/*
* 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 "jni_compiler.h"
#include <algorithm>
#include <fstream>
#include <ios>
#include <memory>
#include <vector>
#include "art_method.h"
#include "base/arena_allocator.h"
#include "base/arena_containers.h"
#include "base/enums.h"
#include "base/logging.h" // For VLOG.
#include "base/macros.h"
#include "base/malloc_arena_pool.h"
#include "base/memory_region.h"
#include "base/utils.h"
#include "calling_convention.h"
#include "class_linker.h"
#include "dwarf/debug_frame_opcode_writer.h"
#include "dex/dex_file-inl.h"
#include "driver/compiler_options.h"
#include "entrypoints/quick/quick_entrypoints.h"
#include "jni/jni_env_ext.h"
#include "thread.h"
#include "utils/arm/managed_register_arm.h"
#include "utils/arm64/managed_register_arm64.h"
#include "utils/assembler.h"
#include "utils/jni_macro_assembler.h"
#include "utils/managed_register.h"
#include "utils/x86/managed_register_x86.h"
#define __ jni_asm->
namespace art {
template <PointerSize kPointerSize>
static void CopyParameter(JNIMacroAssembler<kPointerSize>* jni_asm,
ManagedRuntimeCallingConvention* mr_conv,
JniCallingConvention* jni_conv);
template <PointerSize kPointerSize>
static void SetNativeParameter(JNIMacroAssembler<kPointerSize>* jni_asm,
JniCallingConvention* jni_conv,
ManagedRegister in_reg);
template <PointerSize kPointerSize>
static std::unique_ptr<JNIMacroAssembler<kPointerSize>> GetMacroAssembler(
ArenaAllocator* allocator, InstructionSet isa, const InstructionSetFeatures* features) {
return JNIMacroAssembler<kPointerSize>::Create(allocator, isa, features);
}
enum class JniEntrypoint {
kStart,
kEnd
};
template <PointerSize kPointerSize>
static ThreadOffset<kPointerSize> GetJniEntrypointThreadOffset(JniEntrypoint which,
bool reference_return,
bool is_synchronized,
bool is_fast_native) {
if (which == JniEntrypoint::kStart) { // JniMethodStart
ThreadOffset<kPointerSize> jni_start =
is_synchronized
? QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodStartSynchronized)
: (is_fast_native
? QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodFastStart)
: QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodStart));
return jni_start;
} else { // JniMethodEnd
ThreadOffset<kPointerSize> jni_end(-1);
if (reference_return) {
// Pass result.
jni_end = is_synchronized
? QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodEndWithReferenceSynchronized)
: (is_fast_native
? QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodFastEndWithReference)
: QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodEndWithReference));
} else {
jni_end = is_synchronized
? QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodEndSynchronized)
: (is_fast_native
? QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodFastEnd)
: QUICK_ENTRYPOINT_OFFSET(kPointerSize, pJniMethodEnd));
}
return jni_end;
}
}
// 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.
//
template <PointerSize kPointerSize>
static JniCompiledMethod ArtJniCompileMethodInternal(const CompilerOptions& compiler_options,
uint32_t access_flags,
uint32_t method_idx,
const DexFile& dex_file) {
const bool is_native = (access_flags & kAccNative) != 0;
CHECK(is_native);
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_options.GetInstructionSet();
const InstructionSetFeatures* instruction_set_features =
compiler_options.GetInstructionSetFeatures();
// i.e. if the method was annotated with @FastNative
const bool is_fast_native = (access_flags & kAccFastNative) != 0u;
// i.e. if the method was annotated with @CriticalNative
const bool is_critical_native = (access_flags & kAccCriticalNative) != 0u;
VLOG(jni) << "JniCompile: Method :: "
<< dex_file.PrettyMethod(method_idx, /* with signature */ true)
<< " :: access_flags = " << std::hex << access_flags << std::dec;
if (UNLIKELY(is_fast_native)) {
VLOG(jni) << "JniCompile: Fast native method detected :: "
<< dex_file.PrettyMethod(method_idx, /* with signature */ true);
}
if (UNLIKELY(is_critical_native)) {
VLOG(jni) << "JniCompile: Critical native method detected :: "
<< dex_file.PrettyMethod(method_idx, /* with signature */ true);
}
if (kIsDebugBuild) {
// Don't allow both @FastNative and @CriticalNative. They are mutually exclusive.
