--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/opto/stringopts.cpp Thu Nov 12 09:24:21 2009 -0800
@@ -0,0 +1,1395 @@
+/*
+ * Copyright 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/_stringopts.cpp.incl"
+
+#define __ kit.
+
+class StringConcat : public ResourceObj {
+ private:
+ PhaseStringOpts* _stringopts;
+ Node* _string_alloc;
+ AllocateNode* _begin; // The allocation the begins the pattern
+ CallStaticJavaNode* _end; // The final call of the pattern. Will either be
+ // SB.toString or or String.<init>(SB.toString)
+ bool _multiple; // indicates this is a fusion of two or more
+ // separate StringBuilders
+
+ Node* _arguments; // The list of arguments to be concatenated
+ GrowableArray<int> _mode; // into a String along with a mode flag
+ // indicating how to treat the value.
+
+ Node_List _control; // List of control nodes that will be deleted
+ Node_List _uncommon_traps; // Uncommon traps that needs to be rewritten
+ // to restart at the initial JVMState.
+ public:
+ // Mode for converting arguments to Strings
+ enum {
+ StringMode,
+ IntMode,
+ CharMode
+ };
+
+ StringConcat(PhaseStringOpts* stringopts, CallStaticJavaNode* end):
+ _end(end),
+ _begin(NULL),
+ _multiple(false),
+ _string_alloc(NULL),
+ _stringopts(stringopts) {
+ _arguments = new (_stringopts->C, 1) Node(1);
+ _arguments->del_req(0);
+ }
+
+ bool validate_control_flow();
+
+ void merge_add() {
+#if 0
+ // XXX This is place holder code for reusing an existing String
+ // allocation but the logic for checking the state safety is
+ // probably inadequate at the moment.
+ CallProjections endprojs;
+ sc->end()->extract_projections(&endprojs, false);
+ if (endprojs.resproj != NULL) {
+ for (SimpleDUIterator i(endprojs.resproj); i.has_next(); i.next()) {
+ CallStaticJavaNode *use = i.get()->isa_CallStaticJava();
+ if (use != NULL && use->method() != NULL &&
+ use->method()->holder() == C->env()->String_klass() &&
+ use->method()->name() == ciSymbol::object_initializer_name() &&
+ use->in(TypeFunc::Parms + 1) == endprojs.resproj) {
+ // Found useless new String(sb.toString()) so reuse the newly allocated String
+ // when creating the result instead of allocating a new one.
+ sc->set_string_alloc(use->in(TypeFunc::Parms));
+ sc->set_end(use);
+ }
+ }
+ }
+#endif
+ }
+
+ StringConcat* merge(StringConcat* other, Node* arg);
+
+ void set_allocation(AllocateNode* alloc) {
+ _begin = alloc;
+ }
+
+ void append(Node* value, int mode) {
+ _arguments->add_req(value);
+ _mode.append(mode);
+ }
+ void push(Node* value, int mode) {
+ _arguments->ins_req(0, value);
+ _mode.insert_before(0, mode);
+ }
+ void push_string(Node* value) {
+ push(value, StringMode);
+ }
+ void push_int(Node* value) {
+ push(value, IntMode);
+ }
+ void push_char(Node* value) {
+ push(value, CharMode);
+ }
+
+ Node* argument(int i) {
+ return _arguments->in(i);
+ }
+ void set_argument(int i, Node* value) {
+ _arguments->set_req(i, value);
+ }
+ int num_arguments() {
+ return _mode.length();
+ }
+ int mode(int i) {
+ return _mode.at(i);
+ }
+ void add_control(Node* ctrl) {
+ assert(!_control.contains(ctrl), "only push once");
+ _control.push(ctrl);
+ }
+ CallStaticJavaNode* end() { return _end; }
+ AllocateNode* begin() { return _begin; }
+ Node* string_alloc() { return _string_alloc; }
+
+ void eliminate_unneeded_control();
+ void eliminate_initialize(InitializeNode* init);
+ void eliminate_call(CallNode* call);
+
+ void maybe_log_transform() {
+ CompileLog* log = _stringopts->C->log();
+ if (log != NULL) {
+ log->head("replace_string_concat arguments='%d' string_alloc='%d' multiple='%d'",
+ num_arguments(),
+ _string_alloc != NULL,
+ _multiple);
+ JVMState* p = _begin->jvms();
+ while (p != NULL) {
+ log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
+ p = p->caller();
+ }
+ log->tail("replace_string_concat");
+ }
+ }
+
+ void convert_uncommon_traps(GraphKit& kit, const JVMState* jvms) {
+ for (uint u = 0; u < _uncommon_traps.size(); u++) {
+ Node* uct = _uncommon_traps.at(u);
+
+ // Build a new call using the jvms state of the allocate
+ address call_addr = SharedRuntime::uncommon_trap_blob()->instructions_begin();
+ const TypeFunc* call_type = OptoRuntime::uncommon_trap_Type();
+ int size = call_type->domain()->cnt();
+ const TypePtr* no_memory_effects = NULL;
+ Compile* C = _stringopts->C;
+ CallStaticJavaNode* call = new (C, size) CallStaticJavaNode(call_type, call_addr, "uncommon_trap",
+ jvms->bci(), no_memory_effects);
+ for (int e = 0; e < TypeFunc::Parms; e++) {
+ call->init_req(e, uct->in(e));
+ }
+ // Set the trap request to record intrinsic failure if this trap
+ // is taken too many times. Ideally we would handle then traps by
+ // doing the original bookkeeping in the MDO so that if it caused
+ // the code to be thrown out we could still recompile and use the
+ // optimization. Failing the uncommon traps doesn't really mean
+ // that the optimization is a bad idea but there's no other way to
+ // do the MDO updates currently.
