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c1_GraphBuilder.cpp
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c1_GraphBuilder.cpp
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/*
* Copyright (c) 1999, 2021, 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 "c1/c1_CFGPrinter.hpp"
#include "c1/c1_Canonicalizer.hpp"
#include "c1/c1_Compilation.hpp"
#include "c1/c1_GraphBuilder.hpp"
#include "c1/c1_InstructionPrinter.hpp"
#include "ci/ciCallSite.hpp"
#include "ci/ciField.hpp"
#include "ci/ciFlatArrayKlass.hpp"
#include "ci/ciInlineKlass.hpp"
#include "ci/ciKlass.hpp"
#include "ci/ciMemberName.hpp"
#include "ci/ciSymbols.hpp"
#include "ci/ciUtilities.inline.hpp"
#include "compiler/compilationPolicy.hpp"
#include "compiler/compileBroker.hpp"
#include "compiler/compilerEvent.hpp"
#include "interpreter/bytecode.hpp"
#include "jfr/jfrEvents.hpp"
#include "memory/resourceArea.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/vm_version.hpp"
#include "utilities/bitMap.inline.hpp"
#include "utilities/powerOfTwo.hpp"
class BlockListBuilder {
private:
Compilation* _compilation;
IRScope* _scope;
BlockList _blocks; // internal list of all blocks
BlockList* _bci2block; // mapping from bci to blocks for GraphBuilder
// fields used by mark_loops
ResourceBitMap _active; // for iteration of control flow graph
ResourceBitMap _visited; // for iteration of control flow graph
intArray _loop_map; // caches the information if a block is contained in a loop
int _next_loop_index; // next free loop number
int _next_block_number; // for reverse postorder numbering of blocks
// accessors
Compilation* compilation() const { return _compilation; }
IRScope* scope() const { return _scope; }
ciMethod* method() const { return scope()->method(); }
XHandlers* xhandlers() const { return scope()->xhandlers(); }
// unified bailout support
void bailout(const char* msg) const { compilation()->bailout(msg); }
bool bailed_out() const { return compilation()->bailed_out(); }
// helper functions
BlockBegin* make_block_at(int bci, BlockBegin* predecessor);
void handle_exceptions(BlockBegin* current, int cur_bci);
void handle_jsr(BlockBegin* current, int sr_bci, int next_bci);
void store_one(BlockBegin* current, int local);
void store_two(BlockBegin* current, int local);
void set_entries(int osr_bci);
void set_leaders();
void make_loop_header(BlockBegin* block);
void mark_loops();
int mark_loops(BlockBegin* b, bool in_subroutine);
// debugging
#ifndef PRODUCT
void print();
#endif
public:
// creation
BlockListBuilder(Compilation* compilation, IRScope* scope, int osr_bci);
// accessors for GraphBuilder
BlockList* bci2block() const { return _bci2block; }
};
// Implementation of BlockListBuilder
BlockListBuilder::BlockListBuilder(Compilation* compilation, IRScope* scope, int osr_bci)
: _compilation(compilation)
, _scope(scope)
, _blocks(16)
, _bci2block(new BlockList(scope->method()->code_size(), NULL))
, _active() // size not known yet
, _visited() // size not known yet
, _loop_map() // size not known yet
, _next_loop_index(0)
, _next_block_number(0)
{
set_entries(osr_bci);
set_leaders();
CHECK_BAILOUT();
mark_loops();
NOT_PRODUCT(if (PrintInitialBlockList) print());
#ifndef PRODUCT
if (PrintCFGToFile) {
stringStream title;
title.print("BlockListBuilder ");
