LLVM  3.7.0
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/Core.h"
20 #include "llvm/Support/Compiler.h"
21 #include "llvm/Support/Options.h"
22 
23 namespace llvm {
24 
25 class LLVMContextImpl;
26 class StringRef;
27 class Twine;
28 class Instruction;
29 class Module;
30 class SMDiagnostic;
31 class DiagnosticInfo;
32 template <typename T> class SmallVectorImpl;
33 class Function;
34 class DebugLoc;
35 
36 /// This is an important class for using LLVM in a threaded context. It
37 /// (opaquely) owns and manages the core "global" data of LLVM's core
38 /// infrastructure, including the type and constant uniquing tables.
39 /// LLVMContext itself provides no locking guarantees, so you should be careful
40 /// to have one context per thread.
41 class LLVMContext {
42 public:
44  LLVMContext();
45  ~LLVMContext();
46 
47  // Pinned metadata names, which always have the same value. This is a
48  // compile-time performance optimization, not a correctness optimization.
49  enum {
50  MD_dbg = 0, // "dbg"
51  MD_tbaa = 1, // "tbaa"
52  MD_prof = 2, // "prof"
53  MD_fpmath = 3, // "fpmath"
54  MD_range = 4, // "range"
55  MD_tbaa_struct = 5, // "tbaa.struct"
56  MD_invariant_load = 6, // "invariant.load"
57  MD_alias_scope = 7, // "alias.scope"
58  MD_noalias = 8, // "noalias",
59  MD_nontemporal = 9, // "nontemporal"
60  MD_mem_parallel_loop_access = 10, // "llvm.mem.parallel_loop_access"
61  MD_nonnull = 11, // "nonnull"
62  MD_dereferenceable = 12, // "dereferenceable"
63  MD_dereferenceable_or_null = 13 // "dereferenceable_or_null"
64  };
65 
66  /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
67  /// This ID is uniqued across modules in the current LLVMContext.
68  unsigned getMDKindID(StringRef Name) const;
69 
70  /// getMDKindNames - Populate client supplied SmallVector with the name for
71  /// custom metadata IDs registered in this LLVMContext.
72  void getMDKindNames(SmallVectorImpl<StringRef> &Result) const;
73 
74 
75  typedef void (*InlineAsmDiagHandlerTy)(const SMDiagnostic&, void *Context,
76  unsigned LocCookie);
77 
78  /// Defines the type of a diagnostic handler.
79  /// \see LLVMContext::setDiagnosticHandler.
80  /// \see LLVMContext::diagnose.
81  typedef void (*DiagnosticHandlerTy)(const DiagnosticInfo &DI, void *Context);
82 
83  /// Defines the type of a yield callback.
84  /// \see LLVMContext::setYieldCallback.
85  typedef void (*YieldCallbackTy)(LLVMContext *Context, void *OpaqueHandle);
86 
87  /// setInlineAsmDiagnosticHandler - This method sets a handler that is invoked
88  /// when problems with inline asm are detected by the backend. The first
89  /// argument is a function pointer and the second is a context pointer that
90  /// gets passed into the DiagHandler.
91  ///
92  /// LLVMContext doesn't take ownership or interpret either of these
93  /// pointers.
95  void *DiagContext = nullptr);
96 
97  /// getInlineAsmDiagnosticHandler - Return the diagnostic handler set by
98  /// setInlineAsmDiagnosticHandler.
100 
101  /// getInlineAsmDiagnosticContext - Return the diagnostic context set by
102  /// setInlineAsmDiagnosticHandler.
103  void *getInlineAsmDiagnosticContext() const;
104 
105  /// setDiagnosticHandler - This method sets a handler that is invoked
106  /// when the backend needs to report anything to the user. The first
107  /// argument is a function pointer and the second is a context pointer that
108  /// gets passed into the DiagHandler. The third argument should be set to
109  /// true if the handler only expects enabled diagnostics.
