vendor/llvm-project/llvmorg-12-init-17869-g8e464dd76bef

1 files changed, 337 insertions, 0 deletions

diff --git a/llvm/lib/Object/MachOUniversalWriter.cpp b/llvm/lib/Object/MachOUniversalWriter.cpp
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index 000000000000..4bb467e56a6f
--- /dev/null
+++ b/llvm/lib/Object/MachOUniversalWriter.cpp
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+//===- MachOUniversalWriter.cpp - MachO universal binary writer---*- C++-*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Defines the Slice class and writeUniversalBinary function for writing a MachO
+// universal binary file.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Object/MachOUniversalWriter.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Object/Archive.h"
+#include "llvm/Object/Binary.h"
+#include "llvm/Object/Error.h"
+#include "llvm/Object/IRObjectFile.h"
+#include "llvm/Object/MachO.h"
+#include "llvm/Object/MachOUniversal.h"
+#include "llvm/Support/SmallVectorMemoryBuffer.h"
+
+using namespace llvm;
+using namespace object;
+
+// For compatibility with cctools lipo, a file's alignment is calculated as the
+// minimum aligment of all segments. For object files, the file's alignment is
+// the maximum alignment of its sections.
+static uint32_t calculateFileAlignment(const MachOObjectFile &O) {
+  uint32_t P2CurrentAlignment;
+  uint32_t P2MinAlignment = MachOUniversalBinary::MaxSectionAlignment;
+  const bool Is64Bit = O.is64Bit();
+
+  for (const auto &LC : O.load_commands()) {
+    if (LC.C.cmd != (Is64Bit ? MachO::LC_SEGMENT_64 : MachO::LC_SEGMENT))
+      continue;
+    if (O.getHeader().filetype == MachO::MH_OBJECT) {
+      unsigned NumberOfSections =
+          (Is64Bit ? O.getSegment64LoadCommand(LC).nsects
+                   : O.getSegmentLoadCommand(LC).nsects);
+      P2CurrentAlignment = NumberOfSections ? 2 : P2MinAlignment;
+      for (unsigned SI = 0; SI < NumberOfSections; ++SI) {
+        P2CurrentAlignment = std::max(P2CurrentAlignment,
+                                      (Is64Bit ? O.getSection64(LC, SI).align
+                                               : O.getSection(LC, SI).align));
+      }
+    } else {
+      P2CurrentAlignment =
+          countTrailingZeros(Is64Bit ? O.getSegment64LoadCommand(LC).vmaddr
+                                     : O.getSegmentLoadCommand(LC).vmaddr);
+    }
+    P2MinAlignment = std::min(P2MinAlignment, P2CurrentAlignment);
+  }
+  // return a value >= 4 byte aligned, and less than MachO MaxSectionAlignment
+  return std::max(
+      static_cast<uint32_t>(2),
+      std::min(P2MinAlignment, static_cast<uint32_t>(
+                                   MachOUniversalBinary::MaxSectionAlignment)));
+}
+
+static uint32_t calculateAlignment(const MachOObjectFile &ObjectFile) {
+  switch (ObjectFile.getHeader().cputype) {
+  case MachO::CPU_TYPE_I386:
+  case MachO::CPU_TYPE_X86_64:
+  case MachO::CPU_TYPE_POWERPC:
+  case MachO::CPU_TYPE_POWERPC64:
+    return 12; // log2 value of page size(4k) for x86 and PPC
+  case MachO::CPU_TYPE_ARM:
+  case MachO::CPU_TYPE_ARM64:
+  case MachO::CPU_TYPE_ARM64_32:
+    return 14; // log2 value of page size(16k) for Darwin ARM
+  default:
+    return calculateFileAlignment(ObjectFile);
+  }
+}
+
+Slice::Slice(const Archive &A, uint32_t CPUType, uint32_t CPUSubType,
+             std::string ArchName, uint32_t Align)
+    : B(&A), CPUType(CPUType), CPUSubType(CPUSubType),
+      ArchName(std::move(ArchName)), P2Alignment(Align) {}
+
