methodDataOop.cpp revision 2027
/*
* Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "classfile/systemDictionary.hpp"
#include "gc_implementation/shared/markSweep.inline.hpp"
#include "interpreter/bytecode.hpp"
#include "interpreter/bytecodeStream.hpp"
#include "interpreter/linkResolver.hpp"
#include "oops/methodDataOop.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/compilationPolicy.hpp"
#include "runtime/deoptimization.hpp"
#include "runtime/handles.inline.hpp"
// ==================================================================
// DataLayout
//
// Overlay for generic profiling data.
// Some types of data layouts need a length field.
bool DataLayout::needs_array_len(u1 tag) {
return (tag == multi_branch_data_tag) || (tag == arg_info_data_tag);
}
// Perform generic initialization of the data. More specific
// initialization occurs in overrides of ProfileData::post_initialize.
void DataLayout::initialize(u1 tag, u2 bci, int cell_count) {
_header._bits = (intptr_t)0;
_header._struct._tag = tag;
_header._struct._bci = bci;
for (int i = 0; i < cell_count; i++) {
set_cell_at(i, (intptr_t)0);
}
if (needs_array_len(tag)) {
set_cell_at(ArrayData::array_len_off_set, cell_count - 1); // -1 for header.
}
}
void DataLayout::follow_weak_refs(BoolObjectClosure* cl) {
ResourceMark m;
data_in()->follow_weak_refs(cl);
}
// ==================================================================
// ProfileData
//
// A ProfileData object is created to refer to a section of profiling
// data in a structured way.
// Constructor for invalid ProfileData.
ProfileData::ProfileData() {
_data = NULL;
}
#ifndef PRODUCT
void ProfileData::print_shared(outputStream* st, const char* name) {
st->print("bci: %d", bci());
st->fill_to(tab_width_one);
st->print("%s", name);
tab(st);
int trap = trap_state();
if (trap != 0) {
char buf[100];
st->print("trap(%s) ", Deoptimization::format_trap_state(buf, sizeof(buf), trap));
}
int flags = data()->flags();
if (flags != 0)
st->print("flags(%d) ", flags);
}
void ProfileData::tab(outputStream* st) {
st->fill_to(tab_width_two);
}
#endif // !PRODUCT
// ==================================================================
// BitData
//
// A BitData corresponds to a one-bit flag. This is used to indicate
// whether a checkcast bytecode has seen a null value.
#ifndef PRODUCT
void BitData::print_data_on(outputStream* st) {
print_shared(st, "BitData");
}
#endif // !PRODUCT
// ==================================================================
// CounterData
//
// A CounterData corresponds to a simple counter.
#ifndef PRODUCT
void CounterData::print_data_on(outputStream* st) {
print_shared(st, "CounterData");
st->print_cr("count(%u)", count());
}
#endif // !PRODUCT
// ==================================================================
// JumpData
//
// A JumpData is used to access profiling information for a direct
// branch. It is a counter, used for counting the number of branches,
// plus a data displacement, used for realigning the data pointer to
// the corresponding target bci.
void JumpData::post_initialize(BytecodeStream* stream, methodDataOop mdo) {
assert(stream->bci() == bci(), "wrong pos");
int target;
Bytecodes::Code c = stream->code();
if (c == Bytecodes::_goto_w || c == Bytecodes::_jsr_w) {
target = stream->dest_w();
} else {
target = stream->dest();
}
int my_di = mdo->dp_to_di(dp());
int target_di = mdo->bci_to_di(target);
int offset = target_di - my_di;
set_displacement(offset);
}
#ifndef PRODUCT
void JumpData::print_data_on(outputStream* st) {
print_shared(st, "JumpData");
st->print_cr("taken(%u) displacement(%d)", taken(), displacement());
}
#endif // !PRODUCT
// ==================================================================
// ReceiverTypeData
//
// A ReceiverTypeData is used to access profiling information about a
// dynamic type check. It consists of a counter which counts the total times
// that the check is reached, and a series of (klassOop, count) pairs
// which are used to store a type profile for the receiver of the check.
void ReceiverTypeData::follow_contents() {
// This is a set of weak references that need
// to be followed at the end of the strong marking
// phase. Memoize this object so it can be visited
// in the weak roots processing phase.
