LLVM  6.0.0svn
LLVMContext.h
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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"
21 #include "llvm/Support/Options.h"
22 #include <cstdint>
23 #include <memory>
24 #include <string>
25 
26 namespace llvm {
27 
28 class DiagnosticInfo;
30 class Function;
31 class Instruction;
32 class LLVMContextImpl;
33 class Module;
34 class OptBisect;
35 template <typename T> class SmallVectorImpl;
36 class SMDiagnostic;
37 class StringRef;
38 class Twine;
39 
40 namespace yaml {
41 
42 class Output;
43 
44 } // end namespace yaml
45 
46 namespace SyncScope {
47 
48 typedef 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.
54 enum {
55  /// Synchronized with respect to signal handlers executing in the same thread.
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.
69 class LLVMContext {
70 public:
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 {
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  };
106 
107  /// Known operand bundle tag IDs, which always have the same value. All
108  /// operand bundle tags that LLVM has special knowledge of are listed here.
109  /// Additionally, this scheme allows LLVM to efficiently check for specific
110  /// operand bundle tags without comparing strings.
111  enum {
112  OB_deopt = 0, // "deopt"
113  OB_funclet = 1, // "funclet"
114  OB_gc_transition = 2, // "gc-transition"
115  };
116 
117  /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
118  /// This ID is uniqued across modules in the current LLVMContext.
119  unsigned getMDKindID(StringRef Name) const;
120 
121  /// getMDKindNames - Populate client supplied SmallVector with the name for
122  /// custom metadata IDs registered in this LLVMContext.
123  void getMDKindNames(SmallVectorImpl<StringRef> &Result) const;
124 
125  /// getOperandBundleTags - Populate client supplied SmallVector with the
126  /// bundle tags registered in this LLVMContext. The bundle tags are ordered
127  /// by increasing bundle IDs.
128  /// \see LLVMContext::getOperandBundleTagID
129  void getOperandBundleTags(SmallVectorImpl<StringRef> &Result) const;
130 
131  /// getOperandBundleTagID - Maps a bundle tag to an integer ID. Every bundle
132  /// tag registered with an LLVMContext has an unique ID.
133  uint32_t getOperandBundleTagID(StringRef Tag) const;
134 
135  /// getOrInsertSyncScopeID - Maps synchronization scope name to
136  /// synchronization scope ID. Every synchronization scope registered with
137  /// LLVMContext has unique ID except pre-defined ones.
138  SyncScope::ID getOrInsertSyncScopeID(StringRef SSN);
139 
140  /// getSyncScopeNames - Populates client supplied SmallVector with
141  /// synchronization scope names registered with LLVMContext. Synchronization
142  /// scope names are ordered by increasing synchronization scope IDs.
143  void getSyncScopeNames(SmallVectorImpl<StringRef> &SSNs) const;
144 
145  /// Define the GC for a function
146  void setGC(const Function &Fn, std::string GCName);
147 
148  /// Return the GC for a function
149  const std::string &getGC(const Function &Fn);
150 
151  /// Remove the GC for a function
152  void deleteGC(const Function &Fn);
153 
154  /// Return true if the Context runtime configuration is set to discard all
155  /// value names. When true, only GlobalValue names will be available in the
156  /// IR.
157  bool shouldDiscardValueNames() const;
158 
159  /// Set the Context runtime configuration to discard all value name (but
160  /// GlobalValue). Clients can use this flag to save memory and runtime,
161  /// especially in release mode.
162  void setDiscardValueNames(bool Discard);
163 
164  /// Whether there is a string map for uniquing debug info
165  /// identifiers across the context. Off by default.
166  bool isODRUniquingDebugTypes() const;
167  void enableDebugTypeODRUniquing();
168  void disableDebugTypeODRUniquing();
169 
170  using InlineAsmDiagHandlerTy = void (*)(const SMDiagnostic&, void *Context,
171  unsigned LocCookie);
172 
173  /// Defines the type of a yield callback.
174  /// \see LLVMContext::setYieldCallback.
175  using YieldCallbackTy = void (*)(LLVMContext *Context, void *OpaqueHandle);
176 
177  /// setInlineAsmDiagnosticHandler - This method sets a handler that is invoked
178  /// when problems with inline asm are detected by the backend. The first
179  /// argument is a function pointer and the second is a context pointer that
180  /// gets passed into the DiagHandler.
181  ///
182  /// LLVMContext doesn't take ownership or interpret either of these
183  /// pointers.
184  void setInlineAsmDiagnosticHandler(InlineAsmDiagHandlerTy DiagHandler,
185  void *DiagContext = nullptr);
186 
187  /// getInlineAsmDiagnosticHandler - Return the diagnostic handler set by
188  /// setInlineAsmDiagnosticHandler.