+ int trap_request = Deoptimization::make_trap_request(Deoptimization::Reason_intrinsic,
+ Deoptimization::Action_make_not_entrant);
+ call->init_req(TypeFunc::Parms, __ intcon(trap_request));
+ kit.add_safepoint_edges(call);
+
+ _stringopts->gvn()->transform(call);
+ C->gvn_replace_by(uct, call);
+ uct->disconnect_inputs(NULL);
+ }
+ }
+
+ void cleanup() {
+ // disconnect the hook node
+ _arguments->disconnect_inputs(NULL);
+ }
+};
+
+
+void StringConcat::eliminate_unneeded_control() {
+ eliminate_initialize(begin()->initialization());
+ for (uint i = 0; i < _control.size(); i++) {
+ Node* n = _control.at(i);
+ if (n->is_Call()) {
+ if (n != _end) {
+ eliminate_call(n->as_Call());
+ }
+ } else if (n->is_IfTrue()) {
+ Compile* C = _stringopts->C;
+ C->gvn_replace_by(n, n->in(0)->in(0));
+ C->gvn_replace_by(n->in(0), C->top());
+ }
+ }
+}
+
+
+StringConcat* StringConcat::merge(StringConcat* other, Node* arg) {
+ StringConcat* result = new StringConcat(_stringopts, _end);
+ for (uint x = 0; x < _control.size(); x++) {
+ Node* n = _control.at(x);
+ if (n->is_Call()) {
+ result->_control.push(n);
+ }
+ }
+ for (uint x = 0; x < other->_control.size(); x++) {
+ Node* n = other->_control.at(x);
+ if (n->is_Call()) {
+ result->_control.push(n);
+ }
+ }
+ assert(result->_control.contains(other->_end), "what?");
+ assert(result->_control.contains(_begin), "what?");
+ for (int x = 0; x < num_arguments(); x++) {
+ if (argument(x) == arg) {
+ // replace the toString result with the all the arguments that
+ // made up the other StringConcat
+ for (int y = 0; y < other->num_arguments(); y++) {
+ result->append(other->argument(y), other->mode(y));
+ }
+ } else {
+ result->append(argument(x), mode(x));
+ }
+ }
+ result->set_allocation(other->_begin);
+ result->_multiple = true;
+ return result;
+}
+
+
+void StringConcat::eliminate_call(CallNode* call) {
+ Compile* C = _stringopts->C;
+ CallProjections projs;
+ call->extract_projections(&projs, false);
+ if (projs.fallthrough_catchproj != NULL) {
+ C->gvn_replace_by(projs.fallthrough_catchproj, call->in(TypeFunc::Control));
+ }
+ if (projs.fallthrough_memproj != NULL) {
+ C->gvn_replace_by(projs.fallthrough_memproj, call->in(TypeFunc::Memory));
+ }
+ if (projs.catchall_memproj != NULL) {
+ C->gvn_replace_by(projs.catchall_memproj, C->top());
+ }
+ if (projs.fallthrough_ioproj != NULL) {
+ C->gvn_replace_by(projs.fallthrough_ioproj, call->in(TypeFunc::I_O));
+ }
+ if (projs.catchall_ioproj != NULL) {
+ C->gvn_replace_by(projs.catchall_ioproj, C->top());
+ }
+ if (projs.catchall_catchproj != NULL) {
+ // EA can't cope with the partially collapsed graph this
+ // creates so put it on the worklist to be collapsed later.
+ for (SimpleDUIterator i(projs.catchall_catchproj); i.has_next(); i.next()) {
+ Node *use = i.get();
+ int opc = use->Opcode();
+ if (opc == Op_CreateEx || opc == Op_Region) {
+ _stringopts->record_dead_node(use);
+ }
+ }
+ C->gvn_replace_by(projs.catchall_catchproj, C->top());
+ }
+ if (projs.resproj != NULL) {
+ C->gvn_replace_by(projs.resproj, C->top());
+ }
+ C->gvn_replace_by(call, C->top());
+}
+
+void StringConcat::eliminate_initialize(InitializeNode* init) {
+ Compile* C = _stringopts->C;
+
+ // Eliminate Initialize node.
+ assert(init->outcnt() <= 2, "only a control and memory projection expected");
+ assert(init->req() <= InitializeNode::RawStores, "no pending inits");
+ Node *ctrl_proj = init->proj_out(TypeFunc::Control);
+ if (ctrl_proj != NULL) {
+ C->gvn_replace_by(ctrl_proj, init->in(TypeFunc::Control));
+ }
+ Node *mem_proj = init->proj_out(TypeFunc::Memory);
+ if (mem_proj != NULL) {
+ Node *mem = init->in(TypeFunc::Memory);
+ C->gvn_replace_by(mem_proj, mem);
+ }
+ C->gvn_replace_by(init, C->top());
+ init->disconnect_inputs(NULL);
+}
+
+Node_List PhaseStringOpts::collect_toString_calls() {
+ Node_List string_calls;
+ Node_List worklist;
+
+ _visited.Clear();
+
+ // Prime the worklist
+ for (uint i = 1; i < C->root()->len(); i++) {
+ Node* n = C->root()->in(i);
+ if (n != NULL && !_visited.test_set(n->_idx)) {
+ worklist.push(n);
+ }
+ }
+
+ while (worklist.size() > 0) {
+ Node* ctrl = worklist.pop();
+ if (ctrl->is_CallStaticJava()) {
+ CallStaticJavaNode* csj = ctrl->as_CallStaticJava();
+ ciMethod* m = csj->method();
+ if (m != NULL &&
+ (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||
+ m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString)) {
+ string_calls.push(csj);
+ }
+ }
+ if (ctrl->in(0) != NULL && !_visited.test_set(ctrl->in(0)->_idx)) {
+ worklist.push(ctrl->in(0));
+ }
+ if (ctrl->is_Region()) {
+ for (uint i = 1; i < ctrl->len(); i++) {
+ if (ctrl->in(i) != NULL && !_visited.test_set(ctrl->in(i)->_idx)) {
+ worklist.push(ctrl->in(i));
+ }
+ }
+ }
+ }
+ return string_calls;
+}
+
+
+StringConcat* PhaseStringOpts::build_candidate(CallStaticJavaNode* call) {
+ ciMethod* m = call->method();
+ ciSymbol* string_sig;
+ ciSymbol* int_sig;
+ ciSymbol* char_sig;
+ if (m->holder() == C->env()->StringBuilder_klass()) {
+ string_sig = ciSymbol::String_StringBuilder_signature();
+ int_sig = ciSymbol::int_StringBuilder_signature();
+ char_sig = ciSymbol::char_StringBuilder_signature();
+ } else if (m->holder() == C->env()->StringBuffer_klass()) {
+ string_sig = ciSymbol::String_StringBuffer_signature();
+ int_sig = ciSymbol::int_StringBuffer_signature();
+ char_sig = ciSymbol::char_StringBuffer_signature();
+ } else {
+ return NULL;
+ }
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print("considering toString call in ");
+ call->jvms()->dump_spec(tty); tty->cr();
+ }
+#endif
+
+ StringConcat* sc = new StringConcat(this, call);
+
+ AllocateNode* alloc = NULL;
+ InitializeNode* init = NULL;
+
+ // possible opportunity for StringBuilder fusion
+ CallStaticJavaNode* cnode = call;
+ while (cnode) {
+ Node* recv = cnode->in(TypeFunc::Parms)->uncast();
+ if (recv->is_Proj()) {
+ recv = recv->in(0);
+ }
+ cnode = recv->isa_CallStaticJava();
+ if (cnode == NULL) {
+ alloc = recv->isa_Allocate();
+ if (alloc == NULL) {
+ break;
+ }
+ // Find the constructor call
+ Node* result = alloc->result_cast();
+ if (result == NULL || !result->is_CheckCastPP()) {
+ // strange looking allocation
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print("giving up because allocation looks strange ");
+ alloc->jvms()->dump_spec(tty); tty->cr();
+ }
+#endif
+ break;
+ }
+ Node* constructor = NULL;
+ for (SimpleDUIterator i(result); i.has_next(); i.next()) {
+ CallStaticJavaNode *use = i.get()->isa_CallStaticJava();
+ if (use != NULL && use->method() != NULL &&
+ use->method()->name() == ciSymbol::object_initializer_name() &&
+ use->method()->holder() == m->holder()) {
+ // Matched the constructor.
