1 /*
2 * Copyright (c) 1999, 2010, 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 "incls/_precompiled.incl"
26 #include "incls/_ciStreams.cpp.incl"
27
28 // ciExceptionHandlerStream
29 //
30 // Walk over some selected set of a methods exception handlers.
31
32 // ------------------------------------------------------------------
33 // ciExceptionHandlerStream::count
34 //
35 // How many exception handlers are there in this stream?
36 //
37 // Implementation note: Compiler2 needs this functionality, so I had
38 int ciExceptionHandlerStream::count() {
39 int save_pos = _pos;
40 int save_end = _end;
41
42 int count = 0;
43
44 _pos = -1;
45 _end = _method->_handler_count;
46
47
48 next();
49 while (!is_done()) {
50 count++;
51 next();
52 }
53
54 _pos = save_pos;
55 _end = save_end;
56
57 return count;
58 }
59
60 int ciExceptionHandlerStream::count_remaining() {
61 int save_pos = _pos;
62 int save_end = _end;
63
64 int count = 0;
65
66 while (!is_done()) {
67 count++;
68 next();
69 }
70
71 _pos = save_pos;
72 _end = save_end;
73
74 return count;
75 }
76
77 // ciBytecodeStream
78 //
79 // The class is used to iterate over the bytecodes of a method.
80 // It hides the details of constant pool structure/access by
81 // providing accessors for constant pool items.
82
83 // ------------------------------------------------------------------
84 // ciBytecodeStream::next_wide_or_table
85 //
86 // Special handling for switch ops
87 Bytecodes::Code ciBytecodeStream::next_wide_or_table(Bytecodes::Code bc) {
88 switch (bc) { // Check for special bytecode handling
89 case Bytecodes::_wide:
90 // Special handling for the wide bytcode
91 // Get following bytecode; do not return wide
92 assert(Bytecodes::Code(_pc[0]) == Bytecodes::_wide, "");
93 bc = Bytecodes::java_code(_raw_bc = (Bytecodes::Code)_pc[1]);
94 assert(Bytecodes::wide_length_for(bc) > 2, "must make progress");
95 _pc += Bytecodes::wide_length_for(bc);
96 _was_wide = _pc; // Flag last wide bytecode found
97 assert(is_wide(), "accessor works right");
98 break;
99
100 case Bytecodes::_lookupswitch:
101 _pc++; // Skip wide bytecode
102 _pc += (_start-_pc)&3; // Word align
103 _table_base = (jint*)_pc; // Capture for later usage
104 // table_base[0] is default far_dest
105 // Table has 2 lead elements (default, length), then pairs of u4 values.
106 // So load table length, and compute address at end of table
107 _pc = (address)&_table_base[2+ 2*Bytes::get_Java_u4((address)&_table_base[1])];
108 break;
109
110 case Bytecodes::_tableswitch: {
111 _pc++; // Skip wide bytecode
112 _pc += (_start-_pc)&3; // Word align
113 _table_base = (jint*)_pc; // Capture for later usage
114 // table_base[0] is default far_dest
115 int lo = Bytes::get_Java_u4((address)&_table_base[1]);// Low bound
116 int hi = Bytes::get_Java_u4((address)&_table_base[2]);// High bound
117 int len = hi - lo + 1; // Dense table size
118 _pc = (address)&_table_base[3+len]; // Skip past table
119 break;
120 }
121
122 default:
123 fatal("unhandled bytecode");
124 }
125 return bc;
126 }
127
128 // ------------------------------------------------------------------
129 // ciBytecodeStream::reset_to_bci
130 void ciBytecodeStream::reset_to_bci( int bci ) {
131 _bc_start=_was_wide=0;
132 _pc = _start+bci;
133 }
134
135 // ------------------------------------------------------------------
136 // ciBytecodeStream::force_bci
137 void ciBytecodeStream::force_bci(int bci) {
138 if (bci < 0) {
139 reset_to_bci(0);
140 _bc_start = _start + bci;
141 _bc = EOBC();
142 } else {
143 reset_to_bci(bci);
144 next();
145 }
146 }
147
148
149 // ------------------------------------------------------------------
150 // Constant pool access
151 // ------------------------------------------------------------------
152
153 // ------------------------------------------------------------------
154 // ciBytecodeStream::get_klass_index
155 //
156 // If this bytecodes references a klass, return the index of the
157 // referenced klass.
