6862919: Update copyright year
Summary: Update copyright for files that have been modified in 2009, up to 07/09
Reviewed-by: tbell, ohair
/*
* Copyright 2005-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
*/
#include "incls/_precompiled.incl"
#include "incls/_escape.cpp.incl"
void PointsToNode::add_edge(uint targIdx, PointsToNode::EdgeType et) {
uint v = (targIdx << EdgeShift) + ((uint) et);
if (_edges == NULL) {
Arena *a = Compile::current()->comp_arena();
_edges = new(a) GrowableArray<uint>(a, INITIAL_EDGE_COUNT, 0, 0);
}
_edges->append_if_missing(v);
}
void PointsToNode::remove_edge(uint targIdx, PointsToNode::EdgeType et) {
uint v = (targIdx << EdgeShift) + ((uint) et);
_edges->remove(v);
}
#ifndef PRODUCT
static const char *node_type_names[] = {
"UnknownType",
"JavaObject",
"LocalVar",
"Field"
};
static const char *esc_names[] = {
"UnknownEscape",
"NoEscape",
"ArgEscape",
"GlobalEscape"
};
static const char *edge_type_suffix[] = {
"?", // UnknownEdge
"P", // PointsToEdge
"D", // DeferredEdge
"F" // FieldEdge
};
void PointsToNode::dump(bool print_state) const {
NodeType nt = node_type();
tty->print("%s ", node_type_names[(int) nt]);
if (print_state) {
EscapeState es = escape_state();
tty->print("%s %s ", esc_names[(int) es], _scalar_replaceable ? "":"NSR");
}
tty->print("[[");
for (uint i = 0; i < edge_count(); i++) {
tty->print(" %d%s", edge_target(i), edge_type_suffix[(int) edge_type(i)]);
}
tty->print("]] ");
if (_node == NULL)
tty->print_cr("<null>");
else
_node->dump();
}
#endif
ConnectionGraph::ConnectionGraph(Compile * C) :
_nodes(C->comp_arena(), C->unique(), C->unique(), PointsToNode()),
_processed(C->comp_arena()),
_collecting(true),
_compile(C),
_node_map(C->comp_arena()) {
_phantom_object = C->top()->_idx,
add_node(C->top(), PointsToNode::JavaObject, PointsToNode::GlobalEscape,true);
// Add ConP(#NULL) and ConN(#NULL) nodes.
PhaseGVN* igvn = C->initial_gvn();
Node* oop_null = igvn->zerocon(T_OBJECT);
_oop_null = oop_null->_idx;
assert(_oop_null < C->unique(), "should be created already");
add_node(oop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
if (UseCompressedOops) {
Node* noop_null = igvn->zerocon(T_NARROWOOP);
_noop_null = noop_null->_idx;
assert(_noop_null < C->unique(), "should be created already");
add_node(noop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
}
}
void ConnectionGraph::add_pointsto_edge(uint from_i, uint to_i) {
PointsToNode *f = ptnode_adr(from_i);
PointsToNode *t = ptnode_adr(to_i);
assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of PointsTo edge");
assert(t->node_type() == PointsToNode::JavaObject, "invalid destination of PointsTo edge");
f->add_edge(to_i, PointsToNode::PointsToEdge);
}
void ConnectionGraph::add_deferred_edge(uint from_i, uint to_i) {
PointsToNode *f = ptnode_adr(from_i);
PointsToNode *t = ptnode_adr(to_i);
assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of Deferred edge");
assert(t->node_type() == PointsToNode::LocalVar || t->node_type() == PointsToNode::Field, "invalid destination of Deferred edge");
// don't add a self-referential edge, this can occur during removal of
// deferred edges
if (from_i != to_i)
f->add_edge(to_i, PointsToNode::DeferredEdge);
}
int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
const Type *adr_type = phase->type(adr);
if (adr->is_AddP() && adr_type->isa_oopptr() == NULL &&
adr->in(AddPNode::Address)->is_Proj() &&
adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
// We are computing a raw address for a store captured by an Initialize
// compute an appropriate address type. AddP cases #3 and #5 (see below).
int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
assert(offs != Type::OffsetBot ||
adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
"offset must be a constant or it is initialization of array");
return offs;
}
const TypePtr *t_ptr = adr_type->isa_ptr();
assert(t_ptr != NULL, "must be a pointer type");
return t_ptr->offset();
}
void ConnectionGraph::add_field_edge(uint from_i, uint to_i, int offset) {
PointsToNode *f = ptnode_adr(from_i);
PointsToNode *t = ptnode_adr(to_i);
assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
assert(f->node_type() == PointsToNode::JavaObject, "invalid destination of Field edge");
assert(t->node_type() == PointsToNode::Field, "invalid destination of Field edge");
assert (t->offset() == -1 || t->offset() == offset, "conflicting field offsets");
t->set_offset(offset);
f->add_edge(to_i, PointsToNode::FieldEdge);
}
void ConnectionGraph::set_escape_state(uint ni, PointsToNode::EscapeState es) {
PointsToNode *npt = ptnode_adr(ni);
PointsToNode::EscapeState old_es = npt->escape_state();
if (es > old_es)
npt->set_escape_state(es);
}
void ConnectionGraph::add_node(Node *n, PointsToNode::NodeType nt,
PointsToNode::EscapeState es, bool done) {
PointsToNode* ptadr = ptnode_adr(n->_idx);
ptadr->_node = n;
ptadr->set_node_type(nt);
// inline set_escape_state(idx, es);
PointsToNode::EscapeState old_es = ptadr->escape_state();
if (es > old_es)
ptadr->set_escape_state(es);
if (done)
_processed.set(n->_idx);
}
PointsToNode::EscapeState ConnectionGraph::escape_state(Node *n, PhaseTransform *phase) {
uint idx = n->_idx;
PointsToNode::EscapeState es;
// If we are still collecting or there were no non-escaping allocations
// we don't know the answer yet
if (_collecting)
return PointsToNode::UnknownEscape;
// if the node was created after the escape computation, return
// UnknownEscape
if (idx >= nodes_size())
return PointsToNode::UnknownEscape;
es = ptnode_adr(idx)->escape_state();
// if we have already computed a value, return it
if (es != PointsToNode::UnknownEscape &&
ptnode_adr(idx)->node_type() == PointsToNode::JavaObject)
return es;
// PointsTo() calls n->uncast() which can return a new ideal node.
if (n->uncast()->_idx >= nodes_size())
return PointsToNode::UnknownEscape;
// compute max escape state of anything this node could point to
VectorSet ptset(Thread::current()->resource_area());
PointsTo(ptset, n, phase);
for(VectorSetI i(&ptset); i.test() && es != PointsToNode::GlobalEscape; ++i) {
uint pt = i.elem;
PointsToNode::EscapeState pes = ptnode_adr(pt)->escape_state();
if (pes > es)
es = pes;
}
// cache the computed escape state
assert(es != PointsToNode::UnknownEscape, "should have computed an escape state");
ptnode_adr(idx)->set_escape_state(es);
return es;
}
void ConnectionGraph::PointsTo(VectorSet &ptset, Node * n, PhaseTransform *phase) {
VectorSet visited(Thread::current()->resource_area());
GrowableArray<uint> worklist;
#ifdef ASSERT
Node *orig_n = n;
#endif
n = n->uncast();
PointsToNode* npt = ptnode_adr(n->_idx);
// If we have a JavaObject, return just that object
if (npt->node_type() == PointsToNode::JavaObject) {
ptset.set(n->_idx);
return;
}
#ifdef ASSERT
if (npt->_node == NULL) {
if (orig_n != n)
orig_n->dump();
n->dump();
assert(npt->_node != NULL, "unregistered node");
}
#endif
worklist.push(n->_idx);
while(worklist.length() > 0) {
int ni = worklist.pop();
if (visited.test_set(ni))
continue;
PointsToNode* pn = ptnode_adr(ni);
// ensure that all inputs of a Phi have been processed
assert(!_collecting || !pn->_node->is_Phi() || _processed.test(ni),"");
int edges_processed = 0;
uint e_cnt = pn->edge_count();
for (uint e = 0; e < e_cnt; e++) {
uint etgt = pn->edge_target(e);
PointsToNode::EdgeType et = pn->edge_type(e);
if (et == PointsToNode::PointsToEdge) {
ptset.set(etgt);
edges_processed++;
} else if (et == PointsToNode::DeferredEdge) {
worklist.push(etgt);
edges_processed++;
} else {
assert(false,"neither PointsToEdge or DeferredEdge");
}
}
if (edges_processed == 0) {
// no deferred or pointsto edges found. Assume the value was set
// outside this method. Add the phantom object to the pointsto set.
ptset.set(_phantom_object);
}
}
}
void ConnectionGraph::remove_deferred(uint ni, GrowableArray<uint>* deferred_edges, VectorSet* visited) {
// This method is most expensive during ConnectionGraph construction.