scope->method()->print_name(&title);
CFGPrinter::print_cfg(_bci2block, title.as_string(), false, false);
}
#endif
}
void BlockListBuilder::set_entries(int osr_bci) {
// generate start blocks
BlockBegin* std_entry = make_block_at(0, NULL);
if (scope()->caller() == NULL) {
std_entry->set(BlockBegin::std_entry_flag);
}
if (osr_bci != -1) {
BlockBegin* osr_entry = make_block_at(osr_bci, NULL);
osr_entry->set(BlockBegin::osr_entry_flag);
}
// generate exception entry blocks
XHandlers* list = xhandlers();
const int n = list->length();
for (int i = 0; i < n; i++) {
XHandler* h = list->handler_at(i);
BlockBegin* entry = make_block_at(h->handler_bci(), NULL);
entry->set(BlockBegin::exception_entry_flag);
h->set_entry_block(entry);
}
}
BlockBegin* BlockListBuilder::make_block_at(int cur_bci, BlockBegin* predecessor) {
assert(method()->bci_block_start().at(cur_bci), "wrong block starts of MethodLivenessAnalyzer");
BlockBegin* block = _bci2block->at(cur_bci);
if (block == NULL) {
block = new BlockBegin(cur_bci);
block->init_stores_to_locals(method()->max_locals());
_bci2block->at_put(cur_bci, block);
_blocks.append(block);
assert(predecessor == NULL || predecessor->bci() < cur_bci, "targets for backward branches must already exist");
}
if (predecessor != NULL) {
if (block->is_set(BlockBegin::exception_entry_flag)) {
BAILOUT_("Exception handler can be reached by both normal and exceptional control flow", block);
}
predecessor->add_successor(block);
block->increment_total_preds();
}
return block;
}
inline void BlockListBuilder::store_one(BlockBegin* current, int local) {
current->stores_to_locals().set_bit(local);
}
inline void BlockListBuilder::store_two(BlockBegin* current, int local) {
store_one(current, local);
store_one(current, local + 1);
}
void BlockListBuilder::handle_exceptions(BlockBegin* current, int cur_bci) {
// Draws edges from a block to its exception handlers
XHandlers* list = xhandlers();
const int n = list->length();
for (int i = 0; i < n; i++) {
XHandler* h = list->handler_at(i);
if (h->covers(cur_bci)) {
BlockBegin* entry = h->entry_block();
assert(entry != NULL && entry == _bci2block->at(h->handler_bci()), "entry must be set");
assert(entry->is_set(BlockBegin::exception_entry_flag), "flag must be set");
// add each exception handler only once
if (!current->is_successor(entry)) {
current->add_successor(entry);
entry->increment_total_preds();
}
// stop when reaching catchall
if (h->catch_type() == 0) break;
}
}
}
void BlockListBuilder::handle_jsr(BlockBegin* current, int sr_bci, int next_bci) {
// start a new block after jsr-bytecode and link this block into cfg
make_block_at(next_bci, current);
// start a new block at the subroutine entry at mark it with special flag
BlockBegin* sr_block = make_block_at(sr_bci, current);
if (!sr_block->is_set(BlockBegin::subroutine_entry_flag)) {
sr_block->set(BlockBegin::subroutine_entry_flag);
}
}
void BlockListBuilder::set_leaders() {
bool has_xhandlers = xhandlers()->has_handlers();
BlockBegin* current = NULL;
// The information which bci starts a new block simplifies the analysis
// Without it, backward branches could jump to a bci where no block was created
// during bytecode iteration. This would require the creation of a new block at the
// branch target and a modification of the successor lists.
