xref: /llvm-project/llvm/lib/ExecutionEngine/JITLink/MachO.cpp (revision 88816bdd2f1ad148f18dad77884073fb350680f3)
1 //===-------------- MachO.cpp - JIT linker function for MachO -------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // MachO jit-link function.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/ExecutionEngine/JITLink/MachO.h"
15 
16 #include "llvm/BinaryFormat/MachO.h"
17 #include "llvm/ExecutionEngine/JITLink/MachO_x86_64.h"
18 #include "llvm/Support/Endian.h"
19 #include "llvm/Support/Format.h"
20 #include "llvm/Support/MemoryBuffer.h"
21 
22 using namespace llvm;
23 
24 #define DEBUG_TYPE "jitlink"
25 
26 namespace llvm {
27 namespace jitlink {
28 
29 void jitLink_MachO(std::unique_ptr<JITLinkContext> Ctx) {
30 
31   // We don't want to do full MachO validation here. Just parse enough of the
32   // header to find out what MachO linker to use.
33 
34   StringRef Data = Ctx->getObjectBuffer().getBuffer();
35   if (Data.size() < 4) {
36     Ctx->notifyFailed(make_error<JITLinkError>("Truncated MachO buffer"));
37     return;
38   }
39 
40   uint32_t Magic;
41   memcpy(&Magic, Data.data(), sizeof(uint32_t));
42   LLVM_DEBUG({
43     dbgs() << "jitLink_MachO: magic = " << format("0x%08" PRIx32, Magic)
44            << ", identifier = \""
45            << Ctx->getObjectBuffer().getBufferIdentifier() << "\"\n";
46   });
47 
48   if (Magic == MachO::MH_MAGIC || Magic == MachO::MH_CIGAM) {
49     Ctx->notifyFailed(
50         make_error<JITLinkError>("MachO 32-bit platforms not supported"));
51     return;
52   } else if (Magic == MachO::MH_MAGIC_64 || Magic == MachO::MH_CIGAM_64) {
53     MachO::mach_header_64 Header;
54 
55     memcpy(&Header, Data.data(), sizeof(MachO::mach_header_64));
56     if (Magic == MachO::MH_CIGAM_64)
57       swapStruct(Header);
58 
59     LLVM_DEBUG({
60       dbgs() << "jitLink_MachO: cputype = "
61              << format("0x%08" PRIx32, Header.cputype)
62              << ", cpusubtype = " << format("0x%08" PRIx32, Header.cpusubtype)
63              << "\n";
64     });
65 
66     switch (Header.cputype) {
67     case MachO::CPU_TYPE_X86_64:
68       return jitLink_MachO_x86_64(std::move(Ctx));
69     }
70     Ctx->notifyFailed(make_error<JITLinkError>("MachO-64 CPU type not valid"));
71     return;
72   }
73 
74   Ctx->notifyFailed(make_error<JITLinkError>("MachO magic not valid"));
75 }
76 
77 } // end namespace jitlink
78 } // end namespace llvm
79