+Slice::Slice(const MachOObjectFile &O, uint32_t Align)
+    : B(&O), CPUType(O.getHeader().cputype),
+      CPUSubType(O.getHeader().cpusubtype),
+      ArchName(std::string(O.getArchTriple().getArchName())),
+      P2Alignment(Align) {}
+
+Slice::Slice(const IRObjectFile &IRO, uint32_t CPUType, uint32_t CPUSubType,
+             std::string ArchName, uint32_t Align)
+    : B(&IRO), CPUType(CPUType), CPUSubType(CPUSubType),
+      ArchName(std::move(ArchName)), P2Alignment(Align) {}
+
+Slice::Slice(const MachOObjectFile &O) : Slice(O, calculateAlignment(O)) {}
+
+using MachoCPUTy = std::pair<unsigned, unsigned>;
+
+static Expected<MachoCPUTy> getMachoCPUFromTriple(Triple TT) {
+  auto CPU = std::make_pair(MachO::getCPUType(TT), MachO::getCPUSubType(TT));
+  if (!CPU.first) {
+    return CPU.first.takeError();
+  }
+  if (!CPU.second) {
+    return CPU.second.takeError();
+  }
+  return std::make_pair(*CPU.first, *CPU.second);
+}
+
+static Expected<MachoCPUTy> getMachoCPUFromTriple(StringRef TT) {
+  return getMachoCPUFromTriple(Triple{TT});
+}
+
+Expected<Slice> Slice::create(const Archive &A, LLVMContext *LLVMCtx) {
+  Error Err = Error::success();
+  std::unique_ptr<MachOObjectFile> MFO = nullptr;
+  std::unique_ptr<IRObjectFile> IRFO = nullptr;
+  for (const Archive::Child &Child : A.children(Err)) {
+    Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary(LLVMCtx);
+    if (!ChildOrErr)
+      return createFileError(A.getFileName(), ChildOrErr.takeError());
+    Binary *Bin = ChildOrErr.get().get();
+    if (Bin->isMachOUniversalBinary())
+      return createStringError(std::errc::invalid_argument,
+                               ("archive member " + Bin->getFileName() +
+                                " is a fat file (not allowed in an archive)")
+                                   .str()
+                                   .c_str());
+    if (Bin->isMachO()) {
+      MachOObjectFile *O = cast<MachOObjectFile>(Bin);
+      if (IRFO) {
+        return createStringError(
+            std::errc::invalid_argument,
+            "archive member %s is a MachO, while previous archive member "
+            "%s was an IR LLVM object",
+            O->getFileName().str().c_str(), IRFO->getFileName().str().c_str());
+      }
+      if (MFO &&
+          std::tie(MFO->getHeader().cputype, MFO->getHeader().cpusubtype) !=
+              std::tie(O->getHeader().cputype, O->getHeader().cpusubtype)) {
+        return createStringError(
+            std::errc::invalid_argument,
+            ("archive member " + O->getFileName() + " cputype (" +
+             Twine(O->getHeader().cputype) + ") and cpusubtype(" +
+             Twine(O->getHeader().cpusubtype) +
+             ") does not match previous archive members cputype (" +
+             Twine(MFO->getHeader().cputype) + ") and cpusubtype(" +
+             Twine(MFO->getHeader().cpusubtype) +
+             ") (all members must match) " + MFO->getFileName())
+                .str()
+                .c_str());
+      }
+      if (!MFO) {
+        ChildOrErr.get().release();
+        MFO.reset(O);
+      }
+    } else if (Bin->isIR()) {
+      IRObjectFile *O = cast<IRObjectFile>(Bin);
+      if (MFO) {
+        return createStringError(std::errc::invalid_argument,
+                                 "archive member '%s' is an LLVM IR object, "
+                                 "while previous archive member "
+                                 "'%s' was a MachO",
+                                 O->getFileName().str().c_str(),