MarkSweep::revisit_mdo(data());
}
#ifndef SERIALGC
void ReceiverTypeData::follow_contents(ParCompactionManager* cm) {
// This is a set of weak references that need
// to be followed at the end of the strong marking
// phase. Memoize this object so it can be visited
// in the weak roots processing phase.
PSParallelCompact::revisit_mdo(cm, data());
}
#endif // SERIALGC
void ReceiverTypeData::oop_iterate(OopClosure* blk) {
if (blk->should_remember_mdo()) {
// This is a set of weak references that need
// to be followed at the end of the strong marking
// phase. Memoize this object so it can be visited
// in the weak roots processing phase.
blk->remember_mdo(data());
} else { // normal scan
for (uint row = 0; row < row_limit(); row++) {
if (receiver(row) != NULL) {
oop* adr = adr_receiver(row);
blk->do_oop(adr);
}
}
}
}
void ReceiverTypeData::oop_iterate_m(OopClosure* blk, MemRegion mr) {
// Currently, this interface is called only during card-scanning for
// a young gen gc, in which case this object cannot contribute anything,
// since it does not contain any references that cross out of
// the perm gen. However, for future more general use we allow
// the possibility of calling for instance from more general
// iterators (for example, a future regionalized perm gen for G1,
// or the possibility of moving some references out of perm in
// the case of other collectors). In that case, you will need
// to relax or remove some of the assertions below.
#ifdef ASSERT
// Verify that none of the embedded oop references cross out of
// this generation.
for (uint row = 0; row < row_limit(); row++) {
if (receiver(row) != NULL) {
oop* adr = adr_receiver(row);
CollectedHeap* h = Universe::heap();
assert(h->is_permanent(adr) && h->is_permanent_or_null(*adr), "Not intra-perm");
}
}
#endif // ASSERT
assert(!blk->should_remember_mdo(), "Not expected to remember MDO");
return; // Nothing to do, see comment above
#if 0
if (blk->should_remember_mdo()) {
// This is a set of weak references that need
// to be followed at the end of the strong marking
// phase. Memoize this object so it can be visited
// in the weak roots processing phase.
blk->remember_mdo(data());
} else { // normal scan
for (uint row = 0; row < row_limit(); row++) {
if (receiver(row) != NULL) {
oop* adr = adr_receiver(row);
if (mr.contains(adr)) {
blk->do_oop(adr);
} else if ((HeapWord*)adr >= mr.end()) {
// Test that the current cursor and the two ends of the range
// that we may have skipped iterating over are monotonically ordered;
// this is just a paranoid assertion, just in case represetations
// should change in the future rendering the short-circuit return
// here invalid.
assert((row+1 >= row_limit() || adr_receiver(row+1) > adr) &&
(row+2 >= row_limit() || adr_receiver(row_limit()-1) > adr_receiver(row+1)), "Reducing?");
break; // remaining should be outside this mr too
}
}
}
}
#endif
}
void ReceiverTypeData::adjust_pointers() {
for (uint row = 0; row < row_limit(); row++) {
if (receiver(row) != NULL) {
MarkSweep::adjust_pointer(adr_receiver(row));
}
}
}
void ReceiverTypeData::follow_weak_refs(BoolObjectClosure* is_alive_cl) {
for (uint row = 0; row < row_limit(); row++) {
klassOop p = receiver(row);
if (p != NULL && !is_alive_cl->do_object_b(p)) {
clear_row(row);
}
}
}
#ifndef SERIALGC
void ReceiverTypeData::update_pointers() {
for (uint row = 0; row < row_limit(); row++) {
if (receiver_unchecked(row) != NULL) {
PSParallelCompact::adjust_pointer(adr_receiver(row));
}
}
}
void ReceiverTypeData::update_pointers(HeapWord* beg_addr, HeapWord* end_addr) {
// The loop bounds could be computed based on beg_addr/end_addr and the
// boundary test hoisted outside the loop (see klassVTable for an example);
// however, row_limit() is small enough (2) to make that less efficient.
