1 /*
   2  * Copyright (c) 2016, 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 "aot/compiledIC_aot.hpp"
  25 #include "code/codeCache.hpp"
  26 #include "memory/resourceArea.hpp"
  27 
  28 void CompiledDirectStaticCall::set_to_far(const methodHandle& callee, address entry) {
  29   address stub = find_stub(true /* is_far */);
  30   guarantee(stub != NULL, "stub not found");
  31 
  32   if (TraceICs) {
  33     ResourceMark rm;
  34     tty->print_cr("CompiledDirectStaticCall@" INTPTR_FORMAT ": set_to_far %s",
  35                   p2i(instruction_address()),
  36                   callee->name_and_sig_as_C_string());
  37   }
  38 
  39   // Creation also verifies the object.
  40   // mov rax,imm_aot_addr
  41   // jmp rax
  42   NativeMovConstReg* destination_holder = nativeMovConstReg_at(stub);
  43 
  44 #ifdef ASSERT
  45   // read the value once
  46   intptr_t data = destination_holder->data();
  47   assert(data == 0 || data == (intptr_t)entry,
  48          "MT-unsafe modification of inline cache");
  49 #endif
  50 
  51   // Update stub.
  52   destination_holder->set_data((intptr_t)entry);
  53 
  54   // Update jump to call.
  55   set_destination_mt_safe(stub);
  56 }
  57 
  58 void CompiledPltStaticCall::set_to_interpreted(const methodHandle& callee, address entry) {
  59   address stub = find_stub();
  60   guarantee(stub != NULL, "stub not found");
  61   if (TraceICs) {
  62     ResourceMark rm;
  63     tty->print_cr("CompiledPltStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
  64                   p2i(instruction_address()),
  65                   callee->name_and_sig_as_C_string());
  66   }
  67 
  68   // Creation also verifies the object.
  69   NativeLoadGot* method_loader = nativeLoadGot_at(stub);
  70   NativeGotJump* jump          = nativeGotJump_at(method_loader->next_instruction_address());
  71 
  72   intptr_t data = method_loader->data();
  73   address destination = jump->destination();
  74   assert(data == 0 || data == (intptr_t)callee(),
  75          "a) MT-unsafe modification of inline cache");
  76   assert(destination == (address)-1 || destination == entry,
  77          "b) MT-unsafe modification of inline cache");
  78 
  79   // Update stub.
  80   method_loader->set_data((intptr_t)callee());
  81   jump->set_jump_destination(entry);
  82 
  83   // Update jump to call.
  84   set_destination_mt_safe(stub);
  85 }
  86 
  87 #ifdef NEVER_CALLED
  88 void CompiledPltStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
  89   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
  90   // Reset stub.
  91   address stub = static_stub->addr();
  92   assert(stub != NULL, "stub not found");
  93   // Creation also verifies the object.
  94   NativeLoadGot* method_loader = nativeLoadGot_at(stub);
  95   NativeGotJump* jump          = nativeGotJump_at(method_loader->next_instruction_address());
  96   method_loader->set_data(0);
  97   jump->set_jump_destination((address)-1);
  98 }
  99 #endif
 100 
 101 #ifndef PRODUCT
 102 void CompiledPltStaticCall::verify() {
 103   // Verify call.
 104   _call->verify();
 105 
 106 #ifdef ASSERT
 107   CodeBlob *cb = CodeCache::find_blob_unsafe((address) _call);
 108   assert(cb && cb->is_aot(), "CompiledPltStaticCall can only be used on AOTCompiledMethod");
 109 #endif
 110 
 111   // Verify stub.
 112   address stub = find_stub();
 113   assert(stub != NULL, "no stub found for static call");
 114   // Creation also verifies the object.
 115   NativeLoadGot*     method_loader = nativeLoadGot_at(stub);
 116   NativeGotJump*     jump          = nativeGotJump_at(method_loader->next_instruction_address());
 117   // Verify state.
 118   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
 119 }
 120 #endif // !PRODUCT