+                                 MFO->getFileName().str().c_str());
+      }
+      if (IRFO) {
+        Expected<MachoCPUTy> CPUO = getMachoCPUFromTriple(O->getTargetTriple());
+        Expected<MachoCPUTy> CPUFO =
+            getMachoCPUFromTriple(IRFO->getTargetTriple());
+        if (!CPUO)
+          return CPUO.takeError();
+        if (!CPUFO)
+          return CPUFO.takeError();
+        if (*CPUO != *CPUFO) {
+          return createStringError(
+              std::errc::invalid_argument,
+              ("archive member " + O->getFileName() + " cputype (" +
+               Twine(CPUO->first) + ") and cpusubtype(" + Twine(CPUO->second) +
+               ") does not match previous archive members cputype (" +
+               Twine(CPUFO->first) + ") and cpusubtype(" +
+               Twine(CPUFO->second) + ") (all members must match) " +
+               IRFO->getFileName())
+                  .str()
+                  .c_str());
+        }
+      } else {
+        ChildOrErr.get().release();
+        IRFO.reset(O);
+      }
+    } else
+      return createStringError(std::errc::invalid_argument,
+                               ("archive member " + Bin->getFileName() +
+                                " is neither a MachO file or an LLVM IR file "
+                                "(not allowed in an archive)")
+                                   .str()
+                                   .c_str());
+  }
+  if (Err)
+    return createFileError(A.getFileName(), std::move(Err));
+  if (!MFO && !IRFO)
+    return createStringError(
+        std::errc::invalid_argument,
+        ("empty archive with no architecture specification: " +
+         A.getFileName() + " (can't determine architecture for it)")
+            .str()
+            .c_str());
+
+  if (MFO) {
+    Slice ArchiveSlice(*(MFO.get()), MFO->is64Bit() ? 3 : 2);
+    ArchiveSlice.B = &A;
+    return ArchiveSlice;
+  }
+
+  // For IR objects
+  Expected<Slice> ArchiveSliceOrErr = Slice::create(*IRFO, 0);
+  if (!ArchiveSliceOrErr)
+    return createFileError(A.getFileName(), ArchiveSliceOrErr.takeError());
+  auto &ArchiveSlice = ArchiveSliceOrErr.get();
+  ArchiveSlice.B = &A;
+  return std::move(ArchiveSlice);
+}
+
+Expected<Slice> Slice::create(const IRObjectFile &IRO, uint32_t Align) {
+  Expected<MachoCPUTy> CPUOrErr = getMachoCPUFromTriple(IRO.getTargetTriple());
+  if (!CPUOrErr)
+    return CPUOrErr.takeError();
+  unsigned CPUType, CPUSubType;
+  std::tie(CPUType, CPUSubType) = CPUOrErr.get();
+  // We don't directly use the architecture name of the target triple T, as,
+  // for instance, thumb is treated as ARM by the MachOUniversal object.
+  std::string ArchName(
+      MachOObjectFile::getArchTriple(CPUType, CPUSubType).getArchName());
+  return Slice{IRO, CPUType, CPUSubType, std::move(ArchName), Align};
+}
+
+static Expected<SmallVector<MachO::fat_arch, 2>>
+buildFatArchList(ArrayRef<Slice> Slices) {
+  SmallVector<MachO::fat_arch, 2> FatArchList;
+  uint64_t Offset =
+      sizeof(MachO::fat_header) + Slices.size() * sizeof(MachO::fat_arch);
+
+  for (const auto &S : Slices) {
+    Offset = alignTo(Offset, 1ull << S.getP2Alignment());
+    if (Offset > UINT32_MAX)
+      return createStringError(
+          std::errc::invalid_argument,
+          ("fat file too large to be created because the offset "
+           "field in struct fat_arch is only 32-bits and the offset " +
+           Twine(Offset) + " for " + S.getBinary()->getFileName() +
+           " for architecture " + S.getArchString() + "exceeds that.")