const BitMap& bci_block_start = method()->bci_block_start();
ciBytecodeStream s(method());
while (s.next() != ciBytecodeStream::EOBC()) {
int cur_bci = s.cur_bci();
if (bci_block_start.at(cur_bci)) {
current = make_block_at(cur_bci, current);
}
assert(current != NULL, "must have current block");
if (has_xhandlers && GraphBuilder::can_trap(method(), s.cur_bc())) {
handle_exceptions(current, cur_bci);
}
switch (s.cur_bc()) {
// track stores to local variables for selective creation of phi functions
case Bytecodes::_iinc: store_one(current, s.get_index()); break;
case Bytecodes::_istore: store_one(current, s.get_index()); break;
case Bytecodes::_lstore: store_two(current, s.get_index()); break;
case Bytecodes::_fstore: store_one(current, s.get_index()); break;
case Bytecodes::_dstore: store_two(current, s.get_index()); break;
case Bytecodes::_astore: store_one(current, s.get_index()); break;
case Bytecodes::_istore_0: store_one(current, 0); break;
case Bytecodes::_istore_1: store_one(current, 1); break;
case Bytecodes::_istore_2: store_one(current, 2); break;
case Bytecodes::_istore_3: store_one(current, 3); break;
case Bytecodes::_lstore_0: store_two(current, 0); break;
case Bytecodes::_lstore_1: store_two(current, 1); break;
case Bytecodes::_lstore_2: store_two(current, 2); break;
case Bytecodes::_lstore_3: store_two(current, 3); break;
case Bytecodes::_fstore_0: store_one(current, 0); break;
case Bytecodes::_fstore_1: store_one(current, 1); break;
case Bytecodes::_fstore_2: store_one(current, 2); break;
case Bytecodes::_fstore_3: store_one(current, 3); break;
case Bytecodes::_dstore_0: store_two(current, 0); break;
case Bytecodes::_dstore_1: store_two(current, 1); break;
case Bytecodes::_dstore_2: store_two(current, 2); break;
case Bytecodes::_dstore_3: store_two(current, 3); break;
case Bytecodes::_astore_0: store_one(current, 0); break;
case Bytecodes::_astore_1: store_one(current, 1); break;
case Bytecodes::_astore_2: store_one(current, 2); break;
case Bytecodes::_astore_3: store_one(current, 3); break;
// track bytecodes that affect the control flow
case Bytecodes::_athrow: // fall through
case Bytecodes::_ret: // fall through
case Bytecodes::_ireturn: // fall through
case Bytecodes::_lreturn: // fall through
case Bytecodes::_freturn: // fall through
case Bytecodes::_dreturn: // fall through
case Bytecodes::_areturn: // fall through
case Bytecodes::_return:
current = NULL;
break;
case Bytecodes::_ifeq: // fall through
case Bytecodes::_ifne: // fall through
case Bytecodes::_iflt: // fall through
case Bytecodes::_ifge: // fall through
case Bytecodes::_ifgt: // fall through
case Bytecodes::_ifle: // fall through
case Bytecodes::_if_icmpeq: // fall through
case Bytecodes::_if_icmpne: // fall through
case Bytecodes::_if_icmplt: // fall through
case Bytecodes::_if_icmpge: // fall through
case Bytecodes::_if_icmpgt: // fall through
case Bytecodes::_if_icmple: // fall through
case Bytecodes::_if_acmpeq: // fall through
case Bytecodes::_if_acmpne: // fall through
case Bytecodes::_ifnull: // fall through
case Bytecodes::_ifnonnull:
make_block_at(s.next_bci(), current);
make_block_at(s.get_dest(), current);
current = NULL;
break;
case Bytecodes::_goto:
make_block_at(s.get_dest(), current);
current = NULL;
break;
case Bytecodes::_goto_w:
make_block_at(s.get_far_dest(), current);
current = NULL;
break;
case Bytecodes::_jsr:
handle_jsr(current, s.get_dest(), s.next_bci());
current = NULL;
break;
case Bytecodes::_jsr_w:
handle_jsr(current, s.get_far_dest(), s.next_bci());
current = NULL;
break;
case Bytecodes::_tableswitch: {
// set block for each case
Bytecode_tableswitch sw(&s);
int l = sw.length();
for (int i = 0; i < l; i++) {
make_block_at(cur_bci + sw.dest_offset_at(i), current);
}
make_block_at(cur_bci + sw.default_offset(), current);
current = NULL;
break;
}
case Bytecodes::_lookupswitch: {
// set block for each case
Bytecode_lookupswitch sw(&s);
int l = sw.number_of_pairs();
for (int i = 0; i < l; i++) {
make_block_at(cur_bci + sw.pair_at(i).offset(), current);
}
make_block_at(cur_bci + sw.default_offset(), current);
current = NULL;
break;
}
default:
break;
}
}
}
void BlockListBuilder::mark_loops() {
ResourceMark rm;
_active.initialize(BlockBegin::number_of_blocks());
_visited.initialize(BlockBegin::number_of_blocks());
_loop_map = intArray(BlockBegin::number_of_blocks(), BlockBegin::number_of_blocks(), 0);
_next_loop_index = 0;
_next_block_number = _blocks.length();
// recursively iterate the control flow graph
mark_loops(_bci2block->at(0), false);
assert(_next_block_number >= 0, "invalid block numbers");
// Remove dangling Resource pointers before the ResourceMark goes out-of-scope.
