Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  *

  */

 /*

  * This file has been modified by Loongson Technology in 2015. These

  * modifications are Copyright (c) 2015 Loongson Technology, and are made

  * available on the same license terms set forth above.

  */

 #include "precompiled.hpp"

 #include "classfile/systemDictionary.hpp"

 #include "classfile/vmSymbols.hpp"

 #include "code/compiledIC.hpp"

 #include "code/scopeDesc.hpp"

 #include "code/vtableStubs.hpp"

 #include "compiler/abstractCompiler.hpp"

 #include "compiler/compileBroker.hpp"

 #include "compiler/compilerOracle.hpp"

 #include "compiler/disassembler.hpp"

 #include "interpreter/interpreter.hpp"

 #include "interpreter/interpreterRuntime.hpp"

 #include "memory/gcLocker.inline.hpp"

 #include "memory/universe.inline.hpp"

 #include "oops/oop.inline.hpp"

 #include "prims/forte.hpp"

 #include "prims/jvmtiExport.hpp"

 #include "prims/jvmtiRedefineClassesTrace.hpp"

 #include "prims/methodHandles.hpp"

 #include "prims/nativeLookup.hpp"

 #include "runtime/arguments.hpp"

 #include "runtime/biasedLocking.hpp"

 #include "runtime/handles.inline.hpp"

 #include "runtime/init.hpp"

 #include "runtime/interfaceSupport.hpp"

 #include "runtime/javaCalls.hpp"

 #include "runtime/sharedRuntime.hpp"

 #include "runtime/stubRoutines.hpp"

 #include "runtime/vframe.hpp"

 #include "runtime/vframeArray.hpp"

 #include "utilities/copy.hpp"

 #include "utilities/dtrace.hpp"

 #include "utilities/events.hpp"

 #include "utilities/hashtable.inline.hpp"

 #include "utilities/macros.hpp"

 #include "utilities/xmlstream.hpp"

 #ifdef TARGET_ARCH_x86

 # include "nativeInst_x86.hpp"

 # include "vmreg_x86.inline.hpp"

 #endif

 #ifdef TARGET_ARCH_sparc

 # include "nativeInst_sparc.hpp"

 # include "vmreg_sparc.inline.hpp"

 #endif

 #ifdef TARGET_ARCH_zero

 # include "nativeInst_zero.hpp"

 # include "vmreg_zero.inline.hpp"

 #endif

 #ifdef TARGET_ARCH_arm

 # include "nativeInst_arm.hpp"

 # include "vmreg_arm.inline.hpp"

 #endif

 #ifdef TARGET_ARCH_ppc

 # include "nativeInst_ppc.hpp"

 # include "vmreg_ppc.inline.hpp"

 #endif

 #ifdef TARGET_ARCH_mips

 # include "nativeInst_mips.hpp"

 # include "vmreg_mips.inline.hpp"

 #endif

 #ifdef COMPILER1

 #include "c1/c1_Runtime1.hpp"

 #endif

 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC

 // Shared stub locations

 RuntimeStub*        SharedRuntime::_wrong_method_blob;

 RuntimeStub*        SharedRuntime::_wrong_method_abstract_blob;

 RuntimeStub*        SharedRuntime::_ic_miss_blob;

 RuntimeStub*        SharedRuntime::_resolve_opt_virtual_call_blob;

 RuntimeStub*        SharedRuntime::_resolve_virtual_call_blob;

 RuntimeStub*        SharedRuntime::_resolve_static_call_blob;

 DeoptimizationBlob* SharedRuntime::_deopt_blob;

 SafepointBlob*      SharedRuntime::_polling_page_vectors_safepoint_handler_blob;

 SafepointBlob*      SharedRuntime::_polling_page_safepoint_handler_blob;

 SafepointBlob*      SharedRuntime::_polling_page_return_handler_blob;

 #ifdef COMPILER2

 UncommonTrapBlob*   SharedRuntime::_uncommon_trap_blob;

 #endif // COMPILER2

 //----------------------------generate_stubs-----------------------------------

 void SharedRuntime::generate_stubs() {

   _wrong_method_blob                   = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method),          "wrong_method_stub");

   _wrong_method_abstract_blob          = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method_abstract), "wrong_method_abstract_stub");

   _ic_miss_blob                        = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method_ic_miss),  "ic_miss_stub");

   _resolve_opt_virtual_call_blob       = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_opt_virtual_call_C),   "resolve_opt_virtual_call");

   _resolve_virtual_call_blob           = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_virtual_call_C),       "resolve_virtual_call");

   _resolve_static_call_blob            = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_static_call_C),        "resolve_static_call");

 #ifdef COMPILER2

   // Vectors are generated only by C2.

   if (is_wide_vector(MaxVectorSize)) {

     _polling_page_vectors_safepoint_handler_blob = generate_handler_blob(CAST_FROM_FN_PTR(address, SafepointSynchronize::handle_polling_page_exception), POLL_AT_VECTOR_LOOP);

   }

 #endif // COMPILER2

   _polling_page_safepoint_handler_blob = generate_handler_blob(CAST_FROM_FN_PTR(address, SafepointSynchronize::handle_polling_page_exception), POLL_AT_LOOP);

   _polling_page_return_handler_blob    = generate_handler_blob(CAST_FROM_FN_PTR(address, SafepointSynchronize::handle_polling_page_exception), POLL_AT_RETURN);

   generate_deopt_blob();

 #ifdef COMPILER2

   generate_uncommon_trap_blob();

 #endif // COMPILER2

 }

 #include <math.h>

 #ifndef USDT2

 HS_DTRACE_PROBE_DECL4(hotspot, object__alloc, Thread*, char*, int, size_t);

 HS_DTRACE_PROBE_DECL7(hotspot, method__entry, int,

                       char*, int, char*, int, char*, int);

 HS_DTRACE_PROBE_DECL7(hotspot, method__return, int,

                       char*, int, char*, int, char*, int);

 #endif /* !USDT2 */

 // Implementation of SharedRuntime

 #ifndef PRODUCT

 // For statistics

 int SharedRuntime::_ic_miss_ctr = 0;

 int SharedRuntime::_wrong_method_ctr = 0;

 int SharedRuntime::_resolve_static_ctr = 0;

 int SharedRuntime::_resolve_virtual_ctr = 0;

 int SharedRuntime::_resolve_opt_virtual_ctr = 0;

 int SharedRuntime::_implicit_null_throws = 0;

 int SharedRuntime::_implicit_div0_throws = 0;

 int SharedRuntime::_throw_null_ctr = 0;

 int SharedRuntime::_nof_normal_calls = 0;

 int SharedRuntime::_nof_optimized_calls = 0;

 int SharedRuntime::_nof_inlined_calls = 0;

 int SharedRuntime::_nof_megamorphic_calls = 0;

 int SharedRuntime::_nof_static_calls = 0;

 int SharedRuntime::_nof_inlined_static_calls = 0;

 int SharedRuntime::_nof_interface_calls = 0;

 int SharedRuntime::_nof_optimized_interface_calls = 0;

 int SharedRuntime::_nof_inlined_interface_calls = 0;

 int SharedRuntime::_nof_megamorphic_interface_calls = 0;

 int SharedRuntime::_nof_removable_exceptions = 0;

 int SharedRuntime::_new_instance_ctr=0;

 int SharedRuntime::_new_array_ctr=0;

 int SharedRuntime::_multi1_ctr=0;

 int SharedRuntime::_multi2_ctr=0;

 int SharedRuntime::_multi3_ctr=0;

 int SharedRuntime::_multi4_ctr=0;

 int SharedRuntime::_multi5_ctr=0;

 int SharedRuntime::_mon_enter_stub_ctr=0;

 int SharedRuntime::_mon_exit_stub_ctr=0;

 int SharedRuntime::_mon_enter_ctr=0;

 int SharedRuntime::_mon_exit_ctr=0;

 int SharedRuntime::_partial_subtype_ctr=0;

 int SharedRuntime::_jbyte_array_copy_ctr=0;

 int SharedRuntime::_jshort_array_copy_ctr=0;

 int SharedRuntime::_jint_array_copy_ctr=0;

 int SharedRuntime::_jlong_array_copy_ctr=0;

 int SharedRuntime::_oop_array_copy_ctr=0;

 int SharedRuntime::_checkcast_array_copy_ctr=0;

 int SharedRuntime::_unsafe_array_copy_ctr=0;

 int SharedRuntime::_generic_array_copy_ctr=0;

 int SharedRuntime::_slow_array_copy_ctr=0;

 int SharedRuntime::_find_handler_ctr=0;

 int SharedRuntime::_rethrow_ctr=0;

 int     SharedRuntime::_ICmiss_index                    = 0;

 int     SharedRuntime::_ICmiss_count[SharedRuntime::maxICmiss_count];

 address SharedRuntime::_ICmiss_at[SharedRuntime::maxICmiss_count];

 void SharedRuntime::trace_ic_miss(address at) {

   for (int i = 0; i < _ICmiss_index; i++) {

     if (_ICmiss_at[i] == at) {

       _ICmiss_count[i]++;

       return;

     }

   }

   int index = _ICmiss_index++;

   if (_ICmiss_index >= maxICmiss_count) _ICmiss_index = maxICmiss_count - 1;

   _ICmiss_at[index] = at;

   _ICmiss_count[index] = 1;

 }

 void SharedRuntime::print_ic_miss_histogram() {

   if (ICMissHistogram) {

     tty->print_cr ("IC Miss Histogram:");

     int tot_misses = 0;

     for (int i = 0; i < _ICmiss_index; i++) {

       tty->print_cr("  at: " INTPTR_FORMAT "  nof: %d", _ICmiss_at[i], _ICmiss_count[i]);

       tot_misses += _ICmiss_count[i];

     }

     tty->print_cr ("Total IC misses: %7d", tot_misses);

   }

 }

 #endif // PRODUCT

 void SharedRuntime::print_long(long long i) {

   tty->print("%llx", i);

 }

 void SharedRuntime::print_int(int i) {

   tty->print("%x", i);

 }

 void SharedRuntime::print_float(float f) {

   tty->print("ld:%ld ", f);

   tty->print("lx:%lx ", f);

   tty->print("lf:%g ", f);

 }

 void SharedRuntime::print_double(double f) {

   tty->print("%ld ", f);

   tty->print("0x%lx ", f);

   tty->print("%g ", f);

 }

 void SharedRuntime::print_str(char *str) {

   tty->print("%s", str);

 }

 void SharedRuntime::print_reg_with_pc(char *reg_name, long i, long pc) {

   tty->print_cr("%s: %lx pc: %lx", reg_name, i, pc);

 }

 #if INCLUDE_ALL_GCS

 // G1 write-barrier pre: executed before a pointer store.

 JRT_LEAF(void, SharedRuntime::g1_wb_pre(oopDesc* orig, JavaThread *thread))

   if (orig == NULL) {

     assert(false, "should be optimized out");

     return;

   }

   assert(orig->is_oop(true /* ignore mark word */), "Error");

   // store the original value that was in the field reference

   thread->satb_mark_queue().enqueue(orig);

 JRT_END

 // G1 write-barrier post: executed after a pointer store.

 JRT_LEAF(void, SharedRuntime::g1_wb_post(void* card_addr, JavaThread* thread))

   thread->dirty_card_queue().enqueue(card_addr);

 JRT_END

 #endif // INCLUDE_ALL_GCS

 JRT_LEAF(jlong, SharedRuntime::lmul(jlong y, jlong x))

   return x * y;

 JRT_END

 JRT_LEAF(jlong, SharedRuntime::ldiv(jlong y, jlong x))

   if (x == min_jlong && y == CONST64(-1)) {

     return x;

   } else {

     return x / y;

   }

 JRT_END

 JRT_LEAF(jlong, SharedRuntime::lrem(jlong y, jlong x))

   if (x == min_jlong && y == CONST64(-1)) {

     return 0;

   } else {

     return x % y;

   }

 JRT_END

 const juint  float_sign_mask  = 0x7FFFFFFF;

 const juint  float_infinity   = 0x7F800000;

 const julong double_sign_mask = CONST64(0x7FFFFFFFFFFFFFFF);

 const julong double_infinity  = CONST64(0x7FF0000000000000);

 JRT_LEAF(jfloat, SharedRuntime::frem(jfloat  x, jfloat  y))

 #ifdef _WIN64

   // 64-bit Windows on amd64 returns the wrong values for

   // infinity operands.

   union { jfloat f; juint i; } xbits, ybits;

   xbits.f = x;

   ybits.f = y;

   // x Mod Infinity == x unless x is infinity

   if ( ((xbits.i & float_sign_mask) != float_infinity) &&

        ((ybits.i & float_sign_mask) == float_infinity) ) {

     return x;

   }

 #endif

   return ((jfloat)fmod((double)x,(double)y));

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::drem(jdouble x, jdouble y))

 #ifdef _WIN64

   union { jdouble d; julong l; } xbits, ybits;

   xbits.d = x;

   ybits.d = y;

   // x Mod Infinity == x unless x is infinity

   if ( ((xbits.l & double_sign_mask) != double_infinity) &&

        ((ybits.l & double_sign_mask) == double_infinity) ) {

     return x;

   }

 #endif

   return ((jdouble)fmod((double)x,(double)y));

 JRT_END

 #ifdef __SOFTFP__

 JRT_LEAF(jfloat, SharedRuntime::fadd(jfloat x, jfloat y))

   return x + y;

 JRT_END

 JRT_LEAF(jfloat, SharedRuntime::fsub(jfloat x, jfloat y))

   return x - y;

 JRT_END

 JRT_LEAF(jfloat, SharedRuntime::fmul(jfloat x, jfloat y))

   return x * y;

 JRT_END

 JRT_LEAF(jfloat, SharedRuntime::fdiv(jfloat x, jfloat y))

   return x / y;

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::dadd(jdouble x, jdouble y))

   return x + y;

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::dsub(jdouble x, jdouble y))

   return x - y;

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::dmul(jdouble x, jdouble y))

   return x * y;

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::ddiv(jdouble x, jdouble y))

   return x / y;

 JRT_END

 JRT_LEAF(jfloat, SharedRuntime::i2f(jint x))

   return (jfloat)x;

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::i2d(jint x))

   return (jdouble)x;

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::f2d(jfloat x))

   return (jdouble)x;

 JRT_END

 JRT_LEAF(int,  SharedRuntime::fcmpl(float x, float y))

   return x>y ? 1 : (x==y ? 0 : -1);  /* x<y or is_nan*/

 JRT_END

 JRT_LEAF(int,  SharedRuntime::fcmpg(float x, float y))

   return x<y ? -1 : (x==y ? 0 : 1);  /* x>y or is_nan */

 JRT_END

 JRT_LEAF(int,  SharedRuntime::dcmpl(double x, double y))

   return x>y ? 1 : (x==y ? 0 : -1); /* x<y or is_nan */

 JRT_END

 JRT_LEAF(int,  SharedRuntime::dcmpg(double x, double y))

   return x<y ? -1 : (x==y ? 0 : 1);  /* x>y or is_nan */

 JRT_END

 // Functions to return the opposite of the aeabi functions for nan.