110  ///
111  /// LLVMContext doesn't take ownership or interpret either of these
112  /// pointers.
113  void setDiagnosticHandler(DiagnosticHandlerTy DiagHandler,
114  void *DiagContext = nullptr,
115  bool RespectFilters = false);
116 
117  /// getDiagnosticHandler - Return the diagnostic handler set by
118  /// setDiagnosticHandler.
120 
121  /// getDiagnosticContext - Return the diagnostic context set by
122  /// setDiagnosticContext.
123  void *getDiagnosticContext() const;
124 
125  /// \brief Report a message to the currently installed diagnostic handler.
126  ///
127  /// This function returns, in particular in the case of error reporting
128  /// (DI.Severity == \a DS_Error), so the caller should leave the compilation
129  /// process in a self-consistent state, even though the generated code
130  /// need not be correct.
131  ///
132  /// The diagnostic message will be implicitly prefixed with a severity keyword
133  /// according to \p DI.getSeverity(), i.e., "error: " for \a DS_Error,
134  /// "warning: " for \a DS_Warning, and "note: " for \a DS_Note.
135  void diagnose(const DiagnosticInfo &DI);
136 
137  /// \brief Registers a yield callback with the given context.
138  ///
139  /// The yield callback function may be called by LLVM to transfer control back
140  /// to the client that invoked the LLVM compilation. This can be used to yield
141  /// control of the thread, or perform periodic work needed by the client.
142  /// There is no guaranteed frequency at which callbacks must occur; in fact,
143  /// the client is not guaranteed to ever receive this callback. It is at the
144  /// sole discretion of LLVM to do so and only if it can guarantee that
145  /// suspending the thread won't block any forward progress in other LLVM
146  /// contexts in the same process.
147  ///
148  /// At a suspend point, the state of the current LLVM context is intentionally
149  /// undefined. No assumptions about it can or should be made. Only LLVM
150  /// context API calls that explicitly state that they can be used during a
151  /// yield callback are allowed to be used. Any other API calls into the
152  /// context are not supported until the yield callback function returns
153  /// control to LLVM. Other LLVM contexts are unaffected by this restriction.
154  void setYieldCallback(YieldCallbackTy Callback, void *OpaqueHandle);
155 
156  /// \brief Calls the yield callback (if applicable).
157  ///
158  /// This transfers control of the current thread back to the client, which may
159  /// suspend the current thread. Only call this method when LLVM doesn't hold
160  /// any global mutex or cannot block the execution in another LLVM context.
161  void yield();
162 
163  /// emitError - Emit an error message to the currently installed error handler
164  /// with optional location information. This function returns, so code should
165  /// be prepared to drop the erroneous construct on the floor and "not crash".
166  /// The generated code need not be correct. The error message will be
167  /// implicitly prefixed with "error: " and should not end with a ".".
168  void emitError(unsigned LocCookie, const Twine &ErrorStr);
169  void emitError(const Instruction *I, const Twine &ErrorStr);
170  void emitError(const Twine &ErrorStr);
171 
172  /// \brief Query for a debug option's value.
173  ///
174  /// This function returns typed data populated from command line parsing.
175  template <typename ValT, typename Base, ValT(Base::*Mem)>
176  ValT getOption() const {
177  return OptionRegistry::instance().template get<ValT, Base, Mem>();
178  }
179 
180 private:
181  LLVMContext(LLVMContext&) = delete;
182  void operator=(LLVMContext&) = delete;
183 
184  /// addModule - Register a module as being instantiated in this context. If
185  /// the context is deleted, the module will be deleted as well.
186  void addModule(Module*);
187 
188  /// removeModule - Unregister a module from this context.
189  void removeModule(Module*);
190 
191  // Module needs access to the add/removeModule methods.
192  friend class Module;
193 };
194 
195 /// getGlobalContext - Returns a global context. This is for LLVM clients that
196 /// only care about operating on a single thread.