_active.resize(0);
_visited.resize(0);
}
void BlockListBuilder::make_loop_header(BlockBegin* block) {
if (block->is_set(BlockBegin::exception_entry_flag)) {
// exception edges may look like loops but don't mark them as such
// since it screws up block ordering.
return;
}
if (!block->is_set(BlockBegin::parser_loop_header_flag)) {
block->set(BlockBegin::parser_loop_header_flag);
assert(_loop_map.at(block->block_id()) == 0, "must not be set yet");
assert(0 <= _next_loop_index && _next_loop_index < BitsPerInt, "_next_loop_index is used as a bit-index in integer");
_loop_map.at_put(block->block_id(), 1 << _next_loop_index);
if (_next_loop_index < 31) _next_loop_index++;
} else {
// block already marked as loop header
assert(is_power_of_2((unsigned int)_loop_map.at(block->block_id())), "exactly one bit must be set");
}
}
int BlockListBuilder::mark_loops(BlockBegin* block, bool in_subroutine) {
int block_id = block->block_id();
if (_visited.at(block_id)) {
if (_active.at(block_id)) {
// reached block via backward branch
make_loop_header(block);
}
// return cached loop information for this block
return _loop_map.at(block_id);
}
if (block->is_set(BlockBegin::subroutine_entry_flag)) {
in_subroutine = true;
}
// set active and visited bits before successors are processed
_visited.set_bit(block_id);
_active.set_bit(block_id);
intptr_t loop_state = 0;
for (int i = block->number_of_sux() - 1; i >= 0; i--) {
// recursively process all successors
loop_state |= mark_loops(block->sux_at(i), in_subroutine);
}
// clear active-bit after all successors are processed
_active.clear_bit(block_id);
// reverse-post-order numbering of all blocks
block->set_depth_first_number(_next_block_number);
_next_block_number--;
if (loop_state != 0 || in_subroutine ) {
// block is contained at least in one loop, so phi functions are necessary
// phi functions are also necessary for all locals stored in a subroutine
scope()->requires_phi_function().set_union(block->stores_to_locals());
}
if (block->is_set(BlockBegin::parser_loop_header_flag)) {
int header_loop_state = _loop_map.at(block_id);
assert(is_power_of_2((unsigned)header_loop_state), "exactly one bit must be set");
// If the highest bit is set (i.e. when integer value is negative), the method
// has 32 or more loops. This bit is never cleared because it is used for multiple loops
if (header_loop_state >= 0) {
clear_bits(loop_state, header_loop_state);
}
}
// cache and return loop information for this block
_loop_map.at_put(block_id, loop_state);
return loop_state;
}
#ifndef PRODUCT
int compare_depth_first(BlockBegin** a, BlockBegin** b) {
return (*a)->depth_first_number() - (*b)->depth_first_number();
}
void BlockListBuilder::print() {
tty->print("----- initial block list of BlockListBuilder for method ");
method()->print_short_name();
tty->cr();
// better readability if blocks are sorted in processing order
_blocks.sort(compare_depth_first);
for (int i = 0; i < _blocks.length(); i++) {
BlockBegin* cur = _blocks.at(i);
tty->print("%4d: B%-4d bci: %-4d preds: %-4d ", cur->depth_first_number(), cur->block_id(), cur->bci(), cur->total_preds());
tty->print(cur->is_set(BlockBegin::std_entry_flag) ? " std" : " ");
