1 //===-- llvm/Support/CallSite.h - Abstract Call & Invoke instrs -*- C++ -*-===// 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 // This file defines the CallSite class, which is a handy wrapper for code that 11 // wants to treat Call and Invoke instructions in a generic way. When in non- 12 // mutation context (e.g. an analysis) ImmutableCallSite should be used. 13 // Finally, when some degree of customization is necessary between these two 14 // extremes, CallSiteBase<> can be supplied with fine-tuned parameters. 15 // 16 // NOTE: These classes are supposed to have "value semantics". So they should be 17 // passed by value, not by reference; they should not be "new"ed or "delete"d. 18 // They are efficiently copyable, assignable and constructable, with cost 19 // equivalent to copying a pointer (notice that they have only a single data 20 // member). The internal representation carries a flag which indicates which of 21 // the two variants is enclosed. This allows for cheaper checks when various 22 // accessors of CallSite are employed. 23 // 24 //===----------------------------------------------------------------------===// 25 26 #ifndef LLVM_SUPPORT_CALLSITE_H 27 #define LLVM_SUPPORT_CALLSITE_H 28 29 #include "llvm/ADT/PointerIntPair.h" 30 #include "llvm/IR/Attributes.h" 31 #include "llvm/IR/BasicBlock.h" 32 #include "llvm/IR/CallingConv.h" 33 #include "llvm/IR/Instructions.h" 34 35 namespace llvm { 36 37 class CallInst; 38 class InvokeInst; 39 40 template <typename FunTy = const Function, 41 typename ValTy = const Value, 42 typename UserTy = const User, 43 typename InstrTy = const Instruction, 44 typename CallTy = const CallInst, 45 typename InvokeTy = const InvokeInst, 46 typename IterTy = User::const_op_iterator> 47 class CallSiteBase { 48 protected: 49 PointerIntPair<InstrTy*, 1, bool> I; 50 public: 51 CallSiteBase() : I(0, false) {} 52 CallSiteBase(CallTy *CI) : I(CI, true) { assert(CI); } 53 CallSiteBase(InvokeTy *II) : I(II, false) { assert(II); } 54 CallSiteBase(ValTy *II) { *this = get(II); } 55 protected: 56 /// CallSiteBase::get - This static method is sort of like a constructor. It 57 /// will create an appropriate call site for a Call or Invoke instruction, but 58 /// it can also create a null initialized CallSiteBase object for something 59 /// which is NOT a call site. 60 /// 61 static CallSiteBase get(ValTy *V) { 62 if (InstrTy *II = dyn_cast<InstrTy>(V)) { 63 if (II->getOpcode() == Instruction::Call) 64 return CallSiteBase(static_cast<CallTy*>(II)); 65 else if (II->getOpcode() == Instruction::Invoke) 66 return CallSiteBase(static_cast<InvokeTy*>(II)); 67 } 68 return CallSiteBase(); 69 } 70 public: 71 /// isCall - true if a CallInst is enclosed. 72 /// Note that !isCall() does not mean it is an InvokeInst enclosed, 73 /// it also could signify a NULL Instruction pointer. 74 bool isCall() const { return I.getInt(); } 75 76 /// isInvoke - true if a InvokeInst is enclosed. 77 /// 78 bool isInvoke() const { return getInstruction() && !I.getInt(); } 79 80 InstrTy *getInstruction() const { return I.getPointer(); } 81 InstrTy *operator->() const { return I.getPointer(); } 82 operator bool() const { return I.getPointer(); } 83 84 /// getCalledValue - Return the pointer to function that is being called. 85 /// 86 ValTy *getCalledValue() const { 87 assert(getInstruction() && "Not a call or invoke instruction!"); 88 return *getCallee(); 89 } 90 91 /// getCalledFunction - Return the function being called if this is a direct 92 /// call, otherwise return null (if it's an indirect call). 93 /// 94 FunTy *getCalledFunction() const { 95 return dyn_cast<FunTy>(getCalledValue()); 96 } 97 98 /// setCalledFunction - Set the callee to the specified value. 