Mon, 17 Sep 2012 07:36:31 -0400
7194254: jstack reports wrong thread priorities
Reviewed-by: dholmes, sla, fparain
Contributed-by: Dmytro Sheyko <dmytro_sheyko@hotmail.com>
1 /*
2 * Copyright (c) 1997, 2012, 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 #ifndef SHARE_VM_RUNTIME_SHAREDRUNTIME_HPP
26 #define SHARE_VM_RUNTIME_SHAREDRUNTIME_HPP
28 #include "interpreter/bytecodeHistogram.hpp"
29 #include "interpreter/bytecodeTracer.hpp"
30 #include "interpreter/linkResolver.hpp"
31 #include "memory/allocation.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "runtime/threadLocalStorage.hpp"
34 #include "utilities/hashtable.hpp"
36 class AdapterHandlerEntry;
37 class AdapterHandlerTable;
38 class AdapterFingerPrint;
39 class vframeStream;
41 // Runtime is the base class for various runtime interfaces
42 // (InterpreterRuntime, CompilerRuntime, etc.). It provides
43 // shared functionality such as exception forwarding (C++ to
44 // Java exceptions), locking/unlocking mechanisms, statistical
45 // information, etc.
47 class SharedRuntime: AllStatic {
48 friend class VMStructs;
50 private:
51 static methodHandle resolve_sub_helper(JavaThread *thread,
52 bool is_virtual,
53 bool is_optimized, TRAPS);
55 // Shared stub locations
57 static RuntimeStub* _wrong_method_blob;
58 static RuntimeStub* _ic_miss_blob;
59 static RuntimeStub* _resolve_opt_virtual_call_blob;
60 static RuntimeStub* _resolve_virtual_call_blob;
61 static RuntimeStub* _resolve_static_call_blob;
63 static DeoptimizationBlob* _deopt_blob;
65 static SafepointBlob* _polling_page_safepoint_handler_blob;
66 static SafepointBlob* _polling_page_return_handler_blob;
68 #ifdef COMPILER2
69 static UncommonTrapBlob* _uncommon_trap_blob;
70 #endif // COMPILER2
72 #ifndef PRODUCT
73 // Counters
74 static int _nof_megamorphic_calls; // total # of megamorphic calls (through vtable)
75 #endif // !PRODUCT
77 private:
78 static SafepointBlob* generate_handler_blob(address call_ptr, bool cause_return);
79 static RuntimeStub* generate_resolve_blob(address destination, const char* name);
81 public:
82 static void generate_stubs(void);
84 // max bytes for each dtrace string parameter
85 enum { max_dtrace_string_size = 256 };
87 // The following arithmetic routines are used on platforms that do
88 // not have machine instructions to implement their functionality.
89 // Do not remove these.
91 // long arithmetics
92 static jlong lmul(jlong y, jlong x);
93 static jlong ldiv(jlong y, jlong x);
94 static jlong lrem(jlong y, jlong x);
96 // float and double remainder
97 static jfloat frem(jfloat x, jfloat y);
98 static jdouble drem(jdouble x, jdouble y);
100 #ifdef __SOFTFP__
101 static jfloat fadd(jfloat x, jfloat y);
102 static jfloat fsub(jfloat x, jfloat y);
103 static jfloat fmul(jfloat x, jfloat y);
104 static jfloat fdiv(jfloat x, jfloat y);
106 static jdouble dadd(jdouble x, jdouble y);
107 static jdouble dsub(jdouble x, jdouble y);
108 static jdouble dmul(jdouble x, jdouble y);
109 static jdouble ddiv(jdouble x, jdouble y);
110 #endif // __SOFTFP__
112 // float conversion (needs to set appropriate rounding mode)
113 static jint f2i (jfloat x);
114 static jlong f2l (jfloat x);
115 static jint d2i (jdouble x);
116 static jlong d2l (jdouble x);
117 static jfloat d2f (jdouble x);
118 static jfloat l2f (jlong x);
119 static jdouble l2d (jlong x);
121 #ifdef __SOFTFP__
122 static jfloat i2f (jint x);
123 static jdouble i2d (jint x);
124 static jdouble f2d (jfloat x);
125 #endif // __SOFTFP__
127 // double trigonometrics and transcendentals
128 static jdouble dsin(jdouble x);
129 static jdouble dcos(jdouble x);
130 static jdouble dtan(jdouble x);
131 static jdouble dlog(jdouble x);
132 static jdouble dlog10(jdouble x);
133 static jdouble dexp(jdouble x);
134 static jdouble dpow(jdouble x, jdouble y);
136 #if defined(__SOFTFP__) || defined(E500V2)
137 static double dabs(double f);
138 #endif
140 #if defined(__SOFTFP__) || defined(PPC)
141 static double dsqrt(double f);
142 #endif
144 #ifdef __SOFTFP__
145 // C++ compiler generates soft float instructions as well as passing
146 // float and double in registers.