tty->print(cur->is_set(BlockBegin::osr_entry_flag) ? " osr" : " ");
tty->print(cur->is_set(BlockBegin::exception_entry_flag) ? " ex" : " ");
tty->print(cur->is_set(BlockBegin::subroutine_entry_flag) ? " sr" : " ");
tty->print(cur->is_set(BlockBegin::parser_loop_header_flag) ? " lh" : " ");
if (cur->number_of_sux() > 0) {
tty->print(" sux: ");
for (int j = 0; j < cur->number_of_sux(); j++) {
BlockBegin* sux = cur->sux_at(j);
tty->print("B%d ", sux->block_id());
}
}
tty->cr();
}
}
#endif
// A simple growable array of Values indexed by ciFields
class FieldBuffer: public CompilationResourceObj {
private:
GrowableArray<Value> _values;
public:
FieldBuffer() {}
void kill() {
_values.trunc_to(0);
}
Value at(ciField* field) {
assert(field->holder()->is_loaded(), "must be a loaded field");
int offset = field->offset();
if (offset < _values.length()) {
return _values.at(offset);
} else {
return NULL;
}
}
void at_put(ciField* field, Value value) {
assert(field->holder()->is_loaded(), "must be a loaded field");
int offset = field->offset();
_values.at_put_grow(offset, value, NULL);
}
};
// MemoryBuffer is fairly simple model of the current state of memory.
// It partitions memory into several pieces. The first piece is
// generic memory where little is known about the owner of the memory.
// This is conceptually represented by the tuple <O, F, V> which says
// that the field F of object O has value V. This is flattened so
// that F is represented by the offset of the field and the parallel
// arrays _objects and _values are used for O and V. Loads of O.F can
// simply use V. Newly allocated objects are kept in a separate list
// along with a parallel array for each object which represents the
// current value of its fields. Stores of the default value to fields
// which have never been stored to before are eliminated since they
// are redundant. Once newly allocated objects are stored into
// another object or they are passed out of the current compile they
// are treated like generic memory.
class MemoryBuffer: public CompilationResourceObj {
private:
FieldBuffer _values;
GrowableArray<Value> _objects;
GrowableArray<Value> _newobjects;
GrowableArray<FieldBuffer*> _fields;
public:
MemoryBuffer() {}
StoreField* store(StoreField* st) {
if (!EliminateFieldAccess) {
return st;
}
Value object = st->obj();
Value value = st->value();
ciField* field = st->field();
if (field->holder()->is_loaded()) {
int offset = field->offset();
int index = _newobjects.find(object);
if (index != -1) {
// newly allocated object with no other stores performed on this field
FieldBuffer* buf = _fields.at(index);
if (buf->at(field) == NULL && is_default_value(value)) {
#ifndef PRODUCT
if (PrintIRDuringConstruction && Verbose) {
tty->print_cr("Eliminated store for object %d:", index);
st->print_line();
}
#endif
return NULL;
} else {
buf->at_put(field, value);
}
} else {
_objects.at_put_grow(offset, object, NULL);
_values.at_put(field, value);
}
store_value(value);
} else {
// if we held onto field names we could alias based on names but
// we don't know what's being stored to so kill it all.
kill();
}
return st;
}
// return true if this value correspond to the default value of a field.
