// Check all the formats of native implementation name to see if there is one
// for the specified method.
address NativeLookup::lookup_entry(methodHandle method, bool& in_base_library, TRAPS) {
address entry = NULL;
in_base_library = false;
// Compute pure name
char* pure_name = pure_jni_name(method);
//计算指定本地方法的参数数量
int args_size = 1 // JNIEnv
+ (method->is_static() ? 1 : 0) // class for static methods
+ method->size_of_parameters(); // actual parameters
// 1) Try JNI short style
entry = lookup_style(method, pure_name, "", args_size, true, in_base_library, CHECK_NULL);
if (entry != NULL) return entry;
// Compute long name
char* long_name = long_jni_name(method);
// 2) Try JNI long style
entry = lookup_style(method, pure_name, long_name, args_size, true, in_base_library, CHECK_NULL);
if (entry != NULL) return entry;
// 3) Try JNI short style without os prefix/suffix
entry = lookup_style(method, pure_name, "", args_size, false, in_base_library, CHECK_NULL);
if (entry != NULL) return entry;
// 4) Try JNI long style without os prefix/suffix
entry = lookup_style(method, pure_name, long_name, args_size, false, in_base_library, CHECK_NULL);
return entry; // NULL indicates not found
}
AbstractInterpreter::MethodKind AbstractInterpreter::method_kind(methodHandle m) {
// Abstract method?
if (m->is_abstract()) return abstract;
// Invoker for method handles?
if (m->is_method_handle_invoke()) return method_handle;
// Native method?
// Note: This test must come _before_ the test for intrinsic
// methods. See also comments below.
if (m->is_native()) {
assert(!m->is_method_handle_invoke(), "overlapping bits here, watch out");
return m->is_synchronized() ? native_synchronized : native;
}
// Synchronized?
if (m->is_synchronized()) {
return zerolocals_synchronized;
}
if (RegisterFinalizersAtInit && m->code_size() == 1 &&
m->intrinsic_id() == vmIntrinsics::_Object_init) {
// We need to execute the special return bytecode to check for
// finalizer registration so create a normal frame.
return zerolocals;
}
// Empty method?
if (m->is_empty_method()) {
return empty;
}
// Special intrinsic method?
// Note: This test must come _after_ the test for native methods,
// otherwise we will run into problems with JDK 1.2, see also
// AbstractInterpreterGenerator::generate_method_entry() for
// for details.
switch (m->intrinsic_id()) {
case vmIntrinsics::_dsin : return java_lang_math_sin ;
case vmIntrinsics::_dcos : return java_lang_math_cos ;
case vmIntrinsics::_dtan : return java_lang_math_tan ;
case vmIntrinsics::_dabs : return java_lang_math_abs ;
case vmIntrinsics::_dsqrt : return java_lang_math_sqrt ;
case vmIntrinsics::_dlog : return java_lang_math_log ;
case vmIntrinsics::_dlog10: return java_lang_math_log10;
case vmIntrinsics::_Reference_get:
return java_lang_ref_reference_get;
}
// Accessor method?
if (m->is_accessor()) {
assert(m->size_of_parameters() == 1, "fast code for accessors assumes parameter size = 1");
return accessor;
}
// Note: for now: zero locals for all non-empty methods
return zerolocals;
}
// Initialize the methodDataOop corresponding to a given method.
void methodDataOopDesc::initialize(methodHandle method) {
ResourceMark rm;
// Set the method back-pointer.
_method = method();
set_creation_mileage(mileage_of(method()));
// Initialize flags and trap history.
_nof_decompiles = 0;
_nof_overflow_recompiles = 0;
_nof_overflow_traps = 0;
assert(sizeof(_trap_hist) % sizeof(HeapWord) == 0, "align");
Copy::zero_to_words((HeapWord*) &_trap_hist,
sizeof(_trap_hist) / sizeof(HeapWord));
// Go through the bytecodes and allocate and initialize the
// corresponding data cells.
int data_size = 0;
int empty_bc_count = 0; // number of bytecodes lacking data
BytecodeStream stream(method);
Bytecodes::Code c;
while ((c = stream.next()) >= 0) {
int size_in_bytes = initialize_data(&stream, data_size);
data_size += size_in_bytes;
if (size_in_bytes == 0) empty_bc_count += 1;
}
_data_size = data_size;
int object_size = in_bytes(data_offset()) + data_size;
// Add some extra DataLayout cells (at least one) to track stray traps.
int extra_data_count = compute_extra_data_count(data_size, empty_bc_count);
int extra_size = extra_data_count * DataLayout::compute_size_in_bytes(0);
// Add a cell to record information about modified arguments.
// Set up _args_modified array after traps cells so that
// the code for traps cells works.
