1 /*
   2  * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2015, 2016 SAP SE. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "asm/macroAssembler.inline.hpp"
  28 #include "interpreter/bytecodeHistogram.hpp"
  29 #include "interpreter/interpreter.hpp"
  30 #include "interpreter/interpreterRuntime.hpp"
  31 #include "interpreter/interp_masm.hpp"
  32 #include "interpreter/templateInterpreterGenerator.hpp"
  33 #include "interpreter/templateTable.hpp"
  34 #include "oops/arrayOop.hpp"
  35 #include "oops/methodData.hpp"
  36 #include "oops/method.hpp"
  37 #include "oops/oop.inline.hpp"
  38 #include "prims/jvmtiExport.hpp"
  39 #include "prims/jvmtiThreadState.hpp"
  40 #include "runtime/arguments.hpp"
  41 #include "runtime/deoptimization.hpp"
  42 #include "runtime/frame.inline.hpp"
  43 #include "runtime/sharedRuntime.hpp"
  44 #include "runtime/stubRoutines.hpp"
  45 #include "runtime/synchronizer.hpp"
  46 #include "runtime/timer.hpp"
  47 #include "runtime/vframeArray.hpp"
  48 #include "utilities/debug.hpp"
  49 #include "utilities/macros.hpp"
  50 
  51 #undef __
  52 #define __ _masm->
  53 
  54 // Size of interpreter code.  Increase if too small.  Interpreter will
  55 // fail with a guarantee ("not enough space for interpreter generation");
  56 // if too small.
  57 // Run with +PrintInterpreter to get the VM to print out the size.
  58 // Max size with JVMTI
  59 int TemplateInterpreter::InterpreterCodeSize = 230*K;
  60 
  61 #ifdef PRODUCT
  62 #define BLOCK_COMMENT(str) /* nothing */
  63 #else
  64 #define BLOCK_COMMENT(str) __ block_comment(str)
  65 #endif
  66 
  67 #define BIND(label)        __ bind(label); BLOCK_COMMENT(#label ":")
  68 
  69 //-----------------------------------------------------------------------------
  70 
  71 address TemplateInterpreterGenerator::generate_slow_signature_handler() {
  72   // Slow_signature handler that respects the PPC C calling conventions.
  73   //
  74   // We get called by the native entry code with our output register
  75   // area == 8. First we call InterpreterRuntime::get_result_handler
  76   // to copy the pointer to the signature string temporarily to the
  77   // first C-argument and to return the result_handler in
  78   // R3_RET. Since native_entry will copy the jni-pointer to the
  79   // first C-argument slot later on, it is OK to occupy this slot
  80   // temporarilly. Then we copy the argument list on the java
  81   // expression stack into native varargs format on the native stack
  82   // and load arguments into argument registers. Integer arguments in
  83   // the varargs vector will be sign-extended to 8 bytes.
  84   //
  85   // On entry:
  86   //   R3_ARG1        - intptr_t*     Address of java argument list in memory.
  87   //   R15_prev_state - BytecodeInterpreter* Address of interpreter state for
  88   //     this method
  89   //   R19_method
  90   //
  91   // On exit (just before return instruction):
  92   //   R3_RET            - contains the address of the result_handler.
  93   //   R4_ARG2           - is not updated for static methods and contains "this" otherwise.
  94   //   R5_ARG3-R10_ARG8: - When the (i-2)th Java argument is not of type float or double,
  95   //                       ARGi contains this argument. Otherwise, ARGi is not updated.
  96   //   F1_ARG1-F13_ARG13 - contain the first 13 arguments of type float or double.
  97 
  98   const int LogSizeOfTwoInstructions = 3;
  99 
 100   // FIXME: use Argument:: GL: Argument names different numbers!
 101   const int max_fp_register_arguments  = 13;
 102   const int max_int_register_arguments = 6;  // first 2 are reserved
 103 
 104   const Register arg_java       = R21_tmp1;
 105   const Register arg_c          = R22_tmp2;
 106   const Register signature      = R23_tmp3;  // is string
 107   const Register sig_byte       = R24_tmp4;
 108   const Register fpcnt          = R25_tmp5;
 109   const Register argcnt         = R26_tmp6;
 110   const Register intSlot        = R27_tmp7;
 111   const Register target_sp      = R28_tmp8;
 112   const FloatRegister floatSlot = F0;
 113 
 114   address entry = __ function_entry();
 115 
 116   __ save_LR_CR(R0);
 117   __ save_nonvolatile_gprs(R1_SP, _spill_nonvolatiles_neg(r14));
 118   // We use target_sp for storing arguments in the C frame.
 119   __ mr(target_sp, R1_SP);
 120   __ push_frame_reg_args_nonvolatiles(0, R11_scratch1);
 121 
 122   __ mr(arg_java, R3_ARG1);
 123 
 124   __ call_VM_leaf(CAST_FROM_FN_PTR(address, InterpreterRuntime::get_signature), R16_thread, R19_method);
 125 
 126   // Signature is in R3_RET. Signature is callee saved.
 127   __ mr(signature, R3_RET);
 128 
 129   // Get the result handler.
 130   __ call_VM_leaf(CAST_FROM_FN_PTR(address, InterpreterRuntime::get_result_handler), R16_thread, R19_method);
 131 
 132   {
 133     Label L;
 134     // test if static
 135     // _access_flags._flags must be at offset 0.
 136     // TODO PPC port: requires change in shared code.
 137     //assert(in_bytes(AccessFlags::flags_offset()) == 0,
 138     //       "MethodDesc._access_flags == MethodDesc._access_flags._flags");
 139     // _access_flags must be a 32 bit value.
 140     assert(sizeof(AccessFlags) == 4, "wrong size");
 141     __ lwa(R11_scratch1/*access_flags*/, method_(access_flags));
 142     // testbit with condition register.
 143     __ testbitdi(CCR0, R0, R11_scratch1/*access_flags*/, JVM_ACC_STATIC_BIT);
 144     __ btrue(CCR0, L);
 145     // For non-static functions, pass "this" in R4_ARG2 and copy it
 146     // to 2nd C-arg slot.
 147     // We need to box the Java object here, so we use arg_java
 148     // (address of current Java stack slot) as argument and don't
 149     // dereference it as in case of ints, floats, etc.
 150     __ mr(R4_ARG2, arg_java);
 151     __ addi(arg_java, arg_java, -BytesPerWord);
 152     __ std(R4_ARG2, _abi(carg_2), target_sp);
 153     __ bind(L);
 154   }
 155 
 156   // Will be incremented directly after loop_start. argcnt=0
 157   // corresponds to 3rd C argument.
 158   __ li(argcnt, -1);
 159   // arg_c points to 3rd C argument
 160   __ addi(arg_c, target_sp, _abi(carg_3));
 161   // no floating-point args parsed so far
 162   __ li(fpcnt, 0);
 163 
 164   Label move_intSlot_to_ARG, move_floatSlot_to_FARG;
 165   Label loop_start, loop_end;
 166   Label do_int, do_long, do_float, do_double, do_dontreachhere, do_object, do_array, do_boxed;
 167 
 168   // signature points to '(' at entry
 169 #ifdef ASSERT
 170   __ lbz(sig_byte, 0, signature);
 171   __ cmplwi(CCR0, sig_byte, '(');
 172   __ bne(CCR0, do_dontreachhere);
 173 #endif
 174 
 175   __ bind(loop_start);
 176 
 177   __ addi(argcnt, argcnt, 1);
 178   __ lbzu(sig_byte, 1, signature);
 179 
 180   __ cmplwi(CCR0, sig_byte, ')'); // end of signature
 181   __ beq(CCR0, loop_end);
 182 
 183   __ cmplwi(CCR0, sig_byte, 'B'); // byte
 184   __ beq(CCR0, do_int);
 185 
 186   __ cmplwi(CCR0, sig_byte, 'C'); // char
 187   __ beq(CCR0, do_int);
 188 
 189   __ cmplwi(CCR0, sig_byte, 'D'); // double
 190   __ beq(CCR0, do_double);
 191 
 192   __ cmplwi(CCR0, sig_byte, 'F'); // float
 193   __ beq(CCR0, do_float);
 194 
 195   __ cmplwi(CCR0, sig_byte, 'I'); // int
 196   __ beq(CCR0, do_int);
 197 
 198   __ cmplwi(CCR0, sig_byte, 'J'); // long
 199   __ beq(CCR0, do_long);
 200 
 201   __ cmplwi(CCR0, sig_byte, 'S'); // short
 202   __ beq(CCR0, do_int);
 203 
 204   __ cmplwi(CCR0, sig_byte, 'Z'); // boolean
 205   __ beq(CCR0, do_int);
 206 
 207   __ cmplwi(CCR0, sig_byte, 'L'); // object
 208   __ beq(CCR0, do_object);
 209 
 210   __ cmplwi(CCR0, sig_byte, '['); // array
 211   __ beq(CCR0, do_array);
 212 
 213   //  __ cmplwi(CCR0, sig_byte, 'V'); // void cannot appear since we do not parse the return type
 214   //  __ beq(CCR0, do_void);
 215 
 216   __ bind(do_dontreachhere);
 217 
 218   __ unimplemented("ShouldNotReachHere in slow_signature_handler", 120);
 219 
 220   __ bind(do_array);
 221 
 222   {
 223     Label start_skip, end_skip;
 224 
 225     __ bind(start_skip);
 226     __ lbzu(sig_byte, 1, signature);
 227     __ cmplwi(CCR0, sig_byte, '[');
 228     __ beq(CCR0, start_skip); // skip further brackets
 229     __ cmplwi(CCR0, sig_byte, '9');
 230     __ bgt(CCR0, end_skip);   // no optional size
 231     __ cmplwi(CCR0, sig_byte, '0');
 232     __ bge(CCR0, start_skip); // skip optional size
 233     __ bind(end_skip);
 234 
 235     __ cmplwi(CCR0, sig_byte, 'L');
 236     __ beq(CCR0, do_object);  // for arrays of objects, the name of the object must be skipped
 237     __ b(do_boxed);          // otherwise, go directly to do_boxed
 238   }
 239 
 240   __ bind(do_object);
 241   {
 242     Label L;
 243     __ bind(L);
 244     __ lbzu(sig_byte, 1, signature);
 245     __ cmplwi(CCR0, sig_byte, ';');
 246     __ bne(CCR0, L);
 247    }
 248   // Need to box the Java object here, so we use arg_java (address of
 249   // current Java stack slot) as argument and don't dereference it as
 250   // in case of ints, floats, etc.
 251   Label do_null;
 252   __ bind(do_boxed);
 253   __ ld(R0,0, arg_java);
 254   __ cmpdi(CCR0, R0, 0);
 255   __ li(intSlot,0);
 256   __ beq(CCR0, do_null);
 257   __ mr(intSlot, arg_java);
 258   __ bind(do_null);
 259   __ std(intSlot, 0, arg_c);
 260   __ addi(arg_java, arg_java, -BytesPerWord);
 261   __ addi(arg_c, arg_c, BytesPerWord);
 262   __ cmplwi(CCR0, argcnt, max_int_register_arguments);
 263   __ blt(CCR0, move_intSlot_to_ARG);
 264   __ b(loop_start);
 265 
 266   __ bind(do_int);
 267   __ lwa(intSlot, 0, arg_java);
 268   __ std(intSlot, 0, arg_c);
 269   __ addi(arg_java, arg_java, -BytesPerWord);
 270   __ addi(arg_c, arg_c, BytesPerWord);
 271   __ cmplwi(CCR0, argcnt, max_int_register_arguments);
 272   __ blt(CCR0, move_intSlot_to_ARG);
 273   __ b(loop_start);
 274 
 275   __ bind(do_long);
 276   __ ld(intSlot, -BytesPerWord, arg_java);
 277   __ std(intSlot, 0, arg_c);
 278   __ addi(arg_java, arg_java, - 2 * BytesPerWord);
 279   __ addi(arg_c, arg_c, BytesPerWord);
 280   __ cmplwi(CCR0, argcnt, max_int_register_arguments);
 281   __ blt(CCR0, move_intSlot_to_ARG);
 282   __ b(loop_start);
 283 
 284   __ bind(do_float);
 285   __ lfs(floatSlot, 0, arg_java);
 286 #if defined(LINUX)
 287   // Linux uses ELF ABI. Both original ELF and ELFv2 ABIs have float
 288   // in the least significant word of an argument slot.
 289 #if defined(VM_LITTLE_ENDIAN)
 290   __ stfs(floatSlot, 0, arg_c);
 291 #else
 292   __ stfs(floatSlot, 4, arg_c);
 293 #endif
 294 #elif defined(AIX)
 295   // Although AIX runs on big endian CPU, float is in most significant
 296   // word of an argument slot.
