Tue, 03 Aug 2010 15:55:03 -0700
6973963: SEGV in ciBlock::start_bci() with EA
Summary: Added more checks into ResourceObj and growableArray to verify correctness of allocation type.
Reviewed-by: never, coleenp, dholmes
1 /*
2 * Copyright (c) 1997, 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 */
25 class CodeComments;
26 class AbstractAssembler;
27 class MacroAssembler;
28 class PhaseCFG;
29 class Compile;
30 class BufferBlob;
31 class CodeBuffer;
33 class CodeOffsets: public StackObj {
34 public:
35 enum Entries { Entry,
36 Verified_Entry,
37 Frame_Complete, // Offset in the code where the frame setup is (for forte stackwalks) is complete
38 OSR_Entry,
39 Dtrace_trap = OSR_Entry, // dtrace probes can never have an OSR entry so reuse it
40 Exceptions, // Offset where exception handler lives
41 Deopt, // Offset where deopt handler lives
42 DeoptMH, // Offset where MethodHandle deopt handler lives
43 UnwindHandler, // Offset to default unwind handler
44 max_Entries };
46 // special value to note codeBlobs where profile (forte) stack walking is
47 // always dangerous and suspect.
49 enum { frame_never_safe = -1 };
51 private:
52 int _values[max_Entries];
54 public:
55 CodeOffsets() {
56 _values[Entry ] = 0;
57 _values[Verified_Entry] = 0;
58 _values[Frame_Complete] = frame_never_safe;
59 _values[OSR_Entry ] = 0;
60 _values[Exceptions ] = -1;
61 _values[Deopt ] = -1;
62 _values[DeoptMH ] = -1;
63 _values[UnwindHandler ] = -1;
64 }
66 int value(Entries e) { return _values[e]; }
67 void set_value(Entries e, int val) { _values[e] = val; }
68 };
70 // This class represents a stream of code and associated relocations.
71 // There are a few in each CodeBuffer.
72 // They are filled concurrently, and concatenated at the end.
73 class CodeSection VALUE_OBJ_CLASS_SPEC {
74 friend class CodeBuffer;
75 public:
76 typedef int csize_t; // code size type; would be size_t except for history
78 private:
79 address _start; // first byte of contents (instructions)
80 address _mark; // user mark, usually an instruction beginning
81 address _end; // current end address
82 address _limit; // last possible (allocated) end address
83 relocInfo* _locs_start; // first byte of relocation information
84 relocInfo* _locs_end; // first byte after relocation information
85 relocInfo* _locs_limit; // first byte after relocation information buf
86 address _locs_point; // last relocated position (grows upward)
87 bool _locs_own; // did I allocate the locs myself?
88 bool _frozen; // no more expansion of this section
89 char _index; // my section number (SECT_INST, etc.)
90 CodeBuffer* _outer; // enclosing CodeBuffer
92 // (Note: _locs_point used to be called _last_reloc_offset.)
