| /* |
| * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "ci/ciArrayKlass.hpp" |
| #include "ci/ciEnv.hpp" |
| #include "ci/ciKlass.hpp" |
| #include "ci/ciMethod.hpp" |
| #include "code/dependencies.hpp" |
| #include "compiler/compileLog.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "runtime/handles.hpp" |
| #include "runtime/handles.inline.hpp" |
| #include "utilities/copy.hpp" |
| |
| |
| #ifdef ASSERT |
| static bool must_be_in_vm() { |
| Thread* thread = Thread::current(); |
| if (thread->is_Java_thread()) |
| return ((JavaThread*)thread)->thread_state() == _thread_in_vm; |
| else |
| return true; //something like this: thread->is_VM_thread(); |
| } |
| #endif //ASSERT |
| |
| void Dependencies::initialize(ciEnv* env) { |
| Arena* arena = env->arena(); |
| _oop_recorder = env->oop_recorder(); |
| _log = env->log(); |
| _dep_seen = new(arena) GrowableArray<int>(arena, 500, 0, 0); |
| DEBUG_ONLY(_deps[end_marker] = NULL); |
| for (int i = (int)FIRST_TYPE; i < (int)TYPE_LIMIT; i++) { |
| _deps[i] = new(arena) GrowableArray<ciBaseObject*>(arena, 10, 0, 0); |
| } |
| _content_bytes = NULL; |
| _size_in_bytes = (size_t)-1; |
| |
| assert(TYPE_LIMIT <= (1<<LG2_TYPE_LIMIT), "sanity"); |
| } |
| |
| void Dependencies::assert_evol_method(ciMethod* m) { |
| assert_common_1(evol_method, m); |
| } |
| |
| void Dependencies::assert_leaf_type(ciKlass* ctxk) { |
| if (ctxk->is_array_klass()) { |
| // As a special case, support this assertion on an array type, |
| // which reduces to an assertion on its element type. |
| // Note that this cannot be done with assertions that |
| // relate to concreteness or abstractness. |
| ciType* elemt = ctxk->as_array_klass()->base_element_type(); |
| if (!elemt->is_instance_klass()) return; // Ex: int[][] |
| ctxk = elemt->as_instance_klass(); |
| //if (ctxk->is_final()) return; // Ex: String[][] |
| } |
| check_ctxk(ctxk); |
| assert_common_1(leaf_type, ctxk); |
| } |
| |
| void Dependencies::assert_abstract_with_unique_concrete_subtype(ciKlass* ctxk, ciKlass* conck) { |
| check_ctxk_abstract(ctxk); |
| assert_common_2(abstract_with_unique_concrete_subtype, ctxk, conck); |
| } |
| |
| void Dependencies::assert_abstract_with_no_concrete_subtype(ciKlass* ctxk) { |
| check_ctxk_abstract(ctxk); |
| assert_common_1(abstract_with_no_concrete_subtype, ctxk); |
| } |
| |
| void Dependencies::assert_concrete_with_no_concrete_subtype(ciKlass* ctxk) { |
| check_ctxk_concrete(ctxk); |
| assert_common_1(concrete_with_no_concrete_subtype, ctxk); |
| } |
| |
| void Dependencies::assert_unique_concrete_method(ciKlass* ctxk, ciMethod* uniqm) { |
| check_ctxk(ctxk); |
| assert_common_2(unique_concrete_method, ctxk, uniqm); |
| } |
| |
| void Dependencies::assert_abstract_with_exclusive_concrete_subtypes(ciKlass* ctxk, ciKlass* k1, ciKlass* k2) { |
| check_ctxk(ctxk); |
| assert_common_3(abstract_with_exclusive_concrete_subtypes_2, ctxk, k1, k2); |
| } |
| |
| void Dependencies::assert_exclusive_concrete_methods(ciKlass* ctxk, ciMethod* m1, ciMethod* m2) { |
| check_ctxk(ctxk); |
| assert_common_3(exclusive_concrete_methods_2, ctxk, m1, m2); |
| } |
| |
| void Dependencies::assert_has_no_finalizable_subclasses(ciKlass* ctxk) { |
| check_ctxk(ctxk); |
| assert_common_1(no_finalizable_subclasses, ctxk); |
| } |
| |
| void Dependencies::assert_call_site_target_value(ciCallSite* call_site, ciMethodHandle* method_handle) { |
| check_ctxk(call_site->klass()); |
| assert_common_2(call_site_target_value, call_site, method_handle); |
| } |
| |
| // Helper function. If we are adding a new dep. under ctxk2, |
| // try to find an old dep. under a broader* ctxk1. If there is |
| // |
| bool Dependencies::maybe_merge_ctxk(GrowableArray<ciBaseObject*>* deps, |
| int ctxk_i, ciKlass* ctxk2) { |
| ciKlass* ctxk1 = deps->at(ctxk_i)->as_metadata()->as_klass(); |
| if (ctxk2->is_subtype_of(ctxk1)) { |
| return true; // success, and no need to change |
| } else if (ctxk1->is_subtype_of(ctxk2)) { |
| // new context class fully subsumes previous one |
| deps->at_put(ctxk_i, ctxk2); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| void Dependencies::assert_common_1(DepType dept, ciBaseObject* x) { |
| assert(dep_args(dept) == 1, "sanity"); |
| log_dependency(dept, x); |
| GrowableArray<ciBaseObject*>* deps = _deps[dept]; |
| |
| // see if the same (or a similar) dep is already recorded |
| if (note_dep_seen(dept, x)) { |
| assert(deps->find(x) >= 0, "sanity"); |
| } else { |
| deps->append(x); |
| } |
| } |
| |
| void Dependencies::assert_common_2(DepType dept, |
| ciBaseObject* x0, ciBaseObject* x1) { |
| assert(dep_args(dept) == 2, "sanity"); |
| log_dependency(dept, x0, x1); |
| GrowableArray<ciBaseObject*>* deps = _deps[dept]; |
| |
| // see if the same (or a similar) dep is already recorded |
| bool has_ctxk = has_explicit_context_arg(dept); |
| if (has_ctxk) { |
| assert(dep_context_arg(dept) == 0, "sanity"); |
| if (note_dep_seen(dept, x1)) { |
| // look in this bucket for redundant assertions |
| const int stride = 2; |
| for (int i = deps->length(); (i -= stride) >= 0; ) { |
| ciBaseObject* y1 = deps->at(i+1); |
| if (x1 == y1) { // same subject; check the context |
| if (maybe_merge_ctxk(deps, i+0, x0->as_metadata()->as_klass())) { |
| return; |
| } |
| } |
| } |
| } |
| } else { |
| assert(dep_implicit_context_arg(dept) == 0, "sanity"); |
| if (note_dep_seen(dept, x0) && note_dep_seen(dept, x1)) { |
| // look in this bucket for redundant assertions |
| const int stride = 2; |
| for (int i = deps->length(); (i -= stride) >= 0; ) { |
| ciBaseObject* y0 = deps->at(i+0); |
| ciBaseObject* y1 = deps->at(i+1); |
| if (x0 == y0 && x1 == y1) { |
| return; |
| } |
| } |
| } |
| } |
| |
| // append the assertion in the correct bucket: |
| deps->append(x0); |
| deps->append(x1); |
| } |
| |
| void Dependencies::assert_common_3(DepType dept, |
| ciKlass* ctxk, ciBaseObject* x, ciBaseObject* x2) { |
| assert(dep_context_arg(dept) == 0, "sanity"); |
| assert(dep_args(dept) == 3, "sanity"); |
| log_dependency(dept, ctxk, x, x2); |
| GrowableArray<ciBaseObject*>* deps = _deps[dept]; |
| |
| // try to normalize an unordered pair: |
| bool swap = false; |
| switch (dept) { |
| case abstract_with_exclusive_concrete_subtypes_2: |
| swap = (x->ident() > x2->ident() && x->as_metadata()->as_klass() != ctxk); |
| break; |
| case exclusive_concrete_methods_2: |
| swap = (x->ident() > x2->ident() && x->as_metadata()->as_method()->holder() != ctxk); |
| break; |
| } |
| if (swap) { ciBaseObject* t = x; x = x2; x2 = t; } |
| |
| // see if the same (or a similar) dep is already recorded |
| if (note_dep_seen(dept, x) && note_dep_seen(dept, x2)) { |
| // look in this bucket for redundant assertions |
| const int stride = 3; |
| for (int i = deps->length(); (i -= stride) >= 0; ) { |
| ciBaseObject* y = deps->at(i+1); |
| ciBaseObject* y2 = deps->at(i+2); |
| if (x == y && x2 == y2) { // same subjects; check the context |
| if (maybe_merge_ctxk(deps, i+0, ctxk)) { |
| return; |
| } |
| } |
| } |
| } |
| // append the assertion in the correct bucket: |
| deps->append(ctxk); |
| deps->append(x); |
| deps->append(x2); |
| } |
| |
| /// Support for encoding dependencies into an nmethod: |
| |
| void Dependencies::copy_to(nmethod* nm) { |
| address beg = nm->dependencies_begin(); |
| address end = nm->dependencies_end(); |
| guarantee(end - beg >= (ptrdiff_t) size_in_bytes(), "bad sizing"); |
| Copy::disjoint_words((HeapWord*) content_bytes(), |
| (HeapWord*) beg, |
| size_in_bytes() / sizeof(HeapWord)); |
| assert(size_in_bytes() % sizeof(HeapWord) == 0, "copy by words"); |
| } |
| |
