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/IR/DiagnosticHandler.h"
20#include "llvm/Support/CBindingWrapping.h"
21#include "llvm/Support/Options.h"
22#include <cstdint>
23#include <memory>
24#include <string>
25
26namespace llvm {
27
28class DiagnosticInfo;
29enum DiagnosticSeverity : char;
30class Function;
31class Instruction;
32class LLVMContextImpl;
33class Module;
34class OptPassGate;
35template <typename T> class SmallVectorImpl;
36class SMDiagnostic;
37class StringRef;
38class Twine;
39
40namespace yaml {
41
42class Output;
43
44} // end namespace yaml
45
46namespace SyncScope {
47
48typedef uint8_t ID;
49
50/// Known synchronization scope IDs, which always have the same value. All
51/// synchronization scope IDs that LLVM has special knowledge of are listed
52/// here. Additionally, this scheme allows LLVM to efficiently check for
53/// specific synchronization scope ID without comparing strings.
54enum {
55 /// Synchronized with respect to signal handlers executing in the same thread.
56 SingleThread = 0,
57
58 /// Synchronized with respect to all concurrently executing threads.
59 System = 1
60};
61
62} // end namespace SyncScope
63
64/// This is an important class for using LLVM in a threaded context. It
65/// (opaquely) owns and manages the core "global" data of LLVM's core
66/// infrastructure, including the type and constant uniquing tables.
67/// LLVMContext itself provides no locking guarantees, so you should be careful
68/// to have one context per thread.
69class LLVMContext {
70public:
71 LLVMContextImpl *const pImpl;
72 LLVMContext();
73 LLVMContext(LLVMContext &) = delete;
74 LLVMContext &operator=(const LLVMContext &) = delete;
75 ~LLVMContext();
76
77 // Pinned metadata names, which always have the same value. This is a
78 // compile-time performance optimization, not a correctness optimization.
79 enum : unsigned {
80 MD_dbg = 0, // "dbg"
81 MD_tbaa = 1, // "tbaa"
82 MD_prof = 2, // "prof"
83 MD_fpmath = 3, // "fpmath"
84 MD_range = 4, // "range"
85 MD_tbaa_struct = 5, // "tbaa.struct"
86 MD_invariant_load = 6, // "invariant.load"
87 MD_alias_scope = 7, // "alias.scope"
88 MD_noalias = 8, // "noalias",
89 MD_nontemporal = 9, // "nontemporal"
90 MD_mem_parallel_loop_access = 10, // "llvm.mem.parallel_loop_access"
91 MD_nonnull = 11, // "nonnull"
92 MD_dereferenceable = 12, // "dereferenceable"
93 MD_dereferenceable_or_null = 13, // "dereferenceable_or_null"
94 MD_make_implicit = 14, // "make.implicit"
95 MD_unpredictable = 15, // "unpredictable"
96 MD_invariant_group = 16, // "invariant.group"
97 MD_align = 17, // "align"
98 MD_loop = 18, // "llvm.loop"
99 MD_type = 19, // "type"
100 MD_section_prefix = 20, // "section_prefix"
101 MD_absolute_symbol = 21, // "absolute_symbol"
102 MD_associated = 22, // "associated"
103 MD_callees = 23, // "callees"
104 MD_irr_loop = 24, // "irr_loop"
105 MD_access_group = 25, // "llvm.access.group"
106 };
107
108 /// Known operand bundle tag IDs, which always have the same value. All
109 /// operand bundle tags that LLVM has special knowledge of are listed here.
110 /// Additionally, this scheme allows LLVM to efficiently check for specific
111 /// operand bundle tags without comparing strings.
112 enum : unsigned {
113 OB_deopt = 0, // "deopt"
114 OB_funclet = 1, // "funclet"
115 OB_gc_transition = 2, // "gc-transition"
116 };
117
118 /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
119 /// This ID is uniqued across modules in the current LLVMContext.
120 unsigned getMDKindID(StringRef Name) const;
121
122 /// getMDKindNames - Populate client supplied SmallVector with the name for
123 /// custom metadata IDs registered in this LLVMContext.
124 void getMDKindNames(SmallVectorImpl<StringRef> &Result) const;
125
126 /// getOperandBundleTags - Populate client supplied SmallVector with the
127 /// bundle tags registered in this LLVMContext. The bundle tags are ordered
128 /// by increasing bundle IDs.
129 /// \see LLVMContext::getOperandBundleTagID
130 void getOperandBundleTags(SmallVectorImpl<StringRef> &Result) const;
131
132 /// getOperandBundleTagID - Maps a bundle tag to an integer ID. Every bundle
133 /// tag registered with an LLVMContext has an unique ID.
134 uint32_t getOperandBundleTagID(StringRef Tag) const;
135
136 /// getOrInsertSyncScopeID - Maps synchronization scope name to
137 /// synchronization scope ID. Every synchronization scope registered with
138 /// LLVMContext has unique ID except pre-defined ones.