147 static int fcmpl(float x, float y);
148 static int fcmpg(float x, float y);
149 static int dcmpl(double x, double y);
150 static int dcmpg(double x, double y);
152 static int unordered_fcmplt(float x, float y);
153 static int unordered_dcmplt(double x, double y);
154 static int unordered_fcmple(float x, float y);
155 static int unordered_dcmple(double x, double y);
156 static int unordered_fcmpge(float x, float y);
157 static int unordered_dcmpge(double x, double y);
158 static int unordered_fcmpgt(float x, float y);
159 static int unordered_dcmpgt(double x, double y);
161 static float fneg(float f);
162 static double dneg(double f);
163 #endif
165 // exception handling across interpreter/compiler boundaries
166 static address raw_exception_handler_for_return_address(JavaThread* thread, address return_address);
167 static address exception_handler_for_return_address(JavaThread* thread, address return_address);
169 #ifndef SERIALGC
170 // G1 write barriers
171 static void g1_wb_pre(oopDesc* orig, JavaThread *thread);
172 static void g1_wb_post(void* card_addr, JavaThread* thread);
173 #endif // !SERIALGC
175 // exception handling and implicit exceptions
176 static address compute_compiled_exc_handler(nmethod* nm, address ret_pc, Handle& exception,
177 bool force_unwind, bool top_frame_only);
178 enum ImplicitExceptionKind {
179 IMPLICIT_NULL,
180 IMPLICIT_DIVIDE_BY_ZERO,
181 STACK_OVERFLOW
182 };
183 static void throw_AbstractMethodError(JavaThread* thread);
184 static void throw_IncompatibleClassChangeError(JavaThread* thread);
185 static void throw_ArithmeticException(JavaThread* thread);
186 static void throw_NullPointerException(JavaThread* thread);
187 static void throw_NullPointerException_at_call(JavaThread* thread);
188 static void throw_StackOverflowError(JavaThread* thread);
189 static address continuation_for_implicit_exception(JavaThread* thread,
190 address faulting_pc,
191 ImplicitExceptionKind exception_kind);
193 // Shared stub locations
194 static address get_poll_stub(address pc);
196 static address get_ic_miss_stub() {
197 assert(_ic_miss_blob!= NULL, "oops");
198 return _ic_miss_blob->entry_point();
199 }
201 static address get_handle_wrong_method_stub() {
202 assert(_wrong_method_blob!= NULL, "oops");
203 return _wrong_method_blob->entry_point();
204 }
206 #ifdef COMPILER2
207 static void generate_uncommon_trap_blob(void);
208 static UncommonTrapBlob* uncommon_trap_blob() { return _uncommon_trap_blob; }
209 #endif // COMPILER2
211 static address get_resolve_opt_virtual_call_stub(){
212 assert(_resolve_opt_virtual_call_blob != NULL, "oops");
213 return _resolve_opt_virtual_call_blob->entry_point();
214 }
215 static address get_resolve_virtual_call_stub() {
216 assert(_resolve_virtual_call_blob != NULL, "oops");
217 return _resolve_virtual_call_blob->entry_point();
218 }
219 static address get_resolve_static_call_stub() {
220 assert(_resolve_static_call_blob != NULL, "oops");
221 return _resolve_static_call_blob->entry_point();
222 }
224 static SafepointBlob* polling_page_return_handler_blob() { return _polling_page_return_handler_blob; }
225 static SafepointBlob* polling_page_safepoint_handler_blob() { return _polling_page_safepoint_handler_blob; }
227 // Counters
228 #ifndef PRODUCT
229 static address nof_megamorphic_calls_addr() { return (address)&_nof_megamorphic_calls; }
230 #endif // PRODUCT
232 // Helper routine for full-speed JVMTI exception throwing support
233 static void throw_and_post_jvmti_exception(JavaThread *thread, Handle h_exception);
234 static void throw_and_post_jvmti_exception(JavaThread *thread, Symbol* name, const char *message = NULL);
236 // RedefineClasses() tracing support for obsolete method entry
237 static int rc_trace_method_entry(JavaThread* thread, Method* m);
239 // To be used as the entry point for unresolved native methods.
