+/// \brief Replaces llvm.dbg.declare instruction when an alloca is replaced with
+/// a new value. If Deref is true, tan additional DW_OP_deref is prepended to
+/// the expression.
+bool replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
+ DIBuilder &Builder, bool Deref);
+
+/// Replace 'BB's terminator with one that does not have an unwind successor
+/// block. Rewrites `invoke` to `call`, `catchendpad unwind label %foo` to
+/// `catchendpad unwind to caller`, etc. Updates any PHIs in unwind successor.
+///
+/// \param BB Block whose terminator will be replaced. Its terminator must
+/// have an unwind successor.
+void removeUnwindEdge(BasicBlock *BB);
+
+/// \brief Remove all blocks that can not be reached from the function's entry.
+///
+/// Returns true if any basic block was removed.
+bool removeUnreachableBlocks(Function &F);
+
+/// \brief Combine the metadata of two instructions so that K can replace J
+///
+/// Metadata not listed as known via KnownIDs is removed
+void combineMetadata(Instruction *K, const Instruction *J, ArrayRef<unsigned> KnownIDs);
+
+/// \brief Replace each use of 'From' with 'To' if that use is dominated by
+/// the given edge. Returns the number of replacements made.
+unsigned replaceDominatedUsesWith(Value *From, Value *To, DominatorTree &DT,
+ const BasicBlockEdge &Edge);
+/// \brief Replace each use of 'From' with 'To' if that use is dominated by
+/// the given BasicBlock. Returns the number of replacements made.
+unsigned replaceDominatedUsesWith(Value *From, Value *To, DominatorTree &DT,
+ const BasicBlock *BB);