94 CodeSection() {
95 _start = NULL;
96 _mark = NULL;
97 _end = NULL;
98 _limit = NULL;
99 _locs_start = NULL;
100 _locs_end = NULL;
101 _locs_limit = NULL;
102 _locs_point = NULL;
103 _locs_own = false;
104 _frozen = false;
105 debug_only(_index = -1);
106 debug_only(_outer = (CodeBuffer*)badAddress);
107 }
109 void initialize_outer(CodeBuffer* outer, int index) {
110 _outer = outer;
111 _index = index;
112 }
114 void initialize(address start, csize_t size = 0) {
115 assert(_start == NULL, "only one init step, please");
116 _start = start;
117 _mark = NULL;
118 _end = start;
120 _limit = start + size;
121 _locs_point = start;
122 }
124 void initialize_locs(int locs_capacity);
125 void expand_locs(int new_capacity);
126 void initialize_locs_from(const CodeSection* source_cs);
128 // helper for CodeBuffer::expand()
129 void take_over_code_from(CodeSection* cs) {
130 _start = cs->_start;
131 _mark = cs->_mark;
132 _end = cs->_end;
133 _limit = cs->_limit;
134 _locs_point = cs->_locs_point;
135 }
137 public:
138 address start() const { return _start; }
139 address mark() const { return _mark; }
140 address end() const { return _end; }
141 address limit() const { return _limit; }
142 csize_t size() const { return (csize_t)(_end - _start); }
143 csize_t mark_off() const { assert(_mark != NULL, "not an offset");
144 return (csize_t)(_mark - _start); }
145 csize_t capacity() const { return (csize_t)(_limit - _start); }
146 csize_t remaining() const { return (csize_t)(_limit - _end); }
148 relocInfo* locs_start() const { return _locs_start; }
149 relocInfo* locs_end() const { return _locs_end; }
150 int locs_count() const { return (int)(_locs_end - _locs_start); }
151 relocInfo* locs_limit() const { return _locs_limit; }
152 address locs_point() const { return _locs_point; }
153 csize_t locs_point_off() const{ return (csize_t)(_locs_point - _start); }
154 csize_t locs_capacity() const { return (csize_t)(_locs_limit - _locs_start); }
155 csize_t locs_remaining()const { return (csize_t)(_locs_limit - _locs_end); }
157 int index() const { return _index; }
158 bool is_allocated() const { return _start != NULL; }
159 bool is_empty() const { return _start == _end; }
160 bool is_frozen() const { return _frozen; }
161 bool has_locs() const { return _locs_end != NULL; }
163 CodeBuffer* outer() const { return _outer; }
165 // is a given address in this section? (2nd version is end-inclusive)
166 bool contains(address pc) const { return pc >= _start && pc < _end; }
167 bool contains2(address pc) const { return pc >= _start && pc <= _end; }
168 bool allocates(address pc) const { return pc >= _start && pc < _limit; }
169 bool allocates2(address pc) const { return pc >= _start && pc <= _limit; }
171 void set_end(address pc) { assert(allocates2(pc),""); _end = pc; }
172 void set_mark(address pc) { assert(contains2(pc),"not in codeBuffer");
173 _mark = pc; }
174 void set_mark_off(int offset) { assert(contains2(offset+_start),"not in codeBuffer");
175 _mark = offset + _start; }
176 void set_mark() { _mark = _end; }
177 void clear_mark() { _mark = NULL; }
179 void set_locs_end(relocInfo* p) {
180 assert(p <= locs_limit(), "locs data fits in allocated buffer");
181 _locs_end = p;
182 }
183 void set_locs_point(address pc) {
184 assert(pc >= locs_point(), "relocation addr may not decrease");
185 assert(allocates2(pc), "relocation addr must be in this section");
186 _locs_point = pc;
187 }
189 // Share a scratch buffer for relocinfo. (Hacky; saves a resource allocation.)
190 void initialize_shared_locs(relocInfo* buf, int length);
192 // Manage labels and their addresses.
193 address target(Label& L, address branch_pc);
195 // Emit a relocation.
196 void relocate(address at, RelocationHolder const& rspec, int format = 0);
197 void relocate(address at, relocInfo::relocType rtype, int format = 0) {
198 if (rtype != relocInfo::none)
199 relocate(at, Relocation::spec_simple(rtype), format);
200 }
202 // alignment requirement for starting offset
203 // Requirements are that the instruction area and the
204 // stubs area must start on CodeEntryAlignment, and
205 // the ctable on sizeof(jdouble)
206 int alignment() const { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); }
208 // Slop between sections, used only when allocating temporary BufferBlob buffers.
209 static csize_t end_slop() { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); }
211 csize_t align_at_start(csize_t off) const { return (csize_t) align_size_up(off, alignment()); }
213 // Mark a section frozen. Assign its remaining space to
214 // the following section. It will never expand after this point.
215 inline void freeze(); // { _outer->freeze_section(this); }
217 // Ensure there's enough space left in the current section.
218 // Return true if there was an expansion.
