1 files changed, 125 insertions, 0 deletions
diff --git a/lib/Transforms/Instrumentation/EmitFunctions.cpp b/lib/Transforms/Instrumentation/EmitFunctions.cpp
new file mode 100644
index 0000000000..a49129399d
--- /dev/null
+++ b/lib/Transforms/Instrumentation/EmitFunctions.cpp
@@ -0,0 +1,125 @@
+//===-- EmitFunctions.cpp - interface to insert instrumentation -----------===//
+//
+//                     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 inserts into the input module three new global constants containing
+// mapping information pertinent to the Reoptimizer's runtime library:
+// 1) a structure containing a pointer to each function;
+// 2) an array containing a boolean which is true iff the corresponding
+//    function in 1) contains a back-edge branch suitable for the Reoptimizer's
+//    first-level instrumentation;
+// 3) an integer containing the number of entries in 1) and 2).
+//
+// NOTE: This pass is used by the reoptimizer only.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/CFG.h"
+#include "llvm/Transforms/Instrumentation.h"
+using namespace llvm;
+
+namespace llvm {
+
+namespace {
+  enum Color{
+    WHITE,
+    GREY,
+    BLACK
+  };
+
+  struct EmitFunctionTable : public ModulePass {
+    bool runOnModule(Module &M);
+  };
+
+  RegisterOpt<EmitFunctionTable>
+  X("emitfuncs", "Emit a function table for the reoptimizer");
+}
+
+static char doDFS(BasicBlock * node,std::map<BasicBlock *, Color > &color){
+  color[node] = GREY;
+
+  for(succ_iterator vl = succ_begin(node), ve = succ_end(node); vl != ve; ++vl){
+
+    BasicBlock *BB = *vl;
+
+    if(color[BB]!=GREY && color[BB]!=BLACK){
+      if(!doDFS(BB, color)){
+        return 0;
+      }
+    }
+
+    //if has backedge
+    else if(color[BB]==GREY)
+      return 0;
+
+  }
+
+  color[node] = BLACK;
+  return 1;
+}
+
+static char hasBackEdge(Function *F){
+  std::map<BasicBlock *, Color > color;
+  return doDFS(F->begin(), color);
+}
+
+// Per Module pass for inserting function table
+bool EmitFunctionTable::runOnModule(Module &M){
+  std::vector<const Type*> vType;
+
+  std::vector<Constant *> vConsts;
+  std::vector<Constant *> sBCons;
+
+  unsigned int counter = 0;
+  for(Module::iterator MI = M.begin(), ME = M.end(); MI != ME; ++MI)
+    if (!MI->isExternal()) {
+      vType.push_back(MI->getType());
+
+      //std::cerr<<MI;
+
+      vConsts.push_back(MI);
+      sBCons.push_back(ConstantInt::get(Type::SByteTy, hasBackEdge(MI)));
+
+      counter++;
+    }
+
+  StructType *sttype = StructType::get(vType);
+  Constant *cstruct = ConstantStruct::get(sttype, vConsts);
+
+  GlobalVariable *gb = new GlobalVariable(cstruct->getType(), true,
+                                          GlobalValue::ExternalLinkage,
+                                          cstruct, "llvmFunctionTable");
+  M.getGlobalList().push_back(gb);
+
+  Constant *constArray = ConstantArray::get(ArrayType::get(Type::SByteTy,
+                                                                sBCons.size()),
+                                                 sBCons);
+
+  GlobalVariable *funcArray = new GlobalVariable(constArray->getType(), true,
+                                              GlobalValue::ExternalLinkage,
+                                              constArray, "llvmSimpleFunction");
+
+  M.getGlobalList().push_back(funcArray);
+
+  ConstantInt *cnst = ConstantSInt::get(Type::IntTy, counter);
+  GlobalVariable *fnCount = new GlobalVariable(Type::IntTy, true,
+                                               GlobalValue::ExternalLinkage,
+                                               cnst, "llvmFunctionCount");
+  M.getGlobalList().push_back(fnCount);
+  return true;  // Always modifies program
+}
+
+ModulePass *createEmitFunctionTablePass () {
+  return new EmitFunctionTable();
+}
+
+} // end namespace llvm