| static int sort_dep(ciBaseObject** p1, ciBaseObject** p2, int narg) { |
| for (int i = 0; i < narg; i++) { |
| int diff = p1[i]->ident() - p2[i]->ident(); |
| if (diff != 0) return diff; |
| } |
| return 0; |
| } |
| static int sort_dep_arg_1(ciBaseObject** p1, ciBaseObject** p2) |
| { return sort_dep(p1, p2, 1); } |
| static int sort_dep_arg_2(ciBaseObject** p1, ciBaseObject** p2) |
| { return sort_dep(p1, p2, 2); } |
| static int sort_dep_arg_3(ciBaseObject** p1, ciBaseObject** p2) |
| { return sort_dep(p1, p2, 3); } |
| |
| void Dependencies::sort_all_deps() { |
| for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { |
| DepType dept = (DepType)deptv; |
| GrowableArray<ciBaseObject*>* deps = _deps[dept]; |
| if (deps->length() <= 1) continue; |
| switch (dep_args(dept)) { |
| case 1: deps->sort(sort_dep_arg_1, 1); break; |
| case 2: deps->sort(sort_dep_arg_2, 2); break; |
| case 3: deps->sort(sort_dep_arg_3, 3); break; |
| default: ShouldNotReachHere(); |
| } |
| } |
| } |
| |
| size_t Dependencies::estimate_size_in_bytes() { |
| size_t est_size = 100; |
| for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { |
| DepType dept = (DepType)deptv; |
| GrowableArray<ciBaseObject*>* deps = _deps[dept]; |
| est_size += deps->length()*2; // tags and argument(s) |
| } |
| return est_size; |
| } |
| |
| ciKlass* Dependencies::ctxk_encoded_as_null(DepType dept, ciBaseObject* x) { |
| switch (dept) { |
| case abstract_with_exclusive_concrete_subtypes_2: |
| return x->as_metadata()->as_klass(); |
| case unique_concrete_method: |
| case exclusive_concrete_methods_2: |
| return x->as_metadata()->as_method()->holder(); |
| } |
| return NULL; // let NULL be NULL |
| } |
| |
| Klass* Dependencies::ctxk_encoded_as_null(DepType dept, Metadata* x) { |
| assert(must_be_in_vm(), "raw oops here"); |
| switch (dept) { |
| case abstract_with_exclusive_concrete_subtypes_2: |
| assert(x->is_klass(), "sanity"); |
| return (Klass*) x; |
| case unique_concrete_method: |
| case exclusive_concrete_methods_2: |
| assert(x->is_method(), "sanity"); |
| return ((Method*)x)->method_holder(); |
| } |
| return NULL; // let NULL be NULL |
| } |
| |
| void Dependencies::encode_content_bytes() { |
| sort_all_deps(); |
| |
| // cast is safe, no deps can overflow INT_MAX |
| CompressedWriteStream bytes((int)estimate_size_in_bytes()); |
| |
| for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { |
| DepType dept = (DepType)deptv; |
| GrowableArray<ciBaseObject*>* deps = _deps[dept]; |
| if (deps->length() == 0) continue; |
| int stride = dep_args(dept); |
| int ctxkj = dep_context_arg(dept); // -1 if no context arg |
| assert(stride > 0, "sanity"); |
| for (int i = 0; i < deps->length(); i += stride) { |
| jbyte code_byte = (jbyte)dept; |
| int skipj = -1; |
| if (ctxkj >= 0 && ctxkj+1 < stride) { |
| ciKlass* ctxk = deps->at(i+ctxkj+0)->as_metadata()->as_klass(); |
| ciBaseObject* x = deps->at(i+ctxkj+1); // following argument |
| if (ctxk == ctxk_encoded_as_null(dept, x)) { |
| skipj = ctxkj; // we win: maybe one less oop to keep track of |
| code_byte |= default_context_type_bit; |
| } |
| } |
| bytes.write_byte(code_byte); |
| for (int j = 0; j < stride; j++) { |
| if (j == skipj) continue; |
| ciBaseObject* v = deps->at(i+j); |
| int idx; |
| if (v->is_object()) { |
| idx = _oop_recorder->find_index(v->as_object()->constant_encoding()); |
| } else { |
| ciMetadata* meta = v->as_metadata(); |
| idx = _oop_recorder->find_index(meta->constant_encoding()); |
| } |
| bytes.write_int(idx); |
| } |
| } |
| } |
| |
| // write a sentinel byte to mark the end |
| bytes.write_byte(end_marker); |
| |
| // round it out to a word boundary |
| while (bytes.position() % sizeof(HeapWord) != 0) { |
| bytes.write_byte(end_marker); |
| } |
| |
| // check whether the dept byte encoding really works |
| assert((jbyte)default_context_type_bit != 0, "byte overflow"); |
| |
| _content_bytes = bytes.buffer(); |
| _size_in_bytes = bytes.position(); |
| } |
| |
| |
| const char* Dependencies::_dep_name[TYPE_LIMIT] = { |
| "end_marker", |
| "evol_method", |
| "leaf_type", |
| "abstract_with_unique_concrete_subtype", |
| "abstract_with_no_concrete_subtype", |
| "concrete_with_no_concrete_subtype", |
| "unique_concrete_method", |
| "abstract_with_exclusive_concrete_subtypes_2", |
| "exclusive_concrete_methods_2", |
| "no_finalizable_subclasses", |
| "call_site_target_value" |
| }; |
| |
| int Dependencies::_dep_args[TYPE_LIMIT] = { |
| -1,// end_marker |
| 1, // evol_method m |
| 1, // leaf_type ctxk |
| 2, // abstract_with_unique_concrete_subtype ctxk, k |
| 1, // abstract_with_no_concrete_subtype ctxk |
| 1, // concrete_with_no_concrete_subtype ctxk |
| 2, // unique_concrete_method ctxk, m |
| 3, // unique_concrete_subtypes_2 ctxk, k1, k2 |
| 3, // unique_concrete_methods_2 ctxk, m1, m2 |
| 1, // no_finalizable_subclasses ctxk |
| 2 // call_site_target_value call_site, method_handle |
| }; |
| |
| const char* Dependencies::dep_name(Dependencies::DepType dept) { |
| if (!dept_in_mask(dept, all_types)) return "?bad-dep?"; |
| return _dep_name[dept]; |
| } |
| |
| int Dependencies::dep_args(Dependencies::DepType dept) { |
| if (!dept_in_mask(dept, all_types)) return -1; |
| return _dep_args[dept]; |
| } |
| |
| void Dependencies::check_valid_dependency_type(DepType dept) { |
| guarantee(FIRST_TYPE <= dept && dept < TYPE_LIMIT, err_msg("invalid dependency type: %d", (int) dept)); |
| } |
| |
| // for the sake of the compiler log, print out current dependencies: |
| void Dependencies::log_all_dependencies() { |
| if (log() == NULL) return; |
| ciBaseObject* args[max_arg_count]; |
| for (int deptv = (int)FIRST_TYPE; deptv < (int)TYPE_LIMIT; deptv++) { |
| DepType dept = (DepType)deptv; |
| GrowableArray<ciBaseObject*>* deps = _deps[dept]; |
| if (deps->length() == 0) continue; |
| int stride = dep_args(dept); |
| for (int i = 0; i < deps->length(); i += stride) { |
| for (int j = 0; j < stride; j++) { |
| // flush out the identities before printing |
| args[j] = deps->at(i+j); |
| } |
| write_dependency_to(log(), dept, stride, args); |
| } |
| } |
| } |
| |
| void Dependencies::write_dependency_to(CompileLog* log, |
| DepType dept, |
| int nargs, DepArgument args[], |
| Klass* witness) { |
| if (log == NULL) { |
| return; |
| } |
| ciEnv* env = ciEnv::current(); |
| ciBaseObject* ciargs[max_arg_count]; |
| assert(nargs <= max_arg_count, "oob"); |
| for (int j = 0; j < nargs; j++) { |
| if (args[j].is_oop()) { |
| ciargs[j] = env->get_object(args[j].oop_value()); |
| } else { |
| ciargs[j] = env->get_metadata(args[j].metadata_value()); |
| } |
| } |
| Dependencies::write_dependency_to(log, dept, nargs, ciargs, witness); |
| } |
| |
| void Dependencies::write_dependency_to(CompileLog* log, |
| DepType dept, |
| int nargs, ciBaseObject* args[], |
| Klass* witness) { |
| if (log == NULL) return; |
| assert(nargs <= max_arg_count, "oob"); |
| int argids[max_arg_count]; |
| int ctxkj = dep_context_arg(dept); // -1 if no context arg |
| int j; |
| for (j = 0; j < nargs; j++) { |
| if (args[j]->is_object()) { |
| argids[j] = log->identify(args[j]->as_object()); |
| } else { |
| argids[j] = log->identify(args[j]->as_metadata()); |
| } |
| } |
| if (witness != NULL) { |
| log->begin_elem("dependency_failed"); |
| } else { |
| log->begin_elem("dependency"); |
| } |
| log->print(" type='%s'", dep_name(dept)); |
| if (ctxkj >= 0) { |
| log->print(" ctxk='%d'", argids[ctxkj]); |
| } |
| // write remaining arguments, if any. |
| for (j = 0; j < nargs; j++) { |
| if (j == ctxkj) continue; // already logged |
| if (j == 1) { |