 JRT_LEAF(int, SharedRuntime::unordered_fcmplt(float x, float y))

   return (x < y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 JRT_LEAF(int, SharedRuntime::unordered_dcmplt(double x, double y))

   return (x < y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 JRT_LEAF(int, SharedRuntime::unordered_fcmple(float x, float y))

   return (x <= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 JRT_LEAF(int, SharedRuntime::unordered_dcmple(double x, double y))

   return (x <= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 JRT_LEAF(int, SharedRuntime::unordered_fcmpge(float x, float y))

   return (x >= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 JRT_LEAF(int, SharedRuntime::unordered_dcmpge(double x, double y))

   return (x >= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 JRT_LEAF(int, SharedRuntime::unordered_fcmpgt(float x, float y))

   return (x > y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 JRT_LEAF(int, SharedRuntime::unordered_dcmpgt(double x, double y))

   return (x > y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);

 JRT_END

 // Intrinsics make gcc generate code for these.

 float  SharedRuntime::fneg(float f)   {

   return -f;

 }

 double SharedRuntime::dneg(double f)  {

   return -f;

 }

 #endif // __SOFTFP__

 #if defined(__SOFTFP__) || defined(E500V2)

 // Intrinsics make gcc generate code for these.

 double SharedRuntime::dabs(double f)  {

   return (f <= (double)0.0) ? (double)0.0 - f : f;

 }

 #endif

 #if defined(__SOFTFP__) || defined(PPC32)

 double SharedRuntime::dsqrt(double f) {

   return sqrt(f);

 }

 #endif

 JRT_LEAF(jint, SharedRuntime::f2i(jfloat  x))

   if (g_isnan(x))

     return 0;

   if (x >= (jfloat) max_jint)

     return max_jint;

   if (x <= (jfloat) min_jint)

     return min_jint;

   return (jint) x;

 JRT_END

 JRT_LEAF(jlong, SharedRuntime::f2l(jfloat  x))

   if (g_isnan(x))

     return 0;

   if (x >= (jfloat) max_jlong)

     return max_jlong;

   if (x <= (jfloat) min_jlong)

     return min_jlong;

   return (jlong) x;

 JRT_END

 JRT_LEAF(jint, SharedRuntime::d2i(jdouble x))

   if (g_isnan(x))

     return 0;

   if (x >= (jdouble) max_jint)

     return max_jint;

   if (x <= (jdouble) min_jint)

     return min_jint;

   return (jint) x;

 JRT_END

 JRT_LEAF(jlong, SharedRuntime::d2l(jdouble x))

   if (g_isnan(x))

     return 0;

   if (x >= (jdouble) max_jlong)

     return max_jlong;

   if (x <= (jdouble) min_jlong)

     return min_jlong;

   return (jlong) x;

 JRT_END

 JRT_LEAF(jfloat, SharedRuntime::d2f(jdouble x))

   return (jfloat)x;

 JRT_END

 JRT_LEAF(jfloat, SharedRuntime::l2f(jlong x))

   return (jfloat)x;

 JRT_END

 JRT_LEAF(jdouble, SharedRuntime::l2d(jlong x))

   return (jdouble)x;

 JRT_END

 // Exception handling accross interpreter/compiler boundaries

 //

 // exception_handler_for_return_address(...) returns the continuation address.

 // The continuation address is the entry point of the exception handler of the

 // previous frame depending on the return address.

 address SharedRuntime::raw_exception_handler_for_return_address(JavaThread* thread, address return_address) {

   assert(frame::verify_return_pc(return_address), err_msg("must be a return address: " INTPTR_FORMAT, return_address));

   assert(thread->frames_to_pop_failed_realloc() == 0 || Interpreter::contains(return_address), "missed frames to pop?");

   // Reset method handle flag.

   thread->set_is_method_handle_return(false);

   // The fastest case first

   CodeBlob* blob = CodeCache::find_blob(return_address);

   nmethod* nm = (blob != NULL) ? blob->as_nmethod_or_null() : NULL;

   if (nm != NULL) {

     // Set flag if return address is a method handle call site.

     thread->set_is_method_handle_return(nm->is_method_handle_return(return_address));

     // native nmethods don't have exception handlers

     assert(!nm->is_native_method(), "no exception handler");

     assert(nm->header_begin() != nm->exception_begin(), "no exception handler");

     if (nm->is_deopt_pc(return_address)) {

       // If we come here because of a stack overflow, the stack may be

       // unguarded. Reguard the stack otherwise if we return to the

       // deopt blob and the stack bang causes a stack overflow we

       // crash.

       bool guard_pages_enabled = thread->stack_yellow_zone_enabled();

       if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();

       assert(guard_pages_enabled, "stack banging in deopt blob may cause crash");

       return SharedRuntime::deopt_blob()->unpack_with_exception();

     } else {

       return nm->exception_begin();

     }

   }

   // Entry code

   if (StubRoutines::returns_to_call_stub(return_address)) {

     return StubRoutines::catch_exception_entry();

   }

   // Interpreted code

   if (Interpreter::contains(return_address)) {

     return Interpreter::rethrow_exception_entry();

   }

   guarantee(blob == NULL || !blob->is_runtime_stub(), "caller should have skipped stub");

   guarantee(!VtableStubs::contains(return_address), "NULL exceptions in vtables should have been handled already!");

 #ifndef PRODUCT

   { ResourceMark rm;

     tty->print_cr("No exception handler found for exception at " INTPTR_FORMAT " - potential problems:", return_address);

     tty->print_cr("a) exception happened in (new?) code stubs/buffers that is not handled here");

     tty->print_cr("b) other problem");

   }

 #endif // PRODUCT

   ShouldNotReachHere();

   return NULL;

 }

 JRT_LEAF(address, SharedRuntime::exception_handler_for_return_address(JavaThread* thread, address return_address))

   return raw_exception_handler_for_return_address(thread, return_address);

 JRT_END

 address SharedRuntime::get_poll_stub(address pc) {

   address stub;

   // Look up the code blob

   CodeBlob *cb = CodeCache::find_blob(pc);

   // Should be an nmethod

   guarantee(cb != NULL && cb->is_nmethod(), "safepoint polling: pc must refer to an nmethod");

   // Look up the relocation information

   assert( ((nmethod*)cb)->is_at_poll_or_poll_return(pc),

     "safepoint polling: type must be poll" );

   assert( ((NativeInstruction*)pc)->is_safepoint_poll(),

     "Only polling locations are used for safepoint");

   bool at_poll_return = ((nmethod*)cb)->is_at_poll_return(pc);

   bool has_wide_vectors = ((nmethod*)cb)->has_wide_vectors();

   if (at_poll_return) {

     assert(SharedRuntime::polling_page_return_handler_blob() != NULL,

            "polling page return stub not created yet");

     stub = SharedRuntime::polling_page_return_handler_blob()->entry_point();

   } else if (has_wide_vectors) {

     assert(SharedRuntime::polling_page_vectors_safepoint_handler_blob() != NULL,

            "polling page vectors safepoint stub not created yet");

     stub = SharedRuntime::polling_page_vectors_safepoint_handler_blob()->entry_point();

   } else {

     assert(SharedRuntime::polling_page_safepoint_handler_blob() != NULL,

            "polling page safepoint stub not created yet");

     stub = SharedRuntime::polling_page_safepoint_handler_blob()->entry_point();

   }

 #ifndef PRODUCT

   if( TraceSafepoint ) {

     char buf[256];

     jio_snprintf(buf, sizeof(buf),

                  "... found polling page %s exception at pc = "

                  INTPTR_FORMAT ", stub =" INTPTR_FORMAT,

                  at_poll_return ? "return" : "loop",

                  (intptr_t)pc, (intptr_t)stub);

     tty->print_raw_cr(buf);

   }

 #endif // PRODUCT

   return stub;

 }

 oop SharedRuntime::retrieve_receiver( Symbol* sig, frame caller ) {

   assert(caller.is_interpreted_frame(), "");

   int args_size = ArgumentSizeComputer(sig).size() + 1;

   assert(args_size <= caller.interpreter_frame_expression_stack_size(), "receiver must be on interpreter stack");

   oop result = cast_to_oop(*caller.interpreter_frame_tos_at(args_size - 1));

   assert(Universe::heap()->is_in(result) && result->is_oop(), "receiver must be an oop");

   return result;

 }

 void SharedRuntime::throw_and_post_jvmti_exception(JavaThread *thread, Handle h_exception) {

   if (JvmtiExport::can_post_on_exceptions()) {

     vframeStream vfst(thread, true);

     methodHandle method = methodHandle(thread, vfst.method());

     address bcp = method()->bcp_from(vfst.bci());

     JvmtiExport::post_exception_throw(thread, method(), bcp, h_exception());

   }

   Exceptions::_throw(thread, __FILE__, __LINE__, h_exception);

 }

 void SharedRuntime::throw_and_post_jvmti_exception(JavaThread *thread, Symbol* name, const char *message) {

   Handle h_exception = Exceptions::new_exception(thread, name, message);

   throw_and_post_jvmti_exception(thread, h_exception);

 }

 // The interpreter code to call this tracing function is only

 // called/generated when TraceRedefineClasses has the right bits

 // set. Since obsolete methods are never compiled, we don't have

 // to modify the compilers to generate calls to this function.

 //

 JRT_LEAF(int, SharedRuntime::rc_trace_method_entry(

     JavaThread* thread, Method* method))

   assert(RC_TRACE_IN_RANGE(0x00001000, 0x00002000), "wrong call");

   if (method->is_obsolete()) {

     // We are calling an obsolete method, but this is not necessarily

     // an error. Our method could have been redefined just after we

     // fetched the Method* from the constant pool.

     // RC_TRACE macro has an embedded ResourceMark

     RC_TRACE_WITH_THREAD(0x00001000, thread,

                          ("calling obsolete method '%s'",

                           method->name_and_sig_as_C_string()));

     if (RC_TRACE_ENABLED(0x00002000)) {

       // this option is provided to debug calls to obsolete methods

       guarantee(false, "faulting at call to an obsolete method.");

     }

   }

   return 0;

 JRT_END

 // ret_pc points into caller; we are returning caller's exception handler

 // for given exception

 address SharedRuntime::compute_compiled_exc_handler(nmethod* nm, address ret_pc, Handle& exception,

                                                     bool force_unwind, bool top_frame_only) {

   assert(nm != NULL, "must exist");

   ResourceMark rm;

   ScopeDesc* sd = nm->scope_desc_at(ret_pc);

   // determine handler bci, if any

   EXCEPTION_MARK;

   int handler_bci = -1;

   int scope_depth = 0;

   if (!force_unwind) {

     int bci = sd->bci();

     bool recursive_exception = false;

     do {

       bool skip_scope_increment = false;

       // exception handler lookup

       KlassHandle ek (THREAD, exception->klass());

       methodHandle mh(THREAD, sd->method());

       handler_bci = Method::fast_exception_handler_bci_for(mh, ek, bci, THREAD);

       if (HAS_PENDING_EXCEPTION) {

         recursive_exception = true;

         // We threw an exception while trying to find the exception handler.

