3 files changed, 98 insertions, 1 deletions
diff --git a/include/llvm/Transforms/IPO.h b/include/llvm/Transforms/IPO.h
index ca5959ce4b..eba40b8516 100644
--- a/include/llvm/Transforms/IPO.h
+++ b/include/llvm/Transforms/IPO.h
@@ -169,6 +169,11 @@ ModulePass *createBlockExtractorPass(std::vector<BasicBlock*> &BTNE);
 // specific well-known (library) functions.
 ModulePass *createSimplifyLibCallsPass();
 
+
+// createIndMemRemPass - This pass removes potential indirect calls of
+// malloc and free
+ModulePass *createIndMemRemPass();
+
 } // End llvm namespace
 
 #endif
diff --git a/include/llvm/Transforms/LinkAllPasses.h b/include/llvm/Transforms/LinkAllPasses.h
index cc9621fefa..ac64f855ec 100644
--- a/include/llvm/Transforms/LinkAllPasses.h
+++ b/include/llvm/Transforms/LinkAllPasses.h
@@ -107,7 +107,7 @@ namespace {
       (void) llvm::createCondPropagationPass();
       (void) llvm::createNullProfilerRSPass();
       (void) llvm::createRSProfilingPass();
-
+      (void) llvm::createIndMemRemPass();
     }
   } ForcePassLinking;
 }
diff --git a/lib/Transforms/IPO/IndMemRemoval.cpp b/lib/Transforms/IPO/IndMemRemoval.cpp
new file mode 100644
index 0000000000..84a4307228
--- /dev/null
+++ b/lib/Transforms/IPO/IndMemRemoval.cpp
@@ -0,0 +1,92 @@
+//===-- IndMemRemoval.cpp - Remove indirect allocations and frees ----------===//
+//
+//                     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 finds places where memory allocation functions may escape into
+// indirect land.  Some transforms are much easier (aka possible) only if free 
+// or malloc are not called indirectly.
+// Thus find places where the address of memory functions are taken and construct
+// bounce functions with direct calls of those functions.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Pass.h"
+#include "llvm/Module.h"
+#include "llvm/Function.h"
+#include "llvm/Instructions.h"
+#include "llvm/Type.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/ADT/Statistic.h"
+#include <fstream>
+#include <iostream>
+#include <set>
+using namespace llvm;
+
+namespace {
+  Statistic<> NumBounceSites("indmemrem", "Number of sites modified");
+  Statistic<> NumBounce  ("indmemrem", "Number of bounce functions created");
+
+  class IndMemRemPass : public ModulePass {
+
+  public:
+    IndMemRemPass();
+    virtual bool runOnModule(Module &M);
+  };
+  RegisterOpt<IndMemRemPass> X("indmemrem", "Indirect Malloc and Free Removal");
+} // end anonymous namespace
+
+
+IndMemRemPass::IndMemRemPass()
+{
+}
+
+bool IndMemRemPass::runOnModule(Module &M) {
+  //in Theory, all direct calls of malloc and free should be promoted
+  //to intrinsics.  Therefor, this goes through and finds where the
+  //address of free or malloc are taken and replaces those with bounce
+  //functions, ensuring that all malloc and free that might happen
+  //happens through intrinsics.
+  bool changed = false;
+  if (Function* F = M.getNamedFunction("free")) {
+    assert(F->isExternal() && "free not external?");
+    if (F->getNumUses()) {
+      Function* FN = new Function(F->getFunctionType(), 
+				  GlobalValue::LinkOnceLinkage, 
+				  "free_llvm_bounce", &M);
+      BasicBlock* bb = new BasicBlock("entry",FN);
+      Instruction* R = new ReturnInst(bb);
+      new FreeInst(FN->arg_begin(), R);
+      ++NumBounce;
+      NumBounceSites += F->getNumUses();
+      F->replaceAllUsesWith(FN);
+      changed = true;
+    }
+  }
+  if (Function* F = M.getNamedFunction("malloc")) {
+    assert(F->isExternal() && "malloc not external?");
+    if (F->getNumUses()) {
+      Function* FN = new Function(F->getFunctionType(), 
+				  GlobalValue::LinkOnceLinkage, 
+				  "malloc_llvm_bounce", &M);
+      BasicBlock* bb = new BasicBlock("entry",FN);
+      Instruction* c = new CastInst(FN->arg_begin(), Type::UIntTy, "c", bb);
+      Instruction* a = new MallocInst(Type::SByteTy, c, "m", bb);
+      Instruction* R = new ReturnInst(a, bb);
+      ++NumBounce;
+      NumBounceSites += F->getNumUses();
+      F->replaceAllUsesWith(FN);
+      changed = true;
+    }
+  }
+  return changed;
+}
+
+ModulePass *llvm::createIndMemRemPass() {
+  return new IndMemRemPass();
+}