DataLayout *dp = data_layout_at(data_size + extra_size);
int arg_size = method->size_of_parameters();
dp->initialize(DataLayout::arg_info_data_tag, 0, arg_size+1);
object_size += extra_size + DataLayout::compute_size_in_bytes(arg_size+1);
// Set an initial hint. Don't use set_hint_di() because
// first_di() may be out of bounds if data_size is 0.
// In that situation, _hint_di is never used, but at
// least well-defined.
_hint_di = first_di();
post_initialize(&stream);
set_object_is_parsable(object_size);
}
// Check all the formats of native implementation name to see if there is one
// for the specified method.
address NativeLookup::lookup_critical_entry(methodHandle method) {
if (!CriticalJNINatives) return NULL;
if (method->is_synchronized() ||
!method->is_static()) {
// Only static non-synchronized methods are allowed
return NULL;
}
ResourceMark rm;
address entry = NULL;
Symbol* signature = method->signature();
for (int end = 0; end < signature->utf8_length(); end++) {
if (signature->byte_at(end) == 'L') {
// Don't allow object types
return NULL;
}
}
// Compute critical name
char* critical_name = critical_jni_name(method);
// Compute argument size
int args_size = 1 // JNIEnv
+ (method->is_static() ? 1 : 0) // class for static methods
+ method->size_of_parameters(); // actual parameters
// 1) Try JNI short style
entry = lookup_critical_style(method, critical_name, "", args_size, true);
if (entry != NULL) return entry;
// Compute long name
char* long_name = long_jni_name(method);
// 2) Try JNI long style
entry = lookup_critical_style(method, critical_name, long_name, args_size, true);
if (entry != NULL) return entry;
// 3) Try JNI short style without os prefix/suffix
entry = lookup_critical_style(method, critical_name, "", args_size, false);
if (entry != NULL) return entry;
// 4) Try JNI long style without os prefix/suffix
entry = lookup_critical_style(method, critical_name, long_name, args_size, false);
return entry; // NULL indicates not found
}
// Compute the size of the methodDataOop necessary to store
// profiling information about a given method. Size is in bytes.
int methodDataOopDesc::compute_allocation_size_in_bytes(methodHandle method) {
int data_size = 0;
BytecodeStream stream(method);
Bytecodes::Code c;
int empty_bc_count = 0; // number of bytecodes lacking data
while ((c = stream.next()) >= 0) {
int size_in_bytes = compute_data_size(&stream);
data_size += size_in_bytes;
if (size_in_bytes == 0) empty_bc_count += 1;
}
int object_size = in_bytes(data_offset()) + data_size;
// Add some extra DataLayout cells (at least one) to track stray traps.
int extra_data_count = compute_extra_data_count(data_size, empty_bc_count);
object_size += extra_data_count * DataLayout::compute_size_in_bytes(0);
// Add a cell to record information about modified arguments.
int arg_size = method->size_of_parameters();
object_size += DataLayout::compute_size_in_bytes(arg_size+1);
return object_size;
}
uint64_t fingerprint() {
// See if we fingerprinted this method already
if (mh->constMethod()->fingerprint() != CONST64(0)) {
return mh->constMethod()->fingerprint();
}
if (mh->size_of_parameters() > max_size_of_parameters ) {
_fingerprint = UCONST64(-1);
mh->constMethod()->set_fingerprint(_fingerprint);
return _fingerprint;
}
assert( (int)mh->result_type() <= (int)result_feature_mask, "bad result type");
_fingerprint = mh->result_type();
_fingerprint <<= static_feature_size;
if (mh->is_static()) _fingerprint |= 1;
_shift_count = result_feature_size + static_feature_size;
iterate_parameters();
_fingerprint |= ((uint64_t)done_parm) << _shift_count;// mark end of sig
mh->constMethod()->set_fingerprint(_fingerprint);
return _fingerprint;
}
void ConstantPoolCacheEntry::set_method_handle_common(constantPoolHandle cpool,
Bytecodes::Code invoke_code,
const CallInfo &call_info) {
// NOTE: This CPCE can be the subject of data races.
// There are three words to update: flags, refs[f2], f1 (in that order).
// Writers must store all other values before f1.
// Readers must test f1 first for non-null before reading other fields.
// Competing writers must acquire exclusive access via a lock.
// A losing writer waits on the lock until the winner writes f1 and leaves
// the lock, so that when the losing writer returns, he can use the linked
// cache entry.
