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diff --git a/lib/Transforms/Instrumentation/BlockProfiling.cpp b/lib/Transforms/Instrumentation/BlockProfiling.cpp
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index 0000000000..f92f0ef6f0
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+++ b/lib/Transforms/Instrumentation/BlockProfiling.cpp
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+//===- BlockProfiling.cpp - Insert counters for block profiling -----------===//
+//
+//                      The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass instruments the specified program with counters for basic block or
+// function profiling.  This is the most basic form of profiling, which can tell
+// which blocks are hot, but cannot reliably detect hot paths through the CFG.
+// Block profiling counts the number of times each basic block executes, and
+// function profiling counts the number of times each function is called.
+//
+// Note that this implementation is very naive.  Control equivalent regions of
+// the CFG should not require duplicate counters, but we do put duplicate
+// counters in.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Transforms/Instrumentation.h"
+#include "ProfilingUtils.h"
+#include <iostream>
+
+using namespace llvm;
+
+namespace {
+  class FunctionProfiler : public ModulePass {
+    bool runOnModule(Module &M);
+  };
+
+  RegisterOpt<FunctionProfiler> X("insert-function-profiling",
+                               "Insert instrumentation for function profiling");
+}
+
+ModulePass *llvm::createFunctionProfilerPass() {
+  return new FunctionProfiler();
+}
+
+bool FunctionProfiler::runOnModule(Module &M) {
+  Function *Main = M.getMainFunction();
+  if (Main == 0) {
+    std::cerr << "WARNING: cannot insert function profiling into a module"
+              << " with no main function!\n";
+    return false;  // No main, no instrumentation!
+  }
+
+  unsigned NumFunctions = 0;
+  for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
+    if (!I->isExternal())
+      ++NumFunctions;
+
+  const Type *ATy = ArrayType::get(Type::UIntTy, NumFunctions);
+  GlobalVariable *Counters =
+    new GlobalVariable(ATy, false, GlobalValue::InternalLinkage,
+                       Constant::getNullValue(ATy), "FuncProfCounters", &M);
+
+  // Instrument all of the functions...
+  unsigned i = 0;
+  for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
+    if (!I->isExternal())
+      // Insert counter at the start of the function
+      IncrementCounterInBlock(I->begin(), i++, Counters);
+
+  // Add the initialization call to main.
+  InsertProfilingInitCall(Main, "llvm_start_func_profiling", Counters);
+  return true;
+}
+
+
+namespace {
+  class BlockProfiler : public ModulePass {
+    bool runOnModule(Module &M);
+  };
+
+  RegisterOpt<BlockProfiler> Y("insert-block-profiling",
+                               "Insert instrumentation for block profiling");
+}
+
+ModulePass *llvm::createBlockProfilerPass() { return new BlockProfiler(); }
+
+bool BlockProfiler::runOnModule(Module &M) {
+  Function *Main = M.getMainFunction();
+  if (Main == 0) {
+    std::cerr << "WARNING: cannot insert block profiling into a module"
+              << " with no main function!\n";
+    return false;  // No main, no instrumentation!
+  }
+
+  unsigned NumBlocks = 0;
+  for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
+    NumBlocks += I->size();
+
+  const Type *ATy = ArrayType::get(Type::UIntTy, NumBlocks);
+  GlobalVariable *Counters =
+    new GlobalVariable(ATy, false, GlobalValue::InternalLinkage,
+                       Constant::getNullValue(ATy), "BlockProfCounters", &M);
+
+  // Instrument all of the blocks...
+  unsigned i = 0;
+  for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
+    for (Function::iterator BB = I->begin(), E = I->end(); BB != E; ++BB)
+      // Insert counter at the start of the block
+      IncrementCounterInBlock(BB, i++, Counters);
+
+  // Add the initialization call to main.
+  InsertProfilingInitCall(Main, "llvm_start_block_profiling", Counters);
+  return true;
+}
+