240 static address native_method_throw_unsatisfied_link_error_entry();
241 static address native_method_throw_unsupported_operation_exception_entry();
243 // bytecode tracing is only used by the TraceBytecodes
244 static intptr_t trace_bytecode(JavaThread* thread, intptr_t preserve_this_value, intptr_t tos, intptr_t tos2) PRODUCT_RETURN0;
246 // Used to back off a spin lock that is under heavy contention
247 static void yield_all(JavaThread* thread, int attempts = 0);
249 static oop retrieve_receiver( Symbol* sig, frame caller );
251 static void register_finalizer(JavaThread* thread, oopDesc* obj);
253 // dtrace notifications
254 static int dtrace_object_alloc(oopDesc* o);
255 static int dtrace_object_alloc_base(Thread* thread, oopDesc* o);
256 static int dtrace_method_entry(JavaThread* thread, Method* m);
257 static int dtrace_method_exit(JavaThread* thread, Method* m);
259 // Utility method for retrieving the Java thread id, returns 0 if the
260 // thread is not a well formed Java thread.
261 static jlong get_java_tid(Thread* thread);
264 // used by native wrappers to reenable yellow if overflow happened in native code
265 static void reguard_yellow_pages();
267 /**
268 * Fill in the "X cannot be cast to a Y" message for ClassCastException
269 *
270 * @param thr the current thread
271 * @param name the name of the class of the object attempted to be cast
272 * @return the dynamically allocated exception message (must be freed
273 * by the caller using a resource mark)
274 *
275 * BCP must refer to the current 'checkcast' opcode for the frame
276 * on top of the stack.
277 * The caller (or one of it's callers) must use a ResourceMark
278 * in order to correctly free the result.
279 */
280 static char* generate_class_cast_message(JavaThread* thr, const char* name);
282 /**
283 * Fill in the "X cannot be cast to a Y" message for ClassCastException
284 *
285 * @param name the name of the class of the object attempted to be cast
286 * @param klass the name of the target klass attempt
287 * @param gripe the specific kind of problem being reported
288 * @return the dynamically allocated exception message (must be freed
289 * by the caller using a resource mark)
290 *
291 * This version does not require access the frame, so it can be called
292 * from interpreted code
293 * The caller (or one of it's callers) must use a ResourceMark
294 * in order to correctly free the result.
295 */
296 static char* generate_class_cast_message(const char* name, const char* klass,
297 const char* gripe = " cannot be cast to ");
299 // Resolves a call site- may patch in the destination of the call into the
300 // compiled code.
301 static methodHandle resolve_helper(JavaThread *thread,
302 bool is_virtual,
303 bool is_optimized, TRAPS);
305 private:
306 // deopt blob
307 static void generate_deopt_blob(void);
309 public:
310 static DeoptimizationBlob* deopt_blob(void) { return _deopt_blob; }
312 // Resets a call-site in compiled code so it will get resolved again.
313 static methodHandle reresolve_call_site(JavaThread *thread, TRAPS);
315 // In the code prolog, if the klass comparison fails, the inline cache
316 // misses and the call site is patched to megamorphic
317 static methodHandle handle_ic_miss_helper(JavaThread* thread, TRAPS);
319 // Find the method that called us.
