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-c/Types.h" 19#include "llvm/Support/CBindingWrapping.h" 20#include "llvm/Support/Options.h" 21#include <cstdint> 22#include <memory> 23#include <string> 24 25namespace llvm { 26 27class DiagnosticInfo; 28enum DiagnosticSeverity : char; 29class Function; 30class Instruction; 31class LLVMContextImpl; 32class Module; 33class OptBisect; 34template <typename T> class SmallVectorImpl; 35class SMDiagnostic; 36class StringRef; 37class Twine; 38 39namespace yaml { 40class Output; 41} // end namespace yaml 42 43/// This is an important class for using LLVM in a threaded context. It 44/// (opaquely) owns and manages the core "global" data of LLVM's core 45/// infrastructure, including the type and constant uniquing tables. 46/// LLVMContext itself provides no locking guarantees, so you should be careful 47/// to have one context per thread. 48class LLVMContext { 49public: 50 LLVMContextImpl *const pImpl; 51 LLVMContext(); 52 LLVMContext(LLVMContext &) = delete; 53 LLVMContext &operator=(const LLVMContext &) = delete; 54 ~LLVMContext(); 55 56 // Pinned metadata names, which always have the same value. This is a 57 // compile-time performance optimization, not a correctness optimization. 58 enum { 59 MD_dbg = 0, // "dbg" 60 MD_tbaa = 1, // "tbaa" 61 MD_prof = 2, // "prof" 62 MD_fpmath = 3, // "fpmath" 63 MD_range = 4, // "range" 64 MD_tbaa_struct = 5, // "tbaa.struct" 65 MD_invariant_load = 6, // "invariant.load" 66 MD_alias_scope = 7, // "alias.scope" 67 MD_noalias = 8, // "noalias", 68 MD_nontemporal = 9, // "nontemporal" 69 MD_mem_parallel_loop_access = 10, // "llvm.mem.parallel_loop_access" 70 MD_nonnull = 11, // "nonnull" 71 MD_dereferenceable = 12, // "dereferenceable" 72 MD_dereferenceable_or_null = 13, // "dereferenceable_or_null" 73 MD_make_implicit = 14, // "make.implicit" 74 MD_unpredictable = 15, // "unpredictable" 75 MD_invariant_group = 16, // "invariant.group" 76 MD_align = 17, // "align" 77 MD_loop = 18, // "llvm.loop" 78 MD_type = 19, // "type" 79 MD_section_prefix = 20, // "section_prefix" 80 MD_absolute_symbol = 21, // "absolute_symbol" 81 }; 82 83 /// Known operand bundle tag IDs, which always have the same value. All 84 /// operand bundle tags that LLVM has special knowledge of are listed here. 85 /// Additionally, this scheme allows LLVM to efficiently check for specific 86 /// operand bundle tags without comparing strings. 87 enum { 88 OB_deopt = 0, // "deopt" 89 OB_funclet = 1, // "funclet" 90 OB_gc_transition = 2, // "gc-transition" 91 }; 92 93 /// getMDKindID - Return a unique non-zero ID for the specified metadata kind. 94 /// This ID is uniqued across modules in the current LLVMContext. 95 unsigned getMDKindID(StringRef Name) const; 96 97 /// getMDKindNames - Populate client supplied SmallVector with the name for 98 /// custom metadata IDs registered in this LLVMContext. 99 void getMDKindNames(SmallVectorImpl<StringRef> &Result) const; 100 101 /// getOperandBundleTags - Populate client supplied SmallVector with the 102 /// bundle tags registered in this LLVMContext. The bundle tags are ordered 103 /// by increasing bundle IDs. 104 /// \see LLVMContext::getOperandBundleTagID 105 void getOperandBundleTags(SmallVectorImpl<StringRef> &Result) const; 106 107 /// getOperandBundleTagID - Maps a bundle tag to an integer ID. Every bundle 108 /// tag registered with an LLVMContext has an unique ID. 109 uint32_t getOperandBundleTagID(StringRef Tag) const; 110 111 /// Define the GC for a function 112 void setGC(const Function &Fn, std::string GCName); 113 114 /// Return the GC for a function 115 const std::string &getGC(const Function &Fn); 116 117 /// Remove the GC for a function 118 void deleteGC(const Function &Fn); 119 120 /// Return true if the Context runtime configuration is set to discard all 121 /// value names. When true, only GlobalValue names will be available in the 122 /// IR. 123 bool shouldDiscardValueNames() const; 124 125 /// Set the Context runtime configuration to discard all value name (but 126 /// GlobalValue). Clients can use this flag to save memory and runtime, 127 /// especially in release mode. 128 void setDiscardValueNames(bool Discard); 129 130 /// Whether there is a string map for uniquing debug info 131 /// identifiers across the context. Off by default. 