lib/ExecutionEngine/JITLink/MachO.cpp

   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_arm64.h"
  18 #include "llvm/ExecutionEngine/JITLink/MachO_x86_64.h"
  19 #include "llvm/Support/Endian.h"
  20 #include "llvm/Support/Format.h"
  21 #include "llvm/Support/MemoryBuffer.h"
  22
  23 using namespace llvm;
  24
  25 #define DEBUG_TYPE "jitlink"
  26
  27 namespace llvm {
  28 namespace jitlink {
  29
  30 void jitLink_MachO(std::unique_ptr<JITLinkContext> Ctx) {
  31
  32   // We don't want to do full MachO validation here. Just parse enough of the
  33   // header to find out what MachO linker to use.
  34
  35   StringRef Data = Ctx->getObjectBuffer().getBuffer();
  36   if (Data.size() < 4) {
  37     Ctx->notifyFailed(make_error<JITLinkError>("Truncated MachO buffer"));
  38     return;
  39   }
  40
  41   uint32_t Magic;
  42   memcpy(&Magic, Data.data(), sizeof(uint32_t));
  43   LLVM_DEBUG({
  44     dbgs() << "jitLink_MachO: magic = " << format("0x%08" PRIx32, Magic)
  45            << ", identifier = \""
  46            << Ctx->getObjectBuffer().getBufferIdentifier() << "\"\n";
  47   });
  48
  49   if (Magic == MachO::MH_MAGIC || Magic == MachO::MH_CIGAM) {
  50     Ctx->notifyFailed(
  51         make_error<JITLinkError>("MachO 32-bit platforms not supported"));
  52     return;
  53   } else if (Magic == MachO::MH_MAGIC_64 || Magic == MachO::MH_CIGAM_64) {
  54     MachO::mach_header_64 Header;
  55
  56     memcpy(&Header, Data.data(), sizeof(MachO::mach_header_64));
  57     if (Magic == MachO::MH_CIGAM_64)
  58       swapStruct(Header);
  59
  60     LLVM_DEBUG({
  61       dbgs() << "jitLink_MachO: cputype = "
  62              << format("0x%08" PRIx32, Header.cputype)
  63              << ", cpusubtype = " << format("0x%08" PRIx32, Header.cpusubtype)
  64              << "\n";
  65     });
  66
  67     switch (Header.cputype) {
  68     case MachO::CPU_TYPE_ARM64:
  69       return jitLink_MachO_arm64(std::move(Ctx));
  70     case MachO::CPU_TYPE_X86_64:
  71       return jitLink_MachO_x86_64(std::move(Ctx));
  72     }
  73     Ctx->notifyFailed(make_error<JITLinkError>("MachO-64 CPU type not valid"));
  74     return;
  75   }
  76
  77   Ctx->notifyFailed(make_error<JITLinkError>("MachO magic not valid"));
  78 }
  79
  80 } // end namespace jitlink
  81 } // end namespace llvm