1 /*
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   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
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  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.
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  24 
  25 #ifndef SHARE_VM_INTERPRETER_BYTECODE_HPP
  26 #define SHARE_VM_INTERPRETER_BYTECODE_HPP
  27 
  28 #include "interpreter/bytecodes.hpp"
  29 #include "memory/allocation.hpp"
  30 #include "oops/method.hpp"
  31 #include "utilities/align.hpp"
  32 #include "utilities/bytes.hpp"
  33 
  34 class ciBytecodeStream;
  35 
  36 // The base class for different kinds of bytecode abstractions.
  37 // Provides the primitive operations to manipulate code relative
  38 // to the bcp.
  39 
  40 class Bytecode: public StackObj {
  41  protected:
  42   const address   _bcp;
  43   const Bytecodes::Code _code;
  44 
  45   // Address computation
  46   address addr_at            (int offset)        const     { return (address)_bcp + offset; }
  47   u_char byte_at(int offset) const               { return *addr_at(offset); }
  48   address aligned_addr_at    (int offset)        const     { return align_up(addr_at(offset), jintSize); }
  49 
  50   // Word access:
  51   int     get_Java_u2_at     (int offset)        const     { return Bytes::get_Java_u2(addr_at(offset)); }
  52   int     get_Java_u4_at     (int offset)        const     { return Bytes::get_Java_u4(addr_at(offset)); }
  53   int     get_aligned_Java_u4_at(int offset)     const     { return Bytes::get_Java_u4(aligned_addr_at(offset)); }
  54   int     get_native_u2_at   (int offset)        const     { return Bytes::get_native_u2(addr_at(offset)); }
  55   int     get_native_u4_at   (int offset)        const     { return Bytes::get_native_u4(addr_at(offset)); }
  56 
  57  public:
  58   Bytecode(Method* method, address bcp): _bcp(bcp), _code(Bytecodes::code_at(method, addr_at(0))) {
  59     assert(method != NULL, "this form requires a valid Method*");
  60   }
  61   // Defined in ciStreams.hpp
  62   inline Bytecode(const ciBytecodeStream* stream, address bcp = NULL);
  63 
  64   // Attributes
  65   address bcp() const                            { return _bcp; }
  66   int instruction_size() const                   { return Bytecodes::length_for_code_at(_code, bcp()); }
  67 
  68   Bytecodes::Code code() const                   { return _code; }
  69   Bytecodes::Code java_code() const              { return Bytecodes::java_code(code()); }
  70   Bytecodes::Code invoke_code() const            { return (code() == Bytecodes::_invokehandle) ? code() : java_code(); }
  71 
  72   // Static functions for parsing bytecodes in place.
  73   int get_index_u1(Bytecodes::Code bc) const {
  74     assert_same_format_as(bc); assert_index_size(1, bc);
  75     return *(jubyte*)addr_at(1);
  76   }
  77   int get_index_u2(Bytecodes::Code bc, bool is_wide = false) const {
  78     assert_same_format_as(bc, is_wide); assert_index_size(2, bc, is_wide);
  79     address p = addr_at(is_wide ? 2 : 1);
  80     if (can_use_native_byte_order(bc, is_wide))
  81       return Bytes::get_native_u2(p);
  82     else  return Bytes::get_Java_u2(p);
  83   }
  84   int get_index_u1_cpcache(Bytecodes::Code bc) const {
  85     assert_same_format_as(bc); assert_index_size(1, bc);
  86     return *(jubyte*)addr_at(1) + ConstantPool::CPCACHE_INDEX_TAG;
  87   }
  88   int get_index_u2_cpcache(Bytecodes::Code bc) const {
  89     assert_same_format_as(bc); assert_index_size(2, bc); assert_native_index(bc);
  90     return Bytes::get_native_u2(addr_at(1)) + ConstantPool::CPCACHE_INDEX_TAG;
  91   }
  92   int get_index_u4(Bytecodes::Code bc) const {
  93     assert_same_format_as(bc); assert_index_size(4, bc);
  94     assert(can_use_native_byte_order(bc), "");
  95     return Bytes::get_native_u4(addr_at(1));
  96   }
  97   bool has_index_u4(Bytecodes::Code bc) const {
  98     return bc == Bytecodes::_invokedynamic;
  99   }
 100 
 101   int get_offset_s2(Bytecodes::Code bc) const {
 102     assert_same_format_as(bc); assert_offset_size(2, bc);
 103     return (jshort) Bytes::get_Java_u2(addr_at(1));
 104   }
 105   int get_offset_s4(Bytecodes::Code bc) const {
 106     assert_same_format_as(bc); assert_offset_size(4, bc);
 107     return (jint) Bytes::get_Java_u4(addr_at(1));
 108   }
 109 
 110   int get_constant_u1(int offset, Bytecodes::Code bc) const {
 111     assert_same_format_as(bc); assert_constant_size(1, offset, bc);
 112     return *(jbyte*)addr_at(offset);
 113   }
 114   int get_constant_u2(int offset, Bytecodes::Code bc, bool is_wide = false) const {
 115     assert_same_format_as(bc, is_wide); assert_constant_size(2, offset, bc, is_wide);
 116     return (jshort) Bytes::get_Java_u2(addr_at(offset));
 117   }
 118 
 119   // These are used locally and also from bytecode streams.