197 extern LLVMContext &getGlobalContext();
198 
199 // Create wrappers for C Binding types (see CBindingWrapping.h).
201 
202 /* Specialized opaque context conversions.
203  */
205  return reinterpret_cast<LLVMContext**>(Tys);
206 }
207 
208 inline LLVMContextRef *wrap(const LLVMContext **Tys) {
209  return reinterpret_cast<LLVMContextRef*>(const_cast<LLVMContext**>(Tys));
210 }
211 
212 }
213 
214 #endif
InlineAsmDiagHandlerTy getInlineAsmDiagnosticHandler() const
getInlineAsmDiagnosticHandler - Return the diagnostic handler set by setInlineAsmDiagnosticHandler.
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:114
void(* DiagnosticHandlerTy)(const DiagnosticInfo &DI, void *Context)
Defines the type of a diagnostic handler.
Definition: LLVMContext.h:81
DiagnosticHandlerTy getDiagnosticHandler() const
getDiagnosticHandler - Return the diagnostic handler set by setDiagnosticHandler. ...
void setInlineAsmDiagnosticHandler(InlineAsmDiagHandlerTy DiagHandler, void *DiagContext=nullptr)
setInlineAsmDiagnosticHandler - This method sets a handler that is invoked when problems with inline ...
void setYieldCallback(YieldCallbackTy Callback, void *OpaqueHandle)
Registers a yield callback with the given context.
void yield()
Calls the yield callback (if applicable).
#define DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ty, ref)
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:79
void emitError(unsigned LocCookie, const Twine &ErrorStr)
emitError - Emit an error message to the currently installed error handler with optional location inf...
LLVMTargetDataRef wrap(const DataLayout *P)
Definition: DataLayout.h:469
static OptionRegistry & instance()
Returns a reference to the singleton instance.
Definition: Options.cpp:33
void getMDKindNames(SmallVectorImpl< StringRef > &Result) const
getMDKindNames - Populate client supplied SmallVector with the name for custom metadata IDs registere...
always inline
DataLayout * unwrap(LLVMTargetDataRef P)
Definition: DataLayout.h:465
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:41
struct LLVMOpaqueContext * LLVMContextRef
The top-level container for all LLVM global data.
Definition: Core.h:70
ValT getOption() const
Query for a debug option's value.
Definition: LLVMContext.h:176
unsigned getMDKindID(StringRef Name) const
getMDKindID - Return a unique non-zero ID for the specified metadata kind.
void * getDiagnosticContext() const
getDiagnosticContext - Return the diagnostic context set by setDiagnosticContext. ...
LLVMContextImpl *const pImpl
Definition: LLVMContext.h:43
This file declares helper objects for defining debug options that can be configured via the command l...
void(* InlineAsmDiagHandlerTy)(const SMDiagnostic &, void *Context, unsigned LocCookie)
Definition: LLVMContext.h:75
void * getInlineAsmDiagnosticContext() const
getInlineAsmDiagnosticContext - Return the diagnostic context set by setInlineAsmDiagnosticHandler.
#define I(x, y, z)
Definition: MD5.cpp:54
void diagnose(const DiagnosticInfo &DI)
Report a message to the currently installed diagnostic handler.
void setDiagnosticHandler(DiagnosticHandlerTy DiagHandler, void *DiagContext=nullptr, bool RespectFilters=false)
setDiagnosticHandler - This method sets a handler that is invoked when the backend needs to report an...
void(* YieldCallbackTy)(LLVMContext *Context, void *OpaqueHandle)
Defines the type of a yield callback.
Definition: LLVMContext.h:85
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:40
LLVMContext & getGlobalContext()
getGlobalContext - Returns a global context.
Definition: LLVMContext.cpp:30
Instances of this class encapsulate one diagnostic report, allowing printing to a raw_ostream as a ca...
Definition: SourceMgr.h:233