// Reuse vectorSet and an additional growable array for deferred edges.
deferred_edges->clear();
visited->Clear();
visited->set(ni);
PointsToNode *ptn = ptnode_adr(ni);
// Mark current edges as visited and move deferred edges to separate array.
for (uint i = 0; i < ptn->edge_count(); ) {
uint t = ptn->edge_target(i);
#ifdef ASSERT
assert(!visited->test_set(t), "expecting no duplications");
#else
visited->set(t);
#endif
if (ptn->edge_type(i) == PointsToNode::DeferredEdge) {
ptn->remove_edge(t, PointsToNode::DeferredEdge);
deferred_edges->append(t);
} else {
i++;
}
}
for (int next = 0; next < deferred_edges->length(); ++next) {
uint t = deferred_edges->at(next);
PointsToNode *ptt = ptnode_adr(t);
uint e_cnt = ptt->edge_count();
for (uint e = 0; e < e_cnt; e++) {
uint etgt = ptt->edge_target(e);
if (visited->test_set(etgt))
continue;
PointsToNode::EdgeType et = ptt->edge_type(e);
if (et == PointsToNode::PointsToEdge) {
add_pointsto_edge(ni, etgt);
if(etgt == _phantom_object) {
// Special case - field set outside (globally escaping).
ptn->set_escape_state(PointsToNode::GlobalEscape);
}
} else if (et == PointsToNode::DeferredEdge) {
deferred_edges->append(etgt);
} else {
assert(false,"invalid connection graph");
}
}
}
}
// Add an edge to node given by "to_i" from any field of adr_i whose offset
// matches "offset" A deferred edge is added if to_i is a LocalVar, and
// a pointsto edge is added if it is a JavaObject
void ConnectionGraph::add_edge_from_fields(uint adr_i, uint to_i, int offs) {
PointsToNode* an = ptnode_adr(adr_i);
PointsToNode* to = ptnode_adr(to_i);
bool deferred = (to->node_type() == PointsToNode::LocalVar);
for (uint fe = 0; fe < an->edge_count(); fe++) {
assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
int fi = an->edge_target(fe);
PointsToNode* pf = ptnode_adr(fi);
int po = pf->offset();
if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
if (deferred)
add_deferred_edge(fi, to_i);
else
add_pointsto_edge(fi, to_i);
}
}
}
// Add a deferred edge from node given by "from_i" to any field of adr_i
// whose offset matches "offset".
void ConnectionGraph::add_deferred_edge_to_fields(uint from_i, uint adr_i, int offs) {
PointsToNode* an = ptnode_adr(adr_i);
for (uint fe = 0; fe < an->edge_count(); fe++) {
assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
int fi = an->edge_target(fe);
PointsToNode* pf = ptnode_adr(fi);
int po = pf->offset();
if (pf->edge_count() == 0) {
// we have not seen any stores to this field, assume it was set outside this method
add_pointsto_edge(fi, _phantom_object);
}
if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
add_deferred_edge(from_i, fi);
}
}
}
// Helper functions
static Node* get_addp_base(Node *addp) {
assert(addp->is_AddP(), "must be AddP");
//
// AddP cases for Base and Address inputs:
// case #1. Direct object's field reference:
// Allocate
// |
// Proj #5 ( oop result )
// |
// CheckCastPP (cast to instance type)
// | |
// AddP ( base == address )
//
// case #2. Indirect object's field reference:
// Phi
// |
// CastPP (cast to instance type)
// | |
// AddP ( base == address )
//
// case #3. Raw object's field reference for Initialize node:
// Allocate
// |
// Proj #5 ( oop result )
// top |
// \ |
// AddP ( base == top )
//
// case #4. Array's element reference:
// {CheckCastPP | CastPP}
// | | |
// | AddP ( array's element offset )
// | |
// AddP ( array's offset )
//
// case #5. Raw object's field reference for arraycopy stub call:
// The inline_native_clone() case when the arraycopy stub is called
// after the allocation before Initialize and CheckCastPP nodes.
// Allocate
// |
// Proj #5 ( oop result )
// | |
// AddP ( base == address )
//
// case #6. Constant Pool, ThreadLocal, CastX2P or
// Raw object's field reference:
// {ConP, ThreadLocal, CastX2P, raw Load}
// top |
// \ |
// AddP ( base == top )
//
// case #7. Klass's field reference.
// LoadKlass
// | |
// AddP ( base == address )
//
// case #8. narrow Klass's field reference.
// LoadNKlass
// |
// DecodeN
// | |
// AddP ( base == address )
//
Node *base = addp->in(AddPNode::Base)->uncast();
if (base->is_top()) { // The AddP case #3 and #6.
base = addp->in(AddPNode::Address)->uncast();
assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal ||
base->Opcode() == Op_CastX2P || base->is_DecodeN() ||
(base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) ||
(base->is_Proj() && base->in(0)->is_Allocate()), "sanity");
}
return base;
}
static Node* find_second_addp(Node* addp, Node* n) {
assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
Node* addp2 = addp->raw_out(0);
if (addp->outcnt() == 1 && addp2->is_AddP() &&
addp2->in(AddPNode::Base) == n &&
addp2->in(AddPNode::Address) == addp) {
assert(addp->in(AddPNode::Base) == n, "expecting the same base");
//
// Find array's offset to push it on worklist first and
// as result process an array's element offset first (pushed second)
// to avoid CastPP for the array's offset.
// Otherwise the inserted CastPP (LocalVar) will point to what
// the AddP (Field) points to. Which would be wrong since
// the algorithm expects the CastPP has the same point as
// as AddP's base CheckCastPP (LocalVar).
//
// ArrayAllocation
// |
// CheckCastPP
// |
// memProj (from ArrayAllocation CheckCastPP)
// | ||
// | || Int (element index)
// | || | ConI (log(element size))
// | || | /
// | || LShift
// | || /
// | AddP (array's element offset)
// | |
// | | ConI (array's offset: #12(32-bits) or #24(64-bits))
// | / /
// AddP (array's offset)
// |
// Load/Store (memory operation on array's element)
//
return addp2;
}
return NULL;
}
//
// Adjust the type and inputs of an AddP which computes the
// address of a field of an instance
//
bool ConnectionGraph::split_AddP(Node *addp, Node *base, PhaseGVN *igvn) {
const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
if (t == NULL) {
// We are computing a raw address for a store captured by an Initialize
// compute an appropriate address type (cases #3 and #5).
assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
assert(offs != Type::OffsetBot, "offset must be a constant");
t = base_t->add_offset(offs)->is_oopptr();
}
int inst_id = base_t->instance_id();
assert(!t->is_known_instance() || t->instance_id() == inst_id,
"old type must be non-instance or match new type");
// The type 't' could be subclass of 'base_t'.
// As result t->offset() could be large then base_t's size and it will
// cause the failure in add_offset() with narrow oops since TypeOopPtr()
// constructor verifies correctness of the offset.
//
// It could happened on subclass's branch (from the type profiling
// inlining) which was not eliminated during parsing since the exactness
// of the allocation type was not propagated to the subclass type check.
//
// Do nothing for such AddP node and don't process its users since
// this code branch will go away.
//
if (!t->is_known_instance() &&
!t->klass()->equals(base_t->klass()) &&
t->klass()->is_subtype_of(base_t->klass())) {
return false; // bail out
}
const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
// Do NOT remove the next call: ensure an new alias index is allocated
// for the instance type
int alias_idx = _compile->get_alias_index(tinst);
igvn->set_type(addp, tinst);
// record the allocation in the node map
set_map(addp->_idx, get_map(base->_idx));
// Set addp's Base and Address to 'base'.
Node *abase = addp->in(AddPNode::Base);
Node *adr = addp->in(AddPNode::Address);
if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
adr->in(0)->_idx == (uint)inst_id) {
// Skip AddP cases #3 and #5.
} else {
assert(!abase->is_top(), "sanity"); // AddP case #3
if (abase != base) {
igvn->hash_delete(addp);
addp->set_req(AddPNode::Base, base);
if (abase == adr) {
addp->set_req(AddPNode::Address, base);
} else {
// AddP case #4 (adr is array's element offset AddP node)
#ifdef ASSERT
const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
assert(adr->is_AddP() && atype != NULL &&
atype->instance_id() == inst_id, "array's element offset should be processed first");
#endif
}
igvn->hash_insert(addp);
}
}
// Put on IGVN worklist since at least addp's type was changed above.
record_for_optimizer(addp);
return true;
}
//
// Create a new version of orig_phi if necessary. Returns either the newly
// created phi or an existing phi. Sets create_new to indicate wheter a new
// phi was created. Cache the last newly created phi in the node map.
//
PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, PhaseGVN *igvn, bool &new_created) {
Compile *C = _compile;
new_created = false;
int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
// nothing to do if orig_phi is bottom memory or matches alias_idx
if (phi_alias_idx == alias_idx) {
return orig_phi;
}
// have we already created a Phi for this alias index?
PhiNode *result = get_map_phi(orig_phi->_idx);
if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
return result;
}
if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) {
if (C->do_escape_analysis() == true && !C->failing()) {
// Retry compilation without escape analysis.
// If this is the first failure, the sentinel string will "stick"
// to the Compile object, and the C2Compiler will see it and retry.
C->record_failure(C2Compiler::retry_no_escape_analysis());
}
return NULL;
}
orig_phi_worklist.append_if_missing(orig_phi);
const TypePtr *atype = C->get_adr_type(alias_idx);
result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
set_map_phi(orig_phi->_idx, result);
igvn->set_type(result, result->bottom_type());
record_for_optimizer(result);
new_created = true;
return result;
}
//
// Return a new version of Memory Phi "orig_phi" with the inputs having the
// specified alias index.
