1 files changed, 128 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Transforms/Utils/ModuleUtils.cpp b/contrib/llvm/lib/Transforms/Utils/ModuleUtils.cpp
new file mode 100644
index 000000000000..eb9188518624
--- /dev/null
+++ b/contrib/llvm/lib/Transforms/Utils/ModuleUtils.cpp
@@ -0,0 +1,128 @@
+//===-- ModuleUtils.cpp - Functions to manipulate Modules -----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This family of functions perform manipulations on Modules.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/ModuleUtils.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+static void appendToGlobalArray(const char *Array, Module &M, Function *F,
+                                int Priority, Constant *Data) {
+  IRBuilder<> IRB(M.getContext());
+  FunctionType *FnTy = FunctionType::get(IRB.getVoidTy(), false);
+
+  // Get the current set of static global constructors and add the new ctor
+  // to the list.
+  SmallVector<Constant *, 16> CurrentCtors;
+  StructType *EltTy;
+  if (GlobalVariable *GVCtor = M.getNamedGlobal(Array)) {
+    ArrayType *ATy = cast<ArrayType>(GVCtor->getValueType());
+    StructType *OldEltTy = cast<StructType>(ATy->getElementType());
+    // Upgrade a 2-field global array type to the new 3-field format if needed.
+    if (Data && OldEltTy->getNumElements() < 3)
+      EltTy = StructType::get(IRB.getInt32Ty(), PointerType::getUnqual(FnTy),
+                              IRB.getInt8PtrTy(), nullptr);
+    else
+      EltTy = OldEltTy;
+    if (Constant *Init = GVCtor->getInitializer()) {
+      unsigned n = Init->getNumOperands();
+      CurrentCtors.reserve(n + 1);
+      for (unsigned i = 0; i != n; ++i) {
+        auto Ctor = cast<Constant>(Init->getOperand(i));
+        if (EltTy != OldEltTy)
+          Ctor = ConstantStruct::get(
+              EltTy, Ctor->getAggregateElement((unsigned)0),
+              Ctor->getAggregateElement(1),
+              Constant::getNullValue(IRB.getInt8PtrTy()), nullptr);
+        CurrentCtors.push_back(Ctor);
+      }
+    }
+    GVCtor->eraseFromParent();
+  } else {
+    // Use the new three-field struct if there isn't one already.
+    EltTy = StructType::get(IRB.getInt32Ty(), PointerType::getUnqual(FnTy),
+                            IRB.getInt8PtrTy(), nullptr);
+  }
+
+  // Build a 2 or 3 field global_ctor entry.  We don't take a comdat key.
+  Constant *CSVals[3];
+  CSVals[0] = IRB.getInt32(Priority);
+  CSVals[1] = F;
+  // FIXME: Drop support for the two element form in LLVM 4.0.
+  if (EltTy->getNumElements() >= 3)
+    CSVals[2] = Data ? ConstantExpr::getPointerCast(Data, IRB.getInt8PtrTy())
+                     : Constant::getNullValue(IRB.getInt8PtrTy());
+  Constant *RuntimeCtorInit =
+      ConstantStruct::get(EltTy, makeArrayRef(CSVals, EltTy->getNumElements()));
+
+  CurrentCtors.push_back(RuntimeCtorInit);
+
+  // Create a new initializer.
+  ArrayType *AT = ArrayType::get(EltTy, CurrentCtors.size());
+  Constant *NewInit = ConstantArray::get(AT, CurrentCtors);
+
+  // Create the new global variable and replace all uses of
+  // the old global variable with the new one.
+  (void)new GlobalVariable(M, NewInit->getType(), false,
+                           GlobalValue::AppendingLinkage, NewInit, Array);
+}
+
+void llvm::appendToGlobalCtors(Module &M, Function *F, int Priority, Constant *Data) {
+  appendToGlobalArray("llvm.global_ctors", M, F, Priority, Data);
+}
+
+void llvm::appendToGlobalDtors(Module &M, Function *F, int Priority, Constant *Data) {
+  appendToGlobalArray("llvm.global_dtors", M, F, Priority, Data);
+}
+
+Function *llvm::checkSanitizerInterfaceFunction(Constant *FuncOrBitcast) {
+  if (isa<Function>(FuncOrBitcast))
+    return cast<Function>(FuncOrBitcast);
+  FuncOrBitcast->dump();
+  std::string Err;
+  raw_string_ostream Stream(Err);
+  Stream << "Sanitizer interface function redefined: " << *FuncOrBitcast;
+  report_fatal_error(Err);
+}
+
+std::pair<Function *, Function *> llvm::createSanitizerCtorAndInitFunctions(
+    Module &M, StringRef CtorName, StringRef InitName,
+    ArrayRef<Type *> InitArgTypes, ArrayRef<Value *> InitArgs,
+    StringRef VersionCheckName) {
+  assert(!InitName.empty() && "Expected init function name");
+  assert(InitArgTypes.size() == InitArgTypes.size() &&
+         "Sanitizer's init function expects different number of arguments");
+  Function *Ctor = Function::Create(
+      FunctionType::get(Type::getVoidTy(M.getContext()), false),
+      GlobalValue::InternalLinkage, CtorName, &M);
+  BasicBlock *CtorBB = BasicBlock::Create(M.getContext(), "", Ctor);
+  IRBuilder<> IRB(ReturnInst::Create(M.getContext(), CtorBB));
+  Function *InitFunction =
+      checkSanitizerInterfaceFunction(M.getOrInsertFunction(
+          InitName, FunctionType::get(IRB.getVoidTy(), InitArgTypes, false),
+          AttributeSet()));
+  InitFunction->setLinkage(Function::ExternalLinkage);
+  IRB.CreateCall(InitFunction, InitArgs);
+  if (!VersionCheckName.empty()) {
+    Function *VersionCheckFunction =
+        checkSanitizerInterfaceFunction(M.getOrInsertFunction(
+            VersionCheckName, FunctionType::get(IRB.getVoidTy(), {}, false),
+            AttributeSet()));
+    IRB.CreateCall(VersionCheckFunction, {});
+  }
+  return std::make_pair(Ctor, InitFunction);
+}