132 bool isODRUniquingDebugTypes() const; 133 void enableDebugTypeODRUniquing(); 134 void disableDebugTypeODRUniquing(); 135 136 typedef void (*InlineAsmDiagHandlerTy)(const SMDiagnostic&, void *Context, 137 unsigned LocCookie); 138 139 /// Defines the type of a diagnostic handler. 140 /// \see LLVMContext::setDiagnosticHandler. 141 /// \see LLVMContext::diagnose. 142 typedef void (*DiagnosticHandlerTy)(const DiagnosticInfo &DI, void *Context); 143 144 /// Defines the type of a yield callback. 145 /// \see LLVMContext::setYieldCallback. 146 typedef void (*YieldCallbackTy)(LLVMContext *Context, void *OpaqueHandle); 147 148 /// setInlineAsmDiagnosticHandler - This method sets a handler that is invoked 149 /// when problems with inline asm are detected by the backend. The first 150 /// argument is a function pointer and the second is a context pointer that 151 /// gets passed into the DiagHandler. 152 /// 153 /// LLVMContext doesn't take ownership or interpret either of these 154 /// pointers. 155 void setInlineAsmDiagnosticHandler(InlineAsmDiagHandlerTy DiagHandler, 156 void *DiagContext = nullptr); 157 158 /// getInlineAsmDiagnosticHandler - Return the diagnostic handler set by 159 /// setInlineAsmDiagnosticHandler. 160 InlineAsmDiagHandlerTy getInlineAsmDiagnosticHandler() const; 161 162 /// getInlineAsmDiagnosticContext - Return the diagnostic context set by 163 /// setInlineAsmDiagnosticHandler. 164 void *getInlineAsmDiagnosticContext() const; 165 166 /// setDiagnosticHandler - This method sets a handler that is invoked 167 /// when the backend needs to report anything to the user. The first 168 /// argument is a function pointer and the second is a context pointer that 169 /// gets passed into the DiagHandler. The third argument should be set to 170 /// true if the handler only expects enabled diagnostics. 171 /// 172 /// LLVMContext doesn't take ownership or interpret either of these 173 /// pointers. 174 void setDiagnosticHandler(DiagnosticHandlerTy DiagHandler, 175 void *DiagContext = nullptr, 176 bool RespectFilters = false); 177 178 /// getDiagnosticHandler - Return the diagnostic handler set by 179 /// setDiagnosticHandler. 180 DiagnosticHandlerTy getDiagnosticHandler() const; 181 182 /// getDiagnosticContext - Return the diagnostic context set by 183 /// setDiagnosticContext. 184 void *getDiagnosticContext() const; 185 186 /// \brief Return if a code hotness metric should be included in optimization 187 /// diagnostics. 188 bool getDiagnosticHotnessRequested() const; 189 /// \brief Set if a code hotness metric should be included in optimization 190 /// diagnostics. 191 void setDiagnosticHotnessRequested(bool Requested); 192 193 /// \brief Return the YAML file used by the backend to save optimization 194 /// diagnostics. If null, diagnostics are not saved in a file but only 195 /// emitted via the diagnostic handler. 196 yaml::Output *getDiagnosticsOutputFile(); 197 /// Set the diagnostics output file used for optimization diagnostics. 198 /// 199 /// By default or if invoked with null, diagnostics are not saved in a file 200 /// but only emitted via the diagnostic handler. Even if an output file is 201 /// set, the handler is invoked for each diagnostic message. 202 void setDiagnosticsOutputFile(std::unique_ptr<yaml::Output> F); 203 204 /// \brief Get the prefix that should be printed in front of a diagnostic of 205 /// the given \p Severity 206 static const char *getDiagnosticMessagePrefix(DiagnosticSeverity Severity); 207 208 /// \brief Report a message to the currently installed diagnostic handler. 