//
PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, PhaseGVN *igvn) {
assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
Compile *C = _compile;
bool new_phi_created;
PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created);
if (!new_phi_created) {
return result;
}
GrowableArray<PhiNode *> phi_list;
GrowableArray<uint> cur_input;
PhiNode *phi = orig_phi;
uint idx = 1;
bool finished = false;
while(!finished) {
while (idx < phi->req()) {
Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn);
if (mem != NULL && mem->is_Phi()) {
PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created);
if (new_phi_created) {
// found an phi for which we created a new split, push current one on worklist and begin
// processing new one
phi_list.push(phi);
cur_input.push(idx);
phi = mem->as_Phi();
result = newphi;
idx = 1;
continue;
} else {
mem = newphi;
}
}
if (C->failing()) {
return NULL;
}
result->set_req(idx++, mem);
}
#ifdef ASSERT
// verify that the new Phi has an input for each input of the original
assert( phi->req() == result->req(), "must have same number of inputs.");
assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
#endif
// Check if all new phi's inputs have specified alias index.
// Otherwise use old phi.
for (uint i = 1; i < phi->req(); i++) {
Node* in = result->in(i);
assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
}
// we have finished processing a Phi, see if there are any more to do
finished = (phi_list.length() == 0 );
if (!finished) {
phi = phi_list.pop();
idx = cur_input.pop();
PhiNode *prev_result = get_map_phi(phi->_idx);
prev_result->set_req(idx++, result);
result = prev_result;
}
}
return result;
}
//
// The next methods are derived from methods in MemNode.
//
static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *tinst) {
Node *mem = mmem;
// TypeInstPtr::NOTNULL+any is an OOP with unknown offset - generally
// means an array I have not precisely typed yet. Do not do any
// alias stuff with it any time soon.
if( tinst->base() != Type::AnyPtr &&
!(tinst->klass()->is_java_lang_Object() &&
tinst->offset() == Type::OffsetBot) ) {
mem = mmem->memory_at(alias_idx);
// Update input if it is progress over what we have now
}
return mem;
}
//
// Search memory chain of "mem" to find a MemNode whose address
// is the specified alias index.
//
Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis, PhaseGVN *phase) {
if (orig_mem == NULL)
return orig_mem;
Compile* C = phase->C;
const TypeOopPtr *tinst = C->get_adr_type(alias_idx)->isa_oopptr();
bool is_instance = (tinst != NULL) && tinst->is_known_instance();
Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
Node *prev = NULL;
Node *result = orig_mem;
while (prev != result) {
prev = result;
if (result == start_mem)
break; // hit one of our sentinels
if (result->is_Mem()) {
const Type *at = phase->type(result->in(MemNode::Address));
if (at != Type::TOP) {
assert (at->isa_ptr() != NULL, "pointer type required.");
int idx = C->get_alias_index(at->is_ptr());
if (idx == alias_idx)
break;
}
result = result->in(MemNode::Memory);
}
if (!is_instance)
continue; // don't search further for non-instance types
// skip over a call which does not affect this memory slice
if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
Node *proj_in = result->in(0);
if (proj_in->is_Allocate() && proj_in->_idx == (uint)tinst->instance_id()) {
break; // hit one of our sentinels
} else if (proj_in->is_Call()) {
CallNode *call = proj_in->as_Call();
if (!call->may_modify(tinst, phase)) {
result = call->in(TypeFunc::Memory);
}
} else if (proj_in->is_Initialize()) {
AllocateNode* alloc = proj_in->as_Initialize()->allocation();
// Stop if this is the initialization for the object instance which
// which contains this memory slice, otherwise skip over it.
if (alloc == NULL || alloc->_idx != (uint)tinst->instance_id()) {
result = proj_in->in(TypeFunc::Memory);
}
} else if (proj_in->is_MemBar()) {
result = proj_in->in(TypeFunc::Memory);
}
} else if (result->is_MergeMem()) {
MergeMemNode *mmem = result->as_MergeMem();
result = step_through_mergemem(mmem, alias_idx, tinst);
if (result == mmem->base_memory()) {
// Didn't find instance memory, search through general slice recursively.
result = mmem->memory_at(C->get_general_index(alias_idx));
result = find_inst_mem(result, alias_idx, orig_phis, phase);
if (C->failing()) {
return NULL;
}
mmem->set_memory_at(alias_idx, result);
}
} else if (result->is_Phi() &&
C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
Node *un = result->as_Phi()->unique_input(phase);
if (un != NULL) {
result = un;
} else {
break;
}
} else if (result->Opcode() == Op_SCMemProj) {
assert(result->in(0)->is_LoadStore(), "sanity");
const Type *at = phase->type(result->in(0)->in(MemNode::Address));
if (at != Type::TOP) {
assert (at->isa_ptr() != NULL, "pointer type required.");
int idx = C->get_alias_index(at->is_ptr());
assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field");
break;
}
result = result->in(0)->in(MemNode::Memory);
}
}
if (result->is_Phi()) {
PhiNode *mphi = result->as_Phi();
assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
const TypePtr *t = mphi->adr_type();
if (C->get_alias_index(t) != alias_idx) {
// Create a new Phi with the specified alias index type.
result = split_memory_phi(mphi, alias_idx, orig_phis, phase);
} else if (!is_instance) {
// Push all non-instance Phis on the orig_phis worklist to update inputs
// during Phase 4 if needed.
orig_phis.append_if_missing(mphi);
}
}
// the result is either MemNode, PhiNode, InitializeNode.
return result;
}
//
// Convert the types of unescaped object to instance types where possible,
// propagate the new type information through the graph, and update memory
// edges and MergeMem inputs to reflect the new type.
//
// We start with allocations (and calls which may be allocations) on alloc_worklist.
// The processing is done in 4 phases:
//
// Phase 1: Process possible allocations from alloc_worklist. Create instance
// types for the CheckCastPP for allocations where possible.
// Propagate the the new types through users as follows:
// casts and Phi: push users on alloc_worklist
// AddP: cast Base and Address inputs to the instance type
// push any AddP users on alloc_worklist and push any memnode
// users onto memnode_worklist.
// Phase 2: Process MemNode's from memnode_worklist. compute new address type and
// search the Memory chain for a store with the appropriate type
// address type. If a Phi is found, create a new version with
// the appropriate memory slices from each of the Phi inputs.
// For stores, process the users as follows:
// MemNode: push on memnode_worklist
// MergeMem: push on mergemem_worklist
// Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
// moving the first node encountered of each instance type to the
// the input corresponding to its alias index.
// appropriate memory slice.
// Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
//
// In the following example, the CheckCastPP nodes are the cast of allocation
// results and the allocation of node 29 is unescaped and eligible to be an
// instance type.
//
// We start with:
//
// 7 Parm #memory
// 10 ConI "12"
// 19 CheckCastPP "Foo"
// 20 AddP _ 19 19 10 Foo+12 alias_index=4
// 29 CheckCastPP "Foo"
// 30 AddP _ 29 29 10 Foo+12 alias_index=4
//
// 40 StoreP 25 7 20 ... alias_index=4
// 50 StoreP 35 40 30 ... alias_index=4
// 60 StoreP 45 50 20 ... alias_index=4
// 70 LoadP _ 60 30 ... alias_index=4
// 80 Phi 75 50 60 Memory alias_index=4
// 90 LoadP _ 80 30 ... alias_index=4
// 100 LoadP _ 80 20 ... alias_index=4
//
//
// Phase 1 creates an instance type for node 29 assigning it an instance id of 24
// and creating a new alias index for node 30. This gives:
//
// 7 Parm #memory
// 10 ConI "12"
// 19 CheckCastPP "Foo"
// 20 AddP _ 19 19 10 Foo+12 alias_index=4
// 29 CheckCastPP "Foo" iid=24
// 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
//
// 40 StoreP 25 7 20 ... alias_index=4
// 50 StoreP 35 40 30 ... alias_index=6
// 60 StoreP 45 50 20 ... alias_index=4
// 70 LoadP _ 60 30 ... alias_index=6
// 80 Phi 75 50 60 Memory alias_index=4
// 90 LoadP _ 80 30 ... alias_index=6
// 100 LoadP _ 80 20 ... alias_index=4
//
// In phase 2, new memory inputs are computed for the loads and stores,
// And a new version of the phi is created. In phase 4, the inputs to
// node 80 are updated and then the memory nodes are updated with the
// values computed in phase 2. This results in:
//
// 7 Parm #memory
// 10 ConI "12"
// 19 CheckCastPP "Foo"
// 20 AddP _ 19 19 10 Foo+12 alias_index=4
// 29 CheckCastPP "Foo" iid=24
// 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
//
// 40 StoreP 25 7 20 ... alias_index=4
// 50 StoreP 35 7 30 ... alias_index=6
// 60 StoreP 45 40 20 ... alias_index=4
// 70 LoadP _ 50 30 ... alias_index=6
// 80 Phi 75 40 60 Memory alias_index=4
// 120 Phi 75 50 50 Memory alias_index=6
// 90 LoadP _ 120 30 ... alias_index=6
// 100 LoadP _ 80 20 ... alias_index=4
//
void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist) {
GrowableArray<Node *> memnode_worklist;
GrowableArray<Node *> mergemem_worklist;
GrowableArray<PhiNode *> orig_phis;
PhaseGVN *igvn = _compile->initial_gvn();
uint new_index_start = (uint) _compile->num_alias_types();
VectorSet visited(Thread::current()->resource_area());
VectorSet ptset(Thread::current()->resource_area());
// Phase 1: Process possible allocations from alloc_worklist.
