[BACKEND] Allow nvptx to pass ll ir to CUDAModule (#404)

Author: tqchen

src/codegen/llvm/codegen_nvptx.cc

@@ -131,8 +131,7 @@ class CodeGenNVPTX : public CodeGenLLVM {
 };
 
 runtime::Module BuildNVPTX(Array<LoweredFunc> funcs, std::string target) {
-  CHECK(target.length(
-) >= 5 &&
+  CHECK(target.length() >= 5 &&
         target.substr(0, 5) == "nvptx");
   llvm::TargetMachine* tm = GetLLVMTargetMachine(
       "-mtriple=nvptx64-nvidia-cuda -mcpu=sm_20" +
@@ -144,16 +143,19 @@ runtime::Module BuildNVPTX(Array<LoweredFunc> funcs, std::string target) {
     cg->AddFunction(f);
   }
   std::unique_ptr<llvm::Module> module = cg->Finish();
-  llvm::SmallString<8> data;
-  llvm::raw_svector_ostream dest(data);
-  dest.SetUnbuffered();
+  llvm::SmallString<8> data_ptx, data_ll;
+  llvm::raw_svector_ostream dest_ptx(data_ptx), dest_ll(data_ll);
+  dest_ptx.SetUnbuffered();
+  dest_ll.SetUnbuffered();
   llvm::legacy::PassManager pass;
   CHECK(tm->addPassesToEmitFile(
-      pass, dest, llvm::TargetMachine::CGFT_AssemblyFile) == 0)
+      pass, dest_ptx, llvm::TargetMachine::CGFT_AssemblyFile) == 0)
       << "Cannot emit target CGFT_ObjectFile";
   pass.run(*module);
-  std::string ptx(data.begin(), data.end());
-  return CUDAModuleCreate(ptx, "ptx", ExtractFuncInfo(funcs), "");
+  module->print(dest_ll, nullptr);
+  std::string ptx(data_ptx.begin(), data_ptx.end());
+  std::string ll(data_ll.begin(), data_ll.end());
+  return CUDAModuleCreate(ptx, "ptx", ExtractFuncInfo(funcs), ll);
 }
 
 TVM_REGISTER_API("codegen.build_nvptx")