llvm/lib/ExecutionEngine/JITLink/MachO.cpp

   1 //===-------------- MachO.cpp - JIT linker function for MachO -------------===//
   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 // MachO jit-link function.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "llvm/ExecutionEngine/JITLink/MachO.h"
  14
  15 #include "llvm/BinaryFormat/MachO.h"
  16 #include "llvm/ExecutionEngine/JITLink/MachO_arm64.h"
  17 #include "llvm/ExecutionEngine/JITLink/MachO_x86_64.h"
  18 #include "llvm/Support/Format.h"
  19 #include "llvm/Support/MemoryBuffer.h"
  20 #include "llvm/Support/SwapByteOrder.h"
  21
  22 using namespace llvm;
  23
  24 #define DEBUG_TYPE "jitlink"
  25
  26 namespace llvm {
  27 namespace jitlink {
  28
  29 Expected<std::unique_ptr<LinkGraph>>
  30 createLinkGraphFromMachOObject(MemoryBufferRef ObjectBuffer) {
  31   StringRef Data = ObjectBuffer.getBuffer();
  32   if (Data.size() < 4)
  33     return make_error<JITLinkError>("Truncated MachO buffer \"" +
  34                                     ObjectBuffer.getBufferIdentifier() + "\"");
  35
  36   uint32_t Magic;
  37   memcpy(&Magic, Data.data(), sizeof(uint32_t));
  38   LLVM_DEBUG({
  39     dbgs() << "jitLink_MachO: magic = " << format("0x%08" PRIx32, Magic)
  40            << ", identifier = \"" << ObjectBuffer.getBufferIdentifier()
  41            << "\"\n";
  42   });
  43
  44   if (Magic == MachO::MH_MAGIC || Magic == MachO::MH_CIGAM)
  45     return make_error<JITLinkError>("MachO 32-bit platforms not supported");
  46   else if (Magic == MachO::MH_MAGIC_64 || Magic == MachO::MH_CIGAM_64) {
  47
  48     if (Data.size() < sizeof(MachO::mach_header_64))
  49       return make_error<JITLinkError>("Truncated MachO buffer \"" +
  50                                       ObjectBuffer.getBufferIdentifier() +
  51                                       "\"");
  52
  53     // Read the CPU type from the header.
  54     uint32_t CPUType;
  55     memcpy(&CPUType, Data.data() + 4, sizeof(uint32_t));
  56     if (Magic == MachO::MH_CIGAM_64)
  57       CPUType = ByteSwap_32(CPUType);
  58
  59     LLVM_DEBUG({
  60       dbgs() << "jitLink_MachO: cputype = " << format("0x%08" PRIx32, CPUType)
  61              << "\n";
  62     });
  63
  64     switch (CPUType) {
  65     case MachO::CPU_TYPE_ARM64:
  66       return createLinkGraphFromMachOObject_arm64(ObjectBuffer);
  67     case MachO::CPU_TYPE_X86_64:
  68       return createLinkGraphFromMachOObject_x86_64(ObjectBuffer);
  69     }
  70     return make_error<JITLinkError>("MachO-64 CPU type not valid");
  71   } else
  72     return make_error<JITLinkError>("Unrecognized MachO magic value");
  73 }
  74
  75 void link_MachO(std::unique_ptr<LinkGraph> G,
  76                 std::unique_ptr<JITLinkContext> Ctx) {
  77
  78   switch (G->getTargetTriple().getArch()) {
  79   case Triple::aarch64:
  80     return link_MachO_arm64(std::move(G), std::move(Ctx));
  81   case Triple::x86_64:
  82     return link_MachO_x86_64(std::move(G), std::move(Ctx));
  83   default:
  84     Ctx->notifyFailed(make_error<JITLinkError>("MachO-64 CPU type not valid"));
  85     return;
  86   }
  87 }
  88
  89 } // end namespace jitlink
  90 } // end namespace llvm