320 static methodHandle find_callee_method(JavaThread* thread, TRAPS);
323 private:
324 static Handle find_callee_info(JavaThread* thread,
325 Bytecodes::Code& bc,
326 CallInfo& callinfo, TRAPS);
327 static Handle find_callee_info_helper(JavaThread* thread,
328 vframeStream& vfst,
329 Bytecodes::Code& bc,
330 CallInfo& callinfo, TRAPS);
332 static address clean_virtual_call_entry();
333 static address clean_opt_virtual_call_entry();
334 static address clean_static_call_entry();
336 public:
338 // Read the array of BasicTypes from a Java signature, and compute where
339 // compiled Java code would like to put the results. Values in reg_lo and
340 // reg_hi refer to 4-byte quantities. Values less than SharedInfo::stack0 are
341 // registers, those above refer to 4-byte stack slots. All stack slots are
342 // based off of the window top. SharedInfo::stack0 refers to the first usable
343 // slot in the bottom of the frame. SharedInfo::stack0+1 refers to the memory word
344 // 4-bytes higher. So for sparc because the register window save area is at
345 // the bottom of the frame the first 16 words will be skipped and SharedInfo::stack0
346 // will be just above it. (
347 // return value is the maximum number of VMReg stack slots the convention will use.
348 static int java_calling_convention(const BasicType *sig_bt, VMRegPair *regs, int total_args_passed, int is_outgoing);
350 // Ditto except for calling C
351 static int c_calling_convention(const BasicType *sig_bt, VMRegPair *regs, int total_args_passed);
353 // Generate I2C and C2I adapters. These adapters are simple argument marshalling
354 // blobs. Unlike adapters in the tiger and earlier releases the code in these
355 // blobs does not create a new frame and are therefore virtually invisible
356 // to the stack walking code. In general these blobs extend the callers stack
357 // as needed for the conversion of argument locations.
359 // When calling a c2i blob the code will always call the interpreter even if
360 // by the time we reach the blob there is compiled code available. This allows
361 // the blob to pass the incoming stack pointer (the sender sp) in a known
362 // location for the interpreter to record. This is used by the frame code
363 // to correct the sender code to match up with the stack pointer when the
364 // thread left the compiled code. In addition it allows the interpreter
365 // to remove the space the c2i adapter allocated to do it argument conversion.
367 // Although a c2i blob will always run interpreted even if compiled code is
368 // present if we see that compiled code is present the compiled call site
369 // will be patched/re-resolved so that later calls will run compiled.
371 // Aditionally a c2i blob need to have a unverified entry because it can be reached
372 // in situations where the call site is an inlined cache site and may go megamorphic.
374 // A i2c adapter is simpler than the c2i adapter. This is because it is assumed
375 // that the interpreter before it does any call dispatch will record the current
376 // stack pointer in the interpreter frame. On return it will restore the stack
377 // pointer as needed. This means the i2c adapter code doesn't need any special
378 // handshaking path with compiled code to keep the stack walking correct.
380 static AdapterHandlerEntry* generate_i2c2i_adapters(MacroAssembler *_masm,
381 int total_args_passed,
382 int max_arg,
383 const BasicType *sig_bt,
384 const VMRegPair *regs,
385 AdapterFingerPrint* fingerprint);
387 // OSR support
389 // OSR_migration_begin will extract the jvm state from an interpreter
390 // frame (locals, monitors) and store the data in a piece of C heap
391 // storage. This then allows the interpreter frame to be removed from the
392 // stack and the OSR nmethod to be called. That method is called with a
393 // pointer to the C heap storage. This pointer is the return value from
394 // OSR_migration_begin.
396 static intptr_t* OSR_migration_begin( JavaThread *thread);
398 // OSR_migration_end is a trivial routine. It is called after the compiled
399 // method has extracted the jvm state from the C heap that OSR_migration_begin
400 // created. It's entire job is to simply free this storage.
401 static void OSR_migration_end ( intptr_t* buf);
403 // Convert a sig into a calling convention register layout
404 // and find interesting things about it.
405 static VMRegPair* find_callee_arguments(Symbol* sig, bool has_receiver, int *arg_size);
406 static VMReg name_for_receiver();
408 // "Top of Stack" slots that may be unused by the calling convention but must
409 // otherwise be preserved.