for (uint row = 0; row < row_limit(); row++) {
if (receiver_unchecked(row) != NULL) {
PSParallelCompact::adjust_pointer(adr_receiver(row), beg_addr, end_addr);
}
}
}
#endif // SERIALGC
#ifndef PRODUCT
void ReceiverTypeData::print_receiver_data_on(outputStream* st) {
uint row;
int entries = 0;
for (row = 0; row < row_limit(); row++) {
if (receiver(row) != NULL) entries++;
}
st->print_cr("count(%u) entries(%u)", count(), entries);
int total = count();
for (row = 0; row < row_limit(); row++) {
if (receiver(row) != NULL) {
total += receiver_count(row);
}
}
for (row = 0; row < row_limit(); row++) {
if (receiver(row) != NULL) {
tab(st);
receiver(row)->print_value_on(st);
st->print_cr("(%u %4.2f)", receiver_count(row), (float) receiver_count(row) / (float) total);
}
}
}
void ReceiverTypeData::print_data_on(outputStream* st) {
print_shared(st, "ReceiverTypeData");
print_receiver_data_on(st);
}
void VirtualCallData::print_data_on(outputStream* st) {
print_shared(st, "VirtualCallData");
print_receiver_data_on(st);
}
#endif // !PRODUCT
// ==================================================================
// RetData
//
// A RetData is used to access profiling information for a ret bytecode.
// It is composed of a count of the number of times that the ret has
// been executed, followed by a series of triples of the form
// (bci, count, di) which count the number of times that some bci was the
// target of the ret and cache a corresponding displacement.
void RetData::post_initialize(BytecodeStream* stream, methodDataOop mdo) {
for (uint row = 0; row < row_limit(); row++) {
set_bci_displacement(row, -1);
set_bci(row, no_bci);
}
// release so other threads see a consistent state. bci is used as
// a valid flag for bci_displacement.
OrderAccess::release();
}
// This routine needs to atomically update the RetData structure, so the
// caller needs to hold the RetData_lock before it gets here. Since taking
// the lock can block (and allow GC) and since RetData is a ProfileData is a
// wrapper around a derived oop, taking the lock in _this_ method will
// basically cause the 'this' pointer's _data field to contain junk after the
// lock. We require the caller to take the lock before making the ProfileData
// structure. Currently the only caller is InterpreterRuntime::update_mdp_for_ret
address RetData::fixup_ret(int return_bci, methodDataHandle h_mdo) {
// First find the mdp which corresponds to the return bci.
address mdp = h_mdo->bci_to_dp(return_bci);
// Now check to see if any of the cache slots are open.
for (uint row = 0; row < row_limit(); row++) {
if (bci(row) == no_bci) {
set_bci_displacement(row, mdp - dp());
set_bci_count(row, DataLayout::counter_increment);
// Barrier to ensure displacement is written before the bci; allows
// the interpreter to read displacement without fear of race condition.
release_set_bci(row, return_bci);
break;
}
}
return mdp;
}
#ifndef PRODUCT
void RetData::print_data_on(outputStream* st) {
print_shared(st, "RetData");
uint row;
int entries = 0;
for (row = 0; row < row_limit(); row++) {
if (bci(row) != no_bci) entries++;
}
st->print_cr("count(%u) entries(%u)", count(), entries);
for (row = 0; row < row_limit(); row++) {
if (bci(row) != no_bci) {
tab(st);
st->print_cr("bci(%d: count(%u) displacement(%d))",
bci(row), bci_count(row), bci_displacement(row));
}
}
}
#endif // !PRODUCT
// ==================================================================
// BranchData
//
// A BranchData is used to access profiling data for a two-way branch.
