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 package jdk.tools.jaotc.binformat.elf;
  25 
  26 import java.io.IOException;
  27 import java.nio.charset.StandardCharsets;
  28 import java.util.ArrayList;
  29 import java.util.Collection;
  30 import java.util.List;
  31 import java.util.Map;
  32 
  33 import jdk.tools.jaotc.binformat.BinaryContainer;
  34 import jdk.tools.jaotc.binformat.ByteContainer;
  35 import jdk.tools.jaotc.binformat.CodeContainer;
  36 import jdk.tools.jaotc.binformat.ReadOnlyDataContainer;
  37 import jdk.tools.jaotc.binformat.Relocation;
  38 import jdk.tools.jaotc.binformat.Relocation.RelocType;
  39 import jdk.tools.jaotc.binformat.Symbol;
  40 import jdk.tools.jaotc.binformat.Symbol.Binding;
  41 import jdk.tools.jaotc.binformat.Symbol.Kind;
  42 
  43 import jdk.tools.jaotc.binformat.elf.ElfSymbol;
  44 import jdk.tools.jaotc.binformat.elf.ElfTargetInfo;
  45 import jdk.tools.jaotc.binformat.elf.Elf.Elf64_Ehdr;
  46 import jdk.tools.jaotc.binformat.elf.Elf.Elf64_Shdr;
  47 import jdk.tools.jaotc.binformat.elf.Elf.Elf64_Sym;
  48 import jdk.tools.jaotc.binformat.elf.Elf.Elf64_Rela;
  49 
  50 
  51 public class AMD64JELFRelocObject extends JELFRelocObject {
  52 
  53     AMD64JELFRelocObject(BinaryContainer binContainer, String outputFileName) {
  54         super(binContainer, outputFileName);
  55     }
  56 
  57     protected void createRelocation(Symbol symbol, Relocation reloc, ElfRelocTable elfRelocTable) {
  58         RelocType relocType = reloc.getType();
  59 
  60         int elfRelocType = getELFRelocationType(relocType);
  61         ElfSymbol sym = (ElfSymbol) symbol.getNativeSymbol();
  62         int symno = sym.getIndex();
  63         int sectindex = reloc.getSection().getSectionId();
  64         int offset = reloc.getOffset();
  65         int addend = 0;
  66 
  67         switch (relocType) {
  68         case JAVA_CALL_DIRECT:
  69         case STUB_CALL_DIRECT:
  70         case FOREIGN_CALL_INDIRECT_GOT: {
  71             // Create relocation entry
  72             addend = -4; // Size in bytes of the patch location
  73             // Relocation should be applied at the location after call operand
  74             offset = offset + reloc.getSize() + addend;
  75             break;
  76         }
  77         case JAVA_CALL_INDIRECT:
  78         case METASPACE_GOT_REFERENCE:
  79         case EXTERNAL_PLT_TO_GOT: {
  80             addend = -4; // Size of 32-bit address of the GOT
  81             /*
  82              * Relocation should be applied before the test instruction to the move instruction.
  83              * reloc.getOffset() points to the test instruction after the instruction that loads the address of
  84              * polling page. So set the offset appropriately.
  85              */
  86             offset = offset + addend;
  87             break;
  88         }
  89         case EXTERNAL_GOT_TO_PLT: {
  90             // this is load time relocations
  91             break;
  92         }
  93         default:
  94             throw new InternalError("Unhandled relocation type: " + relocType);
  95         }
  96         elfRelocTable.createRelocationEntry(sectindex, offset, symno, elfRelocType, addend);
  97     }
  98 
  99     private int getELFRelocationType(RelocType relocType) {
 100         int elfRelocType = 0; // R_<ARCH>_NONE if #define'd to 0 for all values of ARCH
 101         switch (ElfTargetInfo.getElfArch()) {
 102         case Elf64_Ehdr.EM_X86_64:
 103             // Return R_X86_64_* entries based on relocType
 104             if (relocType == RelocType.JAVA_CALL_DIRECT ||
 105                 relocType == RelocType.FOREIGN_CALL_INDIRECT_GOT) {
 106                 elfRelocType = Elf64_Rela.R_X86_64_PLT32;
 107             } else if (relocType == RelocType.STUB_CALL_DIRECT) {
 108                 elfRelocType = Elf64_Rela.R_X86_64_PC32;
 109             } else if (relocType == RelocType.JAVA_CALL_INDIRECT) {
 110                 elfRelocType = Elf64_Rela.R_X86_64_NONE;
 111             } else if (relocType == RelocType.METASPACE_GOT_REFERENCE ||
 112                        relocType == RelocType.EXTERNAL_PLT_TO_GOT) {
 113                 elfRelocType = Elf64_Rela.R_X86_64_PC32;
 114             } else if (relocType == RelocType.EXTERNAL_GOT_TO_PLT) {
 115                 elfRelocType = Elf64_Rela.R_X86_64_64;
 116             } else {
 117                 assert false : "Unhandled relocation type: " + relocType;
 118             }
 119             break;
 120 
 121         default:
 122             System.out.println("Relocation Type mapping: Unhandled architecture: "
 123                                + ElfTargetInfo.getElfArch());
 124         }
 125         return elfRelocType;
 126     }
 127 }