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24 
25 #ifndef SHARE_VM_OOPS_CONSTMETHODOOP_HPP
26 #define SHARE_VM_OOPS_CONSTMETHODOOP_HPP
27 
28 #include "oops/oop.hpp"
29 
30 // An ConstMethod* represents portions of a Java method which
31 // do not vary.
32 //
33 // Memory layout (each line represents a word). Note that most
34 // applications load thousands of methods, so keeping the size of this
35 // structure small has a big impact on footprint.
36 //
37 // |------------------------------------------------------|
38 // | header                                               |
39 // | klass                                                |
40 // |------------------------------------------------------|
41 // | fingerprint 1                                        |
42 // | fingerprint 2                                        |
43 // | constants                      (oop)                 |
44 // | stackmap_data                  (oop)                 |
45 // | constMethod_size                                     |
46 // | interp_kind  | flags    | code_size                  |
47 // | name index              | signature index            |
48 // | method_idnum            | max_stack                  |
49 // | max_locals              | size_of_parameters         |
50 // |------------------------------------------------------|
51 // |                                                      |
52 // | byte codes                                           |
53 // |                                                      |
54 // |------------------------------------------------------|
55 // | compressed linenumber table                          |
56 // |  (see class CompressedLineNumberReadStream)          |
57 // |  (note that length is unknown until decompressed)    |
58 // |  (access flags bit tells whether table is present)   |
59 // |  (indexed from start of ConstMethod*)                |
60 // |  (elements not necessarily sorted!)                  |
61 // |------------------------------------------------------|
62 // | localvariable table elements + length (length last)  |
63 // |  (length is u2, elements are 6-tuples of u2)         |
64 // |  (see class LocalVariableTableElement)               |
65 // |  (access flags bit tells whether table is present)   |
66 // |  (indexed from end of ConstMethod*)                  |
67 // |------------------------------------------------------|
68 // | exception table + length (length last)               |
69 // |  (length is u2, elements are 4-tuples of u2)         |
70 // |  (see class ExceptionTableElement)                   |
71 // |  (access flags bit tells whether table is present)   |
72 // |  (indexed from end of ConstMethod*)                  |
73 // |------------------------------------------------------|
74 // | checked exceptions elements + length (length last)   |
75 // |  (length is u2, elements are u2)                     |
76 // |  (see class CheckedExceptionElement)                 |
77 // |  (access flags bit tells whether table is present)   |
78 // |  (indexed from end of ConstMethod*)                  |
79 // |------------------------------------------------------|
80 // | method parameters elements + length (length last)    |
81 // |  (length is u2, elements are u2, u4 structures)      |
82 // |  (see class MethodParametersElement)                 |
83 // |  (access flags bit tells whether table is present)   |
84 // |  (indexed from end of ConstMethod*)                  |
85 // |------------------------------------------------------|
86 // | generic signature index (u2)                         |
87 // |  (indexed from start of constMethodOop)              |
88 // |------------------------------------------------------|
89 // | annotations arrays - method, parameter, type, default|
90 // | pointer to Array<u1> if annotation is present        |
91 // |------------------------------------------------------|
92 //
93 // IMPORTANT: If anything gets added here, there need to be changes to
94 // ensure that ServicabilityAgent doesn't get broken as a result!
95 
96 
97 // Utility class describing elements in checked exceptions table inlined in Method*.
98 class CheckedExceptionElement VALUE_OBJ_CLASS_SPEC {
99  public:
100   u2 class_cp_index;
101 };
102 
103 
104 // Utility class describing elements in local variable table inlined in Method*.
