[llvm-objcopy][MachO] Support indirect symbol table

Summary:
Parse the indirect symbol table and update the indexes of
symbol entries in the table in the writer in case they have
been changed.

Reviewers: alexshap, rupprecht, jhenderson

Reviewed By: alexshap, rupprecht

Subscribers: jakehehrlich, abrachet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66280

1 files changed, 8 insertions, 5 deletions

diff --git a/llvm/tools/llvm-objcopy/MachO/MachOWriter.cpp b/llvm/tools/llvm-objcopy/MachO/MachOWriter.cpp
index 4ec91cc9eb7..59d57f7f2db 100644
--- a/llvm/tools/llvm-objcopy/MachO/MachOWriter.cpp
+++ b/llvm/tools/llvm-objcopy/MachO/MachOWriter.cpp
@@ -369,11 +369,14 @@ void MachOWriter::writeIndirectSymbolTable() {
       O.LoadCommands[*O.DySymTabCommandIndex]
           .MachOLoadCommand.dysymtab_command_data;
 
-  char *Out = (char *)B.getBufferStart() + DySymTabCommand.indirectsymoff;
-  assert((DySymTabCommand.nindirectsyms == O.IndirectSymTable.Symbols.size()) &&
-         "Incorrect indirect symbol table size");
-  memcpy(Out, O.IndirectSymTable.Symbols.data(),
-         sizeof(uint32_t) * O.IndirectSymTable.Symbols.size());
+  uint32_t *Out =
+      (uint32_t *)(B.getBufferStart() + DySymTabCommand.indirectsymoff);
+  for (const IndirectSymbolEntry &Sym : O.IndirectSymTable.Symbols) {
+    uint32_t Entry = (Sym.Symbol) ? (*Sym.Symbol)->Index : Sym.OriginalIndex;
+    if (IsLittleEndian != sys::IsLittleEndianHost)
+      sys::swapByteOrder(Entry);
+    *Out++ = Entry;
+  }
 }
 
 void MachOWriter::writeDataInCodeData() {