219 bool maybe_expand_to_ensure_remaining(csize_t amount);
221 #ifndef PRODUCT
222 void decode();
223 void dump();
224 void print(const char* name);
225 #endif //PRODUCT
226 };
228 class CodeComment;
229 class CodeComments VALUE_OBJ_CLASS_SPEC {
230 private:
231 #ifndef PRODUCT
232 CodeComment* _comments;
233 #endif
235 public:
236 CodeComments() {
237 #ifndef PRODUCT
238 _comments = NULL;
239 #endif
240 }
242 void add_comment(intptr_t offset, const char * comment) PRODUCT_RETURN;
243 void print_block_comment(outputStream* stream, intptr_t offset) PRODUCT_RETURN;
244 void assign(CodeComments& other) PRODUCT_RETURN;
245 void free() PRODUCT_RETURN;
246 };
249 // A CodeBuffer describes a memory space into which assembly
250 // code is generated. This memory space usually occupies the
251 // interior of a single BufferBlob, but in some cases it may be
252 // an arbitrary span of memory, even outside the code cache.
253 //
254 // A code buffer comes in two variants:
255 //
256 // (1) A CodeBuffer referring to an already allocated piece of memory:
257 // This is used to direct 'static' code generation (e.g. for interpreter
258 // or stubroutine generation, etc.). This code comes with NO relocation
259 // information.
260 //
261 // (2) A CodeBuffer referring to a piece of memory allocated when the
262 // CodeBuffer is allocated. This is used for nmethod generation.
263 //
264 // The memory can be divided up into several parts called sections.
265 // Each section independently accumulates code (or data) an relocations.
266 // Sections can grow (at the expense of a reallocation of the BufferBlob
267 // and recopying of all active sections). When the buffered code is finally
268 // written to an nmethod (or other CodeBlob), the contents (code, data,
269 // and relocations) of the sections are padded to an alignment and concatenated.
270 // Instructions and data in one section can contain relocatable references to
271 // addresses in a sibling section.
273 class CodeBuffer: public StackObj {
274 friend class CodeSection;
276 private:
277 // CodeBuffers must be allocated on the stack except for a single
278 // special case during expansion which is handled internally. This
279 // is done to guarantee proper cleanup of resources.
280 void* operator new(size_t size) { return ResourceObj::operator new(size); }
281 void operator delete(void* p) { ShouldNotCallThis(); }
283 public:
284 typedef int csize_t; // code size type; would be size_t except for history
285 enum {
286 // Here is the list of all possible sections, in order of ascending address.
287 SECT_INSTS, // Executable instructions.
288 SECT_STUBS, // Outbound trampolines for supporting call sites.
289 SECT_CONSTS, // Non-instruction data: Floats, jump tables, etc.
290 SECT_LIMIT, SECT_NONE = -1
291 };
293 private:
294 enum {
295 sect_bits = 2, // assert (SECT_LIMIT <= (1<<sect_bits))
296 sect_mask = (1<<sect_bits)-1
297 };
299 const char* _name;
301 CodeSection _insts; // instructions (the main section)
302 CodeSection _stubs; // stubs (call site support), deopt, exception handling
303 CodeSection _consts; // constants, jump tables
305 CodeBuffer* _before_expand; // dead buffer, from before the last expansion
307 BufferBlob* _blob; // optional buffer in CodeCache for generated code
308 address _total_start; // first address of combined memory buffer
309 csize_t _total_size; // size in bytes of combined memory buffer
311 OopRecorder* _oop_recorder;
312 CodeComments _comments;
313 OopRecorder _default_oop_recorder; // override with initialize_oop_recorder
314 Arena* _overflow_arena;
316 address _decode_begin; // start address for decode
317 address decode_begin();
319 void initialize_misc(const char * name) {
320 // all pointers other than code_start/end and those inside the sections
321 assert(name != NULL, "must have a name");
322 _name = name;
323 _before_expand = NULL;
324 _blob = NULL;
325 _oop_recorder = NULL;
326 _decode_begin = NULL;
327 _overflow_arena = NULL;
328 }
330 void initialize(address code_start, csize_t code_size) {
331 _insts.initialize_outer(this, SECT_INSTS);