if (UNLIKELY(is_fast_native && is_critical_native)) {
LOG(FATAL) << "JniCompile: Method cannot be both @CriticalNative and @FastNative"
<< dex_file.PrettyMethod(method_idx, /* with_signature= */ true);
}
// @CriticalNative - extra checks:
// -- Don't allow virtual criticals
// -- Don't allow synchronized criticals
// -- Don't allow any objects as parameter or return value
if (UNLIKELY(is_critical_native)) {
CHECK(is_static)
<< "@CriticalNative functions cannot be virtual since that would"
<< "require passing a reference parameter (this), which is illegal "
<< dex_file.PrettyMethod(method_idx, /* with_signature= */ true);
CHECK(!is_synchronized)
<< "@CriticalNative functions cannot be synchronized since that would"
<< "require passing a (class and/or this) reference parameter, which is illegal "
<< dex_file.PrettyMethod(method_idx, /* with_signature= */ true);
for (size_t i = 0; i < strlen(shorty); ++i) {
CHECK_NE(Primitive::kPrimNot, Primitive::GetType(shorty[i]))
<< "@CriticalNative methods' shorty types must not have illegal references "
<< dex_file.PrettyMethod(method_idx, /* with_signature= */ true);
}
}
}
MallocArenaPool pool;
ArenaAllocator allocator(&pool);
// Calling conventions used to iterate over parameters to method
std::unique_ptr<JniCallingConvention> main_jni_conv =
JniCallingConvention::Create(&allocator,
is_static,
is_synchronized,
is_critical_native,
shorty,
instruction_set);
bool reference_return = main_jni_conv->IsReturnAReference();
std::unique_ptr<ManagedRuntimeCallingConvention> mr_conv(
ManagedRuntimeCallingConvention::Create(
&allocator, is_static, is_synchronized, shorty, instruction_set));
// Calling conventions to call into JNI method "end" possibly passing a returned reference, the
// method and the current thread.
const char* jni_end_shorty;
if (reference_return && is_synchronized) {
jni_end_shorty = "ILL";
} else if (reference_return) {
jni_end_shorty = "IL";
} else if (is_synchronized) {
jni_end_shorty = "VL";
} else {
jni_end_shorty = "V";
}
std::unique_ptr<JniCallingConvention> end_jni_conv(
JniCallingConvention::Create(&allocator,
is_static,
is_synchronized,
is_critical_native,
jni_end_shorty,
instruction_set));
// Assembler that holds generated instructions
std::unique_ptr<JNIMacroAssembler<kPointerSize>> jni_asm =
GetMacroAssembler<kPointerSize>(&allocator, instruction_set, instruction_set_features);
jni_asm->cfi().SetEnabled(compiler_options.GenerateAnyDebugInfo());
jni_asm->SetEmitRunTimeChecksInDebugMode(compiler_options.EmitRunTimeChecksInDebugMode());
// 1. Build the frame saving all callee saves, Method*, and PC return address.
// For @CriticalNative, this includes space for out args, otherwise just the managed frame.
const size_t managed_frame_size = main_jni_conv->FrameSize();
const size_t main_out_arg_size = main_jni_conv->OutFrameSize();
size_t current_frame_size = is_critical_native ? main_out_arg_size : managed_frame_size;
ManagedRegister method_register =
is_critical_native ? ManagedRegister::NoRegister() : mr_conv->MethodRegister();
ArrayRef<const ManagedRegister> callee_save_regs = main_jni_conv->CalleeSaveRegisters();
__ BuildFrame(current_frame_size, method_register, callee_save_regs);
DCHECK_EQ(jni_asm->cfi().GetCurrentCFAOffset(), static_cast<int>(current_frame_size));
if (LIKELY(!is_critical_native)) {
// Spill all register arguments.