139 SyncScope::ID getOrInsertSyncScopeID(StringRef SSN);
140
141 /// getSyncScopeNames - Populates client supplied SmallVector with
142 /// synchronization scope names registered with LLVMContext. Synchronization
143 /// scope names are ordered by increasing synchronization scope IDs.
144 void getSyncScopeNames(SmallVectorImpl<StringRef> &SSNs) const;
145
146 /// Define the GC for a function
147 void setGC(const Function &Fn, std::string GCName);
148
149 /// Return the GC for a function
150 const std::string &getGC(const Function &Fn);
151
152 /// Remove the GC for a function
153 void deleteGC(const Function &Fn);
154
155 /// Return true if the Context runtime configuration is set to discard all
156 /// value names. When true, only GlobalValue names will be available in the
157 /// IR.
158 bool shouldDiscardValueNames() const;
159
160 /// Set the Context runtime configuration to discard all value name (but
161 /// GlobalValue). Clients can use this flag to save memory and runtime,
162 /// especially in release mode.
163 void setDiscardValueNames(bool Discard);
164
165 /// Whether there is a string map for uniquing debug info
166 /// identifiers across the context. Off by default.
167 bool isODRUniquingDebugTypes() const;
168 void enableDebugTypeODRUniquing();
169 void disableDebugTypeODRUniquing();
170
171 using InlineAsmDiagHandlerTy = void (*)(const SMDiagnostic&, void *Context,
172 unsigned LocCookie);
173
174 /// Defines the type of a yield callback.
175 /// \see LLVMContext::setYieldCallback.
176 using YieldCallbackTy = void (*)(LLVMContext *Context, void *OpaqueHandle);
177
178 /// setInlineAsmDiagnosticHandler - This method sets a handler that is invoked
179 /// when problems with inline asm are detected by the backend. The first
180 /// argument is a function pointer and the second is a context pointer that
181 /// gets passed into the DiagHandler.
182 ///
183 /// LLVMContext doesn't take ownership or interpret either of these
184 /// pointers.
185 void setInlineAsmDiagnosticHandler(InlineAsmDiagHandlerTy DiagHandler,
186 void *DiagContext = nullptr);
187
188 /// getInlineAsmDiagnosticHandler - Return the diagnostic handler set by
189 /// setInlineAsmDiagnosticHandler.
190 InlineAsmDiagHandlerTy getInlineAsmDiagnosticHandler() const;
191
192 /// getInlineAsmDiagnosticContext - Return the diagnostic context set by
193 /// setInlineAsmDiagnosticHandler.
194 void *getInlineAsmDiagnosticContext() const;
195
196 /// setDiagnosticHandlerCallBack - This method sets a handler call back
197 /// that is invoked when the backend needs to report anything to the user.
198 /// The first argument is a function pointer and the second is a context pointer
199 /// that gets passed into the DiagHandler. The third argument should be set to
200 /// true if the handler only expects enabled diagnostics.
201 ///
202 /// LLVMContext doesn't take ownership or interpret either of these
203 /// pointers.
204 void setDiagnosticHandlerCallBack(
205 DiagnosticHandler::DiagnosticHandlerTy DiagHandler,
206 void *DiagContext = nullptr, bool RespectFilters = false);
207
208 /// setDiagnosticHandler - This method sets unique_ptr to object of DiagnosticHandler
209 /// to provide custom diagnostic handling. The first argument is unique_ptr of object
210 /// of type DiagnosticHandler or a derived of that. The third argument should be
211 /// set to true if the handler only expects enabled diagnostics.
212 ///
213 /// Ownership of this pointer is moved to LLVMContextImpl.
214 void setDiagnosticHandler(std::unique_ptr<DiagnosticHandler> &&DH,
215 bool RespectFilters = false);
216
217 /// getDiagnosticHandlerCallBack - Return the diagnostic handler call back set by
218 /// setDiagnosticHandlerCallBack.
219 DiagnosticHandler::DiagnosticHandlerTy getDiagnosticHandlerCallBack() const;
220
221 /// getDiagnosticContext - Return the diagnostic context set by
222 /// setDiagnosticContext.
223 void *getDiagnosticContext() const;
224
225 /// getDiagHandlerPtr - Returns const raw pointer of DiagnosticHandler set by
226 /// setDiagnosticHandler.
227 const DiagnosticHandler *getDiagHandlerPtr() const;
228
229 /// getDiagnosticHandler - transfers owenership of DiagnosticHandler unique_ptr
230 /// to caller.
231 std::unique_ptr<DiagnosticHandler> getDiagnosticHandler();
232
233 /// Return if a code hotness metric should be included in optimization
234 /// diagnostics.
235 bool getDiagnosticsHotnessRequested() const;
236 /// Set if a code hotness metric should be included in optimization
237 /// diagnostics.
238 void setDiagnosticsHotnessRequested(bool Requested);
239
240 /// Return the minimum hotness value a diagnostic would need in order
241 /// to be included in optimization diagnostics. If there is no minimum, this
242 /// returns None.
243 uint64_t getDiagnosticsHotnessThreshold() const;
244
245 /// Set the minimum hotness value a diagnostic needs in order to be
246 /// included in optimization diagnostics.