105 class LocalVariableTableElement VALUE_OBJ_CLASS_SPEC {
106  public:
107   u2 start_bci;
108   u2 length;
109   u2 name_cp_index;
110   u2 descriptor_cp_index;
111   u2 signature_cp_index;
112   u2 slot;
113 };
114 
115 // Utility class describing elements in exception table
116 class ExceptionTableElement VALUE_OBJ_CLASS_SPEC {
117  public:
118   u2 start_pc;
119   u2 end_pc;
120   u2 handler_pc;
121   u2 catch_type_index;
122 };
123 
124 // Utility class describing elements in method parameters
125 class MethodParametersElement VALUE_OBJ_CLASS_SPEC {
126  public:
127   u2 name_cp_index;
128   u2 flags;
129 };
130 
131 class KlassSizeStats;
132 
133 // Class to collect the sizes of ConstMethod inline tables
134 #define INLINE_TABLES_DO(do_element)            \
135   do_element(localvariable_table_length)        \
136   do_element(compressed_linenumber_size)        \
137   do_element(exception_table_length)            \
138   do_element(checked_exceptions_length)         \
139   do_element(method_parameters_length)          \
140   do_element(generic_signature_index)           \
141   do_element(method_annotations_length)         \
142   do_element(parameter_annotations_length)      \
143   do_element(type_annotations_length)           \
144   do_element(default_annotations_length)
145 
146 #define INLINE_TABLE_DECLARE(sym)    int _##sym;
147 #define INLINE_TABLE_PARAM(sym)      int sym,
148 #define INLINE_TABLE_INIT(sym)       _##sym(sym),
149 #define INLINE_TABLE_NULL(sym)       _##sym(0),
150 #define INLINE_TABLE_ACCESSOR(sym)   int sym() const { return _##sym; }
151 
152 class InlineTableSizes : StackObj {
153   // declarations
154   INLINE_TABLES_DO(INLINE_TABLE_DECLARE)
155   int _end;
156  public:
InlineTableSizes(INLINE_TABLES_DO (INLINE_TABLE_PARAM)int end)157   InlineTableSizes(
158       INLINE_TABLES_DO(INLINE_TABLE_PARAM)
159       int end) :
160       INLINE_TABLES_DO(INLINE_TABLE_INIT)
161       _end(end) {}
162 
163   // Default constructor for no inlined tables
InlineTableSizes()164   InlineTableSizes() :
165       INLINE_TABLES_DO(INLINE_TABLE_NULL)
166       _end(0) {}
167 
168   // Accessors
169   INLINE_TABLES_DO(INLINE_TABLE_ACCESSOR)
170 };
171 #undef INLINE_TABLE_ACCESSOR
172 #undef INLINE_TABLE_NULL
173 #undef INLINE_TABLE_INIT
174 #undef INLINE_TABLE_PARAM
175 #undef INLINE_TABLE_DECLARE
176 
177 
178 class ConstMethod : public MetaspaceObj {
179   friend class VMStructs;
180 
181 public:
182   typedef enum { NORMAL, OVERPASS } MethodType;
183 
184 private:
185   enum {
186     _has_linenumber_table = 0x0001,
187     _has_checked_exceptions = 0x0002,
188     _has_localvariable_table = 0x0004,
189     _has_exception_table = 0x0008,
190     _has_generic_signature = 0x0010,
191     _has_method_parameters = 0x0020,
192     _is_overpass = 0x0040,
193     _has_method_annotations = 0x0080,
194     _has_parameter_annotations = 0x0100,
195     _has_type_annotations = 0x0200,
196     _has_default_annotations = 0x0400
197   };
198 
199   // Bit vector of signature
200   // Callers interpret 0=not initialized yet and
201   // -1=too many args to fix, must parse the slow way.
202   // The real initial value is special to account for nonatomicity of 64 bit
203   // loads and stores.  This value may updated and read without a lock by
204   // multiple threads, so is volatile.
205   volatile uint64_t _fingerprint;
206 
207   ConstantPool*     _constants;                  // Constant pool
208 
209   // Raw stackmap data for the method
210   Array<u1>*        _stackmap_data;
211 
212   int               _constMethod_size;
213   u2                _flags;
214   u1                _result_type;                 // BasicType of result
215 
216   // Size of Java bytecodes allocated immediately after Method*.
217   u2                _code_size;
218   u2                _name_index;                 // Method name (index in constant pool)
219   u2                _signature_index;            // Method signature (index in constant pool)
220   u2                _method_idnum;               // unique identification number for the method within the class
221                                                  // initially corresponds to the index into the methods array.