// TODO: Pass these in a single call to let the assembler use multi-register stores.
// TODO: Spill native stack args straight to their stack locations (adjust SP earlier).
mr_conv->ResetIterator(FrameOffset(current_frame_size));
for (; mr_conv->HasNext(); mr_conv->Next()) {
if (mr_conv->IsCurrentParamInRegister()) {
size_t size = mr_conv->IsCurrentParamALongOrDouble() ? 8u : 4u;
__ Store(mr_conv->CurrentParamStackOffset(), mr_conv->CurrentParamRegister(), size);
}
}
// 2. Write out the end of the quick frames.
__ StoreStackPointerToThread(Thread::TopOfManagedStackOffset<kPointerSize>());
// NOTE: @CriticalNative does not need to store the stack pointer to the thread
// because garbage collections are disabled within the execution of a
// @CriticalNative method.
// (TODO: We could probably disable it for @FastNative too).
} // if (!is_critical_native)
// 3. Move frame down to allow space for out going args.
size_t current_out_arg_size = main_out_arg_size;
if (UNLIKELY(is_critical_native)) {
DCHECK_EQ(main_out_arg_size, current_frame_size);
} else {
__ IncreaseFrameSize(main_out_arg_size);
current_frame_size += main_out_arg_size;
}
// 4. Check if we need to go to the slow path to emit the read barrier for the declaring class
// in the method for a static call.
// Skip this for @CriticalNative because we're not passing a `jclass` to the native method.
std::unique_ptr<JNIMacroLabel> jclass_read_barrier_slow_path;
std::unique_ptr<JNIMacroLabel> jclass_read_barrier_return;
if (kUseReadBarrier && is_static && !is_critical_native) {
jclass_read_barrier_slow_path = __ CreateLabel();
jclass_read_barrier_return = __ CreateLabel();
// Check if gc_is_marking is set -- if it's not, we don't need a read barrier.
__ TestGcMarking(jclass_read_barrier_slow_path.get(), JNIMacroUnaryCondition::kNotZero);
// If marking, the slow path returns after the check.
__ Bind(jclass_read_barrier_return.get());
}
// 5. Call into appropriate JniMethodStart passing Thread* so that transition out of Runnable
// can occur. The result is the saved JNI local state that is restored by the exit call. We
// abuse the JNI calling convention here, that is guaranteed to support passing 2 pointer
// arguments.
constexpr size_t cookie_size = JniCallingConvention::SavedLocalReferenceCookieSize();
ManagedRegister saved_cookie_register = ManagedRegister::NoRegister();
if (LIKELY(!is_critical_native)) {
// Skip this for @CriticalNative methods. They do not call JniMethodStart.
ThreadOffset<kPointerSize> jni_start(
GetJniEntrypointThreadOffset<kPointerSize>(JniEntrypoint::kStart,
reference_return,
is_synchronized,
is_fast_native).SizeValue());
main_jni_conv->ResetIterator(FrameOffset(main_out_arg_size));
if (is_synchronized) {
// Pass object for locking.
if (is_static) {
// Pass the pointer to the method's declaring class as the first argument.
DCHECK_EQ(ArtMethod::DeclaringClassOffset().SizeValue(), 0u);
SetNativeParameter(jni_asm.get(), main_jni_conv.get(), method_register);
} else {
// TODO: Use the register that still holds the `this` reference.
