1 /*
2 * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/stackMapFrame.hpp"
27 #include "classfile/verifier.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "oops/oop.inline.hpp"
31 #include "oops/symbol.hpp"
32 #include "runtime/handles.inline.hpp"
33 #include "utilities/globalDefinitions.hpp"
34
35 StackMapFrame::StackMapFrame(u2 max_locals, u2 max_stack, ClassVerifier* v) :
36 _offset(0), _locals_size(0), _stack_size(0),
37 _stack_mark(0), _max_locals(max_locals),
38 _max_stack(max_stack), _flags(0), _verifier(v) {
39 Thread* thr = v->thread();
40 _locals = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, max_locals);
41 _stack = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, max_stack);
42 int32_t i;
43 for(i = 0; i < max_locals; i++) {
44 _locals[i] = VerificationType::bogus_type();
45 }
46 for(i = 0; i < max_stack; i++) {
47 _stack[i] = VerificationType::bogus_type();
48 }
49 }
50
51 StackMapFrame* StackMapFrame::frame_in_exception_handler(u1 flags) {
52 Thread* thr = _verifier->thread();
53 VerificationType* stack = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, 1);
54 StackMapFrame* frame = new StackMapFrame(_offset, flags, _locals_size, 0, _max_locals, _max_stack, _locals, stack, _verifier);
55 return frame;
56 }
57
58 void StackMapFrame::initialize_object(
59 VerificationType old_object, VerificationType new_object) {
60 int32_t i;
61 for (i = 0; i < _max_locals; i++) {
62 if (_locals[i].equals(old_object)) {
63 _locals[i] = new_object;
64 }
65 }
66 for (i = 0; i < _stack_size; i++) {
67 if (_stack[i].equals(old_object)) {
68 _stack[i] = new_object;
69 }
70 }
71 if (old_object == VerificationType::uninitialized_this_type()) {
72 // "this" has been initialized - reset flags
73 _flags = 0;
74 }
75 }
76
77 VerificationType StackMapFrame::set_locals_from_arg(
78 const methodHandle& m, VerificationType thisKlass) {
79 SignatureStream ss(m->signature());
80 int init_local_num = 0;
81 if (!m->is_static()) {
82 init_local_num++;
83 // add one extra argument for instance method
84 if (m->name() == vmSymbols::object_initializer_name() &&
85 thisKlass.name() != vmSymbols::java_lang_Object()) {
86 _locals[0] = VerificationType::uninitialized_this_type();
87 _flags |= FLAG_THIS_UNINIT;
88 } else {
89 _locals[0] = thisKlass;
90 }
91 }
92
93 // local num may be greater than size of parameters because long/double occupies two slots
94 while(!ss.at_return_type()) {
95 init_local_num += _verifier->change_sig_to_verificationType(
96 &ss, &_locals[init_local_num]);
97 ss.next();
98 }
99 _locals_size = init_local_num;
100
101 switch (ss.type()) {
102 case T_OBJECT:
103 case T_ARRAY:
104 {
105 Symbol* sig = ss.as_symbol();
106 if (!sig->is_permanent()) {
107 // Create another symbol to save as signature stream unreferences
108 // this symbol.
109 Symbol *sig_copy =
110 verifier()->create_temporary_symbol(sig);
111 assert(sig_copy == sig, "symbols don't match");
112 sig = sig_copy;
113 }
114 return VerificationType::reference_type(sig);
115 }
116 case T_INT: return VerificationType::integer_type();
117 case T_BYTE: return VerificationType::byte_type();
118 case T_CHAR: return VerificationType::char_type();
119 case T_SHORT: return VerificationType::short_type();
120 case T_BOOLEAN: return VerificationType::boolean_type();
121 case T_FLOAT: return VerificationType::float_type();
122 case T_DOUBLE: return VerificationType::double_type();
123 case T_LONG: return VerificationType::long_type();
124 case T_VOID: return VerificationType::bogus_type();
125 default:
126 ShouldNotReachHere();
127 }
128 return VerificationType::bogus_type();
129 }
130
131 void StackMapFrame::copy_locals(const StackMapFrame* src) {
132 int32_t len = src->locals_size() < _locals_size ?
133 src->locals_size() : _locals_size;
134 for (int32_t i = 0; i < len; i++) {
135 _locals[i] = src->locals()[i];
136 }
137 }
138
139 void StackMapFrame::copy_stack(const StackMapFrame* src) {
140 int32_t len = src->stack_size() < _stack_size ?