222                                                  // but this may change with redefinition
223   u2                _max_stack;                  // Maximum number of entries on the expression stack
224   u2                _max_locals;                 // Number of local variables used by this method
225   u2                _size_of_parameters;         // size of the parameter block (receiver + arguments) in words
226   u2                _orig_method_idnum;          // Original unique identification number for the method
227 
228   // Constructor
229   ConstMethod(int byte_code_size,
230               InlineTableSizes* sizes,
231               MethodType is_overpass,
232               int size);
233 public:
234 
235   static ConstMethod* allocate(ClassLoaderData* loader_data,
236                                int byte_code_size,
237                                InlineTableSizes* sizes,
238                                MethodType mt,
239                                TRAPS);
240 
is_constMethod() const241   bool is_constMethod() const { return true; }
242 
243   // Inlined tables
244   void set_inlined_tables_length(InlineTableSizes* sizes);
245 
has_generic_signature() const246   bool has_generic_signature() const
247     { return (_flags & _has_generic_signature) != 0; }
248 
has_linenumber_table() const249   bool has_linenumber_table() const
250     { return (_flags & _has_linenumber_table) != 0; }
251 
has_checked_exceptions() const252   bool has_checked_exceptions() const
253     { return (_flags & _has_checked_exceptions) != 0; }
254 
has_localvariable_table() const255   bool has_localvariable_table() const
256     { return (_flags & _has_localvariable_table) != 0; }
257 
has_exception_handler() const258   bool has_exception_handler() const
259     { return (_flags & _has_exception_table) != 0; }
260 
has_method_parameters() const261   bool has_method_parameters() const
262     { return (_flags & _has_method_parameters) != 0; }
263 
method_type() const264   MethodType method_type() const {
265     return ((_flags & _is_overpass) == 0) ? NORMAL : OVERPASS;
266   }
267 
set_method_type(MethodType mt)268   void set_method_type(MethodType mt) {
269     if (mt == NORMAL) {
270       _flags &= ~(_is_overpass);
271     } else {
272       _flags |= _is_overpass;
273     }
274   }
275 
276   // constant pool
constants() const277   ConstantPool* constants() const        { return _constants; }
set_constants(ConstantPool * c)278   void set_constants(ConstantPool* c)    { _constants = c; }
279 
280   Method* method() const;
281 
282   // stackmap table data
stackmap_data() const283   Array<u1>* stackmap_data() const { return _stackmap_data; }
set_stackmap_data(Array<u1> * sd)284   void set_stackmap_data(Array<u1>* sd) { _stackmap_data = sd; }
285   void copy_stackmap_data(ClassLoaderData* loader_data, u1* sd, int length, TRAPS);
has_stackmap_table() const286   bool has_stackmap_table() const { return _stackmap_data != NULL; }
287 
init_fingerprint()288   void init_fingerprint() {
289     const uint64_t initval = CONST64(0x8000000000000000);
290     _fingerprint = initval;
291   }
292 
fingerprint() const293   uint64_t fingerprint() const                   {
294     // Since reads aren't atomic for 64 bits, if any of the high or low order
295     // word is the initial value, return 0.  See init_fingerprint for initval.
296     uint high_fp = (uint)(_fingerprint >> 32);
297     if ((int) _fingerprint == 0 || high_fp == 0x80000000) {
298       return 0L;
299     } else {
300       return _fingerprint;
301     }
302   }
303 
set_fingerprint(uint64_t new_fingerprint)304   uint64_t set_fingerprint(uint64_t new_fingerprint) {
305 #ifdef ASSERT
306     // Assert only valid if complete/valid 64 bit _fingerprint value is read.