mr_conv->ResetIterator(FrameOffset(current_frame_size));
FrameOffset this_offset = mr_conv->CurrentParamStackOffset();
if (main_jni_conv->IsCurrentParamOnStack()) {
FrameOffset out_off = main_jni_conv->CurrentParamStackOffset();
__ CreateJObject(out_off, this_offset, /*null_allowed=*/ false);
} else {
ManagedRegister out_reg = main_jni_conv->CurrentParamRegister();
__ CreateJObject(out_reg,
this_offset,
ManagedRegister::NoRegister(),
/*null_allowed=*/ false);
}
}
main_jni_conv->Next();
}
if (main_jni_conv->IsCurrentParamInRegister()) {
__ GetCurrentThread(main_jni_conv->CurrentParamRegister());
__ Call(main_jni_conv->CurrentParamRegister(), Offset(jni_start));
} else {
__ GetCurrentThread(main_jni_conv->CurrentParamStackOffset());
__ CallFromThread(jni_start);
}
method_register = ManagedRegister::NoRegister(); // Method register is clobbered.
if (is_synchronized) { // Check for exceptions from monitor enter.
__ ExceptionPoll(main_out_arg_size);
}
// Store into stack_frame[saved_cookie_offset] the return value of JniMethodStart.
saved_cookie_register = main_jni_conv->SavedLocalReferenceCookieRegister();
__ Move(saved_cookie_register, main_jni_conv->IntReturnRegister(), cookie_size);
}
// 6. Fill arguments.
if (UNLIKELY(is_critical_native)) {
ArenaVector<ArgumentLocation> src_args(allocator.Adapter());
ArenaVector<ArgumentLocation> dest_args(allocator.Adapter());
// Move the method pointer to the hidden argument register.
size_t pointer_size = static_cast<size_t>(kPointerSize);
dest_args.push_back(ArgumentLocation(main_jni_conv->HiddenArgumentRegister(), pointer_size));
src_args.push_back(ArgumentLocation(mr_conv->MethodRegister(), pointer_size));
// Move normal arguments to their locations.
mr_conv->ResetIterator(FrameOffset(current_frame_size));
main_jni_conv->ResetIterator(FrameOffset(main_out_arg_size));
for (; mr_conv->HasNext(); mr_conv->Next(), main_jni_conv->Next()) {
DCHECK(main_jni_conv->HasNext());
size_t size = mr_conv->IsCurrentParamALongOrDouble() ? 8u : 4u;
src_args.push_back(mr_conv->IsCurrentParamInRegister()
? ArgumentLocation(mr_conv->CurrentParamRegister(), size)
: ArgumentLocation(mr_conv->CurrentParamStackOffset(), size));
dest_args.push_back(main_jni_conv->IsCurrentParamInRegister()
? ArgumentLocation(main_jni_conv->CurrentParamRegister(), size)
: ArgumentLocation(main_jni_conv->CurrentParamStackOffset(), size));
}
DCHECK(!main_jni_conv->HasNext());
__ MoveArguments(ArrayRef<ArgumentLocation>(dest_args), ArrayRef<ArgumentLocation>(src_args));
} else {
// 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(current_frame_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.
// TODO: This is currently useless as all archs spill args when building the frame.
// To avoid the full spilling, we would have to do one pass before the BuildFrame()
// to determine which arg registers are clobbered before they are needed.
for (uint32_t i = 0; i < args_count; ++i) {
mr_conv->ResetIterator(FrameOffset(current_frame_size));
main_jni_conv->ResetIterator(FrameOffset(main_out_arg_size));
// Skip the extra JNI parameters for now.
main_jni_conv->Next(); // Skip JNIEnv*.
if (is_static) {
main_jni_conv->Next(); // Skip Class for now.
}
// Skip to the argument we're interested in.
for (uint32_t j = 0; j < args_count - i - 1; ++j) {
mr_conv->Next();
main_jni_conv->Next();
}
CopyParameter(jni_asm.get(), mr_conv.get(), main_jni_conv.get());
}
// 7. For static method, create jclass argument as a pointer to the method's declaring class.
if (is_static) {
main_jni_conv->ResetIterator(FrameOffset(main_out_arg_size));
main_jni_conv->Next(); // Skip JNIEnv*
// Load reference to the method's declaring class. The method register has been
// clobbered by the above call, so we need to load the method from the stack.