141 src->stack_size() : _stack_size;
142 for (int32_t i = 0; i < len; i++) {
143 _stack[i] = src->stack()[i];
144 }
145 }
146
147 // Returns the location of the first mismatch, or 'len' if there are no
148 // mismatches
149 int StackMapFrame::is_assignable_to(
150 VerificationType* from, VerificationType* to, int32_t len, TRAPS) const {
151 int32_t i = 0;
152 for (i = 0; i < len; i++) {
153 if (!to[i].is_assignable_from(from[i], verifier(), false, THREAD)) {
154 break;
155 }
156 }
157 return i;
158 }
159
160 bool StackMapFrame::is_assignable_to(
161 const StackMapFrame* target, ErrorContext* ctx, TRAPS) const {
162 if (_max_locals != target->max_locals()) {
163 *ctx = ErrorContext::locals_size_mismatch(
164 _offset, (StackMapFrame*)this, (StackMapFrame*)target);
165 return false;
166 }
167 if (_stack_size != target->stack_size()) {
168 *ctx = ErrorContext::stack_size_mismatch(
169 _offset, (StackMapFrame*)this, (StackMapFrame*)target);
170 return false;
171 }
172 // Only need to compare type elements up to target->locals() or target->stack().
173 // The remaining type elements in this state can be ignored because they are
174 // assignable to bogus type.
175 int mismatch_loc;
176 mismatch_loc = is_assignable_to(
177 _locals, target->locals(), target->locals_size(), THREAD);
178 if (mismatch_loc != target->locals_size()) {
179 *ctx = ErrorContext::bad_type(target->offset(),
180 TypeOrigin::local(mismatch_loc, (StackMapFrame*)this),
181 TypeOrigin::sm_local(mismatch_loc, (StackMapFrame*)target));
182 return false;
183 }
184 mismatch_loc = is_assignable_to(_stack, target->stack(), _stack_size, THREAD);
185 if (mismatch_loc != _stack_size) {
186 *ctx = ErrorContext::bad_type(target->offset(),
187 TypeOrigin::stack(mismatch_loc, (StackMapFrame*)this),
188 TypeOrigin::sm_stack(mismatch_loc, (StackMapFrame*)target));
189 return false;
190 }
191
192 if ((_flags | target->flags()) == target->flags()) {
193 return true;
194 } else {
195 *ctx = ErrorContext::bad_flags(target->offset(),
196 (StackMapFrame*)this, (StackMapFrame*)target);
197 return false;
198 }
199 }
200
201 VerificationType StackMapFrame::pop_stack_ex(VerificationType type, TRAPS) {
202 if (_stack_size <= 0) {
203 verifier()->verify_error(
204 ErrorContext::stack_underflow(_offset, this),
205 "Operand stack underflow");
206 return VerificationType::bogus_type();
207 }
208 VerificationType top = _stack[--_stack_size];
209 bool subtype = type.is_assignable_from(
210 top, verifier(), false, CHECK_(VerificationType::bogus_type()));
211 if (!subtype) {
212 verifier()->verify_error(
213 ErrorContext::bad_type(_offset, stack_top_ctx(),
214 TypeOrigin::implicit(type)),
215 "Bad type on operand stack");
216 return VerificationType::bogus_type();
217 }
218 return top;
219 }
220
221 VerificationType StackMapFrame::get_local(
222 int32_t index, VerificationType type, TRAPS) {
223 if (index >= _max_locals) {
224 verifier()->verify_error(
225 ErrorContext::bad_local_index(_offset, index),
226 "Local variable table overflow");
227 return VerificationType::bogus_type();
228 }
229 bool subtype = type.is_assignable_from(_locals[index],
230 verifier(), false, CHECK_(VerificationType::bogus_type()));
231 if (!subtype) {
232 verifier()->verify_error(
233 ErrorContext::bad_type(_offset,
234 TypeOrigin::local(index, this),
235 TypeOrigin::implicit(type)),
236 "Bad local variable type");
237 return VerificationType::bogus_type();
238 }
239 if(index >= _locals_size) { _locals_size = index + 1; }
240 return _locals[index];
241 }
242
243 void StackMapFrame::get_local_2(
244 int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
245 assert(type1.is_long() || type1.is_double(), "must be long/double");
246 assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
247 if (index >= _locals_size - 1) {
248 verifier()->verify_error(
249 ErrorContext::bad_local_index(_offset, index),
250 "get long/double overflows locals");
251 return;
252 }
