/* * 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 #include #include "assembler.h" #include "calling_convention.h" #include "class_linker.h" #include "compiled_method.h" #include "compiler.h" #include "constants.h" #include "jni_internal.h" #include "logging.h" #include "macros.h" #include "managed_register.h" #include "thread.h" #include "UniquePtr.h" #define __ jni_asm-> namespace art { static void ChangeThreadState(Assembler* jni_asm, Thread::State new_state, ManagedRegister scratch, ManagedRegister return_reg, FrameOffset return_save_location, size_t return_size) { /* * This code mirrors that of Thread::SetState where detail is given on why * barriers occur when they do. */ if (new_state == Thread::kRunnable) { /* * Change our status to Thread::kRunnable. The transition requires * that we check for pending suspension, because the VM considers * us to be "asleep" in all other states, and another thread could * be performing a GC now. */ __ StoreImmediateToThread(Thread::StateOffset(), Thread::kRunnable, scratch); __ MemoryBarrier(scratch); __ SuspendPoll(scratch, return_reg, return_save_location, return_size); } else { /* * Not changing to Thread::kRunnable. No additional work required. */ __ MemoryBarrier(scratch); __ StoreImmediateToThread(Thread::StateOffset(), new_state, scratch); } } // Copy a single parameter from the managed to the JNI calling convention static void CopyParameter(Assembler* jni_asm, ManagedRuntimeCallingConvention* mr_conv, JniCallingConvention* jni_conv, size_t frame_size, size_t out_arg_size) { bool input_in_reg = mr_conv->IsCurrentParamInRegister(); bool output_in_reg = jni_conv->IsCurrentParamInRegister(); FrameOffset sirt_offset(0); bool null_allowed = false; bool ref_param = jni_conv->IsCurrentParamAReference(); CHECK(!ref_param || mr_conv->IsCurrentParamAReference()); // input may be in register, on stack or both - but not none! CHECK(input_in_reg || mr_conv->IsCurrentParamOnStack()); if (output_in_reg) { // output shouldn't straddle registers and stack CHECK(!jni_conv->IsCurrentParamOnStack()); } else { CHECK(jni_conv->IsCurrentParamOnStack()); } // References need placing in SIRT and the entry address passing if (ref_param) { null_allowed = mr_conv->IsCurrentArgPossiblyNull(); // Compute SIRT offset. Note null is placed in the SIRT but the jobject // passed to the native code must be null (not a pointer into the SIRT // as with regular references). sirt_offset = jni_conv->CurrentParamSirtEntryOffset(); // Check SIRT offset is within frame. CHECK_LT(sirt_offset.Uint32Value(), (frame_size + out_arg_size)); } if (input_in_reg && output_in_reg) { ManagedRegister in_reg = mr_conv->CurrentParamRegister(); ManagedRegister out_reg = jni_conv->CurrentParamRegister(); if (ref_param) { __ CreateSirtEntry(out_reg, sirt_offset, in_reg, null_allowed); } else { if (!mr_conv->IsCurrentParamOnStack()) { // regular non-straddling move __ Move(out_reg, in_reg, mr_conv->CurrentParamSize()); } else { UNIMPLEMENTED(FATAL); // we currently don't expect to see this case } } } else if (!input_in_reg && !output_in_reg) { FrameOffset out_off = jni_conv->CurrentParamStackOffset(); if (ref_param) { __ CreateSirtEntry(out_off, sirt_offset, mr_conv->InterproceduralScratchRegister(), null_allowed); } else { FrameOffset in_off = mr_conv->CurrentParamStackOffset(); size_t param_size = mr_conv->CurrentParamSize(); CHECK_EQ(param_size, jni_conv->CurrentParamSize()); __ Copy(out_off, in_off, mr_conv->InterproceduralScratchRegister(), param_size); } } else if (!input_in_reg && output_in_reg) { FrameOffset in_off = mr_conv->CurrentParamStackOffset(); ManagedRegister out_reg = jni_conv->CurrentParamRegister(); // Check that incoming stack arguments are above the current stack frame. CHECK_GT(in_off.Uint32Value(), frame_size); if (ref_param) { __ CreateSirtEntry(out_reg, sirt_offset, ManagedRegister::NoRegister(), null_allowed); } else { size_t param_size = mr_conv->CurrentParamSize(); CHECK_EQ(param_size, jni_conv->CurrentParamSize()); __ Load(out_reg, in_off, param_size); } } else { CHECK(input_in_reg && !output_in_reg); ManagedRegister in_reg = mr_conv->CurrentParamRegister(); FrameOffset out_off = jni_conv->CurrentParamStackOffset(); // Check outgoing argument is within frame CHECK_LT(out_off.Uint32Value(), frame_size); if (ref_param) { // TODO: recycle value in in_reg rather than reload from SIRT __ CreateSirtEntry(out_off, sirt_offset, mr_conv->InterproceduralScratchRegister(), null_allowed); } else { size_t param_size = mr_conv->CurrentParamSize(); CHECK_EQ(param_size, jni_conv->CurrentParamSize()); if (!mr_conv->IsCurrentParamOnStack()) { // regular non-straddling store __ Store(out_off, in_reg, param_size); } else { // store where input straddles registers and stack CHECK_EQ(param_size, 8u); FrameOffset in_off = mr_conv->CurrentParamStackOffset(); __ StoreSpanning(out_off, in_reg, in_off, mr_conv->InterproceduralScratchRegister()); } } } } static void SetNativeParameter(Assembler* jni_asm, JniCallingConvention* jni_conv, ManagedRegister in_reg) { if (jni_conv->IsCurrentParamOnStack()) { FrameOffset dest = jni_conv->CurrentParamStackOffset(); __ StoreRawPtr(dest, in_reg); } else { if (!jni_conv->CurrentParamRegister().Equals(in_reg)) { __ Move(jni_conv->CurrentParamRegister(), in_reg, jni_conv->CurrentParamSize()); } } } // Generate the JNI bridge for the given method, general contract: // - Arguments are in the managed runtime format, either on stack or in // registers, a reference to the method object is supplied as part of this // convention. // CompiledMethod* ArtJniCompileMethodInternal(Compiler& compiler, uint32_t access_flags, uint32_t method_idx, const ClassLoader* class_loader, const DexFile& dex_file) { CHECK((access_flags & kAccNative) != 0); const bool is_static = (access_flags & kAccStatic) != 0; const bool is_synchronized = (access_flags & kAccSynchronized) != 0; const char* shorty = dex_file.GetMethodShorty(dex_file.GetMethodId(method_idx)); InstructionSet instruction_set = compiler.GetInstructionSet(); if (instruction_set == kThumb2) { instruction_set = kArm; } // Calling conventions used to iterate over parameters to method UniquePtr jni_conv( JniCallingConvention::Create(is_static, is_synchronized, shorty, instruction_set)); UniquePtr mr_conv( ManagedRuntimeCallingConvention::Create(is_static, is_synchronized, shorty, instruction_set)); // Assembler that holds generated instructions UniquePtr jni_asm(Assembler::Create(instruction_set)); // Offsets into data structures // TODO: if cross compiling these offsets are for the host not the target const Offset functions(OFFSETOF_MEMBER(JNIEnvExt, functions)); const Offset monitor_enter(OFFSETOF_MEMBER(JNINativeInterface, MonitorEnter)); const Offset monitor_exit(OFFSETOF_MEMBER(JNINativeInterface, MonitorExit)); // 1. Build the frame saving all callee saves const size_t frame_size(jni_conv->FrameSize()); const std::vector& callee_save_regs = jni_conv->CalleeSaveRegisters(); __ BuildFrame(frame_size, mr_conv->MethodRegister(), callee_save_regs, mr_conv->EntrySpills()); // 2. Set up the StackIndirectReferenceTable mr_conv->ResetIterator(FrameOffset(frame_size)); jni_conv->ResetIterator(FrameOffset(0)); __ StoreImmediateToFrame(jni_conv->SirtNumRefsOffset(), jni_conv->ReferenceCount(), mr_conv->InterproceduralScratchRegister()); __ CopyRawPtrFromThread(jni_conv->SirtLinkOffset(), Thread::TopSirtOffset(), mr_conv->InterproceduralScratchRegister()); __ StoreStackOffsetToThread(Thread::TopSirtOffset(), jni_conv->SirtOffset(), mr_conv->InterproceduralScratchRegister()); // 3. Place incoming reference arguments into SIRT jni_conv->Next(); // Skip JNIEnv* // 3.5. Create Class argument for static methods out of passed method if (is_static) { FrameOffset sirt_offset = jni_conv->CurrentParamSirtEntryOffset(); // Check sirt offset is within frame CHECK_LT(sirt_offset.Uint32Value(), frame_size); __ LoadRef(jni_conv->InterproceduralScratchRegister(), mr_conv->MethodRegister(), Method::DeclaringClassOffset()); __ VerifyObject(jni_conv->InterproceduralScratchRegister(), false); __ StoreRef(sirt_offset, jni_conv->InterproceduralScratchRegister()); jni_conv->Next(); // in SIRT so move to next argument } while (mr_conv->HasNext()) { CHECK(jni_conv->HasNext()); bool ref_param = jni_conv->IsCurrentParamAReference(); CHECK(!ref_param || mr_conv->IsCurrentParamAReference()); // References need placing in SIRT and the entry value passing if (ref_param) { // Compute SIRT entry, note null is placed in the SIRT but its boxed value // must be NULL FrameOffset sirt_offset = jni_conv->CurrentParamSirtEntryOffset(); // Check SIRT offset is within frame and doesn't run into the saved segment state CHECK_LT(sirt_offset.Uint32Value(), frame_size); CHECK_NE(sirt_offset.Uint32Value(), jni_conv->SavedLocalReferenceCookieOffset().Uint32Value()); bool input_in_reg = mr_conv->IsCurrentParamInRegister(); bool input_on_stack = mr_conv->IsCurrentParamOnStack(); CHECK(input_in_reg || input_on_stack); if (input_in_reg) { ManagedRegister in_reg = mr_conv->CurrentParamRegister(); __ VerifyObject(in_reg, mr_conv->IsCurrentArgPossiblyNull()); __ StoreRef(sirt_offset, in_reg); } else if (input_on_stack) { FrameOffset in_off = mr_conv->CurrentParamStackOffset(); __ VerifyObject(in_off, mr_conv->IsCurrentArgPossiblyNull()); __ CopyRef(sirt_offset, in_off, mr_conv->InterproceduralScratchRegister()); } } mr_conv->Next(); jni_conv->Next(); } // 4. Transition from being in managed to native code. Save the top_of_managed_stack_ // so that the managed stack can be crawled while in native code. Clear the corresponding // PC value that has no meaning for the this frame. __ StoreStackPointerToThread(Thread::TopOfManagedStackOffset()); __ StoreImmediateToThread(Thread::TopOfManagedStackPcOffset(), 0, mr_conv->InterproceduralScratchRegister()); ChangeThreadState(jni_asm.get(), Thread::kNative, mr_conv->InterproceduralScratchRegister(), ManagedRegister::NoRegister(), FrameOffset(0), 0); // 5. Move frame down to allow space for out going args. Do for as short a // time as possible to aid profiling.. const size_t out_arg_size = jni_conv->OutArgSize(); __ IncreaseFrameSize(out_arg_size); // 6. Acquire lock for synchronized methods. if (is_synchronized) { // Compute arguments in registers to preserve mr_conv->ResetIterator(FrameOffset(frame_size + out_arg_size)); std::vector live_argument_regs; std::vector live_argument_regs_size; while (mr_conv->HasNext()) { if (mr_conv->IsCurrentParamInRegister()) { live_argument_regs.push_back(mr_conv->CurrentParamRegister()); live_argument_regs_size.push_back(mr_conv->CurrentParamSize()); } mr_conv->Next(); } // Copy arguments to preserve to callee save registers CHECK_LE(live_argument_regs.size(), callee_save_regs.size()); for (size_t i = 0; i < live_argument_regs.size(); i++) { __ Move(callee_save_regs.at(i), live_argument_regs.at(i), live_argument_regs_size.at(i)); } // Get SIRT entry for 1st argument (jclass or this) to be 1st argument to // monitor enter mr_conv->ResetIterator(FrameOffset(frame_size + out_arg_size)); jni_conv->ResetIterator(FrameOffset(out_arg_size)); jni_conv->Next(); // Skip JNIEnv* if (is_static) { FrameOffset sirt_offset = jni_conv->CurrentParamSirtEntryOffset(); if (jni_conv->IsCurrentParamOnStack()) { FrameOffset out_off = jni_conv->CurrentParamStackOffset(); __ CreateSirtEntry(out_off, sirt_offset, mr_conv->InterproceduralScratchRegister(), false); } else { ManagedRegister out_reg = jni_conv->CurrentParamRegister(); __ CreateSirtEntry(out_reg, sirt_offset, ManagedRegister::NoRegister(), false); } } else { CopyParameter(jni_asm.get(), mr_conv.get(), jni_conv.get(), frame_size, out_arg_size); } // Generate JNIEnv* in place and leave a copy in jni_fns_register jni_conv->ResetIterator(FrameOffset(out_arg_size)); ManagedRegister jni_fns_register = jni_conv->InterproceduralScratchRegister(); __ LoadRawPtrFromThread(jni_fns_register, Thread::JniEnvOffset()); SetNativeParameter(jni_asm.get(), jni_conv.get(), jni_fns_register); // Call JNIEnv->MonitorEnter(object) __ LoadRawPtr(jni_fns_register, jni_fns_register, functions); __ Call(jni_fns_register, monitor_enter, jni_conv->InterproceduralScratchRegister()); // Check for exceptions __ ExceptionPoll(jni_conv->InterproceduralScratchRegister()); // Restore live arguments for (size_t i = 0; i < live_argument_regs.size(); i++) { __ Move(live_argument_regs.at(i), callee_save_regs.at(i), live_argument_regs_size.at(i)); } } // 7. Iterate over arguments placing values from managed calling convention in // to the convention required for a native call (shuffling). For references // place an index/pointer to the reference after checking whether it is // NULL (which must be encoded as NULL). // Note: we do this prior to materializing the JNIEnv* and static's jclass to // give as many free registers for the shuffle as possible mr_conv->ResetIterator(FrameOffset(frame_size+out_arg_size)); uint32_t args_count = 0; while (mr_conv->HasNext()) { args_count++; mr_conv->Next(); } // Do a backward pass over arguments, so that the generated code will be "mov // R2, R3; mov R1, R2" instead of "mov R1, R2; mov R2, R3." // TODO: A reverse iterator to improve readability. for (uint32_t i = 0; i < args_count; ++i) { mr_conv->ResetIterator(FrameOffset(frame_size + out_arg_size)); jni_conv->ResetIterator(FrameOffset(out_arg_size)); jni_conv->Next(); // Skip JNIEnv* if (is_static) { jni_conv->Next(); // Skip Class for now } for (uint32_t j = 0; j < args_count - i - 1; ++j) { mr_conv->Next(); jni_conv->Next(); } CopyParameter(jni_asm.get(), mr_conv.get(), jni_conv.get(), frame_size, out_arg_size); } if (is_static) { // Create argument for Class mr_conv->ResetIterator(FrameOffset(frame_size+out_arg_size)); jni_conv->ResetIterator(FrameOffset(out_arg_size)); jni_conv->Next(); // Skip JNIEnv* FrameOffset sirt_offset = jni_conv->CurrentParamSirtEntryOffset(); if (jni_conv->IsCurrentParamOnStack()) { FrameOffset out_off = jni_conv->CurrentParamStackOffset(); __ CreateSirtEntry(out_off, sirt_offset, mr_conv->InterproceduralScratchRegister(), false); } else { ManagedRegister out_reg = jni_conv->CurrentParamRegister(); __ CreateSirtEntry(out_reg, sirt_offset, ManagedRegister::NoRegister(), false); } } // 8. Create 1st argument, the JNI environment ptr and save the top of the local reference table