         // Transfer the new exception to the exception handle which will

         // be set into thread local storage, and do another lookup for an

         // exception handler for this exception, this time starting at the

         // BCI of the exception handler which caused the exception to be

         // thrown (bugs 4307310 and 4546590). Set "exception" reference

         // argument to ensure that the correct exception is thrown (4870175).

         exception = Handle(THREAD, PENDING_EXCEPTION);

         CLEAR_PENDING_EXCEPTION;

         if (handler_bci >= 0) {

           bci = handler_bci;

           handler_bci = -1;

           skip_scope_increment = true;

         }

       }

       else {

         recursive_exception = false;

       }

       if (!top_frame_only && handler_bci < 0 && !skip_scope_increment) {

         sd = sd->sender();

         if (sd != NULL) {

           bci = sd->bci();

         }

         ++scope_depth;

       }

     } while (recursive_exception || (!top_frame_only && handler_bci < 0 && sd != NULL));

   }

   // found handling method => lookup exception handler

   int catch_pco = ret_pc - nm->code_begin();

   ExceptionHandlerTable table(nm);

   HandlerTableEntry *t = table.entry_for(catch_pco, handler_bci, scope_depth);

   if (t == NULL && (nm->is_compiled_by_c1() || handler_bci != -1)) {

     // Allow abbreviated catch tables.  The idea is to allow a method

     // to materialize its exceptions without committing to the exact

     // routing of exceptions.  In particular this is needed for adding

     // a synthethic handler to unlock monitors when inlining

     // synchonized methods since the unlock path isn't represented in

     // the bytecodes.

     t = table.entry_for(catch_pco, -1, 0);

   }

 #ifdef COMPILER1

   if (t == NULL && nm->is_compiled_by_c1()) {

     assert(nm->unwind_handler_begin() != NULL, "");

     return nm->unwind_handler_begin();

   }

 #endif

   if (t == NULL) {

     tty->print_cr("MISSING EXCEPTION HANDLER for pc " INTPTR_FORMAT " and handler bci %d", ret_pc, handler_bci);

     tty->print_cr("   Exception:");

     exception->print();

     tty->cr();

     tty->print_cr(" Compiled exception table :");

     table.print();

     nm->print_code();

     guarantee(false, "missing exception handler");

     return NULL;

   }

   return nm->code_begin() + t->pco();

 }

 JRT_ENTRY(void, SharedRuntime::throw_AbstractMethodError(JavaThread* thread))

   // These errors occur only at call sites

   throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_AbstractMethodError());

 JRT_END

 JRT_ENTRY(void, SharedRuntime::throw_IncompatibleClassChangeError(JavaThread* thread))

   // These errors occur only at call sites

   throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IncompatibleClassChangeError(), "vtable stub");

 JRT_END

 JRT_ENTRY(void, SharedRuntime::throw_ArithmeticException(JavaThread* thread))

   throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArithmeticException(), "/ by zero");

 JRT_END

 JRT_ENTRY(void, SharedRuntime::throw_NullPointerException(JavaThread* thread))

   throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());

 JRT_END

 JRT_ENTRY(void, SharedRuntime::throw_NullPointerException_at_call(JavaThread* thread))

   // This entry point is effectively only used for NullPointerExceptions which occur at inline

   // cache sites (when the callee activation is not yet set up) so we are at a call site

   throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());

 JRT_END

 JRT_ENTRY(void, SharedRuntime::throw_StackOverflowError(JavaThread* thread))

   // We avoid using the normal exception construction in this case because

   // it performs an upcall to Java, and we're already out of stack space.

   Klass* k = SystemDictionary::StackOverflowError_klass();

   oop exception_oop = InstanceKlass::cast(k)->allocate_instance(CHECK);

   Handle exception (thread, exception_oop);

   if (StackTraceInThrowable) {

     java_lang_Throwable::fill_in_stack_trace(exception);

   }

   throw_and_post_jvmti_exception(thread, exception);

 JRT_END

 address SharedRuntime::continuation_for_implicit_exception(JavaThread* thread,

                                                            address pc,

                                                            SharedRuntime::ImplicitExceptionKind exception_kind)

 {

   address target_pc = NULL;

   if (Interpreter::contains(pc)) {

 #ifdef CC_INTERP

     // C++ interpreter doesn't throw implicit exceptions

     ShouldNotReachHere();

 #else

     switch (exception_kind) {

       case IMPLICIT_NULL:           return Interpreter::throw_NullPointerException_entry();

       case IMPLICIT_DIVIDE_BY_ZERO: return Interpreter::throw_ArithmeticException_entry();

       case STACK_OVERFLOW:          return Interpreter::throw_StackOverflowError_entry();

       default:                      ShouldNotReachHere();

     }

 #endif // !CC_INTERP

   } else {

     switch (exception_kind) {

       case STACK_OVERFLOW: {

         // Stack overflow only occurs upon frame setup; the callee is

         // going to be unwound. Dispatch to a shared runtime stub

         // which will cause the StackOverflowError to be fabricated

         // and processed.

         // Stack overflow should never occur during deoptimization:

         // the compiled method bangs the stack by as much as the

         // interpreter would need in case of a deoptimization. The

         // deoptimization blob and uncommon trap blob bang the stack

         // in a debug VM to verify the correctness of the compiled

         // method stack banging.

         assert(thread->deopt_mark() == NULL, "no stack overflow from deopt blob/uncommon trap");

         Events::log_exception(thread, "StackOverflowError at " INTPTR_FORMAT, pc);

         return StubRoutines::throw_StackOverflowError_entry();

       }

       case IMPLICIT_NULL: {

         if (VtableStubs::contains(pc)) {

           // We haven't yet entered the callee frame. Fabricate an

           // exception and begin dispatching it in the caller. Since

           // the caller was at a call site, it's safe to destroy all

           // caller-saved registers, as these entry points do.

           VtableStub* vt_stub = VtableStubs::stub_containing(pc);

           // If vt_stub is NULL, then return NULL to signal handler to report the SEGV error.

           if (vt_stub == NULL) return NULL;

           if (vt_stub->is_abstract_method_error(pc)) {

             assert(!vt_stub->is_vtable_stub(), "should never see AbstractMethodErrors from vtable-type VtableStubs");

             Events::log_exception(thread, "AbstractMethodError at " INTPTR_FORMAT, pc);

             return StubRoutines::throw_AbstractMethodError_entry();

           } else {

             Events::log_exception(thread, "NullPointerException at vtable entry " INTPTR_FORMAT, pc);

             return StubRoutines::throw_NullPointerException_at_call_entry();

           }

         } else {

           CodeBlob* cb = CodeCache::find_blob(pc);

           // If code blob is NULL, then return NULL to signal handler to report the SEGV error.

           if (cb == NULL) return NULL;

           // Exception happened in CodeCache. Must be either:

           // 1. Inline-cache check in C2I handler blob,

           // 2. Inline-cache check in nmethod, or

           // 3. Implict null exception in nmethod

           if (!cb->is_nmethod()) {

             bool is_in_blob = cb->is_adapter_blob() || cb->is_method_handles_adapter_blob();

             if (!is_in_blob) {

               cb->print();

               fatal(err_msg("exception happened outside interpreter, nmethods and vtable stubs at pc " INTPTR_FORMAT, pc));

             }

             Events::log_exception(thread, "NullPointerException in code blob at " INTPTR_FORMAT, pc);

             // There is no handler here, so we will simply unwind.

             return StubRoutines::throw_NullPointerException_at_call_entry();

           }

           // Otherwise, it's an nmethod.  Consult its exception handlers.

           nmethod* nm = (nmethod*)cb;

           if (nm->inlinecache_check_contains(pc)) {

             // exception happened inside inline-cache check code

             // => the nmethod is not yet active (i.e., the frame

             // is not set up yet) => use return address pushed by

             // caller => don't push another return address

             Events::log_exception(thread, "NullPointerException in IC check " INTPTR_FORMAT, pc);

             return StubRoutines::throw_NullPointerException_at_call_entry();

           }

           if (nm->method()->is_method_handle_intrinsic()) {

             // exception happened inside MH dispatch code, similar to a vtable stub

             Events::log_exception(thread, "NullPointerException in MH adapter " INTPTR_FORMAT, pc);

             return StubRoutines::throw_NullPointerException_at_call_entry();

           }

 #ifndef PRODUCT

           _implicit_null_throws++;

 #endif

           target_pc = nm->continuation_for_implicit_exception(pc);

           // If there's an unexpected fault, target_pc might be NULL,

           // in which case we want to fall through into the normal

           // error handling code.

         }

         break; // fall through

       }

       case IMPLICIT_DIVIDE_BY_ZERO: {

         nmethod* nm = CodeCache::find_nmethod(pc);

         guarantee(nm != NULL, "must have containing nmethod for implicit division-by-zero exceptions");

 #ifndef PRODUCT

         _implicit_div0_throws++;

 #endif

         target_pc = nm->continuation_for_implicit_exception(pc);

         // If there's an unexpected fault, target_pc might be NULL,

         // in which case we want to fall through into the normal

         // error handling code.

         break; // fall through

       }

       default: ShouldNotReachHere();

     }

     assert(exception_kind == IMPLICIT_NULL || exception_kind == IMPLICIT_DIVIDE_BY_ZERO, "wrong implicit exception kind");

     // for AbortVMOnException flag

     NOT_PRODUCT(Exceptions::debug_check_abort("java.lang.NullPointerException"));

     if (exception_kind == IMPLICIT_NULL) {

       Events::log_exception(thread, "Implicit null exception at " INTPTR_FORMAT " to " INTPTR_FORMAT, pc, target_pc);

     } else {

       Events::log_exception(thread, "Implicit division by zero exception at " INTPTR_FORMAT " to " INTPTR_FORMAT, pc, target_pc);

     }

     return target_pc;

   }

   ShouldNotReachHere();

   return NULL;

 }

 /**

  * Throws an java/lang/UnsatisfiedLinkError.  The address of this method is

  * installed in the native function entry of all native Java methods before

  * they get linked to their actual native methods.

  *

  * \note

  * This method actually never gets called!  The reason is because

  * the interpreter's native entries call NativeLookup::lookup() which

  * throws the exception when the lookup fails.  The exception is then

  * caught and forwarded on the return from NativeLookup::lookup() call

  * before the call to the native function.  This might change in the future.

  */

 JNI_ENTRY(void*, throw_unsatisfied_link_error(JNIEnv* env, ...))

 {

   // We return a bad value here to make sure that the exception is

   // forwarded before we look at the return value.

   THROW_(vmSymbols::java_lang_UnsatisfiedLinkError(), (void*)badJNIHandle);

 }

 JNI_END

 address SharedRuntime::native_method_throw_unsatisfied_link_error_entry() {

   return CAST_FROM_FN_PTR(address, &throw_unsatisfied_link_error);

 }

 #ifndef PRODUCT

 JRT_ENTRY(intptr_t, SharedRuntime::trace_bytecode(JavaThread* thread, intptr_t preserve_this_value, intptr_t tos, intptr_t tos2))

   const frame f = thread->last_frame();

   assert(f.is_interpreted_frame(), "must be an interpreted frame");

 #ifndef PRODUCT

   methodHandle mh(THREAD, f.interpreter_frame_method());

   BytecodeTracer::trace(mh, f.interpreter_frame_bcp(), tos, tos2);

 #endif // !PRODUCT

   return preserve_this_value;

 JRT_END

 #endif // !PRODUCT

 JRT_ENTRY(void, SharedRuntime::yield_all(JavaThread* thread, int attempts))

   os::yield_all(attempts);

 JRT_END

 JRT_ENTRY_NO_ASYNC(void, SharedRuntime::register_finalizer(JavaThread* thread, oopDesc* obj))

   assert(obj->is_oop(), "must be a valid oop");

   assert(obj->klass()->has_finalizer(), "shouldn't be here otherwise");

   InstanceKlass::register_finalizer(instanceOop(obj), CHECK);

 JRT_END

 jlong SharedRuntime::get_java_tid(Thread* thread) {

   if (thread != NULL) {

     if (thread->is_Java_thread()) {

       oop obj = ((JavaThread*)thread)->threadObj();

       return (obj == NULL) ? 0 : java_lang_Thread::thread_id(obj);

     }

   }

   return 0;

 }

 /**

  * This function ought to be a void function, but cannot be because

  * it gets turned into a tail-call on sparc, which runs into dtrace bug

  * 6254741.  Once that is fixed we can remove the dummy return value.

  */

 int SharedRuntime::dtrace_object_alloc(oopDesc* o, int size) {

   return dtrace_object_alloc_base(Thread::current(), o, size);

 }

 int SharedRuntime::dtrace_object_alloc_base(Thread* thread, oopDesc* o, int size) {

   assert(DTraceAllocProbes, "wrong call");

   Klass* klass = o->klass();

   Symbol* name = klass->name();

 #ifndef USDT2

   HS_DTRACE_PROBE4(hotspot, object__alloc, get_java_tid(thread),

                    name->bytes(), name->utf8_length(), size * HeapWordSize);

 #else /* USDT2 */

   HOTSPOT_OBJECT_ALLOC(

                    get_java_tid(thread),

                    (char *) name->bytes(), name->utf8_length(), size * HeapWordSize);

 #endif /* USDT2 */

   return 0;

 }

 JRT_LEAF(int, SharedRuntime::dtrace_method_entry(

     JavaThread* thread, Method* method))

   assert(DTraceMethodProbes, "wrong call");

   Symbol* kname = method->klass_name();

   Symbol* name = method->name();

   Symbol* sig = method->signature();

 #ifndef USDT2

   HS_DTRACE_PROBE7(hotspot, method__entry, get_java_tid(thread),

       kname->bytes(), kname->utf8_length(),

       name->bytes(), name->utf8_length(),

       sig->bytes(), sig->utf8_length());

 #else /* USDT2 */

   HOTSPOT_METHOD_ENTRY(

       get_java_tid(thread),

       (char *) kname->bytes(), kname->utf8_length(),

       (char *) name->bytes(), name->utf8_length(),

       (char *) sig->bytes(), sig->utf8_length());

 #endif /* USDT2 */

   return 0;

 JRT_END

 JRT_LEAF(int, SharedRuntime::dtrace_method_exit(

     JavaThread* thread, Method* method))

   assert(DTraceMethodProbes, "wrong call");

   Symbol* kname = method->klass_name();

   Symbol* name = method->name();

   Symbol* sig = method->signature();

 #ifndef USDT2

   HS_DTRACE_PROBE7(hotspot, method__return, get_java_tid(thread),

       kname->bytes(), kname->utf8_length(),

       name->bytes(), name->utf8_length(),

       sig->bytes(), sig->utf8_length());

 #else /* USDT2 */

   HOTSPOT_METHOD_RETURN(

       get_java_tid(thread),

       (char *) kname->bytes(), kname->utf8_length(),

       (char *) name->bytes(), name->utf8_length(),

       (char *) sig->bytes(), sig->utf8_length());

 #endif /* USDT2 */

   return 0;

 JRT_END

 // Finds receiver, CallInfo (i.e. receiver method), and calling bytecode)

 // for a call current in progress, i.e., arguments has been pushed on stack

 // put callee has not been invoked yet.  Used by: resolve virtual/static,

 // vtable updates, etc.  Caller frame must be compiled.