 297   __ stfs(floatSlot, 0, arg_c);
 298 #else
 299 #error "unknown OS"
 300 #endif
 301   __ addi(arg_java, arg_java, -BytesPerWord);
 302   __ addi(arg_c, arg_c, BytesPerWord);
 303   __ cmplwi(CCR0, fpcnt, max_fp_register_arguments);
 304   __ blt(CCR0, move_floatSlot_to_FARG);
 305   __ b(loop_start);
 306 
 307   __ bind(do_double);
 308   __ lfd(floatSlot, - BytesPerWord, arg_java);
 309   __ stfd(floatSlot, 0, arg_c);
 310   __ addi(arg_java, arg_java, - 2 * BytesPerWord);
 311   __ addi(arg_c, arg_c, BytesPerWord);
 312   __ cmplwi(CCR0, fpcnt, max_fp_register_arguments);
 313   __ blt(CCR0, move_floatSlot_to_FARG);
 314   __ b(loop_start);
 315 
 316   __ bind(loop_end);
 317 
 318   __ pop_frame();
 319   __ restore_nonvolatile_gprs(R1_SP, _spill_nonvolatiles_neg(r14));
 320   __ restore_LR_CR(R0);
 321 
 322   __ blr();
 323 
 324   Label move_int_arg, move_float_arg;
 325   __ bind(move_int_arg); // each case must consist of 2 instructions (otherwise adapt LogSizeOfTwoInstructions)
 326   __ mr(R5_ARG3, intSlot);  __ b(loop_start);
 327   __ mr(R6_ARG4, intSlot);  __ b(loop_start);
 328   __ mr(R7_ARG5, intSlot);  __ b(loop_start);
 329   __ mr(R8_ARG6, intSlot);  __ b(loop_start);
 330   __ mr(R9_ARG7, intSlot);  __ b(loop_start);
 331   __ mr(R10_ARG8, intSlot); __ b(loop_start);
 332 
 333   __ bind(move_float_arg); // each case must consist of 2 instructions (otherwise adapt LogSizeOfTwoInstructions)
 334   __ fmr(F1_ARG1, floatSlot);   __ b(loop_start);
 335   __ fmr(F2_ARG2, floatSlot);   __ b(loop_start);
 336   __ fmr(F3_ARG3, floatSlot);   __ b(loop_start);
 337   __ fmr(F4_ARG4, floatSlot);   __ b(loop_start);
 338   __ fmr(F5_ARG5, floatSlot);   __ b(loop_start);
 339   __ fmr(F6_ARG6, floatSlot);   __ b(loop_start);
 340   __ fmr(F7_ARG7, floatSlot);   __ b(loop_start);
 341   __ fmr(F8_ARG8, floatSlot);   __ b(loop_start);
 342   __ fmr(F9_ARG9, floatSlot);   __ b(loop_start);
 343   __ fmr(F10_ARG10, floatSlot); __ b(loop_start);
 344   __ fmr(F11_ARG11, floatSlot); __ b(loop_start);
 345   __ fmr(F12_ARG12, floatSlot); __ b(loop_start);
 346   __ fmr(F13_ARG13, floatSlot); __ b(loop_start);
 347 
 348   __ bind(move_intSlot_to_ARG);
 349   __ sldi(R0, argcnt, LogSizeOfTwoInstructions);
 350   __ load_const(R11_scratch1, move_int_arg); // Label must be bound here.
 351   __ add(R11_scratch1, R0, R11_scratch1);
 352   __ mtctr(R11_scratch1/*branch_target*/);
 353   __ bctr();
 354   __ bind(move_floatSlot_to_FARG);
 355   __ sldi(R0, fpcnt, LogSizeOfTwoInstructions);
 356   __ addi(fpcnt, fpcnt, 1);
 357   __ load_const(R11_scratch1, move_float_arg); // Label must be bound here.
 358   __ add(R11_scratch1, R0, R11_scratch1);
 359   __ mtctr(R11_scratch1/*branch_target*/);
 360   __ bctr();
 361 
 362   return entry;
 363 }
 364 
 365 address TemplateInterpreterGenerator::generate_result_handler_for(BasicType type) {
 366   //
 367   // Registers alive
 368   //   R3_RET
 369   //   LR
 370   //
 371   // Registers updated
 372   //   R3_RET
 373   //
 374 
 375   Label done;
 376   address entry = __ pc();
 377 
 378   switch (type) {
 379   case T_BOOLEAN:
 380     // convert !=0 to 1
 381     __ neg(R0, R3_RET);
 382     __ orr(R0, R3_RET, R0);
 383     __ srwi(R3_RET, R0, 31);
 384     break;
 385   case T_BYTE:
 386      // sign extend 8 bits
 387      __ extsb(R3_RET, R3_RET);
 388      break;
 389   case T_CHAR:
 390      // zero extend 16 bits
 391      __ clrldi(R3_RET, R3_RET, 48);
 392      break;
 393   case T_SHORT:
 394      // sign extend 16 bits
 395      __ extsh(R3_RET, R3_RET);
 396      break;
 397   case T_INT:
 398      // sign extend 32 bits
 399      __ extsw(R3_RET, R3_RET);
 400      break;
 401   case T_LONG:
 402      break;
 403   case T_OBJECT:
 404     // unbox result if not null
 405     __ cmpdi(CCR0, R3_RET, 0);
 406     __ beq(CCR0, done);
 407     __ ld(R3_RET, 0, R3_RET);
 408     __ verify_oop(R3_RET);
 409     break;
 410   case T_FLOAT:
 411      break;
 412   case T_DOUBLE:
 413      break;
 414   case T_VOID:
 415      break;
 416   default: ShouldNotReachHere();
 417   }
 418 
 419   BIND(done);
 420   __ blr();
 421 
 422   return entry;
 423 }
 424 
 425 // Abstract method entry.
 426 //
 427 address TemplateInterpreterGenerator::generate_abstract_entry(void) {
 428   address entry = __ pc();
 429 
 430   //
 431   // Registers alive
 432   //   R16_thread     - JavaThread*
 433   //   R19_method     - callee's method (method to be invoked)
 434   //   R1_SP          - SP prepared such that caller's outgoing args are near top
 435   //   LR             - return address to caller
 436   //
 437   // Stack layout at this point:
 438   //
 439   //   0       [TOP_IJAVA_FRAME_ABI]         <-- R1_SP
 440   //           alignment (optional)
 441   //           [outgoing Java arguments]
 442   //           ...
 443   //   PARENT  [PARENT_IJAVA_FRAME_ABI]
 444   //            ...
 445   //
 446 
 447   // Can't use call_VM here because we have not set up a new
 448   // interpreter state. Make the call to the vm and make it look like
 449   // our caller set up the JavaFrameAnchor.
 450   __ set_top_ijava_frame_at_SP_as_last_Java_frame(R1_SP, R12_scratch2/*tmp*/);
 451 
 452   // Push a new C frame and save LR.
 453   __ save_LR_CR(R0);
 454   __ push_frame_reg_args(0, R11_scratch1);
 455 
 456   // This is not a leaf but we have a JavaFrameAnchor now and we will
 457   // check (create) exceptions afterward so this is ok.
 458   __ call_VM_leaf(CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_AbstractMethodError),
 459                   R16_thread);
 460 
 461   // Pop the C frame and restore LR.
 462   __ pop_frame();
 463   __ restore_LR_CR(R0);
 464 
 465   // Reset JavaFrameAnchor from call_VM_leaf above.
 466   __ reset_last_Java_frame();
 467 
 468   // We don't know our caller, so jump to the general forward exception stub,
 469   // which will also pop our full frame off. Satisfy the interface of
 470   // SharedRuntime::generate_forward_exception()
 471   __ load_const_optimized(R11_scratch1, StubRoutines::forward_exception_entry(), R0);
 472   __ mtctr(R11_scratch1);
 473   __ bctr();
 474 
 475   return entry;
 476 }
 477 
 478 // Interpreter intrinsic for WeakReference.get().
 479 // 1. Don't push a full blown frame and go on dispatching, but fetch the value
 480 //    into R8 and return quickly
 481 // 2. If G1 is active we *must* execute this intrinsic for corrrectness:
 482 //    It contains a GC barrier which puts the reference into the satb buffer
 483 //    to indicate that someone holds a strong reference to the object the
 484 //    weak ref points to!
 485 address TemplateInterpreterGenerator::generate_Reference_get_entry(void) {
 486   // Code: _aload_0, _getfield, _areturn
 487   // parameter size = 1
 488   //
 489   // The code that gets generated by this routine is split into 2 parts:
 490   //    1. the "intrinsified" code for G1 (or any SATB based GC),
 491   //    2. the slow path - which is an expansion of the regular method entry.
 492   //
 493   // Notes:
 494   // * In the G1 code we do not check whether we need to block for
 495   //   a safepoint. If G1 is enabled then we must execute the specialized
 496   //   code for Reference.get (except when the Reference object is null)
 497   //   so that we can log the value in the referent field with an SATB
 498   //   update buffer.
 499   //   If the code for the getfield template is modified so that the
 500   //   G1 pre-barrier code is executed when the current method is
 501   //   Reference.get() then going through the normal method entry
 502   //   will be fine.
 503   // * The G1 code can, however, check the receiver object (the instance
 504   //   of java.lang.Reference) and jump to the slow path if null. If the
 505   //   Reference object is null then we obviously cannot fetch the referent
 506   //   and so we don't need to call the G1 pre-barrier. Thus we can use the
 507   //   regular method entry code to generate the NPE.
 508   //
 509 
 510   if (UseG1GC) {
 511     address entry = __ pc();
 512 
 513     const int referent_offset = java_lang_ref_Reference::referent_offset;
 514     guarantee(referent_offset > 0, "referent offset not initialized");
 515 
 516     Label slow_path;
 517 
 518     // Debugging not possible, so can't use __ skip_if_jvmti_mode(slow_path, GR31_SCRATCH);
 519 
 520     // In the G1 code we don't check if we need to reach a safepoint. We
 521     // continue and the thread will safepoint at the next bytecode dispatch.
 522 
 523     // If the receiver is null then it is OK to jump to the slow path.
 524     __ ld(R3_RET, Interpreter::stackElementSize, R15_esp); // get receiver
 525 
 526     // Check if receiver == NULL and go the slow path.
 527     __ cmpdi(CCR0, R3_RET, 0);
 528     __ beq(CCR0, slow_path);
 529 
 530     // Load the value of the referent field.
 531     __ load_heap_oop(R3_RET, referent_offset, R3_RET);
 532 
 533     // Generate the G1 pre-barrier code to log the value of
 534     // the referent field in an SATB buffer. Note with
 535     // these parameters the pre-barrier does not generate
 536     // the load of the previous value.
 537 
 538     // Restore caller sp for c2i case.
 539 #ifdef ASSERT
 540       __ ld(R9_ARG7, 0, R1_SP);
 541       __ ld(R10_ARG8, 0, R21_sender_SP);
 542       __ cmpd(CCR0, R9_ARG7, R10_ARG8);
 543       __ asm_assert_eq("backlink", 0x544);
 544 #endif // ASSERT
 545     __ mr(R1_SP, R21_sender_SP); // Cut the stack back to where the caller started.
 546 
 547     __ g1_write_barrier_pre(noreg,         // obj
 548                             noreg,         // offset
 549                             R3_RET,        // pre_val
 550                             R11_scratch1,  // tmp
 551                             R12_scratch2,  // tmp
 552                             true);         // needs_frame
 553 
 554     __ blr();
 555 
 556     // Generate regular method entry.
 557     __ bind(slow_path);
 558     __ jump_to_entry(Interpreter::entry_for_kind(Interpreter::zerolocals), R11_scratch1);
 559     return entry;
 560   }
 561 
 562   return NULL;
 563 }
 564 
 565 address TemplateInterpreterGenerator::generate_StackOverflowError_handler() {
 566   address entry = __ pc();
 567 
 568   // Expression stack must be empty before entering the VM if an
 569   // exception happened.
 570   __ empty_expression_stack();
 571   // Throw exception.
 572   __ call_VM(noreg,
 573              CAST_FROM_FN_PTR(address,
 574                               InterpreterRuntime::throw_StackOverflowError));
 575   return entry;
 576 }
 577 
 578 address TemplateInterpreterGenerator::generate_ArrayIndexOutOfBounds_handler(const char* name) {
 579   address entry = __ pc();
 580   __ empty_expression_stack();
 581   __ load_const_optimized(R4_ARG2, (address) name);
 582   // Index is in R17_tos.
 583   __ mr(R5_ARG3, R17_tos);
 584   __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_ArrayIndexOutOfBoundsException));
 585   return entry;
 586 }
 587 
 588 #if 0
 589 // Call special ClassCastException constructor taking object to cast
 590 // and target class as arguments.
 591 address TemplateInterpreterGenerator::generate_ClassCastException_verbose_handler() {
 592   address entry = __ pc();
 593 
 594   // Expression stack must be empty before entering the VM if an
 595   // exception happened.
 596   __ empty_expression_stack();
 597 
 598   // Thread will be loaded to R3_ARG1.
 599   // Target class oop is in register R5_ARG3 by convention!
 600   __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_ClassCastException_verbose), R17_tos, R5_ARG3);
 601   // Above call must not return here since exception pending.
 602   DEBUG_ONLY(__ should_not_reach_here();)
 603   return entry;
 604 }
 605 #endif
 606 
 607 address TemplateInterpreterGenerator::generate_ClassCastException_handler() {
 608   address entry = __ pc();
 609   // Expression stack must be empty before entering the VM if an
 610   // exception happened.
 611   __ empty_expression_stack();
 612 
 613   // Load exception object.
 614   // Thread will be loaded to R3_ARG1.
 615   __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_ClassCastException), R17_tos);
 616 #ifdef ASSERT
 617   // Above call must not return here since exception pending.
 618   __ should_not_reach_here();
 619 #endif
 620   return entry;
 621 }
 622 
 623 address TemplateInterpreterGenerator::generate_exception_handler_common(const char* name, const char* message, bool pass_oop) {
 624   address entry = __ pc();
 625   //__ untested("generate_exception_handler_common");
 626   Register Rexception = R17_tos;
 627 
 628   // Expression stack must be empty before entering the VM if an exception happened.
