lib/VMCore/Instruction.cpp

   1 //===-- Instruction.cpp - Implement the Instruction class -----------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file was developed by the LLVM research group and is distributed under
   6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the Instruction class for the VMCore library.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Instructions.h"
  15 #include "llvm/Function.h"
  16 #include "llvm/SymbolTable.h"
  17 #include "llvm/Type.h"
  18 #include "llvm/Support/LeakDetector.h"
  19 using namespace llvm;
  20
  21 Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
  22                          const std::string &Name, Instruction *InsertBefore)
  23   : User(ty, Value::InstructionVal + it, Ops, NumOps, Name), Parent(0) {
  24   // Make sure that we get added to a basicblock
  25   LeakDetector::addGarbageObject(this);
  26
  27   // If requested, insert this instruction into a basic block...
  28   if (InsertBefore) {
  29     assert(InsertBefore->getParent() &&
  30            "Instruction to insert before is not in a basic block!");
  31     InsertBefore->getParent()->getInstList().insert(InsertBefore, this);
  32   }
  33 }
  34
  35 Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
  36                          const std::string &Name, BasicBlock *InsertAtEnd)
  37   : User(ty, Value::InstructionVal + it, Ops, NumOps, Name), Parent(0) {
  38   // Make sure that we get added to a basicblock
  39   LeakDetector::addGarbageObject(this);
  40
  41   // append this instruction into the basic block
  42   assert(InsertAtEnd && "Basic block to append to may not be NULL!");
  43   InsertAtEnd->getInstList().push_back(this);
  44 }
  45
  46 // Out of line virtual method, so the vtable, etc has a home.
  47 Instruction::~Instruction() {
  48   assert(Parent == 0 && "Instruction still linked in the program!");
  49 }
  50
  51
  52 void Instruction::setOpcode(unsigned opc) {
  53   setValueType(Value::InstructionVal + opc);
  54 }
  55
  56 void Instruction::setParent(BasicBlock *P) {
  57   if (getParent()) {
  58     if (!P) LeakDetector::addGarbageObject(this);
  59   } else {
  60     if (P) LeakDetector::removeGarbageObject(this);
  61   }
  62
  63   Parent = P;
  64 }
  65
  66 void Instruction::removeFromParent() {
  67   getParent()->getInstList().remove(this);
  68 }
  69
  70 void Instruction::eraseFromParent() {
  71   getParent()->getInstList().erase(this);
  72 }
  73
  74 /// moveBefore - Unlink this instruction from its current basic block and
  75 /// insert it into the basic block that MovePos lives in, right before
  76 /// MovePos.
  77 void Instruction::moveBefore(Instruction *MovePos) {
  78   MovePos->getParent()->getInstList().splice(MovePos,getParent()->getInstList(),
  79                                              this);
  80 }
  81
  82
  83 const char *Instruction::getOpcodeName(unsigned OpCode) {
  84   switch (OpCode) {
  85   // Terminators
  86   case Ret:    return "ret";
  87   case Br:     return "br";
  88   case Switch: return "switch";
  89   case Invoke: return "invoke";
  90   case Unwind: return "unwind";
  91   case Unreachable: return "unreachable";
  92
  93   // Standard binary operators...
  94   case Add: return "add";
  95   case Sub: return "sub";
  96   case Mul: return "mul";
  97   case Div: return "div";
  98   case Rem: return "rem";
  99
 100   // Logical operators...
 101   case And: return "and";
 102   case Or : return "or";
 103   case Xor: return "xor";
 104
 105   // SetCC operators...
 106   case SetLE:  return "setle";
 107   case SetGE:  return "setge";
 108   case SetLT:  return "setlt";
 109   case SetGT:  return "setgt";
 110   case SetEQ:  return "seteq";
 111   case SetNE:  return "setne";
 112
 113   // Memory instructions...
