1 /*
   2  * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 // This file contains the platform-independent parts
  26 // of the abstract interpreter and the abstract interpreter generator.
  27 
  28 // Organization of the interpreter(s). There exists two different interpreters in hotpot
  29 // an assembly language version (aka template interpreter) and a high level language version
  30 // (aka c++ interpreter). Th division of labor is as follows:
  31 
  32 // Template Interpreter          C++ Interpreter        Functionality
  33 //
  34 // templateTable*                bytecodeInterpreter*   actual interpretation of bytecodes
  35 //
  36 // templateInterpreter*          cppInterpreter*        generation of assembly code that creates
  37 //                                                      and manages interpreter runtime frames.
  38 //                                                      Also code for populating interpreter
  39 //                                                      frames created during deoptimization.
  40 //
  41 // For both template and c++ interpreter. There are common files for aspects of the interpreter
  42 // that are generic to both interpreters. This is the layout:
  43 //
  44 // abstractInterpreter.hpp: generic description of the interpreter.
  45 // interpreter*:            generic frame creation and handling.
  46 //
  47 
  48 //------------------------------------------------------------------------------------------------------------------------
  49 // The C++ interface to the bytecode interpreter(s).
  50 
  51 class AbstractInterpreter: AllStatic {
  52   friend class VMStructs;
  53   friend class Interpreter;
  54   friend class CppInterpreterGenerator;
  55  public:
  56   enum MethodKind {
  57     zerolocals,                                                 // method needs locals initialization
  58     zerolocals_synchronized,                                    // method needs locals initialization & is synchronized
  59     native,                                                     // native method
  60     native_synchronized,                                        // native method & is synchronized
  61     empty,                                                      // empty method (code: _return)
  62     accessor,                                                   // accessor method (code: _aload_0, _getfield, _(a|i)return)
  63     abstract,                                                   // abstract method (throws an AbstractMethodException)
  64     method_handle,                                              // java.dyn.MethodHandles::invoke
  65     java_lang_math_sin,                                         // implementation of java.lang.Math.sin   (x)
  66     java_lang_math_cos,                                         // implementation of java.lang.Math.cos   (x)
  67     java_lang_math_tan,                                         // implementation of java.lang.Math.tan   (x)
  68     java_lang_math_abs,                                         // implementation of java.lang.Math.abs   (x)
  69     java_lang_math_sqrt,                                        // implementation of java.lang.Math.sqrt  (x)
  70     java_lang_math_log,                                         // implementation of java.lang.Math.log   (x)
  71     java_lang_math_log10,                                       // implementation of java.lang.Math.log10 (x)
  72     number_of_method_entries,
  73     invalid = -1
  74   };
  75 
  76   enum SomeConstants {
  77     number_of_result_handlers = 10                              // number of result handlers for native calls
  78   };
  79 
  80  protected:
  81   static StubQueue* _code;                                      // the interpreter code (codelets)
  82 
  83   static bool       _notice_safepoints;                         // true if safepoints are activated
  84 
  85   static address    _native_entry_begin;                        // Region for native entry code
  86   static address    _native_entry_end;
  87 
  88   // method entry points
  89   static address    _entry_table[number_of_method_entries];     // entry points for a given method
  90   static address    _native_abi_to_tosca[number_of_result_handlers];  // for native method result handlers
  91   static address    _slow_signature_handler;                              // the native method generic (slow) signature handler
  92 
  93   static address    _rethrow_exception_entry;                   // rethrows an activation in previous frame
  94 
  95   friend class      AbstractInterpreterGenerator;
  96   friend class              InterpreterGenerator;
  97   friend class      InterpreterMacroAssembler;
  98 
  99  public:
 100   // Initialization/debugging
 101   static void       initialize();
 102   static StubQueue* code()                                      { return _code; }
 103 
 104 
 105   // Method activation
 106   static MethodKind method_kind(methodHandle m);
 107   static address    entry_for_kind(MethodKind k)                { assert(0 <= k && k < number_of_method_entries, "illegal kind"); return _entry_table[k]; }
 108   static address    entry_for_method(methodHandle m)            { return _entry_table[method_kind(m)]; }
 109 
 110   static void       print_method_kind(MethodKind kind)          PRODUCT_RETURN;
 111 
 112   // Runtime support
 113 
 114   // length = invoke bytecode length (to advance to next bytecode)
 115   static address    deopt_entry   (TosState state, int length) { ShouldNotReachHere(); return NULL; }
 116   static address    return_entry  (TosState state, int length) { ShouldNotReachHere(); return NULL; }
 117 
 118   static address    rethrow_exception_entry()                   { return _rethrow_exception_entry; }
 119 
 120   // Activation size in words for a method that is just being called.