410 // On Intel these are not necessary and the value can be zero.
411 // On Sparc this describes the words reserved for storing a register window
412 // when an interrupt occurs.
413 static uint out_preserve_stack_slots();
415 // Save and restore a native result
416 static void save_native_result(MacroAssembler *_masm, BasicType ret_type, int frame_slots );
417 static void restore_native_result(MacroAssembler *_masm, BasicType ret_type, int frame_slots );
419 // Generate a native wrapper for a given method. The method takes arguments
420 // in the Java compiled code convention, marshals them to the native
421 // convention (handlizes oops, etc), transitions to native, makes the call,
422 // returns to java state (possibly blocking), unhandlizes any result and
423 // returns.
424 //
425 // The wrapper may contain special-case code if the given method
426 // is a JNI critical method, or a compiled method handle adapter,
427 // such as _invokeBasic, _linkToVirtual, etc.
428 static nmethod *generate_native_wrapper(MacroAssembler* masm,
429 methodHandle method,
430 int compile_id,
431 int total_args_passed,
432 int max_arg,
433 BasicType *sig_bt,
434 VMRegPair *regs,
435 BasicType ret_type );
437 // Block before entering a JNI critical method
438 static void block_for_jni_critical(JavaThread* thread);
440 #ifdef HAVE_DTRACE_H
441 // Generate a dtrace wrapper for a given method. The method takes arguments
442 // in the Java compiled code convention, marshals them to the native
443 // convention (handlizes oops, etc), transitions to native, makes the call,
444 // returns to java state (possibly blocking), unhandlizes any result and
445 // returns.
446 static nmethod *generate_dtrace_nmethod(MacroAssembler* masm,
447 methodHandle method);
449 // dtrace support to convert a Java string to utf8
450 static void get_utf(oopDesc* src, address dst);
451 #endif // def HAVE_DTRACE_H
453 // A compiled caller has just called the interpreter, but compiled code
454 // exists. Patch the caller so he no longer calls into the interpreter.
455 static void fixup_callers_callsite(Method* moop, address ret_pc);
457 // Slow-path Locking and Unlocking
458 static void complete_monitor_locking_C(oopDesc* obj, BasicLock* lock, JavaThread* thread);
459 static void complete_monitor_unlocking_C(oopDesc* obj, BasicLock* lock);
461 // Resolving of calls
462 static address resolve_static_call_C (JavaThread *thread);
463 static address resolve_virtual_call_C (JavaThread *thread);
464 static address resolve_opt_virtual_call_C(JavaThread *thread);
466 // arraycopy, the non-leaf version. (See StubRoutines for all the leaf calls.)
467 static void slow_arraycopy_C(oopDesc* src, jint src_pos,
468 oopDesc* dest, jint dest_pos,
469 jint length, JavaThread* thread);
471 // handle ic miss with caller being compiled code
472 // wrong method handling (inline cache misses, zombie methods)
473 static address handle_wrong_method(JavaThread* thread);
474 static address handle_wrong_method_ic_miss(JavaThread* thread);
476 #ifndef PRODUCT
478 // Collect and print inline cache miss statistics
479 private:
480 enum { maxICmiss_count = 100 };
481 static int _ICmiss_index; // length of IC miss histogram
482 static int _ICmiss_count[maxICmiss_count]; // miss counts
483 static address _ICmiss_at[maxICmiss_count]; // miss addresses
484 static void trace_ic_miss(address at);
486 public:
487 static int _monitor_enter_ctr; // monitor enter slow
488 static int _monitor_exit_ctr; // monitor exit slow
489 static int _throw_null_ctr; // throwing a null-pointer exception
490 static int _ic_miss_ctr; // total # of IC misses
491 static int _wrong_method_ctr;
492 static int _resolve_static_ctr;
493 static int _resolve_virtual_ctr;
494 static int _resolve_opt_virtual_ctr;
495 static int _implicit_null_throws;
496 static int _implicit_div0_throws;
498 static int _jbyte_array_copy_ctr; // Slow-path byte array copy
499 static int _jshort_array_copy_ctr; // Slow-path short array copy
500 static int _jint_array_copy_ctr; // Slow-path int array copy
501 static int _jlong_array_copy_ctr; // Slow-path long array copy
