1 //===-- User.cpp - Implement the User class -------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "llvm/IR/User.h" 11 #include "llvm/IR/Constant.h" 12 #include "llvm/IR/GlobalValue.h" 13 #include "llvm/IR/Operator.h" 14 15 namespace llvm { 16 17 //===----------------------------------------------------------------------===// 18 // User Class 19 //===----------------------------------------------------------------------===// 20 21 void User::anchor() {} 22 23 void User::replaceUsesOfWith(Value *From, Value *To) { 24 if (From == To) return; // Duh what? 25 26 assert((!isa<Constant>(this) || isa<GlobalValue>(this)) && 27 "Cannot call User::replaceUsesOfWith on a constant!"); 28 29 for (unsigned i = 0, E = getNumOperands(); i != E; ++i) 30 if (getOperand(i) == From) { // Is This operand is pointing to oldval? 31 // The side effects of this setOperand call include linking to 32 // "To", adding "this" to the uses list of To, and 33 // most importantly, removing "this" from the use list of "From". 34 setOperand(i, To); // Fix it now... 35 } 36 } 37 38 //===----------------------------------------------------------------------===// 39 // User allocHungoffUses Implementation 40 //===----------------------------------------------------------------------===// 41 42 Use *User::allocHungoffUses(unsigned N) const { 43 // Allocate the array of Uses, followed by a pointer (with bottom bit set) to 44 // the User. 45 size_t size = N * sizeof(Use) + sizeof(Use::UserRef); 46 Use *Begin = static_cast<Use*>(::operator new(size)); 47 Use *End = Begin + N; 48 (void) new(End) Use::UserRef(const_cast<User*>(this), 1); 49 return Use::initTags(Begin, End); 50 } 51 52 //===----------------------------------------------------------------------===// 53 // User operator new Implementations 54 //===----------------------------------------------------------------------===// 55 56 void *User::operator new(size_t s, unsigned Us) { 57 void *Storage = ::operator new(s + sizeof(Use) * Us); 58 Use *Start = static_cast<Use*>(Storage); 59 Use *End = Start + Us; 60 User *Obj = reinterpret_cast<User*>(End); 61 Obj->OperandList = Start; 62 Obj->NumOperands = Us; 63 Use::initTags(Start, End); 64 return Obj; 65 } 66 67 //===----------------------------------------------------------------------===// 68 // User operator delete Implementation 69 //===----------------------------------------------------------------------===// 70 71 void User::operator delete(void *Usr) { 72 User *Start = static_cast<User*>(Usr); 73 Use *Storage = static_cast<Use*>(Usr) - Start->NumOperands; 74 // If there were hung-off uses, they will have been freed already and 75 // NumOperands reset to 0, so here we just free the User itself. 76 ::operator delete(Storage); 77 } 78 79 //===----------------------------------------------------------------------===// 80 // Operator Class 81 //===----------------------------------------------------------------------===// 82 83 Operator::~Operator() { 84 llvm_unreachable("should never destroy an Operator"); 85 } 86 87 } // End llvm namespace 88
