--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/classfile/stackMapTable.cpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,420 @@
+/*
+ * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "classfile/stackMapTable.hpp"
+#include "classfile/verifier.hpp"
+#include "memory/resourceArea.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/fieldType.hpp"
+#include "runtime/handles.inline.hpp"
+
+StackMapTable::StackMapTable(StackMapReader* reader, StackMapFrame* init_frame,
+ u2 max_locals, u2 max_stack,
+ char* code_data, int code_len, TRAPS) {
+ _code_length = code_len;
+ _frame_count = reader->get_frame_count();
+ if (_frame_count > 0) {
+ _frame_array = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD,
+ StackMapFrame*, _frame_count);
+ StackMapFrame* pre_frame = init_frame;
+ for (int32_t i = 0; i < _frame_count; i++) {
+ StackMapFrame* frame = reader->next(
+ pre_frame, i == 0, max_locals, max_stack,
+ CHECK_VERIFY(pre_frame->verifier()));
+ _frame_array[i] = frame;
+ int offset = frame->offset();
+ if (offset >= code_len || code_data[offset] == 0) {
+ frame->verifier()->verify_error(
+ ErrorContext::bad_stackmap(i, frame),
+ "StackMapTable error: bad offset");
+ return;
+ }
+ pre_frame = frame;
+ }
+ }
+ reader->check_end(CHECK);
+}
+
+// This method is only called by method in StackMapTable.
+int StackMapTable::get_index_from_offset(int32_t offset) const {
+ int i = 0;
+ for (; i < _frame_count; i++) {
+ if (_frame_array[i]->offset() == offset) {
+ return i;
+ }
+ }
+ return i; // frame with offset doesn't exist in the array
+}
+
+bool StackMapTable::match_stackmap(
+ StackMapFrame* frame, int32_t target,
+ bool match, bool update, ErrorContext* ctx, TRAPS) const {
+ int index = get_index_from_offset(target);
+ return match_stackmap(frame, target, index, match, update, ctx, THREAD);
+}
+
+// Match and/or update current_frame to the frame in stackmap table with
+// specified offset and frame index. Return true if the two frames match.
+//
+// The values of match and update are: _match__update
+//
+// checking a branch target: true false
+// checking an exception handler: true false
+// linear bytecode verification following an
+// unconditional branch: false true
+// linear bytecode verification not following an
+// unconditional branch: true true
+bool StackMapTable::match_stackmap(
+ StackMapFrame* frame, int32_t target, int32_t frame_index,
+ bool match, bool update, ErrorContext* ctx, TRAPS) const {
+ if (frame_index < 0 || frame_index >= _frame_count) {
+ *ctx = ErrorContext::missing_stackmap(frame->offset());
+ frame->verifier()->verify_error(
+ *ctx, "Expecting a stackmap frame at branch target %d", target);
+ return false;
+ }
+
+ StackMapFrame *stackmap_frame = _frame_array[frame_index];
+ bool result = true;
+ if (match) {
+ // Has direct control flow from last instruction, need to match the two
+ // frames.
+ result = frame->is_assignable_to(stackmap_frame,
+ ctx, CHECK_VERIFY_(frame->verifier(), result));
+ }
+ if (update) {
+ // Use the frame in stackmap table as current frame
+ int lsize = stackmap_frame->locals_size();
+ int ssize = stackmap_frame->stack_size();
+ if (frame->locals_size() > lsize || frame->stack_size() > ssize) {
+ // Make sure unused type array items are all _bogus_type.
+ frame->reset();
+ }
+ frame->set_locals_size(lsize);
+ frame->copy_locals(stackmap_frame);
+ frame->set_stack_size(ssize);
+ frame->copy_stack(stackmap_frame);
+ frame->set_flags(stackmap_frame->flags());
+ }
+ return result;
+}
+
+void StackMapTable::check_jump_target(
+ StackMapFrame* frame, int32_t target, TRAPS) const {
+ ErrorContext ctx;
+ bool match = match_stackmap(
+ frame, target, true, false, &ctx, CHECK_VERIFY(frame->verifier()));
+ if (!match || (target < 0 || target >= _code_length)) {
+ frame->verifier()->verify_error(ctx,
+ "Inconsistent stackmap frames at branch target %d", target);
+ }
+}
+
+void StackMapTable::print_on(outputStream* str) const {
+ str->indent().print_cr("StackMapTable: frame_count = %d", _frame_count);
+ str->indent().print_cr("table = { ");