502 static int _oop_array_copy_ctr; // Slow-path oop array copy
503 static int _checkcast_array_copy_ctr; // Slow-path oop array copy, with cast
504 static int _unsafe_array_copy_ctr; // Slow-path includes alignment checks
505 static int _generic_array_copy_ctr; // Slow-path includes type decoding
506 static int _slow_array_copy_ctr; // Slow-path failed out to a method call
508 static int _new_instance_ctr; // 'new' object requires GC
509 static int _new_array_ctr; // 'new' array requires GC
510 static int _multi1_ctr, _multi2_ctr, _multi3_ctr, _multi4_ctr, _multi5_ctr;
511 static int _find_handler_ctr; // find exception handler
512 static int _rethrow_ctr; // rethrow exception
513 static int _mon_enter_stub_ctr; // monitor enter stub
514 static int _mon_exit_stub_ctr; // monitor exit stub
515 static int _mon_enter_ctr; // monitor enter slow
516 static int _mon_exit_ctr; // monitor exit slow
517 static int _partial_subtype_ctr; // SubRoutines::partial_subtype_check
519 // Statistics code
520 // stats for "normal" compiled calls (non-interface)
521 static int _nof_normal_calls; // total # of calls
522 static int _nof_optimized_calls; // total # of statically-bound calls
523 static int _nof_inlined_calls; // total # of inlined normal calls
524 static int _nof_static_calls; // total # of calls to static methods or super methods (invokespecial)
525 static int _nof_inlined_static_calls; // total # of inlined static calls
526 // stats for compiled interface calls
527 static int _nof_interface_calls; // total # of compiled calls
528 static int _nof_optimized_interface_calls; // total # of statically-bound interface calls
529 static int _nof_inlined_interface_calls; // total # of inlined interface calls
530 static int _nof_megamorphic_interface_calls;// total # of megamorphic interface calls
531 // stats for runtime exceptions
532 static int _nof_removable_exceptions; // total # of exceptions that could be replaced by branches due to inlining
534 public: // for compiler
535 static address nof_normal_calls_addr() { return (address)&_nof_normal_calls; }
536 static address nof_optimized_calls_addr() { return (address)&_nof_optimized_calls; }
537 static address nof_inlined_calls_addr() { return (address)&_nof_inlined_calls; }
538 static address nof_static_calls_addr() { return (address)&_nof_static_calls; }
539 static address nof_inlined_static_calls_addr() { return (address)&_nof_inlined_static_calls; }
540 static address nof_interface_calls_addr() { return (address)&_nof_interface_calls; }
541 static address nof_optimized_interface_calls_addr() { return (address)&_nof_optimized_interface_calls; }
542 static address nof_inlined_interface_calls_addr() { return (address)&_nof_inlined_interface_calls; }
543 static address nof_megamorphic_interface_calls_addr() { return (address)&_nof_megamorphic_interface_calls; }
544 static void print_call_statistics(int comp_total);
545 static void print_statistics();
546 static void print_ic_miss_histogram();
548 #endif // PRODUCT
549 };
552 // ---------------------------------------------------------------------------
553 // Implementation of AdapterHandlerLibrary
554 //
555 // This library manages argument marshaling adapters and native wrappers.
556 // There are 2 flavors of adapters: I2C and C2I.
557 //
558 // The I2C flavor takes a stock interpreted call setup, marshals the
559 // arguments for a Java-compiled call, and jumps to Rmethod-> code()->
560 // code_begin(). It is broken to call it without an nmethod assigned.
561 // The usual behavior is to lift any register arguments up out of the
562 // stack and possibly re-pack the extra arguments to be contigious.
563 // I2C adapters will save what the interpreter's stack pointer will be
564 // after arguments are popped, then adjust the interpreter's frame
565 // size to force alignment and possibly to repack the arguments.
566 // After re-packing, it jumps to the compiled code start. There are
567 // no safepoints in this adapter code and a GC cannot happen while
568 // marshaling is in progress.