bool is_default_value(Value value) {
Constant* con = value->as_Constant();
if (con) {
switch (con->type()->tag()) {
case intTag: return con->type()->as_IntConstant()->value() == 0;
case longTag: return con->type()->as_LongConstant()->value() == 0;
case floatTag: return jint_cast(con->type()->as_FloatConstant()->value()) == 0;
case doubleTag: return jlong_cast(con->type()->as_DoubleConstant()->value()) == jlong_cast(0);
case objectTag: return con->type() == objectNull;
default: ShouldNotReachHere();
}
}
return false;
}
// return either the actual value of a load or the load itself
Value load(LoadField* load) {
if (!EliminateFieldAccess) {
return load;
}
if (strict_fp_requires_explicit_rounding && load->type()->is_float_kind()) {
#ifdef IA32
if (UseSSE < 2) {
// can't skip load since value might get rounded as a side effect
return load;
}
#else
Unimplemented();
#endif // IA32
}
ciField* field = load->field();
Value object = load->obj();
if (field->holder()->is_loaded() && !field->is_volatile()) {
int offset = field->offset();
Value result = NULL;
int index = _newobjects.find(object);
if (index != -1) {
result = _fields.at(index)->at(field);
} else if (_objects.at_grow(offset, NULL) == object) {
result = _values.at(field);
}
if (result != NULL) {
#ifndef PRODUCT
if (PrintIRDuringConstruction && Verbose) {
tty->print_cr("Eliminated load: ");
load->print_line();
}
#endif
assert(result->type()->tag() == load->type()->tag(), "wrong types");
return result;
}
}
return load;
}
// Record this newly allocated object
void new_instance(NewInstance* object) {
int index = _newobjects.length();
_newobjects.append(object);
if (_fields.at_grow(index, NULL) == NULL) {
_fields.at_put(index, new FieldBuffer());
} else {
_fields.at(index)->kill();
}
}
// Record this newly allocated object
void new_instance(NewInlineTypeInstance* object) {
int index = _newobjects.length();
_newobjects.append(object);
if (_fields.at_grow(index, NULL) == NULL) {
_fields.at_put(index, new FieldBuffer());
} else {
_fields.at(index)->kill();
}
}
void store_value(Value value) {
int index = _newobjects.find(value);
if (index != -1) {
// stored a newly allocated object into another object.
// Assume we've lost track of it as separate slice of memory.
// We could do better by keeping track of whether individual
// fields could alias each other.
_newobjects.remove_at(index);
// pull out the field info and store it at the end up the list
// of field info list to be reused later.
_fields.append(_fields.at(index));
_fields.remove_at(index);
}
}
void kill() {
_newobjects.trunc_to(0);
_objects.trunc_to(0);
_values.kill();
}
};
// Implementation of GraphBuilder's ScopeData
GraphBuilder::ScopeData::ScopeData(ScopeData* parent)
: _parent(parent)
, _bci2block(NULL)
, _scope(NULL)
, _has_handler(false)
, _stream(NULL)
, _work_list(NULL)
, _caller_stack_size(-1)
, _continuation(NULL)
, _parsing_jsr(false)
, _jsr_xhandlers(NULL)
, _num_returns(0)
, _cleanup_block(NULL)
, _cleanup_return_prev(NULL)
, _cleanup_state(NULL)
, _ignore_return(false)
{
if (parent != NULL) {
_max_inline_size = (intx) ((float) NestedInliningSizeRatio * (float) parent->max_inline_size() / 100.0f);
} else {
_max_inline_size = C1MaxInlineSize;
}
if (_max_inline_size < C1MaxTrivialSize) {
_max_inline_size = C1MaxTrivialSize;
}
}
void GraphBuilder::kill_all() {
if (UseLocalValueNumbering) {
vmap()->kill_all();
}
_memory->kill();
}
BlockBegin* GraphBuilder::ScopeData::block_at(int bci) {
if (parsing_jsr()) {
// It is necessary to clone all blocks associated with a
// subroutine, including those for exception handlers in the scope
// of the method containing the jsr (because those exception
// handlers may contain ret instructions in some cases).