// Create instance types for the CheckCastPP for allocations where possible.
//
// (Note: don't forget to change the order of the second AddP node on
// the alloc_worklist if the order of the worklist processing is changed,
// see the comment in find_second_addp().)
//
while (alloc_worklist.length() != 0) {
Node *n = alloc_worklist.pop();
uint ni = n->_idx;
const TypeOopPtr* tinst = NULL;
if (n->is_Call()) {
CallNode *alloc = n->as_Call();
// copy escape information to call node
PointsToNode* ptn = ptnode_adr(alloc->_idx);
PointsToNode::EscapeState es = escape_state(alloc, igvn);
// We have an allocation or call which returns a Java object,
// see if it is unescaped.
if (es != PointsToNode::NoEscape || !ptn->_scalar_replaceable)
continue;
// Find CheckCastPP for the allocate or for the return value of a call
n = alloc->result_cast();
if (n == NULL) { // No uses except Initialize node
if (alloc->is_Allocate()) {
// Set the scalar_replaceable flag for allocation
// so it could be eliminated if it has no uses.
alloc->as_Allocate()->_is_scalar_replaceable = true;
}
continue;
}
if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
assert(!alloc->is_Allocate(), "allocation should have unique type");
continue;
}
// The inline code for Object.clone() casts the allocation result to
// java.lang.Object and then to the actual type of the allocated
// object. Detect this case and use the second cast.
// Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
// the allocation result is cast to java.lang.Object and then
// to the actual Array type.
if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
&& (alloc->is_AllocateArray() ||
igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
Node *cast2 = NULL;
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node *use = n->fast_out(i);
if (use->is_CheckCastPP()) {
cast2 = use;
break;
}
}
if (cast2 != NULL) {
n = cast2;
} else {
// Non-scalar replaceable if the allocation type is unknown statically
// (reflection allocation), the object can't be restored during
// deoptimization without precise type.
continue;
}
}
if (alloc->is_Allocate()) {
// Set the scalar_replaceable flag for allocation
// so it could be eliminated.
alloc->as_Allocate()->_is_scalar_replaceable = true;
}
set_escape_state(n->_idx, es);
// in order for an object to be scalar-replaceable, it must be:
// - a direct allocation (not a call returning an object)
// - non-escaping
// - eligible to be a unique type
// - not determined to be ineligible by escape analysis
set_map(alloc->_idx, n);
set_map(n->_idx, alloc);
const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
if (t == NULL)
continue; // not a TypeInstPtr
tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni);
igvn->hash_delete(n);
igvn->set_type(n, tinst);
n->raise_bottom_type(tinst);
igvn->hash_insert(n);
record_for_optimizer(n);
if (alloc->is_Allocate() && ptn->_scalar_replaceable &&
(t->isa_instptr() || t->isa_aryptr())) {
// First, put on the worklist all Field edges from Connection Graph
// which is more accurate then putting immediate users from Ideal Graph.
for (uint e = 0; e < ptn->edge_count(); e++) {
Node *use = ptnode_adr(ptn->edge_target(e))->_node;
assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(),
"only AddP nodes are Field edges in CG");
if (use->outcnt() > 0) { // Don't process dead nodes
Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
if (addp2 != NULL) {
assert(alloc->is_AllocateArray(),"array allocation was expected");
alloc_worklist.append_if_missing(addp2);
}
alloc_worklist.append_if_missing(use);
}
}
// An allocation may have an Initialize which has raw stores. Scan
// the users of the raw allocation result and push AddP users
// on alloc_worklist.
Node *raw_result = alloc->proj_out(TypeFunc::Parms);
assert (raw_result != NULL, "must have an allocation result");
for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
Node *use = raw_result->fast_out(i);
if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
Node* addp2 = find_second_addp(use, raw_result);
if (addp2 != NULL) {
assert(alloc->is_AllocateArray(),"array allocation was expected");
alloc_worklist.append_if_missing(addp2);
}
alloc_worklist.append_if_missing(use);
} else if (use->is_Initialize()) {
memnode_worklist.append_if_missing(use);
}
}
}
} else if (n->is_AddP()) {
ptset.Clear();
PointsTo(ptset, get_addp_base(n), igvn);
assert(ptset.Size() == 1, "AddP address is unique");
uint elem = ptset.getelem(); // Allocation node's index
if (elem == _phantom_object)
continue; // Assume the value was set outside this method.
Node *base = get_map(elem); // CheckCastPP node
if (!split_AddP(n, base, igvn)) continue; // wrong type
tinst = igvn->type(base)->isa_oopptr();
} else if (n->is_Phi() ||
n->is_CheckCastPP() ||
n->is_EncodeP() ||
n->is_DecodeN() ||
(n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
if (visited.test_set(n->_idx)) {
assert(n->is_Phi(), "loops only through Phi's");
continue; // already processed
}
ptset.Clear();
PointsTo(ptset, n, igvn);
if (ptset.Size() == 1) {
uint elem = ptset.getelem(); // Allocation node's index
if (elem == _phantom_object)
continue; // Assume the value was set outside this method.
Node *val = get_map(elem); // CheckCastPP node
TypeNode *tn = n->as_Type();
tinst = igvn->type(val)->isa_oopptr();
assert(tinst != NULL && tinst->is_known_instance() &&
(uint)tinst->instance_id() == elem , "instance type expected.");
const Type *tn_type = igvn->type(tn);
const TypeOopPtr *tn_t;
if (tn_type->isa_narrowoop()) {
tn_t = tn_type->make_ptr()->isa_oopptr();
} else {
tn_t = tn_type->isa_oopptr();
}
if (tn_t != NULL &&
tinst->cast_to_instance_id(TypeOopPtr::InstanceBot)->higher_equal(tn_t)) {
if (tn_type->isa_narrowoop()) {
tn_type = tinst->make_narrowoop();
} else {
tn_type = tinst;
}
igvn->hash_delete(tn);
igvn->set_type(tn, tn_type);
tn->set_type(tn_type);
igvn->hash_insert(tn);
record_for_optimizer(n);
} else {
continue; // wrong type
}
}
} else {
continue;
}
// push users on appropriate worklist
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node *use = n->fast_out(i);
if(use->is_Mem() && use->in(MemNode::Address) == n) {
memnode_worklist.append_if_missing(use);
} else if (use->is_Initialize()) {
memnode_worklist.append_if_missing(use);
} else if (use->is_MergeMem()) {
mergemem_worklist.append_if_missing(use);
} else if (use->is_SafePoint() && tinst != NULL) {
// Look for MergeMem nodes for calls which reference unique allocation
// (through CheckCastPP nodes) even for debug info.
Node* m = use->in(TypeFunc::Memory);
uint iid = tinst->instance_id();
while (m->is_Proj() && m->in(0)->is_SafePoint() &&
m->in(0) != use && !m->in(0)->_idx != iid) {
m = m->in(0)->in(TypeFunc::Memory);
}
if (m->is_MergeMem()) {
mergemem_worklist.append_if_missing(m);
}
} else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
Node* addp2 = find_second_addp(use, n);
if (addp2 != NULL) {
alloc_worklist.append_if_missing(addp2);
}
alloc_worklist.append_if_missing(use);
} else if (use->is_Phi() ||
use->is_CheckCastPP() ||
use->is_EncodeP() ||
use->is_DecodeN() ||
(use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
alloc_worklist.append_if_missing(use);
}
}
}
// New alias types were created in split_AddP().
uint new_index_end = (uint) _compile->num_alias_types();
// Phase 2: Process MemNode's from memnode_worklist. compute new address type and
// compute new values for Memory inputs (the Memory inputs are not
// actually updated until phase 4.)
if (memnode_worklist.length() == 0)
return; // nothing to do
while (memnode_worklist.length() != 0) {
Node *n = memnode_worklist.pop();
if (visited.test_set(n->_idx))
continue;
if (n->is_Phi()) {
assert(n->as_Phi()->adr_type() != TypePtr::BOTTOM, "narrow memory slice required");
// we don't need to do anything, but the users must be pushed if we haven't processed
// this Phi before
} else if (n->is_Initialize()) {
// we don't need to do anything, but the users of the memory projection must be pushed
n = n->as_Initialize()->proj_out(TypeFunc::Memory);
if (n == NULL)
continue;
} else {
assert(n->is_Mem(), "memory node required.");
Node *addr = n->in(MemNode::Address);
assert(addr->is_AddP(), "AddP required");
const Type *addr_t = igvn->type(addr);
if (addr_t == Type::TOP)
continue;
assert (addr_t->isa_ptr() != NULL, "pointer type required.");
int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
assert ((uint)alias_idx < new_index_end, "wrong alias index");
Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn);
if (_compile->failing()) {
return;
}
if (mem != n->in(MemNode::Memory)) {
set_map(n->_idx, mem);
ptnode_adr(n->_idx)->_node = n;
}
if (n->is_Load()) {
continue; // don't push users
} else if (n->is_LoadStore()) {
// get the memory projection
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node *use = n->fast_out(i);
if (use->Opcode() == Op_SCMemProj) {
n = use;
break;
}
}
assert(n->Opcode() == Op_SCMemProj, "memory projection required");
}
}
// push user on appropriate worklist
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node *use = n->fast_out(i);
if (use->is_Phi()) {
memnode_worklist.append_if_missing(use);
} else if(use->is_Mem() && use->in(MemNode::Memory) == n) {
memnode_worklist.append_if_missing(use);
} else if (use->is_Initialize()) {
memnode_worklist.append_if_missing(use);
} else if (use->is_MergeMem()) {
mergemem_worklist.append_if_missing(use);
}
}
}
// Phase 3: Process MergeMem nodes from mergemem_worklist.
