Implement LLVM JIT side of GDB JIT debugging interface

lib/ExecutionEngine/JIT/JITDebugRegisterer.cpp

 //===-- JITDebugRegisterer.cpp - Register debug symbols for JIT -----------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file defines a JITDebugRegisterer object that is used by the JIT to
@@ skipping 88 matching lines @@
 
   // Add this single function to the symbol table, so the debugger prints the
   // name instead of '???'.  We give the symbol default global visibility.
   ELFSym *FnSym = ELFSym::getGV(F,
                                 ELFSym::STB_GLOBAL,
                                 ELFSym::STT_FUNC,
                                 ELFSym::STV_DEFAULT);
   FnSym->SectionIdx = Text.SectionIdx;
   FnSym->Size = I.FnEnd - I.FnStart;
   FnSym->Value = 0;  // Offset from start of section.
-  // TODO(rnk): Until bruno fixes the ELFWriter to not leak the ELFSym objects,
-  // we will leak this pointer.
   EW.SymbolList.push_back(FnSym);
 
   EW.doFinalization(M);
   O.flush();
 
   // When trying to debug this code, it's awfully helpful to write the object
   // file to disk.
-  //std::string Filename;
-  //raw_string_ostream O2(Filename);
-  //O2 << "/tmp/llvm_function_" << I.FnStart << "_" << F->getNameStr() << ".o";
-  //O2.flush();
-  //std::string Errors;
-  //raw_fd_ostream O3(Filename.c_str(), /*Binary=*/true, /*Forced=*/true,
-  //                  Errors);
-  //O3 << Buffer;
-  //O3.close();
+  std::string Filename;
+  raw_string_ostream O2(Filename);
+  O2 << "/tmp/llvm_function_" << I.FnStart << "_" << F->getNameStr() << ".o";
+  O2.flush();
+  std::string Errors;
+  raw_fd_ostream O3(Filename.c_str(), Errors);
+  O3 << Buffer;
+  O3.close();
 
   return Buffer;
 }
 
 void JITDebugRegisterer::RegisterFunction(const Function *F, DebugInfo &I) {
+  // TODO: Support non-ELF platforms.
+  if (!TM.getELFWriterInfo())
+    return;
+
   std::string Buffer = MakeELF(F, I);
 
   jit_code_entry *JITCodeEntry = new jit_code_entry();
   JITCodeEntry->symfile_addr = Buffer.c_str();
   JITCodeEntry->symfile_size = Buffer.size();
 
   // Add a mapping from F to the entry and buffer, so we can delete this
   // info later.
   FnMap[F] = std::make_pair<std::string, jit_code_entry*>(Buffer, JITCodeEntry);
 
@@ skipping 41 matching lines @@
     __jit_debug_descriptor.relevant_entry = JITCodeEntry;
     __jit_debug_register_code();
   }
 
   // Free the ELF file in memory.
   std::string &Buffer = I->second.first;
   Buffer.clear();
 }
 
 void JITDebugRegisterer::UnregisterFunction(const Function *F) {
+  // TODO: Support non-ELF platforms.
+  if (!TM.getELFWriterInfo())
+    return;
+
   RegisteredFunctionsMap::iterator I = FnMap.find(F);
   if (I == FnMap.end()) return;
   UnregisterFunctionInternal(I);
   FnMap.erase(I);
 }
 
 } // end namespace llvm