FrameOffset method_offset =
FrameOffset(current_out_arg_size + mr_conv->MethodStackOffset().SizeValue());
DCHECK_EQ(ArtMethod::DeclaringClassOffset().SizeValue(), 0u);
if (main_jni_conv->IsCurrentParamOnStack()) {
FrameOffset out_off = main_jni_conv->CurrentParamStackOffset();
__ Copy(out_off, method_offset, static_cast<size_t>(kPointerSize));
// TODO(x86): Get hold of the register used to copy the method pointer,
// so that we can use it also for loading the method entrypoint below.
} else {
ManagedRegister out_reg = main_jni_conv->CurrentParamRegister();
__ Load(out_reg, method_offset, static_cast<size_t>(kPointerSize));
// Reuse the register also for loading the method entrypoint below.
method_register = out_reg;
}
}
// Set the iterator back to the incoming Method*.
main_jni_conv->ResetIterator(FrameOffset(main_out_arg_size));
// 8. Create 1st argument, the JNI environment ptr.
// Register that will hold local indirect reference table
if (main_jni_conv->IsCurrentParamInRegister()) {
ManagedRegister jni_env = main_jni_conv->CurrentParamRegister();
__ LoadRawPtrFromThread(jni_env, Thread::JniEnvOffset<kPointerSize>());
} else {
FrameOffset jni_env = main_jni_conv->CurrentParamStackOffset();
__ CopyRawPtrFromThread(jni_env, Thread::JniEnvOffset<kPointerSize>());
}
}
// 9. Plant call to native code associated with method.
MemberOffset jni_entrypoint_offset =
ArtMethod::EntryPointFromJniOffset(InstructionSetPointerSize(instruction_set));
if (UNLIKELY(is_critical_native)) {
if (main_jni_conv->UseTailCall()) {
__ Jump(main_jni_conv->HiddenArgumentRegister(), jni_entrypoint_offset);
} else {
__ Call(main_jni_conv->HiddenArgumentRegister(), jni_entrypoint_offset);
}
} else {
if (method_register.IsRegister()) {
__ Call(method_register, jni_entrypoint_offset);
} else {
__ Call(FrameOffset(current_out_arg_size + mr_conv->MethodStackOffset().SizeValue()),
jni_entrypoint_offset);
}
}
// 10. Fix differences in result widths.
if (main_jni_conv->RequiresSmallResultTypeExtension()) {
DCHECK(main_jni_conv->HasSmallReturnType());
CHECK(!is_critical_native || !main_jni_conv->UseTailCall());
if (main_jni_conv->GetReturnType() == Primitive::kPrimByte ||
main_jni_conv->GetReturnType() == Primitive::kPrimShort) {
__ SignExtend(main_jni_conv->ReturnRegister(),
Primitive::ComponentSize(main_jni_conv->GetReturnType()));
} else {
CHECK(main_jni_conv->GetReturnType() == Primitive::kPrimBoolean ||
main_jni_conv->GetReturnType() == Primitive::kPrimChar);
__ ZeroExtend(main_jni_conv->ReturnRegister(),
Primitive::ComponentSize(main_jni_conv->GetReturnType()));
}
}
// 11. Process return value
bool spill_return_value = main_jni_conv->SpillsReturnValue();
FrameOffset return_save_location =
spill_return_value ? main_jni_conv->ReturnValueSaveLocation() : FrameOffset(0);
if (spill_return_value) {
DCHECK(!is_critical_native);
// For normal JNI, store the return value on the stack because the call to
// JniMethodEnd will clobber the return value. It will be restored in (13).
CHECK_LT(return_save_location.Uint32Value(), current_frame_size);
__ Store(return_save_location,
main_jni_conv->ReturnRegister(),
main_jni_conv->SizeOfReturnValue());
} else if (UNLIKELY(is_critical_native) && main_jni_conv->SizeOfReturnValue() != 0) {
// For @CriticalNative only,
// move the JNI return register into the managed return register (if they don't match).