158 int ciBytecodeStream::get_klass_index() const {
159 switch(cur_bc()) {
160 case Bytecodes::_ldc:
161 return get_index_u1();
162 case Bytecodes::_ldc_w:
163 case Bytecodes::_ldc2_w:
164 case Bytecodes::_checkcast:
165 case Bytecodes::_instanceof:
166 case Bytecodes::_anewarray:
167 case Bytecodes::_multianewarray:
168 case Bytecodes::_new:
169 case Bytecodes::_newarray:
170 return get_index_u2();
171 default:
172 ShouldNotReachHere();
173 return 0;
174 }
175 }
176
177 // ------------------------------------------------------------------
178 // ciBytecodeStream::get_klass
179 //
180 // If this bytecode is a new, newarray, multianewarray, instanceof,
181 // or checkcast, get the referenced klass.
182 ciKlass* ciBytecodeStream::get_klass(bool& will_link) {
183 VM_ENTRY_MARK;
184 constantPoolHandle cpool(_method->get_methodOop()->constants());
185 return CURRENT_ENV->get_klass_by_index(cpool, get_klass_index(), will_link, _holder);
186 }
187
188 // ------------------------------------------------------------------
189 // ciBytecodeStream::get_constant_raw_index
190 //
191 // If this bytecode is one of the ldc variants, get the index of the
192 // referenced constant.
193 int ciBytecodeStream::get_constant_raw_index() const {
194 // work-alike for Bytecode_loadconstant::raw_index()
195 switch (cur_bc()) {
196 case Bytecodes::_ldc:
197 return get_index_u1();
198 case Bytecodes::_ldc_w:
199 case Bytecodes::_ldc2_w:
200 return get_index_u2();
201 default:
202 ShouldNotReachHere();
203 return 0;
204 }
205 }
206
207 // ------------------------------------------------------------------
208 // ciBytecodeStream::get_constant_pool_index
209 // Decode any CP cache index into a regular pool index.
210 int ciBytecodeStream::get_constant_pool_index() const {
211 // work-alike for Bytecode_loadconstant::pool_index()
212 int index = get_constant_raw_index();
213 if (has_cache_index()) {
214 return get_cpcache()->get_pool_index(index);
215 }
216 return index;
217 }
218
219 // ------------------------------------------------------------------
220 // ciBytecodeStream::get_constant_cache_index
221 // Return the CP cache index, or -1 if there isn't any.
222 int ciBytecodeStream::get_constant_cache_index() const {
223 // work-alike for Bytecode_loadconstant::cache_index()
224 return has_cache_index() ? get_constant_raw_index() : -1;
225 }
226
227 // ------------------------------------------------------------------
228 // ciBytecodeStream::get_constant
229 //
230 // If this bytecode is one of the ldc variants, get the referenced
231 // constant.
232 ciConstant ciBytecodeStream::get_constant() {
233 int pool_index = get_constant_raw_index();
234 int cache_index = -1;
235 if (has_cache_index()) {
236 cache_index = pool_index;
237 pool_index = -1;
238 }
239 VM_ENTRY_MARK;
240 constantPoolHandle cpool(_method->get_methodOop()->constants());
241 return CURRENT_ENV->get_constant_by_index(cpool, pool_index, cache_index, _holder);
242 }
243
244 // ------------------------------------------------------------------
245 // ciBytecodeStream::get_constant_pool_tag
246 //
247 // If this bytecode is one of the ldc variants, get the referenced
248 // constant.