307     uint64_t oldfp = fingerprint();
308 #endif // ASSERT
309     _fingerprint = new_fingerprint;
310     assert(oldfp == 0L || new_fingerprint == oldfp,
311            "fingerprint cannot change");
312     assert(((new_fingerprint >> 32) != 0x80000000) && (int)new_fingerprint !=0,
313            "fingerprint should call init to set initial value");
314     return new_fingerprint;
315   }
316 
317   // name
name_index() const318   int name_index() const                         { return _name_index; }
set_name_index(int index)319   void set_name_index(int index)                 { _name_index = index; }
320 
321   // signature
signature_index() const322   int signature_index() const                    { return _signature_index; }
set_signature_index(int index)323   void set_signature_index(int index)            { _signature_index = index; }
324 
325   // generics support
generic_signature_index() const326   int generic_signature_index() const            {
327     if (has_generic_signature()) {
328       return *generic_signature_index_addr();
329     } else {
330       return 0;
331     }
332   }
set_generic_signature_index(u2 index)333   void set_generic_signature_index(u2 index)    {
334     assert(has_generic_signature(), "");
335     u2* addr = generic_signature_index_addr();
336     *addr = index;
337   }
338 
339   // Sizing
header_size()340   static int header_size() {
341     return sizeof(ConstMethod)/HeapWordSize;
342   }
343 
344   // Size needed
345   static int size(int code_size, InlineTableSizes* sizes);
346 
size() const347   int size() const                    { return _constMethod_size;}
set_constMethod_size(int size)348   void set_constMethod_size(int size)     { _constMethod_size = size; }
349 #if INCLUDE_SERVICES
350   void collect_statistics(KlassSizeStats *sz) const;
351 #endif
352 
353   // code size
code_size() const354   int code_size() const                          { return _code_size; }
set_code_size(int size)355   void set_code_size(int size) {
356     assert(max_method_code_size < (1 << 16),
357            "u2 is too small to hold method code size in general");
358     assert(0 <= size && size <= max_method_code_size, "invalid code size");
359     _code_size = size;
360   }
361 
362   // linenumber table - note that length is unknown until decompression,
363   // see class CompressedLineNumberReadStream.
364   u_char* compressed_linenumber_table() const;         // not preserved by gc
365   u2* generic_signature_index_addr() const;
366   u2* checked_exceptions_length_addr() const;
367   u2* localvariable_table_length_addr() const;
368   u2* exception_table_length_addr() const;
369   u2* method_parameters_length_addr() const;
370 
371   // checked exceptions
372   int checked_exceptions_length() const;
373   CheckedExceptionElement* checked_exceptions_start() const;
374 
375   // localvariable table
376   int localvariable_table_length() const;
377   LocalVariableTableElement* localvariable_table_start() const;
378 
379   // exception table
380   int exception_table_length() const;
381   ExceptionTableElement* exception_table_start() const;
382 
383   // method parameters table
384   int method_parameters_length() const;
385   MethodParametersElement* method_parameters_start() const;
386 
387   // method annotations
has_method_annotations() const388   bool has_method_annotations() const
389     { return (_flags & _has_method_annotations) != 0; }
390 
has_parameter_annotations() const391   bool has_parameter_annotations() const
392     { return (_flags & _has_parameter_annotations) != 0; }
393 
has_type_annotations() const394   bool has_type_annotations() const
395     { return (_flags & _has_type_annotations) != 0; }
396 
has_default_annotations() const397   bool has_default_annotations() const
398     { return (_flags & _has_default_annotations) != 0; }
399 
400 
401   AnnotationArray** method_annotations_addr() const;
method_annotations() const402   AnnotationArray* method_annotations() const  {
403     return has_method_annotations() ? *(method_annotations_addr()) : NULL;
404   }
set_method_annotations(AnnotationArray * anno)405   void set_method_annotations(AnnotationArray* anno) {
406     *(method_annotations_addr()) = anno;
407   }
408 
409   AnnotationArray** parameter_annotations_addr() const;
parameter_annotations() const410   AnnotationArray* parameter_annotations() const {
411     return has_parameter_annotations() ? *(parameter_annotations_addr()) : NULL;
412   }
set_parameter_annotations(AnnotationArray * anno)413   void set_parameter_annotations(AnnotationArray* anno) {
414     *(parameter_annotations_addr()) = anno;
415   }
416 
417   AnnotationArray** type_annotations_addr() const;
type_annotations() const418   AnnotationArray* type_annotations() const {
419     return has_type_annotations() ? *(type_annotations_addr()) : NULL;
420   }
set_type_annotations(AnnotationArray * anno)421   void set_type_annotations(AnnotationArray* anno) {
422     *(type_annotations_addr()) = anno;
423   }
424 
425   AnnotationArray** default_annotations_addr() const;