BlockBegin* block = bci2block()->at(bci);
if (block != NULL && block == parent()->bci2block()->at(bci)) {
BlockBegin* new_block = new BlockBegin(block->bci());
if (PrintInitialBlockList) {
tty->print_cr("CFG: cloned block %d (bci %d) as block %d for jsr",
block->block_id(), block->bci(), new_block->block_id());
}
// copy data from cloned blocked
new_block->set_depth_first_number(block->depth_first_number());
if (block->is_set(BlockBegin::parser_loop_header_flag)) new_block->set(BlockBegin::parser_loop_header_flag);
// Preserve certain flags for assertion checking
if (block->is_set(BlockBegin::subroutine_entry_flag)) new_block->set(BlockBegin::subroutine_entry_flag);
if (block->is_set(BlockBegin::exception_entry_flag)) new_block->set(BlockBegin::exception_entry_flag);
// copy was_visited_flag to allow early detection of bailouts
// if a block that is used in a jsr has already been visited before,
// it is shared between the normal control flow and a subroutine
// BlockBegin::try_merge returns false when the flag is set, this leads
// to a compilation bailout
if (block->is_set(BlockBegin::was_visited_flag)) new_block->set(BlockBegin::was_visited_flag);
bci2block()->at_put(bci, new_block);
block = new_block;
}
return block;
} else {
return bci2block()->at(bci);
}
}
XHandlers* GraphBuilder::ScopeData::xhandlers() const {
if (_jsr_xhandlers == NULL) {
assert(!parsing_jsr(), "");
return scope()->xhandlers();
}
assert(parsing_jsr(), "");
return _jsr_xhandlers;
}
void GraphBuilder::ScopeData::set_scope(IRScope* scope) {
_scope = scope;
bool parent_has_handler = false;
if (parent() != NULL) {
parent_has_handler = parent()->has_handler();
}
_has_handler = parent_has_handler || scope->xhandlers()->has_handlers();
}
void GraphBuilder::ScopeData::set_inline_cleanup_info(BlockBegin* block,
Instruction* return_prev,
ValueStack* return_state) {
_cleanup_block = block;
_cleanup_return_prev = return_prev;
_cleanup_state = return_state;
}
void GraphBuilder::ScopeData::add_to_work_list(BlockBegin* block) {
if (_work_list == NULL) {
_work_list = new BlockList();
}
if (!block->is_set(BlockBegin::is_on_work_list_flag)) {
// Do not start parsing the continuation block while in a
// sub-scope
if (parsing_jsr()) {
if (block == jsr_continuation()) {
return;
}
} else {
if (block == continuation()) {
return;
}
}
block->set(BlockBegin::is_on_work_list_flag);
_work_list->push(block);
sort_top_into_worklist(_work_list, block);
}
}
void GraphBuilder::sort_top_into_worklist(BlockList* worklist, BlockBegin* top) {
assert(worklist->top() == top, "");
// sort block descending into work list
const int dfn = top->depth_first_number();
assert(dfn != -1, "unknown depth first number");
int i = worklist->length()-2;
while (i >= 0) {
BlockBegin* b = worklist->at(i);
if (b->depth_first_number() < dfn) {
worklist->at_put(i+1, b);
} else {
break;
}
i --;
}
if (i >= -1) worklist->at_put(i + 1, top);
}
BlockBegin* GraphBuilder::ScopeData::remove_from_work_list() {
if (is_work_list_empty()) {
return NULL;
}
return _work_list->pop();
}
bool GraphBuilder::ScopeData::is_work_list_empty() const {
return (_work_list == NULL || _work_list->length() == 0);
}
void GraphBuilder::ScopeData::setup_jsr_xhandlers() {
assert(parsing_jsr(), "");
// clone all the exception handlers from the scope
XHandlers* handlers = new XHandlers(scope()->xhandlers());
const int n = handlers->length();
for (int i = 0; i < n; i++) {
// The XHandlers need to be adjusted to dispatch to the cloned
// handler block instead of the default one but the synthetic
// unlocker needs to be handled specially. The synthetic unlocker
// should be left alone since there can be only one and all code
// should dispatch to the same one.
XHandler* h = handlers->handler_at(i);
assert(h->handler_bci() != SynchronizationEntryBCI, "must be real");
h->set_entry_block(block_at(h->handler_bci()));
}
_jsr_xhandlers = handlers;
}
int GraphBuilder::ScopeData::num_returns() {
if (parsing_jsr()) {
return parent()->num_returns();
}
return _num_returns;
}
void GraphBuilder::ScopeData::incr_num_returns() {
if (parsing_jsr()) {
parent()->incr_num_returns();
} else {
++_num_returns;
}
}
// Implementation of GraphBuilder
#define INLINE_BAILOUT(msg) { inline_bailout(msg); return false; }
void GraphBuilder::load_constant() {
ciConstant con = stream()->get_constant();
if (con.basic_type() == T_ILLEGAL) {
// FIXME: an unresolved Dynamic constant can get here,
// and that should not terminate the whole compilation.