249 constantTag ciBytecodeStream::get_constant_pool_tag(int index) const {
250 VM_ENTRY_MARK;
251 return _method->get_methodOop()->constants()->tag_at(index);
252 }
253
254 // ------------------------------------------------------------------
255 // ciBytecodeStream::get_field_index
256 //
257 // If this is a field access bytecode, get the constant pool
258 // index of the referenced field.
259 int ciBytecodeStream::get_field_index() {
260 assert(cur_bc() == Bytecodes::_getfield ||
261 cur_bc() == Bytecodes::_putfield ||
262 cur_bc() == Bytecodes::_getstatic ||
263 cur_bc() == Bytecodes::_putstatic, "wrong bc");
264 return get_index_u2_cpcache();
265 }
266
267
268 // ------------------------------------------------------------------
269 // ciBytecodeStream::get_field
270 //
271 // If this bytecode is one of get_field, get_static, put_field,
272 // or put_static, get the referenced field.
273 ciField* ciBytecodeStream::get_field(bool& will_link) {
274 ciField* f = CURRENT_ENV->get_field_by_index(_holder, get_field_index());
275 will_link = f->will_link(_holder, _bc);
276 return f;
277 }
278
279
280 // ------------------------------------------------------------------
281 // ciBytecodeStream::get_declared_field_holder
282 //
283 // Get the declared holder of the currently referenced field.
284 //
285 // Usage note: the holder() of a ciField class returns the canonical
286 // holder of the field, rather than the holder declared in the
287 // bytecodes.
288 //
289 // There is no "will_link" result passed back. The user is responsible
290 // for checking linkability when retrieving the associated field.
291 ciInstanceKlass* ciBytecodeStream::get_declared_field_holder() {
292 VM_ENTRY_MARK;
293 constantPoolHandle cpool(_method->get_methodOop()->constants());
294 int holder_index = get_field_holder_index();
295 bool ignore;
296 return CURRENT_ENV->get_klass_by_index(cpool, holder_index, ignore, _holder)
297 ->as_instance_klass();
298 }
299
300 // ------------------------------------------------------------------
301 // ciBytecodeStream::get_field_holder_index
302 //
303 // Get the constant pool index of the declared holder of the field
304 // referenced by the current bytecode. Used for generating
305 // deoptimization information.
306 int ciBytecodeStream::get_field_holder_index() {
307 GUARDED_VM_ENTRY(
308 constantPoolOop cpool = _holder->get_instanceKlass()->constants();
309 return cpool->klass_ref_index_at(get_field_index());
310 )
311 }
312
313 // ------------------------------------------------------------------
314 // ciBytecodeStream::get_field_signature_index
315 //
316 // Get the constant pool index of the signature of the field
317 // referenced by the current bytecode. Used for generating
318 // deoptimization information.
319 int ciBytecodeStream::get_field_signature_index() {
320 VM_ENTRY_MARK;
321 constantPoolOop cpool = _holder->get_instanceKlass()->constants();
322 int nt_index = cpool->name_and_type_ref_index_at(get_field_index());
323 return cpool->signature_ref_index_at(nt_index);
324 }
325
326 // ------------------------------------------------------------------
327 // ciBytecodeStream::get_method_index
328 //
329 // If this is a method invocation bytecode, get the constant pool
330 // index of the invoked method.
331 int ciBytecodeStream::get_method_index() {
332 #ifdef ASSERT
333 switch (cur_bc()) {
334 case Bytecodes::_invokeinterface:
335 case Bytecodes::_invokevirtual:
336 case Bytecodes::_invokespecial:
337 case Bytecodes::_invokestatic:
338 case Bytecodes::_invokedynamic:
339 break;
340 default:
341 ShouldNotReachHere();
342 }
343 #endif
344 if (has_index_u4())
345 return get_index_u4(); // invokedynamic
346 return get_index_u2_cpcache();
347 }
348
349 // ------------------------------------------------------------------
350 // ciBytecodeStream::get_method
351 //
352 // If this is a method invocation bytecode, get the invoked method.
