basic_functions fixes

include/bcdb/BCDB.h

@@ -46,6 +46,8 @@ class BCDB {
 
   llvm::Expected<std::unique_ptr<llvm::Module>>
   LoadParts(llvm::StringRef Name, std::map<std::string, std::string> &PartIDs);
+
+  llvm::Expected<std::vector<std::string>> FetchBasicFunctions(std::string dest_path);
 };
 
 } // end namespace bcdb

lib/BCDB/BCDB.cpp

@@ -3,6 +3,8 @@
 #include "bcdb/AlignBitcode.h"
 #include "bcdb/Split.h"
 
+#include "llvm/Support/TarWriter.h"
+
 #include <llvm/Bitcode/BitcodeReader.h>
 #include <llvm/Bitcode/BitcodeWriter.h>
 #include <llvm/IR/Constants.h>
@@ -259,6 +261,35 @@ Expected<std::unique_ptr<Module>> BCDB::GetFunctionById(StringRef Id) {
   return LoadModuleFromValue(db.get(), value.get(), Id, Context);
 }
 
+
+Expected<std::vector<std::string>> BCDB::FetchBasicFunctions(std::string dest_path) {
+  Expected<std::unique_ptr<TarWriter>> tar_writer = TarWriter::create(dest_path, "basic_functions");
+  if(!tar_writer) return tar_writer.takeError();
+
+  std::vector<std::string> basic_functions;
+  Expected<std::vector<std::string>> all_functions = ListAllFunctions();
+  if(!all_functions) return all_functions.takeError();
+  for (auto &func_id : *all_functions){
+    auto M = GetFunctionById(func_id);
+    if (!M) return M.takeError();
+    for (Function &F : **M) {
+      //skip declarations
+      if (!F.isDeclaration()){
+        if(F.size() == 1){
+          SmallVector<char, 0> Buffer;
+          WriteUnalignedModule(**M, Buffer);
+          basic_functions.push_back(func_id);
+          //append file to archive
+          std::string basic_func(Buffer.begin(), Buffer.end());
+          (*tar_writer)->append(func_id + ".bc", basic_func);
+        }
+      }
+    }
+  }
+  return basic_functions;
+}
+
+
 namespace {
 class BCDBSplitLoader : public SplitLoader {
   LLVMContext &Context;

tools/bcdb/bcdb.cpp

@@ -247,6 +247,26 @@ static int Mux() {
   return WriteModule(*M);
 }
 
+//bcdb FetchBasicFunctions
+
+static cl::SubCommand ExtractBasicCommand("extract-basic-functions", "Extract basic functions to destination");
+
+static cl::opt<std::string> DestPath("dest_path", cl::desc("full destination path"),
+                                  cl::sub(ExtractBasicCommand), cl::Required);
+
+static int ExtractBasicFunctions(){
+  ExitOnError Err("bcdb extractbasicfunctions: ");
+  std::unique_ptr<BCDB> db = Err(BCDB::Open(Uri));
+  std::string dest_path = DestPath;
+  std::vector<std::string> basicfuncs = Err(db->FetchBasicFunctions(dest_path));
+  outs() <<"Extracting "<< basicfuncs.size() <<" functions to "<< dest_path <<"\n";
+  for (auto &basicfunc : basicfuncs) {
+    outs() << basicfunc << "\n";
+  }
+  return 0;
+}
+
+
 // main
 
 int main(int argc, char **argv) {
@@ -275,6 +295,8 @@ int main(int argc, char **argv) {
     return Merge();
   } else if (MuxCommand) {
     return Mux();
+  } else if (ExtractBasicCommand){
+    return ExtractBasicFunctions();
   } else {
     cl::PrintHelpMessage(false, true);
     return 0;