332 _stubs.initialize_outer(this, SECT_STUBS);
333 _consts.initialize_outer(this, SECT_CONSTS);
334 _total_start = code_start;
335 _total_size = code_size;
336 // Initialize the main section:
337 _insts.initialize(code_start, code_size);
338 assert(!_stubs.is_allocated(), "no garbage here");
339 assert(!_consts.is_allocated(), "no garbage here");
340 _oop_recorder = &_default_oop_recorder;
341 }
343 void initialize_section_size(CodeSection* cs, csize_t size);
345 void freeze_section(CodeSection* cs);
347 // helper for CodeBuffer::expand()
348 void take_over_code_from(CodeBuffer* cs);
350 #ifdef ASSERT
351 // ensure sections are disjoint, ordered, and contained in the blob
352 bool verify_section_allocation();
353 #endif
355 // copies combined relocations to the blob, returns bytes copied
356 // (if target is null, it is a dry run only, just for sizing)
357 csize_t copy_relocations_to(CodeBlob* blob) const;
359 // copies combined code to the blob (assumes relocs are already in there)
360 void copy_code_to(CodeBlob* blob);
362 // moves code sections to new buffer (assumes relocs are already in there)
363 void relocate_code_to(CodeBuffer* cb) const;
365 // set up a model of the final layout of my contents
366 void compute_final_layout(CodeBuffer* dest) const;
368 // Expand the given section so at least 'amount' is remaining.
369 // Creates a new, larger BufferBlob, and rewrites the code & relocs.
370 void expand(CodeSection* which_cs, csize_t amount);
372 // Helper for expand.
373 csize_t figure_expanded_capacities(CodeSection* which_cs, csize_t amount, csize_t* new_capacity);
375 public:
376 // (1) code buffer referring to pre-allocated instruction memory
377 CodeBuffer(address code_start, csize_t code_size);
379 // (2) code buffer allocating codeBlob memory for code & relocation
380 // info but with lazy initialization. The name must be something
381 // informative.
382 CodeBuffer(const char* name) {
383 initialize_misc(name);
384 }
387 // (3) code buffer allocating codeBlob memory for code & relocation
388 // info. The name must be something informative and code_size must
389 // include both code and stubs sizes.
390 CodeBuffer(const char* name, csize_t code_size, csize_t locs_size) {
391 initialize_misc(name);
392 initialize(code_size, locs_size);
393 }
395 ~CodeBuffer();
397 // Initialize a CodeBuffer constructed using constructor 2. Using
398 // constructor 3 is equivalent to calling constructor 2 and then
399 // calling this method. It's been factored out for convenience of
400 // construction.
401 void initialize(csize_t code_size, csize_t locs_size);
403 CodeSection* insts() { return &_insts; }
404 CodeSection* stubs() { return &_stubs; }
405 CodeSection* consts() { return &_consts; }
407 // present sections in order; return NULL at end; insts is #0, etc.
408 CodeSection* code_section(int n) {
409 // This makes the slightly questionable but portable assumption that
410 // the various members (_insts, _stubs, etc.) are adjacent in the
411 // layout of CodeBuffer.
412 CodeSection* cs = &_insts + n;
413 assert(cs->index() == n || !cs->is_allocated(), "sanity");
414 return cs;
415 }
416 const CodeSection* code_section(int n) const { // yucky const stuff
417 return ((CodeBuffer*)this)->code_section(n);
418 }
419 static const char* code_section_name(int n);
420 int section_index_of(address addr) const;
421 bool contains(address addr) const {
422 // handy for debugging
423 return section_index_of(addr) > SECT_NONE;
424 }
426 // A stable mapping between 'locators' (small ints) and addresses.
427 static int locator_pos(int locator) { return locator >> sect_bits; }
428 static int locator_sect(int locator) { return locator & sect_mask; }
429 static int locator(int pos, int sect) { return (pos << sect_bits) | sect; }
430 int locator(address addr) const;
431 address locator_address(int locator) const;
433 // Properties
434 const char* name() const { return _name; }
435 CodeBuffer* before_expand() const { return _before_expand; }
436 BufferBlob* blob() const { return _blob; }
437 void set_blob(BufferBlob* blob);
438 void free_blob(); // Free the blob, if we own one.