+ ciSymbol* sig = use->method()->signature()->as_symbol();
+ if (sig == ciSymbol::void_method_signature() ||
+ sig == ciSymbol::int_void_signature() ||
+ sig == ciSymbol::string_void_signature()) {
+ if (sig == ciSymbol::string_void_signature()) {
+ // StringBuilder(String) so pick this up as the first argument
+ assert(use->in(TypeFunc::Parms + 1) != NULL, "what?");
+ sc->push_string(use->in(TypeFunc::Parms + 1));
+ }
+ // The int variant takes an initial size for the backing
+ // array so just treat it like the void version.
+ constructor = use;
+ } else {
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print("unexpected constructor signature: %s", sig->as_utf8());
+ }
+#endif
+ }
+ break;
+ }
+ }
+ if (constructor == NULL) {
+ // couldn't find constructor
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print("giving up because couldn't find constructor ");
+ alloc->jvms()->dump_spec(tty);
+ }
+#endif
+ break;
+ }
+
+ // Walked all the way back and found the constructor call so see
+ // if this call converted into a direct string concatenation.
+ sc->add_control(call);
+ sc->add_control(constructor);
+ sc->add_control(alloc);
+ sc->set_allocation(alloc);
+ if (sc->validate_control_flow()) {
+ return sc;
+ } else {
+ return NULL;
+ }
+ } else if (cnode->method() == NULL) {
+ break;
+ } else if (cnode->method()->holder() == m->holder() &&
+ cnode->method()->name() == ciSymbol::append_name() &&
+ (cnode->method()->signature()->as_symbol() == string_sig ||
+ cnode->method()->signature()->as_symbol() == char_sig ||
+ cnode->method()->signature()->as_symbol() == int_sig)) {
+ sc->add_control(cnode);
+ Node* arg = cnode->in(TypeFunc::Parms + 1);
+ if (cnode->method()->signature()->as_symbol() == int_sig) {
+ sc->push_int(arg);
+ } else if (cnode->method()->signature()->as_symbol() == char_sig) {
+ sc->push_char(arg);
+ } else {
+ if (arg->is_Proj() && arg->in(0)->is_CallStaticJava()) {
+ CallStaticJavaNode* csj = arg->in(0)->as_CallStaticJava();
+ if (csj->method() != NULL &&
+ csj->method()->holder() == C->env()->Integer_klass() &&
+ csj->method()->name() == ciSymbol::toString_name()) {
+ sc->add_control(csj);
+ sc->push_int(csj->in(TypeFunc::Parms));
+ continue;
+ }
+ }
+ sc->push_string(arg);
+ }
+ continue;
+ } else {
+ // some unhandled signature
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print("giving up because encountered unexpected signature ");
+ cnode->tf()->dump(); tty->cr();
+ cnode->in(TypeFunc::Parms + 1)->dump();
+ }
+#endif
+ break;
+ }
+ }
+ return NULL;
+}
+
+
+PhaseStringOpts::PhaseStringOpts(PhaseGVN* gvn, Unique_Node_List*):
+ Phase(StringOpts),
+ _gvn(gvn),
+ _visited(Thread::current()->resource_area()) {
+
+ assert(OptimizeStringConcat, "shouldn't be here");
+
+ size_table_field = C->env()->Integer_klass()->get_field_by_name(ciSymbol::make("sizeTable"),
+ ciSymbol::make("[I"), true);
+ if (size_table_field == NULL) {
+ // Something wrong so give up.
+ assert(false, "why can't we find Integer.sizeTable?");
+ return;
+ }
+
+ // Collect the types needed to talk about the various slices of memory
+ const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
+ false, NULL, 0);
+
+ const TypePtr* value_field_type = string_type->add_offset(java_lang_String::value_offset_in_bytes());
+ const TypePtr* offset_field_type = string_type->add_offset(java_lang_String::offset_offset_in_bytes());
+ const TypePtr* count_field_type = string_type->add_offset(java_lang_String::count_offset_in_bytes());
+
+ value_field_idx = C->get_alias_index(value_field_type);
+ count_field_idx = C->get_alias_index(count_field_type);
+ offset_field_idx = C->get_alias_index(offset_field_type);
+ char_adr_idx = C->get_alias_index(TypeAryPtr::CHARS);
+
+ // For each locally allocated StringBuffer see if the usages can be
+ // collapsed into a single String construction.
+
+ // Run through the list of allocation looking for SB.toString to see
+ // if it's possible to fuse the usage of the SB into a single String
+ // construction.
+ GrowableArray<StringConcat*> concats;
+ Node_List toStrings = collect_toString_calls();
+ while (toStrings.size() > 0) {
+ StringConcat* sc = build_candidate(toStrings.pop()->as_CallStaticJava());
+ if (sc != NULL) {
+ concats.push(sc);
+ }
+ }
+
+ // try to coalesce separate concats
+ restart:
+ for (int c = 0; c < concats.length(); c++) {
+ StringConcat* sc = concats.at(c);
+ for (int i = 0; i < sc->num_arguments(); i++) {
+ Node* arg = sc->argument(i);
+ if (arg->is_Proj() && arg->in(0)->is_CallStaticJava()) {
+ CallStaticJavaNode* csj = arg->in(0)->as_CallStaticJava();
+ if (csj->method() != NULL &&
+ (csj->method()->holder() == C->env()->StringBuffer_klass() ||
+ csj->method()->holder() == C->env()->StringBuilder_klass()) &&
+ csj->method()->name() == ciSymbol::toString_name()) {
+ for (int o = 0; o < concats.length(); o++) {
+ if (c == o) continue;
+ StringConcat* other = concats.at(o);
+ if (other->end() == csj) {
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print_cr("considering stacked concats");
+ }
+#endif
+
+ StringConcat* merged = sc->merge(other, arg);
+ if (merged->validate_control_flow()) {
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print_cr("stacking would succeed");
+ }
+#endif
+ if (c < o) {
+ concats.remove_at(o);
+ concats.at_put(c, merged);
+ } else {
+ concats.remove_at(c);
+ concats.at_put(o, merged);
+ }
+ goto restart;
+ } else {
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print_cr("stacking would fail");
+ }
+#endif
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+
+
+ for (int c = 0; c < concats.length(); c++) {
+ StringConcat* sc = concats.at(c);
+ replace_string_concat(sc);
+ }
+
+ remove_dead_nodes();
+}
+
+void PhaseStringOpts::record_dead_node(Node* dead) {
+ dead_worklist.push(dead);
+}
+
+void PhaseStringOpts::remove_dead_nodes() {
+ // Delete any dead nodes to make things clean enough that escape
+ // analysis doesn't get unhappy.