ManagedRegister jni_return_reg = main_jni_conv->ReturnRegister();
ManagedRegister mr_return_reg = mr_conv->ReturnRegister();
// Check if the JNI return register matches the managed return register.
// If they differ, only then do we have to do anything about it.
// Otherwise the return value is already in the right place when we return.
if (!jni_return_reg.Equals(mr_return_reg)) {
CHECK(!main_jni_conv->UseTailCall());
// This is typically only necessary on ARM32 due to native being softfloat
// while managed is hardfloat.
// -- For example VMOV {r0, r1} -> D0; VMOV r0 -> S0.
__ Move(mr_return_reg, jni_return_reg, main_jni_conv->SizeOfReturnValue());
} else if (jni_return_reg.IsNoRegister() && mr_return_reg.IsNoRegister()) {
// Check that if the return value is passed on the stack for some reason,
// that the size matches.
CHECK_EQ(main_jni_conv->SizeOfReturnValue(), mr_conv->SizeOfReturnValue());
}
}
if (LIKELY(!is_critical_native)) {
// Increase frame size for out args if needed by the end_jni_conv.
const size_t end_out_arg_size = end_jni_conv->OutFrameSize();
if (end_out_arg_size > current_out_arg_size) {
size_t out_arg_size_diff = end_out_arg_size - current_out_arg_size;
current_out_arg_size = end_out_arg_size;
__ IncreaseFrameSize(out_arg_size_diff);
current_frame_size += out_arg_size_diff;
return_save_location = FrameOffset(return_save_location.SizeValue() + out_arg_size_diff);
}
end_jni_conv->ResetIterator(FrameOffset(end_out_arg_size));
// 12. Call JniMethodEnd
ThreadOffset<kPointerSize> jni_end(
GetJniEntrypointThreadOffset<kPointerSize>(JniEntrypoint::kEnd,
reference_return,
is_synchronized,
is_fast_native).SizeValue());
if (reference_return) {
// Pass result.
SetNativeParameter(jni_asm.get(), end_jni_conv.get(), end_jni_conv->ReturnRegister());
end_jni_conv->Next();
}
// Pass saved local reference state.
if (end_jni_conv->IsCurrentParamOnStack()) {
FrameOffset out_off = end_jni_conv->CurrentParamStackOffset();
__ Store(out_off, saved_cookie_register, cookie_size);
} else {
ManagedRegister out_reg = end_jni_conv->CurrentParamRegister();
__ Move(out_reg, saved_cookie_register, cookie_size);
}
end_jni_conv->Next();
if (is_synchronized) {
// Pass object for unlocking.
if (is_static) {
// Load reference to the method's declaring class. The method register has been
// clobbered by the above call, so we need to load the method from the stack.
FrameOffset method_offset =
FrameOffset(current_out_arg_size + mr_conv->MethodStackOffset().SizeValue());
DCHECK_EQ(ArtMethod::DeclaringClassOffset().SizeValue(), 0u);
if (end_jni_conv->IsCurrentParamOnStack()) {
FrameOffset out_off = end_jni_conv->CurrentParamStackOffset();
__ Copy(out_off, method_offset, static_cast<size_t>(kPointerSize));
} else {
ManagedRegister out_reg = end_jni_conv->CurrentParamRegister();
__ Load(out_reg, method_offset, static_cast<size_t>(kPointerSize));
}
} else {
mr_conv->ResetIterator(FrameOffset(current_frame_size));
FrameOffset this_offset = mr_conv->CurrentParamStackOffset();
if (end_jni_conv->IsCurrentParamOnStack()) {
FrameOffset out_off = end_jni_conv->CurrentParamStackOffset();
__ CreateJObject(out_off, this_offset, /*null_allowed=*/ false);
} else {
ManagedRegister out_reg = end_jni_conv->CurrentParamRegister();
__ CreateJObject(out_reg,
this_offset,
ManagedRegister::NoRegister(),
/*null_allowed=*/ false);
}
}
end_jni_conv->Next();
}
if (end_jni_conv->IsCurrentParamInRegister()) {
__ GetCurrentThread(end_jni_conv->CurrentParamRegister());
__ Call(end_jni_conv->CurrentParamRegister(), Offset(jni_end));
} else {
__ GetCurrentThread(end_jni_conv->CurrentParamStackOffset());
__ CallFromThread(jni_end);
}
// 13. Reload return value
if (spill_return_value) {
__ Load(mr_conv->ReturnRegister(), return_save_location, mr_conv->SizeOfReturnValue());
}
} // if (!is_critical_native)
// 14. Move frame up now we're done with the out arg space.
