Adding FindBugs.cpp so the -find-bugs option will work.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29704 91177308-0d34-0410-b5e6-96231b3b80d8

tools/bugpoint/FindBugs.cpp

@@ -0,0 +1,119 @@
+//===-- FindBugs.cpp - Run Many Different Optimizations -------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Patrick Jenkins and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines an interface that allows bugpoint to choose different 
+// combinations of optimizations to run on the selected input. Bugpoint will 
+// run these optimizations and record the success/failure of each. This way
+// we can hopefully spot bugs in the optimizations.
+//
+//===----------------------------------------------------------------------===//
+#include "BugDriver.h"
+#include "ToolRunner.h"
+
+#include "llvm/Bytecode/WriteBytecodePass.h"
+
+#include <algorithm>
+#include <ctime>
+using namespace llvm;
+
+/// runManyPasses - Take the specified pass list and create different 
+/// combinations of passes to compile the program with. Compile the program with
+/// each set and mark test to see if it compiled correctly. If the passes 
+/// compiled correctly output nothing and rearrange the passes into a new order.
+/// If the passes did not compile correctly, output the command required to 
+/// recreate the failure. This returns true if a compiler error is found.
+///
+bool BugDriver::runManyPasses(const std::vector<const PassInfo*> &AllPasses)
+{
+  std::string Filename;
+  std::vector<const PassInfo*> TempPass(AllPasses);
+  std::cout << "Starting bug finding procedure...\n\n";
+  
+  // Creating a reference output if necessary
+  if (initializeExecutionEnvironment()) return false;
+  std::cout << "\n";
+  if (ReferenceOutputFile.empty()) {
+  	std::cout << "Generating reference output from raw program: \n";
+	  if(!createReferenceFile(Program)){
+	  	return false;
+	  }
+  }
+  
+  srand(time(NULL));  
+  std::vector<const PassInfo*>::iterator I = TempPass.begin();
+  std::vector<const PassInfo*>::iterator E = TempPass.end();
+
+	int num=1;
+  while(1){  
+    //
+    // Step 1: Randomize the order of the optimizer passes.
+    //
+    std::random_shuffle(TempPass.begin(), TempPass.end());
+    
+    //
+    // Step 2: Run optimizer passes on the program and check for success.
+    //
+    std::cout << "Running selected passes on program to test for crash: ";
+    for(int i=0, e=TempPass.size(); i!=e; i++) {
+      std::cout << "-" << TempPass[i]->getPassArgument( )<< " ";
+    }
+    std::string Filename;
+    if(runPasses(TempPass, Filename, false)) {
+      std::cout << "\n";
+      std::cout << "Optimizer passes caused failure!\n\n";
+      debugOptimizerCrash();
+      return true;
+    }
+    else{
+     std::cout << "Combination "<<num<<" optimized successfully!\n";
+    }
+     
+    //
+    // Step 3: Compile the optimized code.
+    //
+    std::cout << "Running the code generator to test for a crash: ";
+    try {
+      compileProgram(Program);
+      std::cout << '\n';
+    } catch (ToolExecutionError &TEE) {
+      std::cout << "\n*** compileProgram threw an exception: ";
+      std::cout << TEE.what();
+      return debugCodeGeneratorCrash();
+    }
+     
+    //
+    // Step 4: Run the program and compare its output to the reference 
+    // output (created above).
+    //
+    std::cout << "*** Checking if passes caused miscompliation:\n";
+    try {
+      if (diffProgram(Filename, "", false)) {
+        std::cout << "\n*** diffProgram returned true!\n";
+        debugMiscompilation();
+        return true;
+      }
+      else{
+        std::cout << "\n*** diff'd output matches!\n";
+      }
+    } catch (ToolExecutionError &TEE) {
+      std::cerr << TEE.what();
+      debugCodeGeneratorCrash();
+      return true;
+    }
+    
+    sys::Path(Filename).eraseFromDisk();
+    
+    std::cout << "\n\n";
+    num++;
+  } //end while
+  
+  // This will never be reached
+  std::cout << "Did not find any bugs :-( \n";
+  return false;                          
+}