189  InlineAsmDiagHandlerTy getInlineAsmDiagnosticHandler() const;
190 
191  /// getInlineAsmDiagnosticContext - Return the diagnostic context set by
192  /// setInlineAsmDiagnosticHandler.
193  void *getInlineAsmDiagnosticContext() const;
194 
195  /// setDiagnosticHandlerCallBack - This method sets a handler call back
196  /// that is invoked when the backend needs to report anything to the user.
197  /// The first argument is a function pointer and the second is a context pointer
198  /// that gets passed into the DiagHandler. The third argument should be set to
199  /// true if the handler only expects enabled diagnostics.
200  ///
201  /// LLVMContext doesn't take ownership or interpret either of these
202  /// pointers.
203  void setDiagnosticHandlerCallBack(
205  void *DiagContext = nullptr, bool RespectFilters = false);
206 
207  /// setDiagnosticHandler - This method sets unique_ptr to object of DiagnosticHandler
208  /// to provide custom diagnostic handling. The first argument is unique_ptr of object
209  /// of type DiagnosticHandler or a derived of that. The third argument should be
210  /// set to true if the handler only expects enabled diagnostics.
211  ///
212  /// Ownership of this pointer is moved to LLVMContextImpl.
213  void setDiagnosticHandler(std::unique_ptr<DiagnosticHandler> &&DH,
214  bool RespectFilters = false);
215 
216  /// getDiagnosticHandlerCallBack - Return the diagnostic handler call back set by
217  /// setDiagnosticHandlerCallBack.
218  DiagnosticHandler::DiagnosticHandlerTy getDiagnosticHandlerCallBack() const;
219 
220  /// getDiagnosticContext - Return the diagnostic context set by
221  /// setDiagnosticContext.
222  void *getDiagnosticContext() const;
223 
224  /// getDiagHandlerPtr - Returns const raw pointer of DiagnosticHandler set by
225  /// setDiagnosticHandler.
226  const DiagnosticHandler *getDiagHandlerPtr() const;
227 
228  /// getDiagnosticHandler - transfers owenership of DiagnosticHandler unique_ptr
229  /// to caller.
230  std::unique_ptr<DiagnosticHandler> getDiagnosticHandler();
231 
232  /// \brief Return if a code hotness metric should be included in optimization
233  /// diagnostics.
234  bool getDiagnosticsHotnessRequested() const;
235  /// \brief Set if a code hotness metric should be included in optimization
236  /// diagnostics.
237  void setDiagnosticsHotnessRequested(bool Requested);
238 
239  /// \brief Return the minimum hotness value a diagnostic would need in order
240  /// to be included in optimization diagnostics. If there is no minimum, this
241  /// returns None.
242  uint64_t getDiagnosticsHotnessThreshold() const;
243 
244  /// \brief Set the minimum hotness value a diagnostic needs in order to be
245  /// included in optimization diagnostics.
246  void setDiagnosticsHotnessThreshold(uint64_t Threshold);
247 
248  /// \brief Return the YAML file used by the backend to save optimization
249  /// diagnostics. If null, diagnostics are not saved in a file but only
250  /// emitted via the diagnostic handler.
251  yaml::Output *getDiagnosticsOutputFile();
252  /// Set the diagnostics output file used for optimization diagnostics.
253  ///
254  /// By default or if invoked with null, diagnostics are not saved in a file
255  /// but only emitted via the diagnostic handler. Even if an output file is
256  /// set, the handler is invoked for each diagnostic message.
257  void setDiagnosticsOutputFile(std::unique_ptr<yaml::Output> F);
258 
259  /// \brief Get the prefix that should be printed in front of a diagnostic of
260  /// the given \p Severity
261  static const char *getDiagnosticMessagePrefix(DiagnosticSeverity Severity);
262 
263  /// \brief Report a message to the currently installed diagnostic handler.
264  ///
265  /// This function returns, in particular in the case of error reporting
266  /// (DI.Severity == \a DS_Error), so the caller should leave the compilation
267  /// process in a self-consistent state, even though the generated code
268  /// need not be correct.
269  ///
270  /// The diagnostic message will be implicitly prefixed with a severity keyword
271  /// according to \p DI.getSeverity(), i.e., "error: " for \a DS_Error,
272  /// "warning: " for \a DS_Warning, and "note: " for \a DS_Note.
273  void diagnose(const DiagnosticInfo &DI);
274 
275  /// \brief Registers a yield callback with the given context.
276  ///
277  /// The yield callback function may be called by LLVM to transfer control back
278  /// to the client that invoked the LLVM compilation. This can be used to yield
279  /// control of the thread, or perform periodic work needed by the client.
280  /// There is no guaranteed frequency at which callbacks must occur; in fact,
281  /// the client is not guaranteed to ever receive this callback. It is at the
282  /// sole discretion of LLVM to do so and only if it can guarantee that
283  /// suspending the thread won't block any forward progress in other LLVM
284  /// contexts in the same process.