MonitorLockerEx ml(cpool->lock());
if (!is_f1_null()) {
return;
}
const methodHandle adapter = call_info.resolved_method();
const Handle appendix = call_info.resolved_appendix();
const Handle method_type = call_info.resolved_method_type();
const bool has_appendix = appendix.not_null();
const bool has_method_type = method_type.not_null();
// Write the flags.
set_method_flags(as_TosState(adapter->result_type()),
((has_appendix ? 1 : 0) << has_appendix_shift ) |
((has_method_type ? 1 : 0) << has_method_type_shift) |
( 1 << is_final_shift ),
adapter->size_of_parameters());
if (TraceInvokeDynamic) {
tty->print_cr("set_method_handle bc=%d appendix="PTR_FORMAT"%s method_type="PTR_FORMAT"%s method="PTR_FORMAT" ",
invoke_code,
(void *)appendix(), (has_appendix ? "" : " (unused)"),
(void *)method_type(), (has_method_type ? "" : " (unused)"),
(intptr_t)adapter());
adapter->print();
if (has_appendix) appendix()->print();
}
// Method handle invokes and invokedynamic sites use both cp cache words.
// refs[f2], if not null, contains a value passed as a trailing argument to the adapter.
// In the general case, this could be the call site's MethodType,
// for use with java.lang.Invokers.checkExactType, or else a CallSite object.
// f1 contains the adapter method which manages the actual call.
// In the general case, this is a compiled LambdaForm.
// (The Java code is free to optimize these calls by binding other
// sorts of methods and appendices to call sites.)
// JVM-level linking is via f1, as if for invokespecial, and signatures are erased.
// The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
// Even with the appendix, the method will never take more than 255 parameter slots.
//
// This means that given a call site like (List)mh.invoke("foo"),
// the f1 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
// not '(Ljava/lang/String;)Ljava/util/List;'.
// The fact that String and List are involved is encoded in the MethodType in refs[f2].
// This allows us to create fewer method oops, while keeping type safety.
//
objArrayHandle resolved_references = cpool->resolved_references();
// Store appendix, if any.
if (has_appendix) {
const int appendix_index = f2_as_index() + _indy_resolved_references_appendix_offset;
assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
assert(resolved_references->obj_at(appendix_index) == NULL, "init just once");
resolved_references->obj_at_put(appendix_index, appendix());
}
// Store MethodType, if any.
if (has_method_type) {
const int method_type_index = f2_as_index() + _indy_resolved_references_method_type_offset;
assert(method_type_index >= 0 && method_type_index < resolved_references->length(), "oob");
assert(resolved_references->obj_at(method_type_index) == NULL, "init just once");
resolved_references->obj_at_put(method_type_index, method_type());
}
release_set_f1(adapter()); // This must be the last one to set (see NOTE above)!
// The interpreter assembly code does not check byte_2,
// but it is used by is_resolved, method_if_resolved, etc.
set_bytecode_1(invoke_code);
NOT_PRODUCT(verify(tty));
if (TraceInvokeDynamic) {
this->print(tty, 0);
}
}
void ConstantPoolCacheEntry::set_method_handle_common(constantPoolHandle cpool,
Bytecodes::Code invoke_code,
methodHandle adapter,
Handle appendix, Handle method_type) {
// NOTE: This CPCE can be the subject of data races.
// There are three words to update: flags, f2, f1 (in that order).
// Writers must store all other values before f1.
// Readers must test f1 first for non-null before reading other fields.
// Competing writers must acquire exclusive access via a lock.
// A losing writer waits on the lock until the winner writes f1 and leaves
// the lock, so that when the losing writer returns, he can use the linked
// cache entry.
Thread* THREAD = Thread::current();
ObjectLocker ol(cpool, THREAD);
if (!is_f1_null()) {
return;
}
const bool has_appendix = appendix.not_null();
const bool has_method_type = method_type.not_null();
if (!has_appendix) {
// The extra argument is not used, but we need a non-null value to signify linkage state.
// Set it to something benign that will never leak memory.
appendix = Universe::void_mirror();
}
// Write the flags.
set_method_flags(as_TosState(adapter->result_type()),
((has_appendix ? 1 : 0) << has_appendix_shift) |
((has_method_type ? 1 : 0) << has_method_type_shift) |
( 1 << is_vfinal_shift) |
( 1 << is_final_shift),
adapter->size_of_parameters());
if (TraceInvokeDynamic) {
tty->print_cr("set_method_handle bc=%d appendix="PTR_FORMAT"%s method_type="PTR_FORMAT"%s method="PTR_FORMAT" ",
invoke_code,
(intptr_t)appendix(), (has_appendix ? "" : " (unused)"),
(intptr_t)method_type(), (has_method_type ? "" : " (unused)"),
(intptr_t)adapter());
adapter->print();
if (has_appendix) appendix()->print();
}
// Method handle invokes and invokedynamic sites use both cp cache words.
// f1, if not null, contains a value passed as a trailing argument to the adapter.
// In the general case, this could be the call site's MethodType,
// for use with java.lang.Invokers.checkExactType, or else a CallSite object.
// f2 contains the adapter method which manages the actual call.