// Walk each memory moving the first node encountered of each
// instance type to the the input corresponding to its alias index.
while (mergemem_worklist.length() != 0) {
Node *n = mergemem_worklist.pop();
assert(n->is_MergeMem(), "MergeMem node required.");
if (visited.test_set(n->_idx))
continue;
MergeMemNode *nmm = n->as_MergeMem();
// Note: we don't want to use MergeMemStream here because we only want to
// scan inputs which exist at the start, not ones we add during processing.
uint nslices = nmm->req();
igvn->hash_delete(nmm);
for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
Node* mem = nmm->in(i);
Node* cur = NULL;
if (mem == NULL || mem->is_top())
continue;
while (mem->is_Mem()) {
const Type *at = igvn->type(mem->in(MemNode::Address));
if (at != Type::TOP) {
assert (at->isa_ptr() != NULL, "pointer type required.");
uint idx = (uint)_compile->get_alias_index(at->is_ptr());
if (idx == i) {
if (cur == NULL)
cur = mem;
} else {
if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
nmm->set_memory_at(idx, mem);
}
}
}
mem = mem->in(MemNode::Memory);
}
nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
// Find any instance of the current type if we haven't encountered
// a value of the instance along the chain.
for (uint ni = new_index_start; ni < new_index_end; ni++) {
if((uint)_compile->get_general_index(ni) == i) {
Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
if (nmm->is_empty_memory(m)) {
Node* result = find_inst_mem(mem, ni, orig_phis, igvn);
if (_compile->failing()) {
return;
}
nmm->set_memory_at(ni, result);
}
}
}
}
// Find the rest of instances values
for (uint ni = new_index_start; ni < new_index_end; ni++) {
const TypeOopPtr *tinst = igvn->C->get_adr_type(ni)->isa_oopptr();
Node* result = step_through_mergemem(nmm, ni, tinst);
if (result == nmm->base_memory()) {
// Didn't find instance memory, search through general slice recursively.
result = nmm->memory_at(igvn->C->get_general_index(ni));
result = find_inst_mem(result, ni, orig_phis, igvn);
if (_compile->failing()) {
return;
}
nmm->set_memory_at(ni, result);
}
}
igvn->hash_insert(nmm);
record_for_optimizer(nmm);
// Propagate new memory slices to following MergeMem nodes.
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node *use = n->fast_out(i);
if (use->is_Call()) {
CallNode* in = use->as_Call();
if (in->proj_out(TypeFunc::Memory) != NULL) {
Node* m = in->proj_out(TypeFunc::Memory);
for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
Node* mm = m->fast_out(j);
if (mm->is_MergeMem()) {
mergemem_worklist.append_if_missing(mm);
}
}
}
if (use->is_Allocate()) {
use = use->as_Allocate()->initialization();
if (use == NULL) {
continue;
}
}
}
if (use->is_Initialize()) {
InitializeNode* in = use->as_Initialize();
if (in->proj_out(TypeFunc::Memory) != NULL) {
Node* m = in->proj_out(TypeFunc::Memory);
for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
Node* mm = m->fast_out(j);
if (mm->is_MergeMem()) {
mergemem_worklist.append_if_missing(mm);
}
}
}
}
}
}
// Phase 4: Update the inputs of non-instance memory Phis and
// the Memory input of memnodes
// First update the inputs of any non-instance Phi's from
// which we split out an instance Phi. Note we don't have
// to recursively process Phi's encounted on the input memory
// chains as is done in split_memory_phi() since they will
// also be processed here.
for (int j = 0; j < orig_phis.length(); j++) {
PhiNode *phi = orig_phis.at(j);
int alias_idx = _compile->get_alias_index(phi->adr_type());
igvn->hash_delete(phi);
for (uint i = 1; i < phi->req(); i++) {
Node *mem = phi->in(i);
Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn);
if (_compile->failing()) {
return;
}
if (mem != new_mem) {
phi->set_req(i, new_mem);
}
}
igvn->hash_insert(phi);
record_for_optimizer(phi);
}
// Update the memory inputs of MemNodes with the value we computed
// in Phase 2.
for (uint i = 0; i < nodes_size(); i++) {
Node *nmem = get_map(i);
if (nmem != NULL) {
Node *n = ptnode_adr(i)->_node;
if (n != NULL && n->is_Mem()) {
igvn->hash_delete(n);
n->set_req(MemNode::Memory, nmem);
igvn->hash_insert(n);
record_for_optimizer(n);
}
}
}
}
bool ConnectionGraph::has_candidates(Compile *C) {
// EA brings benefits only when the code has allocations and/or locks which
// are represented by ideal Macro nodes.
int cnt = C->macro_count();
for( int i=0; i < cnt; i++ ) {
Node *n = C->macro_node(i);
if ( n->is_Allocate() )
return true;
if( n->is_Lock() ) {
Node* obj = n->as_Lock()->obj_node()->uncast();
if( !(obj->is_Parm() || obj->is_Con()) )
return true;
}
}
return false;
}
bool ConnectionGraph::compute_escape() {
Compile* C = _compile;
// 1. Populate Connection Graph (CG) with Ideal nodes.
Unique_Node_List worklist_init;
worklist_init.map(C->unique(), NULL); // preallocate space
// Initialize worklist
if (C->root() != NULL) {
worklist_init.push(C->root());
}
GrowableArray<int> cg_worklist;
PhaseGVN* igvn = C->initial_gvn();
bool has_allocations = false;
// Push all useful nodes onto CG list and set their type.
for( uint next = 0; next < worklist_init.size(); ++next ) {
Node* n = worklist_init.at(next);
record_for_escape_analysis(n, igvn);
// Only allocations and java static calls results are checked
// for an escape status. See process_call_result() below.
if (n->is_Allocate() || n->is_CallStaticJava() &&
ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) {
has_allocations = true;
}
if(n->is_AddP())
cg_worklist.append(n->_idx);
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node* m = n->fast_out(i); // Get user
worklist_init.push(m);
}
}
if (!has_allocations) {
_collecting = false;
return false; // Nothing to do.
}
// 2. First pass to create simple CG edges (doesn't require to walk CG).
uint delayed_size = _delayed_worklist.size();
for( uint next = 0; next < delayed_size; ++next ) {
Node* n = _delayed_worklist.at(next);
build_connection_graph(n, igvn);
}
// 3. Pass to create fields edges (Allocate -F-> AddP).
uint cg_length = cg_worklist.length();
for( uint next = 0; next < cg_length; ++next ) {
int ni = cg_worklist.at(next);
build_connection_graph(ptnode_adr(ni)->_node, igvn);
}
cg_worklist.clear();
cg_worklist.append(_phantom_object);
// 4. Build Connection Graph which need
// to walk the connection graph.
for (uint ni = 0; ni < nodes_size(); ni++) {
PointsToNode* ptn = ptnode_adr(ni);
Node *n = ptn->_node;
if (n != NULL) { // Call, AddP, LoadP, StoreP
build_connection_graph(n, igvn);
if (ptn->node_type() != PointsToNode::UnknownType)
cg_worklist.append(n->_idx); // Collect CG nodes
}
}
VectorSet ptset(Thread::current()->resource_area());
GrowableArray<uint> deferred_edges;
VectorSet visited(Thread::current()->resource_area());
// 5. Remove deferred edges from the graph and collect
// information needed for type splitting.
cg_length = cg_worklist.length();
for( uint next = 0; next < cg_length; ++next ) {
int ni = cg_worklist.at(next);
PointsToNode* ptn = ptnode_adr(ni);
PointsToNode::NodeType nt = ptn->node_type();
if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) {
remove_deferred(ni, &deferred_edges, &visited);
Node *n = ptn->_node;
if (n->is_AddP()) {
// Search for objects which are not scalar replaceable.
// Mark their escape state as ArgEscape to propagate the state
// to referenced objects.
// Note: currently there are no difference in compiler optimizations
// for ArgEscape objects and NoEscape objects which are not
// scalar replaceable.
int offset = ptn->offset();
Node *base = get_addp_base(n);
ptset.Clear();
PointsTo(ptset, base, igvn);
int ptset_size = ptset.Size();
// Check if a field's initializing value is recorded and add
// a corresponding NULL field's value if it is not recorded.
// Connection Graph does not record a default initialization by NULL
// captured by Initialize node.
