1 /*
   2  * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 #include "precompiled.hpp"
  25 
  26 #include "aot/compiledIC_aot.hpp"
  27 #include "code/codeCache.hpp"
  28 #include "memory/resourceArea.hpp"
  29 
  30 void CompiledDirectStaticCall::set_to_far(const methodHandle& callee, address entry) {
  31   address stub = find_stub(true /* is_far */);
  32   guarantee(stub != NULL, "stub not found");
  33 
  34   if (TraceICs) {
  35     ResourceMark rm;
  36     tty->print_cr("CompiledDirectStaticCall@" INTPTR_FORMAT ": set_to_far %s",
  37                   p2i(instruction_address()),
  38                   callee->name_and_sig_as_C_string());
  39   }
  40 
  41   // Creation also verifies the object.
  42   // mov rax,imm_aot_addr
  43   // jmp rax
  44   NativeMovConstReg* destination_holder = nativeMovConstReg_at(stub);
  45 
  46 #ifdef ASSERT
  47   // read the value once
  48   intptr_t data = destination_holder->data();
  49   assert(data == 0 || data == (intptr_t)entry,
  50          "MT-unsafe modification of inline cache");
  51 #endif
  52 
  53   // Update stub.
  54   destination_holder->set_data((intptr_t)entry);
  55 
  56   // Update jump to call.
  57   set_destination_mt_safe(stub);
  58 }
  59 
  60 void CompiledPltStaticCall::set_to_interpreted(const methodHandle& callee, address entry) {
  61   address stub = find_stub();
  62   guarantee(stub != NULL, "stub not found");
  63   if (TraceICs) {
  64     ResourceMark rm;
  65     tty->print_cr("CompiledPltStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
  66                   p2i(instruction_address()),
  67                   callee->name_and_sig_as_C_string());
  68   }
  69 
  70   // Creation also verifies the object.
  71   NativeLoadGot* method_loader = nativeLoadGot_at(stub);
  72   NativeGotJump* jump          = nativeGotJump_at(method_loader->next_instruction_address());
  73 
  74   intptr_t data = method_loader->data();
  75   address destination = jump->destination();
  76   assert(data == 0 || data == (intptr_t)callee(),
  77          "a) MT-unsafe modification of inline cache");
  78   assert(destination == (address)-1 || destination == entry,
  79          "b) MT-unsafe modification of inline cache");
  80 
  81   // Update stub.
  82   method_loader->set_data((intptr_t)callee());
  83   jump->set_jump_destination(entry);
  84 
  85   // Update jump to call.
  86   set_destination_mt_safe(stub);
  87 }
  88 
  89 #ifdef NEVER_CALLED
  90 void CompiledPltStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
  91   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
  92   // Reset stub.
  93   address stub = static_stub->addr();
  94   assert(stub != NULL, "stub not found");
  95   // Creation also verifies the object.
  96   NativeLoadGot* method_loader = nativeLoadGot_at(stub);
  97   NativeGotJump* jump          = nativeGotJump_at(method_loader->next_instruction_address());
  98   method_loader->set_data(0);
  99   jump->set_jump_destination((address)-1);
 100 }
 101 #endif
 102 
 103 #ifndef PRODUCT
 104 void CompiledPltStaticCall::verify() {
 105   // Verify call.
 106   _call->verify();
 107 
 108 #ifdef ASSERT
 109   CodeBlob *cb = CodeCache::find_blob_unsafe((address) _call);
 110   assert(cb && cb->is_aot(), "CompiledPltStaticCall can only be used on AOTCompiledMethod");
 111 #endif
 112 
 113   // Verify stub.
 114   address stub = find_stub();
 115   assert(stub != NULL, "no stub found for static call");
 116   // Creation also verifies the object.
 117   NativeLoadGot*     method_loader = nativeLoadGot_at(stub);
 118   NativeGotJump*     jump          = nativeGotJump_at(method_loader->next_instruction_address());
 119   // Verify state.
 120   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
 121 }
 122 #endif // !PRODUCT