| log->print( " x='%d'", argids[j]); |
| } else { |
| log->print(" x%d='%d'", j, argids[j]); |
| } |
| } |
| if (witness != NULL) { |
| log->object("witness", witness); |
| log->stamp(); |
| } |
| log->end_elem(); |
| } |
| |
| void Dependencies::write_dependency_to(xmlStream* xtty, |
| DepType dept, |
| int nargs, DepArgument args[], |
| Klass* witness) { |
| if (xtty == NULL) return; |
| ttyLocker ttyl; |
| int ctxkj = dep_context_arg(dept); // -1 if no context arg |
| if (witness != NULL) { |
| xtty->begin_elem("dependency_failed"); |
| } else { |
| xtty->begin_elem("dependency"); |
| } |
| xtty->print(" type='%s'", dep_name(dept)); |
| if (ctxkj >= 0) { |
| xtty->object("ctxk", args[ctxkj].metadata_value()); |
| } |
| // write remaining arguments, if any. |
| for (int j = 0; j < nargs; j++) { |
| if (j == ctxkj) continue; // already logged |
| if (j == 1) { |
| if (args[j].is_oop()) { |
| xtty->object("x", args[j].oop_value()); |
| } else { |
| xtty->object("x", args[j].metadata_value()); |
| } |
| } else { |
| char xn[10]; sprintf(xn, "x%d", j); |
| if (args[j].is_oop()) { |
| xtty->object(xn, args[j].oop_value()); |
| } else { |
| xtty->object(xn, args[j].metadata_value()); |
| } |
| } |
| } |
| if (witness != NULL) { |
| xtty->object("witness", witness); |
| xtty->stamp(); |
| } |
| xtty->end_elem(); |
| } |
| |
| void Dependencies::print_dependency(DepType dept, int nargs, DepArgument args[], |
| Klass* witness) { |
| ResourceMark rm; |
| ttyLocker ttyl; // keep the following output all in one block |
| tty->print_cr("%s of type %s", |
| (witness == NULL)? "Dependency": "Failed dependency", |
| dep_name(dept)); |
| // print arguments |
| int ctxkj = dep_context_arg(dept); // -1 if no context arg |
| for (int j = 0; j < nargs; j++) { |
| DepArgument arg = args[j]; |
| bool put_star = false; |
| if (arg.is_null()) continue; |
| const char* what; |
| if (j == ctxkj) { |
| assert(arg.is_metadata(), "must be"); |
| what = "context"; |
| put_star = !Dependencies::is_concrete_klass((Klass*)arg.metadata_value()); |
| } else if (arg.is_method()) { |
| what = "method "; |
| put_star = !Dependencies::is_concrete_method((Method*)arg.metadata_value()); |
| } else if (arg.is_klass()) { |
| what = "class "; |
| } else { |
| what = "object "; |
| } |
| tty->print(" %s = %s", what, (put_star? "*": "")); |
| if (arg.is_klass()) |
| tty->print("%s", ((Klass*)arg.metadata_value())->external_name()); |
| else if (arg.is_method()) |
| ((Method*)arg.metadata_value())->print_value(); |
| else |
| ShouldNotReachHere(); // Provide impl for this type. |
| tty->cr(); |
| } |
| if (witness != NULL) { |
| bool put_star = !Dependencies::is_concrete_klass(witness); |
| tty->print_cr(" witness = %s%s", |
| (put_star? "*": ""), |
| witness->external_name()); |
| } |
| } |
| |
| void Dependencies::DepStream::log_dependency(Klass* witness) { |
| if (_deps == NULL && xtty == NULL) return; // fast cutout for runtime |
| ResourceMark rm; |
| int nargs = argument_count(); |
| DepArgument args[max_arg_count]; |
| for (int j = 0; j < nargs; j++) { |
| if (type() == call_site_target_value) { |
| args[j] = argument_oop(j); |
| } else { |
| args[j] = argument(j); |
| } |
| } |
| if (_deps != NULL && _deps->log() != NULL) { |
| Dependencies::write_dependency_to(_deps->log(), |
| type(), nargs, args, witness); |
| } else { |
| Dependencies::write_dependency_to(xtty, |
| type(), nargs, args, witness); |
| } |
| } |
| |
| void Dependencies::DepStream::print_dependency(Klass* witness, bool verbose) { |
| int nargs = argument_count(); |
| DepArgument args[max_arg_count]; |
| for (int j = 0; j < nargs; j++) { |
| args[j] = argument(j); |
| } |
| Dependencies::print_dependency(type(), nargs, args, witness); |
| if (verbose) { |
| if (_code != NULL) { |
| tty->print(" code: "); |
| _code->print_value_on(tty); |
| tty->cr(); |
| } |
| } |
| } |
| |
| |
| /// Dependency stream support (decodes dependencies from an nmethod): |
| |
| #ifdef ASSERT |
| void Dependencies::DepStream::initial_asserts(size_t byte_limit) { |
| assert(must_be_in_vm(), "raw oops here"); |
| _byte_limit = byte_limit; |
| _type = (DepType)(end_marker-1); // defeat "already at end" assert |
| assert((_code!=NULL) + (_deps!=NULL) == 1, "one or t'other"); |
| } |
| #endif //ASSERT |
| |
| bool Dependencies::DepStream::next() { |
| assert(_type != end_marker, "already at end"); |
| if (_bytes.position() == 0 && _code != NULL |
| && _code->dependencies_size() == 0) { |
| // Method has no dependencies at all. |
| return false; |
| } |
| int code_byte = (_bytes.read_byte() & 0xFF); |
| if (code_byte == end_marker) { |
| DEBUG_ONLY(_type = end_marker); |
| return false; |
| } else { |
| int ctxk_bit = (code_byte & Dependencies::default_context_type_bit); |
| code_byte -= ctxk_bit; |
| DepType dept = (DepType)code_byte; |
| _type = dept; |
| Dependencies::check_valid_dependency_type(dept); |
| int stride = _dep_args[dept]; |
| assert(stride == dep_args(dept), "sanity"); |
| int skipj = -1; |
| if (ctxk_bit != 0) { |
| skipj = 0; // currently the only context argument is at zero |
| assert(skipj == dep_context_arg(dept), "zero arg always ctxk"); |
| } |
| for (int j = 0; j < stride; j++) { |
| _xi[j] = (j == skipj)? 0: _bytes.read_int(); |
| } |
| DEBUG_ONLY(_xi[stride] = -1); // help detect overruns |
| return true; |
| } |
| } |
| |
| inline Metadata* Dependencies::DepStream::recorded_metadata_at(int i) { |
| Metadata* o = NULL; |
| if (_code != NULL) { |
| o = _code->metadata_at(i); |
| } else { |
| o = _deps->oop_recorder()->metadata_at(i); |
| } |
| return o; |
| } |
| |
| inline oop Dependencies::DepStream::recorded_oop_at(int i) { |
| return (_code != NULL) |
| ? _code->oop_at(i) |
| : JNIHandles::resolve(_deps->oop_recorder()->oop_at(i)); |
| } |
| |
| Metadata* Dependencies::DepStream::argument(int i) { |
| Metadata* result = recorded_metadata_at(argument_index(i)); |
| |
| if (result == NULL) { // Explicit context argument can be compressed |
| int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg |
| if (ctxkj >= 0 && i == ctxkj && ctxkj+1 < argument_count()) { |
| result = ctxk_encoded_as_null(type(), argument(ctxkj+1)); |
| } |
| } |
| |
| assert(result == NULL || result->is_klass() || result->is_method(), "must be"); |
| return result; |
| } |
| |
| /** |
| * Returns a unique identifier for each dependency argument. |
| */ |
| uintptr_t Dependencies::DepStream::get_identifier(int i) { |
| if (has_oop_argument()) { |
| return (uintptr_t)(oopDesc*)argument_oop(i); |
| } else { |
| return (uintptr_t)argument(i); |
| } |
| } |
| |
| oop Dependencies::DepStream::argument_oop(int i) { |
| oop result = recorded_oop_at(argument_index(i)); |
| assert(result == NULL || result->is_oop(), "must be"); |
| return result; |
| } |
| |
| Klass* Dependencies::DepStream::context_type() { |
| assert(must_be_in_vm(), "raw oops here"); |
| |
| // Most dependencies have an explicit context type argument. |
| { |
| int ctxkj = dep_context_arg(type()); // -1 if no explicit context arg |
| if (ctxkj >= 0) { |
| Metadata* k = argument(ctxkj); |
| assert(k != NULL && k->is_klass(), "type check"); |
| return (Klass*)k; |
| } |
| } |
| |
| // Some dependencies are using the klass of the first object |
| // argument as implicit context type (e.g. call_site_target_value). |
| { |
| int ctxkj = dep_implicit_context_arg(type()); |
| if (ctxkj >= 0) { |
| Klass* k = argument_oop(ctxkj)->klass(); |
| assert(k != NULL && k->is_klass(), "type check"); |
| return (Klass*) k; |
| } |
| } |
| |
| // And some dependencies don't have a context type at all, |
| // e.g. evol_method. |