 Handle SharedRuntime::find_callee_info(JavaThread* thread, Bytecodes::Code& bc, CallInfo& callinfo, TRAPS) {

   ResourceMark rm(THREAD);

   // last java frame on stack (which includes native call frames)

   vframeStream vfst(thread, true);  // Do not skip and javaCalls

   return find_callee_info_helper(thread, vfst, bc, callinfo, CHECK_(Handle()));

 }

 // Finds receiver, CallInfo (i.e. receiver method), and calling bytecode

 // for a call current in progress, i.e., arguments has been pushed on stack

 // but callee has not been invoked yet.  Caller frame must be compiled.

 Handle SharedRuntime::find_callee_info_helper(JavaThread* thread,

                                               vframeStream& vfst,

                                               Bytecodes::Code& bc,

                                               CallInfo& callinfo, TRAPS) {

   Handle receiver;

   Handle nullHandle;  //create a handy null handle for exception returns

   assert(!vfst.at_end(), "Java frame must exist");

   // Find caller and bci from vframe

   methodHandle caller(THREAD, vfst.method());

   int          bci   = vfst.bci();

   // Find bytecode

   Bytecode_invoke bytecode(caller, bci);

   bc = bytecode.invoke_code();

   int bytecode_index = bytecode.index();

   // Find receiver for non-static call

   if (bc != Bytecodes::_invokestatic &&

       bc != Bytecodes::_invokedynamic &&

       bc != Bytecodes::_invokehandle) {

     // This register map must be update since we need to find the receiver for

     // compiled frames. The receiver might be in a register.

     RegisterMap reg_map2(thread);

     frame stubFrame   = thread->last_frame();

     // Caller-frame is a compiled frame

     frame callerFrame = stubFrame.sender(&reg_map2);

     methodHandle callee = bytecode.static_target(CHECK_(nullHandle));

     if (callee.is_null()) {

       THROW_(vmSymbols::java_lang_NoSuchMethodException(), nullHandle);

     }

     // Retrieve from a compiled argument list

     receiver = Handle(THREAD, callerFrame.retrieve_receiver(&reg_map2));

     if (receiver.is_null()) {

       THROW_(vmSymbols::java_lang_NullPointerException(), nullHandle);

     }

   }

   // Resolve method. This is parameterized by bytecode.

   constantPoolHandle constants(THREAD, caller->constants());

   assert(receiver.is_null() || receiver->is_oop(), "wrong receiver");

   LinkResolver::resolve_invoke(callinfo, receiver, constants, bytecode_index, bc, CHECK_(nullHandle));

 #ifdef ASSERT

   // Check that the receiver klass is of the right subtype and that it is initialized for virtual calls

   if (bc != Bytecodes::_invokestatic && bc != Bytecodes::_invokedynamic && bc != Bytecodes::_invokehandle) {

     assert(receiver.not_null(), "should have thrown exception");

     KlassHandle receiver_klass(THREAD, receiver->klass());

     Klass* rk = constants->klass_ref_at(bytecode_index, CHECK_(nullHandle));

                             // klass is already loaded

     KlassHandle static_receiver_klass(THREAD, rk);

     // Method handle invokes might have been optimized to a direct call

     // so don't check for the receiver class.

     // FIXME this weakens the assert too much

     methodHandle callee = callinfo.selected_method();

     assert(receiver_klass->is_subtype_of(static_receiver_klass()) ||

            callee->is_method_handle_intrinsic() ||

            callee->is_compiled_lambda_form(),

            "actual receiver must be subclass of static receiver klass");

     if (receiver_klass->oop_is_instance()) {

       if (InstanceKlass::cast(receiver_klass())->is_not_initialized()) {

         tty->print_cr("ERROR: Klass not yet initialized!!");

         receiver_klass()->print();

       }

       assert(!InstanceKlass::cast(receiver_klass())->is_not_initialized(), "receiver_klass must be initialized");

     }

   }

 #endif

   return receiver;

 }

 methodHandle SharedRuntime::find_callee_method(JavaThread* thread, TRAPS) {

   ResourceMark rm(THREAD);

   // We need first to check if any Java activations (compiled, interpreted)

   // exist on the stack since last JavaCall.  If not, we need

   // to get the target method from the JavaCall wrapper.

   vframeStream vfst(thread, true);  // Do not skip any javaCalls

   methodHandle callee_method;

   if (vfst.at_end()) {

     // No Java frames were found on stack since we did the JavaCall.

     // Hence the stack can only contain an entry_frame.  We need to

     // find the target method from the stub frame.

     RegisterMap reg_map(thread, false);

     frame fr = thread->last_frame();

     assert(fr.is_runtime_frame(), "must be a runtimeStub");

     fr = fr.sender(&reg_map);

     assert(fr.is_entry_frame(), "must be");

     // fr is now pointing to the entry frame.

     callee_method = methodHandle(THREAD, fr.entry_frame_call_wrapper()->callee_method());

     assert(fr.entry_frame_call_wrapper()->receiver() == NULL || !callee_method->is_static(), "non-null receiver for static call??");

   } else {

     Bytecodes::Code bc;

     CallInfo callinfo;

     find_callee_info_helper(thread, vfst, bc, callinfo, CHECK_(methodHandle()));

     callee_method = callinfo.selected_method();

   }

   assert(callee_method()->is_method(), "must be");

   return callee_method;

 }

 // Resolves a call.

 methodHandle SharedRuntime::resolve_helper(JavaThread *thread,

                                            bool is_virtual,

                                            bool is_optimized, TRAPS) {

   methodHandle callee_method;

   callee_method = resolve_sub_helper(thread, is_virtual, is_optimized, THREAD);

   if (JvmtiExport::can_hotswap_or_post_breakpoint()) {

     int retry_count = 0;

     while (!HAS_PENDING_EXCEPTION && callee_method->is_old() &&

            callee_method->method_holder() != SystemDictionary::Object_klass()) {

       // If has a pending exception then there is no need to re-try to

       // resolve this method.

       // If the method has been redefined, we need to try again.

       // Hack: we have no way to update the vtables of arrays, so don't

       // require that java.lang.Object has been updated.

       // It is very unlikely that method is redefined more than 100 times

       // in the middle of resolve. If it is looping here more than 100 times

       // means then there could be a bug here.

       guarantee((retry_count++ < 100),

                 "Could not resolve to latest version of redefined method");

       // method is redefined in the middle of resolve so re-try.

       callee_method = resolve_sub_helper(thread, is_virtual, is_optimized, THREAD);

     }

   }

   return callee_method;

 }

 // Resolves a call.  The compilers generate code for calls that go here

 // and are patched with the real destination of the call.

 methodHandle SharedRuntime::resolve_sub_helper(JavaThread *thread,

                                            bool is_virtual,

                                            bool is_optimized, TRAPS) {

   ResourceMark rm(thread);

   RegisterMap cbl_map(thread, false);

   frame caller_frame = thread->last_frame().sender(&cbl_map);

   CodeBlob* caller_cb = caller_frame.cb();

   guarantee(caller_cb != NULL && caller_cb->is_nmethod(), "must be called from nmethod");

   nmethod* caller_nm = caller_cb->as_nmethod_or_null();

   // make sure caller is not getting deoptimized

   // and removed before we are done with it.

   // CLEANUP - with lazy deopt shouldn't need this lock

   nmethodLocker caller_lock(caller_nm);

   // determine call info & receiver

   // note: a) receiver is NULL for static calls

   //       b) an exception is thrown if receiver is NULL for non-static calls

   CallInfo call_info;

   Bytecodes::Code invoke_code = Bytecodes::_illegal;

   Handle receiver = find_callee_info(thread, invoke_code,

                                      call_info, CHECK_(methodHandle()));

   methodHandle callee_method = call_info.selected_method();

   assert((!is_virtual && invoke_code == Bytecodes::_invokestatic ) ||

          (!is_virtual && invoke_code == Bytecodes::_invokehandle ) ||

          (!is_virtual && invoke_code == Bytecodes::_invokedynamic) ||

          ( is_virtual && invoke_code != Bytecodes::_invokestatic ), "inconsistent bytecode");

   assert(caller_nm->is_alive(), "It should be alive");

 #ifndef PRODUCT

   // tracing/debugging/statistics

   int *addr = (is_optimized) ? (&_resolve_opt_virtual_ctr) :

                 (is_virtual) ? (&_resolve_virtual_ctr) :

                                (&_resolve_static_ctr);

   Atomic::inc(addr);

   if (TraceCallFixup) {

     ResourceMark rm(thread);

     tty->print("resolving %s%s (%s) call to",

       (is_optimized) ? "optimized " : "", (is_virtual) ? "virtual" : "static",

       Bytecodes::name(invoke_code));

     callee_method->print_short_name(tty);

     tty->print_cr(" at pc: " INTPTR_FORMAT " to code: " INTPTR_FORMAT, caller_frame.pc(), callee_method->code());

   }

 #endif

   // JSR 292 key invariant:

   // If the resolved method is a MethodHandle invoke target, the call

   // site must be a MethodHandle call site, because the lambda form might tail-call

   // leaving the stack in a state unknown to either caller or callee

   // TODO detune for now but we might need it again

 //  assert(!callee_method->is_compiled_lambda_form() ||

 //         caller_nm->is_method_handle_return(caller_frame.pc()), "must be MH call site");

   // Compute entry points. This might require generation of C2I converter

   // frames, so we cannot be holding any locks here. Furthermore, the

   // computation of the entry points is independent of patching the call.  We

   // always return the entry-point, but we only patch the stub if the call has

   // not been deoptimized.  Return values: For a virtual call this is an

   // (cached_oop, destination address) pair. For a static call/optimized

   // virtual this is just a destination address.

   StaticCallInfo static_call_info;

   CompiledICInfo virtual_call_info;

   // Make sure the callee nmethod does not get deoptimized and removed before

   // we are done patching the code.

   nmethod* callee_nm = callee_method->code();

   if (callee_nm != NULL && !callee_nm->is_in_use()) {

     // Patch call site to C2I adapter if callee nmethod is deoptimized or unloaded.

     callee_nm = NULL;

   }

   nmethodLocker nl_callee(callee_nm);

 #ifdef ASSERT

   address dest_entry_point = callee_nm == NULL ? 0 : callee_nm->entry_point(); // used below

 #endif

   if (is_virtual) {

     assert(receiver.not_null() || invoke_code == Bytecodes::_invokehandle, "sanity check");

     bool static_bound = call_info.resolved_method()->can_be_statically_bound();

     KlassHandle h_klass(THREAD, invoke_code == Bytecodes::_invokehandle ? NULL : receiver->klass());

     CompiledIC::compute_monomorphic_entry(callee_method, h_klass,

                      is_optimized, static_bound, virtual_call_info,

                      CHECK_(methodHandle()));

   } else {

     // static call

     CompiledStaticCall::compute_entry(callee_method, static_call_info);

   }

   // grab lock, check for deoptimization and potentially patch caller

   {

     MutexLocker ml_patch(CompiledIC_lock);

     // Lock blocks for safepoint during which both nmethods can change state.

     // Now that we are ready to patch if the Method* was redefined then

     // don't update call site and let the caller retry.

     // Don't update call site if callee nmethod was unloaded or deoptimized.