//
// Note: it will disable scalar replacement in some cases:
//
// Point p[] = new Point[1];
// p[0] = new Point(); // Will be not scalar replaced
//
// but it will save us from incorrect optimizations in next cases:
//
// Point p[] = new Point[1];
// if ( x ) p[0] = new Point(); // Will be not scalar replaced
//
// Without a control flow analysis we can't distinguish above cases.
//
if (offset != Type::OffsetBot && ptset_size == 1) {
uint elem = ptset.getelem(); // Allocation node's index
// It does not matter if it is not Allocation node since
// only non-escaping allocations are scalar replaced.
if (ptnode_adr(elem)->_node->is_Allocate() &&
ptnode_adr(elem)->escape_state() == PointsToNode::NoEscape) {
AllocateNode* alloc = ptnode_adr(elem)->_node->as_Allocate();
InitializeNode* ini = alloc->initialization();
Node* value = NULL;
if (ini != NULL) {
BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT;
Node* store = ini->find_captured_store(offset, type2aelembytes(ft), igvn);
if (store != NULL && store->is_Store())
value = store->in(MemNode::ValueIn);
}
if (value == NULL || value != ptnode_adr(value->_idx)->_node) {
// A field's initializing value was not recorded. Add NULL.
uint null_idx = UseCompressedOops ? _noop_null : _oop_null;
add_pointsto_edge(ni, null_idx);
}
}
}
// An object is not scalar replaceable if the field which may point
// to it has unknown offset (unknown element of an array of objects).
//
if (offset == Type::OffsetBot) {
uint e_cnt = ptn->edge_count();
for (uint ei = 0; ei < e_cnt; ei++) {
uint npi = ptn->edge_target(ei);
set_escape_state(npi, PointsToNode::ArgEscape);
ptnode_adr(npi)->_scalar_replaceable = false;
}
}
// Currently an object is not scalar replaceable if a LoadStore node
// access its field since the field value is unknown after it.
//
bool has_LoadStore = false;
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
Node *use = n->fast_out(i);
if (use->is_LoadStore()) {
has_LoadStore = true;
break;
}
}
// An object is not scalar replaceable if the address points
// to unknown field (unknown element for arrays, offset is OffsetBot).
//
// Or the address may point to more then one object. This may produce
// the false positive result (set scalar_replaceable to false)
// since the flow-insensitive escape analysis can't separate
// the case when stores overwrite the field's value from the case
// when stores happened on different control branches.
//
if (ptset_size > 1 || ptset_size != 0 &&
(has_LoadStore || offset == Type::OffsetBot)) {
for( VectorSetI j(&ptset); j.test(); ++j ) {
set_escape_state(j.elem, PointsToNode::ArgEscape);
ptnode_adr(j.elem)->_scalar_replaceable = false;
}
}
}
}
}
// 6. Propagate escape states.
GrowableArray<int> worklist;
bool has_non_escaping_obj = false;
// push all GlobalEscape nodes on the worklist
for( uint next = 0; next < cg_length; ++next ) {
int nk = cg_worklist.at(next);
if (ptnode_adr(nk)->escape_state() == PointsToNode::GlobalEscape)
worklist.push(nk);
}
// mark all nodes reachable from GlobalEscape nodes
while(worklist.length() > 0) {
PointsToNode* ptn = ptnode_adr(worklist.pop());
uint e_cnt = ptn->edge_count();
for (uint ei = 0; ei < e_cnt; ei++) {
uint npi = ptn->edge_target(ei);
PointsToNode *np = ptnode_adr(npi);
if (np->escape_state() < PointsToNode::GlobalEscape) {
np->set_escape_state(PointsToNode::GlobalEscape);
worklist.push(npi);
}
}
}
// push all ArgEscape nodes on the worklist
for( uint next = 0; next < cg_length; ++next ) {
int nk = cg_worklist.at(next);
if (ptnode_adr(nk)->escape_state() == PointsToNode::ArgEscape)
worklist.push(nk);
}
// mark all nodes reachable from ArgEscape nodes
while(worklist.length() > 0) {
PointsToNode* ptn = ptnode_adr(worklist.pop());
if (ptn->node_type() == PointsToNode::JavaObject)
has_non_escaping_obj = true; // Non GlobalEscape
uint e_cnt = ptn->edge_count();
for (uint ei = 0; ei < e_cnt; ei++) {
uint npi = ptn->edge_target(ei);
PointsToNode *np = ptnode_adr(npi);
if (np->escape_state() < PointsToNode::ArgEscape) {
np->set_escape_state(PointsToNode::ArgEscape);
worklist.push(npi);
}
}
}
GrowableArray<Node*> alloc_worklist;
// push all NoEscape nodes on the worklist
for( uint next = 0; next < cg_length; ++next ) {
int nk = cg_worklist.at(next);
if (ptnode_adr(nk)->escape_state() == PointsToNode::NoEscape)
worklist.push(nk);
}
// mark all nodes reachable from NoEscape nodes
while(worklist.length() > 0) {
PointsToNode* ptn = ptnode_adr(worklist.pop());
if (ptn->node_type() == PointsToNode::JavaObject)
has_non_escaping_obj = true; // Non GlobalEscape
Node* n = ptn->_node;
if (n->is_Allocate() && ptn->_scalar_replaceable ) {
// Push scalar replaceable allocations on alloc_worklist
// for processing in split_unique_types().
alloc_worklist.append(n);
}
uint e_cnt = ptn->edge_count();
for (uint ei = 0; ei < e_cnt; ei++) {
uint npi = ptn->edge_target(ei);
PointsToNode *np = ptnode_adr(npi);
if (np->escape_state() < PointsToNode::NoEscape) {
np->set_escape_state(PointsToNode::NoEscape);
worklist.push(npi);
}
}
}
_collecting = false;
assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build");
bool has_scalar_replaceable_candidates = alloc_worklist.length() > 0;
if ( has_scalar_replaceable_candidates &&
C->AliasLevel() >= 3 && EliminateAllocations ) {
// Now use the escape information to create unique types for
// scalar replaceable objects.
split_unique_types(alloc_worklist);
if (C->failing()) return false;
// Clean up after split unique types.
ResourceMark rm;
PhaseRemoveUseless pru(C->initial_gvn(), C->for_igvn());
C->print_method("After Escape Analysis", 2);
#ifdef ASSERT
} else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
tty->print("=== No allocations eliminated for ");
C->method()->print_short_name();
if(!EliminateAllocations) {
tty->print(" since EliminateAllocations is off ===");
} else if(!has_scalar_replaceable_candidates) {
tty->print(" since there are no scalar replaceable candidates ===");
} else if(C->AliasLevel() < 3) {
tty->print(" since AliasLevel < 3 ===");
}
tty->cr();
#endif
}
return has_non_escaping_obj;
}
void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) {
switch (call->Opcode()) {
#ifdef ASSERT
case Op_Allocate:
case Op_AllocateArray:
case Op_Lock:
case Op_Unlock:
assert(false, "should be done already");
break;
#endif
case Op_CallLeafNoFP:
{
// Stub calls, objects do not escape but they are not scale replaceable.
// Adjust escape state for outgoing arguments.
const TypeTuple * d = call->tf()->domain();
VectorSet ptset(Thread::current()->resource_area());
for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
const Type* at = d->field_at(i);
Node *arg = call->in(i)->uncast();
const Type *aat = phase->type(arg);
if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr()) {
assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
aat->isa_ptr() != NULL, "expecting an Ptr");
set_escape_state(arg->_idx, PointsToNode::ArgEscape);
if (arg->is_AddP()) {
//
// The inline_native_clone() case when the arraycopy stub is called
// after the allocation before Initialize and CheckCastPP nodes.
//
// Set AddP's base (Allocate) as not scalar replaceable since
// pointer to the base (with offset) is passed as argument.
//
arg = get_addp_base(arg);
}
ptset.Clear();
PointsTo(ptset, arg, phase);
for( VectorSetI j(&ptset); j.test(); ++j ) {
uint pt = j.elem;
set_escape_state(pt, PointsToNode::ArgEscape);
}
}
}
break;
}
case Op_CallStaticJava:
// For a static call, we know exactly what method is being called.
// Use bytecode estimator to record the call's escape affects
{
ciMethod *meth = call->as_CallJava()->method();
BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
// fall-through if not a Java method or no analyzer information
if (call_analyzer != NULL) {
const TypeTuple * d = call->tf()->domain();
VectorSet ptset(Thread::current()->resource_area());
bool copy_dependencies = false;
for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
const Type* at = d->field_at(i);
int k = i - TypeFunc::Parms;
if (at->isa_oopptr() != NULL) {
Node *arg = call->in(i)->uncast();
bool global_escapes = false;
bool fields_escapes = false;
if (!call_analyzer->is_arg_stack(k)) {
// The argument global escapes, mark everything it could point to
set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
global_escapes = true;
} else {
if (!call_analyzer->is_arg_local(k)) {
// The argument itself doesn't escape, but any fields might
fields_escapes = true;
}
set_escape_state(arg->_idx, PointsToNode::ArgEscape);
copy_dependencies = true;
}
ptset.Clear();
PointsTo(ptset, arg, phase);
for( VectorSetI j(&ptset); j.test(); ++j ) {
uint pt = j.elem;
if (global_escapes) {
//The argument global escapes, mark everything it could point to
set_escape_state(pt, PointsToNode::GlobalEscape);
} else {
if (fields_escapes) {
// The argument itself doesn't escape, but any fields might
add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
}
set_escape_state(pt, PointsToNode::ArgEscape);
}
}
}
}
if (copy_dependencies)
call_analyzer->copy_dependencies(_compile->dependencies());
break;
}
}
default:
// Fall-through here if not a Java method or no analyzer information
// or some other type of call, assume the worst case: all arguments
// globally escape.