// It consists of taken and not_taken counts as well as a data displacement
// for the taken case.
void BranchData::post_initialize(BytecodeStream* stream, methodDataOop mdo) {
assert(stream->bci() == bci(), "wrong pos");
int target = stream->dest();
int my_di = mdo->dp_to_di(dp());
int target_di = mdo->bci_to_di(target);
int offset = target_di - my_di;
set_displacement(offset);
}
#ifndef PRODUCT
void BranchData::print_data_on(outputStream* st) {
print_shared(st, "BranchData");
st->print_cr("taken(%u) displacement(%d)",
taken(), displacement());
tab(st);
st->print_cr("not taken(%u)", not_taken());
}
#endif
// ==================================================================
// MultiBranchData
//
// A MultiBranchData is used to access profiling information for
// a multi-way branch (*switch bytecodes). It consists of a series
// of (count, displacement) pairs, which count the number of times each
// case was taken and specify the data displacment for each branch target.
int MultiBranchData::compute_cell_count(BytecodeStream* stream) {
int cell_count = 0;
if (stream->code() == Bytecodes::_tableswitch) {
Bytecode_tableswitch sw(stream->method()(), stream->bcp());
cell_count = 1 + per_case_cell_count * (1 + sw.length()); // 1 for default
} else {
Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
cell_count = 1 + per_case_cell_count * (sw.number_of_pairs() + 1); // 1 for default
}
return cell_count;
}
void MultiBranchData::post_initialize(BytecodeStream* stream,
methodDataOop mdo) {
assert(stream->bci() == bci(), "wrong pos");
int target;
int my_di;
int target_di;
int offset;
if (stream->code() == Bytecodes::_tableswitch) {
Bytecode_tableswitch sw(stream->method()(), stream->bcp());
int len = sw.length();
assert(array_len() == per_case_cell_count * (len + 1), "wrong len");
for (int count = 0; count < len; count++) {
target = sw.dest_offset_at(count) + bci();
my_di = mdo->dp_to_di(dp());
target_di = mdo->bci_to_di(target);
offset = target_di - my_di;
set_displacement_at(count, offset);
}
target = sw.default_offset() + bci();
my_di = mdo->dp_to_di(dp());
target_di = mdo->bci_to_di(target);
offset = target_di - my_di;
set_default_displacement(offset);
} else {
Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
int npairs = sw.number_of_pairs();
assert(array_len() == per_case_cell_count * (npairs + 1), "wrong len");
for (int count = 0; count < npairs; count++) {
LookupswitchPair pair = sw.pair_at(count);
target = pair.offset() + bci();
my_di = mdo->dp_to_di(dp());
target_di = mdo->bci_to_di(target);
offset = target_di - my_di;
set_displacement_at(count, offset);
}
target = sw.default_offset() + bci();
my_di = mdo->dp_to_di(dp());
target_di = mdo->bci_to_di(target);
offset = target_di - my_di;
set_default_displacement(offset);
}
}
#ifndef PRODUCT
void MultiBranchData::print_data_on(outputStream* st) {
print_shared(st, "MultiBranchData");
st->print_cr("default_count(%u) displacement(%d)",
default_count(), default_displacement());
int cases = number_of_cases();
for (int i = 0; i < cases; i++) {
tab(st);
st->print_cr("count(%u) displacement(%d)",
count_at(i), displacement_at(i));
}
}
#endif
#ifndef PRODUCT
void ArgInfoData::print_data_on(outputStream* st) {
print_shared(st, "ArgInfoData");
int nargs = number_of_args();
for (int i = 0; i < nargs; i++) {
st->print(" 0x%x", arg_modified(i));
}
st->cr();
}
#endif
// ==================================================================
// methodDataOop
//
// A methodDataOop holds information which has been collected about
// a method.
