1 //===-------------- ELF.cpp - JIT linker function for ELF -------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // ELF jit-link function.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "llvm/ExecutionEngine/JITLink/ELF.h"
14
15 #include "llvm/BinaryFormat/ELF.h"
16 #include "llvm/ExecutionEngine/JITLink/ELF_aarch64.h"
17 #include "llvm/ExecutionEngine/JITLink/ELF_i386.h"
18 #include "llvm/ExecutionEngine/JITLink/ELF_loongarch.h"
19 #include "llvm/ExecutionEngine/JITLink/ELF_riscv.h"
20 #include "llvm/ExecutionEngine/JITLink/ELF_x86_64.h"
21 #include "llvm/Object/ELF.h"
22 #include "llvm/Support/Endian.h"
23 #include "llvm/Support/Format.h"
24 #include "llvm/Support/MemoryBuffer.h"
25 #include <cstring>
26
27 using namespace llvm;
28
29 #define DEBUG_TYPE "jitlink"
30
31 namespace llvm {
32 namespace jitlink {
33
readTargetMachineArch(StringRef Buffer)34 Expected<uint16_t> readTargetMachineArch(StringRef Buffer) {
35 const char *Data = Buffer.data();
36
37 if (Data[ELF::EI_DATA] == ELF::ELFDATA2LSB) {
38 if (Data[ELF::EI_CLASS] == ELF::ELFCLASS64) {
39 if (auto File = llvm::object::ELF64LEFile::create(Buffer)) {
40 return File->getHeader().e_machine;
41 } else {
42 return File.takeError();
43 }
44 } else if (Data[ELF::EI_CLASS] == ELF::ELFCLASS32) {
45 if (auto File = llvm::object::ELF32LEFile::create(Buffer)) {
46 return File->getHeader().e_machine;
47 } else {
48 return File.takeError();
49 }
50 }
51 }
52
53 return ELF::EM_NONE;
54 }
55
56 Expected<std::unique_ptr<LinkGraph>>
createLinkGraphFromELFObject(MemoryBufferRef ObjectBuffer)57 createLinkGraphFromELFObject(MemoryBufferRef ObjectBuffer) {
58 StringRef Buffer = ObjectBuffer.getBuffer();
59 if (Buffer.size() < ELF::EI_MAG3 + 1)
60 return make_error<JITLinkError>("Truncated ELF buffer");
61
62 if (memcmp(Buffer.data(), ELF::ElfMagic, strlen(ELF::ElfMagic)) != 0)
63 return make_error<JITLinkError>("ELF magic not valid");
64
65 Expected<uint16_t> TargetMachineArch = readTargetMachineArch(Buffer);
66 if (!TargetMachineArch)
67 return TargetMachineArch.takeError();
68
69 switch (*TargetMachineArch) {
70 case ELF::EM_AARCH64:
71 return createLinkGraphFromELFObject_aarch64(ObjectBuffer);
72 case ELF::EM_LOONGARCH:
73 return createLinkGraphFromELFObject_loongarch(ObjectBuffer);
74 case ELF::EM_RISCV:
75 return createLinkGraphFromELFObject_riscv(ObjectBuffer);
76 case ELF::EM_X86_64:
77 return createLinkGraphFromELFObject_x86_64(ObjectBuffer);
78 case ELF::EM_386:
79 return createLinkGraphFromELFObject_i386(ObjectBuffer);
80 default:
81 return make_error<JITLinkError>(
82 "Unsupported target machine architecture in ELF object " +
83 ObjectBuffer.getBufferIdentifier());
84 }
85 }
86
link_ELF(std::unique_ptr<LinkGraph> G,std::unique_ptr<JITLinkContext> Ctx)87 void link_ELF(std::unique_ptr<LinkGraph> G,
88 std::unique_ptr<JITLinkContext> Ctx) {
89 switch (G->getTargetTriple().getArch()) {
90 case Triple::aarch64:
91 link_ELF_aarch64(std::move(G), std::move(Ctx));
92 return;
93 case Triple::loongarch32:
94 case Triple::loongarch64:
95 link_ELF_loongarch(std::move(G), std::move(Ctx));
96 return;
97 case Triple::riscv32:
98 case Triple::riscv64:
99 link_ELF_riscv(std::move(G), std::move(Ctx));
100 return;
101 case Triple::x86_64:
102 link_ELF_x86_64(std::move(G), std::move(Ctx));
103 return;
104 case Triple::x86:
105 link_ELF_i386(std::move(G), std::move(Ctx));
106 return;
107 default:
108 Ctx->notifyFailed(make_error<JITLinkError>(
109 "Unsupported target machine architecture in ELF link graph " +
110 G->getName()));
111 return;
112 }
113 }
114
115 } // end namespace jitlink
116 } // end namespace llvm
117