     // Don't update call site if callee nmethod was replaced by an other nmethod

     // which may happen when multiply alive nmethod (tiered compilation)

     // will be supported.

     if (!callee_method->is_old() &&

         (callee_nm == NULL || callee_nm->is_in_use() && (callee_method->code() == callee_nm))) {

 #ifdef ASSERT

       // We must not try to patch to jump to an already unloaded method.

       if (dest_entry_point != 0) {

         CodeBlob* cb = CodeCache::find_blob(dest_entry_point);

         assert((cb != NULL) && cb->is_nmethod() && (((nmethod*)cb) == callee_nm),

                "should not call unloaded nmethod");

       }

 #endif

       if (is_virtual) {

         nmethod* nm = callee_nm;

         if (nm == NULL) CodeCache::find_blob(caller_frame.pc());

         CompiledIC* inline_cache = CompiledIC_before(caller_nm, caller_frame.pc());

         if (inline_cache->is_clean()) {

           inline_cache->set_to_monomorphic(virtual_call_info);

         }

       } else {

         CompiledStaticCall* ssc = compiledStaticCall_before(caller_frame.pc());

         if (ssc->is_clean()) ssc->set(static_call_info);

       }

     }

   } // unlock CompiledIC_lock

   return callee_method;

 }

 // Inline caches exist only in compiled code

 JRT_BLOCK_ENTRY(address, SharedRuntime::handle_wrong_method_ic_miss(JavaThread* thread))

 #ifdef ASSERT

   RegisterMap reg_map(thread, false);

   frame stub_frame = thread->last_frame();

   assert(stub_frame.is_runtime_frame(), "sanity check");

   frame caller_frame = stub_frame.sender(&reg_map);

   assert(!caller_frame.is_interpreted_frame() && !caller_frame.is_entry_frame(), "unexpected frame");

 #endif /* ASSERT */

   methodHandle callee_method;

   JRT_BLOCK

     callee_method = SharedRuntime::handle_ic_miss_helper(thread, CHECK_NULL);

     // Return Method* through TLS

     thread->set_vm_result_2(callee_method());

   JRT_BLOCK_END

   // return compiled code entry point after potential safepoints

   assert(callee_method->verified_code_entry() != NULL, " Jump to zero!");

   return callee_method->verified_code_entry();

 JRT_END

 // Handle call site that has been made non-entrant

 JRT_BLOCK_ENTRY(address, SharedRuntime::handle_wrong_method(JavaThread* thread))

   // 6243940 We might end up in here if the callee is deoptimized

   // as we race to call it.  We don't want to take a safepoint if

   // the caller was interpreted because the caller frame will look

   // interpreted to the stack walkers and arguments are now

   // "compiled" so it is much better to make this transition

   // invisible to the stack walking code. The i2c path will

   // place the callee method in the callee_target. It is stashed

   // there because if we try and find the callee by normal means a

   // safepoint is possible and have trouble gc'ing the compiled args.

   RegisterMap reg_map(thread, false);

   frame stub_frame = thread->last_frame();

   assert(stub_frame.is_runtime_frame(), "sanity check");

   frame caller_frame = stub_frame.sender(&reg_map);

   if (caller_frame.is_interpreted_frame() ||

       caller_frame.is_entry_frame()) {

     Method* callee = thread->callee_target();

     guarantee(callee != NULL && callee->is_method(), "bad handshake");

     thread->set_vm_result_2(callee);

     thread->set_callee_target(NULL);

     return callee->get_c2i_entry();

   }

   // Must be compiled to compiled path which is safe to stackwalk

   methodHandle callee_method;

   JRT_BLOCK

     // Force resolving of caller (if we called from compiled frame)

     callee_method = SharedRuntime::reresolve_call_site(thread, CHECK_NULL);

     thread->set_vm_result_2(callee_method());

   JRT_BLOCK_END

   // return compiled code entry point after potential safepoints

   assert(callee_method->verified_code_entry() != NULL, " Jump to zero!");

   return callee_method->verified_code_entry();

 JRT_END

 // Handle abstract method call

 JRT_BLOCK_ENTRY(address, SharedRuntime::handle_wrong_method_abstract(JavaThread* thread))

   return StubRoutines::throw_AbstractMethodError_entry();

 JRT_END

 // resolve a static call and patch code

 JRT_BLOCK_ENTRY(address, SharedRuntime::resolve_static_call_C(JavaThread *thread ))

   methodHandle callee_method;

   JRT_BLOCK

     callee_method = SharedRuntime::resolve_helper(thread, false, false, CHECK_NULL);

     thread->set_vm_result_2(callee_method());

   JRT_BLOCK_END

   // return compiled code entry point after potential safepoints

   assert(callee_method->verified_code_entry() != NULL, " Jump to zero!");

   return callee_method->verified_code_entry();

 JRT_END

 // resolve virtual call and update inline cache to monomorphic

 JRT_BLOCK_ENTRY(address, SharedRuntime::resolve_virtual_call_C(JavaThread *thread ))

   methodHandle callee_method;

   JRT_BLOCK

     callee_method = SharedRuntime::resolve_helper(thread, true, false, CHECK_NULL);

     thread->set_vm_result_2(callee_method());

   JRT_BLOCK_END

   // return compiled code entry point after potential safepoints

   assert(callee_method->verified_code_entry() != NULL, " Jump to zero!");

   return callee_method->verified_code_entry();

 JRT_END

 // Resolve a virtual call that can be statically bound (e.g., always

 // monomorphic, so it has no inline cache).  Patch code to resolved target.

 JRT_BLOCK_ENTRY(address, SharedRuntime::resolve_opt_virtual_call_C(JavaThread *thread))

   methodHandle callee_method;

   JRT_BLOCK

     callee_method = SharedRuntime::resolve_helper(thread, true, true, CHECK_NULL);

     thread->set_vm_result_2(callee_method());

   JRT_BLOCK_END

   // return compiled code entry point after potential safepoints

   assert(callee_method->verified_code_entry() != NULL, " Jump to zero!");

   return callee_method->verified_code_entry();

 JRT_END

 methodHandle SharedRuntime::handle_ic_miss_helper(JavaThread *thread, TRAPS) {

   ResourceMark rm(thread);

   CallInfo call_info;

   Bytecodes::Code bc;

   // receiver is NULL for static calls. An exception is thrown for NULL

   // receivers for non-static calls

   Handle receiver = find_callee_info(thread, bc, call_info,

                                      CHECK_(methodHandle()));

   // Compiler1 can produce virtual call sites that can actually be statically bound

   // If we fell thru to below we would think that the site was going megamorphic

   // when in fact the site can never miss. Worse because we'd think it was megamorphic

   // we'd try and do a vtable dispatch however methods that can be statically bound

   // don't have vtable entries (vtable_index < 0) and we'd blow up. So we force a

   // reresolution of the  call site (as if we did a handle_wrong_method and not an

   // plain ic_miss) and the site will be converted to an optimized virtual call site

   // never to miss again. I don't believe C2 will produce code like this but if it

   // did this would still be the correct thing to do for it too, hence no ifdef.

   //

   if (call_info.resolved_method()->can_be_statically_bound()) {

     methodHandle callee_method = SharedRuntime::reresolve_call_site(thread, CHECK_(methodHandle()));

     if (TraceCallFixup) {

       RegisterMap reg_map(thread, false);

       frame caller_frame = thread->last_frame().sender(&reg_map);

       ResourceMark rm(thread);

       tty->print("converting IC miss to reresolve (%s) call to", Bytecodes::name(bc));

       callee_method->print_short_name(tty);

       tty->print_cr(" from pc: " INTPTR_FORMAT, caller_frame.pc());

       tty->print_cr(" code: " INTPTR_FORMAT, callee_method->code());

     }

     return callee_method;

   }

   methodHandle callee_method = call_info.selected_method();

   bool should_be_mono = false;

 #ifndef PRODUCT

   Atomic::inc(&_ic_miss_ctr);

   // Statistics & Tracing

   if (TraceCallFixup) {

     ResourceMark rm(thread);

     tty->print("IC miss (%s) call to", Bytecodes::name(bc));

     callee_method->print_short_name(tty);

     tty->print_cr(" code: " INTPTR_FORMAT, callee_method->code());

   }

   if (ICMissHistogram) {

     MutexLocker m(VMStatistic_lock);

     RegisterMap reg_map(thread, false);

     frame f = thread->last_frame().real_sender(&reg_map);// skip runtime stub

     // produce statistics under the lock

     trace_ic_miss(f.pc());

   }

 #endif

   // install an event collector so that when a vtable stub is created the

   // profiler can be notified via a DYNAMIC_CODE_GENERATED event. The

   // event can't be posted when the stub is created as locks are held

   // - instead the event will be deferred until the event collector goes

   // out of scope.

   JvmtiDynamicCodeEventCollector event_collector;

   // Update inline cache to megamorphic. Skip update if we are called from interpreted.

   { MutexLocker ml_patch (CompiledIC_lock);

     RegisterMap reg_map(thread, false);

     frame caller_frame = thread->last_frame().sender(&reg_map);

     CodeBlob* cb = caller_frame.cb();

     if (cb->is_nmethod()) {

       CompiledIC* inline_cache = CompiledIC_before(((nmethod*)cb), caller_frame.pc());

       bool should_be_mono = false;

       if (inline_cache->is_optimized()) {

         if (TraceCallFixup) {

           ResourceMark rm(thread);

           tty->print("OPTIMIZED IC miss (%s) call to", Bytecodes::name(bc));

           callee_method->print_short_name(tty);

           tty->print_cr(" code: " INTPTR_FORMAT, callee_method->code());

         }

         should_be_mono = true;

       } else if (inline_cache->is_icholder_call()) {

         CompiledICHolder* ic_oop = inline_cache->cached_icholder();

         if ( ic_oop != NULL) {

           if (receiver()->klass() == ic_oop->holder_klass()) {

             // This isn't a real miss. We must have seen that compiled code

             // is now available and we want the call site converted to a

             // monomorphic compiled call site.

             // We can't assert for callee_method->code() != NULL because it

             // could have been deoptimized in the meantime

             if (TraceCallFixup) {

               ResourceMark rm(thread);

               tty->print("FALSE IC miss (%s) converting to compiled call to", Bytecodes::name(bc));

               callee_method->print_short_name(tty);

               tty->print_cr(" code: " INTPTR_FORMAT, callee_method->code());

             }

             should_be_mono = true;

           }

         }

       }

       if (should_be_mono) {

         // We have a path that was monomorphic but was going interpreted

         // and now we have (or had) a compiled entry. We correct the IC

         // by using a new icBuffer.

         CompiledICInfo info;

         KlassHandle receiver_klass(THREAD, receiver()->klass());

         inline_cache->compute_monomorphic_entry(callee_method,

                                                 receiver_klass,

                                                 inline_cache->is_optimized(),

                                                 false,

                                                 info, CHECK_(methodHandle()));

         inline_cache->set_to_monomorphic(info);

       } else if (!inline_cache->is_megamorphic() && !inline_cache->is_clean()) {

         // Potential change to megamorphic

         bool successful = inline_cache->set_to_megamorphic(&call_info, bc, CHECK_(methodHandle()));

         if (!successful) {

           inline_cache->set_to_clean();

         }

       } else {

         // Either clean or megamorphic

       }

     }

   } // Release CompiledIC_lock

   return callee_method;

 }

 //

 // Resets a call-site in compiled code so it will get resolved again.

 // This routines handles both virtual call sites, optimized virtual call

 // sites, and static call sites. Typically used to change a call sites

 // destination from compiled to interpreted.

 //

 methodHandle SharedRuntime::reresolve_call_site(JavaThread *thread, TRAPS) {

   ResourceMark rm(thread);

   RegisterMap reg_map(thread, false);

   frame stub_frame = thread->last_frame();

   assert(stub_frame.is_runtime_frame(), "must be a runtimeStub");

   frame caller = stub_frame.sender(&reg_map);

   // Do nothing if the frame isn't a live compiled frame.

   // nmethod could be deoptimized by the time we get here

   // so no update to the caller is needed.

   if (caller.is_compiled_frame() && !caller.is_deoptimized_frame()) {

     address pc = caller.pc();

     // Default call_addr is the location of the "basic" call.

     // Determine the address of the call we a reresolving. With

     // Inline Caches we will always find a recognizable call.

     // With Inline Caches disabled we may or may not find a

     // recognizable call. We will always find a call for static

     // calls and for optimized virtual calls. For vanilla virtual

     // calls it depends on the state of the UseInlineCaches switch.

     //

     // With Inline Caches disabled we can get here for a virtual call

     // for two reasons:

     //   1 - calling an abstract method. The vtable for abstract methods

     //       will run us thru handle_wrong_method and we will eventually

     //       end up in the interpreter to throw the ame.

     //   2 - a racing deoptimization. We could be doing a vanilla vtable

     //       call and between the time we fetch the entry address and

     //       we jump to it the target gets deoptimized. Similar to 1

     //       we will wind up in the interprter (thru a c2i with c2).

     //

     address call_addr = NULL;

     {

       // Get call instruction under lock because another thread may be

       // busy patching it.

       MutexLockerEx ml_patch(Patching_lock, Mutex::_no_safepoint_check_flag);

       // Location of call instruction

       if (NativeCall::is_call_before(pc)) {

         NativeCall *ncall = nativeCall_before(pc);

         call_addr = ncall->instruction_address();

       }

     }

     // Check for static or virtual call

     bool is_static_call = false;

     nmethod* caller_nm = CodeCache::find_nmethod(pc);

     // Make sure nmethod doesn't get deoptimized and removed until

     // this is done with it.

     // CLEANUP - with lazy deopt shouldn't need this lock

     nmethodLocker nmlock(caller_nm);

     if (call_addr != NULL) {

       RelocIterator iter(caller_nm, call_addr, call_addr+1);

       int ret = iter.next(); // Get item

       if (ret) {

         assert(iter.addr() == call_addr, "must find call");

         if (iter.type() == relocInfo::static_call_type) {

           is_static_call = true;

         } else {

           assert(iter.type() == relocInfo::virtual_call_type ||

                  iter.type() == relocInfo::opt_virtual_call_type

                 , "unexpected relocInfo. type");

         }

       } else {

         assert(!UseInlineCaches, "relocation info. must exist for this address");

       }

       // Cleaning the inline cache will force a new resolve. This is more robust

       // than directly setting it to the new destination, since resolving of calls

       // is always done through the same code path. (experience shows that it

       // leads to very hard to track down bugs, if an inline cache gets updated

       // to a wrong method). It should not be performance critical, since the

       // resolve is only done once.