 629   __ empty_expression_stack();
 630 
 631   __ load_const_optimized(R4_ARG2, (address) name, R11_scratch1);
 632   if (pass_oop) {
 633     __ mr(R5_ARG3, Rexception);
 634     __ call_VM(Rexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_klass_exception), false);
 635   } else {
 636     __ load_const_optimized(R5_ARG3, (address) message, R11_scratch1);
 637     __ call_VM(Rexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_exception), false);
 638   }
 639 
 640   // Throw exception.
 641   __ mr(R3_ARG1, Rexception);
 642   __ load_const_optimized(R11_scratch1, Interpreter::throw_exception_entry(), R12_scratch2);
 643   __ mtctr(R11_scratch1);
 644   __ bctr();
 645 
 646   return entry;
 647 }
 648 
 649 address TemplateInterpreterGenerator::generate_continuation_for(TosState state) {
 650   address entry = __ pc();
 651   __ unimplemented("generate_continuation_for");
 652   return entry;
 653 }
 654 
 655 // This entry is returned to when a call returns to the interpreter.
 656 // When we arrive here, we expect that the callee stack frame is already popped.
 657 address TemplateInterpreterGenerator::generate_return_entry_for(TosState state, int step, size_t index_size) {
 658   address entry = __ pc();
 659 
 660   // Move the value out of the return register back to the TOS cache of current frame.
 661   switch (state) {
 662     case ltos:
 663     case btos:
 664     case ztos:
 665     case ctos:
 666     case stos:
 667     case atos:
 668     case itos: __ mr(R17_tos, R3_RET); break;   // RET -> TOS cache
 669     case ftos:
 670     case dtos: __ fmr(F15_ftos, F1_RET); break; // TOS cache -> GR_FRET
 671     case vtos: break;                           // Nothing to do, this was a void return.
 672     default  : ShouldNotReachHere();
 673   }
 674 
 675   __ restore_interpreter_state(R11_scratch1); // Sets R11_scratch1 = fp.
 676   __ ld(R12_scratch2, _ijava_state_neg(top_frame_sp), R11_scratch1);
 677   __ resize_frame_absolute(R12_scratch2, R11_scratch1, R0);
 678 
 679   // Compiled code destroys templateTableBase, reload.
 680   __ load_const_optimized(R25_templateTableBase, (address)Interpreter::dispatch_table((TosState)0), R12_scratch2);
 681 
 682   if (state == atos) {
 683     __ profile_return_type(R3_RET, R11_scratch1, R12_scratch2);
 684   }
 685 
 686   const Register cache = R11_scratch1;
 687   const Register size  = R12_scratch2;
 688   __ get_cache_and_index_at_bcp(cache, 1, index_size);
 689 
 690   // Get least significant byte of 64 bit value:
 691 #if defined(VM_LITTLE_ENDIAN)
 692   __ lbz(size, in_bytes(ConstantPoolCache::base_offset() + ConstantPoolCacheEntry::flags_offset()), cache);
 693 #else
 694   __ lbz(size, in_bytes(ConstantPoolCache::base_offset() + ConstantPoolCacheEntry::flags_offset()) + 7, cache);
 695 #endif
 696   __ sldi(size, size, Interpreter::logStackElementSize);
 697   __ add(R15_esp, R15_esp, size);
 698   __ dispatch_next(state, step);
 699   return entry;
 700 }
 701 
 702 address TemplateInterpreterGenerator::generate_deopt_entry_for(TosState state, int step) {
 703   address entry = __ pc();
 704   // If state != vtos, we're returning from a native method, which put it's result
 705   // into the result register. So move the value out of the return register back
 706   // to the TOS cache of current frame.
 707 
 708   switch (state) {
 709     case ltos:
 710     case btos:
 711     case ztos:
 712     case ctos:
 713     case stos:
 714     case atos:
 715     case itos: __ mr(R17_tos, R3_RET); break;   // GR_RET -> TOS cache
 716     case ftos:
 717     case dtos: __ fmr(F15_ftos, F1_RET); break; // TOS cache -> GR_FRET
 718     case vtos: break;                           // Nothing to do, this was a void return.
 719     default  : ShouldNotReachHere();
 720   }
 721 
 722   // Load LcpoolCache @@@ should be already set!
 723   __ get_constant_pool_cache(R27_constPoolCache);
 724 
 725   // Handle a pending exception, fall through if none.
 726   __ check_and_forward_exception(R11_scratch1, R12_scratch2);
 727 
 728   // Start executing bytecodes.
 729   __ dispatch_next(state, step);
 730 
 731   return entry;
 732 }
 733 
 734 address TemplateInterpreterGenerator::generate_safept_entry_for(TosState state, address runtime_entry) {
 735   address entry = __ pc();
 736 
 737   __ push(state);
 738   __ call_VM(noreg, runtime_entry);
 739   __ dispatch_via(vtos, Interpreter::_normal_table.table_for(vtos));
 740 
 741   return entry;
 742 }
 743 
 744 // Helpers for commoning out cases in the various type of method entries.
 745 
 746 // Increment invocation count & check for overflow.
 747 //
 748 // Note: checking for negative value instead of overflow
 749 //       so we have a 'sticky' overflow test.
 750 //
 751 void TemplateInterpreterGenerator::generate_counter_incr(Label* overflow, Label* profile_method, Label* profile_method_continue) {
 752   // Note: In tiered we increment either counters in method or in MDO depending if we're profiling or not.
 753   Register Rscratch1   = R11_scratch1;
 754   Register Rscratch2   = R12_scratch2;
 755   Register R3_counters = R3_ARG1;
 756   Label done;
 757 
 758   if (TieredCompilation) {
 759     const int increment = InvocationCounter::count_increment;
 760     Label no_mdo;
 761     if (ProfileInterpreter) {
 762       const Register Rmdo = R3_counters;
 763       // If no method data exists, go to profile_continue.
 764       __ ld(Rmdo, in_bytes(Method::method_data_offset()), R19_method);
 765       __ cmpdi(CCR0, Rmdo, 0);
 766       __ beq(CCR0, no_mdo);
 767 
 768       // Increment invocation counter in the MDO.
 769       const int mdo_ic_offs = in_bytes(MethodData::invocation_counter_offset()) + in_bytes(InvocationCounter::counter_offset());
 770       __ lwz(Rscratch2, mdo_ic_offs, Rmdo);
 771       __ lwz(Rscratch1, in_bytes(MethodData::invoke_mask_offset()), Rmdo);
 772       __ addi(Rscratch2, Rscratch2, increment);
 773       __ stw(Rscratch2, mdo_ic_offs, Rmdo);
 774       __ and_(Rscratch1, Rscratch2, Rscratch1);
 775       __ bne(CCR0, done);
 776       __ b(*overflow);
 777     }
 778 
 779     // Increment counter in MethodCounters*.
 780     const int mo_ic_offs = in_bytes(MethodCounters::invocation_counter_offset()) + in_bytes(InvocationCounter::counter_offset());
 781     __ bind(no_mdo);
 782     __ get_method_counters(R19_method, R3_counters, done);
 783     __ lwz(Rscratch2, mo_ic_offs, R3_counters);
 784     __ lwz(Rscratch1, in_bytes(MethodCounters::invoke_mask_offset()), R3_counters);
 785     __ addi(Rscratch2, Rscratch2, increment);
 786     __ stw(Rscratch2, mo_ic_offs, R3_counters);
 787     __ and_(Rscratch1, Rscratch2, Rscratch1);
 788     __ beq(CCR0, *overflow);
 789 
 790     __ bind(done);
 791 
 792   } else {
 793 
 794     // Update standard invocation counters.
 795     Register Rsum_ivc_bec = R4_ARG2;
 796     __ get_method_counters(R19_method, R3_counters, done);
 797     __ increment_invocation_counter(R3_counters, Rsum_ivc_bec, R12_scratch2);
 798     // Increment interpreter invocation counter.
 799     if (ProfileInterpreter) {  // %%% Merge this into methodDataOop.
 800       __ lwz(R12_scratch2, in_bytes(MethodCounters::interpreter_invocation_counter_offset()), R3_counters);
 801       __ addi(R12_scratch2, R12_scratch2, 1);
 802       __ stw(R12_scratch2, in_bytes(MethodCounters::interpreter_invocation_counter_offset()), R3_counters);
 803     }
 804     // Check if we must create a method data obj.
 805     if (ProfileInterpreter && profile_method != NULL) {
 806       const Register profile_limit = Rscratch1;
 807       __ lwz(profile_limit, in_bytes(MethodCounters::interpreter_profile_limit_offset()), R3_counters);
 808       // Test to see if we should create a method data oop.
 809       __ cmpw(CCR0, Rsum_ivc_bec, profile_limit);
 810       __ blt(CCR0, *profile_method_continue);
 811       // If no method data exists, go to profile_method.
 812       __ test_method_data_pointer(*profile_method);
 813     }
 814     // Finally check for counter overflow.
 815     if (overflow) {
 816       const Register invocation_limit = Rscratch1;
 817       __ lwz(invocation_limit, in_bytes(MethodCounters::interpreter_invocation_limit_offset()), R3_counters);
 818       __ cmpw(CCR0, Rsum_ivc_bec, invocation_limit);
 819       __ bge(CCR0, *overflow);
 820     }
 821 
 822     __ bind(done);
 823   }
 824 }
 825 
 826 // Generate code to initiate compilation on invocation counter overflow.
 827 void TemplateInterpreterGenerator::generate_counter_overflow(Label& continue_entry) {
 828   // Generate code to initiate compilation on the counter overflow.
 829 
 830   // InterpreterRuntime::frequency_counter_overflow takes one arguments,
 831   // which indicates if the counter overflow occurs at a backwards branch (NULL bcp)
 832   // We pass zero in.
 833   // The call returns the address of the verified entry point for the method or NULL
 834   // if the compilation did not complete (either went background or bailed out).
 835   //
 836   // Unlike the C++ interpreter above: Check exceptions!
 837   // Assumption: Caller must set the flag "do_not_unlock_if_sychronized" if the monitor of a sync'ed
 838   // method has not yet been created. Thus, no unlocking of a non-existing monitor can occur.
 839 
 840   __ li(R4_ARG2, 0);
 841   __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::frequency_counter_overflow), R4_ARG2, true);
 842 
 843   // Returns verified_entry_point or NULL.
 844   // We ignore it in any case.
 845   __ b(continue_entry);
 846 }
 847 
 848 // See if we've got enough room on the stack for locals plus overhead below
 849 // JavaThread::stack_overflow_limit(). If not, throw a StackOverflowError
 850 // without going through the signal handler, i.e., reserved and yellow zones
 851 // will not be made usable. The shadow zone must suffice to handle the
 852 // overflow.
 853 //
 854 // Kills Rmem_frame_size, Rscratch1.
 855 void TemplateInterpreterGenerator::generate_stack_overflow_check(Register Rmem_frame_size, Register Rscratch1) {
 856   Label done;
 857   assert_different_registers(Rmem_frame_size, Rscratch1);
 858 
 859   BLOCK_COMMENT("stack_overflow_check_with_compare {");
 860   __ sub(Rmem_frame_size, R1_SP, Rmem_frame_size);
 861   __ ld(Rscratch1, thread_(stack_overflow_limit));
 862   __ cmpld(CCR0/*is_stack_overflow*/, Rmem_frame_size, Rscratch1);
 863   __ bgt(CCR0/*is_stack_overflow*/, done);
 864 
 865   // The stack overflows. Load target address of the runtime stub and call it.
 866   assert(StubRoutines::throw_StackOverflowError_entry() != NULL, "generated in wrong order");
 867   __ load_const_optimized(Rscratch1, (StubRoutines::throw_StackOverflowError_entry()), R0);
 868   __ mtctr(Rscratch1);
 869   // Restore caller_sp.
 870 #ifdef ASSERT
 871   __ ld(Rscratch1, 0, R1_SP);
 872   __ ld(R0, 0, R21_sender_SP);
 873   __ cmpd(CCR0, R0, Rscratch1);
 874   __ asm_assert_eq("backlink", 0x547);
 875 #endif // ASSERT
 876   __ mr(R1_SP, R21_sender_SP);
 877   __ bctr();
 878 
 879   __ align(32, 12);
 880   __ bind(done);
 881   BLOCK_COMMENT("} stack_overflow_check_with_compare");
 882 }
 883 
 884 // Lock the current method, interpreter register window must be set up!
 885 void TemplateInterpreterGenerator::lock_method(Register Rflags, Register Rscratch1, Register Rscratch2, bool flags_preloaded) {
 886   const Register Robj_to_lock = Rscratch2;
 887 
 888   {
 889     if (!flags_preloaded) {
 890       __ lwz(Rflags, method_(access_flags));
 891     }
 892 
 893 #ifdef ASSERT
 894     // Check if methods needs synchronization.
 895     {
 896       Label Lok;
 897       __ testbitdi(CCR0, R0, Rflags, JVM_ACC_SYNCHRONIZED_BIT);
 898       __ btrue(CCR0,Lok);
 899       __ stop("method doesn't need synchronization");
 900       __ bind(Lok);
 901     }
 902 #endif // ASSERT
 903   }
 904 
 905   // Get synchronization object to Rscratch2.
 906   {
 907     Label Lstatic;
 908     Label Ldone;
 909 
 910     __ testbitdi(CCR0, R0, Rflags, JVM_ACC_STATIC_BIT);
 911     __ btrue(CCR0, Lstatic);
 912 
 913     // Non-static case: load receiver obj from stack and we're done.