209 /// 210 /// This function returns, in particular in the case of error reporting 211 /// (DI.Severity == \a DS_Error), so the caller should leave the compilation 212 /// process in a self-consistent state, even though the generated code 213 /// need not be correct. 214 /// 215 /// The diagnostic message will be implicitly prefixed with a severity keyword 216 /// according to \p DI.getSeverity(), i.e., "error: " for \a DS_Error, 217 /// "warning: " for \a DS_Warning, and "note: " for \a DS_Note. 218 void diagnose(const DiagnosticInfo &DI); 219 220 /// \brief Registers a yield callback with the given context. 221 /// 222 /// The yield callback function may be called by LLVM to transfer control back 223 /// to the client that invoked the LLVM compilation. This can be used to yield 224 /// control of the thread, or perform periodic work needed by the client. 225 /// There is no guaranteed frequency at which callbacks must occur; in fact, 226 /// the client is not guaranteed to ever receive this callback. It is at the 227 /// sole discretion of LLVM to do so and only if it can guarantee that 228 /// suspending the thread won't block any forward progress in other LLVM 229 /// contexts in the same process. 230 /// 231 /// At a suspend point, the state of the current LLVM context is intentionally 232 /// undefined. No assumptions about it can or should be made. Only LLVM 233 /// context API calls that explicitly state that they can be used during a 234 /// yield callback are allowed to be used. Any other API calls into the 235 /// context are not supported until the yield callback function returns 236 /// control to LLVM. Other LLVM contexts are unaffected by this restriction. 237 void setYieldCallback(YieldCallbackTy Callback, void *OpaqueHandle); 238 239 /// \brief Calls the yield callback (if applicable). 240 /// 241 /// This transfers control of the current thread back to the client, which may 242 /// suspend the current thread. Only call this method when LLVM doesn't hold 243 /// any global mutex or cannot block the execution in another LLVM context. 244 void yield(); 245 246 /// emitError - Emit an error message to the currently installed error handler 247 /// with optional location information. This function returns, so code should 248 /// be prepared to drop the erroneous construct on the floor and "not crash". 249 /// The generated code need not be correct. The error message will be 250 /// implicitly prefixed with "error: " and should not end with a ".". 251 void emitError(unsigned LocCookie, const Twine &ErrorStr); 252 void emitError(const Instruction *I, const Twine &ErrorStr); 253 void emitError(const Twine &ErrorStr); 254 255 /// \brief Query for a debug option's value. 256 /// 257 /// This function returns typed data populated from command line parsing. 258 template <typename ValT, typename Base, ValT(Base::*Mem)> 259 ValT getOption() const { 260 return OptionRegistry::instance().template get<ValT, Base, Mem>(); 261 } 262 263 /// \brief Access the object which manages optimization bisection for failure 264 /// analysis. 265 OptBisect &getOptBisect(); 266private: 267 // Module needs access to the add/removeModule methods. 268 friend class Module; 269 270 /// addModule - Register a module as being instantiated in this context. If 271 /// the context is deleted, the module will be deleted as well. 272 void addModule(Module*); 273 274 /// removeModule - Unregister a module from this context. 275 void removeModule(Module*); 276}; 277 278// Create wrappers for C Binding types (see CBindingWrapping.h). 279DEFINE_SIMPLE_CONVERSION_FUNCTIONS(LLVMContext, LLVMContextRef) 280 281/* Specialized opaque context conversions. 282 */ 283inline LLVMContext **unwrap(LLVMContextRef* Tys) { 284 return reinterpret_cast<LLVMContext**>(Tys); 285} 286 287inline LLVMContextRef *wrap(const LLVMContext **Tys) { 288 return reinterpret_cast<LLVMContextRef*>(const_cast<LLVMContext**>(Tys)); 289} 290 291} // end namespace llvm 292 293#endif // LLVM_IR_LLVMCONTEXT_H 294