_virtual_methods; ++i) {
	DexFile::Method dex_method;
	dex_file.dexReadClassDataMethod(&class_data, &dex_method, &last_idx);
	Method* method = class_linker->ResolveMethod(dex_file, dex_method.method_idx_, dex_cache,
	class_loader, false);
	if (method == NULL) {
	Thread* self = Thread::Current();
	CHECK(self->IsExceptionPending());
	self->ClearException();
	}
	}
	}
	}
	}

	void Compiler::Verify(const ClassLoader* class_loader) {
	const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
	for (size_t i = 0; i != class_path.size(); ++i) {
	const DexFile* dex_file = class_path[i];
	CHECK(dex_file != NULL);
	VerifyDexFile(class_loader, *dex_file);
	}
	}

	void Compiler::VerifyDexFile(const ClassLoader* class_loader, const DexFile& dex_file) {
	dex_file.ChangePermissions(PROT_READ \| PROT_WRITE);
	ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
	for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
	const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
	const char* descriptor = dex_file.GetClassDescriptor(class_def);
	Class* klass = class_linker->FindClass(descriptor, class_loader);
	if (klass == NULL) {
	Thread* self = Thread::Current();
	CHECK(self->IsExceptionPending());
	self->ClearException();
	continue;
	}
	CHECK(klass->IsResolved()) << PrettyClass(klass);
	class_linker->VerifyClass(klass);
	CHECK(klass->IsVerified() \|\| klass->IsErroneous()) << PrettyClass(klass);
	//CHECK(!Thread::Current()->IsExceptionPending());
	if (klass->IsErroneous()) {
	Thread* self = Thread::Current();
	if (self->IsExceptionPending()) {
	UNIMPLEMENTED(WARNING) << "Verifier failed to cleanup exceptions internally";
	self->ClearException();
	}
	}
	}
	dex_file.ChangePermissions(PROT_READ);
	}

	void Compiler::InitializeClassesWithoutClinit(const ClassLoader* class_loader) {
	const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
	for (size_t i = 0; i != class_path.size(); ++i) {
	const DexFile* dex_file = class_path[i];
	CHECK(dex_file != NULL);
	InitializeClassesWithoutClinit(class_loader, *dex_file);
	}
	}

	void Compiler::InitializeClassesWithoutClinit(const ClassLoader* class_loader, const DexFile& dex_file) {
	ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
	for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
	const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
	const char* descriptor = dex_file.GetClassDescriptor(class_def);
	Class* klass = class_linker->FindClass(descriptor, class_loader);
	if (klass != NULL) {
	class_linker->EnsureInitialized(klass, false);
	}
	// clear any class not found or verification exceptions
	Thread::Current()->ClearException();
	}

	DexCache* dex_cache = class_linker->FindDexCache(dex_file);
	for (size_t type_idx = 0; type_idx < dex_cache->NumResolvedTypes(); type_idx++) {
	Class* klass = class_linker->ResolveType(dex_file, type_idx, dex_cache, class_loader);
	if (klass == NULL) {
	Thread::Current()->ClearException();
	} else if (klass->IsInitialized()) {
	dex_cache->GetInitializedStaticStorage()->Set(type_idx, klass);
	}
	}
	}

	void Compiler::Compile(const ClassLoader* class_loader) {
	const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
	for (size_t i = 0; i != class_path.size(); ++i) {
	const DexFile* dex_file = class_path[i];
	CHECK(dex_file != NULL);
	CompileDexFile(class_loader, *dex_file);
	}
	}

	void Compiler::CompileDexFile(const ClassLoader* class_loader, const DexFile& dex_file) {
	ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
	for (size_t class_def_index = 0; class_def_index < dex_file.NumClassDefs(); class_def_index++) {
	const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
	const char* descriptor = dex_file.GetClassDescriptor(class_def);
	Class* klass = class_linker->FindClass(descriptor, class_loader);
	if (klass == NULL) {
	// previous verification error will cause FindClass to throw
	Thread* self = Thread::Current();
	CHECK(self->IsExceptionPending());
	self->ClearException();
	} else {
	CompileClass(klass);
	}
	}
	}

	void Compiler::CompileClass(Class* klass) {
	for (size_t i = 0; i < klass->NumDirectMethods(); i++) {
	CompileMethod(klass->GetDirectMethod(i));
	}
	for (size_t i = 0; i < klass->NumVirtualMethods(); i++) {
	CompileMethod(klass->GetVirtualMethod(i));
	}
	}

	namespace arm {
	void ArmCreateInvokeStub(Method* method);
	}
	namespace x86 {
	void X86CreateInvokeStub(Method* method);
	}

	void Compiler::CompileMethod(Method* method) {
	if (method->IsNative()) {
	jni_compiler_.Compile(method);
	// unregister will install the stub to lookup via dlsym
	// TODO: this is only necessary for tests
	if (!method->IsRegistered()) {
	method->UnregisterNative();
	}
	} else if (method->IsAbstract()) {
	DCHECK(abstract_method_error_stub_ != NULL);
	if (instruction_set_ == kX86) {
	method->SetCode(abstract_method_error_stub_, kX86);
	} else {
	CHECK(instruction_set_ == kArm \|\| instruction_set_ == kThumb2);
	method->SetCode(abstract_method_error_stub_, kArm);
	}
	} else {
	oatCompileMethod(*this, method, kThumb2);
	}
	CHECK(method->GetCode() != NULL);

	if (instruction_set_ == kX86) {
	art::x86::X86CreateInvokeStub(method);
	} else {
	CHECK(instruction_set_ == kArm \|\| instruction_set_ == kThumb2);
	// Generates invocation stub using ARM instruction set
	art::arm::ArmCreateInvokeStub(method);
	}
	CHECK(method->GetInvokeStub() != NULL);
	}

	void Compiler::SetCodeAndDirectMethods(const ClassLoader* class_loader) {
	const std::vector<const DexFile*>& class_path = ClassLoader::GetClassPath(class_loader);
	for (size_t i = 0; i != class_path.size(); ++i) {
	const DexFile* dex_file = class_path[i];
	CHECK(dex_file != NULL);
	SetCodeAndDirectMethodsDexFile(*dex_file);
	}
	}

	void Compiler::SetCodeAndDirectMethodsDexFile(const DexFile& dex_file) {
	ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
	DexCache* dex_cache = class_linker->FindDexCache(dex_file);
	CodeAndDirectMethods* code_and_direct_methods = dex_cache->GetCodeAndDirectMethods();
	for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) {
	Method* method = dex_cache->GetResolvedMethod(i);
	if (method == NULL) {
	code_and_direct_methods->SetResolvedDirectMethodTrampoline(i);
	} else if (method->IsDirect()) {
	code_and_direct_methods->SetResolvedDirectMethod(i, method);
	} else {
	// TODO: we currently leave the entry blank for resolved
	// non-direct methods. we could put in an error stub.
	}
	}
	}

	} // namespace art