1 //===-- llvm/LLVMContext.h - Class for managing "global" state --*- 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 declares LLVMContext, a container of "global" state in LLVM, such 11 // as the global type and constant uniquing tables. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_IR_LLVMCONTEXT_H 16 #define LLVM_IR_LLVMCONTEXT_H 17 18 #include "llvm/Support/CBindingWrapping.h" 19 #include "llvm/Support/Options.h" 20 21 namespace llvm { 22 23 class LLVMContextImpl; 24 class StringRef; 25 class Twine; 26 class Instruction; 27 class Module; 28 class MDString; 29 class DICompositeType; 30 class SMDiagnostic; 31 class DiagnosticInfo; 32 enum DiagnosticSeverity : char; 33 template <typename T> class SmallVectorImpl; 34 class Function; 35 class DebugLoc; 36 class OptBisect; 37 38 /// This is an important class for using LLVM in a threaded context. It 39 /// (opaquely) owns and manages the core "global" data of LLVM's core 40 /// infrastructure, including the type and constant uniquing tables. 41 /// LLVMContext itself provides no locking guarantees, so you should be careful 42 /// to have one context per thread. 43 class LLVMContext { 44 public: 45 LLVMContextImpl *const pImpl; 46 LLVMContext(); 47 ~LLVMContext(); 48 49 // Pinned metadata names, which always have the same value. This is a 50 // compile-time performance optimization, not a correctness optimization. 51 enum { 52 MD_dbg = 0, // "dbg" 53 MD_tbaa = 1, // "tbaa" 54 MD_prof = 2, // "prof" 55 MD_fpmath = 3, // "fpmath" 56 MD_range = 4, // "range" 57 MD_tbaa_struct = 5, // "tbaa.struct" 58 MD_invariant_load = 6, // "invariant.load" 59 MD_alias_scope = 7, // "alias.scope" 60 MD_noalias = 8, // "noalias", 61 MD_nontemporal = 9, // "nontemporal" 62 MD_mem_parallel_loop_access = 10, // "llvm.mem.parallel_loop_access" 63 MD_nonnull = 11, // "nonnull" 64 MD_dereferenceable = 12, // "dereferenceable" 65 MD_dereferenceable_or_null = 13, // "dereferenceable_or_null" 66 MD_make_implicit = 14, // "make.implicit" 67 MD_unpredictable = 15, // "unpredictable" 68 MD_invariant_group = 16, // "invariant.group" 69 MD_align = 17, // "align" 70 MD_loop = 18, // "llvm.loop" 71 MD_type = 19, // "type" 72 }; 73 74 /// Known operand bundle tag IDs, which always have the same value. All 75 /// operand bundle tags that LLVM has special knowledge of are listed here. 76 /// Additionally, this scheme allows LLVM to efficiently check for specific 77 /// operand bundle tags without comparing strings. 78 enum { 79 OB_deopt = 0, // "deopt" 80 OB_funclet = 1, // "funclet" 81 OB_gc_transition = 2, // "gc-transition" 82 }; 83 84 /// getMDKindID - Return a unique non-zero ID for the specified metadata kind. 85 /// This ID is uniqued across modules in the current LLVMContext. 86 unsigned getMDKindID(StringRef Name) const; 87 88 /// getMDKindNames - Populate client supplied SmallVector with the name for 89 /// custom metadata IDs registered in this LLVMContext. 90 void getMDKindNames(SmallVectorImpl<StringRef> &Result) const; 91 92 /// getOperandBundleTags - Populate client supplied SmallVector with the 93 /// bundle tags registered in this LLVMContext. The bundle tags are ordered 94 /// by increasing bundle IDs. 95 /// \see LLVMContext::getOperandBundleTagID 96 void getOperandBundleTags(SmallVectorImpl<StringRef> &Result) const; 97 98 /// getOperandBundleTagID - Maps a bundle tag to an integer ID. Every bundle 99 /// tag registered with an LLVMContext has an unique ID. 100 uint32_t getOperandBundleTagID(StringRef Tag) const; 101 102 /// Define the GC for a function 103 void setGC(const Function &Fn, std::string GCName); 104 105 /// Return the GC for a function 106 const std::string &getGC(const Function &Fn); 107 108 /// Remove the GC for a function 109 void deleteGC(const Function &Fn); 110 111 /// Return true if the Context runtime configuration is set to discard all 112 /// value names. When true, only GlobalValue names will be available in the 113 /// IR. 114 bool shouldDiscardValueNames() const; 115 116 /// Set the Context runtime configuration to discard all value name (but 117 /// GlobalValue). Clients can use this flag to save memory and runtime, 118 /// especially in release mode. 119 void setDiscardValueNames(bool Discard); 120 121 /// Whether there is a string map for uniquing debug info 122 /// identifiers across the context. Off by default. 123 bool isODRUniquingDebugTypes() const; 124 void enableDebugTypeODRUniquing(); 125 void disableDebugTypeODRUniquing(); 126 127 typedef void (*InlineAsmDiagHandlerTy)(const SMDiagnostic&, void *Context, 128 unsigned LocCookie); 129 130 /// Defines the type of a diagnostic handler. 131 /// \see LLVMContext::setDiagnosticHandler. 132 /// \see LLVMContext::diagnose. 133 typedef void (*DiagnosticHandlerTy)(const DiagnosticInfo &DI, void *Context); 134 135 /// Defines the type of a yield callback. 136 /// \see LLVMContext::setYieldCallback. 137 typedef void (*YieldCallbackTy)(LLVMContext *Context, void *OpaqueHandle); 138 139 /// setInlineAsmDiagnosticHandler - This method sets a handler that is invoked 140 /// when problems with inline asm are detected by the backend. The first 141 /// argument is a function pointer and the second is a context pointer that 142 /// gets passed into the DiagHandler. 143 /// 144 /// LLVMContext doesn't take ownership or interpret either of these 145 /// pointers. 146 void setInlineAsmDiagnosticHandler(InlineAsmDiagHandlerTy DiagHandler, 147 void *DiagContext = nullptr); 148 149 /// getInlineAsmDiagnosticHandler - Return the diagnostic handler set by 150 /// setInlineAsmDiagnosticHandler. 