99 /// 100 void setCalledFunction(Value *V) { 101 assert(getInstruction() && "Not a call or invoke instruction!"); 102 *getCallee() = V; 103 } 104 105 /// isCallee - Determine whether the passed iterator points to the 106 /// callee operand's Use. 107 /// 108 bool isCallee(value_use_iterator<UserTy> UI) const { 109 return getCallee() == &UI.getUse(); 110 } 111 112 ValTy *getArgument(unsigned ArgNo) const { 113 assert(arg_begin() + ArgNo < arg_end() && "Argument # out of range!"); 114 return *(arg_begin() + ArgNo); 115 } 116 117 void setArgument(unsigned ArgNo, Value* newVal) { 118 assert(getInstruction() && "Not a call or invoke instruction!"); 119 assert(arg_begin() + ArgNo < arg_end() && "Argument # out of range!"); 120 getInstruction()->setOperand(ArgNo, newVal); 121 } 122 123 /// Given a value use iterator, returns the argument that corresponds to it. 124 /// Iterator must actually correspond to an argument. 125 unsigned getArgumentNo(value_use_iterator<UserTy> I) const { 126 assert(getInstruction() && "Not a call or invoke instruction!"); 127 assert(arg_begin() <= &I.getUse() && &I.getUse() < arg_end() 128 && "Argument # out of range!"); 129 return &I.getUse() - arg_begin(); 130 } 131 132 /// arg_iterator - The type of iterator to use when looping over actual 133 /// arguments at this call site. 134 typedef IterTy arg_iterator; 135 136 /// arg_begin/arg_end - Return iterators corresponding to the actual argument 137 /// list for a call site. 138 IterTy arg_begin() const { 139 assert(getInstruction() && "Not a call or invoke instruction!"); 140 // Skip non-arguments 141 return (*this)->op_begin(); 142 } 143 144 IterTy arg_end() const { return (*this)->op_end() - getArgumentEndOffset(); } 145 bool arg_empty() const { return arg_end() == arg_begin(); } 146 unsigned arg_size() const { return unsigned(arg_end() - arg_begin()); } 147 148 /// getType - Return the type of the instruction that generated this call site 149 /// 150 Type *getType() const { return (*this)->getType(); } 151 152 /// getCaller - Return the caller function for this call site 153 /// 154 FunTy *getCaller() const { return (*this)->getParent()->getParent(); } 155 156 #define CALLSITE_DELEGATE_GETTER(METHOD) \ 157 InstrTy *II = getInstruction(); \ 158 return isCall() \ 159 ? cast<CallInst>(II)->METHOD \ 160 : cast<InvokeInst>(II)->METHOD 161 162 #define CALLSITE_DELEGATE_SETTER(METHOD) \ 163 InstrTy *II = getInstruction(); \ 164 if (isCall()) \ 165 cast<CallInst>(II)->METHOD; \ 166 else \ 167 cast<InvokeInst>(II)->METHOD 168 169 /// getCallingConv/setCallingConv - get or set the calling convention of the 170 /// call. 171 CallingConv::ID getCallingConv() const { 172 CALLSITE_DELEGATE_GETTER(getCallingConv()); 173 } 174 void setCallingConv(CallingConv::ID CC) { 175 CALLSITE_DELEGATE_SETTER(setCallingConv(CC)); 176 } 177 178 /// getAttributes/setAttributes - get or set the parameter attributes of 179 /// the call. 180 const AttributeSet &getAttributes() const { 181 CALLSITE_DELEGATE_GETTER(getAttributes()); 182 } 183 void setAttributes(const AttributeSet &PAL) { 184 CALLSITE_DELEGATE_SETTER(setAttributes(PAL)); 185 } 186 187 /// \brief Return true if this function has the given attribute. 188 bool hasFnAttr(Attribute::AttrKind A) const { 189 CALLSITE_DELEGATE_GETTER(hasFnAttr(A)); 190 } 191 192 /// \brief Return true if the call or the callee has the given attribute. 193 bool paramHasAttr(unsigned i, Attribute::AttrKind A) const { 194 CALLSITE_DELEGATE_GETTER(paramHasAttr(i, A)); 195 } 196 197 /// @brief Extract the alignment for a call or parameter (0=unknown). 