 914     __ ld(Robj_to_lock, R18_locals);
 915     __ b(Ldone);
 916 
 917     __ bind(Lstatic); // Static case: Lock the java mirror
 918     __ load_mirror(Robj_to_lock, R19_method);
 919 
 920     __ bind(Ldone);
 921     __ verify_oop(Robj_to_lock);
 922   }
 923 
 924   // Got the oop to lock => execute!
 925   __ add_monitor_to_stack(true, Rscratch1, R0);
 926 
 927   __ std(Robj_to_lock, BasicObjectLock::obj_offset_in_bytes(), R26_monitor);
 928   __ lock_object(R26_monitor, Robj_to_lock);
 929 }
 930 
 931 // Generate a fixed interpreter frame for pure interpreter
 932 // and I2N native transition frames.
 933 //
 934 // Before (stack grows downwards):
 935 //
 936 //         |  ...         |
 937 //         |------------- |
 938 //         |  java arg0   |
 939 //         |  ...         |
 940 //         |  java argn   |
 941 //         |              |   <-   R15_esp
 942 //         |              |
 943 //         |--------------|
 944 //         | abi_112      |
 945 //         |              |   <-   R1_SP
 946 //         |==============|
 947 //
 948 //
 949 // After:
 950 //
 951 //         |  ...         |
 952 //         |  java arg0   |<-   R18_locals
 953 //         |  ...         |
 954 //         |  java argn   |
 955 //         |--------------|
 956 //         |              |
 957 //         |  java locals |
 958 //         |              |
 959 //         |--------------|
 960 //         |  abi_48      |
 961 //         |==============|
 962 //         |              |
 963 //         |   istate     |
 964 //         |              |
 965 //         |--------------|
 966 //         |   monitor    |<-   R26_monitor
 967 //         |--------------|
 968 //         |              |<-   R15_esp
 969 //         | expression   |
 970 //         | stack        |
 971 //         |              |
 972 //         |--------------|
 973 //         |              |
 974 //         | abi_112      |<-   R1_SP
 975 //         |==============|
 976 //
 977 // The top most frame needs an abi space of 112 bytes. This space is needed,
 978 // since we call to c. The c function may spill their arguments to the caller
 979 // frame. When we call to java, we don't need these spill slots. In order to save
 980 // space on the stack, we resize the caller. However, java locals reside in
 981 // the caller frame and the frame has to be increased. The frame_size for the
 982 // current frame was calculated based on max_stack as size for the expression
 983 // stack. At the call, just a part of the expression stack might be used.
 984 // We don't want to waste this space and cut the frame back accordingly.
 985 // The resulting amount for resizing is calculated as follows:
 986 // resize =   (number_of_locals - number_of_arguments) * slot_size
 987 //          + (R1_SP - R15_esp) + 48
 988 //
 989 // The size for the callee frame is calculated:
 990 // framesize = 112 + max_stack + monitor + state_size
 991 //
 992 // maxstack:   Max number of slots on the expression stack, loaded from the method.
 993 // monitor:    We statically reserve room for one monitor object.
 994 // state_size: We save the current state of the interpreter to this area.
 995 //
 996 void TemplateInterpreterGenerator::generate_fixed_frame(bool native_call, Register Rsize_of_parameters, Register Rsize_of_locals) {
 997   Register parent_frame_resize = R6_ARG4, // Frame will grow by this number of bytes.
 998            top_frame_size      = R7_ARG5,
 999            Rconst_method       = R8_ARG6;
1000 
1001   assert_different_registers(Rsize_of_parameters, Rsize_of_locals, parent_frame_resize, top_frame_size);
1002 
1003   __ ld(Rconst_method, method_(const));
1004   __ lhz(Rsize_of_parameters /* number of params */,
1005          in_bytes(ConstMethod::size_of_parameters_offset()), Rconst_method);
1006   if (native_call) {
1007     // If we're calling a native method, we reserve space for the worst-case signature
1008     // handler varargs vector, which is max(Argument::n_register_parameters, parameter_count+2).
1009     // We add two slots to the parameter_count, one for the jni
1010     // environment and one for a possible native mirror.
1011     Label skip_native_calculate_max_stack;
1012     __ addi(top_frame_size, Rsize_of_parameters, 2);
1013     __ cmpwi(CCR0, top_frame_size, Argument::n_register_parameters);
1014     __ bge(CCR0, skip_native_calculate_max_stack);
1015     __ li(top_frame_size, Argument::n_register_parameters);
1016     __ bind(skip_native_calculate_max_stack);
1017     __ sldi(Rsize_of_parameters, Rsize_of_parameters, Interpreter::logStackElementSize);
1018     __ sldi(top_frame_size, top_frame_size, Interpreter::logStackElementSize);
1019     __ sub(parent_frame_resize, R1_SP, R15_esp); // <0, off by Interpreter::stackElementSize!
1020     assert(Rsize_of_locals == noreg, "Rsize_of_locals not initialized"); // Only relevant value is Rsize_of_parameters.
1021   } else {
1022     __ lhz(Rsize_of_locals /* number of params */, in_bytes(ConstMethod::size_of_locals_offset()), Rconst_method);
1023     __ sldi(Rsize_of_parameters, Rsize_of_parameters, Interpreter::logStackElementSize);
1024     __ sldi(Rsize_of_locals, Rsize_of_locals, Interpreter::logStackElementSize);
1025     __ lhz(top_frame_size, in_bytes(ConstMethod::max_stack_offset()), Rconst_method);
1026     __ sub(R11_scratch1, Rsize_of_locals, Rsize_of_parameters); // >=0
1027     __ sub(parent_frame_resize, R1_SP, R15_esp); // <0, off by Interpreter::stackElementSize!
1028     __ sldi(top_frame_size, top_frame_size, Interpreter::logStackElementSize);
1029     __ add(parent_frame_resize, parent_frame_resize, R11_scratch1);
1030   }
1031 
1032   // Compute top frame size.
1033   __ addi(top_frame_size, top_frame_size, frame::abi_reg_args_size + frame::ijava_state_size);
1034 
1035   // Cut back area between esp and max_stack.
1036   __ addi(parent_frame_resize, parent_frame_resize, frame::abi_minframe_size - Interpreter::stackElementSize);
1037 
1038   __ round_to(top_frame_size, frame::alignment_in_bytes);
1039   __ round_to(parent_frame_resize, frame::alignment_in_bytes);
1040   // parent_frame_resize = (locals-parameters) - (ESP-SP-ABI48) Rounded to frame alignment size.
1041   // Enlarge by locals-parameters (not in case of native_call), shrink by ESP-SP-ABI48.
1042 
1043   if (!native_call) {
1044     // Stack overflow check.
1045     // Native calls don't need the stack size check since they have no
1046     // expression stack and the arguments are already on the stack and
1047     // we only add a handful of words to the stack.
1048     __ add(R11_scratch1, parent_frame_resize, top_frame_size);
1049     generate_stack_overflow_check(R11_scratch1, R12_scratch2);
1050   }
1051 
1052   // Set up interpreter state registers.
1053 
1054   __ add(R18_locals, R15_esp, Rsize_of_parameters);
1055   __ ld(R27_constPoolCache, in_bytes(ConstMethod::constants_offset()), Rconst_method);
1056   __ ld(R27_constPoolCache, ConstantPool::cache_offset_in_bytes(), R27_constPoolCache);
1057 
1058   // Set method data pointer.
1059   if (ProfileInterpreter) {
1060     Label zero_continue;
1061     __ ld(R28_mdx, method_(method_data));
1062     __ cmpdi(CCR0, R28_mdx, 0);
1063     __ beq(CCR0, zero_continue);
1064     __ addi(R28_mdx, R28_mdx, in_bytes(MethodData::data_offset()));
1065     __ bind(zero_continue);
1066   }
1067 
1068   if (native_call) {
1069     __ li(R14_bcp, 0); // Must initialize.
1070   } else {
1071     __ add(R14_bcp, in_bytes(ConstMethod::codes_offset()), Rconst_method);
1072   }
1073 
1074   // Resize parent frame.
1075   __ mflr(R12_scratch2);
1076   __ neg(parent_frame_resize, parent_frame_resize);
1077   __ resize_frame(parent_frame_resize, R11_scratch1);
1078   __ std(R12_scratch2, _abi(lr), R1_SP);
1079 
1080   __ addi(R26_monitor, R1_SP, - frame::ijava_state_size);
1081   __ addi(R15_esp, R26_monitor, - Interpreter::stackElementSize);
1082 
1083   // Get mirror and store it in the frame as GC root for this Method*.
1084   __ load_mirror(R12_scratch2, R19_method);
1085 
1086   // Store values.
1087   // R15_esp, R14_bcp, R26_monitor, R28_mdx are saved at java calls
1088   // in InterpreterMacroAssembler::call_from_interpreter.
1089   __ std(R19_method, _ijava_state_neg(method), R1_SP);
1090   __ std(R12_scratch2, _ijava_state_neg(mirror), R1_SP);
1091   __ std(R21_sender_SP, _ijava_state_neg(sender_sp), R1_SP);
1092   __ std(R27_constPoolCache, _ijava_state_neg(cpoolCache), R1_SP);
1093   __ std(R18_locals, _ijava_state_neg(locals), R1_SP);
1094 
1095   // Note: esp, bcp, monitor, mdx live in registers. Hence, the correct version can only
1096   // be found in the frame after save_interpreter_state is done. This is always true
1097   // for non-top frames. But when a signal occurs, dumping the top frame can go wrong,
1098   // because e.g. frame::interpreter_frame_bcp() will not access the correct value
1099   // (Enhanced Stack Trace).
1100   // The signal handler does not save the interpreter state into the frame.
1101   __ li(R0, 0);
1102 #ifdef ASSERT
1103   // Fill remaining slots with constants.
1104   __ load_const_optimized(R11_scratch1, 0x5afe);
1105   __ load_const_optimized(R12_scratch2, 0xdead);
1106 #endif
1107   // We have to initialize some frame slots for native calls (accessed by GC).
1108   if (native_call) {
1109     __ std(R26_monitor, _ijava_state_neg(monitors), R1_SP);
1110     __ std(R14_bcp, _ijava_state_neg(bcp), R1_SP);
1111     if (ProfileInterpreter) { __ std(R28_mdx, _ijava_state_neg(mdx), R1_SP); }
1112   }
1113 #ifdef ASSERT
1114   else {
1115     __ std(R12_scratch2, _ijava_state_neg(monitors), R1_SP);
1116     __ std(R12_scratch2, _ijava_state_neg(bcp), R1_SP);
1117     __ std(R12_scratch2, _ijava_state_neg(mdx), R1_SP);
1118   }
1119   __ std(R11_scratch1, _ijava_state_neg(ijava_reserved), R1_SP);
1120   __ std(R12_scratch2, _ijava_state_neg(esp), R1_SP);
1121   __ std(R12_scratch2, _ijava_state_neg(lresult), R1_SP);
1122   __ std(R12_scratch2, _ijava_state_neg(fresult), R1_SP);
1123 #endif
1124   __ subf(R12_scratch2, top_frame_size, R1_SP);
1125   __ std(R0, _ijava_state_neg(oop_tmp), R1_SP);
1126   __ std(R12_scratch2, _ijava_state_neg(top_frame_sp), R1_SP);
1127 
1128   // Push top frame.
1129   __ push_frame(top_frame_size, R11_scratch1);
1130 }
1131 
1132 // End of helpers
1133 
1134 address TemplateInterpreterGenerator::generate_math_entry(AbstractInterpreter::MethodKind kind) {
1135   if (!Interpreter::math_entry_available(kind)) {
1136     NOT_PRODUCT(__ should_not_reach_here();)
1137     return NULL;
1138   }
1139 
1140   address entry = __ pc();
1141 
1142   __ lfd(F1_RET, Interpreter::stackElementSize, R15_esp);
1143 
1144   // Pop c2i arguments (if any) off when we return.
1145 #ifdef ASSERT
1146   __ ld(R9_ARG7, 0, R1_SP);
1147   __ ld(R10_ARG8, 0, R21_sender_SP);
1148   __ cmpd(CCR0, R9_ARG7, R10_ARG8);
1149   __ asm_assert_eq("backlink", 0x545);
1150 #endif // ASSERT
1151   __ mr(R1_SP, R21_sender_SP); // Cut the stack back to where the caller started.
1152 
1153   if (kind == Interpreter::java_lang_math_sqrt) {
1154     __ fsqrt(F1_RET, F1_RET);
1155   } else if (kind == Interpreter::java_lang_math_abs) {
1156     __ fabs(F1_RET, F1_RET);
1157   } else {
1158     ShouldNotReachHere();
1159   }
1160 
1161   // And we're done.
1162   __ blr();
1163 
1164   __ flush();
1165 
1166   return entry;
1167 }
1168 
1169 void TemplateInterpreterGenerator::bang_stack_shadow_pages(bool native_call) {
1170   // Quick & dirty stack overflow checking: bang the stack & handle trap.
1171   // Note that we do the banging after the frame is setup, since the exception
1172   // handling code expects to find a valid interpreter frame on the stack.
1173   // Doing the banging earlier fails if the caller frame is not an interpreter
1174   // frame.
1175   // (Also, the exception throwing code expects to unlock any synchronized
1176   // method receiever, so do the banging after locking the receiver.)
1177 
1178   // Bang each page in the shadow zone. We can't assume it's been done for
1179   // an interpreter frame with greater than a page of locals, so each page
1180   // needs to be checked.  Only true for non-native.