BAILOUT("could not resolve a constant");
} else {
ValueType* t = illegalType;
ValueStack* patch_state = NULL;
switch (con.basic_type()) {
case T_BOOLEAN: t = new IntConstant (con.as_boolean()); break;
case T_BYTE : t = new IntConstant (con.as_byte ()); break;
case T_CHAR : t = new IntConstant (con.as_char ()); break;
case T_SHORT : t = new IntConstant (con.as_short ()); break;
case T_INT : t = new IntConstant (con.as_int ()); break;
case T_LONG : t = new LongConstant (con.as_long ()); break;
case T_FLOAT : t = new FloatConstant (con.as_float ()); break;
case T_DOUBLE : t = new DoubleConstant (con.as_double ()); break;
case T_ARRAY : t = new ArrayConstant (con.as_object ()->as_array ()); break;
case T_OBJECT :
{
ciObject* obj = con.as_object();
if (!obj->is_loaded()
|| (PatchALot && obj->klass() != ciEnv::current()->String_klass())) {
// A Class, MethodType, MethodHandle, or String.
// Unloaded condy nodes show up as T_ILLEGAL, above.
patch_state = copy_state_before();
t = new ObjectConstant(obj);
} else {
// Might be a Class, MethodType, MethodHandle, or Dynamic constant
// result, which might turn out to be an array.
if (obj->is_null_object())
t = objectNull;
else if (obj->is_array())
t = new ArrayConstant(obj->as_array());
else
t = new InstanceConstant(obj->as_instance());
}
break;
}
default : ShouldNotReachHere();
}
Value x;
if (patch_state != NULL) {
x = new Constant(t, patch_state);
} else {
x = new Constant(t);
}
push(t, append(x));
}
}
void GraphBuilder::load_local(ValueType* type, int index) {
Value x = state()->local_at(index);
assert(x != NULL && !x->type()->is_illegal(), "access of illegal local variable");
push(type, x);
if (x->as_NewInlineTypeInstance() != NULL && x->as_NewInlineTypeInstance()->in_larval_state()) {
if (x->as_NewInlineTypeInstance()->on_stack_count() == 1) {
x->as_NewInlineTypeInstance()->set_not_larva_anymore();
} else {
x->as_NewInlineTypeInstance()->increment_on_stack_count();
}
}
}
void GraphBuilder::store_local(ValueType* type, int index) {
Value x = pop(type);
store_local(state(), x, index);
if (x->as_NewInlineTypeInstance() != NULL) {
x->as_NewInlineTypeInstance()->set_local_index(index);
}
}
void GraphBuilder::store_local(ValueStack* state, Value x, int index) {
if (parsing_jsr()) {
// We need to do additional tracking of the location of the return
// address for jsrs since we don't handle arbitrary jsr/ret
// constructs. Here we are figuring out in which circumstances we
// need to bail out.
if (x->type()->is_address()) {
scope_data()->set_jsr_return_address_local(index);
// Also check parent jsrs (if any) at this time to see whether
// they are using this local. We don't handle skipping over a
// ret.
for (ScopeData* cur_scope_data = scope_data()->parent();
cur_scope_data != NULL && cur_scope_data->parsing_jsr() && cur_scope_data->scope() == scope();
cur_scope_data = cur_scope_data->parent()) {
if (cur_scope_data->jsr_return_address_local() == index) {
BAILOUT("subroutine overwrites return address from previous subroutine");
}
}
} else if (index == scope_data()->jsr_return_address_local()) {
scope_data()->set_jsr_return_address_local(-1);
}
}
state->store_local(index, round_fp(x));
if (x->as_NewInlineTypeInstance() != NULL) {
x->as_NewInlineTypeInstance()->set_local_index(index);