| return NULL; |
| } |
| |
| // ----------------- DependencySignature -------------------------------------- |
| bool DependencySignature::equals(const DependencySignature& sig) const { |
| if (type() != sig.type()) { |
| return false; |
| } |
| |
| if (args_count() != sig.args_count()) { |
| return false; |
| } |
| |
| for (int i = 0; i < sig.args_count(); i++) { |
| if (arg(i) != sig.arg(i)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| |
| // ----------------- DependencySignatureBuffer -------------------------------------- |
| DependencySignatureBuffer::DependencySignatureBuffer() { |
| _signatures = NEW_RESOURCE_ARRAY(GrowableArray<DependencySignature*>*, Dependencies::TYPE_LIMIT); |
| memset(_signatures, 0, sizeof(DependencySignature*) * Dependencies::TYPE_LIMIT); |
| } |
| |
| /* Check if arguments are identical. Two dependency signatures are considered |
| * identical, if the type as well as all argument identifiers are identical. |
| * If the dependency has not already been checked, the dependency signature is |
| * added to the checked dependencies of the same type. The function returns |
| * false, which causes the dependency to be checked in the caller. |
| */ |
| bool DependencySignatureBuffer::add_if_missing(const DependencySignature& sig) { |
| const int index = sig.type(); |
| GrowableArray<DependencySignature*>* buffer = _signatures[index]; |
| if (buffer == NULL) { |
| buffer = new GrowableArray<DependencySignature*>(); |
| _signatures[index] = buffer; |
| } |
| |
| // Check if we have already checked the dependency |
| for (int i = 0; i < buffer->length(); i++) { |
| DependencySignature* checked_signature = buffer->at(i); |
| if (checked_signature->equals(sig)) { |
| return true; |
| } |
| } |
| buffer->append((DependencySignature*)&sig); |
| return false; |
| } |
| |
| |
| /// Checking dependencies: |
| |
| // This hierarchy walker inspects subtypes of a given type, |
| // trying to find a "bad" class which breaks a dependency. |
| // Such a class is called a "witness" to the broken dependency. |
| // While searching around, we ignore "participants", which |
| // are already known to the dependency. |
| class ClassHierarchyWalker { |
| public: |
| enum { PARTICIPANT_LIMIT = 3 }; |
| |
| private: |
| // optional method descriptor to check for: |
| Symbol* _name; |
| Symbol* _signature; |
| |
| // special classes which are not allowed to be witnesses: |
| Klass* _participants[PARTICIPANT_LIMIT+1]; |
| int _num_participants; |
| |
| // cache of method lookups |
| Method* _found_methods[PARTICIPANT_LIMIT+1]; |
| |
| // if non-zero, tells how many witnesses to convert to participants |
| int _record_witnesses; |
| |
| void initialize(Klass* participant) { |
| _record_witnesses = 0; |
| _participants[0] = participant; |
| _found_methods[0] = NULL; |
| _num_participants = 0; |
| if (participant != NULL) { |
| // Terminating NULL. |
| _participants[1] = NULL; |
| _found_methods[1] = NULL; |
| _num_participants = 1; |
| } |
| } |
| |
| void initialize_from_method(Method* m) { |
| assert(m != NULL && m->is_method(), "sanity"); |
| _name = m->name(); |
| _signature = m->signature(); |
| } |
| |
| public: |
| // The walker is initialized to recognize certain methods and/or types |
| // as friendly participants. |
| ClassHierarchyWalker(Klass* participant, Method* m) { |
| initialize_from_method(m); |
| initialize(participant); |
| } |
| ClassHierarchyWalker(Method* m) { |
| initialize_from_method(m); |
| initialize(NULL); |
| } |
| ClassHierarchyWalker(Klass* participant = NULL) { |
| _name = NULL; |
| _signature = NULL; |
| initialize(participant); |
| } |
| |
| // This is common code for two searches: One for concrete subtypes, |
| // the other for concrete method implementations and overrides. |
| bool doing_subtype_search() { |
| return _name == NULL; |
| } |
| |
| int num_participants() { return _num_participants; } |
| Klass* participant(int n) { |
| assert((uint)n <= (uint)_num_participants, "oob"); |
| return _participants[n]; |
| } |
| |
| // Note: If n==num_participants, returns NULL. |
| Method* found_method(int n) { |
| assert((uint)n <= (uint)_num_participants, "oob"); |
| Method* fm = _found_methods[n]; |
| assert(n == _num_participants || fm != NULL, "proper usage"); |
| assert(fm == NULL || fm->method_holder() == _participants[n], "sanity"); |
| return fm; |
| } |
| |
| #ifdef ASSERT |
| // Assert that m is inherited into ctxk, without intervening overrides. |
| // (May return true even if this is not true, in corner cases where we punt.) |
| bool check_method_context(Klass* ctxk, Method* m) { |
| if (m->method_holder() == ctxk) |
| return true; // Quick win. |
| if (m->is_private()) |
| return false; // Quick lose. Should not happen. |
| if (!(m->is_public() || m->is_protected())) |
| // The override story is complex when packages get involved. |
| return true; // Must punt the assertion to true. |
| Klass* k = ctxk; |
| Method* lm = k->lookup_method(m->name(), m->signature()); |
| if (lm == NULL && k->oop_is_instance()) { |
| // It might be an interface method |
| lm = ((InstanceKlass*)k)->lookup_method_in_ordered_interfaces(m->name(), |
| m->signature()); |
| } |
| if (lm == m) |
| // Method m is inherited into ctxk. |
| return true; |
| if (lm != NULL) { |
| if (!(lm->is_public() || lm->is_protected())) { |
| // Method is [package-]private, so the override story is complex. |
| return true; // Must punt the assertion to true. |
| } |
| if (lm->is_static()) { |
| // Static methods don't override non-static so punt |
| return true; |
| } |
| if ( !Dependencies::is_concrete_method(lm) |
| && !Dependencies::is_concrete_method(m) |
| && lm->method_holder()->is_subtype_of(m->method_holder())) |
| // Method m is overridden by lm, but both are non-concrete. |
| return true; |
| } |
| ResourceMark rm; |
| tty->print_cr("Dependency method not found in the associated context:"); |
| tty->print_cr(" context = %s", ctxk->external_name()); |
| tty->print( " method = "); m->print_short_name(tty); tty->cr(); |
| if (lm != NULL) { |
| tty->print( " found = "); lm->print_short_name(tty); tty->cr(); |
| } |
| return false; |
| } |
| #endif |
| |
| void add_participant(Klass* participant) { |
| assert(_num_participants + _record_witnesses < PARTICIPANT_LIMIT, "oob"); |
| int np = _num_participants++; |
| _participants[np] = participant; |
| _participants[np+1] = NULL; |
| _found_methods[np+1] = NULL; |
| } |
| |
| void record_witnesses(int add) { |
| if (add > PARTICIPANT_LIMIT) add = PARTICIPANT_LIMIT; |
| assert(_num_participants + add < PARTICIPANT_LIMIT, "oob"); |
| _record_witnesses = add; |
| } |
| |
| bool is_witness(Klass* k) { |
| if (doing_subtype_search()) { |
| return Dependencies::is_concrete_klass(k); |
| } else { |
| Method* m = InstanceKlass::cast(k)->find_method(_name, _signature); |
| if (m == NULL || !Dependencies::is_concrete_method(m)) return false; |
| _found_methods[_num_participants] = m; |
| // Note: If add_participant(k) is called, |
| // the method m will already be memoized for it. |
| return true; |
| } |
| } |
| |
| bool is_participant(Klass* k) { |
| if (k == _participants[0]) { |
| return true; |
| } else if (_num_participants <= 1) { |
| return false; |
| } else { |
| return in_list(k, &_participants[1]); |
| } |
| } |
| bool ignore_witness(Klass* witness) { |
| if (_record_witnesses == 0) { |
| return false; |
| } else { |
| --_record_witnesses; |
| add_participant(witness); |
| return true; |
| } |
| } |
| static bool in_list(Klass* x, Klass** list) { |
| for (int i = 0; ; i++) { |
| Klass* y = list[i]; |