1181   if (UseStackBanging) {
1182     const int page_size = os::vm_page_size();
1183     const int n_shadow_pages = ((int)JavaThread::stack_shadow_zone_size()) / page_size;
1184     const int start_page = native_call ? n_shadow_pages : 1;
1185     BLOCK_COMMENT("bang_stack_shadow_pages:");
1186     for (int pages = start_page; pages <= n_shadow_pages; pages++) {
1187       __ bang_stack_with_offset(pages*page_size);
1188     }
1189   }
1190 }
1191 
1192 // Interpreter stub for calling a native method. (asm interpreter)
1193 // This sets up a somewhat different looking stack for calling the
1194 // native method than the typical interpreter frame setup.
1195 //
1196 // On entry:
1197 //   R19_method    - method
1198 //   R16_thread    - JavaThread*
1199 //   R15_esp       - intptr_t* sender tos
1200 //
1201 //   abstract stack (grows up)
1202 //     [  IJava (caller of JNI callee)  ]  <-- ASP
1203 //        ...
1204 address TemplateInterpreterGenerator::generate_native_entry(bool synchronized) {
1205 
1206   address entry = __ pc();
1207 
1208   const bool inc_counter = UseCompiler || CountCompiledCalls || LogTouchedMethods;
1209 
1210   // -----------------------------------------------------------------------------
1211   // Allocate a new frame that represents the native callee (i2n frame).
1212   // This is not a full-blown interpreter frame, but in particular, the
1213   // following registers are valid after this:
1214   // - R19_method
1215   // - R18_local (points to start of arguments to native function)
1216   //
1217   //   abstract stack (grows up)
1218   //     [  IJava (caller of JNI callee)  ]  <-- ASP
1219   //        ...
1220 
1221   const Register signature_handler_fd = R11_scratch1;
1222   const Register pending_exception    = R0;
1223   const Register result_handler_addr  = R31;
1224   const Register native_method_fd     = R11_scratch1;
1225   const Register access_flags         = R22_tmp2;
1226   const Register active_handles       = R11_scratch1; // R26_monitor saved to state.
1227   const Register sync_state           = R12_scratch2;
1228   const Register sync_state_addr      = sync_state;   // Address is dead after use.
1229   const Register suspend_flags        = R11_scratch1;
1230 
1231   //=============================================================================
1232   // Allocate new frame and initialize interpreter state.
1233 
1234   Label exception_return;
1235   Label exception_return_sync_check;
1236   Label stack_overflow_return;
1237 
1238   // Generate new interpreter state and jump to stack_overflow_return in case of
1239   // a stack overflow.
1240   //generate_compute_interpreter_state(stack_overflow_return);
1241 
1242   Register size_of_parameters = R22_tmp2;
1243 
1244   generate_fixed_frame(true, size_of_parameters, noreg /* unused */);
1245 
1246   //=============================================================================
1247   // Increment invocation counter. On overflow, entry to JNI method
1248   // will be compiled.
1249   Label invocation_counter_overflow, continue_after_compile;
1250   if (inc_counter) {
1251     if (synchronized) {
1252       // Since at this point in the method invocation the exception handler
1253       // would try to exit the monitor of synchronized methods which hasn't
1254       // been entered yet, we set the thread local variable
1255       // _do_not_unlock_if_synchronized to true. If any exception was thrown by
1256       // runtime, exception handling i.e. unlock_if_synchronized_method will
1257       // check this thread local flag.
1258       // This flag has two effects, one is to force an unwind in the topmost
1259       // interpreter frame and not perform an unlock while doing so.
1260       __ li(R0, 1);
1261       __ stb(R0, in_bytes(JavaThread::do_not_unlock_if_synchronized_offset()), R16_thread);
1262     }
1263     generate_counter_incr(&invocation_counter_overflow, NULL, NULL);
1264 
1265     BIND(continue_after_compile);
1266   }
1267 
1268   bang_stack_shadow_pages(true);
1269 
1270   if (inc_counter) {
1271     // Reset the _do_not_unlock_if_synchronized flag.
1272     if (synchronized) {
1273       __ li(R0, 0);
1274       __ stb(R0, in_bytes(JavaThread::do_not_unlock_if_synchronized_offset()), R16_thread);
1275     }
1276   }
1277 
1278   // access_flags = method->access_flags();
1279   // Load access flags.
1280   assert(access_flags->is_nonvolatile(),
1281          "access_flags must be in a non-volatile register");
1282   // Type check.
1283   assert(4 == sizeof(AccessFlags), "unexpected field size");
1284   __ lwz(access_flags, method_(access_flags));
1285 
1286   // We don't want to reload R19_method and access_flags after calls
1287   // to some helper functions.
1288   assert(R19_method->is_nonvolatile(),
1289          "R19_method must be a non-volatile register");
1290 
1291   // Check for synchronized methods. Must happen AFTER invocation counter
1292   // check, so method is not locked if counter overflows.
1293 
1294   if (synchronized) {
1295     lock_method(access_flags, R11_scratch1, R12_scratch2, true);
1296 
1297     // Update monitor in state.
1298     __ ld(R11_scratch1, 0, R1_SP);
1299     __ std(R26_monitor, _ijava_state_neg(monitors), R11_scratch1);
1300   }
1301 
1302   // jvmti/jvmpi support
1303   __ notify_method_entry();
1304 
1305   //=============================================================================
1306   // Get and call the signature handler.
1307 
1308   __ ld(signature_handler_fd, method_(signature_handler));
1309   Label call_signature_handler;
1310 
1311   __ cmpdi(CCR0, signature_handler_fd, 0);
1312   __ bne(CCR0, call_signature_handler);
1313 
1314   // Method has never been called. Either generate a specialized
1315   // handler or point to the slow one.
1316   //
1317   // Pass parameter 'false' to avoid exception check in call_VM.
1318   __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::prepare_native_call), R19_method, false);
1319 
1320   // Check for an exception while looking up the target method. If we
1321   // incurred one, bail.
1322   __ ld(pending_exception, thread_(pending_exception));
1323   __ cmpdi(CCR0, pending_exception, 0);
1324   __ bne(CCR0, exception_return_sync_check); // Has pending exception.
1325 
1326   // Reload signature handler, it may have been created/assigned in the meanwhile.
1327   __ ld(signature_handler_fd, method_(signature_handler));
1328   __ twi_0(signature_handler_fd); // Order wrt. load of klass mirror and entry point (isync is below).
1329 
1330   BIND(call_signature_handler);
1331 
1332   // Before we call the signature handler we push a new frame to
1333   // protect the interpreter frame volatile registers when we return
1334   // from jni but before we can get back to Java.
1335 
1336   // First set the frame anchor while the SP/FP registers are
1337   // convenient and the slow signature handler can use this same frame
1338   // anchor.
1339 
1340   // We have a TOP_IJAVA_FRAME here, which belongs to us.
1341   __ set_top_ijava_frame_at_SP_as_last_Java_frame(R1_SP, R12_scratch2/*tmp*/);
1342 
1343   // Now the interpreter frame (and its call chain) have been
1344   // invalidated and flushed. We are now protected against eager
1345   // being enabled in native code. Even if it goes eager the
1346   // registers will be reloaded as clean and we will invalidate after
1347   // the call so no spurious flush should be possible.
1348 
1349   // Call signature handler and pass locals address.
1350   //
1351   // Our signature handlers copy required arguments to the C stack
1352   // (outgoing C args), R3_ARG1 to R10_ARG8, and FARG1 to FARG13.
1353   __ mr(R3_ARG1, R18_locals);
1354 #if !defined(ABI_ELFv2)
1355   __ ld(signature_handler_fd, 0, signature_handler_fd);
1356 #endif
1357 
1358   __ call_stub(signature_handler_fd);
1359 
1360   // Remove the register parameter varargs slots we allocated in
1361   // compute_interpreter_state. SP+16 ends up pointing to the ABI
1362   // outgoing argument area.
1363   //
1364   // Not needed on PPC64.
1365   //__ add(SP, SP, Argument::n_register_parameters*BytesPerWord);
1366 
1367   assert(result_handler_addr->is_nonvolatile(), "result_handler_addr must be in a non-volatile register");
1368   // Save across call to native method.
1369   __ mr(result_handler_addr, R3_RET);
1370 
1371   __ isync(); // Acquire signature handler before trying to fetch the native entry point and klass mirror.
1372 
1373   // Set up fixed parameters and call the native method.
1374   // If the method is static, get mirror into R4_ARG2.
1375   {
1376     Label method_is_not_static;
1377     // Access_flags is non-volatile and still, no need to restore it.
1378 
1379     // Restore access flags.
1380     __ testbitdi(CCR0, R0, access_flags, JVM_ACC_STATIC_BIT);
1381     __ bfalse(CCR0, method_is_not_static);
1382 
1383     __ load_mirror(R12_scratch2, R19_method);
1384     // state->_native_mirror = mirror;
1385 
1386     __ ld(R11_scratch1, 0, R1_SP);
1387     __ std(R12_scratch2/*mirror*/, _ijava_state_neg(oop_tmp), R11_scratch1);
1388     // R4_ARG2 = &state->_oop_temp;
1389     __ addi(R4_ARG2, R11_scratch1, _ijava_state_neg(oop_tmp));
1390     BIND(method_is_not_static);
1391   }
1392 
1393   // At this point, arguments have been copied off the stack into
1394   // their JNI positions. Oops are boxed in-place on the stack, with
1395   // handles copied to arguments. The result handler address is in a
1396   // register.
1397 
1398   // Pass JNIEnv address as first parameter.
1399   __ addir(R3_ARG1, thread_(jni_environment));
1400 
1401   // Load the native_method entry before we change the thread state.
1402   __ ld(native_method_fd, method_(native_function));
1403 
1404   //=============================================================================
1405   // Transition from _thread_in_Java to _thread_in_native. As soon as
1406   // we make this change the safepoint code needs to be certain that
1407   // the last Java frame we established is good. The pc in that frame
1408   // just needs to be near here not an actual return address.
1409 
1410   // We use release_store_fence to update values like the thread state, where
1411   // we don't want the current thread to continue until all our prior memory
1412   // accesses (including the new thread state) are visible to other threads.
1413   __ li(R0, _thread_in_native);
1414   __ release();
1415 
1416   // TODO PPC port assert(4 == JavaThread::sz_thread_state(), "unexpected field size");
1417   __ stw(R0, thread_(thread_state));
1418 
1419   if (UseMembar) {
1420     __ fence();
1421   }
1422 
1423   //=============================================================================
1424   // Call the native method. Argument registers must not have been
1425   // overwritten since "__ call_stub(signature_handler);" (except for
1426   // ARG1 and ARG2 for static methods).
1427   __ call_c(native_method_fd);
1428 
1429   __ li(R0, 0);
1430   __ ld(R11_scratch1, 0, R1_SP);
1431   __ std(R3_RET, _ijava_state_neg(lresult), R11_scratch1);
1432   __ stfd(F1_RET, _ijava_state_neg(fresult), R11_scratch1);
1433   __ std(R0/*mirror*/, _ijava_state_neg(oop_tmp), R11_scratch1); // reset
1434 
1435   // Note: C++ interpreter needs the following here:
1436   // The frame_manager_lr field, which we use for setting the last
1437   // java frame, gets overwritten by the signature handler. Restore
1438   // it now.
1439   //__ get_PC_trash_LR(R11_scratch1);
1440   //__ std(R11_scratch1, _top_ijava_frame_abi(frame_manager_lr), R1_SP);
1441 
1442   // Because of GC R19_method may no longer be valid.
1443 
1444   // Block, if necessary, before resuming in _thread_in_Java state.
1445   // In order for GC to work, don't clear the last_Java_sp until after
1446   // blocking.
1447 
1448   //=============================================================================
1449   // Switch thread to "native transition" state before reading the
1450   // synchronization state. This additional state is necessary
1451   // because reading and testing the synchronization state is not
1452   // atomic w.r.t. GC, as this scenario demonstrates: Java thread A,
1453   // in _thread_in_native state, loads _not_synchronized and is
1454   // preempted. VM thread changes sync state to synchronizing and
1455   // suspends threads for GC. Thread A is resumed to finish this
1456   // native method, but doesn't block here since it didn't see any
1457   // synchronization in progress, and escapes.
1458 
1459   // We use release_store_fence to update values like the thread state, where
1460   // we don't want the current thread to continue until all our prior memory
1461   // accesses (including the new thread state) are visible to other threads.
1462   __ li(R0/*thread_state*/, _thread_in_native_trans);
1463   __ release();
1464   __ stw(R0/*thread_state*/, thread_(thread_state));
1465   if (UseMembar) {
1466     __ fence();
1467   }
1468   // Write serialization page so that the VM thread can do a pseudo remote
1469   // membar. We use the current thread pointer to calculate a thread
1470   // specific offset to write to within the page. This minimizes bus
1471   // traffic due to cache line collision.
1472   else {
1473     __ serialize_memory(R16_thread, R11_scratch1, R12_scratch2);
1474   }
1475 
1476   // Now before we return to java we must look for a current safepoint
1477   // (a new safepoint can not start since we entered native_trans).
1478   // We must check here because a current safepoint could be modifying
1479   // the callers registers right this moment.
1480 
1481   // Acquire isn't strictly necessary here because of the fence, but
1482   // sync_state is declared to be volatile, so we do it anyway
1483   // (cmp-br-isync on one path, release (same as acquire on PPC64) on the other path).