 120   void assert_same_format_as(Bytecodes::Code testbc, bool is_wide = false) const NOT_DEBUG_RETURN;
 121   static void assert_index_size(int required_size, Bytecodes::Code bc, bool is_wide = false) NOT_DEBUG_RETURN;
 122   static void assert_offset_size(int required_size, Bytecodes::Code bc, bool is_wide = false) NOT_DEBUG_RETURN;
 123   static void assert_constant_size(int required_size, int where, Bytecodes::Code bc, bool is_wide = false) NOT_DEBUG_RETURN;
 124   static void assert_native_index(Bytecodes::Code bc, bool is_wide = false) NOT_DEBUG_RETURN;
 125   static bool can_use_native_byte_order(Bytecodes::Code bc, bool is_wide = false) {
 126     return (!Endian::is_Java_byte_ordering_different() || Bytecodes::native_byte_order(bc /*, is_wide*/));
 127   }
 128 };
 129 
 130 
 131 // Abstractions for lookupswitch bytecode
 132 class LookupswitchPair {
 133  private:
 134   const address _bcp;
 135 
 136   address addr_at            (int offset)        const     { return _bcp + offset; }
 137   int     get_Java_u4_at     (int offset)        const     { return Bytes::get_Java_u4(addr_at(offset)); }
 138 
 139  public:
 140   LookupswitchPair(address bcp): _bcp(bcp) {}
 141   int  match() const                             { return get_Java_u4_at(0 * jintSize); }
 142   int  offset() const                            { return get_Java_u4_at(1 * jintSize); }
 143 };
 144 
 145 
 146 class Bytecode_lookupswitch: public Bytecode {
 147  public:
 148   Bytecode_lookupswitch(Method* method, address bcp): Bytecode(method, bcp) { verify(); }
 149   // Defined in ciStreams.hpp
 150   inline Bytecode_lookupswitch(const ciBytecodeStream* stream);
 151   void verify() const PRODUCT_RETURN;
 152 
 153   // Attributes
 154   int  default_offset() const                    { return get_aligned_Java_u4_at(1 + 0*jintSize); }
 155   int  number_of_pairs() const                   { return get_aligned_Java_u4_at(1 + 1*jintSize); }
 156   LookupswitchPair pair_at(int i) const          {
 157     assert(0 <= i && i < number_of_pairs(), "pair index out of bounds");
 158     return LookupswitchPair(aligned_addr_at(1 + (1 + i)*2*jintSize));
 159   }
 160 };
 161 
 162 class Bytecode_tableswitch: public Bytecode {
 163  public:
 164   Bytecode_tableswitch(Method* method, address bcp): Bytecode(method, bcp) { verify(); }
 165   // Defined in ciStreams.hpp
 166   inline Bytecode_tableswitch(const ciBytecodeStream* stream);
 167   void verify() const PRODUCT_RETURN;
 168 
 169   // Attributes
 170   int  default_offset() const                    { return get_aligned_Java_u4_at(1 + 0*jintSize); }
 171   int  low_key() const                           { return get_aligned_Java_u4_at(1 + 1*jintSize); }
 172   int  high_key() const                          { return get_aligned_Java_u4_at(1 + 2*jintSize); }
 173   int  dest_offset_at(int i) const;
 174   int  length()                                  { return high_key()-low_key()+1; }
 175 };
 176 
 177 // Common code for decoding invokes and field references.