+              .str()
+              .c_str());
+
+    MachO::fat_arch FatArch;
+    FatArch.cputype = S.getCPUType();
+    FatArch.cpusubtype = S.getCPUSubType();
+    FatArch.offset = Offset;
+    FatArch.size = S.getBinary()->getMemoryBufferRef().getBufferSize();
+    FatArch.align = S.getP2Alignment();
+    Offset += FatArch.size;
+    FatArchList.push_back(FatArch);
+  }
+  return FatArchList;
+}
+
+static Error writeUniversalBinaryToStream(ArrayRef<Slice> Slices,
+                                          raw_ostream &Out) {
+  MachO::fat_header FatHeader;
+  FatHeader.magic = MachO::FAT_MAGIC;
+  FatHeader.nfat_arch = Slices.size();
+
+  Expected<SmallVector<MachO::fat_arch, 2>> FatArchListOrErr =
+      buildFatArchList(Slices);
+  if (!FatArchListOrErr)
+    return FatArchListOrErr.takeError();
+  SmallVector<MachO::fat_arch, 2> FatArchList = *FatArchListOrErr;
+
+  if (sys::IsLittleEndianHost)
+    MachO::swapStruct(FatHeader);
+  Out.write(reinterpret_cast<const char *>(&FatHeader),
+            sizeof(MachO::fat_header));
+
+  if (sys::IsLittleEndianHost)
+    for (MachO::fat_arch &FA : FatArchList)
+      MachO::swapStruct(FA);
+  Out.write(reinterpret_cast<const char *>(FatArchList.data()),
+            sizeof(MachO::fat_arch) * FatArchList.size());
+
+  if (sys::IsLittleEndianHost)
+    for (MachO::fat_arch &FA : FatArchList)
+      MachO::swapStruct(FA);
+
+  size_t Offset =
+      sizeof(MachO::fat_header) + sizeof(MachO::fat_arch) * FatArchList.size();
+  for (size_t Index = 0, Size = Slices.size(); Index < Size; ++Index) {
+    MemoryBufferRef BufferRef = Slices[Index].getBinary()->getMemoryBufferRef();
+    assert((Offset <= FatArchList[Index].offset) && "Incorrect slice offset");
+    Out.write_zeros(FatArchList[Index].offset - Offset);
+    Out.write(BufferRef.getBufferStart(), BufferRef.getBufferSize());
+    Offset = FatArchList[Index].offset + BufferRef.getBufferSize();
+  }
+
+  Out.flush();
+  return Error::success();
+}
+
+Error object::writeUniversalBinary(ArrayRef<Slice> Slices,
+                                   StringRef OutputFileName) {
+  const bool IsExecutable = any_of(Slices, [](Slice S) {
+    return sys::fs::can_execute(S.getBinary()->getFileName());
+  });
+  unsigned Mode = sys::fs::all_read | sys::fs::all_write;
+  if (IsExecutable)
+    Mode |= sys::fs::all_exe;
+  Expected<sys::fs::TempFile> Temp = sys::fs::TempFile::create(
+      OutputFileName + ".temp-universal-%%%%%%", Mode);
+  if (!Temp)
+    return Temp.takeError();
+  raw_fd_ostream Out(Temp->FD, false);
+  if (Error E = writeUniversalBinaryToStream(Slices, Out)) {
+    if (Error DiscardError = Temp->discard())
+      return joinErrors(std::move(E), std::move(DiscardError));
+    return E;
+  }
+  return Temp->keep(OutputFileName);
+}
+
+Expected<std::unique_ptr<MemoryBuffer>>
+object::writeUniversalBinaryToBuffer(ArrayRef<Slice> Slices) {
+  SmallVector<char, 0> Buffer;
+  raw_svector_ostream Out(Buffer);
+
+  if (Error E = writeUniversalBinaryToStream(Slices, Out))
+    return std::move(E);
+
+  return std::make_unique<SmallVectorMemoryBuffer>(std::move(Buffer));
+}