Initial KLEE checkin.

 - Lots more tweaks, documentation, and web page content is needed,
   but this should compile & work on OS X & Linux.


git-svn-id: https://llvm.org/svn/llvm-project/klee/trunk@72205 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 101 insertions, 0 deletions

diff --git a/lib/Module/ModuleUtil.cpp b/lib/Module/ModuleUtil.cpp
new file mode 100644
index 00000000..d86b9d48
--- /dev/null
+++ b/lib/Module/ModuleUtil.cpp
@@ -0,0 +1,101 @@
+//===-- ModuleUtil.cpp ----------------------------------------------------===//
+//
+//                     The KLEE Symbolic Virtual Machine
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "klee/Internal/Support/ModuleUtil.h"
+
+#include "llvm/Function.h"
+#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/Linker.h"
+#include "llvm/Module.h"
+#include "llvm/Assembly/AsmAnnotationWriter.h"
+#include "llvm/Support/CFG.h"
+#include "llvm/Support/InstIterator.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Analysis/ValueTracking.h"
+
+#include <map>
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <string>
+
+using namespace llvm;
+using namespace klee;
+
+Module *klee::linkWithLibrary(Module *module, 
+                              const std::string &libraryName) {
+  try {
+    Linker linker("klee", module, false);
+
+    llvm::sys::Path libraryPath(libraryName);
+    bool native = false;
+    
+    if (linker.LinkInFile(libraryPath, native)) {
+      assert(0 && "linking in library failed!");
+    }
+    
+    return linker.releaseModule();
+  } catch (...) {
+    assert(0 && "error during linking");
+  }
+}
+
+Function *klee::getDirectCallTarget(const Instruction *i) {
+  assert(isa<CallInst>(i) || isa<InvokeInst>(i));
+
+  Value *v = i->getOperand(0);
+  if (Function *f = dyn_cast<Function>(v)) {
+    return f;
+  } else if (llvm::ConstantExpr *ce = dyn_cast<llvm::ConstantExpr>(v)) {
+    if (ce->getOpcode()==Instruction::BitCast)
+      if (Function *f = dyn_cast<Function>(ce->getOperand(0)))
+        return f;
+
+    // NOTE: This assert may fire, it isn't necessarily a problem and
+    // can be disabled, I just wanted to know when and if it happened.
+    assert(0 && "FIXME: Unresolved direct target for a constant expression.");
+  }
+  
+  return 0;
+}
+
+static bool valueIsOnlyCalled(const Value *v) {
+  for (Value::use_const_iterator it = v->use_begin(), ie = v->use_end();
+       it != ie; ++it) {
+    if (const Instruction *instr = dyn_cast<Instruction>(*it)) {
+      if (instr->getOpcode()==0) continue; // XXX function numbering inst
+      if (!isa<CallInst>(instr) && !isa<InvokeInst>(instr)) return false;
+      
+      // Make sure that the value is only the target of this call and
+      // not an argument.
+      for (unsigned i=1,e=instr->getNumOperands(); i!=e; ++i)
+        if (instr->getOperand(i)==v)
+          return false;
+    } else if (const llvm::ConstantExpr *ce = 
+               dyn_cast<llvm::ConstantExpr>(*it)) {
+      if (ce->getOpcode()==Instruction::BitCast)
+        if (valueIsOnlyCalled(ce))
+          continue;
+      return false;
+    } else if (const GlobalAlias *ga = dyn_cast<GlobalAlias>(*it)) {
+      // XXX what about v is bitcast of aliasee?
+      if (v==ga->getAliasee() && !valueIsOnlyCalled(ga))
+        return false;
+    } else {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+bool klee::functionEscapes(const Function *f) {
+  return !valueIsOnlyCalled(f);
+}