+ while (dead_worklist.size() > 0) {
+ Node* use = dead_worklist.pop();
+ int opc = use->Opcode();
+ switch (opc) {
+ case Op_Region: {
+ uint i = 1;
+ for (i = 1; i < use->req(); i++) {
+ if (use->in(i) != C->top()) {
+ break;
+ }
+ }
+ if (i >= use->req()) {
+ for (SimpleDUIterator i(use); i.has_next(); i.next()) {
+ Node* m = i.get();
+ if (m->is_Phi()) {
+ dead_worklist.push(m);
+ }
+ }
+ C->gvn_replace_by(use, C->top());
+ }
+ break;
+ }
+ case Op_AddP:
+ case Op_CreateEx: {
+ // Recurisvely clean up references to CreateEx so EA doesn't
+ // get unhappy about the partially collapsed graph.
+ for (SimpleDUIterator i(use); i.has_next(); i.next()) {
+ Node* m = i.get();
+ if (m->is_AddP()) {
+ dead_worklist.push(m);
+ }
+ }
+ C->gvn_replace_by(use, C->top());
+ break;
+ }
+ case Op_Phi:
+ if (use->in(0) == C->top()) {
+ C->gvn_replace_by(use, C->top());
+ }
+ break;
+ }
+ }
+}
+
+
+bool StringConcat::validate_control_flow() {
+ // We found all the calls and arguments now lets see if it's
+ // safe to transform the graph as we would expect.
+
+ // Check to see if this resulted in too many uncommon traps previously
+ if (Compile::current()->too_many_traps(_begin->jvms()->method(), _begin->jvms()->bci(),
+ Deoptimization::Reason_intrinsic)) {
+ return false;
+ }
+
+ // Walk backwards over the control flow from toString to the
+ // allocation and make sure all the control flow is ok. This
+ // means it's either going to be eliminated once the calls are
+ // removed or it can safely be transformed into an uncommon
+ // trap.
+
+ int null_check_count = 0;
+ Unique_Node_List ctrl_path;
+
+ assert(_control.contains(_begin), "missing");
+ assert(_control.contains(_end), "missing");
+
+ // Collect the nodes that we know about and will eliminate into ctrl_path
+ for (uint i = 0; i < _control.size(); i++) {
+ // Push the call and it's control projection
+ Node* n = _control.at(i);
+ if (n->is_Allocate()) {
+ AllocateNode* an = n->as_Allocate();
+ InitializeNode* init = an->initialization();
+ ctrl_path.push(init);
+ ctrl_path.push(init->as_Multi()->proj_out(0));
+ }
+ if (n->is_Call()) {
+ CallNode* cn = n->as_Call();
+ ctrl_path.push(cn);
+ ctrl_path.push(cn->proj_out(0));
+ ctrl_path.push(cn->proj_out(0)->unique_out());
+ ctrl_path.push(cn->proj_out(0)->unique_out()->as_Catch()->proj_out(0));
+ } else {
+ ShouldNotReachHere();
+ }
+ }
+
+ // Skip backwards through the control checking for unexpected contro flow
+ Node* ptr = _end;
+ bool fail = false;
+ while (ptr != _begin) {
+ if (ptr->is_Call() && ctrl_path.member(ptr)) {
+ ptr = ptr->in(0);
+ } else if (ptr->is_CatchProj() && ctrl_path.member(ptr)) {
+ ptr = ptr->in(0)->in(0)->in(0);
+ assert(ctrl_path.member(ptr), "should be a known piece of control");
+ } else if (ptr->is_IfTrue()) {
+ IfNode* iff = ptr->in(0)->as_If();
+ BoolNode* b = iff->in(1)->isa_Bool();
+ Node* cmp = b->in(1);
+ Node* v1 = cmp->in(1);
+ Node* v2 = cmp->in(2);
+ Node* otherproj = iff->proj_out(1 - ptr->as_Proj()->_con);
+
+ // Null check of the return of append which can simply be eliminated
+ if (b->_test._test == BoolTest::ne &&
+ v2->bottom_type() == TypePtr::NULL_PTR &&
+ v1->is_Proj() && ctrl_path.member(v1->in(0))) {
+ // NULL check of the return value of the append
+ null_check_count++;
+ if (otherproj->outcnt() == 1) {
+ CallStaticJavaNode* call = otherproj->unique_out()->isa_CallStaticJava();
+ if (call != NULL && call->_name != NULL && strcmp(call->_name, "uncommon_trap") == 0) {
+ ctrl_path.push(call);
+ }
+ }
+ _control.push(ptr);
+ ptr = ptr->in(0)->in(0);
+ continue;
+ }
+
+ // A test which leads to an uncommon trap which should be safe.
+ // Later this trap will be converted into a trap that restarts
+ // at the beginning.
+ if (otherproj->outcnt() == 1) {
+ CallStaticJavaNode* call = otherproj->unique_out()->isa_CallStaticJava();
+ if (call != NULL && call->_name != NULL && strcmp(call->_name, "uncommon_trap") == 0) {
+ // control flow leads to uct so should be ok
+ _uncommon_traps.push(call);
+ ctrl_path.push(call);
+ ptr = ptr->in(0)->in(0);
+ continue;
+ }
+ }
+
+#ifndef PRODUCT
+ // Some unexpected control flow we don't know how to handle.
+ if (PrintOptimizeStringConcat) {
+ tty->print_cr("failing with unknown test");
+ b->dump();
+ cmp->dump();
+ v1->dump();
+ v2->dump();
+ tty->cr();
+ }
+#endif
+ break;
+ } else if (ptr->is_Proj() && ptr->in(0)->is_Initialize()) {
+ ptr = ptr->in(0)->in(0);
+ } else if (ptr->is_Region()) {
+ Node* copy = ptr->as_Region()->is_copy();
+ if (copy != NULL) {
+ ptr = copy;
+ continue;
+ }
+ if (ptr->req() == 3 &&
+ ptr->in(1) != NULL && ptr->in(1)->is_Proj() &&
+ ptr->in(2) != NULL && ptr->in(2)->is_Proj() &&
+ ptr->in(1)->in(0) == ptr->in(2)->in(0) &&
+ ptr->in(1)->in(0) != NULL && ptr->in(1)->in(0)->is_If()) {
+ // Simple diamond.