int methodDataOopDesc::bytecode_cell_count(Bytecodes::Code code) {
switch (code) {
case Bytecodes::_checkcast:
case Bytecodes::_instanceof:
case Bytecodes::_aastore:
if (TypeProfileCasts) {
return ReceiverTypeData::static_cell_count();
} else {
return BitData::static_cell_count();
}
case Bytecodes::_invokespecial:
case Bytecodes::_invokestatic:
return CounterData::static_cell_count();
case Bytecodes::_goto:
case Bytecodes::_goto_w:
case Bytecodes::_jsr:
case Bytecodes::_jsr_w:
return JumpData::static_cell_count();
case Bytecodes::_invokevirtual:
case Bytecodes::_invokeinterface:
return VirtualCallData::static_cell_count();
case Bytecodes::_invokedynamic:
return CounterData::static_cell_count();
case Bytecodes::_ret:
return RetData::static_cell_count();
case Bytecodes::_ifeq:
case Bytecodes::_ifne:
case Bytecodes::_iflt:
case Bytecodes::_ifge:
case Bytecodes::_ifgt:
case Bytecodes::_ifle:
case Bytecodes::_if_icmpeq:
case Bytecodes::_if_icmpne:
case Bytecodes::_if_icmplt:
case Bytecodes::_if_icmpge:
case Bytecodes::_if_icmpgt:
case Bytecodes::_if_icmple:
case Bytecodes::_if_acmpeq:
case Bytecodes::_if_acmpne:
case Bytecodes::_ifnull:
case Bytecodes::_ifnonnull:
return BranchData::static_cell_count();
case Bytecodes::_lookupswitch:
case Bytecodes::_tableswitch:
return variable_cell_count;
}
return no_profile_data;
}
// Compute the size of the profiling information corresponding to
// the current bytecode.
int methodDataOopDesc::compute_data_size(BytecodeStream* stream) {
int cell_count = bytecode_cell_count(stream->code());
if (cell_count == no_profile_data) {
return 0;
}
if (cell_count == variable_cell_count) {
cell_count = MultiBranchData::compute_cell_count(stream);
}
// Note: cell_count might be zero, meaning that there is just
// a DataLayout header, with no extra cells.
assert(cell_count >= 0, "sanity");
return DataLayout::compute_size_in_bytes(cell_count);
}
int methodDataOopDesc::compute_extra_data_count(int data_size, int empty_bc_count) {
if (ProfileTraps) {
// Assume that up to 3% of BCIs with no MDP will need to allocate one.
int extra_data_count = (uint)(empty_bc_count * 3) / 128 + 1;
// If the method is large, let the extra BCIs grow numerous (to ~1%).
int one_percent_of_data
= (uint)data_size / (DataLayout::header_size_in_bytes()*128);
if (extra_data_count < one_percent_of_data)
extra_data_count = one_percent_of_data;
if (extra_data_count > empty_bc_count)
extra_data_count = empty_bc_count; // no need for more
return extra_data_count;
} else {
return 0;
}
}
// 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;
}
// Compute the size of the methodDataOop necessary to store
// profiling information about a given method. Size is in words
int methodDataOopDesc::compute_allocation_size_in_words(methodHandle method) {
int byte_size = compute_allocation_size_in_bytes(method);
int word_size = align_size_up(byte_size, BytesPerWord) / BytesPerWord;
return align_object_size(word_size);
}
// Initialize an individual data segment. Returns the size of
// the segment in bytes.
int methodDataOopDesc::initialize_data(BytecodeStream* stream,
int data_index) {
int cell_count = -1;
int tag = DataLayout::no_tag;
DataLayout* data_layout = data_layout_at(data_index);
Bytecodes::Code c = stream->code();
switch (c) {
case Bytecodes::_checkcast:
case Bytecodes::_instanceof:
case Bytecodes::_aastore:
if (TypeProfileCasts) {
cell_count = ReceiverTypeData::static_cell_count();
tag = DataLayout::receiver_type_data_tag;
} else {
cell_count = BitData::static_cell_count();
tag = DataLayout::bit_data_tag;
}
break;
case Bytecodes::_invokespecial:
case Bytecodes::_invokestatic:
cell_count = CounterData::static_cell_count();
tag = DataLayout::counter_data_tag;
break;
case Bytecodes::_goto:
case Bytecodes::_goto_w:
case Bytecodes::_jsr:
case Bytecodes::_jsr_w:
cell_count = JumpData::static_cell_count();
tag = DataLayout::jump_data_tag;
break;
case Bytecodes::_invokevirtual:
case Bytecodes::_invokeinterface:
cell_count = VirtualCallData::static_cell_count();
tag = DataLayout::virtual_call_data_tag;
break;
case Bytecodes::_invokedynamic:
// %%% should make a type profile for any invokedynamic that takes a ref argument