1484   int sync_state_offs = __ load_const_optimized(sync_state_addr, SafepointSynchronize::address_of_state(), /*temp*/R0, true);
1485 
1486   // TODO PPC port assert(4 == SafepointSynchronize::sz_state(), "unexpected field size");
1487   __ lwz(sync_state, sync_state_offs, sync_state_addr);
1488 
1489   // TODO PPC port assert(4 == Thread::sz_suspend_flags(), "unexpected field size");
1490   __ lwz(suspend_flags, thread_(suspend_flags));
1491 
1492   Label sync_check_done;
1493   Label do_safepoint;
1494   // No synchronization in progress nor yet synchronized.
1495   __ cmpwi(CCR0, sync_state, SafepointSynchronize::_not_synchronized);
1496   // Not suspended.
1497   __ cmpwi(CCR1, suspend_flags, 0);
1498 
1499   __ bne(CCR0, do_safepoint);
1500   __ beq(CCR1, sync_check_done);
1501   __ bind(do_safepoint);
1502   __ isync();
1503   // Block. We do the call directly and leave the current
1504   // last_Java_frame setup undisturbed. We must save any possible
1505   // native result across the call. No oop is present.
1506 
1507   __ mr(R3_ARG1, R16_thread);
1508 #if defined(ABI_ELFv2)
1509   __ call_c(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans),
1510             relocInfo::none);
1511 #else
1512   __ call_c(CAST_FROM_FN_PTR(FunctionDescriptor*, JavaThread::check_special_condition_for_native_trans),
1513             relocInfo::none);
1514 #endif
1515 
1516   __ bind(sync_check_done);
1517 
1518   //=============================================================================
1519   // <<<<<< Back in Interpreter Frame >>>>>
1520 
1521   // We are in thread_in_native_trans here and back in the normal
1522   // interpreter frame. We don't have to do anything special about
1523   // safepoints and we can switch to Java mode anytime we are ready.
1524 
1525   // Note: frame::interpreter_frame_result has a dependency on how the
1526   // method result is saved across the call to post_method_exit. For
1527   // native methods it assumes that the non-FPU/non-void result is
1528   // saved in _native_lresult and a FPU result in _native_fresult. If
1529   // this changes then the interpreter_frame_result implementation
1530   // will need to be updated too.
1531 
1532   // On PPC64, we have stored the result directly after the native call.
1533 
1534   //=============================================================================
1535   // Back in Java
1536 
1537   // We use release_store_fence to update values like the thread state, where
1538   // we don't want the current thread to continue until all our prior memory
1539   // accesses (including the new thread state) are visible to other threads.
1540   __ li(R0/*thread_state*/, _thread_in_Java);
1541   __ release();
1542   __ stw(R0/*thread_state*/, thread_(thread_state));
1543   if (UseMembar) {
1544     __ fence();
1545   }
1546 
1547   __ reset_last_Java_frame();
1548 
1549   // Jvmdi/jvmpi support. Whether we've got an exception pending or
1550   // not, and whether unlocking throws an exception or not, we notify
1551   // on native method exit. If we do have an exception, we'll end up
1552   // in the caller's context to handle it, so if we don't do the
1553   // notify here, we'll drop it on the floor.
1554   __ notify_method_exit(true/*native method*/,
1555                         ilgl /*illegal state (not used for native methods)*/,
1556                         InterpreterMacroAssembler::NotifyJVMTI,
1557                         false /*check_exceptions*/);
1558 
1559   //=============================================================================
1560   // Handle exceptions
1561 
1562   if (synchronized) {
1563     // Don't check for exceptions since we're still in the i2n frame. Do that
1564     // manually afterwards.
1565     __ unlock_object(R26_monitor, false); // Can also unlock methods.
1566 
1567   }
1568 
1569   // Reset active handles after returning from native.
1570   // thread->active_handles()->clear();
1571   __ ld(active_handles, thread_(active_handles));
1572   // TODO PPC port assert(4 == JNIHandleBlock::top_size_in_bytes(), "unexpected field size");
1573   __ li(R0, 0);
1574   __ stw(R0, JNIHandleBlock::top_offset_in_bytes(), active_handles);
1575 
1576   Label exception_return_sync_check_already_unlocked;
1577   __ ld(R0/*pending_exception*/, thread_(pending_exception));
1578   __ cmpdi(CCR0, R0/*pending_exception*/, 0);
1579   __ bne(CCR0, exception_return_sync_check_already_unlocked);
1580 
1581   //-----------------------------------------------------------------------------
1582   // No exception pending.
1583 
1584   // Move native method result back into proper registers and return.
1585   // Invoke result handler (may unbox/promote).
1586   __ ld(R11_scratch1, 0, R1_SP);
1587   __ ld(R3_RET, _ijava_state_neg(lresult), R11_scratch1);
1588   __ lfd(F1_RET, _ijava_state_neg(fresult), R11_scratch1);
1589   __ call_stub(result_handler_addr);
1590 
1591   __ merge_frames(/*top_frame_sp*/ R21_sender_SP, /*return_pc*/ R0, R11_scratch1, R12_scratch2);
1592 
1593   // Must use the return pc which was loaded from the caller's frame
1594   // as the VM uses return-pc-patching for deoptimization.
1595   __ mtlr(R0);
1596   __ blr();
1597 
1598   //-----------------------------------------------------------------------------
1599   // An exception is pending. We call into the runtime only if the
1600   // caller was not interpreted. If it was interpreted the
1601   // interpreter will do the correct thing. If it isn't interpreted
1602   // (call stub/compiled code) we will change our return and continue.
1603 
1604   BIND(exception_return_sync_check);
1605 
1606   if (synchronized) {
1607     // Don't check for exceptions since we're still in the i2n frame. Do that
1608     // manually afterwards.
1609     __ unlock_object(R26_monitor, false); // Can also unlock methods.
1610   }
1611   BIND(exception_return_sync_check_already_unlocked);
1612 
1613   const Register return_pc = R31;
1614 
1615   __ ld(return_pc, 0, R1_SP);
1616   __ ld(return_pc, _abi(lr), return_pc);
1617 
1618   // Get the address of the exception handler.
1619   __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::exception_handler_for_return_address),
1620                   R16_thread,
1621                   return_pc /* return pc */);
1622   __ merge_frames(/*top_frame_sp*/ R21_sender_SP, noreg, R11_scratch1, R12_scratch2);
1623 
1624   // Load the PC of the the exception handler into LR.
1625   __ mtlr(R3_RET);
1626 
1627   // Load exception into R3_ARG1 and clear pending exception in thread.
1628   __ ld(R3_ARG1/*exception*/, thread_(pending_exception));
1629   __ li(R4_ARG2, 0);
1630   __ std(R4_ARG2, thread_(pending_exception));
1631 
1632   // Load the original return pc into R4_ARG2.
1633   __ mr(R4_ARG2/*issuing_pc*/, return_pc);
1634 
1635   // Return to exception handler.
1636   __ blr();
1637 
1638   //=============================================================================
1639   // Counter overflow.
1640 
1641   if (inc_counter) {
1642     // Handle invocation counter overflow.
1643     __ bind(invocation_counter_overflow);
1644 
1645     generate_counter_overflow(continue_after_compile);
1646   }
1647 
1648   return entry;
1649 }
1650 
1651 // Generic interpreted method entry to (asm) interpreter.
1652 //
1653 address TemplateInterpreterGenerator::generate_normal_entry(bool synchronized) {
1654   bool inc_counter = UseCompiler || CountCompiledCalls || LogTouchedMethods;
1655   address entry = __ pc();
1656   // Generate the code to allocate the interpreter stack frame.
1657   Register Rsize_of_parameters = R4_ARG2, // Written by generate_fixed_frame.
1658            Rsize_of_locals     = R5_ARG3; // Written by generate_fixed_frame.
1659 
1660   // Does also a stack check to assure this frame fits on the stack.
1661   generate_fixed_frame(false, Rsize_of_parameters, Rsize_of_locals);
1662 
1663   // --------------------------------------------------------------------------
1664   // Zero out non-parameter locals.
1665   // Note: *Always* zero out non-parameter locals as Sparc does. It's not
1666   // worth to ask the flag, just do it.
1667   Register Rslot_addr = R6_ARG4,
1668            Rnum       = R7_ARG5;
1669   Label Lno_locals, Lzero_loop;
1670 
1671   // Set up the zeroing loop.
1672   __ subf(Rnum, Rsize_of_parameters, Rsize_of_locals);
1673   __ subf(Rslot_addr, Rsize_of_parameters, R18_locals);
1674   __ srdi_(Rnum, Rnum, Interpreter::logStackElementSize);
1675   __ beq(CCR0, Lno_locals);
1676   __ li(R0, 0);
1677   __ mtctr(Rnum);
1678 
1679   // The zero locals loop.
1680   __ bind(Lzero_loop);
1681   __ std(R0, 0, Rslot_addr);
1682   __ addi(Rslot_addr, Rslot_addr, -Interpreter::stackElementSize);
1683   __ bdnz(Lzero_loop);
1684 
1685   __ bind(Lno_locals);
1686 
1687   // --------------------------------------------------------------------------
1688   // Counter increment and overflow check.
1689   Label invocation_counter_overflow,
1690         profile_method,
1691         profile_method_continue;
1692   if (inc_counter || ProfileInterpreter) {
1693 
1694     Register Rdo_not_unlock_if_synchronized_addr = R11_scratch1;
1695     if (synchronized) {
1696       // Since at this point in the method invocation the exception handler
1697       // would try to exit the monitor of synchronized methods which hasn't
1698       // been entered yet, we set the thread local variable
1699       // _do_not_unlock_if_synchronized to true. If any exception was thrown by
1700       // runtime, exception handling i.e. unlock_if_synchronized_method will
1701       // check this thread local flag.
1702       // This flag has two effects, one is to force an unwind in the topmost
1703       // interpreter frame and not perform an unlock while doing so.
1704       __ li(R0, 1);
1705       __ stb(R0, in_bytes(JavaThread::do_not_unlock_if_synchronized_offset()), R16_thread);
1706     }
1707 
1708     // Argument and return type profiling.
1709     __ profile_parameters_type(R3_ARG1, R4_ARG2, R5_ARG3, R6_ARG4);
1710 
1711     // Increment invocation counter and check for overflow.
1712     if (inc_counter) {
1713       generate_counter_incr(&invocation_counter_overflow, &profile_method, &profile_method_continue);
1714     }
1715 
1716     __ bind(profile_method_continue);
1717   }
1718 
1719   bang_stack_shadow_pages(false);
1720 
1721   if (inc_counter || ProfileInterpreter) {
1722     // Reset the _do_not_unlock_if_synchronized flag.
1723     if (synchronized) {
1724       __ li(R0, 0);
1725       __ stb(R0, in_bytes(JavaThread::do_not_unlock_if_synchronized_offset()), R16_thread);
1726     }
1727   }
1728 
1729   // --------------------------------------------------------------------------
1730   // Locking of synchronized methods. Must happen AFTER invocation_counter
1731   // check and stack overflow check, so method is not locked if overflows.
1732   if (synchronized) {
1733     lock_method(R3_ARG1, R4_ARG2, R5_ARG3);
1734   }
1735 #ifdef ASSERT
1736   else {
1737     Label Lok;
1738     __ lwz(R0, in_bytes(Method::access_flags_offset()), R19_method);
1739     __ andi_(R0, R0, JVM_ACC_SYNCHRONIZED);
1740     __ asm_assert_eq("method needs synchronization", 0x8521);
1741     __ bind(Lok);
1742   }
1743 #endif // ASSERT
1744 
1745   __ verify_thread();
1746 
1747   // --------------------------------------------------------------------------
1748   // JVMTI support
1749   __ notify_method_entry();
1750 
1751   // --------------------------------------------------------------------------
1752   // Start executing instructions.
1753   __ dispatch_next(vtos);
1754 
1755   // --------------------------------------------------------------------------
1756   // Out of line counter overflow and MDO creation code.
1757   if (ProfileInterpreter) {
1758     // We have decided to profile this method in the interpreter.
1759     __ bind(profile_method);
1760     __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::profile_method));
1761     __ set_method_data_pointer_for_bcp();
1762     __ b(profile_method_continue);
1763   }
1764 
1765   if (inc_counter) {
1766     // Handle invocation counter overflow.
1767     __ bind(invocation_counter_overflow);
1768     generate_counter_overflow(profile_method_continue);
1769   }
1770   return entry;
1771 }
1772 
1773 // CRC32 Intrinsics.
1774 //
1775 // Contract on scratch and work registers.
1776 // =======================================
1777 //
1778 // On ppc, the register set {R2..R12} is available in the interpreter as scratch/work registers.
1779 // You should, however, keep in mind that {R3_ARG1..R10_ARG8} is the C-ABI argument register set.
1780 // You can't rely on these registers across calls.
1781 //
1782 // The generators for CRC32_update and for CRC32_updateBytes use the
1783 // scratch/work register set internally, passing the work registers
1784 // as arguments to the MacroAssembler emitters as required.
1785 //
1786 // R3_ARG1..R6_ARG4 are preset to hold the incoming java arguments.
1787 // Their contents is not constant but may change according to the requirements
1788 // of the emitted code.
1789 //
1790 // All other registers from the scratch/work register set are used "internally"
1791 // and contain garbage (i.e. unpredictable values) once blr() is reached.
1792 // Basically, only R3_RET contains a defined value which is the function result.
1793 //
1794 /**
1795  * Method entry for static native methods:
1796  *   int java.util.zip.CRC32.update(int crc, int b)
1797  */
1798 address TemplateInterpreterGenerator::generate_CRC32_update_entry() {
1799   if (UseCRC32Intrinsics) {
1800     address start = __ pc();  // Remember stub start address (is rtn value).