285  ///
286  /// At a suspend point, the state of the current LLVM context is intentionally
287  /// undefined. No assumptions about it can or should be made. Only LLVM
288  /// context API calls that explicitly state that they can be used during a
289  /// yield callback are allowed to be used. Any other API calls into the
290  /// context are not supported until the yield callback function returns
291  /// control to LLVM. Other LLVM contexts are unaffected by this restriction.
292  void setYieldCallback(YieldCallbackTy Callback, void *OpaqueHandle);
293 
294  /// \brief Calls the yield callback (if applicable).
295  ///
296  /// This transfers control of the current thread back to the client, which may
297  /// suspend the current thread. Only call this method when LLVM doesn't hold
298  /// any global mutex or cannot block the execution in another LLVM context.
299  void yield();
300 
301  /// emitError - Emit an error message to the currently installed error handler
302  /// with optional location information. This function returns, so code should
303  /// be prepared to drop the erroneous construct on the floor and "not crash".
304  /// The generated code need not be correct. The error message will be
305  /// implicitly prefixed with "error: " and should not end with a ".".
306  void emitError(unsigned LocCookie, const Twine &ErrorStr);
307  void emitError(const Instruction *I, const Twine &ErrorStr);
308  void emitError(const Twine &ErrorStr);
309 
310  /// \brief Query for a debug option's value.
311  ///
312  /// This function returns typed data populated from command line parsing.
313  template <typename ValT, typename Base, ValT(Base::*Mem)>
314  ValT getOption() const {
315  return OptionRegistry::instance().template get<ValT, Base, Mem>();
316  }
317 
318  /// \brief Access the object which manages optimization bisection for failure
319  /// analysis.
320  OptBisect &getOptBisect();
321 private:
322  // Module needs access to the add/removeModule methods.
323  friend class Module;
324 
325  /// addModule - Register a module as being instantiated in this context. If
326  /// the context is deleted, the module will be deleted as well.
327  void addModule(Module*);
328 
329  /// removeModule - Unregister a module from this context.
330  void removeModule(Module*);
331 };
332 
333 // Create wrappers for C Binding types (see CBindingWrapping.h).
335 
336 /* Specialized opaque context conversions.
337  */
339  return reinterpret_cast<LLVMContext**>(Tys);
340 }
341 
342 inline LLVMContextRef *wrap(const LLVMContext **Tys) {
343  return reinterpret_cast<LLVMContextRef*>(const_cast<LLVMContext**>(Tys));
344 }
345 
346 } // end namespace llvm
347 
348 #endif // LLVM_IR_LLVMCONTEXT_H
This is the base class for diagnostic handling in LLVM.
LLVMContext & Context
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:63
void(*)(LLVMContext *Context, void *OpaqueHandle) YieldCallbackTy
Defines the type of a yield callback.
Definition: LLVMContext.h:175
F(f)
DiagnosticSeverity
Defines the different supported severity of a diagnostic.
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
Attribute unwrap(LLVMAttributeRef Attr)
Definition: Attributes.h:195
static OptionRegistry & instance()
Returns a reference to the singleton instance.
Definition: Options.cpp:33
struct LLVMOpaqueContext * LLVMContextRef
The top-level container for all LLVM global data.
Definition: Types.h:54
void(*)(const DiagnosticInfo &DI, void *Context) DiagnosticHandlerTy
This class implements a mechanism to disable passes and individual optimizations at compile time base...
Definition: OptBisect.h:28
This is the base abstract class for diagnostic reporting in the backend.
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:69
amdgpu inline
The Output class is used to generate a yaml document from in-memory structs and vectors.
Definition: YAMLTraits.h:1260
DEFINE_SIMPLE_CONVERSION_FUNCTIONS(std::shared_ptr< Module >, LLVMSharedModuleRef) namespace detail
LLVMContextImpl *const pImpl
Definition: LLVMContext.h:71
Synchronized with respect to all concurrently executing threads.
Definition: LLVMContext.h:59
ValT getOption() const
Query for a debug option&#39;s value.
Definition: LLVMContext.h:314
This file declares helper objects for defining debug options that can be configured via the command l...
void(*)(const SMDiagnostic &, void *Context, unsigned LocCookie) InlineAsmDiagHandlerTy
Definition: LLVMContext.h:171
Synchronized with respect to signal handlers executing in the same thread.
Definition: LLVMContext.h:56
LLVMAttributeRef wrap(Attribute Attr)
Definition: Attributes.h:190
#define I(x, y, z)
Definition: MD5.cpp:58
static int const Threshold
TODO: Write a new FunctionPass AliasAnalysis so that it can keep a cache.
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
Instances of this class encapsulate one diagnostic report, allowing printing to a raw_ostream as a ca...
Definition: SourceMgr.h:233