| if (y == NULL) break; |
| if (y == x) return true; |
| } |
| return false; // not in list |
| } |
| |
| private: |
| // the actual search method: |
| Klass* find_witness_anywhere(Klass* context_type, |
| bool participants_hide_witnesses, |
| bool top_level_call = true); |
| // the spot-checking version: |
| Klass* find_witness_in(KlassDepChange& changes, |
| Klass* context_type, |
| bool participants_hide_witnesses); |
| public: |
| Klass* find_witness_subtype(Klass* context_type, KlassDepChange* changes = NULL) { |
| assert(doing_subtype_search(), "must set up a subtype search"); |
| // When looking for unexpected concrete types, |
| // do not look beneath expected ones. |
| const bool participants_hide_witnesses = true; |
| // CX > CC > C' is OK, even if C' is new. |
| // CX > { CC, C' } is not OK if C' is new, and C' is the witness. |
| if (changes != NULL) { |
| return find_witness_in(*changes, context_type, participants_hide_witnesses); |
| } else { |
| return find_witness_anywhere(context_type, participants_hide_witnesses); |
| } |
| } |
| Klass* find_witness_definer(Klass* context_type, KlassDepChange* changes = NULL) { |
| assert(!doing_subtype_search(), "must set up a method definer search"); |
| // When looking for unexpected concrete methods, |
| // look beneath expected ones, to see if there are overrides. |
| const bool participants_hide_witnesses = true; |
| // CX.m > CC.m > C'.m is not OK, if C'.m is new, and C' is the witness. |
| if (changes != NULL) { |
| return find_witness_in(*changes, context_type, !participants_hide_witnesses); |
| } else { |
| return find_witness_anywhere(context_type, !participants_hide_witnesses); |
| } |
| } |
| }; |
| |
| #ifndef PRODUCT |
| static int deps_find_witness_calls = 0; |
| static int deps_find_witness_steps = 0; |
| static int deps_find_witness_recursions = 0; |
| static int deps_find_witness_singles = 0; |
| static int deps_find_witness_print = 0; // set to -1 to force a final print |
| static bool count_find_witness_calls() { |
| if (TraceDependencies || LogCompilation) { |
| int pcount = deps_find_witness_print + 1; |
| bool final_stats = (pcount == 0); |
| bool initial_call = (pcount == 1); |
| bool occasional_print = ((pcount & ((1<<10) - 1)) == 0); |
| if (pcount < 0) pcount = 1; // crude overflow protection |
| deps_find_witness_print = pcount; |
| if (VerifyDependencies && initial_call) { |
| tty->print_cr("Warning: TraceDependencies results may be inflated by VerifyDependencies"); |
| } |
| if (occasional_print || final_stats) { |
| // Every now and then dump a little info about dependency searching. |
| if (xtty != NULL) { |
| ttyLocker ttyl; |
| xtty->elem("deps_find_witness calls='%d' steps='%d' recursions='%d' singles='%d'", |
| deps_find_witness_calls, |
| deps_find_witness_steps, |
| deps_find_witness_recursions, |
| deps_find_witness_singles); |
| } |
| if (final_stats || (TraceDependencies && WizardMode)) { |
| ttyLocker ttyl; |
| tty->print_cr("Dependency check (find_witness) " |
| "calls=%d, steps=%d (avg=%.1f), recursions=%d, singles=%d", |
| deps_find_witness_calls, |
| deps_find_witness_steps, |
| (double)deps_find_witness_steps / deps_find_witness_calls, |
| deps_find_witness_recursions, |
| deps_find_witness_singles); |
| } |
| } |
| return true; |
| } |
| return false; |
| } |
| #else |
| #define count_find_witness_calls() (0) |
| #endif //PRODUCT |
| |
| |
| Klass* ClassHierarchyWalker::find_witness_in(KlassDepChange& changes, |
| Klass* context_type, |
| bool participants_hide_witnesses) { |
| assert(changes.involves_context(context_type), "irrelevant dependency"); |
| Klass* new_type = changes.new_type(); |
| |
| (void)count_find_witness_calls(); |
| NOT_PRODUCT(deps_find_witness_singles++); |
| |
| // Current thread must be in VM (not native mode, as in CI): |
| assert(must_be_in_vm(), "raw oops here"); |
| // Must not move the class hierarchy during this check: |
| assert_locked_or_safepoint(Compile_lock); |
| |
| int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); |
| if (nof_impls > 1) { |
| // Avoid this case: *I.m > { A.m, C }; B.m > C |
| // %%% Until this is fixed more systematically, bail out. |
| // See corresponding comment in find_witness_anywhere. |
| return context_type; |
| } |
| |
| assert(!is_participant(new_type), "only old classes are participants"); |
| if (participants_hide_witnesses) { |
| // If the new type is a subtype of a participant, we are done. |
| for (int i = 0; i < num_participants(); i++) { |
| Klass* part = participant(i); |
| if (part == NULL) continue; |
| assert(changes.involves_context(part) == new_type->is_subtype_of(part), |
| "correct marking of participants, b/c new_type is unique"); |
| if (changes.involves_context(part)) { |
| // new guy is protected from this check by previous participant |
| return NULL; |
| } |
| } |
| } |
| |
| if (is_witness(new_type) && |
| !ignore_witness(new_type)) { |
| return new_type; |
| } |
| |
| return NULL; |
| } |
| |
| |
| // Walk hierarchy under a context type, looking for unexpected types. |
| // Do not report participant types, and recursively walk beneath |
| // them only if participants_hide_witnesses is false. |
| // If top_level_call is false, skip testing the context type, |
| // because the caller has already considered it. |
| Klass* ClassHierarchyWalker::find_witness_anywhere(Klass* context_type, |
| bool participants_hide_witnesses, |
| bool top_level_call) { |
| // Current thread must be in VM (not native mode, as in CI): |
| assert(must_be_in_vm(), "raw oops here"); |
| // Must not move the class hierarchy during this check: |
| assert_locked_or_safepoint(Compile_lock); |
| |
| bool do_counts = count_find_witness_calls(); |
| |
| // Check the root of the sub-hierarchy first. |
| if (top_level_call) { |
| if (do_counts) { |
| NOT_PRODUCT(deps_find_witness_calls++); |
| NOT_PRODUCT(deps_find_witness_steps++); |
| } |
| if (is_participant(context_type)) { |
| if (participants_hide_witnesses) return NULL; |
| // else fall through to search loop... |
| } else if (is_witness(context_type) && !ignore_witness(context_type)) { |
| // The context is an abstract class or interface, to start with. |
| return context_type; |
| } |
| } |
| |
| // Now we must check each implementor and each subclass. |
| // Use a short worklist to avoid blowing the stack. |
| // Each worklist entry is a *chain* of subklass siblings to process. |
| const int CHAINMAX = 100; // >= 1 + InstanceKlass::implementors_limit |
| Klass* chains[CHAINMAX]; |
| int chaini = 0; // index into worklist |
| Klass* chain; // scratch variable |
| #define ADD_SUBCLASS_CHAIN(k) { \ |
| assert(chaini < CHAINMAX, "oob"); \ |
| chain = InstanceKlass::cast(k)->subklass(); \ |
| if (chain != NULL) chains[chaini++] = chain; } |
| |
| // Look for non-abstract subclasses. |
| // (Note: Interfaces do not have subclasses.) |
| ADD_SUBCLASS_CHAIN(context_type); |
| |
| // If it is an interface, search its direct implementors. |
| // (Their subclasses are additional indirect implementors. |
| // See InstanceKlass::add_implementor.) |
| // (Note: nof_implementors is always zero for non-interfaces.) |
| int nof_impls = InstanceKlass::cast(context_type)->nof_implementors(); |
| if (nof_impls > 1) { |
| // Avoid this case: *I.m > { A.m, C }; B.m > C |
| // Here, I.m has 2 concrete implementations, but m appears unique |
| // as A.m, because the search misses B.m when checking C. |
| // The inherited method B.m was getting missed by the walker |
| // when interface 'I' was the starting point. |
| // %%% Until this is fixed more systematically, bail out. |