jni_conv->ResetIterator(FrameOffset(out_arg_size)); // Register that will hold local indirect reference table if (jni_conv->IsCurrentParamInRegister()) { ManagedRegister jni_env = jni_conv->CurrentParamRegister(); DCHECK(!jni_env.Equals(jni_conv->InterproceduralScratchRegister())); __ LoadRawPtrFromThread(jni_env, Thread::JniEnvOffset()); // Frame[saved_local_ref_cookie_offset] = env->local_ref_cookie __ Copy(jni_conv->SavedLocalReferenceCookieOffset(), jni_env, JNIEnvExt::LocalRefCookieOffset(), jni_conv->InterproceduralScratchRegister(), 4); // env->local_ref_cookie = env->locals.segment_state __ Copy(jni_env, JNIEnvExt::LocalRefCookieOffset(), jni_env, JNIEnvExt::SegmentStateOffset(), jni_conv->InterproceduralScratchRegister(), 4); } else { FrameOffset jni_env = jni_conv->CurrentParamStackOffset(); __ CopyRawPtrFromThread(jni_env, Thread::JniEnvOffset(), jni_conv->InterproceduralScratchRegister()); // Frame[saved_local_ref_cookie_offset] = env->local_ref_cookie __ Copy(jni_conv->SavedLocalReferenceCookieOffset(), jni_env, JNIEnvExt::LocalRefCookieOffset(), jni_conv->InterproceduralScratchRegister(), 4); // env->local_ref_cookie = env->locals.segment_state __ Copy(jni_env, JNIEnvExt::LocalRefCookieOffset(), jni_env, JNIEnvExt::SegmentStateOffset(), jni_conv->InterproceduralScratchRegister(), 4); } // 9. Plant call to native code associated with method if (!jni_conv->IsMethodRegisterClobberedPreCall()) { // Method register shouldn't have been crushed by setting up outgoing // arguments __ Call(mr_conv->MethodRegister(), Method::NativeMethodOffset(), mr_conv->InterproceduralScratchRegister()); } else { __ Call(jni_conv->MethodStackOffset(), Method::NativeMethodOffset(), mr_conv->InterproceduralScratchRegister()); } // 10. Release lock for synchronized methods. if (is_synchronized) { mr_conv->ResetIterator(FrameOffset(frame_size+out_arg_size)); jni_conv->ResetIterator(FrameOffset(out_arg_size)); jni_conv->Next(); // Skip JNIEnv* // Save return value FrameOffset return_save_location = jni_conv->ReturnValueSaveLocation(); if (jni_conv->SizeOfReturnValue() != 0) { FrameOffset return_save_location = jni_conv->ReturnValueSaveLocation(); CHECK_LT(return_save_location.Uint32Value(), frame_size+out_arg_size); __ Store(return_save_location, jni_conv->ReturnRegister(), jni_conv->SizeOfReturnValue()); } // Get SIRT entry for 1st argument if (is_static) { FrameOffset sirt_offset = jni_conv->CurrentParamSirtEntryOffset(); if (jni_conv->IsCurrentParamOnStack()) { FrameOffset out_off = jni_conv->CurrentParamStackOffset(); __ CreateSirtEntry(out_off, sirt_offset, mr_conv->InterproceduralScratchRegister(), false); } else { ManagedRegister out_reg = jni_conv->CurrentParamRegister(); __ CreateSirtEntry(out_reg, sirt_offset, ManagedRegister::NoRegister(), false); } } else { CopyParameter(jni_asm.get(), mr_conv.get(), jni_conv.get(), frame_size, out_arg_size); } // Generate JNIEnv* in place and leave a copy in jni_env_register jni_conv->ResetIterator(FrameOffset(out_arg_size)); ManagedRegister jni_env_register = jni_conv->InterproceduralScratchRegister(); __ LoadRawPtrFromThread(jni_env_register, Thread::JniEnvOffset()); SetNativeParameter(jni_asm.get(), jni_conv.get(), jni_env_register); // Call JNIEnv->MonitorExit(object) __ LoadRawPtr(jni_env_register, jni_env_register, functions); __ Call(jni_env_register, monitor_exit, jni_conv->InterproceduralScratchRegister()); // Reload return value if (jni_conv->SizeOfReturnValue() != 0) { __ Load(jni_conv->ReturnRegister(), return_save_location, jni_conv->SizeOfReturnValue()); } } // 11. Release outgoing argument