198 uint16_t getParamAlignment(uint16_t i) const { 199 CALLSITE_DELEGATE_GETTER(getParamAlignment(i)); 200 } 201 202 /// @brief Return true if the call should not be inlined. 203 bool isNoInline() const { 204 CALLSITE_DELEGATE_GETTER(isNoInline()); 205 } 206 void setIsNoInline(bool Value = true) { 207 CALLSITE_DELEGATE_SETTER(setIsNoInline(Value)); 208 } 209 210 /// @brief Determine if the call does not access memory. 211 bool doesNotAccessMemory() const { 212 CALLSITE_DELEGATE_GETTER(doesNotAccessMemory()); 213 } 214 void setDoesNotAccessMemory() { 215 CALLSITE_DELEGATE_SETTER(setDoesNotAccessMemory()); 216 } 217 218 /// @brief Determine if the call does not access or only reads memory. 219 bool onlyReadsMemory() const { 220 CALLSITE_DELEGATE_GETTER(onlyReadsMemory()); 221 } 222 void setOnlyReadsMemory() { 223 CALLSITE_DELEGATE_SETTER(setOnlyReadsMemory()); 224 } 225 226 /// @brief Determine if the call cannot return. 227 bool doesNotReturn() const { 228 CALLSITE_DELEGATE_GETTER(doesNotReturn()); 229 } 230 void setDoesNotReturn() { 231 CALLSITE_DELEGATE_SETTER(setDoesNotReturn()); 232 } 233 234 /// @brief Determine if the call cannot unwind. 235 bool doesNotThrow() const { 236 CALLSITE_DELEGATE_GETTER(doesNotThrow()); 237 } 238 void setDoesNotThrow() { 239 CALLSITE_DELEGATE_SETTER(setDoesNotThrow()); 240 } 241 242 #undef CALLSITE_DELEGATE_GETTER 243 #undef CALLSITE_DELEGATE_SETTER 244 245 /// @brief Determine whether this argument is not captured. 246 bool doesNotCapture(unsigned ArgNo) const { 247 return paramHasAttr(ArgNo + 1, Attribute::NoCapture); 248 } 249 250 /// @brief Determine whether this argument is passed by value. 251 bool isByValArgument(unsigned ArgNo) const { 252 return paramHasAttr(ArgNo + 1, Attribute::ByVal); 253 } 254 255 /// hasArgument - Returns true if this CallSite passes the given Value* as an 256 /// argument to the called function. 257 bool hasArgument(const Value *Arg) const { 258 for (arg_iterator AI = this->arg_begin(), E = this->arg_end(); AI != E; 259 ++AI) 260 if (AI->get() == Arg) 261 return true; 262 return false; 263 } 264 265 private: 266 unsigned getArgumentEndOffset() const { 267 if (isCall()) 268 return 1; // Skip Callee 269 else 270 return 3; // Skip BB, BB, Callee 271 } 272 273 IterTy getCallee() const { 274 if (isCall()) // Skip Callee 275 return cast<CallInst>(getInstruction())->op_end() - 1; 276 else // Skip BB, BB, Callee 277 return cast<InvokeInst>(getInstruction())->op_end() - 3; 278 } 279 }; 280 281 class CallSite : public CallSiteBase<Function, Value, User, Instruction, 282 CallInst, InvokeInst, User::op_iterator> { 283 typedef CallSiteBase<Function, Value, User, Instruction, 284 CallInst, InvokeInst, User::op_iterator> Base; 285 public: 286 CallSite() {} 287 CallSite(Base B) : Base(B) {} 288 CallSite(Value* V) : Base(V) {} 289 CallSite(CallInst *CI) : Base(CI) {} 290 CallSite(InvokeInst *II) : Base(II) {} 291 CallSite(Instruction *II) : Base(II) {} 292 293 bool operator==(const CallSite &CS) const { return I == CS.I; } 294 bool operator!=(const CallSite &CS) const { return I != CS.I; } 295 bool operator<(const CallSite &CS) const { 296 return getInstruction() < CS.getInstruction(); 297 } 298 299 private: 300 User::op_iterator getCallee() const; 301 }; 302 303 /// ImmutableCallSite - establish a view to a call site for examination 304 class ImmutableCallSite : public CallSiteBase<> { 305 typedef CallSiteBase<> Base; 306 public: 307 ImmutableCallSite(const Value* V) : Base(V) {} 308 ImmutableCallSite(const CallInst *CI) : Base(CI) {} 309 ImmutableCallSite(const InvokeInst *II) : Base(II) {} 310 ImmutableCallSite(const Instruction *II) : Base(II) {} 311 ImmutableCallSite(CallSite CS) : Base(CS.getInstruction()) {} 312 }; 313 314 } // End llvm namespace 315 316 #endif 317