247 void setDiagnosticsHotnessThreshold(uint64_t Threshold);
248
249 /// Return the YAML file used by the backend to save optimization
250 /// diagnostics. If null, diagnostics are not saved in a file but only
251 /// emitted via the diagnostic handler.
252 yaml::Output *getDiagnosticsOutputFile();
253 /// Set the diagnostics output file used for optimization diagnostics.
254 ///
255 /// By default or if invoked with null, diagnostics are not saved in a file
256 /// but only emitted via the diagnostic handler. Even if an output file is
257 /// set, the handler is invoked for each diagnostic message.
258 void setDiagnosticsOutputFile(std::unique_ptr<yaml::Output> F);
259
260 /// Get the prefix that should be printed in front of a diagnostic of
261 /// the given \p Severity
262 static const char *getDiagnosticMessagePrefix(DiagnosticSeverity Severity);
263
264 /// Report a message to the currently installed diagnostic handler.
265 ///
266 /// This function returns, in particular in the case of error reporting
267 /// (DI.Severity == \a DS_Error), so the caller should leave the compilation
268 /// process in a self-consistent state, even though the generated code
269 /// need not be correct.
270 ///
271 /// The diagnostic message will be implicitly prefixed with a severity keyword
272 /// according to \p DI.getSeverity(), i.e., "error: " for \a DS_Error,
273 /// "warning: " for \a DS_Warning, and "note: " for \a DS_Note.
274 void diagnose(const DiagnosticInfo &DI);
275
276 /// Registers a yield callback with the given context.
277 ///
278 /// The yield callback function may be called by LLVM to transfer control back
279 /// to the client that invoked the LLVM compilation. This can be used to yield
280 /// control of the thread, or perform periodic work needed by the client.
281 /// There is no guaranteed frequency at which callbacks must occur; in fact,
282 /// the client is not guaranteed to ever receive this callback. It is at the
283 /// sole discretion of LLVM to do so and only if it can guarantee that
284 /// suspending the thread won't block any forward progress in other LLVM
285 /// contexts in the same process.
286 ///
287 /// At a suspend point, the state of the current LLVM context is intentionally
288 /// undefined. No assumptions about it can or should be made. Only LLVM
289 /// context API calls that explicitly state that they can be used during a
290 /// yield callback are allowed to be used. Any other API calls into the
291 /// context are not supported until the yield callback function returns
292 /// control to LLVM. Other LLVM contexts are unaffected by this restriction.
293 void setYieldCallback(YieldCallbackTy Callback, void *OpaqueHandle);
294
295 /// Calls the yield callback (if applicable).
296 ///
297 /// This transfers control of the current thread back to the client, which may
298 /// suspend the current thread. Only call this method when LLVM doesn't hold
299 /// any global mutex or cannot block the execution in another LLVM context.
300 void yield();
301
302 /// emitError - Emit an error message to the currently installed error handler
303 /// with optional location information. This function returns, so code should
304 /// be prepared to drop the erroneous construct on the floor and "not crash".
305 /// The generated code need not be correct. The error message will be
306 /// implicitly prefixed with "error: " and should not end with a ".".
307 void emitError(unsigned LocCookie, const Twine &ErrorStr);
308 void emitError(const Instruction *I, const Twine &ErrorStr);
309 void emitError(const Twine &ErrorStr);
310
311 /// Query for a debug option's value.
312 ///
313 /// This function returns typed data populated from command line parsing.
314 template <typename ValT, typename Base, ValT(Base::*Mem)>
315 ValT getOption() const {
316 return OptionRegistry::instance().template get<ValT, Base, Mem>();
317 }
318
319 /// Access the object which can disable optional passes and individual
320 /// optimizations at compile time.
321 OptPassGate &getOptPassGate() const;
322
323 /// Set the object which can disable optional passes and individual
324 /// optimizations at compile time.
325 ///
326 /// The lifetime of the object must be guaranteed to extend as long as the
327 /// LLVMContext is used by compilation.
328 void setOptPassGate(OptPassGate&);
329
330private:
331 // Module needs access to the add/removeModule methods.
332 friend class Module;
333
334 /// addModule - Register a module as being instantiated in this context. If
335 /// the context is deleted, the module will be deleted as well.
336 void addModule(Module*);
337
338 /// removeModule - Unregister a module from this context.
339 void removeModule(Module*);
340};
341
342// Create wrappers for C Binding types (see CBindingWrapping.h).
343DEFINE_SIMPLE_CONVERSION_FUNCTIONS(LLVMContext, LLVMContextRef)
344
345/* Specialized opaque context conversions.
346 */
347inline LLVMContext **unwrap(LLVMContextRef* Tys) {
348 return reinterpret_cast<LLVMContext**>(Tys);
349}
350
351inline LLVMContextRef *wrap(const LLVMContext **Tys) {
352 return reinterpret_cast<LLVMContextRef*>(const_cast<LLVMContext**>(Tys));
353}
354
355} // end namespace llvm
356
357#endif // LLVM_IR_LLVMCONTEXT_H
358