 178 
 179 class Bytecode_member_ref: public Bytecode {
 180  protected:
 181   const Method* _method;                          // method containing the bytecode
 182 
 183   Bytecode_member_ref(const methodHandle& method, int bci)  : Bytecode(method(), method()->bcp_from(bci)), _method(method()) {}
 184 
 185   const Method* method() const                 { return _method; }
 186   ConstantPool* constants() const              { return _method->constants(); }
 187   ConstantPoolCache* cpcache() const           { return _method->constants()->cache(); }
 188   ConstantPoolCacheEntry* cpcache_entry() const;
 189 
 190  public:
 191   int          index() const;                    // cache index (loaded from instruction)
 192   int          pool_index() const;               // constant pool index
 193   Symbol*      klass() const;                    // returns the klass of the method or field
 194   Symbol*      name() const;                     // returns the name of the method or field
 195   Symbol*      signature() const;                // returns the signature of the method or field
 196 
 197   BasicType    result_type() const;              // returns the result type of the getfield or invoke
 198 };
 199 
 200 // Abstraction for invoke_{virtual, static, interface, special, dynamic, handle}
 201 
 202 class Bytecode_invoke: public Bytecode_member_ref {
 203  protected:
 204   // Constructor that skips verification
 205   Bytecode_invoke(const methodHandle& method, int bci, bool unused)  : Bytecode_member_ref(method, bci) {}
 206 
 207  public:
 208   Bytecode_invoke(const methodHandle& method, int bci)  : Bytecode_member_ref(method, bci) { verify(); }
 209   void verify() const;
 210 
 211   // Attributes
 212   methodHandle static_target(TRAPS);             // "specified" method   (from constant pool)
 213   Handle       appendix(TRAPS);                  // if CPCE::has_appendix (from constant pool)
 214 
 215   // Testers
 216   bool is_invokeinterface() const                { return invoke_code() == Bytecodes::_invokeinterface; }
 217   bool is_invokevirtual() const                  { return invoke_code() == Bytecodes::_invokevirtual; }
 218   bool is_invokestatic() const                   { return invoke_code() == Bytecodes::_invokestatic; }
 219   bool is_invokespecial() const                  { return invoke_code() == Bytecodes::_invokespecial; }
 220   bool is_invokedynamic() const                  { return invoke_code() == Bytecodes::_invokedynamic; }
 221   bool is_invokehandle() const                   { return invoke_code() == Bytecodes::_invokehandle; }
 222 
 223   bool has_receiver() const                      { return !is_invokestatic() && !is_invokedynamic(); }
 224 
 225   bool is_valid() const                          { return is_invokeinterface() ||
 226                                                           is_invokevirtual()   ||
 227                                                           is_invokestatic()    ||
 228                                                           is_invokespecial()   ||
 229                                                           is_invokedynamic()   ||
 230                                                           is_invokehandle(); }
 231 
 232   bool has_appendix();
 233 
 234   int size_of_parameters() const;
 235 
 236  private:
 237   // Helper to skip verification.   Used is_valid() to check if the result is really an invoke
 238   inline friend Bytecode_invoke Bytecode_invoke_check(const methodHandle& method, int bci);
 239 };
 240 
 241 inline Bytecode_invoke Bytecode_invoke_check(const methodHandle& method, int bci) {
 242   return Bytecode_invoke(method, bci, false);
 243 }
 244 
 245 
 246 // Abstraction for all field accesses (put/get field/static)
 247 class Bytecode_field: public Bytecode_member_ref {
 248  public:
 249   Bytecode_field(const methodHandle& method, int bci)  : Bytecode_member_ref(method, bci) { verify(); }
 250 
 251   // Testers
 252   bool is_getfield() const                       { return java_code() == Bytecodes::_getfield; }