| // (Old CHA had the same limitation.) |
| return context_type; |
| } |
| if (nof_impls > 0) { |
| Klass* impl = InstanceKlass::cast(context_type)->implementor(); |
| assert(impl != NULL, "just checking"); |
| // If impl is the same as the context_type, then more than one |
| // implementor has seen. No exact info in this case. |
| if (impl == context_type) { |
| return context_type; // report an inexact witness to this sad affair |
| } |
| if (do_counts) |
| { NOT_PRODUCT(deps_find_witness_steps++); } |
| if (is_participant(impl)) { |
| if (!participants_hide_witnesses) { |
| ADD_SUBCLASS_CHAIN(impl); |
| } |
| } else if (is_witness(impl) && !ignore_witness(impl)) { |
| return impl; |
| } else { |
| ADD_SUBCLASS_CHAIN(impl); |
| } |
| } |
| |
| // Recursively process each non-trivial sibling chain. |
| while (chaini > 0) { |
| Klass* chain = chains[--chaini]; |
| for (Klass* sub = chain; sub != NULL; sub = sub->next_sibling()) { |
| if (do_counts) { NOT_PRODUCT(deps_find_witness_steps++); } |
| if (is_participant(sub)) { |
| if (participants_hide_witnesses) continue; |
| // else fall through to process this guy's subclasses |
| } else if (is_witness(sub) && !ignore_witness(sub)) { |
| return sub; |
| } |
| if (chaini < (VerifyDependencies? 2: CHAINMAX)) { |
| // Fast path. (Partially disabled if VerifyDependencies.) |
| ADD_SUBCLASS_CHAIN(sub); |
| } else { |
| // Worklist overflow. Do a recursive call. Should be rare. |
| // The recursive call will have its own worklist, of course. |
| // (Note that sub has already been tested, so that there is |
| // no need for the recursive call to re-test. That's handy, |
| // since the recursive call sees sub as the context_type.) |
| if (do_counts) { NOT_PRODUCT(deps_find_witness_recursions++); } |
| Klass* witness = find_witness_anywhere(sub, |
| participants_hide_witnesses, |
| /*top_level_call=*/ false); |
| if (witness != NULL) return witness; |
| } |
| } |
| } |
| |
| // No witness found. The dependency remains unbroken. |
| return NULL; |
| #undef ADD_SUBCLASS_CHAIN |
| } |
| |
| |
| bool Dependencies::is_concrete_klass(Klass* k) { |
| if (k->is_abstract()) return false; |
| // %%% We could treat classes which are concrete but |
| // have not yet been instantiated as virtually abstract. |
| // This would require a deoptimization barrier on first instantiation. |
| //if (k->is_not_instantiated()) return false; |
| return true; |
| } |
| |
| bool Dependencies::is_concrete_method(Method* m) { |
| // Statics are irrelevant to virtual call sites. |
| if (m->is_static()) return false; |
| |
| // We could also return false if m does not yet appear to be |
| // executed, if the VM version supports this distinction also. |
| // Default methods are considered "concrete" as well. |
| return !m->is_abstract() && |
| !m->is_overpass(); // error functions aren't concrete |
| } |
| |
| |
| Klass* Dependencies::find_finalizable_subclass(Klass* k) { |
| if (k->is_interface()) return NULL; |
| if (k->has_finalizer()) return k; |
| k = k->subklass(); |
| while (k != NULL) { |
| Klass* result = find_finalizable_subclass(k); |
| if (result != NULL) return result; |
| k = k->next_sibling(); |
| } |
| return NULL; |
| } |
| |
| |
| bool Dependencies::is_concrete_klass(ciInstanceKlass* k) { |
| if (k->is_abstract()) return false; |
| // We could also return false if k does not yet appear to be |
| // instantiated, if the VM version supports this distinction also. |
| //if (k->is_not_instantiated()) return false; |
| return true; |
| } |
| |
| bool Dependencies::is_concrete_method(ciMethod* m) { |
| // Statics are irrelevant to virtual call sites. |
| if (m->is_static()) return false; |
| |
| // We could also return false if m does not yet appear to be |
| // executed, if the VM version supports this distinction also. |
| return !m->is_abstract(); |
| } |
| |
| |
| bool Dependencies::has_finalizable_subclass(ciInstanceKlass* k) { |
| return k->has_finalizable_subclass(); |
| } |
| |
| |
| // Any use of the contents (bytecodes) of a method must be |
| // marked by an "evol_method" dependency, if those contents |
| // can change. (Note: A method is always dependent on itself.) |
| Klass* Dependencies::check_evol_method(Method* m) { |
| assert(must_be_in_vm(), "raw oops here"); |
| // Did somebody do a JVMTI RedefineClasses while our backs were turned? |
| // Or is there a now a breakpoint? |
| // (Assumes compiled code cannot handle bkpts; change if UseFastBreakpoints.) |
| if (m->is_old() |
| || m->number_of_breakpoints() > 0) { |
| return m->method_holder(); |
| } else { |
| return NULL; |
| } |
| } |
| |
| // This is a strong assertion: It is that the given type |
| // has no subtypes whatever. It is most useful for |
| // optimizing checks on reflected types or on array types. |
| // (Checks on types which are derived from real instances |
| // can be optimized more strongly than this, because we |
| // know that the checked type comes from a concrete type, |
| // and therefore we can disregard abstract types.) |
| Klass* Dependencies::check_leaf_type(Klass* ctxk) { |
| assert(must_be_in_vm(), "raw oops here"); |
| assert_locked_or_safepoint(Compile_lock); |
| InstanceKlass* ctx = InstanceKlass::cast(ctxk); |
| Klass* sub = ctx->subklass(); |
| if (sub != NULL) { |
| return sub; |
| } else if (ctx->nof_implementors() != 0) { |
| // if it is an interface, it must be unimplemented |
| // (if it is not an interface, nof_implementors is always zero) |
| Klass* impl = ctx->implementor(); |
| assert(impl != NULL, "must be set"); |
| return impl; |
| } else { |
| return NULL; |
| } |
| } |
| |
| // Test the assertion that conck is the only concrete subtype* of ctxk. |
| // The type conck itself is allowed to have have further concrete subtypes. |
| // This allows the compiler to narrow occurrences of ctxk by conck, |
| // when dealing with the types of actual instances. |
| Klass* Dependencies::check_abstract_with_unique_concrete_subtype(Klass* ctxk, |
| Klass* conck, |
| KlassDepChange* changes) { |
| ClassHierarchyWalker wf(conck); |
| return wf.find_witness_subtype(ctxk, changes); |
| } |
| |
| // If a non-concrete class has no concrete subtypes, it is not (yet) |
| // instantiatable. This can allow the compiler to make some paths go |
| // dead, if they are gated by a test of the type. |
| Klass* Dependencies::check_abstract_with_no_concrete_subtype(Klass* ctxk, |
| KlassDepChange* changes) { |
| // Find any concrete subtype, with no participants: |
| ClassHierarchyWalker wf; |
| return wf.find_witness_subtype(ctxk, changes); |
| } |
| |
| |
| // If a concrete class has no concrete subtypes, it can always be |
| // exactly typed. This allows the use of a cheaper type test. |
| Klass* Dependencies::check_concrete_with_no_concrete_subtype(Klass* ctxk, |
| KlassDepChange* changes) { |
| // Find any concrete subtype, with only the ctxk as participant: |
| ClassHierarchyWalker wf(ctxk); |
| return wf.find_witness_subtype(ctxk, changes); |
| } |
| |
| |
| // Find the unique concrete proper subtype of ctxk, or NULL if there |
| // is more than one concrete proper subtype. If there are no concrete |
| // proper subtypes, return ctxk itself, whether it is concrete or not. |
| // The returned subtype is allowed to have have further concrete subtypes. |
| // That is, return CC1 for CX > CC1 > CC2, but NULL for CX > { CC1, CC2 }. |
| Klass* Dependencies::find_unique_concrete_subtype(Klass* ctxk) { |
| ClassHierarchyWalker wf(ctxk); // Ignore ctxk when walking. |
| wf.record_witnesses(1); // Record one other witness when walking. |