// In the general case, this is a compiled LambdaForm.
// (The Java code is free to optimize these calls by binding other
// sorts of methods and appendices to call sites.)
// JVM-level linking is via f2, as if for invokevfinal, and signatures are erased.
// The appendix argument (if any) is added to the signature, and is counted in the parameter_size bits.
// In principle this means that the method (with appendix) could take up to 256 parameter slots.
//
// This means that given a call site like (List)mh.invoke("foo"),
// the f2 method has signature '(Ljl/Object;Ljl/invoke/MethodType;)Ljl/Object;',
// not '(Ljava/lang/String;)Ljava/util/List;'.
// The fact that String and List are involved is encoded in the MethodType in f1.
// This allows us to create fewer method oops, while keeping type safety.
//
set_f2_as_vfinal_method(adapter());
// Store MethodType, if any.
if (has_method_type) {
ConstantPoolCacheEntry* e2 = cpool->cache()->find_secondary_entry_for(this);
// Write the flags.
e2->set_method_flags(as_TosState(adapter->result_type()),
((has_method_type ? 1 : 0) << has_method_type_shift) |
( 1 << is_vfinal_shift) |
( 1 << is_final_shift),
adapter->size_of_parameters());
e2->release_set_f1(method_type());
}
assert(appendix.not_null(), "needed for linkage state");
release_set_f1(appendix()); // This must be the last one to set (see NOTE above)!
if (!is_secondary_entry()) {
// The interpreter assembly code does not check byte_2,
// but it is used by is_resolved, method_if_resolved, etc.
set_bytecode_2(invoke_code);
}
NOT_PRODUCT(verify(tty));
if (TraceInvokeDynamic) {
this->print(tty, 0);
}
}
AbstractInterpreter::MethodKind AbstractInterpreter::method_kind(methodHandle m) {
// Abstract method?
if (m->is_abstract()) return abstract;
// Method handle primitive?
if (m->is_method_handle_intrinsic()) {
vmIntrinsics::ID id = m->intrinsic_id();
assert(MethodHandles::is_signature_polymorphic(id), "must match an intrinsic");
MethodKind kind = (MethodKind)( method_handle_invoke_FIRST +
((int)id - vmIntrinsics::FIRST_MH_SIG_POLY) );
assert(kind <= method_handle_invoke_LAST, "parallel enum ranges");
return kind;
}
#ifndef CC_INTERP
if (UseCRC32Intrinsics && m->is_native()) {
// Use optimized stub code for CRC32 native methods.
switch (m->intrinsic_id()) {
case vmIntrinsics::_updateCRC32 : return java_util_zip_CRC32_update;
case vmIntrinsics::_updateBytesCRC32 : return java_util_zip_CRC32_updateBytes;
case vmIntrinsics::_updateByteBufferCRC32 : return java_util_zip_CRC32_updateByteBuffer;
}
}
#endif
// Native method?
// Note: This test must come _before_ the test for intrinsic
// methods. See also comments below.
if (m->is_native()) {
assert(!m->is_method_handle_intrinsic(), "overlapping bits here, watch out");
return m->is_synchronized() ? native_synchronized : native;
}
// Synchronized?
if (m->is_synchronized()) {
return zerolocals_synchronized;
}
if (RegisterFinalizersAtInit && m->code_size() == 1 &&
m->intrinsic_id() == vmIntrinsics::_Object_init) {
// We need to execute the special return bytecode to check for
// finalizer registration so create a normal frame.
return zerolocals;
}
// Empty method?
if (m->is_empty_method()) {
return empty;
}
// Special intrinsic method?
// Note: This test must come _after_ the test for native methods,
// otherwise we will run into problems with JDK 1.2, see also
// InterpreterGenerator::generate_method_entry() for
// for details.
switch (m->intrinsic_id()) {
case vmIntrinsics::_dsin : return java_lang_math_sin ;
case vmIntrinsics::_dcos : return java_lang_math_cos ;
case vmIntrinsics::_dtan : return java_lang_math_tan ;
case vmIntrinsics::_dabs : return java_lang_math_abs ;
case vmIntrinsics::_dsqrt : return java_lang_math_sqrt ;
case vmIntrinsics::_dlog : return java_lang_math_log ;
case vmIntrinsics::_dlog10: return java_lang_math_log10;
case vmIntrinsics::_dpow : return java_lang_math_pow ;
case vmIntrinsics::_dexp : return java_lang_math_exp ;
case vmIntrinsics::_Reference_get:
return java_lang_ref_reference_get;
}
// Accessor method?
if (m->is_accessor()) {
assert(m->size_of_parameters() == 1, "fast code for accessors assumes parameter size = 1");
return accessor;
}
// Note: for now: zero locals for all non-empty methods
return zerolocals;
}