1 //===-- RelocVisitor.h - Visitor for object file relocations -*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file provides a wrapper around all the different types of relocations
11 // in different file formats, such that a client can handle them in a unified
12 // manner by only implementing a minimal number of functions.
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_OBJECT_RELOCVISITOR_H
17 #define LLVM_OBJECT_RELOCVISITOR_H
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/Object/ObjectFile.h"
21 #include "llvm/Support/Debug.h"
22 #include "llvm/Support/ELF.h"
23 #include "llvm/Support/raw_ostream.h"
29 // The computed value after applying the relevant relocations.
32 // The width of the value; how many bytes to touch when applying the
35 RelocToApply(const RelocToApply &In) : Value(In.Value), Width(In.Width) {}
36 RelocToApply(int64_t Value, char Width) : Value(Value), Width(Width) {}
37 RelocToApply() : Value(0), Width(0) {}
40 /// @brief Base class for object file relocation visitors.
43 explicit RelocVisitor(StringRef FileFormat)
44 : FileFormat(FileFormat), HasError(false) {}
46 // TODO: Should handle multiple applied relocations via either passing in the
47 // previously computed value or just count paired relocations as a single
49 RelocToApply visit(uint32_t RelocType, RelocationRef R, uint64_t SecAddr = 0,
51 if (FileFormat == "ELF64-x86-64") {
53 case llvm::ELF::R_X86_64_NONE:
54 return visitELF_X86_64_NONE(R);
55 case llvm::ELF::R_X86_64_64:
56 return visitELF_X86_64_64(R, Value);
57 case llvm::ELF::R_X86_64_PC32:
58 return visitELF_X86_64_PC32(R, Value, SecAddr);
59 case llvm::ELF::R_X86_64_32:
60 return visitELF_X86_64_32(R, Value);
61 case llvm::ELF::R_X86_64_32S:
62 return visitELF_X86_64_32S(R, Value);
65 return RelocToApply();
67 } else if (FileFormat == "ELF32-i386") {
69 case llvm::ELF::R_386_NONE:
70 return visitELF_386_NONE(R);
71 case llvm::ELF::R_386_32:
72 return visitELF_386_32(R, Value);
73 case llvm::ELF::R_386_PC32:
74 return visitELF_386_PC32(R, Value, SecAddr);
77 return RelocToApply();
79 } else if (FileFormat == "ELF64-ppc64") {
81 case llvm::ELF::R_PPC64_ADDR32:
82 return visitELF_PPC64_ADDR32(R, Value);
85 return RelocToApply();
87 } else if (FileFormat == "ELF32-mips") {
89 case llvm::ELF::R_MIPS_32:
90 return visitELF_MIPS_32(R, Value);
93 return RelocToApply();
95 } else if (FileFormat == "ELF64-aarch64") {
97 case llvm::ELF::R_AARCH64_ABS32:
98 return visitELF_AARCH64_ABS32(R, Value);
99 case llvm::ELF::R_AARCH64_ABS64:
100 return visitELF_AARCH64_ABS64(R, Value);
103 return RelocToApply();
105 } else if (FileFormat == "ELF64-s390") {
107 case llvm::ELF::R_390_32:
108 return visitELF_390_32(R, Value);
109 case llvm::ELF::R_390_64:
110 return visitELF_390_64(R, Value);
113 return RelocToApply();
117 return RelocToApply();
120 bool error() { return HasError; }
123 StringRef FileFormat;
129 RelocToApply visitELF_386_NONE(RelocationRef R) {
130 return RelocToApply(0, 0);
133 // Ideally the Addend here will be the addend in the data for
134 // the relocation. It's not actually the case for Rel relocations.
135 RelocToApply visitELF_386_32(RelocationRef R, uint64_t Value) {
137 R.getAdditionalInfo(Addend);
138 return RelocToApply(Value + Addend, 4);
141 RelocToApply visitELF_386_PC32(RelocationRef R, uint64_t Value,
144 R.getAdditionalInfo(Addend);
146 R.getOffset(Address);
147 return RelocToApply(Value + Addend - Address, 4);
151 RelocToApply visitELF_X86_64_NONE(RelocationRef R) {
152 return RelocToApply(0, 0);
154 RelocToApply visitELF_X86_64_64(RelocationRef R, uint64_t Value) {
156 R.getAdditionalInfo(Addend);
157 return RelocToApply(Value + Addend, 8);
159 RelocToApply visitELF_X86_64_PC32(RelocationRef R, uint64_t Value,
162 R.getAdditionalInfo(Addend);
164 R.getOffset(Address);
165 return RelocToApply(Value + Addend - Address, 4);
167 RelocToApply visitELF_X86_64_32(RelocationRef R, uint64_t Value) {
169 R.getAdditionalInfo(Addend);
170 uint32_t Res = (Value + Addend) & 0xFFFFFFFF;
171 return RelocToApply(Res, 4);
173 RelocToApply visitELF_X86_64_32S(RelocationRef R, uint64_t Value) {
175 R.getAdditionalInfo(Addend);
176 int32_t Res = (Value + Addend) & 0xFFFFFFFF;
177 return RelocToApply(Res, 4);
181 RelocToApply visitELF_PPC64_ADDR32(RelocationRef R, uint64_t Value) {
183 R.getAdditionalInfo(Addend);
184 uint32_t Res = (Value + Addend) & 0xFFFFFFFF;
185 return RelocToApply(Res, 4);
189 RelocToApply visitELF_MIPS_32(RelocationRef R, uint64_t Value) {
191 R.getAdditionalInfo(Addend);
192 uint32_t Res = (Value + Addend) & 0xFFFFFFFF;
193 return RelocToApply(Res, 4);
197 RelocToApply visitELF_AARCH64_ABS32(RelocationRef R, uint64_t Value) {
199 R.getAdditionalInfo(Addend);
200 int64_t Res = Value + Addend;
202 // Overflow check allows for both signed and unsigned interpretation.
203 if (Res < INT32_MIN || Res > UINT32_MAX)
206 return RelocToApply(static_cast<uint32_t>(Res), 4);
209 RelocToApply visitELF_AARCH64_ABS64(RelocationRef R, uint64_t Value) {
211 R.getAdditionalInfo(Addend);
212 return RelocToApply(Value + Addend, 8);
216 RelocToApply visitELF_390_32(RelocationRef R, uint64_t Value) {
218 R.getAdditionalInfo(Addend);
219 int64_t Res = Value + Addend;
221 // Overflow check allows for both signed and unsigned interpretation.
222 if (Res < INT32_MIN || Res > UINT32_MAX)
225 return RelocToApply(static_cast<uint32_t>(Res), 4);
228 RelocToApply visitELF_390_64(RelocationRef R, uint64_t Value) {
230 R.getAdditionalInfo(Addend);
231 return RelocToApply(Value + Addend, 8);