Re-apply: [obj2yaml] [yaml2obj] Support MachO section and section_64

This re-applies r269845, r269846, and r269850 with an included fix for a crash reported by zturner.

llvm-svn: 269953

2 files changed, 86 insertions, 0 deletions

diff --git a/llvm/tools/obj2yaml/macho2yaml.cpp b/llvm/tools/obj2yaml/macho2yaml.cpp
index cbf55ba35a5..66244c30e40 100644
--- a/llvm/tools/obj2yaml/macho2yaml.cpp
+++ b/llvm/tools/obj2yaml/macho2yaml.cpp
@@ -13,6 +13,8 @@
 #include "llvm/ObjectYAML/MachOYAML.h"
 #include "llvm/Support/ErrorHandling.h"
 
+#include <string.h> // for memcpy
+
 using namespace llvm;
 
 class MachODumper {
@@ -32,6 +34,24 @@ public:
       MachO::swapStruct(LC.Data.LCStruct##_data);                              \
     break;
 
+template <typename SectionType>
+MachOYAML::Section constructSection(SectionType Sec) {
+  MachOYAML::Section TempSec;
+  memcpy(reinterpret_cast<void *>(&TempSec.sectname[0]), &Sec.sectname[0], 16);
+  memcpy(reinterpret_cast<void *>(&TempSec.segname[0]), &Sec.segname[0], 16);
+  TempSec.addr = Sec.addr;
+  TempSec.size = Sec.size;
+  TempSec.offset = Sec.offset;
+  TempSec.align = Sec.align;
+  TempSec.reloff = Sec.reloff;
+  TempSec.nreloc = Sec.nreloc;
+  TempSec.flags = Sec.flags;
+  TempSec.reserved1 = Sec.reserved1;
+  TempSec.reserved2 = Sec.reserved2;
+  TempSec.reserved3 = 0;
+  return TempSec;
+}
+
 Expected<std::unique_ptr<MachOYAML::Object>> MachODumper::dump() {
   auto Y = make_unique<MachOYAML::Object>();
   Y->Header.magic = Obj.getHeader().magic;
@@ -54,6 +74,40 @@ Expected<std::unique_ptr<MachOYAML::Object>> MachODumper::dump() {
       break;
 #include "llvm/Support/MachO.def"
     }
+    if (LoadCmd.C.cmd == MachO::LC_SEGMENT) {
+      auto End = LoadCmd.Ptr + LoadCmd.C.cmdsize;
+      const MachO::section *Curr = reinterpret_cast<const MachO::section *>(
+          LoadCmd.Ptr + sizeof(MachO::segment_command));
+      for (; reinterpret_cast<const void *>(Curr) < End; Curr++) {
+        if (Obj.isLittleEndian() != sys::IsLittleEndianHost) {
+          MachO::section Sec;
+          memcpy((void *)&Sec, Curr, sizeof(MachO::section));
+          MachO::swapStruct(Sec);
+          LC.Sections.push_back(constructSection(Sec));
+        } else {
+          LC.Sections.push_back(constructSection(*Curr));
+        }
+      }
+    } else if (LoadCmd.C.cmd == MachO::LC_SEGMENT_64) {
+      auto End = LoadCmd.Ptr + LoadCmd.C.cmdsize;
+      const MachO::section_64 *Curr =
+          reinterpret_cast<const MachO::section_64 *>(
+              LoadCmd.Ptr + sizeof(MachO::segment_command_64));
+      for (; reinterpret_cast<const void *>(Curr) < End; Curr++) {
+        MachOYAML::Section TempSec;
+        if (Obj.isLittleEndian() != sys::IsLittleEndianHost) {
+          MachO::section_64 Sec;
+          memcpy((void *)&Sec, Curr, sizeof(MachO::section_64));
+          MachO::swapStruct(Sec);
+          LC.Sections.push_back(constructSection(Sec));
+          TempSec = constructSection(Sec);
+        } else {
+          TempSec = constructSection(*Curr);
+        }
+        TempSec.reserved3 = Curr->reserved3;
+        LC.Sections.push_back(TempSec);
+      }
+    }
     Y->LoadCommands.push_back(std::move(LC));
   }
 
diff --git a/llvm/tools/yaml2obj/yaml2macho.cpp b/llvm/tools/yaml2obj/yaml2macho.cpp
index 772c710c098..0e8799e2ce1 100644
--- a/llvm/tools/yaml2obj/yaml2macho.cpp
+++ b/llvm/tools/yaml2obj/yaml2macho.cpp
@@ -77,6 +77,23 @@ Error MachOWriter::writeHeader(raw_ostream &OS) {
   return Error::success();
 }
 
+template <typename SectionType>
+SectionType constructSection(MachOYAML::Section Sec) {
+  SectionType TempSec;
+  memcpy(reinterpret_cast<void *>(&TempSec.sectname[0]), &Sec.sectname[0], 16);
+  memcpy(reinterpret_cast<void *>(&TempSec.segname[0]), &Sec.segname[0], 16);
+  TempSec.addr = Sec.addr;
+  TempSec.size = Sec.size;
+  TempSec.offset = Sec.offset;
+  TempSec.align = Sec.align;
+  TempSec.reloff = Sec.reloff;
+  TempSec.nreloc = Sec.nreloc;
+  TempSec.flags = Sec.flags;
+  TempSec.reserved1 = Sec.reserved1;
+  TempSec.reserved2 = Sec.reserved2;
+  return TempSec;
+}
+
 Error MachOWriter::writeLoadCommands(raw_ostream &OS) {
   for (auto &LC : Obj.LoadCommands) {
     size_t BytesWritten = 0;
@@ -96,6 +113,21 @@ Error MachOWriter::writeLoadCommands(raw_ostream &OS) {
 #include "llvm/Support/MachO.def"
     }
 
+    if(LC.Data.load_command_data.cmd == MachO::LC_SEGMENT) {
+      for(auto Sec : LC.Sections) {
+        auto TempSec = constructSection<MachO::section>(Sec);
+        OS.write(reinterpret_cast<const char *>(&(TempSec)), sizeof(MachO::section));
+        BytesWritten += sizeof(MachO::section);
+      }
+    } else if(LC.Data.load_command_data.cmd == MachO::LC_SEGMENT_64) {
+      for(auto Sec : LC.Sections) {
+        auto TempSec = constructSection<MachO::section_64>(Sec);
+        TempSec.reserved3 = Sec.reserved3;
+        OS.write(reinterpret_cast<const char *>(&(TempSec)), sizeof(MachO::section_64));
+        BytesWritten += sizeof(MachO::section_64);
+      }
+    }
+
     auto BytesRemaining =
         LC.Data.load_command_data.cmdsize - BytesWritten;
     if (BytesRemaining > 0) {