{
// adjust escape state for outgoing arguments
const TypeTuple * d = call->tf()->domain();
VectorSet ptset(Thread::current()->resource_area());
for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
const Type* at = d->field_at(i);
if (at->isa_oopptr() != NULL) {
Node *arg = call->in(i)->uncast();
set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
ptset.Clear();
PointsTo(ptset, arg, phase);
for( VectorSetI j(&ptset); j.test(); ++j ) {
uint pt = j.elem;
set_escape_state(pt, PointsToNode::GlobalEscape);
}
}
}
}
}
}
void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) {
CallNode *call = resproj->in(0)->as_Call();
uint call_idx = call->_idx;
uint resproj_idx = resproj->_idx;
switch (call->Opcode()) {
case Op_Allocate:
{
Node *k = call->in(AllocateNode::KlassNode);
const TypeKlassPtr *kt;
if (k->Opcode() == Op_LoadKlass) {
kt = k->as_Load()->type()->isa_klassptr();
} else {
// Also works for DecodeN(LoadNKlass).
kt = k->as_Type()->type()->isa_klassptr();
}
assert(kt != NULL, "TypeKlassPtr required.");
ciKlass* cik = kt->klass();
ciInstanceKlass* ciik = cik->as_instance_klass();
PointsToNode::EscapeState es;
uint edge_to;
if (cik->is_subclass_of(_compile->env()->Thread_klass()) || ciik->has_finalizer()) {
es = PointsToNode::GlobalEscape;
edge_to = _phantom_object; // Could not be worse
} else {
es = PointsToNode::NoEscape;
edge_to = call_idx;
}
set_escape_state(call_idx, es);
add_pointsto_edge(resproj_idx, edge_to);
_processed.set(resproj_idx);
break;
}
case Op_AllocateArray:
{
int length = call->in(AllocateNode::ALength)->find_int_con(-1);
if (length < 0 || length > EliminateAllocationArraySizeLimit) {
// Not scalar replaceable if the length is not constant or too big.
ptnode_adr(call_idx)->_scalar_replaceable = false;
}
set_escape_state(call_idx, PointsToNode::NoEscape);
add_pointsto_edge(resproj_idx, call_idx);
_processed.set(resproj_idx);
break;
}
case Op_CallStaticJava:
// For a static call, we know exactly what method is being called.
// Use bytecode estimator to record whether the call's return value escapes
{
bool done = true;
const TypeTuple *r = call->tf()->range();
const Type* ret_type = NULL;
if (r->cnt() > TypeFunc::Parms)
ret_type = r->field_at(TypeFunc::Parms);
// Note: we use isa_ptr() instead of isa_oopptr() here because the
// _multianewarray functions return a TypeRawPtr.
if (ret_type == NULL || ret_type->isa_ptr() == NULL) {
_processed.set(resproj_idx);
break; // doesn't return a pointer type
}
ciMethod *meth = call->as_CallJava()->method();
const TypeTuple * d = call->tf()->domain();
if (meth == NULL) {
// not a Java method, assume global escape
set_escape_state(call_idx, PointsToNode::GlobalEscape);
add_pointsto_edge(resproj_idx, _phantom_object);
} else {
BCEscapeAnalyzer *call_analyzer = meth->get_bcea();
bool copy_dependencies = false;
if (call_analyzer->is_return_allocated()) {
// Returns a newly allocated unescaped object, simply
// update dependency information.
// Mark it as NoEscape so that objects referenced by
// it's fields will be marked as NoEscape at least.
set_escape_state(call_idx, PointsToNode::NoEscape);
add_pointsto_edge(resproj_idx, call_idx);
copy_dependencies = true;
} else if (call_analyzer->is_return_local()) {
// determine whether any arguments are returned
set_escape_state(call_idx, PointsToNode::NoEscape);
bool ret_arg = false;
for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
const Type* at = d->field_at(i);
if (at->isa_oopptr() != NULL) {
Node *arg = call->in(i)->uncast();
if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
ret_arg = true;
PointsToNode *arg_esp = ptnode_adr(arg->_idx);
if (arg_esp->node_type() == PointsToNode::UnknownType)
done = false;
else if (arg_esp->node_type() == PointsToNode::JavaObject)
add_pointsto_edge(resproj_idx, arg->_idx);
else
add_deferred_edge(resproj_idx, arg->_idx);
arg_esp->_hidden_alias = true;
}
}
}
if (done && !ret_arg) {
// Returns unknown object.
set_escape_state(call_idx, PointsToNode::GlobalEscape);
add_pointsto_edge(resproj_idx, _phantom_object);
}
copy_dependencies = true;
} else {
set_escape_state(call_idx, PointsToNode::GlobalEscape);
add_pointsto_edge(resproj_idx, _phantom_object);
for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
const Type* at = d->field_at(i);
if (at->isa_oopptr() != NULL) {
Node *arg = call->in(i)->uncast();
PointsToNode *arg_esp = ptnode_adr(arg->_idx);
arg_esp->_hidden_alias = true;
}
}
}
if (copy_dependencies)
call_analyzer->copy_dependencies(_compile->dependencies());
}
if (done)
_processed.set(resproj_idx);
break;
}
default:
// Some other type of call, assume the worst case that the
// returned value, if any, globally escapes.
{
const TypeTuple *r = call->tf()->range();
if (r->cnt() > TypeFunc::Parms) {
const Type* ret_type = r->field_at(TypeFunc::Parms);
// Note: we use isa_ptr() instead of isa_oopptr() here because the
// _multianewarray functions return a TypeRawPtr.
if (ret_type->isa_ptr() != NULL) {
set_escape_state(call_idx, PointsToNode::GlobalEscape);
add_pointsto_edge(resproj_idx, _phantom_object);
}
}
_processed.set(resproj_idx);
}
}
}
// Populate Connection Graph with Ideal nodes and create simple
// connection graph edges (do not need to check the node_type of inputs
// or to call PointsTo() to walk the connection graph).
void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) {
if (_processed.test(n->_idx))
return; // No need to redefine node's state.
if (n->is_Call()) {
// Arguments to allocation and locking don't escape.
if (n->is_Allocate()) {
add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true);
record_for_optimizer(n);
} else if (n->is_Lock() || n->is_Unlock()) {
// Put Lock and Unlock nodes on IGVN worklist to process them during
// the first IGVN optimization when escape information is still available.
record_for_optimizer(n);
_processed.set(n->_idx);
} else {
// Have to process call's arguments first.
PointsToNode::NodeType nt = PointsToNode::UnknownType;
// Check if a call returns an object.
const TypeTuple *r = n->as_Call()->tf()->range();
if (n->is_CallStaticJava() && r->cnt() > TypeFunc::Parms &&
n->as_Call()->proj_out(TypeFunc::Parms) != NULL) {
// Note: use isa_ptr() instead of isa_oopptr() here because
// the _multianewarray functions return a TypeRawPtr.
if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
nt = PointsToNode::JavaObject;
}
}
add_node(n, nt, PointsToNode::UnknownEscape, false);
}
return;
}
// Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
// ThreadLocal has RawPrt type.
switch (n->Opcode()) {
case Op_AddP:
{
add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false);
break;
}
case Op_CastX2P:
{ // "Unsafe" memory access.
add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
break;
}
case Op_CastPP:
case Op_CheckCastPP:
case Op_EncodeP:
case Op_DecodeN:
{
add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
int ti = n->in(1)->_idx;
PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
if (nt == PointsToNode::UnknownType) {
_delayed_worklist.push(n); // Process it later.
break;
} else if (nt == PointsToNode::JavaObject) {
add_pointsto_edge(n->_idx, ti);
} else {
add_deferred_edge(n->_idx, ti);
}
_processed.set(n->_idx);
break;
}
case Op_ConP:
{
// assume all pointer constants globally escape except for null
PointsToNode::EscapeState es;
if (phase->type(n) == TypePtr::NULL_PTR)
es = PointsToNode::NoEscape;
else
es = PointsToNode::GlobalEscape;
add_node(n, PointsToNode::JavaObject, es, true);
break;
}
case Op_ConN:
{
// assume all narrow oop constants globally escape except for null
PointsToNode::EscapeState es;
if (phase->type(n) == TypeNarrowOop::NULL_PTR)
es = PointsToNode::NoEscape;
else
es = PointsToNode::GlobalEscape;
add_node(n, PointsToNode::JavaObject, es, true);
break;
}
case Op_CreateEx:
{
// assume that all exception objects globally escape
add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
break;
}
case Op_LoadKlass:
case Op_LoadNKlass:
{
add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
break;
}
case Op_LoadP:
case Op_LoadN:
{
const Type *t = phase->type(n);
if (t->make_ptr() == NULL) {
_processed.set(n->_idx);
return;
}
add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
break;
}
case Op_Parm:
{
_processed.set(n->_idx); // No need to redefine it state.