default_annotations() const426   AnnotationArray* default_annotations() const {
427     return has_default_annotations() ? *(default_annotations_addr()) : NULL;
428   }
set_default_annotations(AnnotationArray * anno)429   void set_default_annotations(AnnotationArray* anno) {
430     *(default_annotations_addr()) = anno;
431   }
432 
method_annotations_length() const433   int method_annotations_length() const {
434     return has_method_annotations() ? method_annotations()->length() : 0;
435   }
parameter_annotations_length() const436   int parameter_annotations_length() const {
437     return has_parameter_annotations() ? parameter_annotations()->length() : 0;
438   }
type_annotations_length() const439   int type_annotations_length() const {
440     return has_type_annotations() ? type_annotations()->length() : 0;
441   }
default_annotations_length() const442   int default_annotations_length() const {
443     return has_default_annotations() ? default_annotations()->length() : 0;
444   }
445 
446   // Copy annotations from other ConstMethod
447   void copy_annotations_from(ConstMethod* cm);
448 
449   // byte codes
set_code(address code)450   void    set_code(address code) {
451     if (code_size() > 0) {
452       memcpy(code_base(), code, code_size());
453     }
454   }
code_base() const455   address code_base() const            { return (address) (this+1); }
code_end() const456   address code_end() const             { return code_base() + code_size(); }
contains(address bcp) const457   bool    contains(address bcp) const  { return code_base() <= bcp
458                                                      && bcp < code_end(); }
459   // Offset to bytecodes
codes_offset()460   static ByteSize codes_offset()
461                             { return in_ByteSize(sizeof(ConstMethod)); }
462 
constants_offset()463   static ByteSize constants_offset()
464                             { return byte_offset_of(ConstMethod, _constants); }
465 
max_stack_offset()466   static ByteSize max_stack_offset()
467                             { return byte_offset_of(ConstMethod, _max_stack); }
size_of_locals_offset()468   static ByteSize size_of_locals_offset()
469                             { return byte_offset_of(ConstMethod, _max_locals); }
size_of_parameters_offset()470   static ByteSize size_of_parameters_offset()
471                             { return byte_offset_of(ConstMethod, _size_of_parameters); }
472 
result_type_offset()473   static ByteSize result_type_offset()
474                             { return byte_offset_of(ConstMethod, _result_type); }
475 
476   // Unique id for the method
477   static const u2 MAX_IDNUM;
478   static const u2 UNSET_IDNUM;
method_idnum() const479   u2 method_idnum() const                        { return _method_idnum; }
set_method_idnum(u2 idnum)480   void set_method_idnum(u2 idnum)                { _method_idnum = idnum; }
481 
orig_method_idnum() const482   u2 orig_method_idnum() const                   { return _orig_method_idnum; }
set_orig_method_idnum(u2 idnum)483   void set_orig_method_idnum(u2 idnum)           { _orig_method_idnum = idnum; }
484 
485   // max stack
max_stack() const486   int  max_stack() const                         { return _max_stack; }
set_max_stack(int size)487   void set_max_stack(int size)                   { _max_stack = size; }
488 
489   // max locals
max_locals() const490   int  max_locals() const                        { return _max_locals; }
set_max_locals(int size)491   void set_max_locals(int size)                  { _max_locals = size; }
492 
493   // size of parameters
size_of_parameters() const494   int  size_of_parameters() const                { return _size_of_parameters; }
set_size_of_parameters(int size)495   void set_size_of_parameters(int size)          { _size_of_parameters = size; }
496 
set_result_type(BasicType rt)497   void set_result_type(BasicType rt)             { assert(rt < 16, "result type too large");
498                                                    _result_type = (u1)rt; }
499   // Deallocation for RedefineClasses
500   void deallocate_contents(ClassLoaderData* loader_data);
is_klass() const501   bool is_klass() const { return false; }
502   DEBUG_ONLY(bool on_stack() { return false; })
503 
504 private:
505   // Since the size of the compressed line number table is unknown, the
506   // offsets of the other variable sized sections are computed backwards
507   // from the end of the ConstMethod*.
508 
509   // First byte after ConstMethod*
constMethod_end() const510   address constMethod_end() const
511                           { return (address)((intptr_t*)this + _constMethod_size); }
512 
513   // Last short in ConstMethod*
514   u2* last_u2_element() const;
515 
516  public:
517   // Printing
518   void print_on      (outputStream* st) const;
519   void print_value_on(outputStream* st) const;
520 
internal_name() const521   const char* internal_name() const { return "{constMethod}"; }
522 
523   // Verify
524   void verify_on(outputStream* st);
525 };
526 
527 #endif // SHARE_VM_OOPS_CONSTMETHODOOP_HPP
528