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->is_object_constructor() &&
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 case T_PRIMITIVE_OBJECT:
105 {
106 Symbol* sig = ss.as_symbol();
107 if (!sig->is_permanent()) {
108 // Create another symbol to save as signature stream unreferences
109 // this symbol.
110 Symbol *sig_copy =
111 verifier()->create_temporary_symbol(sig);
112 assert(sig_copy == sig, "symbols don't match");
113 sig = sig_copy;
114 }
115 if (ss.type() == T_PRIMITIVE_OBJECT) {
116 return VerificationType::inline_type(sig);
117 }
118 return VerificationType::reference_type(sig);
119 }
120 case T_INT: return VerificationType::integer_type();
121 case T_BYTE: return VerificationType::byte_type();
122 case T_CHAR: return VerificationType::char_type();
123 case T_SHORT: return VerificationType::short_type();
124 case T_BOOLEAN: return VerificationType::boolean_type();
125 case T_FLOAT: return VerificationType::float_type();
126 case T_DOUBLE: return VerificationType::double_type();
127 case T_LONG: return VerificationType::long_type();
128 case T_VOID: return VerificationType::bogus_type();
129 default:
130 ShouldNotReachHere();
131 }
132 return VerificationType::bogus_type();
133 }
134
135 void StackMapFrame::copy_locals(const StackMapFrame* src) {
136 int32_t len = src->locals_size() < _locals_size ?
137 src->locals_size() : _locals_size;
138 for (int32_t i = 0; i < len; i++) {
139 _locals[i] = src->locals()[i];
140 }
141 }
142
143 void StackMapFrame::copy_stack(const StackMapFrame* src) {
144 int32_t len = src->stack_size() < _stack_size ?
145 src->stack_size() : _stack_size;
146 for (int32_t i = 0; i < len; i++) {
147 _stack[i] = src->stack()[i];
148 }
149 }
150
151 // Returns the location of the first mismatch, or 'len' if there are no
152 // mismatches
153 int StackMapFrame::is_assignable_to(
154 VerificationType* from, VerificationType* to, int32_t len, TRAPS) const {
155 int32_t i = 0;
156 for (i = 0; i < len; i++) {
157 if (!to[i].is_assignable_from(from[i], verifier(), false, THREAD)) {
158 break;
159 }
160 }
161 return i;
162 }
163
164 bool StackMapFrame::is_assignable_to(
165 const StackMapFrame* target, ErrorContext* ctx, TRAPS) const {
166 if (_max_locals != target->max_locals()) {
167 *ctx = ErrorContext::locals_size_mismatch(
168 _offset, (StackMapFrame*)this, (StackMapFrame*)target);
169 return false;
170 }
171 if (_stack_size != target->stack_size()) {
172 *ctx = ErrorContext::stack_size_mismatch(
173 _offset, (StackMapFrame*)this, (StackMapFrame*)target);
174 return false;
175 }
176 // Only need to compare type elements up to target->locals() or target->stack().
177 // The remaining type elements in this state can be ignored because they are
178 // assignable to bogus type.
179 int mismatch_loc;
180 mismatch_loc = is_assignable_to(
181 _locals, target->locals(), target->locals_size(), THREAD);
182 if (mismatch_loc != target->locals_size()) {
183 *ctx = ErrorContext::bad_type(target->offset(),
184 TypeOrigin::local(mismatch_loc, (StackMapFrame*)this),
185 TypeOrigin::sm_local(mismatch_loc, (StackMapFrame*)target));
186 return false;
187 }
188 mismatch_loc = is_assignable_to(_stack, target->stack(), _stack_size, THREAD);
189 if (mismatch_loc != _stack_size) {
190 *ctx = ErrorContext::bad_type(target->offset(),
191 TypeOrigin::stack(mismatch_loc, (StackMapFrame*)this),
192 TypeOrigin::sm_stack(mismatch_loc, (StackMapFrame*)target));
193 return false;
194 }
195
196 if ((_flags | target->flags()) == target->flags()) {
197 return true;
198 } else {
199 *ctx = ErrorContext::bad_flags(target->offset(),
200 (StackMapFrame*)this, (StackMapFrame*)target);
201 return false;
202 }
203 }
204
205 VerificationType StackMapFrame::pop_stack_ex(VerificationType type, TRAPS) {
206 if (_stack_size <= 0) {
207 verifier()->verify_error(
208 ErrorContext::stack_underflow(_offset, this),
209 "Operand stack underflow");
210 return VerificationType::bogus_type();
211 }
212 VerificationType top = _stack[--_stack_size];
213 bool subtype = type.is_assignable_from(
214 top, verifier(), false, CHECK_(VerificationType::bogus_type()));
215 if (!subtype) {
216 verifier()->verify_error(
217 ErrorContext::bad_type(_offset, stack_top_ctx(),
218 TypeOrigin::implicit(type)),
219 "Bad type on operand stack");
220 return VerificationType::bogus_type();
221 }
222 return top;
223 }
224
225 VerificationType StackMapFrame::get_local(
226 int32_t index, VerificationType type, TRAPS) {
227 if (index >= _max_locals) {
228 verifier()->verify_error(
229 ErrorContext::bad_local_index(_offset, index),
230 "Local variable table overflow");
231 return VerificationType::bogus_type();
232 }
233 bool subtype = type.is_assignable_from(_locals[index],