       MutexLocker ml(CompiledIC_lock);

       if (is_static_call) {

         CompiledStaticCall* ssc= compiledStaticCall_at(call_addr);

         ssc->set_to_clean();

       } else {

         // compiled, dispatched call (which used to call an interpreted method)

         CompiledIC* inline_cache = CompiledIC_at(caller_nm, call_addr);

         inline_cache->set_to_clean();

       }

     }

   }

   methodHandle callee_method = find_callee_method(thread, CHECK_(methodHandle()));

 #ifndef PRODUCT

   Atomic::inc(&_wrong_method_ctr);

   if (TraceCallFixup) {

     ResourceMark rm(thread);

     tty->print("handle_wrong_method reresolving call to");

     callee_method->print_short_name(tty);

     tty->print_cr(" code: " INTPTR_FORMAT, callee_method->code());

   }

 #endif

   return callee_method;

 }

 #ifdef ASSERT

 void SharedRuntime::check_member_name_argument_is_last_argument(methodHandle method,

                                                                 const BasicType* sig_bt,

                                                                 const VMRegPair* regs) {

   ResourceMark rm;

   const int total_args_passed = method->size_of_parameters();

   const VMRegPair*    regs_with_member_name = regs;

         VMRegPair* regs_without_member_name = NEW_RESOURCE_ARRAY(VMRegPair, total_args_passed - 1);

   const int member_arg_pos = total_args_passed - 1;

   assert(member_arg_pos >= 0 && member_arg_pos < total_args_passed, "oob");

   assert(sig_bt[member_arg_pos] == T_OBJECT, "dispatch argument must be an object");

   const bool is_outgoing = method->is_method_handle_intrinsic();

   int comp_args_on_stack = java_calling_convention(sig_bt, regs_without_member_name, total_args_passed - 1, is_outgoing);

   for (int i = 0; i < member_arg_pos; i++) {

     VMReg a =    regs_with_member_name[i].first();

     VMReg b = regs_without_member_name[i].first();

     assert(a->value() == b->value(), err_msg_res("register allocation mismatch: a=%d, b=%d", a->value(), b->value()));

   }

   assert(regs_with_member_name[member_arg_pos].first()->is_valid(), "bad member arg");

 }

 #endif

 // ---------------------------------------------------------------------------

 // We are calling the interpreter via a c2i. Normally this would mean that

 // we were called by a compiled method. However we could have lost a race

 // where we went int -> i2c -> c2i and so the caller could in fact be

 // interpreted. If the caller is compiled we attempt to patch the caller

 // so he no longer calls into the interpreter.

 IRT_LEAF(void, SharedRuntime::fixup_callers_callsite(Method* method, address caller_pc))

   Method* moop(method);

   address entry_point = moop->from_compiled_entry();

   // It's possible that deoptimization can occur at a call site which hasn't

   // been resolved yet, in which case this function will be called from

   // an nmethod that has been patched for deopt and we can ignore the

   // request for a fixup.

   // Also it is possible that we lost a race in that from_compiled_entry

   // is now back to the i2c in that case we don't need to patch and if

   // we did we'd leap into space because the callsite needs to use

   // "to interpreter" stub in order to load up the Method*. Don't

   // ask me how I know this...

   CodeBlob* cb = CodeCache::find_blob(caller_pc);

   if (cb == NULL || !cb->is_nmethod() || entry_point == moop->get_c2i_entry()) {

     return;

   }

   // The check above makes sure this is a nmethod.

   nmethod* nm = cb->as_nmethod_or_null();

   assert(nm, "must be");

   // Get the return PC for the passed caller PC.

   address return_pc = caller_pc + frame::pc_return_offset;

   // There is a benign race here. We could be attempting to patch to a compiled

   // entry point at the same time the callee is being deoptimized. If that is

   // the case then entry_point may in fact point to a c2i and we'd patch the

   // call site with the same old data. clear_code will set code() to NULL

   // at the end of it. If we happen to see that NULL then we can skip trying

   // to patch. If we hit the window where the callee has a c2i in the

   // from_compiled_entry and the NULL isn't present yet then we lose the race

   // and patch the code with the same old data. Asi es la vida.

   if (moop->code() == NULL) return;

   if (nm->is_in_use()) {

     // Expect to find a native call there (unless it was no-inline cache vtable dispatch)

     MutexLockerEx ml_patch(Patching_lock, Mutex::_no_safepoint_check_flag);

     if (NativeCall::is_call_before(return_pc)) {

       NativeCall *call = nativeCall_before(return_pc);

       //

       // bug 6281185. We might get here after resolving a call site to a vanilla

       // virtual call. Because the resolvee uses the verified entry it may then

       // see compiled code and attempt to patch the site by calling us. This would

       // then incorrectly convert the call site to optimized and its downhill from

       // there. If you're lucky you'll get the assert in the bugid, if not you've

       // just made a call site that could be megamorphic into a monomorphic site

       // for the rest of its life! Just another racing bug in the life of

       // fixup_callers_callsite ...

       //

       RelocIterator iter(nm, call->instruction_address(), call->next_instruction_address());

       iter.next();

       assert(iter.has_current(), "must have a reloc at java call site");

       relocInfo::relocType typ = iter.reloc()->type();

       if ( typ != relocInfo::static_call_type &&

            typ != relocInfo::opt_virtual_call_type &&

            typ != relocInfo::static_stub_type) {

         return;

       }

       address destination = call->destination();

       if (destination != entry_point) {

         CodeBlob* callee = CodeCache::find_blob(destination);

         // callee == cb seems weird. It means calling interpreter thru stub.

         if (callee != NULL && (callee == cb || callee->is_adapter_blob())) {

           // static call or optimized virtual

           if (TraceCallFixup) {

             tty->print("fixup callsite           at " INTPTR_FORMAT " to compiled code for", caller_pc);

             moop->print_short_name(tty);

             tty->print_cr(" to " INTPTR_FORMAT, entry_point);

           }

           call->set_destination_mt_safe(entry_point);

         } else {

           if (TraceCallFixup) {

             tty->print("failed to fixup callsite at " INTPTR_FORMAT " to compiled code for", caller_pc);

             moop->print_short_name(tty);

             tty->print_cr(" to " INTPTR_FORMAT, entry_point);

           }

           // assert is too strong could also be resolve destinations.

           // assert(InlineCacheBuffer::contains(destination) || VtableStubs::contains(destination), "must be");

         }

       } else {

           if (TraceCallFixup) {

             tty->print("already patched callsite at " INTPTR_FORMAT " to compiled code for", caller_pc);

             moop->print_short_name(tty);

             tty->print_cr(" to " INTPTR_FORMAT, entry_point);

           }

       }

     }

   }

 IRT_END

 // same as JVM_Arraycopy, but called directly from compiled code

 JRT_ENTRY(void, SharedRuntime::slow_arraycopy_C(oopDesc* src,  jint src_pos,

                                                 oopDesc* dest, jint dest_pos,

                                                 jint length,

                                                 JavaThread* thread)) {

 #ifndef PRODUCT

   _slow_array_copy_ctr++;

 #endif

   // Check if we have null pointers

   if (src == NULL || dest == NULL) {

     THROW(vmSymbols::java_lang_NullPointerException());

   }

   // Do the copy.  The casts to arrayOop are necessary to the copy_array API,

   // even though the copy_array API also performs dynamic checks to ensure

   // that src and dest are truly arrays (and are conformable).

   // The copy_array mechanism is awkward and could be removed, but

   // the compilers don't call this function except as a last resort,

   // so it probably doesn't matter.

   src->klass()->copy_array((arrayOopDesc*)src,  src_pos,

                                         (arrayOopDesc*)dest, dest_pos,

                                         length, thread);

 }

 JRT_END

 char* SharedRuntime::generate_class_cast_message(

     JavaThread* thread, const char* objName) {

   // Get target class name from the checkcast instruction

   vframeStream vfst(thread, true);

   assert(!vfst.at_end(), "Java frame must exist");

   Bytecode_checkcast cc(vfst.method(), vfst.method()->bcp_from(vfst.bci()));

   Klass* targetKlass = vfst.method()->constants()->klass_at(

     cc.index(), thread);

   return generate_class_cast_message(objName, targetKlass->external_name());

 }

 char* SharedRuntime::generate_class_cast_message(

     const char* objName, const char* targetKlassName, const char* desc) {

   size_t msglen = strlen(objName) + strlen(desc) + strlen(targetKlassName) + 1;

   char* message = NEW_RESOURCE_ARRAY(char, msglen);

   if (NULL == message) {

     // Shouldn't happen, but don't cause even more problems if it does

     message = const_cast<char*>(objName);

   } else {

     jio_snprintf(message, msglen, "%s%s%s", objName, desc, targetKlassName);

   }

   return message;

 }

 JRT_LEAF(void, SharedRuntime::reguard_yellow_pages())

   (void) JavaThread::current()->reguard_stack();

 JRT_END

 // Handles the uncommon case in locking, i.e., contention or an inflated lock.

 #ifndef PRODUCT

 int SharedRuntime::_monitor_enter_ctr=0;

 #endif

 JRT_ENTRY_NO_ASYNC(void, SharedRuntime::complete_monitor_locking_C(oopDesc* _obj, BasicLock* lock, JavaThread* thread))

   oop obj(_obj);

 #ifndef PRODUCT

   _monitor_enter_ctr++;             // monitor enter slow

 #endif

   if (PrintBiasedLockingStatistics) {

     Atomic::inc(BiasedLocking::slow_path_entry_count_addr());

   }

   Handle h_obj(THREAD, obj);

   if (UseBiasedLocking) {

     // Retry fast entry if bias is revoked to avoid unnecessary inflation

     ObjectSynchronizer::fast_enter(h_obj, lock, true, CHECK);

   } else {

     ObjectSynchronizer::slow_enter(h_obj, lock, CHECK);

   }

   assert(!HAS_PENDING_EXCEPTION, "Should have no exception here");

 JRT_END

 #ifndef PRODUCT

 int SharedRuntime::_monitor_exit_ctr=0;

 #endif

 // Handles the uncommon cases of monitor unlocking in compiled code

 JRT_LEAF(void, SharedRuntime::complete_monitor_unlocking_C(oopDesc* _obj, BasicLock* lock))

    oop obj(_obj);

 #ifndef PRODUCT

   _monitor_exit_ctr++;              // monitor exit slow

 #endif

   Thread* THREAD = JavaThread::current();

   // I'm not convinced we need the code contained by MIGHT_HAVE_PENDING anymore

   // testing was unable to ever fire the assert that guarded it so I have removed it.

   assert(!HAS_PENDING_EXCEPTION, "Do we need code below anymore?");

 #undef MIGHT_HAVE_PENDING

 #ifdef MIGHT_HAVE_PENDING

   // Save and restore any pending_exception around the exception mark.

   // While the slow_exit must not throw an exception, we could come into

   // this routine with one set.

   oop pending_excep = NULL;

   const char* pending_file;

   int pending_line;

   if (HAS_PENDING_EXCEPTION) {

     pending_excep = PENDING_EXCEPTION;

     pending_file  = THREAD->exception_file();

     pending_line  = THREAD->exception_line();

     CLEAR_PENDING_EXCEPTION;

   }

 #endif /* MIGHT_HAVE_PENDING */

   {

     // Exit must be non-blocking, and therefore no exceptions can be thrown.