151 InlineAsmDiagHandlerTy getInlineAsmDiagnosticHandler() const; 152 153 /// getInlineAsmDiagnosticContext - Return the diagnostic context set by 154 /// setInlineAsmDiagnosticHandler. 155 void *getInlineAsmDiagnosticContext() const; 156 157 /// setDiagnosticHandler - This method sets a handler that is invoked 158 /// when the backend needs to report anything to the user. The first 159 /// argument is a function pointer and the second is a context pointer that 160 /// gets passed into the DiagHandler. The third argument should be set to 161 /// true if the handler only expects enabled diagnostics. 162 /// 163 /// LLVMContext doesn't take ownership or interpret either of these 164 /// pointers. 165 void setDiagnosticHandler(DiagnosticHandlerTy DiagHandler, 166 void *DiagContext = nullptr, 167 bool RespectFilters = false); 168 169 /// getDiagnosticHandler - Return the diagnostic handler set by 170 /// setDiagnosticHandler. 171 DiagnosticHandlerTy getDiagnosticHandler() const; 172 173 /// getDiagnosticContext - Return the diagnostic context set by 174 /// setDiagnosticContext. 175 void *getDiagnosticContext() const; 176 177 /// \brief Get the prefix that should be printed in front of a diagnostic of 178 /// the given \p Severity 179 static const char *getDiagnosticMessagePrefix(DiagnosticSeverity Severity); 180 181 /// \brief Report a message to the currently installed diagnostic handler. 182 /// 183 /// This function returns, in particular in the case of error reporting 184 /// (DI.Severity == \a DS_Error), so the caller should leave the compilation 185 /// process in a self-consistent state, even though the generated code 186 /// need not be correct. 187 /// 188 /// The diagnostic message will be implicitly prefixed with a severity keyword 189 /// according to \p DI.getSeverity(), i.e., "error: " for \a DS_Error, 190 /// "warning: " for \a DS_Warning, and "note: " for \a DS_Note. 191 void diagnose(const DiagnosticInfo &DI); 192 193 /// \brief Registers a yield callback with the given context. 194 /// 195 /// The yield callback function may be called by LLVM to transfer control back 196 /// to the client that invoked the LLVM compilation. This can be used to yield 197 /// control of the thread, or perform periodic work needed by the client. 198 /// There is no guaranteed frequency at which callbacks must occur; in fact, 199 /// the client is not guaranteed to ever receive this callback. It is at the 200 /// sole discretion of LLVM to do so and only if it can guarantee that 201 /// suspending the thread won't block any forward progress in other LLVM 202 /// contexts in the same process. 203 /// 204 /// At a suspend point, the state of the current LLVM context is intentionally 205 /// undefined. No assumptions about it can or should be made. Only LLVM 206 /// context API calls that explicitly state that they can be used during a 207 /// yield callback are allowed to be used. Any other API calls into the 208 /// context are not supported until the yield callback function returns 209 /// control to LLVM. Other LLVM contexts are unaffected by this restriction. 210 void setYieldCallback(YieldCallbackTy Callback, void *OpaqueHandle); 211 212 /// \brief Calls the yield callback (if applicable). 213 /// 214 /// This transfers control of the current thread back to the client, which may 215 /// suspend the current thread. Only call this method when LLVM doesn't hold 216 /// any global mutex or cannot block the execution in another LLVM context. 217 void yield(); 218 219 /// emitError - Emit an error message to the currently installed error handler 220 /// with optional location information. This function returns, so code should 221 /// be prepared to drop the erroneous construct on the floor and "not crash". 222 /// The generated code need not be correct. The error message will be 223 /// implicitly prefixed with "error: " and should not end with a ".". 224 void emitError(unsigned LocCookie, const Twine &ErrorStr); 225 void emitError(const Instruction *I, const Twine &ErrorStr); 226 void emitError(const Twine &ErrorStr); 227 228 /// \brief Query for a debug option's value. 229 /// 230 /// This function returns typed data populated from command line parsing. 231 template <typename ValT, typename Base, ValT(Base::*Mem)> 232 ValT getOption() const { 233 return OptionRegistry::instance().template get<ValT, Base, Mem>(); 234 } 235 236 /// \brief Access the object which manages optimization bisection for failure 237 /// analysis. 238 OptBisect &getOptBisect(); 239 private: 240 LLVMContext(LLVMContext&) = delete; 241 void operator=(LLVMContext&) = delete; 242 243 /// addModule - Register a module as being instantiated in this context. If 244 /// the context is deleted, the module will be deleted as well. 245 void addModule(Module*); 246 247 /// removeModule - Unregister a module from this context. 248 void removeModule(Module*); 249 250 // Module needs access to the add/removeModule methods. 251 friend class Module; 252 }; 253 254 // Create wrappers for C Binding types (see CBindingWrapping.h). 255 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(LLVMContext, LLVMContextRef) 256 257 /* Specialized opaque context conversions. 258 */ 259 inline LLVMContext **unwrap(LLVMContextRef* Tys) { 260 return reinterpret_cast<LLVMContext**>(Tys); 261 } 262 263 inline LLVMContextRef *wrap(const LLVMContext **Tys) { 264 return reinterpret_cast<LLVMContextRef*>(const_cast<LLVMContext**>(Tys)); 265 } 266 267 } 268 269 #endif 270