+ // XXX should check for possibly merging stores. simple data merges are ok.
+ ptr = ptr->in(1)->in(0)->in(0);
+ continue;
+ }
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print_cr("fusion would fail for region");
+ _begin->dump();
+ ptr->dump(2);
+ }
+#endif
+ fail = true;
+ break;
+ } else {
+ // other unknown control
+ if (!fail) {
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ tty->print_cr("fusion would fail for");
+ _begin->dump();
+ }
+#endif
+ fail = true;
+ }
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ ptr->dump();
+ }
+#endif
+ ptr = ptr->in(0);
+ }
+ }
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat && fail) {
+ tty->cr();
+ }
+#endif
+ if (fail) return !fail;
+
+ // Validate that all these results produced are contained within
+ // this cluster of objects. First collect all the results produced
+ // by calls in the region.
+ _stringopts->_visited.Clear();
+ Node_List worklist;
+ Node* final_result = _end->proj_out(TypeFunc::Parms);
+ for (uint i = 0; i < _control.size(); i++) {
+ CallNode* cnode = _control.at(i)->isa_Call();
+ if (cnode != NULL) {
+ _stringopts->_visited.test_set(cnode->_idx);
+ }
+ Node* result = cnode != NULL ? cnode->proj_out(TypeFunc::Parms) : NULL;
+ if (result != NULL && result != final_result) {
+ worklist.push(result);
+ }
+ }
+
+ Node* last_result = NULL;
+ while (worklist.size() > 0) {
+ Node* result = worklist.pop();
+ if (_stringopts->_visited.test_set(result->_idx))
+ continue;
+ for (SimpleDUIterator i(result); i.has_next(); i.next()) {
+ Node *use = i.get();
+ if (ctrl_path.member(use)) {
+ // already checked this
+ continue;
+ }
+ int opc = use->Opcode();
+ if (opc == Op_CmpP || opc == Op_Node) {
+ ctrl_path.push(use);
+ continue;
+ }
+ if (opc == Op_CastPP || opc == Op_CheckCastPP) {
+ for (SimpleDUIterator j(use); j.has_next(); j.next()) {
+ worklist.push(j.get());
+ }
+ worklist.push(use->in(1));
+ ctrl_path.push(use);
+ continue;
+ }
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat) {
+ if (result != last_result) {
+ last_result = result;
+ tty->print_cr("extra uses for result:");
+ last_result->dump();
+ }
+ use->dump();
+ }
+#endif
+ fail = true;
+ break;
+ }
+ }
+
+#ifndef PRODUCT
+ if (PrintOptimizeStringConcat && !fail) {
+ ttyLocker ttyl;
+ tty->cr();
+ tty->print("fusion would succeed (%d %d) for ", null_check_count, _uncommon_traps.size());
+ _begin->jvms()->dump_spec(tty); tty->cr();
+ for (int i = 0; i < num_arguments(); i++) {
+ argument(i)->dump();
+ }
+ _control.dump();
+ tty->cr();
+ }
+#endif
+
+ return !fail;
+}
+
+Node* PhaseStringOpts::fetch_static_field(GraphKit& kit, ciField* field) {
+ const TypeKlassPtr* klass_type = TypeKlassPtr::make(field->holder());
+ Node* klass_node = __ makecon(klass_type);
+ BasicType bt = field->layout_type();
+ ciType* field_klass = field->type();
+
+ const Type *type;
+ if( bt == T_OBJECT ) {
+ if (!field->type()->is_loaded()) {
+ type = TypeInstPtr::BOTTOM;
+ } else if (field->is_constant()) {
+ // This can happen if the constant oop is non-perm.
+ ciObject* con = field->constant_value().as_object();
+ // Do not "join" in the previous type; it doesn't add value,
+ // and may yield a vacuous result if the field is of interface type.
+ type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
+ assert(type != NULL, "field singleton type must be consistent");
+ } else {
+ type = TypeOopPtr::make_from_klass(field_klass->as_klass());
+ }
+ } else {
+ type = Type::get_const_basic_type(bt);
+ }
+
+ return kit.make_load(NULL, kit.basic_plus_adr(klass_node, field->offset_in_bytes()),
+ type, T_OBJECT,
+ C->get_alias_index(klass_type->add_offset(field->offset_in_bytes())));
+}
+
+Node* PhaseStringOpts::int_stringSize(GraphKit& kit, Node* arg) {
+ RegionNode *final_merge = new (C, 3) RegionNode(3);
+ kit.gvn().set_type(final_merge, Type::CONTROL);
+ Node* final_size = new (C, 3) PhiNode(final_merge, TypeInt::INT);
+ kit.gvn().set_type(final_size, TypeInt::INT);
+
+ IfNode* iff = kit.create_and_map_if(kit.control(),
+ __ Bool(__ CmpI(arg, __ intcon(0x80000000)), BoolTest::ne),
+ PROB_FAIR, COUNT_UNKNOWN);
+ Node* is_min = __ IfFalse(iff);
+ final_merge->init_req(1, is_min);
+ final_size->init_req(1, __ intcon(11));
+
+ kit.set_control(__ IfTrue(iff));
+ if (kit.stopped()) {
+ final_merge->init_req(2, C->top());