     EXCEPTION_MARK;

     ObjectSynchronizer::slow_exit(obj, lock, THREAD);

   }

 #ifdef MIGHT_HAVE_PENDING

   if (pending_excep != NULL) {

     THREAD->set_pending_exception(pending_excep, pending_file, pending_line);

   }

 #endif /* MIGHT_HAVE_PENDING */

 JRT_END

 #ifndef PRODUCT

 void SharedRuntime::print_statistics() {

   ttyLocker ttyl;

   if (xtty != NULL)  xtty->head("statistics type='SharedRuntime'");

   if (_monitor_enter_ctr ) tty->print_cr("%5d monitor enter slow",  _monitor_enter_ctr);

   if (_monitor_exit_ctr  ) tty->print_cr("%5d monitor exit slow",   _monitor_exit_ctr);

   if (_throw_null_ctr) tty->print_cr("%5d implicit null throw", _throw_null_ctr);

   SharedRuntime::print_ic_miss_histogram();

   if (CountRemovableExceptions) {

     if (_nof_removable_exceptions > 0) {

       Unimplemented(); // this counter is not yet incremented

       tty->print_cr("Removable exceptions: %d", _nof_removable_exceptions);

     }

   }

   // Dump the JRT_ENTRY counters

   if( _new_instance_ctr ) tty->print_cr("%5d new instance requires GC", _new_instance_ctr);

   if( _new_array_ctr ) tty->print_cr("%5d new array requires GC", _new_array_ctr);

   if( _multi1_ctr ) tty->print_cr("%5d multianewarray 1 dim", _multi1_ctr);

   if( _multi2_ctr ) tty->print_cr("%5d multianewarray 2 dim", _multi2_ctr);

   if( _multi3_ctr ) tty->print_cr("%5d multianewarray 3 dim", _multi3_ctr);

   if( _multi4_ctr ) tty->print_cr("%5d multianewarray 4 dim", _multi4_ctr);

   if( _multi5_ctr ) tty->print_cr("%5d multianewarray 5 dim", _multi5_ctr);

   tty->print_cr("%5d inline cache miss in compiled", _ic_miss_ctr );

   tty->print_cr("%5d wrong method", _wrong_method_ctr );

   tty->print_cr("%5d unresolved static call site", _resolve_static_ctr );

   tty->print_cr("%5d unresolved virtual call site", _resolve_virtual_ctr );

   tty->print_cr("%5d unresolved opt virtual call site", _resolve_opt_virtual_ctr );

   if( _mon_enter_stub_ctr ) tty->print_cr("%5d monitor enter stub", _mon_enter_stub_ctr );

   if( _mon_exit_stub_ctr ) tty->print_cr("%5d monitor exit stub", _mon_exit_stub_ctr );

   if( _mon_enter_ctr ) tty->print_cr("%5d monitor enter slow", _mon_enter_ctr );

   if( _mon_exit_ctr ) tty->print_cr("%5d monitor exit slow", _mon_exit_ctr );

   if( _partial_subtype_ctr) tty->print_cr("%5d slow partial subtype", _partial_subtype_ctr );

   if( _jbyte_array_copy_ctr ) tty->print_cr("%5d byte array copies", _jbyte_array_copy_ctr );

   if( _jshort_array_copy_ctr ) tty->print_cr("%5d short array copies", _jshort_array_copy_ctr );

   if( _jint_array_copy_ctr ) tty->print_cr("%5d int array copies", _jint_array_copy_ctr );

   if( _jlong_array_copy_ctr ) tty->print_cr("%5d long array copies", _jlong_array_copy_ctr );

   if( _oop_array_copy_ctr ) tty->print_cr("%5d oop array copies", _oop_array_copy_ctr );

   if( _checkcast_array_copy_ctr ) tty->print_cr("%5d checkcast array copies", _checkcast_array_copy_ctr );

   if( _unsafe_array_copy_ctr ) tty->print_cr("%5d unsafe array copies", _unsafe_array_copy_ctr );

   if( _generic_array_copy_ctr ) tty->print_cr("%5d generic array copies", _generic_array_copy_ctr );

   if( _slow_array_copy_ctr ) tty->print_cr("%5d slow array copies", _slow_array_copy_ctr );

   if( _find_handler_ctr ) tty->print_cr("%5d find exception handler", _find_handler_ctr );

   if( _rethrow_ctr ) tty->print_cr("%5d rethrow handler", _rethrow_ctr );

   AdapterHandlerLibrary::print_statistics();

   if (xtty != NULL)  xtty->tail("statistics");

 }

 inline double percent(int x, int y) {

   return 100.0 * x / MAX2(y, 1);

 }

 class MethodArityHistogram {

  public:

   enum { MAX_ARITY = 256 };

  private:

   static int _arity_histogram[MAX_ARITY];     // histogram of #args

   static int _size_histogram[MAX_ARITY];      // histogram of arg size in words

   static int _max_arity;                      // max. arity seen

   static int _max_size;                       // max. arg size seen

   static void add_method_to_histogram(nmethod* nm) {

     Method* m = nm->method();

     ArgumentCount args(m->signature());

     int arity   = args.size() + (m->is_static() ? 0 : 1);

     int argsize = m->size_of_parameters();

     arity   = MIN2(arity, MAX_ARITY-1);

     argsize = MIN2(argsize, MAX_ARITY-1);

     int count = nm->method()->compiled_invocation_count();

     _arity_histogram[arity]  += count;

     _size_histogram[argsize] += count;

     _max_arity = MAX2(_max_arity, arity);

     _max_size  = MAX2(_max_size, argsize);

   }

   void print_histogram_helper(int n, int* histo, const char* name) {

     const int N = MIN2(5, n);

     tty->print_cr("\nHistogram of call arity (incl. rcvr, calls to compiled methods only):");

     double sum = 0;

     double weighted_sum = 0;

     int i;

     for (i = 0; i <= n; i++) { sum += histo[i]; weighted_sum += i*histo[i]; }

     double rest = sum;

     double percent = sum / 100;

     for (i = 0; i <= N; i++) {

       rest -= histo[i];

       tty->print_cr("%4d: %7d (%5.1f%%)", i, histo[i], histo[i] / percent);

     }

     tty->print_cr("rest: %7d (%5.1f%%))", (int)rest, rest / percent);

     tty->print_cr("(avg. %s = %3.1f, max = %d)", name, weighted_sum / sum, n);

   }

   void print_histogram() {

     tty->print_cr("\nHistogram of call arity (incl. rcvr, calls to compiled methods only):");

     print_histogram_helper(_max_arity, _arity_histogram, "arity");

     tty->print_cr("\nSame for parameter size (in words):");

     print_histogram_helper(_max_size, _size_histogram, "size");

     tty->cr();

   }

  public:

   MethodArityHistogram() {

     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);

     _max_arity = _max_size = 0;

     for (int i = 0; i < MAX_ARITY; i++) _arity_histogram[i] = _size_histogram [i] = 0;

     CodeCache::nmethods_do(add_method_to_histogram);

     print_histogram();

   }

 };

 int MethodArityHistogram::_arity_histogram[MethodArityHistogram::MAX_ARITY];

 int MethodArityHistogram::_size_histogram[MethodArityHistogram::MAX_ARITY];

 int MethodArityHistogram::_max_arity;

 int MethodArityHistogram::_max_size;

 void SharedRuntime::print_call_statistics(int comp_total) {

   tty->print_cr("Calls from compiled code:");

   int total  = _nof_normal_calls + _nof_interface_calls + _nof_static_calls;

   int mono_c = _nof_normal_calls - _nof_optimized_calls - _nof_megamorphic_calls;

   int mono_i = _nof_interface_calls - _nof_optimized_interface_calls - _nof_megamorphic_interface_calls;

   tty->print_cr("\t%9d   (%4.1f%%) total non-inlined   ", total, percent(total, total));

   tty->print_cr("\t%9d   (%4.1f%%) virtual calls       ", _nof_normal_calls, percent(_nof_normal_calls, total));

   tty->print_cr("\t  %9d  (%3.0f%%)   inlined          ", _nof_inlined_calls, percent(_nof_inlined_calls, _nof_normal_calls));

   tty->print_cr("\t  %9d  (%3.0f%%)   optimized        ", _nof_optimized_calls, percent(_nof_optimized_calls, _nof_normal_calls));

   tty->print_cr("\t  %9d  (%3.0f%%)   monomorphic      ", mono_c, percent(mono_c, _nof_normal_calls));

   tty->print_cr("\t  %9d  (%3.0f%%)   megamorphic      ", _nof_megamorphic_calls, percent(_nof_megamorphic_calls, _nof_normal_calls));

   tty->print_cr("\t%9d   (%4.1f%%) interface calls     ", _nof_interface_calls, percent(_nof_interface_calls, total));

   tty->print_cr("\t  %9d  (%3.0f%%)   inlined          ", _nof_inlined_interface_calls, percent(_nof_inlined_interface_calls, _nof_interface_calls));

   tty->print_cr("\t  %9d  (%3.0f%%)   optimized        ", _nof_optimized_interface_calls, percent(_nof_optimized_interface_calls, _nof_interface_calls));

   tty->print_cr("\t  %9d  (%3.0f%%)   monomorphic      ", mono_i, percent(mono_i, _nof_interface_calls));

   tty->print_cr("\t  %9d  (%3.0f%%)   megamorphic      ", _nof_megamorphic_interface_calls, percent(_nof_megamorphic_interface_calls, _nof_interface_calls));

   tty->print_cr("\t%9d   (%4.1f%%) static/special calls", _nof_static_calls, percent(_nof_static_calls, total));

   tty->print_cr("\t  %9d  (%3.0f%%)   inlined          ", _nof_inlined_static_calls, percent(_nof_inlined_static_calls, _nof_static_calls));

   tty->cr();

   tty->print_cr("Note 1: counter updates are not MT-safe.");

   tty->print_cr("Note 2: %% in major categories are relative to total non-inlined calls;");

   tty->print_cr("        %% in nested categories are relative to their category");

   tty->print_cr("        (and thus add up to more than 100%% with inlining)");

   tty->cr();

   MethodArityHistogram h;

 }

 #endif

 // A simple wrapper class around the calling convention information

 // that allows sharing of adapters for the same calling convention.

 class AdapterFingerPrint : public CHeapObj<mtCode> {

  private:

   enum {

     _basic_type_bits = 4,

     _basic_type_mask = right_n_bits(_basic_type_bits),

     _basic_types_per_int = BitsPerInt / _basic_type_bits,

     _compact_int_count = 3

   };

   // TO DO:  Consider integrating this with a more global scheme for compressing signatures.

   // For now, 4 bits per components (plus T_VOID gaps after double/long) is not excessive.

   union {

     int  _compact[_compact_int_count];

     int* _fingerprint;

   } _value;

   int _length; // A negative length indicates the fingerprint is in the compact form,

                // Otherwise _value._fingerprint is the array.

   // Remap BasicTypes that are handled equivalently by the adapters.

   // These are correct for the current system but someday it might be

   // necessary to make this mapping platform dependent.

   static int adapter_encoding(BasicType in) {

     switch(in) {

       case T_BOOLEAN:

       case T_BYTE:

       case T_SHORT:

       case T_CHAR:

         // There are all promoted to T_INT in the calling convention

         return T_INT;

       case T_OBJECT:

       case T_ARRAY:

         // In other words, we assume that any register good enough for

         // an int or long is good enough for a managed pointer.

 #ifdef _LP64

         return T_LONG;

 #else

         return T_INT;

 #endif

       case T_INT:

       case T_LONG:

       case T_FLOAT:

       case T_DOUBLE:

       case T_VOID:

         return in;

       default:

         ShouldNotReachHere();

         return T_CONFLICT;

     }

   }

  public:

   AdapterFingerPrint(int total_args_passed, BasicType* sig_bt) {

     // The fingerprint is based on the BasicType signature encoded

     // into an array of ints with eight entries per int.

     int* ptr;

     int len = (total_args_passed + (_basic_types_per_int-1)) / _basic_types_per_int;

     if (len <= _compact_int_count) {

       assert(_compact_int_count == 3, "else change next line");

       _value._compact[0] = _value._compact[1] = _value._compact[2] = 0;

       // Storing the signature encoded as signed chars hits about 98%

       // of the time.

       _length = -len;

       ptr = _value._compact;

     } else {

       _length = len;

       _value._fingerprint = NEW_C_HEAP_ARRAY(int, _length, mtCode);

       ptr = _value._fingerprint;

     }

     // Now pack the BasicTypes with 8 per int

     int sig_index = 0;

     for (int index = 0; index < len; index++) {

       int value = 0;

       for (int byte = 0; byte < _basic_types_per_int; byte++) {

         int bt = ((sig_index < total_args_passed)

                   ? adapter_encoding(sig_bt[sig_index++])

                   : 0);

         assert((bt & _basic_type_mask) == bt, "must fit in 4 bits");

         value = (value << _basic_type_bits) | bt;

       }

       ptr[index] = value;

     }

   }

   ~AdapterFingerPrint() {

     if (_length > 0) {

       FREE_C_HEAP_ARRAY(int, _value._fingerprint, mtCode);

     }

   }

   int value(int index) {

     if (_length < 0) {

       return _value._compact[index];

     }

     return _value._fingerprint[index];

   }

   int length() {

     if (_length < 0) return -_length;

     return _length;

   }

   bool is_compact() {

     return _length <= 0;

   }

   unsigned int compute_hash() {

     int hash = 0;

     for (int i = 0; i < length(); i++) {

       int v = value(i);

       hash = (hash << 8) ^ v ^ (hash >> 5);

     }

     return (unsigned int)hash;

   }

   const char* as_string() {

     stringStream st;

     st.print("0x");

     for (int i = 0; i < length(); i++) {

       st.print("%08x", value(i));

     }

     return st.as_string();

   }

   bool equals(AdapterFingerPrint* other) {

     if (other->_length != _length) {

       return false;

     }

     if (_length < 0) {

       assert(_compact_int_count == 3, "else change next line");

       return _value._compact[0] == other->_value._compact[0] &&

              _value._compact[1] == other->_value._compact[1] &&

              _value._compact[2] == other->_value._compact[2];

     } else {

       for (int i = 0; i < _length; i++) {

         if (_value._fingerprint[i] != other->_value._fingerprint[i]) {

           return false;

         }

       }

     }

     return true;

   }

 };

 // A hashtable mapping from AdapterFingerPrints to AdapterHandlerEntries

 class AdapterHandlerTable : public BasicHashtable<mtCode> {

   friend class AdapterHandlerTableIterator;

  private:

 #ifndef PRODUCT

   static int _lookups; // number of calls to lookup

   static int _buckets; // number of buckets checked

   static int _equals;  // number of buckets checked with matching hash

   static int _hits;    // number of successful lookups

   static int _compact; // number of equals calls with compact signature

 #endif

   AdapterHandlerEntry* bucket(int i) {

     return (AdapterHandlerEntry*)BasicHashtable<mtCode>::bucket(i);

   }

  public:

   AdapterHandlerTable()

     : BasicHashtable<mtCode>(293, sizeof(AdapterHandlerEntry)) { }

   // Create a new entry suitable for insertion in the table

   AdapterHandlerEntry* new_entry(AdapterFingerPrint* fingerprint, address i2c_entry, address c2i_entry, address c2i_unverified_entry) {