| Klass* wit = wf.find_witness_subtype(ctxk); |
| if (wit != NULL) return NULL; // Too many witnesses. |
| Klass* conck = wf.participant(0); |
| if (conck == NULL) { |
| #ifndef PRODUCT |
| // Make sure the dependency mechanism will pass this discovery: |
| if (VerifyDependencies) { |
| // Turn off dependency tracing while actually testing deps. |
| FlagSetting fs(TraceDependencies, false); |
| if (!Dependencies::is_concrete_klass(ctxk)) { |
| guarantee(NULL == |
| (void *)check_abstract_with_no_concrete_subtype(ctxk), |
| "verify dep."); |
| } else { |
| guarantee(NULL == |
| (void *)check_concrete_with_no_concrete_subtype(ctxk), |
| "verify dep."); |
| } |
| } |
| #endif //PRODUCT |
| return ctxk; // Return ctxk as a flag for "no subtypes". |
| } else { |
| #ifndef PRODUCT |
| // Make sure the dependency mechanism will pass this discovery: |
| if (VerifyDependencies) { |
| // Turn off dependency tracing while actually testing deps. |
| FlagSetting fs(TraceDependencies, false); |
| if (!Dependencies::is_concrete_klass(ctxk)) { |
| guarantee(NULL == (void *) |
| check_abstract_with_unique_concrete_subtype(ctxk, conck), |
| "verify dep."); |
| } |
| } |
| #endif //PRODUCT |
| return conck; |
| } |
| } |
| |
| // Test the assertion that the k[12] are the only concrete subtypes of ctxk, |
| // except possibly for further subtypes of k[12] themselves. |
| // The context type must be abstract. The types k1 and k2 are themselves |
| // allowed to have further concrete subtypes. |
| Klass* Dependencies::check_abstract_with_exclusive_concrete_subtypes( |
| Klass* ctxk, |
| Klass* k1, |
| Klass* k2, |
| KlassDepChange* changes) { |
| ClassHierarchyWalker wf; |
| wf.add_participant(k1); |
| wf.add_participant(k2); |
| return wf.find_witness_subtype(ctxk, changes); |
| } |
| |
| // Search ctxk for concrete implementations. If there are klen or fewer, |
| // pack them into the given array and return the number. |
| // Otherwise, return -1, meaning the given array would overflow. |
| // (Note that a return of 0 means there are exactly no concrete subtypes.) |
| // In this search, if ctxk is concrete, it will be reported alone. |
| // For any type CC reported, no proper subtypes of CC will be reported. |
| int Dependencies::find_exclusive_concrete_subtypes(Klass* ctxk, |
| int klen, |
| Klass* karray[]) { |
| ClassHierarchyWalker wf; |
| wf.record_witnesses(klen); |
| Klass* wit = wf.find_witness_subtype(ctxk); |
| if (wit != NULL) return -1; // Too many witnesses. |
| int num = wf.num_participants(); |
| assert(num <= klen, "oob"); |
| // Pack the result array with the good news. |
| for (int i = 0; i < num; i++) |
| karray[i] = wf.participant(i); |
| #ifndef PRODUCT |
| // Make sure the dependency mechanism will pass this discovery: |
| if (VerifyDependencies) { |
| // Turn off dependency tracing while actually testing deps. |
| FlagSetting fs(TraceDependencies, false); |
| switch (Dependencies::is_concrete_klass(ctxk)? -1: num) { |
| case -1: // ctxk was itself concrete |
| guarantee(num == 1 && karray[0] == ctxk, "verify dep."); |
| break; |
| case 0: |
| guarantee(NULL == (void *)check_abstract_with_no_concrete_subtype(ctxk), |
| "verify dep."); |
| break; |
| case 1: |
| guarantee(NULL == (void *) |
| check_abstract_with_unique_concrete_subtype(ctxk, karray[0]), |
| "verify dep."); |
| break; |
| case 2: |
| guarantee(NULL == (void *) |
| check_abstract_with_exclusive_concrete_subtypes(ctxk, |
| karray[0], |
| karray[1]), |
| "verify dep."); |
| break; |
| default: |
| ShouldNotReachHere(); // klen > 2 yet supported |
| } |
| } |
| #endif //PRODUCT |
| return num; |
| } |
| |
| // If a class (or interface) has a unique concrete method uniqm, return NULL. |
| // Otherwise, return a class that contains an interfering method. |
| Klass* Dependencies::check_unique_concrete_method(Klass* ctxk, Method* uniqm, |
| KlassDepChange* changes) { |
| // Here is a missing optimization: If uniqm->is_final(), |
| // we don't really need to search beneath it for overrides. |
| // This is probably not important, since we don't use dependencies |
| // to track final methods. (They can't be "definalized".) |
| ClassHierarchyWalker wf(uniqm->method_holder(), uniqm); |
| return wf.find_witness_definer(ctxk, changes); |
| } |
| |
| // Find the set of all non-abstract methods under ctxk that match m. |
| // (The method m must be defined or inherited in ctxk.) |
| // Include m itself in the set, unless it is abstract. |
| // If this set has exactly one element, return that element. |
| Method* Dependencies::find_unique_concrete_method(Klass* ctxk, Method* m) { |
| ClassHierarchyWalker wf(m); |
| assert(wf.check_method_context(ctxk, m), "proper context"); |
| wf.record_witnesses(1); |
| Klass* wit = wf.find_witness_definer(ctxk); |
| if (wit != NULL) return NULL; // Too many witnesses. |
| Method* fm = wf.found_method(0); // Will be NULL if num_parts == 0. |
| if (Dependencies::is_concrete_method(m)) { |
| if (fm == NULL) { |
| // It turns out that m was always the only implementation. |
| fm = m; |
| } else if (fm != m) { |
| // Two conflicting implementations after all. |
| // (This can happen if m is inherited into ctxk and fm overrides it.) |
| return NULL; |
| } |
| } |
| #ifndef PRODUCT |
| // Make sure the dependency mechanism will pass this discovery: |
| if (VerifyDependencies && fm != NULL) { |
| guarantee(NULL == (void *)check_unique_concrete_method(ctxk, fm), |
| "verify dep."); |
| } |
| #endif //PRODUCT |
| return fm; |
| } |
| |
| Klass* Dependencies::check_exclusive_concrete_methods(Klass* ctxk, |
| Method* m1, |
| Method* m2, |
| KlassDepChange* changes) { |
| ClassHierarchyWalker wf(m1); |
| wf.add_participant(m1->method_holder()); |
| wf.add_participant(m2->method_holder()); |
| return wf.find_witness_definer(ctxk, changes); |
| } |
| |
| // Find the set of all non-abstract methods under ctxk that match m[0]. |
| // (The method m[0] must be defined or inherited in ctxk.) |
| // Include m itself in the set, unless it is abstract. |
| // Fill the given array m[0..(mlen-1)] with this set, and return the length. |
| // (The length may be zero if no concrete methods are found anywhere.) |
| // If there are too many concrete methods to fit in marray, return -1. |
| int Dependencies::find_exclusive_concrete_methods(Klass* ctxk, |
| int mlen, |
| Method* marray[]) { |
| Method* m0 = marray[0]; |
| ClassHierarchyWalker wf(m0); |
| assert(wf.check_method_context(ctxk, m0), "proper context"); |
| wf.record_witnesses(mlen); |
| bool participants_hide_witnesses = true; |
| Klass* wit = wf.find_witness_definer(ctxk); |
| if (wit != NULL) return -1; // Too many witnesses. |
| int num = wf.num_participants(); |
| assert(num <= mlen, "oob"); |
| // Keep track of whether m is also part of the result set. |
| int mfill = 0; |
| assert(marray[mfill] == m0, "sanity"); |
| if (Dependencies::is_concrete_method(m0)) |
| mfill++; // keep m0 as marray[0], the first result |
| for (int i = 0; i < num; i++) { |
| Method* fm = wf.found_method(i); |
| if (fm == m0) continue; // Already put this guy in the list. |
| if (mfill == mlen) { |
| return -1; // Oops. Too many methods after all! |
| } |
| marray[mfill++] = fm; |
| } |
| #ifndef PRODUCT |
| // Make sure the dependency mechanism will pass this discovery: |
| if (VerifyDependencies) { |
| // Turn off dependency tracing while actually testing deps. |
| FlagSetting fs(TraceDependencies, false); |
| switch (mfill) { |
| case 1: |
| guarantee(NULL == (void *)check_unique_concrete_method(ctxk, marray[0]), |
| "verify dep."); |
| break; |
| case 2: |
| guarantee(NULL == (void *) |