+ final_size->init_req(2, C->top());
+ } else {
+
+ // int size = (i < 0) ? stringSize(-i) + 1 : stringSize(i);
+ RegionNode *r = new (C, 3) RegionNode(3);
+ kit.gvn().set_type(r, Type::CONTROL);
+ Node *phi = new (C, 3) PhiNode(r, TypeInt::INT);
+ kit.gvn().set_type(phi, TypeInt::INT);
+ Node *size = new (C, 3) PhiNode(r, TypeInt::INT);
+ kit.gvn().set_type(size, TypeInt::INT);
+ Node* chk = __ CmpI(arg, __ intcon(0));
+ Node* p = __ Bool(chk, BoolTest::lt);
+ IfNode* iff = kit.create_and_map_if(kit.control(), p, PROB_FAIR, COUNT_UNKNOWN);
+ Node* lessthan = __ IfTrue(iff);
+ Node* greaterequal = __ IfFalse(iff);
+ r->init_req(1, lessthan);
+ phi->init_req(1, __ SubI(__ intcon(0), arg));
+ size->init_req(1, __ intcon(1));
+ r->init_req(2, greaterequal);
+ phi->init_req(2, arg);
+ size->init_req(2, __ intcon(0));
+ kit.set_control(r);
+ C->record_for_igvn(r);
+ C->record_for_igvn(phi);
+ C->record_for_igvn(size);
+
+ // for (int i=0; ; i++)
+ // if (x <= sizeTable[i])
+ // return i+1;
+ RegionNode *loop = new (C, 3) RegionNode(3);
+ loop->init_req(1, kit.control());
+ kit.gvn().set_type(loop, Type::CONTROL);
+
+ Node *index = new (C, 3) PhiNode(loop, TypeInt::INT);
+ index->init_req(1, __ intcon(0));
+ kit.gvn().set_type(index, TypeInt::INT);
+ kit.set_control(loop);
+ Node* sizeTable = fetch_static_field(kit, size_table_field);
+
+ Node* value = kit.load_array_element(NULL, sizeTable, index, TypeAryPtr::INTS);
+ C->record_for_igvn(value);
+ Node* limit = __ CmpI(phi, value);
+ Node* limitb = __ Bool(limit, BoolTest::le);
+ IfNode* iff2 = kit.create_and_map_if(kit.control(), limitb, PROB_MIN, COUNT_UNKNOWN);
+ Node* lessEqual = __ IfTrue(iff2);
+ Node* greater = __ IfFalse(iff2);
+
+ loop->init_req(2, greater);
+ index->init_req(2, __ AddI(index, __ intcon(1)));
+
+ kit.set_control(lessEqual);
+ C->record_for_igvn(loop);
+ C->record_for_igvn(index);
+
+ final_merge->init_req(2, kit.control());
+ final_size->init_req(2, __ AddI(__ AddI(index, size), __ intcon(1)));
+ }
+
+ kit.set_control(final_merge);
+ C->record_for_igvn(final_merge);
+ C->record_for_igvn(final_size);
+
+ return final_size;
+}
+
+void PhaseStringOpts::int_getChars(GraphKit& kit, Node* arg, Node* char_array, Node* start, Node* end) {
+ RegionNode *final_merge = new (C, 4) RegionNode(4);
+ kit.gvn().set_type(final_merge, Type::CONTROL);
+ Node *final_mem = PhiNode::make(final_merge, kit.memory(char_adr_idx), Type::MEMORY, TypeAryPtr::CHARS);
+ kit.gvn().set_type(final_mem, Type::MEMORY);
+
+ // need to handle Integer.MIN_VALUE specially because negating doesn't make it positive
+ {
+ // i == MIN_VALUE
+ IfNode* iff = kit.create_and_map_if(kit.control(),
+ __ Bool(__ CmpI(arg, __ intcon(0x80000000)), BoolTest::ne),
+ PROB_FAIR, COUNT_UNKNOWN);
+
+ Node* old_mem = kit.memory(char_adr_idx);
+
+ kit.set_control(__ IfFalse(iff));
+ if (kit.stopped()) {
+ // Statically not equal to MIN_VALUE so this path is dead
+ final_merge->init_req(3, kit.control());
+ } else {
+ copy_string(kit, __ makecon(TypeInstPtr::make(C->env()->the_min_jint_string())),
+ char_array, start);
+ final_merge->init_req(3, kit.control());
+ final_mem->init_req(3, kit.memory(char_adr_idx));
+ }
+
+ kit.set_control(__ IfTrue(iff));
+ kit.set_memory(old_mem, char_adr_idx);
+ }
+
+
+ // Simplified version of Integer.getChars
+
+ // int q, r;
+ // int charPos = index;
+ Node* charPos = end;
+
+ // char sign = 0;
+
+ Node* i = arg;
+ Node* sign = __ intcon(0);
+
+ // if (i < 0) {
+ // sign = '-';
+ // i = -i;
+ // }
+ {
+ IfNode* iff = kit.create_and_map_if(kit.control(),
+ __ Bool(__ CmpI(arg, __ intcon(0)), BoolTest::lt),
+ PROB_FAIR, COUNT_UNKNOWN);
+
+ RegionNode *merge = new (C, 3) RegionNode(3);
+ kit.gvn().set_type(merge, Type::CONTROL);
+ i = new (C, 3) PhiNode(merge, TypeInt::INT);
+ kit.gvn().set_type(i, TypeInt::INT);
+ sign = new (C, 3) PhiNode(merge, TypeInt::INT);
+ kit.gvn().set_type(sign, TypeInt::INT);
+
+ merge->init_req(1, __ IfTrue(iff));
+ i->init_req(1, __ SubI(__ intcon(0), arg));
+ sign->init_req(1, __ intcon('-'));
+ merge->init_req(2, __ IfFalse(iff));
+ i->init_req(2, arg);
+ sign->init_req(2, __ intcon(0));
+
+ kit.set_control(merge);
+
+ C->record_for_igvn(merge);
+ C->record_for_igvn(i);
+ C->record_for_igvn(sign);
+ }
+
+ // for (;;) {
+ // q = i / 10;
+ // r = i - ((q << 3) + (q << 1)); // r = i-(q*10) ...
