Rebased PNaCl localmods in LLVM to 223109

lib/Transforms/NaCl/ExpandUtils.cpp

Index: lib/Transforms/NaCl/ExpandUtils.cpp
diff --git a/lib/Transforms/NaCl/ExpandUtils.cpp b/lib/Transforms/NaCl/ExpandUtils.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..f825f3fce3bd06819ddacca8150d6d42df3676b0
--- /dev/null
+++ b/lib/Transforms/NaCl/ExpandUtils.cpp
@@ -0,0 +1,58 @@
+//===-- ExpandUtils.cpp - Helper functions for expansion passes -----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/NaCl.h"
+
+using namespace llvm;
+
+Instruction *llvm::PhiSafeInsertPt(Use *U) {
+  Instruction *InsertPt = cast<Instruction>(U->getUser());
+  if (PHINode *PN = dyn_cast<PHINode>(InsertPt)) {
+    // We cannot insert instructions before a PHI node, so insert
+    // before the incoming block's terminator.  This could be
+    // suboptimal if the terminator is a conditional.
+    InsertPt = PN->getIncomingBlock(*U)->getTerminator();
+  }
+  return InsertPt;
+}
+
+void llvm::PhiSafeReplaceUses(Use *U, Value *NewVal) {
+  User *UR = U->getUser();
+  if (PHINode *PN = dyn_cast<PHINode>(UR)) {
+    // A PHI node can have multiple incoming edges from the same
+    // block, in which case all these edges must have the same
+    // incoming value.
+    BasicBlock *BB = PN->getIncomingBlock(*U);
+    for (unsigned I = 0; I < PN->getNumIncomingValues(); ++I) {
+      if (PN->getIncomingBlock(I) == BB)
+        PN->setIncomingValue(I, NewVal);
+    }
+  } else {
+    UR->replaceUsesOfWith(U->get(), NewVal);
+  }
+}
+
+Function *llvm::RecreateFunction(Function *Func, FunctionType *NewType) {
+  Function *NewFunc = Function::Create(NewType, Func->getLinkage());
+  NewFunc->copyAttributesFrom(Func);
+  Func->getParent()->getFunctionList().insert(Func, NewFunc);
+  NewFunc->takeName(Func);
+  NewFunc->getBasicBlockList().splice(NewFunc->begin(),
+                                      Func->getBasicBlockList());
+  Func->replaceAllUsesWith(
+      ConstantExpr::getBitCast(NewFunc,
+                               Func->getFunctionType()->getPointerTo()));
+  return NewFunc;
+}