1801     Label slow_path;
1802 
1803     // Safepoint check
1804     const Register sync_state = R11_scratch1;
1805     int sync_state_offs = __ load_const_optimized(sync_state, SafepointSynchronize::address_of_state(), /*temp*/R0, true);
1806     __ lwz(sync_state, sync_state_offs, sync_state);
1807     __ cmpwi(CCR0, sync_state, SafepointSynchronize::_not_synchronized);
1808     __ bne(CCR0, slow_path);
1809 
1810     // We don't generate local frame and don't align stack because
1811     // we not even call stub code (we generate the code inline)
1812     // and there is no safepoint on this path.
1813 
1814     // Load java parameters.
1815     // R15_esp is callers operand stack pointer, i.e. it points to the parameters.
1816     const Register argP    = R15_esp;
1817     const Register crc     = R3_ARG1;  // crc value
1818     const Register data    = R4_ARG2;  // address of java byte value (kernel_crc32 needs address)
1819     const Register dataLen = R5_ARG3;  // source data len (1 byte). Not used because calling the single-byte emitter.
1820     const Register table   = R6_ARG4;  // address of crc32 table
1821     const Register tmp     = dataLen;  // Reuse unused len register to show we don't actually need a separate tmp here.
1822 
1823     BLOCK_COMMENT("CRC32_update {");
1824 
1825     // Arguments are reversed on java expression stack
1826 #ifdef VM_LITTLE_ENDIAN
1827     __ addi(data, argP, 0+1*wordSize); // (stack) address of byte value. Emitter expects address, not value.
1828                                        // Being passed as an int, the single byte is at offset +0.
1829 #else
1830     __ addi(data, argP, 3+1*wordSize); // (stack) address of byte value. Emitter expects address, not value.
1831                                        // Being passed from java as an int, the single byte is at offset +3.
1832 #endif
1833     __ lwz(crc,  2*wordSize, argP);    // Current crc state, zero extend to 64 bit to have a clean register.
1834 
1835     StubRoutines::ppc64::generate_load_crc_table_addr(_masm, table);
1836     __ kernel_crc32_singleByte(crc, data, dataLen, table, tmp);
1837 
1838     // Restore caller sp for c2i case and return.
1839     __ mr(R1_SP, R21_sender_SP); // Cut the stack back to where the caller started.
1840     __ blr();
1841 
1842     // Generate a vanilla native entry as the slow path.
1843     BLOCK_COMMENT("} CRC32_update");
1844     BIND(slow_path);
1845     __ jump_to_entry(Interpreter::entry_for_kind(Interpreter::native), R11_scratch1);
1846     return start;
1847   }
1848 
1849   return NULL;
1850 }
1851 
1852 // CRC32 Intrinsics.
1853 /**
1854  * Method entry for static native methods:
1855  *   int java.util.zip.CRC32.updateBytes(     int crc, byte[] b,  int off, int len)
1856  *   int java.util.zip.CRC32.updateByteBuffer(int crc, long* buf, int off, int len)
1857  */
1858 address TemplateInterpreterGenerator::generate_CRC32_updateBytes_entry(AbstractInterpreter::MethodKind kind) {
1859   if (UseCRC32Intrinsics) {
1860     address start = __ pc();  // Remember stub start address (is rtn value).
1861     Label slow_path;
1862 
1863     // Safepoint check
1864     const Register sync_state = R11_scratch1;
1865     int sync_state_offs = __ load_const_optimized(sync_state, SafepointSynchronize::address_of_state(), /*temp*/R0, true);
1866     __ lwz(sync_state, sync_state_offs, sync_state);
1867     __ cmpwi(CCR0, sync_state, SafepointSynchronize::_not_synchronized);
1868     __ bne(CCR0, slow_path);
1869 
1870     // We don't generate local frame and don't align stack because
1871     // we not even call stub code (we generate the code inline)
1872     // and there is no safepoint on this path.
1873 
1874     // Load parameters.
1875     // Z_esp is callers operand stack pointer, i.e. it points to the parameters.
1876     const Register argP    = R15_esp;
1877     const Register crc     = R3_ARG1;  // crc value
1878     const Register data    = R4_ARG2;  // address of java byte array
1879     const Register dataLen = R5_ARG3;  // source data len
1880     const Register table   = R6_ARG4;  // address of crc32 table
1881 
1882     const Register t0      = R9;       // scratch registers for crc calculation
1883     const Register t1      = R10;
1884     const Register t2      = R11;
1885     const Register t3      = R12;
1886 
1887     const Register tc0     = R2;       // registers to hold pre-calculated column addresses
1888     const Register tc1     = R7;
1889     const Register tc2     = R8;
1890     const Register tc3     = table;    // table address is reconstructed at the end of kernel_crc32_* emitters
1891 
1892     const Register tmp     = t0;       // Only used very locally to calculate byte buffer address.
1893 
1894     // Arguments are reversed on java expression stack.
1895     // Calculate address of start element.
1896     if (kind == Interpreter::java_util_zip_CRC32_updateByteBuffer) { // Used for "updateByteBuffer direct".
1897       BLOCK_COMMENT("CRC32_updateByteBuffer {");
1898       // crc     @ (SP + 5W) (32bit)
1899       // buf     @ (SP + 3W) (64bit ptr to long array)
1900       // off     @ (SP + 2W) (32bit)
1901       // dataLen @ (SP + 1W) (32bit)
1902       // data = buf + off
1903       __ ld(  data,    3*wordSize, argP);  // start of byte buffer
1904       __ lwa( tmp,     2*wordSize, argP);  // byte buffer offset
1905       __ lwa( dataLen, 1*wordSize, argP);  // #bytes to process
1906       __ lwz( crc,     5*wordSize, argP);  // current crc state
1907       __ add( data, data, tmp);            // Add byte buffer offset.
1908     } else {                                                         // Used for "updateBytes update".
1909       BLOCK_COMMENT("CRC32_updateBytes {");
1910       // crc     @ (SP + 4W) (32bit)
1911       // buf     @ (SP + 3W) (64bit ptr to byte array)
1912       // off     @ (SP + 2W) (32bit)
1913       // dataLen @ (SP + 1W) (32bit)
1914       // data = buf + off + base_offset
1915       __ ld(  data,    3*wordSize, argP);  // start of byte buffer
1916       __ lwa( tmp,     2*wordSize, argP);  // byte buffer offset
1917       __ lwa( dataLen, 1*wordSize, argP);  // #bytes to process
1918       __ add( data, data, tmp);            // add byte buffer offset
1919       __ lwz( crc,     4*wordSize, argP);  // current crc state
1920       __ addi(data, data, arrayOopDesc::base_offset_in_bytes(T_BYTE));
1921     }
1922 
1923     StubRoutines::ppc64::generate_load_crc_table_addr(_masm, table);
1924 
1925     // Performance measurements show the 1word and 2word variants to be almost equivalent,
1926     // with very light advantages for the 1word variant. We chose the 1word variant for
1927     // code compactness.
1928     __ kernel_crc32_1word(crc, data, dataLen, table, t0, t1, t2, t3, tc0, tc1, tc2, tc3);
1929 
1930     // Restore caller sp for c2i case and return.
1931     __ mr(R1_SP, R21_sender_SP); // Cut the stack back to where the caller started.
1932     __ blr();
1933 
1934     // Generate a vanilla native entry as the slow path.
1935     BLOCK_COMMENT("} CRC32_updateBytes(Buffer)");
1936     BIND(slow_path);
1937     __ jump_to_entry(Interpreter::entry_for_kind(Interpreter::native), R11_scratch1);
1938     return start;
1939   }
1940 
1941   return NULL;
1942 }
1943 
1944 // Not supported
1945 address TemplateInterpreterGenerator::generate_CRC32C_updateBytes_entry(AbstractInterpreter::MethodKind kind) {
1946   return NULL;
1947 }
1948 
1949 // =============================================================================
1950 // Exceptions
1951 
1952 void TemplateInterpreterGenerator::generate_throw_exception() {
1953   Register Rexception    = R17_tos,
1954            Rcontinuation = R3_RET;
1955 
1956   // --------------------------------------------------------------------------
1957   // Entry point if an method returns with a pending exception (rethrow).
1958   Interpreter::_rethrow_exception_entry = __ pc();
1959   {
1960     __ restore_interpreter_state(R11_scratch1); // Sets R11_scratch1 = fp.
1961     __ ld(R12_scratch2, _ijava_state_neg(top_frame_sp), R11_scratch1);
1962     __ resize_frame_absolute(R12_scratch2, R11_scratch1, R0);
1963 
1964     // Compiled code destroys templateTableBase, reload.
1965     __ load_const_optimized(R25_templateTableBase, (address)Interpreter::dispatch_table((TosState)0), R11_scratch1);
1966   }
1967 
1968   // Entry point if a interpreted method throws an exception (throw).
1969   Interpreter::_throw_exception_entry = __ pc();
1970   {
1971     __ mr(Rexception, R3_RET);
1972 
1973     __ verify_thread();
1974     __ verify_oop(Rexception);
1975 
1976     // Expression stack must be empty before entering the VM in case of an exception.
1977     __ empty_expression_stack();
1978     // Find exception handler address and preserve exception oop.
1979     // Call C routine to find handler and jump to it.
1980     __ call_VM(Rexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::exception_handler_for_exception), Rexception);
1981     __ mtctr(Rcontinuation);
1982     // Push exception for exception handler bytecodes.
1983     __ push_ptr(Rexception);
1984 
1985     // Jump to exception handler (may be remove activation entry!).
1986     __ bctr();
1987   }
1988 
1989   // If the exception is not handled in the current frame the frame is
1990   // removed and the exception is rethrown (i.e. exception
1991   // continuation is _rethrow_exception).
1992   //
1993   // Note: At this point the bci is still the bxi for the instruction
1994   // which caused the exception and the expression stack is
1995   // empty. Thus, for any VM calls at this point, GC will find a legal
1996   // oop map (with empty expression stack).
1997 
1998   // In current activation
1999   // tos: exception
2000   // bcp: exception bcp
2001 
2002   // --------------------------------------------------------------------------
2003   // JVMTI PopFrame support
2004 
2005   Interpreter::_remove_activation_preserving_args_entry = __ pc();
2006   {
2007     // Set the popframe_processing bit in popframe_condition indicating that we are
2008     // currently handling popframe, so that call_VMs that may happen later do not
2009     // trigger new popframe handling cycles.
2010     __ lwz(R11_scratch1, in_bytes(JavaThread::popframe_condition_offset()), R16_thread);
2011     __ ori(R11_scratch1, R11_scratch1, JavaThread::popframe_processing_bit);
2012     __ stw(R11_scratch1, in_bytes(JavaThread::popframe_condition_offset()), R16_thread);
2013 
2014     // Empty the expression stack, as in normal exception handling.
2015     __ empty_expression_stack();
2016     __ unlock_if_synchronized_method(vtos, /* throw_monitor_exception */ false, /* install_monitor_exception */ false);
2017 
2018     // Check to see whether we are returning to a deoptimized frame.
2019     // (The PopFrame call ensures that the caller of the popped frame is
2020     // either interpreted or compiled and deoptimizes it if compiled.)
2021     // Note that we don't compare the return PC against the
2022     // deoptimization blob's unpack entry because of the presence of
2023     // adapter frames in C2.
2024     Label Lcaller_not_deoptimized;
2025     Register return_pc = R3_ARG1;
2026     __ ld(return_pc, 0, R1_SP);
2027     __ ld(return_pc, _abi(lr), return_pc);
2028     __ call_VM_leaf(CAST_FROM_FN_PTR(address, InterpreterRuntime::interpreter_contains), return_pc);
2029     __ cmpdi(CCR0, R3_RET, 0);
2030     __ bne(CCR0, Lcaller_not_deoptimized);
2031 
2032     // The deoptimized case.
2033     // In this case, we can't call dispatch_next() after the frame is
2034     // popped, but instead must save the incoming arguments and restore
2035     // them after deoptimization has occurred.
2036     __ ld(R4_ARG2, in_bytes(Method::const_offset()), R19_method);
2037     __ lhz(R4_ARG2 /* number of params */, in_bytes(ConstMethod::size_of_parameters_offset()), R4_ARG2);
2038     __ slwi(R4_ARG2, R4_ARG2, Interpreter::logStackElementSize);
2039     __ addi(R5_ARG3, R18_locals, Interpreter::stackElementSize);
2040     __ subf(R5_ARG3, R4_ARG2, R5_ARG3);
2041     // Save these arguments.
2042     __ call_VM_leaf(CAST_FROM_FN_PTR(address, Deoptimization::popframe_preserve_args), R16_thread, R4_ARG2, R5_ARG3);
2043 
2044     // Inform deoptimization that it is responsible for restoring these arguments.
2045     __ load_const_optimized(R11_scratch1, JavaThread::popframe_force_deopt_reexecution_bit);
2046     __ stw(R11_scratch1, in_bytes(JavaThread::popframe_condition_offset()), R16_thread);
2047 
2048     // Return from the current method into the deoptimization blob. Will eventually
2049     // end up in the deopt interpeter entry, deoptimization prepared everything that
2050     // we will reexecute the call that called us.
2051     __ merge_frames(/*top_frame_sp*/ R21_sender_SP, /*reload return_pc*/ return_pc, R11_scratch1, R12_scratch2);
2052     __ mtlr(return_pc);
2053     __ blr();
2054 
2055     // The non-deoptimized case.