 121   // Parameters haven't been pushed so count them too.
 122   static int        size_top_interpreter_activation(methodOop method);
 123 
 124   // Deoptimization support
 125   // Compute the entry address for continuation after
 126   static address deopt_continue_after_entry(methodOop method,
 127                                             address bcp,
 128                                             int callee_parameters,
 129                                             bool is_top_frame);
 130   // Compute the entry address for reexecution
 131   static address deopt_reexecute_entry(methodOop method, address bcp);
 132   // Deoptimization should reexecute this bytecode
 133   static bool    bytecode_should_reexecute(Bytecodes::Code code);
 134 
 135   // share implementation of size_activation and layout_activation:
 136   static int        size_activation(methodOop method,
 137                                     int temps,
 138                                     int popframe_args,
 139                                     int monitors,
 140                                     int callee_params,
 141                                     int callee_locals,
 142                                     bool is_top_frame);
 143 
 144   static int       layout_activation(methodOop method,
 145                                       int temps,
 146                                       int popframe_args,
 147                                       int monitors,
 148                                       int callee_params,
 149                                       int callee_locals,
 150                                       frame* caller,
 151                                       frame* interpreter_frame,
 152                                       bool is_top_frame);
 153 
 154   // Runtime support
 155   static bool       is_not_reached(                       methodHandle method, int bci);
 156   // Safepoint support
 157   static void       notice_safepoints()                         { ShouldNotReachHere(); } // stops the thread when reaching a safepoint
 158   static void       ignore_safepoints()                         { ShouldNotReachHere(); } // ignores safepoints
 159 
 160   // Support for native calls
 161   static address    slow_signature_handler()                    { return _slow_signature_handler; }
 162   static address    result_handler(BasicType type)              { return _native_abi_to_tosca[BasicType_as_index(type)]; }
 163   static int        BasicType_as_index(BasicType type);         // computes index into result_handler_by_index table
 164   static bool       in_native_entry(address pc)                 { return _native_entry_begin <= pc && pc < _native_entry_end; }
 165   // Debugging/printing
 166   static void       print();                                    // prints the interpreter code
 167 
 168   // Support for Tagged Stacks
 169   //
 170   // Tags are stored on the Java Expression stack above the value:
 171   //
 172   //  tag
 173   //  value
 174   //
 175   // For double values:
 176   //
 177   //  tag2
 178   //  high word
 179   //  tag1
 180   //  low word
 181 
 182  public:
 183   static int stackElementWords()   { return TaggedStackInterpreter ? 2 : 1; }
 184   static int stackElementSize()    { return stackElementWords()*wordSize; }
 185   static int logStackElementSize() { return
 186                  TaggedStackInterpreter? LogBytesPerWord+1 : LogBytesPerWord; }
 187 
 188   // Tag is at pointer, value is one below for a stack growing down
 189   // (or above for stack growing up)
 190   static int  value_offset_in_bytes()  {
 191     return TaggedStackInterpreter ?
 192       frame::interpreter_frame_expression_stack_direction() * wordSize : 0;
 193   }
 194   static int  tag_offset_in_bytes()    {
 195     assert(TaggedStackInterpreter, "should not call this");
 196     return 0;
 197   }
 198 
 199   // Tagged Locals
 200   // Locals are stored relative to Llocals:
 201   //
 202   // tag    <- Llocals[n]
 203   // value
 204   //
 205   // Category 2 types are indexed as:
 206   //
 207   // tag    <- Llocals[-n]
 208   // high word
 209   // tag    <- Llocals[-n+1]
 210   // low word
 211   //
 212 
 213   // Local values relative to locals[n]
 214   static int  local_offset_in_bytes(int n) {
 215     return ((frame::interpreter_frame_expression_stack_direction() * n) *
 216             stackElementSize()) + value_offset_in_bytes();
 217   }
 218   static int  local_tag_offset_in_bytes(int n) {
 219     assert(TaggedStackInterpreter, "should not call this");
