1 /*
   2  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2016 SAP SE. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "asm/macroAssembler.inline.hpp"
  28 #include "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 #ifdef COMPILER2
  35 #include "opto/matcher.hpp"
  36 #endif
  37 
  38 // ----------------------------------------------------------------------------
  39 
  40 #undef  __
  41 #define __ _masm.
  42 
  43 address CompiledStaticCall::emit_to_interp_stub(CodeBuffer &cbuf, address mark/* = NULL*/) {
  44 #ifdef COMPILER2
  45   // Stub is fixed up when the corresponding call is converted from calling
  46   // compiled code to calling interpreted code.
  47   if (mark == NULL) {
  48     // Get the mark within main instrs section which is set to the address of the call.
  49     mark = cbuf.insts_mark();
  50   }
  51   assert(mark != NULL, "mark must not be NULL");
  52 
  53   // Note that the code buffer's insts_mark is always relative to insts.
  54   // That's why we must use the macroassembler to generate a stub.
  55   MacroAssembler _masm(&cbuf);
  56 
  57   address stub = __ start_a_stub(Compile::MAX_stubs_size);
  58   if (stub == NULL) {
  59     return NULL;  // CodeBuffer::expand failed.
  60   }
  61   __ relocate(static_stub_Relocation::spec(mark));
  62 
  63   AddressLiteral meta = __ allocate_metadata_address(NULL);
  64   bool success = __ load_const_from_toc(as_Register(Matcher::inline_cache_reg_encode()), meta);
  65 
  66   __ set_inst_mark();
  67   AddressLiteral a((address)-1);
  68   success = success && __ load_const_from_toc(Z_R1, a);
  69   if (!success) {
  70     return NULL;  // CodeCache is full.
  71   }
  72 
  73   __ z_br(Z_R1);
  74   __ end_a_stub(); // Update current stubs pointer and restore insts_end.
  75   return stub;
  76 #else
  77   ShouldNotReachHere();
  78 #endif
  79 }
  80 
  81 #undef __
  82 
  83 int CompiledStaticCall::to_interp_stub_size() {
  84   return 2 * MacroAssembler::load_const_from_toc_size() +
  85          2; // branch
  86 }
  87 
  88 // Relocation entries for call stub, compiled java to interpreter.
  89 int CompiledStaticCall::reloc_to_interp_stub() {
  90   return 5; // 4 in emit_java_to_interp + 1 in Java_Static_Call
  91 }
  92 
  93 void CompiledDirectStaticCall::set_to_interpreted(const methodHandle& callee, address entry) {
  94   address stub = find_stub(/*is_aot*/ false);
  95   guarantee(stub != NULL, "stub not found");
  96 
  97   if (TraceICs) {
  98     ResourceMark rm;
  99     tty->print_cr("CompiledDirectStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
 100                   p2i(instruction_address()),
 101                   callee->name_and_sig_as_C_string());
 102   }
 103 
 104   // Creation also verifies the object.
 105   NativeMovConstReg* method_holder = nativeMovConstReg_at(stub + NativeCall::get_IC_pos_in_java_to_interp_stub());
 106   NativeJump*        jump          = nativeJump_at(method_holder->next_instruction_address());
 107 
 108 #ifdef ASSERT
 109   // A generated lambda form might be deleted from the Lambdaform
 110   // cache in MethodTypeForm.  If a jit compiled lambdaform method
 111   // becomes not entrant and the cache access returns null, the new
 112   // resolve will lead to a new generated LambdaForm.
 113   volatile intptr_t data = method_holder->data();
 114   volatile address destination = jump->jump_destination();
 115   assert(data == 0 || data == (intptr_t)callee() || callee->is_compiled_lambda_form(),
 116          "a) MT-unsafe modification of inline cache");
 117   assert(destination == (address)-1 || destination == entry,
 118          "b) MT-unsafe modification of inline cache");
 119 #endif
 120 
 121   // Update stub.
 122   method_holder->set_data((intptr_t)callee());
 123   jump->set_jump_destination(entry);
 124 
 125   // Update jump to call.
 126   set_destination_mt_safe(stub);
 127 }
 128 
 129 void CompiledDirectStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
 130   // Reset stub.
 131   address stub = static_stub->addr();
 132   assert(stub != NULL, "stub not found");
 133   assert(CompiledICLocker::is_safe(stub), "mt unsafe call");
 134   // Creation also verifies the object.
 135   NativeMovConstReg* method_holder = nativeMovConstReg_at(stub + NativeCall::get_IC_pos_in_java_to_interp_stub());
 136   NativeJump*        jump          = nativeJump_at(method_holder->next_instruction_address());
 137   method_holder->set_data(0);
 138   jump->set_jump_destination((address)-1);
 139 }
 140 
 141 //-----------------------------------------------------------------------------
 142 
 143 #ifndef PRODUCT
 144 
 145 void CompiledDirectStaticCall::verify() {
 146   // Verify call.
 147   _call->verify();
 148   _call->verify_alignment();
 149 
 150   // Verify stub.
 151   address stub = find_stub(/*is_aot*/ false);
 152   assert(stub != NULL, "no stub found for static call");
 153   // Creation also verifies the object.
 154   NativeMovConstReg* method_holder = nativeMovConstReg_at(stub + NativeCall::get_IC_pos_in_java_to_interp_stub());
 155   NativeJump*        jump          = nativeJump_at(method_holder->next_instruction_address());
 156 
 157   // Verify state.
 158   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
 159 }
 160 
 161 #endif // !PRODUCT