2056     __ bind(Lcaller_not_deoptimized);
2057 
2058     // Clear the popframe condition flag.
2059     __ li(R0, 0);
2060     __ stw(R0, in_bytes(JavaThread::popframe_condition_offset()), R16_thread);
2061 
2062     // Get out of the current method and re-execute the call that called us.
2063     __ merge_frames(/*top_frame_sp*/ R21_sender_SP, /*return_pc*/ noreg, R11_scratch1, R12_scratch2);
2064     __ restore_interpreter_state(R11_scratch1);
2065     __ ld(R12_scratch2, _ijava_state_neg(top_frame_sp), R11_scratch1);
2066     __ resize_frame_absolute(R12_scratch2, R11_scratch1, R0);
2067     if (ProfileInterpreter) {
2068       __ set_method_data_pointer_for_bcp();
2069       __ ld(R11_scratch1, 0, R1_SP);
2070       __ std(R28_mdx, _ijava_state_neg(mdx), R11_scratch1);
2071     }
2072 #if INCLUDE_JVMTI
2073     Label L_done;
2074 
2075     __ lbz(R11_scratch1, 0, R14_bcp);
2076     __ cmpwi(CCR0, R11_scratch1, Bytecodes::_invokestatic);
2077     __ bne(CCR0, L_done);
2078 
2079     // The member name argument must be restored if _invokestatic is re-executed after a PopFrame call.
2080     // Detect such a case in the InterpreterRuntime function and return the member name argument, or NULL.
2081     __ ld(R4_ARG2, 0, R18_locals);
2082     __ MacroAssembler::call_VM(R4_ARG2, CAST_FROM_FN_PTR(address, InterpreterRuntime::member_name_arg_or_null), R4_ARG2, R19_method, R14_bcp, false);
2083     __ restore_interpreter_state(R11_scratch1, /*bcp_and_mdx_only*/ true);
2084     __ cmpdi(CCR0, R4_ARG2, 0);
2085     __ beq(CCR0, L_done);
2086     __ std(R4_ARG2, wordSize, R15_esp);
2087     __ bind(L_done);
2088 #endif // INCLUDE_JVMTI
2089     __ dispatch_next(vtos);
2090   }
2091   // end of JVMTI PopFrame support
2092 
2093   // --------------------------------------------------------------------------
2094   // Remove activation exception entry.
2095   // This is jumped to if an interpreted method can't handle an exception itself
2096   // (we come from the throw/rethrow exception entry above). We're going to call
2097   // into the VM to find the exception handler in the caller, pop the current
2098   // frame and return the handler we calculated.
2099   Interpreter::_remove_activation_entry = __ pc();
2100   {
2101     __ pop_ptr(Rexception);
2102     __ verify_thread();
2103     __ verify_oop(Rexception);
2104     __ std(Rexception, in_bytes(JavaThread::vm_result_offset()), R16_thread);
2105 
2106     __ unlock_if_synchronized_method(vtos, /* throw_monitor_exception */ false, true);
2107     __ notify_method_exit(false, vtos, InterpreterMacroAssembler::SkipNotifyJVMTI, false);
2108 
2109     __ get_vm_result(Rexception);
2110 
2111     // We are done with this activation frame; find out where to go next.
2112     // The continuation point will be an exception handler, which expects
2113     // the following registers set up:
2114     //
2115     // RET:  exception oop
2116     // ARG2: Issuing PC (see generate_exception_blob()), only used if the caller is compiled.
2117 
2118     Register return_pc = R31; // Needs to survive the runtime call.
2119     __ ld(return_pc, 0, R1_SP);
2120     __ ld(return_pc, _abi(lr), return_pc);
2121     __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::exception_handler_for_return_address), R16_thread, return_pc);
2122 
2123     // Remove the current activation.
2124     __ merge_frames(/*top_frame_sp*/ R21_sender_SP, /*return_pc*/ noreg, R11_scratch1, R12_scratch2);
2125 
2126     __ mr(R4_ARG2, return_pc);
2127     __ mtlr(R3_RET);
2128     __ mr(R3_RET, Rexception);
2129     __ blr();
2130   }
2131 }
2132 
2133 // JVMTI ForceEarlyReturn support.
2134 // Returns "in the middle" of a method with a "fake" return value.
2135 address TemplateInterpreterGenerator::generate_earlyret_entry_for(TosState state) {
2136 
2137   Register Rscratch1 = R11_scratch1,
2138            Rscratch2 = R12_scratch2;
2139 
2140   address entry = __ pc();
2141   __ empty_expression_stack();
2142 
2143   __ load_earlyret_value(state, Rscratch1);
2144 
2145   __ ld(Rscratch1, in_bytes(JavaThread::jvmti_thread_state_offset()), R16_thread);
2146   // Clear the earlyret state.
2147   __ li(R0, 0);
2148   __ stw(R0, in_bytes(JvmtiThreadState::earlyret_state_offset()), Rscratch1);
2149 
2150   __ remove_activation(state, false, false);
2151   // Copied from TemplateTable::_return.
2152   // Restoration of lr done by remove_activation.
2153   switch (state) {
2154     // Narrow result if state is itos but result type is smaller.
2155     case itos: __ narrow(R17_tos); /* fall through */
2156     case ltos:
2157     case btos:
2158     case ztos:
2159     case ctos:
2160     case stos:
2161     case atos: __ mr(R3_RET, R17_tos); break;
2162     case ftos:
2163     case dtos: __ fmr(F1_RET, F15_ftos); break;
2164     case vtos: // This might be a constructor. Final fields (and volatile fields on PPC64) need
2165                // to get visible before the reference to the object gets stored anywhere.
2166                __ membar(Assembler::StoreStore); break;
2167     default  : ShouldNotReachHere();
2168   }
2169   __ blr();
2170 
2171   return entry;
2172 } // end of ForceEarlyReturn support
2173 
2174 //-----------------------------------------------------------------------------
2175 // Helper for vtos entry point generation
2176 
2177 void TemplateInterpreterGenerator::set_vtos_entry_points(Template* t,
2178                                                          address& bep,
2179                                                          address& cep,
2180                                                          address& sep,
2181                                                          address& aep,
2182                                                          address& iep,
2183                                                          address& lep,
2184                                                          address& fep,
2185                                                          address& dep,
2186                                                          address& vep) {
2187   assert(t->is_valid() && t->tos_in() == vtos, "illegal template");
2188   Label L;
2189 
2190   aep = __ pc();  __ push_ptr();  __ b(L);
2191   fep = __ pc();  __ push_f();    __ b(L);
2192   dep = __ pc();  __ push_d();    __ b(L);
2193   lep = __ pc();  __ push_l();    __ b(L);
2194   __ align(32, 12, 24); // align L
2195   bep = cep = sep =
2196   iep = __ pc();  __ push_i();
2197   vep = __ pc();
2198   __ bind(L);
2199   generate_and_dispatch(t);
2200 }
2201 
2202 //-----------------------------------------------------------------------------
2203 
2204 // Non-product code
2205 #ifndef PRODUCT
2206 address TemplateInterpreterGenerator::generate_trace_code(TosState state) {
2207   //__ flush_bundle();
2208   address entry = __ pc();
2209 
2210   const char *bname = NULL;
2211   uint tsize = 0;
2212   switch(state) {
2213   case ftos:
2214     bname = "trace_code_ftos {";
2215     tsize = 2;
2216     break;
2217   case btos:
2218     bname = "trace_code_btos {";
2219     tsize = 2;
2220     break;
2221   case ztos:
2222     bname = "trace_code_ztos {";
2223     tsize = 2;
2224     break;
2225   case ctos:
2226     bname = "trace_code_ctos {";
2227     tsize = 2;
2228     break;
2229   case stos:
2230     bname = "trace_code_stos {";
2231     tsize = 2;
2232     break;
2233   case itos:
2234     bname = "trace_code_itos {";
2235     tsize = 2;
2236     break;
2237   case ltos:
2238     bname = "trace_code_ltos {";
2239     tsize = 3;
2240     break;
2241   case atos:
2242     bname = "trace_code_atos {";
2243     tsize = 2;
2244     break;
2245   case vtos:
2246     // Note: In case of vtos, the topmost of stack value could be a int or doubl
2247     // In case of a double (2 slots) we won't see the 2nd stack value.
2248     // Maybe we simply should print the topmost 3 stack slots to cope with the problem.
2249     bname = "trace_code_vtos {";
2250     tsize = 2;
2251 
2252     break;
2253   case dtos:
2254     bname = "trace_code_dtos {";
2255     tsize = 3;
2256     break;
2257   default:
2258     ShouldNotReachHere();
2259   }
2260   BLOCK_COMMENT(bname);
2261 
2262   // Support short-cut for TraceBytecodesAt.
2263   // Don't call into the VM if we don't want to trace to speed up things.
2264   Label Lskip_vm_call;
2265   if (TraceBytecodesAt > 0 && TraceBytecodesAt < max_intx) {
2266     int offs1 = __ load_const_optimized(R11_scratch1, (address) &TraceBytecodesAt, R0, true);
2267     int offs2 = __ load_const_optimized(R12_scratch2, (address) &BytecodeCounter::_counter_value, R0, true);
2268     __ ld(R11_scratch1, offs1, R11_scratch1);
2269     __ lwa(R12_scratch2, offs2, R12_scratch2);
2270     __ cmpd(CCR0, R12_scratch2, R11_scratch1);
2271     __ blt(CCR0, Lskip_vm_call);
2272   }
2273 
2274   __ push(state);
2275   // Load 2 topmost expression stack values.
2276   __ ld(R6_ARG4, tsize*Interpreter::stackElementSize, R15_esp);
2277   __ ld(R5_ARG3, Interpreter::stackElementSize, R15_esp);
2278   __ mflr(R31);
2279   __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::trace_bytecode), /* unused */ R4_ARG2, R5_ARG3, R6_ARG4, false);
2280   __ mtlr(R31);
2281   __ pop(state);
2282 
2283   if (TraceBytecodesAt > 0 && TraceBytecodesAt < max_intx) {
2284     __ bind(Lskip_vm_call);
2285   }
2286   __ blr();
2287   BLOCK_COMMENT("} trace_code");
2288   return entry;
2289 }
2290 
2291 void TemplateInterpreterGenerator::count_bytecode() {
2292   int offs = __ load_const_optimized(R11_scratch1, (address) &BytecodeCounter::_counter_value, R12_scratch2, true);
2293   __ lwz(R12_scratch2, offs, R11_scratch1);
2294   __ addi(R12_scratch2, R12_scratch2, 1);
2295   __ stw(R12_scratch2, offs, R11_scratch1);
2296 }
2297 
2298 void TemplateInterpreterGenerator::histogram_bytecode(Template* t) {
2299   int offs = __ load_const_optimized(R11_scratch1, (address) &BytecodeHistogram::_counters[t->bytecode()], R12_scratch2, true);
2300   __ lwz(R12_scratch2, offs, R11_scratch1);
2301   __ addi(R12_scratch2, R12_scratch2, 1);
2302   __ stw(R12_scratch2, offs, R11_scratch1);
2303 }
2304 
2305 void TemplateInterpreterGenerator::histogram_bytecode_pair(Template* t) {
2306   const Register addr = R11_scratch1,
2307                  tmp  = R12_scratch2;
2308   // Get index, shift out old bytecode, bring in new bytecode, and store it.
2309   // _index = (_index >> log2_number_of_codes) |
2310   //          (bytecode << log2_number_of_codes);
2311   int offs1 = __ load_const_optimized(addr, (address)&BytecodePairHistogram::_index, tmp, true);
2312   __ lwz(tmp, offs1, addr);
2313   __ srwi(tmp, tmp, BytecodePairHistogram::log2_number_of_codes);
2314   __ ori(tmp, tmp, ((int) t->bytecode()) << BytecodePairHistogram::log2_number_of_codes);
2315   __ stw(tmp, offs1, addr);
2316 
2317   // Bump bucket contents.
2318   // _counters[_index] ++;
2319   int offs2 = __ load_const_optimized(addr, (address)&BytecodePairHistogram::_counters, R0, true);
2320   __ sldi(tmp, tmp, LogBytesPerInt);
2321   __ add(addr, tmp, addr);
2322   __ lwz(tmp, offs2, addr);
2323   __ addi(tmp, tmp, 1);
2324   __ stw(tmp, offs2, addr);
2325 }
2326 
2327 void TemplateInterpreterGenerator::trace_bytecode(Template* t) {
2328   // Call a little run-time stub to avoid blow-up for each bytecode.
2329   // The run-time runtime saves the right registers, depending on
2330   // the tosca in-state for the given template.
2331 
2332   assert(Interpreter::trace_code(t->tos_in()) != NULL,
2333          "entry must have been generated");
2334 
2335   // Note: we destroy LR here.
2336   __ bl(Interpreter::trace_code(t->tos_in()));
2337 }
2338 
2339 void TemplateInterpreterGenerator::stop_interpreter_at() {
2340   Label L;
2341   int offs1 = __ load_const_optimized(R11_scratch1, (address) &StopInterpreterAt, R0, true);
2342   int offs2 = __ load_const_optimized(R12_scratch2, (address) &BytecodeCounter::_counter_value, R0, true);
2343   __ ld(R11_scratch1, offs1, R11_scratch1);
2344   __ lwa(R12_scratch2, offs2, R12_scratch2);
2345   __ cmpd(CCR0, R12_scratch2, R11_scratch1);
2346   __ bne(CCR0, L);
2347   __ illtrap();
2348   __ bind(L);
2349 }
2350 
2351 #endif // !PRODUCT