253 bool subtype = type1.is_assignable_from(_locals[index], verifier(), false, CHECK);
254 if (!subtype) {
255 verifier()->verify_error(
256 ErrorContext::bad_type(_offset,
257 TypeOrigin::local(index, this), TypeOrigin::implicit(type1)),
258 "Bad local variable type");
259 } else {
260 subtype = type2.is_assignable_from(_locals[index + 1], verifier(), false, CHECK);
261 if (!subtype) {
262 /* Unreachable? All local store routines convert a split long or double
263 * into a TOP during the store. So we should never end up seeing an
264 * orphaned half. */
265 verifier()->verify_error(
266 ErrorContext::bad_type(_offset,
267 TypeOrigin::local(index + 1, this), TypeOrigin::implicit(type2)),
268 "Bad local variable type");
269 }
270 }
271 }
272
273 void StackMapFrame::set_local(int32_t index, VerificationType type, TRAPS) {
274 assert(!type.is_check(), "Must be a real type");
275 if (index >= _max_locals) {
276 verifier()->verify_error(
277 ErrorContext::bad_local_index(_offset, index),
278 "Local variable table overflow");
279 return;
280 }
281 // If type at index is double or long, set the next location to be unusable
282 if (_locals[index].is_double() || _locals[index].is_long()) {
283 assert((index + 1) < _locals_size, "Local variable table overflow");
284 _locals[index + 1] = VerificationType::bogus_type();
285 }
286 // If type at index is double_2 or long_2, set the previous location to be unusable
287 if (_locals[index].is_double2() || _locals[index].is_long2()) {
288 assert(index >= 1, "Local variable table underflow");
289 _locals[index - 1] = VerificationType::bogus_type();
290 }
291 _locals[index] = type;
292 if (index >= _locals_size) {
293 #ifdef ASSERT
294 for (int i=_locals_size; i<index; i++) {
295 assert(_locals[i] == VerificationType::bogus_type(),
296 "holes must be bogus type");
297 }
298 #endif
299 _locals_size = index + 1;
300 }
301 }
302
303 void StackMapFrame::set_local_2(
304 int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
305 assert(type1.is_long() || type1.is_double(), "must be long/double");
306 assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
307 if (index >= _max_locals - 1) {
308 verifier()->verify_error(
309 ErrorContext::bad_local_index(_offset, index),
310 "Local variable table overflow");
311 return;
312 }
313 // If type at index+1 is double or long, set the next location to be unusable
314 if (_locals[index+1].is_double() || _locals[index+1].is_long()) {
315 assert((index + 2) < _locals_size, "Local variable table overflow");
316 _locals[index + 2] = VerificationType::bogus_type();
317 }
318 // If type at index is double_2 or long_2, set the previous location to be unusable
319 if (_locals[index].is_double2() || _locals[index].is_long2()) {
320 assert(index >= 1, "Local variable table underflow");
321 _locals[index - 1] = VerificationType::bogus_type();
322 }
323 _locals[index] = type1;
324 _locals[index+1] = type2;
325 if (index >= _locals_size - 1) {
326 #ifdef ASSERT
327 for (int i=_locals_size; i<index; i++) {
328 assert(_locals[i] == VerificationType::bogus_type(),
329 "holes must be bogus type");
330 }
331 #endif
332 _locals_size = index + 2;
333 }
334 }
335
336 TypeOrigin StackMapFrame::stack_top_ctx() {
337 return TypeOrigin::stack(_stack_size, this);
338 }
339
340 void StackMapFrame::print_on(outputStream* str) const {
341 str->indent().print_cr("bci: @%d", _offset);
342 str->indent().print_cr("flags: {%s }",
343 flag_this_uninit() ? " flagThisUninit" : "");
344 str->indent().print("locals: {");
345 for (int32_t i = 0; i < _locals_size; ++i) {
346 str->print(" ");
347 _locals[i].print_on(str);
348 if (i != _locals_size - 1) {
349 str->print(",");
350 }
351 }
352 str->print_cr(" }");
353 str->indent().print("stack: {");
354 for (int32_t j = 0; j < _stack_size; ++j) {
355 str->print(" ");
356 _stack[j].print_on(str);
357 if (j != _stack_size - 1) {
358 str->print(",");
359 }
360 }
361 str->print_cr(" }");
362 }