//===-- User.cpp - Implement the User class -------------------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #include "llvm/IR/User.h" #include "llvm/IR/Constant.h" #include "llvm/IR/GlobalValue.h" #include "llvm/IR/Operator.h" namespace llvm { //===----------------------------------------------------------------------===// // User Class //===----------------------------------------------------------------------===// void User::anchor() {} // replaceUsesOfWith - Replaces all references to the "From" definition with // references to the "To" definition. // void User::replaceUsesOfWith(Value *From, Value *To) { if (From == To) return; // Duh what? assert((!isa<Constant>(this) || isa<GlobalValue>(this)) && "Cannot call User::replaceUsesOfWith on a constant!"); for (unsigned i = 0, E = getNumOperands(); i != E; ++i) if (getOperand(i) == From) { // Is This operand is pointing to oldval? // The side effects of this setOperand call include linking to // "To", adding "this" to the uses list of To, and // most importantly, removing "this" from the use list of "From". setOperand(i, To); // Fix it now... } } //===----------------------------------------------------------------------===// // User allocHungoffUses Implementation //===----------------------------------------------------------------------===// Use *User::allocHungoffUses(unsigned N) const { // Allocate the array of Uses, followed by a pointer (with bottom bit set) to // the User. size_t size = N * sizeof(Use) + sizeof(Use::UserRef); Use *Begin = static_cast<Use*>(::operator new(size)); Use *End = Begin + N; (void) new(End) Use::UserRef(const_cast<User*>(this), 1); return Use::initTags(Begin, End); } //===----------------------------------------------------------------------===// // User operator new Implementations //===----------------------------------------------------------------------===// void *User::operator new(size_t s, unsigned Us) { void *Storage = ::operator new(s + sizeof(Use) * Us); Use *Start = static_cast<Use*>(Storage); Use *End = Start + Us; User *Obj = reinterpret_cast<User*>(End); Obj->OperandList = Start; Obj->NumOperands = Us; Use::initTags(Start, End); return Obj; } //===----------------------------------------------------------------------===// // User operator delete Implementation //===----------------------------------------------------------------------===// void User::operator delete(void *Usr) { User *Start = static_cast<User*>(Usr); Use *Storage = static_cast<Use*>(Usr) - Start->NumOperands; // If there were hung-off uses, they will have been freed already and // NumOperands reset to 0, so here we just free the User itself. ::operator delete(Storage); } //===----------------------------------------------------------------------===// // Operator Class //===----------------------------------------------------------------------===// Operator::~Operator() { llvm_unreachable("should never destroy an Operator"); } } // End llvm namespace