234 verifier(), false, CHECK_(VerificationType::bogus_type()));
235 if (!subtype) {
236 verifier()->verify_error(
237 ErrorContext::bad_type(_offset,
238 TypeOrigin::local(index, this),
239 TypeOrigin::implicit(type)),
240 "Bad local variable type");
241 return VerificationType::bogus_type();
242 }
243 if(index >= _locals_size) { _locals_size = index + 1; }
244 return _locals[index];
245 }
246
247 void StackMapFrame::get_local_2(
248 int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
249 assert(type1.is_long() || type1.is_double(), "must be long/double");
250 assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
251 if (index >= _locals_size - 1) {
252 verifier()->verify_error(
253 ErrorContext::bad_local_index(_offset, index),
254 "get long/double overflows locals");
255 return;
256 }
257 bool subtype = type1.is_assignable_from(_locals[index], verifier(), false, CHECK);
258 if (!subtype) {
259 verifier()->verify_error(
260 ErrorContext::bad_type(_offset,
261 TypeOrigin::local(index, this), TypeOrigin::implicit(type1)),
262 "Bad local variable type");
263 } else {
264 subtype = type2.is_assignable_from(_locals[index + 1], verifier(), false, CHECK);
265 if (!subtype) {
266 /* Unreachable? All local store routines convert a split long or double
267 * into a TOP during the store. So we should never end up seeing an
268 * orphaned half. */
269 verifier()->verify_error(
270 ErrorContext::bad_type(_offset,
271 TypeOrigin::local(index + 1, this), TypeOrigin::implicit(type2)),
272 "Bad local variable type");
273 }
274 }
275 }
276
277 void StackMapFrame::set_local(int32_t index, VerificationType type, TRAPS) {
278 assert(!type.is_check(), "Must be a real type");
279 if (index >= _max_locals) {
280 verifier()->verify_error(
281 ErrorContext::bad_local_index(_offset, index),
282 "Local variable table overflow");
283 return;
284 }
285 // If type at index is double or long, set the next location to be unusable
286 if (_locals[index].is_double() || _locals[index].is_long()) {
287 assert((index + 1) < _locals_size, "Local variable table overflow");
288 _locals[index + 1] = VerificationType::bogus_type();
289 }
290 // If type at index is double_2 or long_2, set the previous location to be unusable
291 if (_locals[index].is_double2() || _locals[index].is_long2()) {
292 assert(index >= 1, "Local variable table underflow");
293 _locals[index - 1] = VerificationType::bogus_type();
294 }
295 _locals[index] = type;
296 if (index >= _locals_size) {
297 #ifdef ASSERT
298 for (int i=_locals_size; i<index; i++) {
299 assert(_locals[i] == VerificationType::bogus_type(),
300 "holes must be bogus type");
301 }
302 #endif
303 _locals_size = index + 1;
304 }
305 }
306
307 void StackMapFrame::set_local_2(
308 int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
309 assert(type1.is_long() || type1.is_double(), "must be long/double");
310 assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
311 if (index >= _max_locals - 1) {
312 verifier()->verify_error(
313 ErrorContext::bad_local_index(_offset, index),
314 "Local variable table overflow");
315 return;
316 }
317 // If type at index+1 is double or long, set the next location to be unusable
318 if (_locals[index+1].is_double() || _locals[index+1].is_long()) {
319 assert((index + 2) < _locals_size, "Local variable table overflow");
320 _locals[index + 2] = VerificationType::bogus_type();
321 }
322 // If type at index is double_2 or long_2, set the previous location to be unusable
323 if (_locals[index].is_double2() || _locals[index].is_long2()) {
324 assert(index >= 1, "Local variable table underflow");
325 _locals[index - 1] = VerificationType::bogus_type();
326 }
327 _locals[index] = type1;
328 _locals[index+1] = type2;
329 if (index >= _locals_size - 1) {
330 #ifdef ASSERT
331 for (int i=_locals_size; i<index; i++) {
332 assert(_locals[i] == VerificationType::bogus_type(),
333 "holes must be bogus type");
334 }
335 #endif
336 _locals_size = index + 2;
337 }
338 }
339
340 TypeOrigin StackMapFrame::stack_top_ctx() {
341 return TypeOrigin::stack(_stack_size, this);
342 }
343
344 void StackMapFrame::print_on(outputStream* str) const {
345 str->indent().print_cr("bci: @%d", _offset);
346 str->indent().print_cr("flags: {%s }",
347 flag_this_uninit() ? " flagThisUninit" : "");
348 str->indent().print("locals: {");
349 for (int32_t i = 0; i < _locals_size; ++i) {
350 str->print(" ");
351 _locals[i].print_on(str);
352 if (i != _locals_size - 1) {
353 str->print(",");
354 }
355 }
356 str->print_cr(" }");
357 str->indent().print("stack: {");
358 for (int32_t j = 0; j < _stack_size; ++j) {
359 str->print(" ");
360 _stack[j].print_on(str);
361 if (j != _stack_size - 1) {
362 str->print(",");
363 }
364 }
365 str->print_cr(" }");
366 }