 220     return ((frame::interpreter_frame_expression_stack_direction() * n) *
 221             stackElementSize()) + tag_offset_in_bytes();
 222   }
 223 
 224   // access to stacked values according to type:
 225   static oop* oop_addr_in_slot(intptr_t* slot_addr) {
 226     return (oop*) slot_addr;
 227   }
 228   static jint* int_addr_in_slot(intptr_t* slot_addr) {
 229     if ((int) sizeof(jint) < wordSize && !Bytes::is_Java_byte_ordering_different())
 230       // big-endian LP64
 231       return (jint*)(slot_addr + 1) - 1;
 232     else
 233       return (jint*) slot_addr;
 234   }
 235   static jlong long_in_slot(intptr_t* slot_addr) {
 236     if (sizeof(intptr_t) >= sizeof(jlong)) {
 237       return *(jlong*) slot_addr;
 238     } else if (!TaggedStackInterpreter) {
 239       return Bytes::get_native_u8((address)slot_addr);
 240     } else {
 241       assert(sizeof(intptr_t) * 2 == sizeof(jlong), "ILP32");
 242       // assemble the long in memory order (not arithmetic order)
 243       union { jlong j; jint i[2]; } u;
 244       u.i[0] = (jint) slot_addr[0*stackElementSize()];
 245       u.i[1] = (jint) slot_addr[1*stackElementSize()];
 246       return u.j;
 247     }
 248   }
 249   static void set_long_in_slot(intptr_t* slot_addr, jlong value) {
 250     if (sizeof(intptr_t) >= sizeof(jlong)) {
 251       *(jlong*) slot_addr = value;
 252     } else if (!TaggedStackInterpreter) {
 253       Bytes::put_native_u8((address)slot_addr, value);
 254     } else {
 255       assert(sizeof(intptr_t) * 2 == sizeof(jlong), "ILP32");
 256       // assemble the long in memory order (not arithmetic order)
 257       union { jlong j; jint i[2]; } u;
 258       u.j = value;
 259       slot_addr[0*stackElementSize()] = (intptr_t) u.i[0];
 260       slot_addr[1*stackElementSize()] = (intptr_t) u.i[1];
 261     }
 262   }
 263   static void get_jvalue_in_slot(intptr_t* slot_addr, BasicType type, jvalue* value) {
 264     switch (type) {
 265     case T_BOOLEAN: value->z = *int_addr_in_slot(slot_addr);            break;
 266     case T_CHAR:    value->c = *int_addr_in_slot(slot_addr);            break;
 267     case T_BYTE:    value->b = *int_addr_in_slot(slot_addr);            break;
 268     case T_SHORT:   value->s = *int_addr_in_slot(slot_addr);            break;
 269     case T_INT:     value->i = *int_addr_in_slot(slot_addr);            break;
 270     case T_LONG:    value->j = long_in_slot(slot_addr);                 break;
 271     case T_FLOAT:   value->f = *(jfloat*)int_addr_in_slot(slot_addr);   break;
 272     case T_DOUBLE:  value->d = jdouble_cast(long_in_slot(slot_addr));   break;
 273     case T_OBJECT:  value->l = (jobject)*oop_addr_in_slot(slot_addr);   break;
 274     default:        ShouldNotReachHere();
 275     }
 276   }
 277   static void set_jvalue_in_slot(intptr_t* slot_addr, BasicType type, jvalue* value) {
 278     switch (type) {
 279     case T_BOOLEAN: *int_addr_in_slot(slot_addr) = (value->z != 0);     break;
 280     case T_CHAR:    *int_addr_in_slot(slot_addr) = value->c;            break;
 281     case T_BYTE:    *int_addr_in_slot(slot_addr) = value->b;            break;
 282     case T_SHORT:   *int_addr_in_slot(slot_addr) = value->s;            break;
 283     case T_INT:     *int_addr_in_slot(slot_addr) = value->i;            break;
 284     case T_LONG:    set_long_in_slot(slot_addr, value->j);              break;
 285     case T_FLOAT:   *(jfloat*)int_addr_in_slot(slot_addr) = value->f;   break;
 286     case T_DOUBLE:  set_long_in_slot(slot_addr, jlong_cast(value->d));  break;
 287     case T_OBJECT:  *oop_addr_in_slot(slot_addr) = (oop) value->l;      break;
 288     default:        ShouldNotReachHere();
 289     }
 290   }
 291 };
 292 
 293 //------------------------------------------------------------------------------------------------------------------------
 294 // The interpreter generator.
 295 
 296 class Template;
 297 class AbstractInterpreterGenerator: public StackObj {
 298  protected:
 299   InterpreterMacroAssembler* _masm;
 300 
 301   // shared code sequences
 302   // Converter for native abi result to tosca result
 303   address generate_result_handler_for(BasicType type);
 304   address generate_slow_signature_handler();
 305 
 306   // entry point generator
 307   address generate_method_entry(AbstractInterpreter::MethodKind kind);
 308 
 309   void bang_stack_shadow_pages(bool native_call);
 310 
 311   void generate_all();
 312 
 313  public:
 314   AbstractInterpreterGenerator(StubQueue* _code);
 315 };