area __ DecreaseFrameSize(out_arg_size); mr_conv->ResetIterator(FrameOffset(frame_size)); jni_conv->ResetIterator(FrameOffset(0)); // 12. Transition from being in native to managed code, possibly entering a // safepoint // Don't clobber result CHECK(!jni_conv->InterproceduralScratchRegister().Equals(jni_conv->ReturnRegister())); // Location to preserve result on slow path, ensuring its within the frame FrameOffset return_save_location = jni_conv->ReturnValueSaveLocation(); CHECK(return_save_location.Uint32Value() < frame_size || jni_conv->SizeOfReturnValue() == 0); ChangeThreadState(jni_asm.get(), Thread::kRunnable, jni_conv->InterproceduralScratchRegister(), jni_conv->ReturnRegister(), return_save_location, jni_conv->SizeOfReturnValue()); // 13. Place result in correct register possibly loading from indirect // reference table if (jni_conv->IsReturnAReference()) { __ IncreaseFrameSize(out_arg_size); jni_conv->ResetIterator(FrameOffset(out_arg_size)); jni_conv->Next(); // Skip Thread* argument // Pass result as arg2 SetNativeParameter(jni_asm.get(), jni_conv.get(), jni_conv->ReturnRegister()); // Pass Thread* jni_conv->ResetIterator(FrameOffset(out_arg_size)); if (jni_conv->IsCurrentParamInRegister()) { __ GetCurrentThread(jni_conv->CurrentParamRegister()); __ Call(jni_conv->CurrentParamRegister(), Offset(OFFSETOF_MEMBER(Thread, pDecodeJObjectInThread)), jni_conv->InterproceduralScratchRegister()); } else { __ GetCurrentThread(jni_conv->CurrentParamStackOffset(), jni_conv->InterproceduralScratchRegister()); __ Call(ThreadOffset(OFFSETOF_MEMBER(Thread, pDecodeJObjectInThread)), jni_conv->InterproceduralScratchRegister()); } __ DecreaseFrameSize(out_arg_size); jni_conv->ResetIterator(FrameOffset(0)); } DCHECK_EQ(mr_conv->SizeOfReturnValue(), jni_conv->SizeOfReturnValue()); __ Move(mr_conv->ReturnRegister(), jni_conv->ReturnRegister(), mr_conv->SizeOfReturnValue()); // 14. Restore segment state and remove SIRT from thread { ManagedRegister jni_env = jni_conv->InterproceduralScratchRegister(); __ LoadRawPtrFromThread(jni_env, Thread::JniEnvOffset()); // env->locals.segment_state = env->local_ref_cookie __ Copy(jni_env, JNIEnvExt::SegmentStateOffset(), jni_env, JNIEnvExt::LocalRefCookieOffset(), jni_conv->ReturnScratchRegister(), 4); // env->local_ref_cookie = Frame[saved_local_ref_cookie_offset] __ Copy(jni_env, JNIEnvExt::LocalRefCookieOffset(), jni_conv->SavedLocalReferenceCookieOffset(), jni_conv->ReturnScratchRegister(), 4); } __ CopyRawPtrToThread(Thread::TopSirtOffset(), jni_conv->SirtLinkOffset(), jni_conv->InterproceduralScratchRegister()); // 15. Check for pending exception and forward if there __ ExceptionPoll(jni_conv->InterproceduralScratchRegister()); // 16. Remove activation if (is_synchronized) { __ RemoveFrame(frame_size, callee_save_regs); } else { // no need to restore callee save registers because we didn't // clobber them while locking the monitor. __ RemoveFrame(frame_size, std::vector()); } // 17. Finalize code generation __ EmitSlowPaths(); size_t cs = __ CodeSize(); std::vector managed_code(cs); MemoryRegion code(&managed_code[0], managed_code.size()); __ FinalizeInstructions(code); return new CompiledMethod(instruction_set, managed_code, frame_size, jni_conv->CoreSpillMask(), jni_conv->FpSpillMask()); } } // namespace art extern "C" art::CompiledMethod* ArtJniCompileMethod(art::Compiler& compiler, uint32_t access_flags, uint32_t method_idx, const art::ClassLoader* class_loader, const art::DexFile& dex_file) { return ArtJniCompileMethodInternal(compiler, access_flags, method_idx, class_loader, dex_file); }