1 /*
   2  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2018, 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 "gc/shared/barrierSetAssembler.hpp"
  29 #include "interpreter/interp_masm.hpp"
  30 
  31 #define __ masm->
  32 
  33 void BarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
  34                                    Register base, RegisterOrConstant ind_or_offs, Register val,
  35                                    Register tmp1, Register tmp2, Register tmp3, bool needs_frame) {
  36   bool on_heap  = (decorators & IN_HEAP) != 0;
  37   bool in_native = (decorators & IN_NATIVE) != 0;
  38   bool not_null = (decorators & OOP_NOT_NULL) != 0;
  39   assert(on_heap || in_native, "where?");
  40   assert_different_registers(base, val, tmp1, tmp2, R0);
  41 
  42   switch (type) {
  43   case T_ARRAY:
  44   case T_OBJECT: {
  45     if (UseCompressedOops && on_heap) {
  46       Register co = tmp1;
  47       if (val == noreg) {
  48         __ li(co, 0);
  49       } else {
  50         co = not_null ? __ encode_heap_oop_not_null(tmp1, val) : __ encode_heap_oop(tmp1, val);
  51       }
  52       __ stw(co, ind_or_offs, base, tmp2);
  53     } else {
  54       if (val == noreg) {
  55         val = tmp1;
  56         __ li(val, 0);
  57       }
  58       __ std(val, ind_or_offs, base, tmp2);
  59     }
  60     break;
  61   }
  62   default: Unimplemented();
  63   }
  64 }
  65 
  66 void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
  67                                   Register base, RegisterOrConstant ind_or_offs, Register dst,
  68                                   Register tmp1, Register tmp2, bool needs_frame, Label *L_handle_null) {
  69   bool on_heap  = (decorators & IN_HEAP) != 0;
  70   bool in_native = (decorators & IN_NATIVE) != 0;
  71   bool not_null = (decorators & OOP_NOT_NULL) != 0;
  72   assert(on_heap || in_native, "where?");
  73   assert_different_registers(ind_or_offs.register_or_noreg(), dst, R0);
  74 
  75   switch (type) {
  76   case T_ARRAY:
  77   case T_OBJECT: {
  78     if (UseCompressedOops && on_heap) {
  79       if (L_handle_null != NULL) { // Label provided.
  80         __ lwz(dst, ind_or_offs, base);
  81         __ cmpwi(CCR0, dst, 0);
  82         __ beq(CCR0, *L_handle_null);
  83         __ decode_heap_oop_not_null(dst);
  84       } else if (not_null) { // Guaranteed to be not null.
  85         Register narrowOop = (tmp1 != noreg && Universe::narrow_oop_base_disjoint()) ? tmp1 : dst;
  86         __ lwz(narrowOop, ind_or_offs, base);
  87         __ decode_heap_oop_not_null(dst, narrowOop);
  88       } else { // Any oop.
  89         __ lwz(dst, ind_or_offs, base);
  90         __ decode_heap_oop(dst);
  91       }
  92     } else {
  93       __ ld(dst, ind_or_offs, base);
  94       if (L_handle_null != NULL) {
  95         __ cmpdi(CCR0, dst, 0);
  96         __ beq(CCR0, *L_handle_null);
  97       }
  98     }
  99     break;
 100   }
 101   default: Unimplemented();
 102   }
 103 }
 104 
 105 void BarrierSetAssembler::resolve_jobject(MacroAssembler* masm, Register value,
 106                                           Register tmp1, Register tmp2, bool needs_frame) {
 107   Label done;
 108   __ cmpdi(CCR0, value, 0);
 109   __ beq(CCR0, done);         // Use NULL as-is.
 110 
 111   __ clrrdi(tmp1, value, JNIHandles::weak_tag_size);
 112   __ ld(value, 0, tmp1);      // Resolve (untagged) jobject.
 113 
 114   __ verify_oop(value);
 115   __ bind(done);
 116 }