// @CriticalNative remove out args together with the frame in RemoveFrame().
if (LIKELY(!is_critical_native)) {
__ DecreaseFrameSize(current_out_arg_size);
current_frame_size -= current_out_arg_size;
}
// 15. Process pending exceptions from JNI call or monitor exit.
// @CriticalNative methods do not need exception poll in the stub.
if (LIKELY(!is_critical_native)) {
__ ExceptionPoll(/* stack_adjust= */ 0);
}
// 16. Remove activation - need to restore callee save registers since the GC may have changed
// them.
DCHECK_EQ(jni_asm->cfi().GetCurrentCFAOffset(), static_cast<int>(current_frame_size));
if (LIKELY(!is_critical_native) || !main_jni_conv->UseTailCall()) {
// We expect the compiled method to possibly be suspended during its
// execution, except in the case of a CriticalNative method.
bool may_suspend = !is_critical_native;
__ RemoveFrame(current_frame_size, callee_save_regs, may_suspend);
DCHECK_EQ(jni_asm->cfi().GetCurrentCFAOffset(), static_cast<int>(current_frame_size));
}
// 17. Read barrier slow path for the declaring class in the method for a static call.
// Skip this for @CriticalNative because we're not passing a `jclass` to the native method.
if (kUseReadBarrier && is_static && !is_critical_native) {
__ Bind(jclass_read_barrier_slow_path.get());
// We do the marking check after adjusting for outgoing arguments. That ensures that
// we have space available for at least two params in case we need to pass the read
// barrier parameters on stack (only x86). But that means we must adjust the CFI
// offset accordingly as it does not include the outgoing args after `RemoveFrame().
if (main_out_arg_size != 0) {
// Note: The DW_CFA_def_cfa_offset emitted by `RemoveFrame()` above
// is useless when it is immediatelly overridden here but avoiding
// it adds a lot of code complexity for minimal gain.
jni_asm->cfi().AdjustCFAOffset(main_out_arg_size);
}
// We enter the slow path with the method register unclobbered.
method_register = mr_conv->MethodRegister();
// Construct slow path for read barrier:
//
// Call into the runtime's ReadBarrierJni and have it fix up
// the object address if it was moved.
ThreadOffset<kPointerSize> read_barrier = QUICK_ENTRYPOINT_OFFSET(kPointerSize,
pReadBarrierJni);
main_jni_conv->ResetIterator(FrameOffset(main_out_arg_size));
// Pass the pointer to the method's declaring class as the first argument.
DCHECK_EQ(ArtMethod::DeclaringClassOffset().SizeValue(), 0u);
SetNativeParameter(jni_asm.get(), main_jni_conv.get(), method_register);
main_jni_conv->Next();
// Pass the current thread as the second argument and call.
if (main_jni_conv->IsCurrentParamInRegister()) {
__ GetCurrentThread(main_jni_conv->CurrentParamRegister());
__ Call(main_jni_conv->CurrentParamRegister(), Offset(read_barrier));
} else {
__ GetCurrentThread(main_jni_conv->CurrentParamStackOffset());
__ CallFromThread(read_barrier);
}
if (is_synchronized) {
// Reload the method pointer in the slow path because it is needed
// as an argument for the `JniMethodStartSynchronized`.