+ // buf [--charPos] = digits [r];
+ // i = q;
+ // if (i == 0) break;
+ // }
+
+ {
+ RegionNode *head = new (C, 3) RegionNode(3);
+ head->init_req(1, kit.control());
+ kit.gvn().set_type(head, Type::CONTROL);
+ Node *i_phi = new (C, 3) PhiNode(head, TypeInt::INT);
+ i_phi->init_req(1, i);
+ kit.gvn().set_type(i_phi, TypeInt::INT);
+ charPos = PhiNode::make(head, charPos);
+ kit.gvn().set_type(charPos, TypeInt::INT);
+ Node *mem = PhiNode::make(head, kit.memory(char_adr_idx), Type::MEMORY, TypeAryPtr::CHARS);
+ kit.gvn().set_type(mem, Type::MEMORY);
+ kit.set_control(head);
+ kit.set_memory(mem, char_adr_idx);
+
+ Node* q = __ DivI(kit.null(), i_phi, __ intcon(10));
+ Node* r = __ SubI(i_phi, __ AddI(__ LShiftI(q, __ intcon(3)),
+ __ LShiftI(q, __ intcon(1))));
+ Node* m1 = __ SubI(charPos, __ intcon(1));
+ Node* ch = __ AddI(r, __ intcon('0'));
+
+ Node* st = __ store_to_memory(kit.control(), kit.array_element_address(char_array, m1, T_CHAR),
+ ch, T_CHAR, char_adr_idx);
+
+
+ IfNode* iff = kit.create_and_map_if(head, __ Bool(__ CmpI(q, __ intcon(0)), BoolTest::ne),
+ PROB_FAIR, COUNT_UNKNOWN);
+ Node* ne = __ IfTrue(iff);
+ Node* eq = __ IfFalse(iff);
+
+ head->init_req(2, ne);
+ mem->init_req(2, st);
+ i_phi->init_req(2, q);
+ charPos->init_req(2, m1);
+
+ charPos = m1;
+
+ kit.set_control(eq);
+ kit.set_memory(st, char_adr_idx);
+
+ C->record_for_igvn(head);
+ C->record_for_igvn(mem);
+ C->record_for_igvn(i_phi);
+ C->record_for_igvn(charPos);
+ }
+
+ {
+ // if (sign != 0) {
+ // buf [--charPos] = sign;
+ // }
+ IfNode* iff = kit.create_and_map_if(kit.control(),
+ __ Bool(__ CmpI(sign, __ intcon(0)), BoolTest::ne),
+ PROB_FAIR, COUNT_UNKNOWN);
+
+ final_merge->init_req(2, __ IfFalse(iff));
+ final_mem->init_req(2, kit.memory(char_adr_idx));
+
+ kit.set_control(__ IfTrue(iff));
+ if (kit.stopped()) {
+ final_merge->init_req(1, C->top());
+ final_mem->init_req(1, C->top());
+ } else {
+ Node* m1 = __ SubI(charPos, __ intcon(1));
+ Node* st = __ store_to_memory(kit.control(), kit.array_element_address(char_array, m1, T_CHAR),
+ sign, T_CHAR, char_adr_idx);
+
+ final_merge->init_req(1, kit.control());
+ final_mem->init_req(1, st);
+ }
+
+ kit.set_control(final_merge);
+ kit.set_memory(final_mem, char_adr_idx);
+
+ C->record_for_igvn(final_merge);
+ C->record_for_igvn(final_mem);
+ }
+}
+
+
+Node* PhaseStringOpts::copy_string(GraphKit& kit, Node* str, Node* char_array, Node* start) {
+ Node* string = str;
+ Node* offset = kit.make_load(NULL,
+ kit.basic_plus_adr(string, string, java_lang_String::offset_offset_in_bytes()),
+ TypeInt::INT, T_INT, offset_field_idx);
+ Node* count = kit.make_load(NULL,
+ kit.basic_plus_adr(string, string, java_lang_String::count_offset_in_bytes()),
+ TypeInt::INT, T_INT, count_field_idx);
+ const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
+ TypeAry::make(TypeInt::CHAR,TypeInt::POS),
+ ciTypeArrayKlass::make(T_CHAR), true, 0);
+ Node* value = kit.make_load(NULL,
+ kit.basic_plus_adr(string, string, java_lang_String::value_offset_in_bytes()),
+ value_type, T_OBJECT, value_field_idx);
+
+ // copy the contents
+ if (offset->is_Con() && count->is_Con() && value->is_Con() && count->get_int() < unroll_string_copy_length) {
+ // For small constant strings just emit individual stores.
+ // A length of 6 seems like a good space/speed tradeof.
+ int c = count->get_int();
+ int o = offset->get_int();
+ const TypeOopPtr* t = kit.gvn().type(value)->isa_oopptr();
+ ciTypeArray* value_array = t->const_oop()->as_type_array();
+ for (int e = 0; e < c; e++) {
+ __ store_to_memory(kit.control(), kit.array_element_address(char_array, start, T_CHAR),
+ __ intcon(value_array->char_at(o + e)), T_CHAR, char_adr_idx);
+ start = __ AddI(start, __ intcon(1));
+ }
+ } else {
+ Node* src_ptr = kit.array_element_address(value, offset, T_CHAR);
+ Node* dst_ptr = kit.array_element_address(char_array, start, T_CHAR);
+ Node* c = count;
+ Node* extra = NULL;
+#ifdef _LP64
+ c = __ ConvI2L(c);
+ extra = C->top();
+#endif
+ Node* call = kit.make_runtime_call(GraphKit::RC_LEAF|GraphKit::RC_NO_FP,
+ OptoRuntime::fast_arraycopy_Type(),
+ CAST_FROM_FN_PTR(address, StubRoutines::jshort_disjoint_arraycopy()),
+ "jshort_disjoint_arraycopy", TypeAryPtr::CHARS,
+ src_ptr, dst_ptr, c, extra);
+ start = __ AddI(start, count);
+ }
+ return start;
+}
+
+
+void PhaseStringOpts::replace_string_concat(StringConcat* sc) {
+ // Log a little info about the transformation
+ sc->maybe_log_transform();
+
+ // pull the JVMState of the allocation into a SafePointNode to serve as
+ // as a shim for the insertion of the new code.
+ JVMState* jvms = sc->begin()->jvms()->clone_shallow(C);
+ uint size = sc->begin()->req();
+ SafePointNode* map = new (C, size) SafePointNode(size, jvms);
+
+ // copy the control and memory state from the final call into our
+ // new starting state. This allows any preceeding tests to feed
+ // into the new section of code.
+ for (uint i1 = 0; i1 < TypeFunc::Parms; i1++) {
+ map->init_req(i1, sc->end()->in(i1));
+ }
+ // blow away old allocation arguments
+ for (uint i1 = TypeFunc::Parms; i1 < jvms->debug_start(); i1++) {
+ map->init_req(i1, C->top());
+ }
+ // Copy the rest of the inputs for the JVMState
+ for (uint i1 = jvms->debug_start(); i1 < sc->begin()->req(); i1++) {
+ map->init_req(i1, sc->begin()->in(i1));
+ }
+ // Make sure the memory state is a MergeMem for parsing.
+ if (!map->in(TypeFunc::Memory)->is_MergeMem()) {
+ map->set_req(TypeFunc::Memory, MergeMemNode::make(C, map->in(TypeFunc::Memory)));
+ }
+
+ jvms->set_map(map);
+ map->ensure_stack(jvms, jvms->method()->max_stack());
+
+
+ // disconnect all the old StringBuilder calls from the graph
+ sc->eliminate_unneeded_control();
+
+ // At this point all the old work has been completely removed from
+ // the graph and the saved JVMState exists at the point where the
+ // final toString call used to be.
+ GraphKit kit(jvms);
+
+ // There may be uncommon traps which are still using the
+ // intermediate states and these need to be rewritten to point at
+ // the JVMState at the beginning of the transformation.
+ sc->convert_uncommon_traps(kit, jvms);
+
+ // Now insert the logic to compute the size of the string followed
+ // by all the logic to construct array and resulting string.
+
+ Node* null_string = __ makecon(TypeInstPtr::make(C->env()->the_null_string()));
+
+ // Create a region for the overflow checks to merge into.