uint con = n->as_Proj()->_con;
if (con < TypeFunc::Parms)
return;
const Type *t = n->in(0)->as_Start()->_domain->field_at(con);
if (t->isa_ptr() == NULL)
return;
// We have to assume all input parameters globally escape
// (Note: passing 'false' since _processed is already set).
add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false);
break;
}
case Op_Phi:
{
const Type *t = n->as_Phi()->type();
if (t->make_ptr() == NULL) {
// nothing to do if not an oop or narrow oop
_processed.set(n->_idx);
return;
}
add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
uint i;
for (i = 1; i < n->req() ; i++) {
Node* in = n->in(i);
if (in == NULL)
continue; // ignore NULL
in = in->uncast();
if (in->is_top() || in == n)
continue; // ignore top or inputs which go back this node
int ti = in->_idx;
PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
if (nt == PointsToNode::UnknownType) {
break;
} else if (nt == PointsToNode::JavaObject) {
add_pointsto_edge(n->_idx, ti);
} else {
add_deferred_edge(n->_idx, ti);
}
}
if (i >= n->req())
_processed.set(n->_idx);
else
_delayed_worklist.push(n);
break;
}
case Op_Proj:
{
// we are only interested in the result projection from a call
if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
process_call_result(n->as_Proj(), phase);
if (!_processed.test(n->_idx)) {
// The call's result may need to be processed later if the call
// returns it's argument and the argument is not processed yet.
_delayed_worklist.push(n);
}
} else {
_processed.set(n->_idx);
}
break;
}
case Op_Return:
{
if( n->req() > TypeFunc::Parms &&
phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
// Treat Return value as LocalVar with GlobalEscape escape state.
add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false);
int ti = n->in(TypeFunc::Parms)->_idx;
PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
if (nt == PointsToNode::UnknownType) {
_delayed_worklist.push(n); // Process it later.
break;
} else if (nt == PointsToNode::JavaObject) {
add_pointsto_edge(n->_idx, ti);
} else {
add_deferred_edge(n->_idx, ti);
}
}
_processed.set(n->_idx);
break;
}
case Op_StoreP:
case Op_StoreN:
{
const Type *adr_type = phase->type(n->in(MemNode::Address));
adr_type = adr_type->make_ptr();
if (adr_type->isa_oopptr()) {
add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
} else {
Node* adr = n->in(MemNode::Address);
if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL &&
adr->in(AddPNode::Address)->is_Proj() &&
adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
// We are computing a raw address for a store captured
// by an Initialize compute an appropriate address type.
int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
assert(offs != Type::OffsetBot, "offset must be a constant");
} else {
_processed.set(n->_idx);
return;
}
}
break;
}
case Op_StorePConditional:
case Op_CompareAndSwapP:
case Op_CompareAndSwapN:
{
const Type *adr_type = phase->type(n->in(MemNode::Address));
adr_type = adr_type->make_ptr();
if (adr_type->isa_oopptr()) {
add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
} else {
_processed.set(n->_idx);
return;
}
break;
}
case Op_ThreadLocal:
{
add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true);
break;
}
default:
;
// nothing to do
}
return;
}
void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) {
uint n_idx = n->_idx;
// Don't set processed bit for AddP, LoadP, StoreP since
// they may need more then one pass to process.
if (_processed.test(n_idx))
return; // No need to redefine node's state.
if (n->is_Call()) {
CallNode *call = n->as_Call();
process_call_arguments(call, phase);
_processed.set(n_idx);
return;
}
switch (n->Opcode()) {
case Op_AddP:
{
Node *base = get_addp_base(n);
// Create a field edge to this node from everything base could point to.
VectorSet ptset(Thread::current()->resource_area());
PointsTo(ptset, base, phase);
for( VectorSetI i(&ptset); i.test(); ++i ) {
uint pt = i.elem;
add_field_edge(pt, n_idx, address_offset(n, phase));
}
break;
}
case Op_CastX2P:
{
assert(false, "Op_CastX2P");
break;
}
case Op_CastPP:
case Op_CheckCastPP:
case Op_EncodeP:
case Op_DecodeN:
{
int ti = n->in(1)->_idx;
if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
add_pointsto_edge(n_idx, ti);
} else {
add_deferred_edge(n_idx, ti);
}
_processed.set(n_idx);
break;
}
case Op_ConP:
{
assert(false, "Op_ConP");
break;
}
case Op_ConN:
{
assert(false, "Op_ConN");
break;
}
case Op_CreateEx:
{
assert(false, "Op_CreateEx");
break;
}
case Op_LoadKlass:
case Op_LoadNKlass:
{
assert(false, "Op_LoadKlass");
break;
}
case Op_LoadP:
case Op_LoadN:
{
const Type *t = phase->type(n);
#ifdef ASSERT
if (t->make_ptr() == NULL)
assert(false, "Op_LoadP");
#endif
Node* adr = n->in(MemNode::Address)->uncast();
const Type *adr_type = phase->type(adr);
Node* adr_base;
if (adr->is_AddP()) {
adr_base = get_addp_base(adr);
} else {
adr_base = adr;
}
// For everything "adr_base" could point to, create a deferred edge from
// this node to each field with the same offset.
VectorSet ptset(Thread::current()->resource_area());
PointsTo(ptset, adr_base, phase);
int offset = address_offset(adr, phase);
for( VectorSetI i(&ptset); i.test(); ++i ) {
uint pt = i.elem;
add_deferred_edge_to_fields(n_idx, pt, offset);
}
break;
}
case Op_Parm:
{
assert(false, "Op_Parm");
break;
}
case Op_Phi:
{
#ifdef ASSERT
const Type *t = n->as_Phi()->type();
if (t->make_ptr() == NULL)
assert(false, "Op_Phi");
#endif
for (uint i = 1; i < n->req() ; i++) {
Node* in = n->in(i);
if (in == NULL)
continue; // ignore NULL
in = in->uncast();
if (in->is_top() || in == n)
continue; // ignore top or inputs which go back this node
int ti = in->_idx;
PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
assert(nt != PointsToNode::UnknownType, "all nodes should be known");
if (nt == PointsToNode::JavaObject) {
add_pointsto_edge(n_idx, ti);
} else {
add_deferred_edge(n_idx, ti);
}
}
_processed.set(n_idx);
break;
}
case Op_Proj:
{
// we are only interested in the result projection from a call
if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
process_call_result(n->as_Proj(), phase);
assert(_processed.test(n_idx), "all call results should be processed");
} else {
assert(false, "Op_Proj");
}
break;
}
case Op_Return:
{
#ifdef ASSERT
if( n->req() <= TypeFunc::Parms ||
!phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
assert(false, "Op_Return");
}
#endif
int ti = n->in(TypeFunc::Parms)->_idx;
if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
add_pointsto_edge(n_idx, ti);
} else {
add_deferred_edge(n_idx, ti);
}
_processed.set(n_idx);
break;
}
case Op_StoreP:
case Op_StoreN:
case Op_StorePConditional:
case Op_CompareAndSwapP:
case Op_CompareAndSwapN:
{
Node *adr = n->in(MemNode::Address);
const Type *adr_type = phase->type(adr)->make_ptr();
#ifdef ASSERT
if (!adr_type->isa_oopptr())
assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP");
#endif
assert(adr->is_AddP(), "expecting an AddP");
Node *adr_base = get_addp_base(adr);
Node *val = n->in(MemNode::ValueIn)->uncast();
// For everything "adr_base" could point to, create a deferred edge
// to "val" from each field with the same offset.
VectorSet ptset(Thread::current()->resource_area());
PointsTo(ptset, adr_base, phase);
for( VectorSetI i(&ptset); i.test(); ++i ) {
uint pt = i.elem;
add_edge_from_fields(pt, val->_idx, address_offset(adr, phase));
}
break;
}
case Op_ThreadLocal:
{
assert(false, "Op_ThreadLocal");
break;
}
default:
;
// nothing to do
}
}
#ifndef PRODUCT
void ConnectionGraph::dump() {
PhaseGVN *igvn = _compile->initial_gvn();
bool first = true;
uint size = nodes_size();
for (uint ni = 0; ni < size; ni++) {
PointsToNode *ptn = ptnode_adr(ni);
PointsToNode::NodeType ptn_type = ptn->node_type();
if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL)
continue;
PointsToNode::EscapeState es = escape_state(ptn->_node, igvn);
if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) {
if (first) {
tty->cr();
tty->print("======== Connection graph for ");
_compile->method()->print_short_name();
tty->cr();
first = false;
}
tty->print("%6d ", ni);
ptn->dump();
// Print all locals which reference this allocation
for (uint li = ni; li < size; li++) {
PointsToNode *ptn_loc = ptnode_adr(li);
PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type();
if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL &&
ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) {
ptnode_adr(li)->dump(false);
}
}
if (Verbose) {
// Print all fields which reference this allocation
for (uint i = 0; i < ptn->edge_count(); i++) {
uint ei = ptn->edge_target(i);
ptnode_adr(ei)->dump(false);
}
}
tty->cr();
}
}
}
#endif