cell_count = CounterData::static_cell_count();
tag = DataLayout::counter_data_tag;
break;
case Bytecodes::_ret:
cell_count = RetData::static_cell_count();
tag = DataLayout::ret_data_tag;
break;
case Bytecodes::_ifeq:
case Bytecodes::_ifne:
case Bytecodes::_iflt:
case Bytecodes::_ifge:
case Bytecodes::_ifgt:
case Bytecodes::_ifle:
case Bytecodes::_if_icmpeq:
case Bytecodes::_if_icmpne:
case Bytecodes::_if_icmplt:
case Bytecodes::_if_icmpge:
case Bytecodes::_if_icmpgt:
case Bytecodes::_if_icmple:
case Bytecodes::_if_acmpeq:
case Bytecodes::_if_acmpne:
case Bytecodes::_ifnull:
case Bytecodes::_ifnonnull:
cell_count = BranchData::static_cell_count();
tag = DataLayout::branch_data_tag;
break;
case Bytecodes::_lookupswitch:
case Bytecodes::_tableswitch:
cell_count = MultiBranchData::compute_cell_count(stream);
tag = DataLayout::multi_branch_data_tag;
break;
}
assert(tag == DataLayout::multi_branch_data_tag ||
cell_count == bytecode_cell_count(c), "cell counts must agree");
if (cell_count >= 0) {
assert(tag != DataLayout::no_tag, "bad tag");
assert(bytecode_has_profile(c), "agree w/ BHP");
data_layout->initialize(tag, stream->bci(), cell_count);
return DataLayout::compute_size_in_bytes(cell_count);
} else {
assert(!bytecode_has_profile(c), "agree w/ !BHP");
return 0;
}
}
// Get the data at an arbitrary (sort of) data index.
ProfileData* methodDataOopDesc::data_at(int data_index) {
if (out_of_bounds(data_index)) {
return NULL;
}
DataLayout* data_layout = data_layout_at(data_index);
return data_layout->data_in();
}
ProfileData* DataLayout::data_in() {
switch (tag()) {
case DataLayout::no_tag:
default:
ShouldNotReachHere();
return NULL;
case DataLayout::bit_data_tag:
return new BitData(this);
case DataLayout::counter_data_tag:
return new CounterData(this);
case DataLayout::jump_data_tag:
return new JumpData(this);
case DataLayout::receiver_type_data_tag:
return new ReceiverTypeData(this);
case DataLayout::virtual_call_data_tag:
return new VirtualCallData(this);
case DataLayout::ret_data_tag:
return new RetData(this);
case DataLayout::branch_data_tag:
return new BranchData(this);
case DataLayout::multi_branch_data_tag:
return new MultiBranchData(this);
case DataLayout::arg_info_data_tag:
return new ArgInfoData(this);
};
}
// Iteration over data.
ProfileData* methodDataOopDesc::next_data(ProfileData* current) {
int current_index = dp_to_di(current->dp());
int next_index = current_index + current->size_in_bytes();
ProfileData* next = data_at(next_index);
return next;
}
// Give each of the data entries a chance to perform specific
// data initialization.
void methodDataOopDesc::post_initialize(BytecodeStream* stream) {
ResourceMark rm;
ProfileData* data;
for (data = first_data(); is_valid(data); data = next_data(data)) {
stream->set_start(data->bci());
stream->next();
data->post_initialize(stream, this);
}
}
// Initialize the methodDataOop corresponding to a given method.
void methodDataOopDesc::initialize(methodHandle method) {
ResourceMark rm;
// Set the method back-pointer.
_method = method();
if (TieredCompilation) {
_invocation_counter.init();
_backedge_counter.init();
_num_loops = 0;
_num_blocks = 0;
_highest_comp_level = 0;
_highest_osr_comp_level = 0;
_would_profile = false;
}
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);
}
// Get a measure of how much mileage the method has on it.
int methodDataOopDesc::mileage_of(methodOop method) {
int mileage = 0;
if (TieredCompilation) {
mileage = MAX2(method->invocation_count(), method->backedge_count());
} else {
int iic = method->interpreter_invocation_count();
if (mileage < iic) mileage = iic;
InvocationCounter* ic = method->invocation_counter();
InvocationCounter* bc = method->backedge_counter();
int icval = ic->count();
if (ic->carry()) icval += CompileThreshold;
if (mileage < icval) mileage = icval;
int bcval = bc->count();
if (bc->carry()) bcval += CompileThreshold;
if (mileage < bcval) mileage = bcval;
}
return mileage;
}
bool methodDataOopDesc::is_mature() const {
return CompilationPolicy::policy()->is_mature(_method);
}
// Translate a bci to its corresponding data index (di).