| check_exclusive_concrete_methods(ctxk, marray[0], marray[1]), |
| "verify dep."); |
| break; |
| default: |
| ShouldNotReachHere(); // mlen > 2 yet supported |
| } |
| } |
| #endif //PRODUCT |
| return mfill; |
| } |
| |
| |
| Klass* Dependencies::check_has_no_finalizable_subclasses(Klass* ctxk, KlassDepChange* changes) { |
| Klass* search_at = ctxk; |
| if (changes != NULL) |
| search_at = changes->new_type(); // just look at the new bit |
| return find_finalizable_subclass(search_at); |
| } |
| |
| |
| Klass* Dependencies::check_call_site_target_value(oop call_site, oop method_handle, CallSiteDepChange* changes) { |
| assert(call_site ->is_a(SystemDictionary::CallSite_klass()), "sanity"); |
| assert(method_handle->is_a(SystemDictionary::MethodHandle_klass()), "sanity"); |
| if (changes == NULL) { |
| // Validate all CallSites |
| if (java_lang_invoke_CallSite::target(call_site) != method_handle) |
| return call_site->klass(); // assertion failed |
| } else { |
| // Validate the given CallSite |
| if (call_site == changes->call_site() && java_lang_invoke_CallSite::target(call_site) != changes->method_handle()) { |
| assert(method_handle != changes->method_handle(), "must be"); |
| return call_site->klass(); // assertion failed |
| } |
| } |
| return NULL; // assertion still valid |
| } |
| |
| |
| void Dependencies::DepStream::trace_and_log_witness(Klass* witness) { |
| if (witness != NULL) { |
| if (TraceDependencies) { |
| print_dependency(witness, /*verbose=*/ true); |
| } |
| // The following is a no-op unless logging is enabled: |
| log_dependency(witness); |
| } |
| } |
| |
| |
| Klass* Dependencies::DepStream::check_klass_dependency(KlassDepChange* changes) { |
| assert_locked_or_safepoint(Compile_lock); |
| Dependencies::check_valid_dependency_type(type()); |
| |
| Klass* witness = NULL; |
| switch (type()) { |
| case evol_method: |
| witness = check_evol_method(method_argument(0)); |
| break; |
| case leaf_type: |
| witness = check_leaf_type(context_type()); |
| break; |
| case abstract_with_unique_concrete_subtype: |
| witness = check_abstract_with_unique_concrete_subtype(context_type(), type_argument(1), changes); |
| break; |
| case abstract_with_no_concrete_subtype: |
| witness = check_abstract_with_no_concrete_subtype(context_type(), changes); |
| break; |
| case concrete_with_no_concrete_subtype: |
| witness = check_concrete_with_no_concrete_subtype(context_type(), changes); |
| break; |
| case unique_concrete_method: |
| witness = check_unique_concrete_method(context_type(), method_argument(1), changes); |
| break; |
| case abstract_with_exclusive_concrete_subtypes_2: |
| witness = check_abstract_with_exclusive_concrete_subtypes(context_type(), type_argument(1), type_argument(2), changes); |
| break; |
| case exclusive_concrete_methods_2: |
| witness = check_exclusive_concrete_methods(context_type(), method_argument(1), method_argument(2), changes); |
| break; |
| case no_finalizable_subclasses: |
| witness = check_has_no_finalizable_subclasses(context_type(), changes); |
| break; |
| default: |
| witness = NULL; |
| break; |
| } |
| trace_and_log_witness(witness); |
| return witness; |
| } |
| |
| |
| Klass* Dependencies::DepStream::check_call_site_dependency(CallSiteDepChange* changes) { |
| assert_locked_or_safepoint(Compile_lock); |
| Dependencies::check_valid_dependency_type(type()); |
| |
| Klass* witness = NULL; |
| switch (type()) { |
| case call_site_target_value: |
| witness = check_call_site_target_value(argument_oop(0), argument_oop(1), changes); |
| break; |
| default: |
| witness = NULL; |
| break; |
| } |
| trace_and_log_witness(witness); |
| return witness; |
| } |
| |
| |
| Klass* Dependencies::DepStream::spot_check_dependency_at(DepChange& changes) { |
| // Handle klass dependency |
| if (changes.is_klass_change() && changes.as_klass_change()->involves_context(context_type())) |
| return check_klass_dependency(changes.as_klass_change()); |
| |
| // Handle CallSite dependency |
| if (changes.is_call_site_change()) |
| return check_call_site_dependency(changes.as_call_site_change()); |
| |
| // irrelevant dependency; skip it |
| return NULL; |
| } |
| |
| |
| void DepChange::print() { |
| int nsup = 0, nint = 0; |
| for (ContextStream str(*this); str.next(); ) { |
| Klass* k = str.klass(); |
| switch (str.change_type()) { |
| case Change_new_type: |
| tty->print_cr(" dependee = %s", InstanceKlass::cast(k)->external_name()); |
| break; |
| case Change_new_sub: |
| if (!WizardMode) { |
| ++nsup; |
| } else { |
| tty->print_cr(" context super = %s", InstanceKlass::cast(k)->external_name()); |
| } |
| break; |
| case Change_new_impl: |
| if (!WizardMode) { |
| ++nint; |
| } else { |
| tty->print_cr(" context interface = %s", InstanceKlass::cast(k)->external_name()); |
| } |
| break; |
| } |
| } |
| if (nsup + nint != 0) { |
| tty->print_cr(" context supers = %d, interfaces = %d", nsup, nint); |
| } |
| } |
| |
| void DepChange::ContextStream::start() { |
| Klass* new_type = _changes.is_klass_change() ? _changes.as_klass_change()->new_type() : (Klass*) NULL; |
| _change_type = (new_type == NULL ? NO_CHANGE : Start_Klass); |
| _klass = new_type; |
| _ti_base = NULL; |
| _ti_index = 0; |
| _ti_limit = 0; |
| } |
| |
| bool DepChange::ContextStream::next() { |
| switch (_change_type) { |
| case Start_Klass: // initial state; _klass is the new type |
| _ti_base = InstanceKlass::cast(_klass)->transitive_interfaces(); |
| _ti_index = 0; |
| _change_type = Change_new_type; |
| return true; |
| case Change_new_type: |
| // fall through: |
| _change_type = Change_new_sub; |
| case Change_new_sub: |
| // 6598190: brackets workaround Sun Studio C++ compiler bug 6629277 |
| { |
| _klass = InstanceKlass::cast(_klass)->super(); |
| if (_klass != NULL) { |
| return true; |
| } |
| } |
| // else set up _ti_limit and fall through: |
| _ti_limit = (_ti_base == NULL) ? 0 : _ti_base->length(); |
| _change_type = Change_new_impl; |
| case Change_new_impl: |
| if (_ti_index < _ti_limit) { |
| _klass = _ti_base->at(_ti_index++); |
| return true; |
| } |
| // fall through: |
| _change_type = NO_CHANGE; // iterator is exhausted |
| case NO_CHANGE: |
| break; |
| default: |
| ShouldNotReachHere(); |
| } |
| return false; |
| } |
| |
| void KlassDepChange::initialize() { |
| // entire transaction must be under this lock: |
| assert_lock_strong(Compile_lock); |
| |
| // Mark all dependee and all its superclasses |
| // Mark transitive interfaces |
| for (ContextStream str(*this); str.next(); ) { |
| Klass* d = str.klass(); |
| assert(!InstanceKlass::cast(d)->is_marked_dependent(), "checking"); |
| InstanceKlass::cast(d)->set_is_marked_dependent(true); |
| } |
| } |
| |
| KlassDepChange::~KlassDepChange() { |
| // Unmark all dependee and all its superclasses |
| // Unmark transitive interfaces |
| for (ContextStream str(*this); str.next(); ) { |
| Klass* d = str.klass(); |
| InstanceKlass::cast(d)->set_is_marked_dependent(false); |
| } |
| } |
| |
| bool KlassDepChange::involves_context(Klass* k) { |
| if (k == NULL || !k->oop_is_instance()) { |
| return false; |
| } |
| InstanceKlass* ik = InstanceKlass::cast(k); |
| bool is_contained = ik->is_marked_dependent(); |
| assert(is_contained == new_type()->is_subtype_of(k), |
| "correct marking of potential context types"); |
| return is_contained; |
| } |
| |
| #ifndef PRODUCT |
| void Dependencies::print_statistics() { |
| if (deps_find_witness_print != 0) { |
| // Call one final time, to flush out the data. |
| deps_find_witness_print = -1; |
| count_find_witness_calls(); |
| } |
| } |
| #endif |