+ {
+ streamIndentor si(str);
+ for (int32_t i = 0; i < _frame_count; ++i) {
+ _frame_array[i]->print_on(str);
+ }
+ }
+ str->print_cr(" }");
+}
+
+int32_t StackMapReader::chop(
+ VerificationType* locals, int32_t length, int32_t chops) {
+ if (locals == NULL) return -1;
+ int32_t pos = length - 1;
+ for (int32_t i=0; i<chops; i++) {
+ if (locals[pos].is_category2_2nd()) {
+ pos -= 2;
+ } else {
+ pos --;
+ }
+ if (pos<0 && i<(chops-1)) return -1;
+ }
+ return pos+1;
+}
+
+VerificationType StackMapReader::parse_verification_type(u1* flags, TRAPS) {
+ u1 tag = _stream->get_u1(THREAD);
+ if (tag < (u1)ITEM_UninitializedThis) {
+ return VerificationType::from_tag(tag);
+ }
+ if (tag == ITEM_Object) {
+ u2 class_index = _stream->get_u2(THREAD);
+ int nconstants = _cp->length();
+ if ((class_index <= 0 || class_index >= nconstants) ||
+ (!_cp->tag_at(class_index).is_klass() &&
+ !_cp->tag_at(class_index).is_unresolved_klass())) {
+ _stream->stackmap_format_error("bad class index", THREAD);
+ return VerificationType::bogus_type();
+ }
+ return VerificationType::reference_type(_cp->klass_name_at(class_index));
+ }
+ if (tag == ITEM_UninitializedThis) {
+ if (flags != NULL) {
+ *flags |= FLAG_THIS_UNINIT;
+ }
+ return VerificationType::uninitialized_this_type();
+ }
+ if (tag == ITEM_Uninitialized) {
+ u2 offset = _stream->get_u2(THREAD);
+ if (offset >= _code_length ||
+ _code_data[offset] != ClassVerifier::NEW_OFFSET) {
+ _verifier->class_format_error(
+ "StackMapTable format error: bad offset for Uninitialized");
+ return VerificationType::bogus_type();
+ }
+ return VerificationType::uninitialized_type(offset);
+ }
+ _stream->stackmap_format_error("bad verification type", THREAD);
+ return VerificationType::bogus_type();
+}
+
+StackMapFrame* StackMapReader::next(
+ StackMapFrame* pre_frame, bool first, u2 max_locals, u2 max_stack, TRAPS) {
+ StackMapFrame* frame;
+ int offset;
+ VerificationType* locals = NULL;
+ u1 frame_type = _stream->get_u1(THREAD);
+ if (frame_type < 64) {
+ // same_frame
+ if (first) {
+ offset = frame_type;
+ // Can't share the locals array since that is updated by the verifier.
+ if (pre_frame->locals_size() > 0) {
+ locals = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, pre_frame->locals_size());
+ }
+ } else {
+ offset = pre_frame->offset() + frame_type + 1;
+ locals = pre_frame->locals();
+ }
+ frame = new StackMapFrame(
+ offset, pre_frame->flags(), pre_frame->locals_size(), 0,
+ max_locals, max_stack, locals, NULL, _verifier);
+ if (first && locals != NULL) {
+ frame->copy_locals(pre_frame);
+ }
+ return frame;
+ }
+ if (frame_type < 128) {
+ // same_locals_1_stack_item_frame
+ if (first) {
+ offset = frame_type - 64;
+ // Can't share the locals array since that is updated by the verifier.
+ if (pre_frame->locals_size() > 0) {
+ locals = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, pre_frame->locals_size());
+ }
+ } else {
+ offset = pre_frame->offset() + frame_type - 63;
+ locals = pre_frame->locals();
+ }
+ VerificationType* stack = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, 2);
+ u2 stack_size = 1;
+ stack[0] = parse_verification_type(NULL, CHECK_VERIFY_(_verifier, NULL));
+ if (stack[0].is_category2()) {
+ stack[1] = stack[0].to_category2_2nd();
+ stack_size = 2;
+ }
+ check_verification_type_array_size(
+ stack_size, max_stack, CHECK_VERIFY_(_verifier, NULL));
+ frame = new StackMapFrame(
+ offset, pre_frame->flags(), pre_frame->locals_size(), stack_size,
+ max_locals, max_stack, locals, stack, _verifier);
+ if (first && locals != NULL) {
+ frame->copy_locals(pre_frame);
+ }
+ return frame;
+ }
+
+ u2 offset_delta = _stream->get_u2(THREAD);
+
+ if (frame_type < SAME_LOCALS_1_STACK_ITEM_EXTENDED) {
+ // reserved frame types
+ _stream->stackmap_format_error(
+ "reserved frame type", CHECK_VERIFY_(_verifier, NULL));
+ }
+
+ if (frame_type == SAME_LOCALS_1_STACK_ITEM_EXTENDED) {
+ // same_locals_1_stack_item_frame_extended
+ if (first) {
+ offset = offset_delta;
+ // Can't share the locals array since that is updated by the verifier.