address methodDataOopDesc::bci_to_dp(int bci) {
ResourceMark rm;
ProfileData* data = data_before(bci);
ProfileData* prev = NULL;
for ( ; is_valid(data); data = next_data(data)) {
if (data->bci() >= bci) {
if (data->bci() == bci) set_hint_di(dp_to_di(data->dp()));
else if (prev != NULL) set_hint_di(dp_to_di(prev->dp()));
return data->dp();
}
prev = data;
}
return (address)limit_data_position();
}
// Translate a bci to its corresponding data, or NULL.
ProfileData* methodDataOopDesc::bci_to_data(int bci) {
ProfileData* data = data_before(bci);
for ( ; is_valid(data); data = next_data(data)) {
if (data->bci() == bci) {
set_hint_di(dp_to_di(data->dp()));
return data;
} else if (data->bci() > bci) {
break;
}
}
return bci_to_extra_data(bci, false);
}
// Translate a bci to its corresponding extra data, or NULL.
ProfileData* methodDataOopDesc::bci_to_extra_data(int bci, bool create_if_missing) {
DataLayout* dp = extra_data_base();
DataLayout* end = extra_data_limit();
DataLayout* avail = NULL;
for (; dp < end; dp = next_extra(dp)) {
// No need for "OrderAccess::load_acquire" ops,
// since the data structure is monotonic.
if (dp->tag() == DataLayout::no_tag) break;
if (dp->tag() == DataLayout::arg_info_data_tag) {
dp = end; // ArgInfoData is at the end of extra data section.
break;
}
if (dp->bci() == bci) {
assert(dp->tag() == DataLayout::bit_data_tag, "sane");
return new BitData(dp);
}
}
if (create_if_missing && dp < end) {
// Allocate this one. There is no mutual exclusion,
// so two threads could allocate different BCIs to the
// same data layout. This means these extra data
// records, like most other MDO contents, must not be
// trusted too much.
DataLayout temp;
temp.initialize(DataLayout::bit_data_tag, bci, 0);
dp->release_set_header(temp.header());
assert(dp->tag() == DataLayout::bit_data_tag, "sane");
//NO: assert(dp->bci() == bci, "no concurrent allocation");
return new BitData(dp);
}
return NULL;
}
ArgInfoData *methodDataOopDesc::arg_info() {
DataLayout* dp = extra_data_base();
DataLayout* end = extra_data_limit();
for (; dp < end; dp = next_extra(dp)) {
if (dp->tag() == DataLayout::arg_info_data_tag)
return new ArgInfoData(dp);
}
return NULL;
}
#ifndef PRODUCT
void methodDataOopDesc::print_data_on(outputStream* st) {
ResourceMark rm;
ProfileData* data = first_data();
for ( ; is_valid(data); data = next_data(data)) {
st->print("%d", dp_to_di(data->dp()));
st->fill_to(6);
data->print_data_on(st);
}
st->print_cr("--- Extra data:");
DataLayout* dp = extra_data_base();
DataLayout* end = extra_data_limit();
for (; dp < end; dp = next_extra(dp)) {
// No need for "OrderAccess::load_acquire" ops,
// since the data structure is monotonic.
if (dp->tag() == DataLayout::no_tag) continue;
if (dp->tag() == DataLayout::bit_data_tag) {
data = new BitData(dp);
} else {
assert(dp->tag() == DataLayout::arg_info_data_tag, "must be BitData or ArgInfo");
data = new ArgInfoData(dp);
dp = end; // ArgInfoData is at the end of extra data section.
}
st->print("%d", dp_to_di(data->dp()));
st->fill_to(6);
data->print_data_on(st);
}
}
#endif
void methodDataOopDesc::verify_data_on(outputStream* st) {
NEEDS_CLEANUP;
// not yet implemented.
}