+ int args = MAX2(sc->num_arguments(), 1);
+ RegionNode* overflow = new (C, args) RegionNode(args);
+ kit.gvn().set_type(overflow, Type::CONTROL);
+
+ // Create a hook node to hold onto the individual sizes since they
+ // are need for the copying phase.
+ Node* string_sizes = new (C, args) Node(args);
+
+ Node* length = __ intcon(0);
+ for (int argi = 0; argi < sc->num_arguments(); argi++) {
+ Node* arg = sc->argument(argi);
+ switch (sc->mode(argi)) {
+ case StringConcat::IntMode: {
+ Node* string_size = int_stringSize(kit, arg);
+
+ // accumulate total
+ length = __ AddI(length, string_size);
+
+ // Cache this value for the use by int_toString
+ string_sizes->init_req(argi, string_size);
+ break;
+ }
+ case StringConcat::StringMode: {
+ const Type* type = kit.gvn().type(arg);
+ if (type == TypePtr::NULL_PTR) {
+ // replace the argument with the null checked version
+ arg = null_string;
+ sc->set_argument(argi, arg);
+ } else if (!type->higher_equal(TypeInstPtr::NOTNULL)) {
+ // s = s != null ? s : "null";
+ // length = length + (s.count - s.offset);
+ RegionNode *r = new (C, 3) RegionNode(3);
+ kit.gvn().set_type(r, Type::CONTROL);
+ Node *phi = new (C, 3) PhiNode(r, type->join(TypeInstPtr::NOTNULL));
+ kit.gvn().set_type(phi, phi->bottom_type());
+ Node* p = __ Bool(__ CmpP(arg, kit.null()), BoolTest::ne);
+ IfNode* iff = kit.create_and_map_if(kit.control(), p, PROB_MIN, COUNT_UNKNOWN);
+ Node* notnull = __ IfTrue(iff);
+ Node* isnull = __ IfFalse(iff);
+ r->init_req(1, notnull);
+ phi->init_req(1, arg);
+ r->init_req(2, isnull);
+ phi->init_req(2, null_string);
+ kit.set_control(r);
+ C->record_for_igvn(r);
+ C->record_for_igvn(phi);
+ // replace the argument with the null checked version
+ arg = phi;
+ sc->set_argument(argi, arg);
+ }
+ // Node* offset = kit.make_load(NULL, kit.basic_plus_adr(arg, arg, offset_offset),
+ // TypeInt::INT, T_INT, offset_field_idx);
+ Node* count = kit.make_load(NULL, kit.basic_plus_adr(arg, arg, java_lang_String::count_offset_in_bytes()),
+ TypeInt::INT, T_INT, count_field_idx);
+ length = __ AddI(length, count);
+ string_sizes->init_req(argi, NULL);
+ break;
+ }
+ case StringConcat::CharMode: {
+ // one character only
+ length = __ AddI(length, __ intcon(1));
+ break;
+ }
+ default:
+ ShouldNotReachHere();
+ }
+ if (argi > 0) {
+ // Check that the sum hasn't overflowed
+ IfNode* iff = kit.create_and_map_if(kit.control(),
+ __ Bool(__ CmpI(length, __ intcon(0)), BoolTest::lt),
+ PROB_MIN, COUNT_UNKNOWN);
+ kit.set_control(__ IfFalse(iff));
+ overflow->set_req(argi, __ IfTrue(iff));
+ }
+ }
+
+ {
+ // Hook
+ PreserveJVMState pjvms(&kit);
+ kit.set_control(overflow);
+ kit.uncommon_trap(Deoptimization::Reason_intrinsic,
+ Deoptimization::Action_make_not_entrant);
+ }
+
+ // length now contains the number of characters needed for the
+ // char[] so create a new AllocateArray for the char[]
+ Node* char_array = NULL;
+ {
+ PreserveReexecuteState preexecs(&kit);
+ // The original jvms is for an allocation of either a String or
+ // StringBuffer so no stack adjustment is necessary for proper
+ // reexecution. If we deoptimize in the slow path the bytecode
+ // will be reexecuted and the char[] allocation will be thrown away.
+ kit.jvms()->set_should_reexecute(true);
+ char_array = kit.new_array(__ makecon(TypeKlassPtr::make(ciTypeArrayKlass::make(T_CHAR))),
+ length, 1);
+ }
+
+ // Mark the allocation so that zeroing is skipped since the code
+ // below will overwrite the entire array
+ AllocateArrayNode* char_alloc = AllocateArrayNode::Ideal_array_allocation(char_array, _gvn);
+ char_alloc->maybe_set_complete(_gvn);
+
+ // Now copy the string representations into the final char[]
+ Node* start = __ intcon(0);
+ for (int argi = 0; argi < sc->num_arguments(); argi++) {
+ Node* arg = sc->argument(argi);
+ switch (sc->mode(argi)) {
+ case StringConcat::IntMode: {
+ Node* end = __ AddI(start, string_sizes->in(argi));
+ // getChars words backwards so pass the ending point as well as the start
+ int_getChars(kit, arg, char_array, start, end);
+ start = end;
+ break;
+ }
+ case StringConcat::StringMode: {
+ start = copy_string(kit, arg, char_array, start);
+ break;
+ }
+ case StringConcat::CharMode: {
+ __ store_to_memory(kit.control(), kit.array_element_address(char_array, start, T_CHAR),
+ arg, T_CHAR, char_adr_idx);
+ start = __ AddI(start, __ intcon(1));
+ break;
+ }
+ default:
+ ShouldNotReachHere();
+ }
+ }
+
+ // If we're not reusing an existing String allocation then allocate one here.
+ Node* result = sc->string_alloc();
+ if (result == NULL) {
+ PreserveReexecuteState preexecs(&kit);
+ // The original jvms is for an allocation of either a String or
+ // StringBuffer so no stack adjustment is necessary for proper
+ // reexecution.
+ kit.jvms()->set_should_reexecute(true);
+ result = kit.new_instance(__ makecon(TypeKlassPtr::make(C->env()->String_klass())));
+ }
+
+ // Intialize the string
+ kit.store_to_memory(kit.control(), kit.basic_plus_adr(result, java_lang_String::offset_offset_in_bytes()),
+ __ intcon(0), T_INT, offset_field_idx);
+ kit.store_to_memory(kit.control(), kit.basic_plus_adr(result, java_lang_String::count_offset_in_bytes()),
+ length, T_INT, count_field_idx);
+ kit.store_to_memory(kit.control(), kit.basic_plus_adr(result, java_lang_String::value_offset_in_bytes()),
+ char_array, T_OBJECT, value_field_idx);
+
+ // hook up the outgoing control and result
+ kit.replace_call(sc->end(), result);
+
+ // Unhook any hook nodes
+ string_sizes->disconnect_inputs(NULL);
+ sc->cleanup();
+}