__ Load(method_register,
FrameOffset(main_out_arg_size + mr_conv->MethodStackOffset().SizeValue()),
static_cast<size_t>(kPointerSize));
}
// Return to main path.
__ Jump(jclass_read_barrier_return.get());
// Undo the CFI offset adjustment at the start of the slow path.
if (main_out_arg_size != 0) {
jni_asm->cfi().AdjustCFAOffset(-main_out_arg_size);
}
}
// 18. Finalize code generation
__ FinalizeCode();
size_t cs = __ CodeSize();
std::vector<uint8_t> managed_code(cs);
MemoryRegion code(&managed_code[0], managed_code.size());
__ FinalizeInstructions(code);
return JniCompiledMethod(instruction_set,
std::move(managed_code),
managed_frame_size,
main_jni_conv->CoreSpillMask(),
main_jni_conv->FpSpillMask(),
ArrayRef<const uint8_t>(*jni_asm->cfi().data()));
}
// Copy a single parameter from the managed to the JNI calling convention.
template <PointerSize kPointerSize>
static void CopyParameter(JNIMacroAssembler<kPointerSize>* jni_asm,
ManagedRuntimeCallingConvention* mr_conv,
JniCallingConvention* jni_conv) {
// We spilled all registers, so use stack locations.
// TODO: Move args in registers for @CriticalNative.
bool input_in_reg = false; // mr_conv->IsCurrentParamInRegister();
bool output_in_reg = jni_conv->IsCurrentParamInRegister();
FrameOffset spilled_reference_offset(0);
bool null_allowed = false;
bool ref_param = jni_conv->IsCurrentParamAReference();
CHECK(!ref_param || mr_conv->IsCurrentParamAReference());
if (output_in_reg) { // output shouldn't straddle registers and stack
CHECK(!jni_conv->IsCurrentParamOnStack());
} else {
CHECK(jni_conv->IsCurrentParamOnStack());
}
// References are spilled to caller's reserved out vreg area.
if (ref_param) {
null_allowed = mr_conv->IsCurrentArgPossiblyNull();
// Compute spilled reference offset. Note that null is spilled but the jobject
// passed to the native code must be null (not a pointer into the spilled value
// as with regular references).
spilled_reference_offset = mr_conv->CurrentParamStackOffset();
// Check that spilled reference offset is in the spill area in the caller's frame.
CHECK_GT(spilled_reference_offset.Uint32Value(), mr_conv->GetDisplacement().Uint32Value());
}
if (input_in_reg && output_in_reg) {
ManagedRegister in_reg = mr_conv->CurrentParamRegister();
ManagedRegister out_reg = jni_conv->CurrentParamRegister();
if (ref_param) {
__ CreateJObject(out_reg, spilled_reference_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) {
__ CreateJObject(out_off, spilled_reference_offset, 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, 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(), mr_conv->GetDisplacement().Uint32Value());
if (ref_param) {
__ CreateJObject(out_reg,
spilled_reference_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 part dedicated to out args.
CHECK_LT(out_off.Uint32Value(), jni_conv->GetDisplacement().Uint32Value());
if (ref_param) {
// TODO: recycle value in in_reg rather than reload from spill slot.
__ CreateJObject(out_off, spilled_reference_offset, 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);
}
}
}
}
template <PointerSize kPointerSize>
static void SetNativeParameter(JNIMacroAssembler<kPointerSize>* 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());
}
}
}
JniCompiledMethod ArtQuickJniCompileMethod(const CompilerOptions& compiler_options,
uint32_t access_flags,
uint32_t method_idx,
const DexFile& dex_file) {
if (Is64BitInstructionSet(compiler_options.GetInstructionSet())) {
return ArtJniCompileMethodInternal<PointerSize::k64>(
compiler_options, access_flags, method_idx, dex_file);
} else {
return ArtJniCompileMethodInternal<PointerSize::k32>(
compiler_options, access_flags, method_idx, dex_file);
}
}
} // namespace art