 114   case Malloc:        return "malloc";
 115   case Free:          return "free";
 116   case Alloca:        return "alloca";
 117   case Load:          return "load";
 118   case Store:         return "store";
 119   case GetElementPtr: return "getelementptr";
 120
 121   // Other instructions...
 122   case PHI:     return "phi";
 123   case Cast:    return "cast";
 124   case Select:  return "select";
 125   case Call:    return "call";
 126   case Shl:     return "shl";
 127   case Shr:     return "shr";
 128   case VAArg:   return "va_arg";
 129   case ExtractElement: return "extractelement";
 130   case InsertElement: return "insertelement";
 131   case ShuffleVector: return "shufflevector";
 132
 133   default: return "<Invalid operator> ";
 134   }
 135
 136   return 0;
 137 }
 138
 139 /// isIdenticalTo - Return true if the specified instruction is exactly
 140 /// identical to the current one.  This means that all operands match and any
 141 /// extra information (e.g. load is volatile) agree.
 142 bool Instruction::isIdenticalTo(Instruction *I) const {
 143   if (getOpcode() != I->getOpcode() ||
 144       getNumOperands() != I->getNumOperands() ||
 145       getType() != I->getType())
 146     return false;
 147
 148   // We have two instructions of identical opcode and #operands.  Check to see
 149   // if all operands are the same.
 150   for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
 151     if (getOperand(i) != I->getOperand(i))
 152       return false;
 153
 154   // Check special state that is a part of some instructions.
 155   if (const LoadInst *LI = dyn_cast<LoadInst>(this))
 156     return LI->isVolatile() == cast<LoadInst>(I)->isVolatile();
 157   if (const StoreInst *SI = dyn_cast<StoreInst>(this))
 158     return SI->isVolatile() == cast<StoreInst>(I)->isVolatile();
 159   if (const CallInst *CI = dyn_cast<CallInst>(this))
 160     return CI->isTailCall() == cast<CallInst>(I)->isTailCall();
 161   return true;
 162 }
 163
 164
 165 /// isAssociative - Return true if the instruction is associative:
 166 ///
 167 ///   Associative operators satisfy:  x op (y op z) === (x op y) op z)
 168 ///
 169 /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative, when not
 170 /// applied to floating point types.
 171 ///
 172 bool Instruction::isAssociative(unsigned Opcode, const Type *Ty) {
 173   if (Opcode == Add || Opcode == Mul ||
 174       Opcode == And || Opcode == Or || Opcode == Xor) {
 175     // Floating point operations do not associate!
 176     return !Ty->isFloatingPoint();
 177   }
 178   return 0;
 179 }
 180
 181 /// isCommutative - Return true if the instruction is commutative:
 182 ///
 183 ///   Commutative operators satisfy: (x op y) === (y op x)
 184 ///
 185 /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
 186 /// applied to any type.
 187 ///
 188 bool Instruction::isCommutative(unsigned op) {
 189   switch (op) {
 190   case Add:
 191   case Mul:
 192   case And:
 193   case Or:
 194   case Xor:
 195   case SetEQ:
 196   case SetNE:
 197     return true;
 198   default:
 199     return false;
 200   }
 201 }
 202
 203 /// isRelational - Return true if the instruction is a Set* instruction:
 204 ///
 205 bool Instruction::isRelational(unsigned op) {
 206   switch (op) {
 207   case SetEQ:
 208   case SetNE:
 209   case SetLT:
 210   case SetGT:
 211   case SetLE:
 212   case SetGE:
 213     return true;
 214   }
 215   return false;
 216 }
 217
 218
 219
 220 /// isTrappingInstruction - Return true if the instruction may trap.
 221 ///
 222 bool Instruction::isTrapping(unsigned op) {
 223   switch(op) {
 224   case Div:
 225   case Rem:
 226   case Load:
 227   case Store:
 228   case Call:
 229   case Invoke:
 230     return true;
 231   default:
 232     return false;
 233   }
 234 }