     AdapterHandlerEntry* entry = (AdapterHandlerEntry*)BasicHashtable<mtCode>::new_entry(fingerprint->compute_hash());

     entry->init(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);

     return entry;

   }

   // Insert an entry into the table

   void add(AdapterHandlerEntry* entry) {

     int index = hash_to_index(entry->hash());

     add_entry(index, entry);

   }

   void free_entry(AdapterHandlerEntry* entry) {

     entry->deallocate();

     BasicHashtable<mtCode>::free_entry(entry);

   }

   // Find a entry with the same fingerprint if it exists

   AdapterHandlerEntry* lookup(int total_args_passed, BasicType* sig_bt) {

     NOT_PRODUCT(_lookups++);

     AdapterFingerPrint fp(total_args_passed, sig_bt);

     unsigned int hash = fp.compute_hash();

     int index = hash_to_index(hash);

     for (AdapterHandlerEntry* e = bucket(index); e != NULL; e = e->next()) {

       NOT_PRODUCT(_buckets++);

       if (e->hash() == hash) {

         NOT_PRODUCT(_equals++);

         if (fp.equals(e->fingerprint())) {

 #ifndef PRODUCT

           if (fp.is_compact()) _compact++;

           _hits++;

 #endif

           return e;

         }

       }

     }

     return NULL;

   }

 #ifndef PRODUCT

   void print_statistics() {

     ResourceMark rm;

     int longest = 0;

     int empty = 0;

     int total = 0;

     int nonempty = 0;

     for (int index = 0; index < table_size(); index++) {

       int count = 0;

       for (AdapterHandlerEntry* e = bucket(index); e != NULL; e = e->next()) {

         count++;

       }

       if (count != 0) nonempty++;

       if (count == 0) empty++;

       if (count > longest) longest = count;

       total += count;

     }

     tty->print_cr("AdapterHandlerTable: empty %d longest %d total %d average %f",

                   empty, longest, total, total / (double)nonempty);

     tty->print_cr("AdapterHandlerTable: lookups %d buckets %d equals %d hits %d compact %d",

                   _lookups, _buckets, _equals, _hits, _compact);

   }

 #endif

 };

 #ifndef PRODUCT

 int AdapterHandlerTable::_lookups;

 int AdapterHandlerTable::_buckets;

 int AdapterHandlerTable::_equals;

 int AdapterHandlerTable::_hits;

 int AdapterHandlerTable::_compact;

 #endif

 class AdapterHandlerTableIterator : public StackObj {

  private:

   AdapterHandlerTable* _table;

   int _index;

   AdapterHandlerEntry* _current;

   void scan() {

     while (_index < _table->table_size()) {

       AdapterHandlerEntry* a = _table->bucket(_index);

       _index++;

       if (a != NULL) {

         _current = a;

         return;

       }

     }

   }

  public:

   AdapterHandlerTableIterator(AdapterHandlerTable* table): _table(table), _index(0), _current(NULL) {

     scan();

   }

   bool has_next() {

     return _current != NULL;

   }

   AdapterHandlerEntry* next() {

     if (_current != NULL) {

       AdapterHandlerEntry* result = _current;

       _current = _current->next();

       if (_current == NULL) scan();

       return result;

     } else {

       return NULL;

     }

   }

 };

 // ---------------------------------------------------------------------------

 // Implementation of AdapterHandlerLibrary

 AdapterHandlerTable* AdapterHandlerLibrary::_adapters = NULL;

 AdapterHandlerEntry* AdapterHandlerLibrary::_abstract_method_handler = NULL;

 const int AdapterHandlerLibrary_size = 16*K;

 BufferBlob* AdapterHandlerLibrary::_buffer = NULL;

 BufferBlob* AdapterHandlerLibrary::buffer_blob() {

   // Should be called only when AdapterHandlerLibrary_lock is active.

   if (_buffer == NULL) // Initialize lazily

       _buffer = BufferBlob::create("adapters", AdapterHandlerLibrary_size);

   return _buffer;

 }

 void AdapterHandlerLibrary::initialize() {

   if (_adapters != NULL) return;

   _adapters = new AdapterHandlerTable();

   // Create a special handler for abstract methods.  Abstract methods

   // are never compiled so an i2c entry is somewhat meaningless, but

   // throw AbstractMethodError just in case.

   // Pass wrong_method_abstract for the c2i transitions to return

   // AbstractMethodError for invalid invocations.

   address wrong_method_abstract = SharedRuntime::get_handle_wrong_method_abstract_stub();

   _abstract_method_handler = AdapterHandlerLibrary::new_entry(new AdapterFingerPrint(0, NULL),

                                                               StubRoutines::throw_AbstractMethodError_entry(),

                                                               wrong_method_abstract, wrong_method_abstract);

 }

 AdapterHandlerEntry* AdapterHandlerLibrary::new_entry(AdapterFingerPrint* fingerprint,

                                                       address i2c_entry,

                                                       address c2i_entry,

                                                       address c2i_unverified_entry) {

   return _adapters->new_entry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);

 }

 AdapterHandlerEntry* AdapterHandlerLibrary::get_adapter(methodHandle method) {

   // Use customized signature handler.  Need to lock around updates to

   // the AdapterHandlerTable (it is not safe for concurrent readers

   // and a single writer: this could be fixed if it becomes a

   // problem).

   // Get the address of the ic_miss handlers before we grab the

   // AdapterHandlerLibrary_lock. This fixes bug 6236259 which

   // was caused by the initialization of the stubs happening

   // while we held the lock and then notifying jvmti while

   // holding it. This just forces the initialization to be a little

   // earlier.

   address ic_miss = SharedRuntime::get_ic_miss_stub();

   assert(ic_miss != NULL, "must have handler");

   ResourceMark rm;

   NOT_PRODUCT(int insts_size);

   AdapterBlob* new_adapter = NULL;

   AdapterHandlerEntry* entry = NULL;

   AdapterFingerPrint* fingerprint = NULL;

   {

     MutexLocker mu(AdapterHandlerLibrary_lock);

     // make sure data structure is initialized

     initialize();

     if (method->is_abstract()) {

       return _abstract_method_handler;

     }

     // Fill in the signature array, for the calling-convention call.

     int total_args_passed = method->size_of_parameters(); // All args on stack

     BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_args_passed);

     VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, total_args_passed);

     int i = 0;

     if (!method->is_static())  // Pass in receiver first

       sig_bt[i++] = T_OBJECT;

     for (SignatureStream ss(method->signature()); !ss.at_return_type(); ss.next()) {

       sig_bt[i++] = ss.type();  // Collect remaining bits of signature

       if (ss.type() == T_LONG || ss.type() == T_DOUBLE)

         sig_bt[i++] = T_VOID;   // Longs & doubles take 2 Java slots

     }

     assert(i == total_args_passed, "");

     // Lookup method signature's fingerprint

     entry = _adapters->lookup(total_args_passed, sig_bt);

 #ifdef ASSERT

     AdapterHandlerEntry* shared_entry = NULL;

     // Start adapter sharing verification only after the VM is booted.

     if (VerifyAdapterSharing && (entry != NULL)) {

       shared_entry = entry;

       entry = NULL;

     }

 #endif

     if (entry != NULL) {

       return entry;

     }

     // Get a description of the compiled java calling convention and the largest used (VMReg) stack slot usage

     int comp_args_on_stack = SharedRuntime::java_calling_convention(sig_bt, regs, total_args_passed, false);

     // Make a C heap allocated version of the fingerprint to store in the adapter

     fingerprint = new AdapterFingerPrint(total_args_passed, sig_bt);

     // StubRoutines::code2() is initialized after this function can be called. As a result,

     // VerifyAdapterCalls and VerifyAdapterSharing can fail if we re-use code that generated

     // prior to StubRoutines::code2() being set. Checks refer to checks generated in an I2C

     // stub that ensure that an I2C stub is called from an interpreter frame.

     bool contains_all_checks = StubRoutines::code2() != NULL;

     // Create I2C & C2I handlers

     BufferBlob* buf = buffer_blob(); // the temporary code buffer in CodeCache

     if (buf != NULL) {

       CodeBuffer buffer(buf);

       short buffer_locs[20];

       buffer.insts()->initialize_shared_locs((relocInfo*)buffer_locs,

                                              sizeof(buffer_locs)/sizeof(relocInfo));

       MacroAssembler _masm(&buffer);

       entry = SharedRuntime::generate_i2c2i_adapters(&_masm,

                                                      total_args_passed,

                                                      comp_args_on_stack,

                                                      sig_bt,

                                                      regs,

                                                      fingerprint);

 #ifdef ASSERT

       if (VerifyAdapterSharing) {

         if (shared_entry != NULL) {

           assert(shared_entry->compare_code(buf->code_begin(), buffer.insts_size()), "code must match");

           // Release the one just created and return the original

           _adapters->free_entry(entry);

           return shared_entry;

         } else  {

           entry->save_code(buf->code_begin(), buffer.insts_size());

         }

       }

 #endif

       new_adapter = AdapterBlob::create(&buffer);

       NOT_PRODUCT(insts_size = buffer.insts_size());

     }

     if (new_adapter == NULL) {

       // CodeCache is full, disable compilation

       // Ought to log this but compile log is only per compile thread

       // and we're some non descript Java thread.

       MutexUnlocker mu(AdapterHandlerLibrary_lock);

       CompileBroker::handle_full_code_cache();

       return NULL; // Out of CodeCache space

     }

     entry->relocate(new_adapter->content_begin());

 #ifndef PRODUCT

     // debugging suppport

     if (PrintAdapterHandlers || PrintStubCode) {

       ttyLocker ttyl;

       entry->print_adapter_on(tty);

       tty->print_cr("i2c argument handler #%d for: %s %s (%d bytes generated)",

                     _adapters->number_of_entries(), (method->is_static() ? "static" : "receiver"),

                     method->signature()->as_C_string(), insts_size);

       tty->print_cr("c2i argument handler starts at %p",entry->get_c2i_entry());

       if (Verbose || PrintStubCode) {

         address first_pc = entry->base_address();

         if (first_pc != NULL) {

           Disassembler::decode(first_pc, first_pc + insts_size);

           tty->cr();

         }

       }

     }

 #endif

     // Add the entry only if the entry contains all required checks (see sharedRuntime_xxx.cpp)

     // The checks are inserted only if -XX:+VerifyAdapterCalls is specified.

     if (contains_all_checks || !VerifyAdapterCalls) {

       _adapters->add(entry);

     }

   }

   // Outside of the lock

   if (new_adapter != NULL) {

     char blob_id[256];

     jio_snprintf(blob_id,

                  sizeof(blob_id),

                  "%s(%s)@" PTR_FORMAT,

                  new_adapter->name(),

                  fingerprint->as_string(),

                  new_adapter->content_begin());

     Forte::register_stub(blob_id, new_adapter->content_begin(),new_adapter->content_end());

     if (JvmtiExport::should_post_dynamic_code_generated()) {

       JvmtiExport::post_dynamic_code_generated(blob_id, new_adapter->content_begin(), new_adapter->content_end());

     }

   }

   return entry;

 }

 address AdapterHandlerEntry::base_address() {

   address base = _i2c_entry;

   if (base == NULL)  base = _c2i_entry;

   assert(base <= _c2i_entry || _c2i_entry == NULL, "");

   assert(base <= _c2i_unverified_entry || _c2i_unverified_entry == NULL, "");

   return base;

 }

 void AdapterHandlerEntry::relocate(address new_base) {

   address old_base = base_address();

   assert(old_base != NULL, "");

   ptrdiff_t delta = new_base - old_base;

   if (_i2c_entry != NULL)

     _i2c_entry += delta;

   if (_c2i_entry != NULL)

     _c2i_entry += delta;

   if (_c2i_unverified_entry != NULL)

     _c2i_unverified_entry += delta;

   assert(base_address() == new_base, "");

 }

 void AdapterHandlerEntry::deallocate() {

   delete _fingerprint;

 #ifdef ASSERT

   if (_saved_code) FREE_C_HEAP_ARRAY(unsigned char, _saved_code, mtCode);

 #endif

 }

 #ifdef ASSERT

 // Capture the code before relocation so that it can be compared

 // against other versions.  If the code is captured after relocation

 // then relative instructions won't be equivalent.

 void AdapterHandlerEntry::save_code(unsigned char* buffer, int length) {

   _saved_code = NEW_C_HEAP_ARRAY(unsigned char, length, mtCode);

   _saved_code_length = length;

   memcpy(_saved_code, buffer, length);

 }

 bool AdapterHandlerEntry::compare_code(unsigned char* buffer, int length) {

   if (length != _saved_code_length) {

     return false;

   }

   return (memcmp(buffer, _saved_code, length) == 0) ? true : false;

 }

 #endif

 /**

  * Create a native wrapper for this native method.  The wrapper converts the

  * Java-compiled calling convention to the native convention, handles

  * arguments, and transitions to native.  On return from the native we transition

  * back to java blocking if a safepoint is in progress.

  */

 void AdapterHandlerLibrary::create_native_wrapper(methodHandle method) {

   ResourceMark rm;

   nmethod* nm = NULL;

   assert(method->is_native(), "must be native");

   assert(method->is_method_handle_intrinsic() ||

          method->has_native_function(), "must have something valid to call!");

   {

     // Perform the work while holding the lock, but perform any printing outside the lock

     MutexLocker mu(AdapterHandlerLibrary_lock);