569 //
570 // The C2I flavor takes a stock compiled call setup plus the target method in
571 // Rmethod, marshals the arguments for an interpreted call and jumps to
572 // Rmethod->_i2i_entry. On entry, the interpreted frame has not yet been
573 // setup. Compiled frames are fixed-size and the args are likely not in the
574 // right place. Hence all the args will likely be copied into the
575 // interpreter's frame, forcing that frame to grow. The compiled frame's
576 // outgoing stack args will be dead after the copy.
577 //
578 // Native wrappers, like adapters, marshal arguments. Unlike adapters they
579 // also perform an offical frame push & pop. They have a call to the native
580 // routine in their middles and end in a return (instead of ending in a jump).
581 // The native wrappers are stored in real nmethods instead of the BufferBlobs
582 // used by the adapters. The code generation happens here because it's very
583 // similar to what the adapters have to do.
585 class AdapterHandlerEntry : public BasicHashtableEntry<mtCode> {
586 friend class AdapterHandlerTable;
588 private:
589 AdapterFingerPrint* _fingerprint;
590 address _i2c_entry;
591 address _c2i_entry;
592 address _c2i_unverified_entry;
594 #ifdef ASSERT
595 // Captures code and signature used to generate this adapter when
596 // verifing adapter equivalence.
597 unsigned char* _saved_code;
598 int _code_length;
599 BasicType* _saved_sig;
600 int _total_args_passed;
601 #endif
603 void init(AdapterFingerPrint* fingerprint, address i2c_entry, address c2i_entry, address c2i_unverified_entry) {
604 _fingerprint = fingerprint;
605 _i2c_entry = i2c_entry;
606 _c2i_entry = c2i_entry;
607 _c2i_unverified_entry = c2i_unverified_entry;
608 #ifdef ASSERT
609 _saved_code = NULL;
610 _code_length = 0;
611 _saved_sig = NULL;
612 _total_args_passed = 0;
613 #endif
614 }
616 void deallocate();
618 // should never be used
619 AdapterHandlerEntry();
621 public:
622 address get_i2c_entry() const { return _i2c_entry; }
623 address get_c2i_entry() const { return _c2i_entry; }
624 address get_c2i_unverified_entry() const { return _c2i_unverified_entry; }
626 address base_address();
627 void relocate(address new_base);
629 AdapterFingerPrint* fingerprint() const { return _fingerprint; }
631 AdapterHandlerEntry* next() {
632 return (AdapterHandlerEntry*)BasicHashtableEntry<mtCode>::next();
633 }
635 #ifdef ASSERT
636 // Used to verify that code generated for shared adapters is equivalent
637 void save_code(unsigned char* code, int length, int total_args_passed, BasicType* sig_bt);
638 bool compare_code(unsigned char* code, int length, int total_args_passed, BasicType* sig_bt);
639 #endif
641 //virtual void print_on(outputStream* st) const; DO NOT USE
642 void print_adapter_on(outputStream* st) const;
643 };
645 class AdapterHandlerLibrary: public AllStatic {
646 private:
647 static BufferBlob* _buffer; // the temporary code buffer in CodeCache
648 static AdapterHandlerTable* _adapters;
649 static AdapterHandlerEntry* _abstract_method_handler;
650 static BufferBlob* buffer_blob();
651 static void initialize();
653 public:
655 static AdapterHandlerEntry* new_entry(AdapterFingerPrint* fingerprint,
656 address i2c_entry, address c2i_entry, address c2i_unverified_entry);
657 static nmethod* create_native_wrapper(methodHandle method, int compile_id);
658 static AdapterHandlerEntry* get_adapter(methodHandle method);
660 #ifdef HAVE_DTRACE_H
661 static nmethod* create_dtrace_nmethod (methodHandle method);
662 #endif // HAVE_DTRACE_H
664 static void print_handler(CodeBlob* b) { print_handler_on(tty, b); }
665 static void print_handler_on(outputStream* st, CodeBlob* b);
666 static bool contains(CodeBlob* b);
667 #ifndef PRODUCT
668 static void print_statistics();
669 #endif /* PRODUCT */
671 };
673 #endif // SHARE_VM_RUNTIME_SHAREDRUNTIME_HPP