440 // Properties relative to the insts section:
441 address code_begin() const { return _insts.start(); }
442 address code_end() const { return _insts.end(); }
443 void set_code_end(address end) { _insts.set_end(end); }
444 address code_limit() const { return _insts.limit(); }
445 address inst_mark() const { return _insts.mark(); }
446 void set_inst_mark() { _insts.set_mark(); }
447 void clear_inst_mark() { _insts.clear_mark(); }
449 // is there anything in the buffer other than the current section?
450 bool is_pure() const { return code_size() == total_code_size(); }
452 // size in bytes of output so far in the insts sections
453 csize_t code_size() const { return _insts.size(); }
455 // same as code_size(), except that it asserts there is no non-code here
456 csize_t pure_code_size() const { assert(is_pure(), "no non-code");
457 return code_size(); }
458 // capacity in bytes of the insts sections
459 csize_t code_capacity() const { return _insts.capacity(); }
461 // number of bytes remaining in the insts section
462 csize_t code_remaining() const { return _insts.remaining(); }
464 // is a given address in the insts section? (2nd version is end-inclusive)
465 bool code_contains(address pc) const { return _insts.contains(pc); }
466 bool code_contains2(address pc) const { return _insts.contains2(pc); }
468 // allocated size of code in all sections, when aligned and concatenated
469 // (this is the eventual state of the code in its final CodeBlob)
470 csize_t total_code_size() const;
472 // combined offset (relative to start of insts) of given address,
473 // as eventually found in the final CodeBlob
474 csize_t total_offset_of(address addr) const;
476 // allocated size of all relocation data, including index, rounded up
477 csize_t total_relocation_size() const;
479 // allocated size of any and all recorded oops
480 csize_t total_oop_size() const {
481 OopRecorder* recorder = oop_recorder();
482 return (recorder == NULL)? 0: recorder->oop_size();
483 }
485 // Configuration functions, called immediately after the CB is constructed.
486 // The section sizes are subtracted from the original insts section.
487 // Note: Call them in reverse section order, because each steals from insts.
488 void initialize_consts_size(csize_t size) { initialize_section_size(&_consts, size); }
489 void initialize_stubs_size(csize_t size) { initialize_section_size(&_stubs, size); }
490 // Override default oop recorder.
491 void initialize_oop_recorder(OopRecorder* r);
493 OopRecorder* oop_recorder() const { return _oop_recorder; }
494 CodeComments& comments() { return _comments; }
496 // Code generation
497 void relocate(address at, RelocationHolder const& rspec, int format = 0) {
498 _insts.relocate(at, rspec, format);
499 }
500 void relocate(address at, relocInfo::relocType rtype, int format = 0) {
501 _insts.relocate(at, rtype, format);
502 }
504 // Management of overflow storage for binding of Labels.
505 GrowableArray<int>* create_patch_overflow();
507 // NMethod generation
508 void copy_code_and_locs_to(CodeBlob* blob) {
509 assert(blob != NULL, "sane");
510 copy_relocations_to(blob);
511 copy_code_to(blob);
512 }
513 void copy_oops_to(nmethod* nm) {
514 if (!oop_recorder()->is_unused()) {
515 oop_recorder()->copy_to(nm);
516 }
517 }
519 // Transform an address from the code in this code buffer to a specified code buffer
520 address transform_address(const CodeBuffer &cb, address addr) const;
522 void block_comment(intptr_t offset, const char * comment) PRODUCT_RETURN;
524 #ifndef PRODUCT
525 public:
526 // Printing / Decoding
527 // decodes from decode_begin() to code_end() and sets decode_begin to end
528 void decode();
529 void decode_all(); // decodes all the code
530 void skip_decode(); // sets decode_begin to code_end();
531 void print();
532 #endif
535 // The following header contains architecture-specific implementations
536 #include "incls/_codeBuffer_pd.hpp.incl"
537 };
540 inline void CodeSection::freeze() {
541 _outer->freeze_section(this);
542 }
544 inline bool CodeSection::maybe_expand_to_ensure_remaining(csize_t amount) {
545 if (remaining() < amount) { _outer->expand(this, amount); return true; }
546 return false;
547 }