If all linker input files are native object files then lto-bugpoint is not useful.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53777 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/lto-bugpoint/LTOBugPoint.cpp b/tools/lto-bugpoint/LTOBugPoint.cpp
index 83ed134..925ab9e 100644
--- a/tools/lto-bugpoint/LTOBugPoint.cpp
+++ b/tools/lto-bugpoint/LTOBugPoint.cpp
@@ -13,7 +13,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "LTOBugPoint.h"
+#include "llvm/Support/SystemUtils.h"
+#include "llvm/System/Path.h"
+#include <iostream>
 
+/// LTOBugPoint -- Constructor. Popuate list of linker options and
+/// list of linker input files.
 LTOBugPoint::LTOBugPoint(std::istream &args, std::istream &ins) {
 
   // Read linker options. Order is important here.
@@ -26,3 +31,27 @@
   while(getline(ins, inFile))
     LinkerInputFiles.push_back(inFile);
 }
+
+/// findTroubleMakers - Find minimum set of input files that causes error
+/// identified by the script.
+bool
+LTOBugPoint::findTroubleMakers(llvm::SmallVector<std::string, 4> &TroubleMakers,
+			       std::string &Script) {
+
+  // First, build native object files set.
+  bool bitcodeFileSeen = false;
+  for(llvm::SmallVector<std::string, 16>::iterator I = LinkerInputFiles.begin(),
+	E = LinkerInputFiles.end(); I != E; ++I) {
+    std::string &path = *I;
+    if (llvm::sys::Path(path.c_str()).isBitcodeFile()) 
+      bitcodeFileSeen = true;
+  }
+
+  if (!bitcodeFileSeen) {
+    std::cerr << "lto-bugpoint: Error: Unable to help!"; 
+    std::cerr << " Need at least one input file that contains llvm bitcode\n";
+    return false;
+  }
+
+  return true;
+}