353 ciMethod* ciBytecodeStream::get_method(bool& will_link) {
354 VM_ENTRY_MARK;
355 constantPoolHandle cpool(_method->get_methodOop()->constants());
356 ciMethod* m = CURRENT_ENV->get_method_by_index(cpool, get_method_index(), cur_bc(), _holder);
357 will_link = m->is_loaded();
358 return m;
359 }
360
361 // ------------------------------------------------------------------
362 // ciBytecodeStream::get_declared_method_holder
363 //
364 // Get the declared holder of the currently referenced method.
365 //
366 // Usage note: the holder() of a ciMethod class returns the canonical
367 // holder of the method, rather than the holder declared in the
368 // bytecodes.
369 //
370 // There is no "will_link" result passed back. The user is responsible
371 // for checking linkability when retrieving the associated method.
372 ciKlass* ciBytecodeStream::get_declared_method_holder() {
373 VM_ENTRY_MARK;
374 constantPoolHandle cpool(_method->get_methodOop()->constants());
375 bool ignore;
376 // report as InvokeDynamic for invokedynamic, which is syntactically classless
377 if (cur_bc() == Bytecodes::_invokedynamic)
378 return CURRENT_ENV->get_klass_by_name(_holder, ciSymbol::java_dyn_InvokeDynamic(), false);
379 return CURRENT_ENV->get_klass_by_index(cpool, get_method_holder_index(), ignore, _holder);
380 }
381
382 // ------------------------------------------------------------------
383 // ciBytecodeStream::get_method_holder_index
384 //
385 // Get the constant pool index of the declared holder of the method
386 // referenced by the current bytecode. Used for generating
387 // deoptimization information.
388 int ciBytecodeStream::get_method_holder_index() {
389 constantPoolOop cpool = _method->get_methodOop()->constants();
390 return cpool->klass_ref_index_at(get_method_index());
391 }
392
393 // ------------------------------------------------------------------
394 // ciBytecodeStream::get_method_signature_index
395 //
396 // Get the constant pool index of the signature of the method
397 // referenced by the current bytecode. Used for generating
398 // deoptimization information.
399 int ciBytecodeStream::get_method_signature_index() {
400 VM_ENTRY_MARK;
401 constantPoolOop cpool = _holder->get_instanceKlass()->constants();
402 int method_index = get_method_index();
403 int name_and_type_index = cpool->name_and_type_ref_index_at(method_index);
404 return cpool->signature_ref_index_at(name_and_type_index);
405 }
406
407 // ------------------------------------------------------------------
408 // ciBytecodeStream::get_cpcache
409 ciCPCache* ciBytecodeStream::get_cpcache() const {
410 if (_cpcache == NULL) {
411 VM_ENTRY_MARK;
412 // Get the constant pool.
413 constantPoolOop cpool = _holder->get_instanceKlass()->constants();
414 constantPoolCacheOop cpcache = cpool->cache();
415
416 *(ciCPCache**)&_cpcache = CURRENT_ENV->get_object(cpcache)->as_cpcache();
417 }
418 return _cpcache;
419 }
420
421 // ------------------------------------------------------------------
422 // ciBytecodeStream::get_call_site
423 ciCallSite* ciBytecodeStream::get_call_site() {
424 VM_ENTRY_MARK;
425 // Get the constant pool.
426 constantPoolOop cpool = _holder->get_instanceKlass()->constants();
427 constantPoolCacheOop cpcache = cpool->cache();
428
429 // Get the CallSite from the constant pool cache.
430 int method_index = get_method_index();
431 ConstantPoolCacheEntry* cpcache_entry = cpcache->secondary_entry_at(method_index);
432 oop call_site_oop = cpcache_entry->f1();
433
434 // Create a CallSite object and return it.
435 return CURRENT_ENV->get_object(call_site_oop)->as_call_site();
436 }