1 /*
   2  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "asm/macroAssembler.inline.hpp"
  28 #include "code/compiledIC.hpp"
  29 #include "code/icBuffer.hpp"
  30 #include "code/nmethod.hpp"
  31 #include "memory/resourceArea.hpp"
  32 #include "runtime/mutexLocker.hpp"
  33 #include "runtime/safepoint.hpp"
  34 
  35 // Release the CompiledICHolder* associated with this call site is there is one.
  36 void CompiledIC::cleanup_call_site(virtual_call_Relocation* call_site) {
  37   // This call site might have become stale so inspect it carefully.
  38   NativeCall* call = nativeCall_at(call_site->addr());
  39   if (is_icholder_entry(call->destination())) {
  40     NativeMovConstReg* value = nativeMovConstReg_at(call_site->cached_value());
  41     InlineCacheBuffer::queue_for_release((CompiledICHolder*)value->data());
  42   }
  43 }
  44 
  45 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site) {
  46   // This call site might have become stale so inspect it carefully.
  47   NativeCall* call = nativeCall_at(call_site->addr());
  48   return is_icholder_entry(call->destination());
  49 }
  50 
  51 // ----------------------------------------------------------------------------
  52 
  53 #define __ _masm.
  54 address CompiledStaticCall::emit_to_interp_stub(CodeBuffer &cbuf, address mark) {
  55   // Stub is fixed up when the corresponding call is converted from
  56   // calling compiled code to calling interpreted code.
  57   // mov rmethod, 0
  58   // jmp -4 # to self
  59 
  60   if (mark == NULL) {
  61     mark = cbuf.insts_mark();  // Get mark within main instrs section.
  62   }
  63 
  64   // Note that the code buffer's insts_mark is always relative to insts.
  65   // That's why we must use the macroassembler to generate a stub.
  66   MacroAssembler _masm(&cbuf);
  67 
  68   address base = __ start_a_stub(to_interp_stub_size());
  69   int offset = __ offset();
  70   if (base == NULL) {
  71     return NULL;  // CodeBuffer::expand failed
  72   }
  73   // static stub relocation stores the instruction address of the call
  74   __ relocate(static_stub_Relocation::spec(mark));
  75   // static stub relocation also tags the Method* in the code-stream.
  76   __ mov_metadata(rmethod, (Metadata*)NULL);
  77   __ movptr(rscratch1, 0);
  78   __ br(rscratch1);
  79 
  80   assert((__ offset() - offset) <= (int)to_interp_stub_size(), "stub too big");
  81   __ end_a_stub();
  82   return base;
  83 }
  84 #undef __
  85 
  86 int CompiledStaticCall::to_interp_stub_size() {
  87   return 7 * NativeInstruction::instruction_size;
  88 }
  89 
  90 // Relocation entries for call stub, compiled java to interpreter.
  91 int CompiledStaticCall::reloc_to_interp_stub() {
  92   return 4; // 3 in emit_to_interp_stub + 1 in emit_call
  93 }
  94 
  95 void CompiledStaticCall::set_to_interpreted(methodHandle callee, address entry) {
  96   address stub = find_stub();
  97   guarantee(stub != NULL, "stub not found");
  98 
  99   if (TraceICs) {
 100     ResourceMark rm;
 101     tty->print_cr("CompiledStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
 102                   p2i(instruction_address()),
 103                   callee->name_and_sig_as_C_string());
 104   }
 105 
 106   // Creation also verifies the object.
 107   NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
 108 #ifndef PRODUCT
 109   NativeGeneralJump* jump = nativeGeneralJump_at(method_holder->next_instruction_address());
 110 
 111   assert(method_holder->data() == 0 || method_holder->data() == (intptr_t)callee(),
 112          "a) MT-unsafe modification of inline cache");
 113   assert(method_holder->data() == 0 || jump->jump_destination() == entry,
 114          "b) MT-unsafe modification of inline cache");
 115 #endif
 116   // Update stub.
 117   method_holder->set_data((intptr_t)callee());
 118   NativeGeneralJump::insert_unconditional(method_holder->next_instruction_address(), entry);
 119   ICache::invalidate_range(stub, to_interp_stub_size());
 120   // Update jump to call.
 121   set_destination_mt_safe(stub);
 122 }
 123 
 124 void CompiledStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
 125   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
 126   // Reset stub.
 127   address stub = static_stub->addr();
 128   assert(stub != NULL, "stub not found");
 129   // Creation also verifies the object.
 130   NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
 131   method_holder->set_data(0);
 132 }
 133 
 134 //-----------------------------------------------------------------------------
 135 // Non-product mode code
 136 #ifndef PRODUCT
 137 
 138 void CompiledStaticCall::verify() {
 139   // Verify call.
 140   NativeCall::verify();
 141   if (os::is_MP()) {
 142     verify_alignment();
 143   }
 144 
 145   // Verify stub.
 146   address stub = find_stub();
 147   assert(stub != NULL, "no stub found for static call");
 148   // Creation also verifies the object.
 149   NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
 150   NativeJump*        jump          = nativeJump_at(method_holder->next_instruction_address());
 151 
 152   // Verify state.
 153   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
 154 }
 155 
 156 #endif // !PRODUCT
--- EOF ---