 253   bool is_putfield() const                       { return java_code() == Bytecodes::_putfield; }
 254   bool is_getstatic() const                      { return java_code() == Bytecodes::_getstatic; }
 255   bool is_putstatic() const                      { return java_code() == Bytecodes::_putstatic; }
 256 
 257   bool is_getter() const                         { return is_getfield()  || is_getstatic(); }
 258   bool is_static() const                         { return is_getstatic() || is_putstatic(); }
 259 
 260   bool is_valid() const                          { return is_getfield()   ||
 261                                                           is_putfield()   ||
 262                                                           is_getstatic()  ||
 263                                                           is_putstatic(); }
 264   void verify() const;
 265 };
 266 
 267 // Abstraction for checkcast
 268 class Bytecode_checkcast: public Bytecode {
 269  public:
 270   Bytecode_checkcast(Method* method, address bcp): Bytecode(method, bcp) { verify(); }
 271   void verify() const { assert(Bytecodes::java_code(code()) == Bytecodes::_checkcast, "check checkcast"); }
 272 
 273   // Returns index
 274   long index() const   { return get_index_u2(Bytecodes::_checkcast); };
 275 };
 276 
 277 // Abstraction for instanceof
 278 class Bytecode_instanceof: public Bytecode {
 279  public:
 280   Bytecode_instanceof(Method* method, address bcp): Bytecode(method, bcp) { verify(); }
 281   void verify() const { assert(code() == Bytecodes::_instanceof, "check instanceof"); }
 282 
 283   // Returns index
 284   long index() const   { return get_index_u2(Bytecodes::_instanceof); };
 285 };
 286 
 287 class Bytecode_new: public Bytecode {
 288  public:
 289   Bytecode_new(Method* method, address bcp): Bytecode(method, bcp) { verify(); }
 290   void verify() const { assert(java_code() == Bytecodes::_new, "check new"); }
 291 
 292   // Returns index
 293   long index() const   { return get_index_u2(Bytecodes::_new); };
 294 };
 295 
 296 class Bytecode_multianewarray: public Bytecode {
 297  public:
 298   Bytecode_multianewarray(Method* method, address bcp): Bytecode(method, bcp) { verify(); }
 299   void verify() const { assert(java_code() == Bytecodes::_multianewarray, "check new"); }
 300 
 301   // Returns index
 302   long index() const   { return get_index_u2(Bytecodes::_multianewarray); };
 303 };
 304 
 305 class Bytecode_anewarray: public Bytecode {
 306  public:
 307   Bytecode_anewarray(Method* method, address bcp): Bytecode(method, bcp) { verify(); }
 308   void verify() const { assert(java_code() == Bytecodes::_anewarray, "check anewarray"); }
 309 
 310   // Returns index
 311   long index() const   { return get_index_u2(Bytecodes::_anewarray); };
 312 };
 313 
 314 // Abstraction for ldc, ldc_w and ldc2_w
 315 class Bytecode_loadconstant: public Bytecode {
 316  private:
 317   const Method* _method;
 318 
 319   int raw_index() const;
 320 
 321  public:
 322   Bytecode_loadconstant(const methodHandle& method, int bci): Bytecode(method(), method->bcp_from(bci)), _method(method()) { verify(); }
 323 
 324   void verify() const {
 325     assert(_method != NULL, "must supply method");
 326     Bytecodes::Code stdc = Bytecodes::java_code(code());
 327     assert(stdc == Bytecodes::_ldc ||
 328            stdc == Bytecodes::_ldc_w ||
 329            stdc == Bytecodes::_ldc2_w, "load constant");
 330   }
 331 
 332   // Only non-standard bytecodes (fast_aldc) have reference cache indexes.
 333   bool has_cache_index() const { return code() >= Bytecodes::number_of_java_codes; }
 334 
 335   int pool_index() const;               // index into constant pool
 336   int cache_index() const {             // index into reference cache (or -1 if none)
 337     return has_cache_index() ? raw_index() : -1;
 338   }
 339 
 340   BasicType result_type() const;        // returns the result type of the ldc
 341 
 342   oop resolve_constant(TRAPS) const;
 343 };
 344 
 345 #endif // SHARE_VM_INTERPRETER_BYTECODE_HPP