+ if (pre_frame->locals_size() > 0) {
+ locals = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, pre_frame->locals_size());
+ }
+ } else {
+ offset = pre_frame->offset() + offset_delta + 1;
+ locals = pre_frame->locals();
+ }
+ VerificationType* stack = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, 2);
+ u2 stack_size = 1;
+ stack[0] = parse_verification_type(NULL, CHECK_VERIFY_(_verifier, NULL));
+ if (stack[0].is_category2()) {
+ stack[1] = stack[0].to_category2_2nd();
+ stack_size = 2;
+ }
+ check_verification_type_array_size(
+ stack_size, max_stack, CHECK_VERIFY_(_verifier, NULL));
+ frame = new StackMapFrame(
+ offset, pre_frame->flags(), pre_frame->locals_size(), stack_size,
+ max_locals, max_stack, locals, stack, _verifier);
+ if (first && locals != NULL) {
+ frame->copy_locals(pre_frame);
+ }
+ return frame;
+ }
+
+ if (frame_type <= SAME_EXTENDED) {
+ // chop_frame or same_frame_extended
+ locals = pre_frame->locals();
+ int length = pre_frame->locals_size();
+ int chops = SAME_EXTENDED - frame_type;
+ int new_length = length;
+ u1 flags = pre_frame->flags();
+ if (chops != 0) {
+ new_length = chop(locals, length, chops);
+ check_verification_type_array_size(
+ new_length, max_locals, CHECK_VERIFY_(_verifier, NULL));
+ // Recompute flags since uninitializedThis could have been chopped.
+ flags = 0;
+ for (int i=0; i<new_length; i++) {
+ if (locals[i].is_uninitialized_this()) {
+ flags |= FLAG_THIS_UNINIT;
+ break;
+ }
+ }
+ }
+ if (first) {
+ offset = offset_delta;
+ // Can't share the locals array since that is updated by the verifier.
+ if (new_length > 0) {
+ locals = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, new_length);
+ } else {
+ locals = NULL;
+ }
+ } else {
+ offset = pre_frame->offset() + offset_delta + 1;
+ }
+ frame = new StackMapFrame(
+ offset, flags, new_length, 0, max_locals, max_stack,
+ locals, NULL, _verifier);
+ if (first && locals != NULL) {
+ frame->copy_locals(pre_frame);
+ }
+ return frame;
+ } else if (frame_type < SAME_EXTENDED + 4) {
+ // append_frame
+ int appends = frame_type - SAME_EXTENDED;
+ int real_length = pre_frame->locals_size();
+ int new_length = real_length + appends*2;
+ locals = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, VerificationType, new_length);
+ VerificationType* pre_locals = pre_frame->locals();
+ int i;
+ for (i=0; i<pre_frame->locals_size(); i++) {
+ locals[i] = pre_locals[i];
+ }
+ u1 flags = pre_frame->flags();
+ for (i=0; i<appends; i++) {
+ locals[real_length] = parse_verification_type(&flags, THREAD);
+ if (locals[real_length].is_category2()) {
+ locals[real_length + 1] = locals[real_length].to_category2_2nd();
+ ++real_length;
+ }
+ ++real_length;
+ }
+ check_verification_type_array_size(
+ real_length, max_locals, CHECK_VERIFY_(_verifier, NULL));
+ if (first) {
+ offset = offset_delta;
+ } else {
+ offset = pre_frame->offset() + offset_delta + 1;
+ }
+ frame = new StackMapFrame(
+ offset, flags, real_length, 0, max_locals,
+ max_stack, locals, NULL, _verifier);
+ return frame;
+ }
+ if (frame_type == FULL) {
+ // full_frame
+ u1 flags = 0;
+ u2 locals_size = _stream->get_u2(THREAD);
+ int real_locals_size = 0;
+ if (locals_size > 0) {
+ locals = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, locals_size*2);
+ }
+ int i;
+ for (i=0; i<locals_size; i++) {
+ locals[real_locals_size] = parse_verification_type(&flags, THREAD);
+ if (locals[real_locals_size].is_category2()) {
+ locals[real_locals_size + 1] =
+ locals[real_locals_size].to_category2_2nd();
+ ++real_locals_size;
+ }
+ ++real_locals_size;
+ }
+ check_verification_type_array_size(
+ real_locals_size, max_locals, CHECK_VERIFY_(_verifier, NULL));
+ u2 stack_size = _stream->get_u2(THREAD);
+ int real_stack_size = 0;
+ VerificationType* stack = NULL;
+ if (stack_size > 0) {
+ stack = NEW_RESOURCE_ARRAY_IN_THREAD(
+ THREAD, VerificationType, stack_size*2);
+ }
+ for (i=0; i<stack_size; i++) {
+ stack[real_stack_size] = parse_verification_type(NULL, THREAD);
+ if (stack[real_stack_size].is_category2()) {
+ stack[real_stack_size + 1] = stack[real_stack_size].to_category2_2nd();
+ ++real_stack_size;
+ }
+ ++real_stack_size;
+ }
+ check_verification_type_array_size(
+ real_stack_size, max_stack, CHECK_VERIFY_(_verifier, NULL));
+ if (first) {
+ offset = offset_delta;
+ } else {
+ offset = pre_frame->offset() + offset_delta + 1;
+ }
+ frame = new StackMapFrame(
+ offset, flags, real_locals_size, real_stack_size,
+ max_locals, max_stack, locals, stack, _verifier);
+ return frame;
+ }
+
+ _stream->stackmap_format_error(
+ "reserved frame type", CHECK_VERIFY_(pre_frame->verifier(), NULL));
+ return NULL;
+}