1 //===-- llvm/Module.h - C++ class to represent a VM module ------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// Module.h This file contains the declarations for the Module class.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_IR_MODULE_H
16 #define LLVM_IR_MODULE_H
18 #include "llvm/ADT/iterator_range.h"
19 #include "llvm/IR/DataLayout.h"
20 #include "llvm/IR/Function.h"
21 #include "llvm/IR/GlobalAlias.h"
22 #include "llvm/IR/GlobalVariable.h"
23 #include "llvm/IR/Metadata.h"
24 #include "llvm/Support/CBindingWrapping.h"
25 #include "llvm/Support/DataTypes.h"
26 #include <system_error>
33 template<typename T> struct DenseMapInfo;
34 template<typename KeyT, typename ValueT, typename KeyInfoT> class DenseMap;
36 template<> struct ilist_traits<Function>
37 : public SymbolTableListTraits<Function, Module> {
39 // createSentinel is used to get hold of the node that marks the end of the
40 // list... (same trick used here as in ilist_traits<Instruction>)
41 Function *createSentinel() const {
42 return static_cast<Function*>(&Sentinel);
44 static void destroySentinel(Function*) {}
46 Function *provideInitialHead() const { return createSentinel(); }
47 Function *ensureHead(Function*) const { return createSentinel(); }
48 static void noteHead(Function*, Function*) {}
51 mutable ilist_node<Function> Sentinel;
54 template<> struct ilist_traits<GlobalVariable>
55 : public SymbolTableListTraits<GlobalVariable, Module> {
56 // createSentinel is used to create a node that marks the end of the list.
57 GlobalVariable *createSentinel() const {
58 return static_cast<GlobalVariable*>(&Sentinel);
60 static void destroySentinel(GlobalVariable*) {}
62 GlobalVariable *provideInitialHead() const { return createSentinel(); }
63 GlobalVariable *ensureHead(GlobalVariable*) const { return createSentinel(); }
64 static void noteHead(GlobalVariable*, GlobalVariable*) {}
66 mutable ilist_node<GlobalVariable> Sentinel;
69 template<> struct ilist_traits<GlobalAlias>
70 : public SymbolTableListTraits<GlobalAlias, Module> {
71 // createSentinel is used to create a node that marks the end of the list.
72 GlobalAlias *createSentinel() const {
73 return static_cast<GlobalAlias*>(&Sentinel);
75 static void destroySentinel(GlobalAlias*) {}
77 GlobalAlias *provideInitialHead() const { return createSentinel(); }
78 GlobalAlias *ensureHead(GlobalAlias*) const { return createSentinel(); }
79 static void noteHead(GlobalAlias*, GlobalAlias*) {}
81 mutable ilist_node<GlobalAlias> Sentinel;
84 template<> struct ilist_traits<NamedMDNode>
85 : public ilist_default_traits<NamedMDNode> {
86 // createSentinel is used to get hold of a node that marks the end of
88 NamedMDNode *createSentinel() const {
89 return static_cast<NamedMDNode*>(&Sentinel);
91 static void destroySentinel(NamedMDNode*) {}
93 NamedMDNode *provideInitialHead() const { return createSentinel(); }
94 NamedMDNode *ensureHead(NamedMDNode*) const { return createSentinel(); }
95 static void noteHead(NamedMDNode*, NamedMDNode*) {}
96 void addNodeToList(NamedMDNode *) {}
97 void removeNodeFromList(NamedMDNode *) {}
99 mutable ilist_node<NamedMDNode> Sentinel;
102 /// A Module instance is used to store all the information related to an
103 /// LLVM module. Modules are the top level container of all other LLVM
104 /// Intermediate Representation (IR) objects. Each module directly contains a
105 /// list of globals variables, a list of functions, a list of libraries (or
106 /// other modules) this module depends on, a symbol table, and various data
107 /// about the target's characteristics.
109 /// A module maintains a GlobalValRefMap object that is used to hold all
110 /// constant references to global variables in the module. When a global
111 /// variable is destroyed, it should have no entries in the GlobalValueRefMap.
112 /// @brief The main container class for the LLVM Intermediate Representation.
114 /// @name Types And Enumerations
117 /// The type for the list of global variables.
118 typedef iplist<GlobalVariable> GlobalListType;
119 /// The type for the list of functions.
120 typedef iplist<Function> FunctionListType;
121 /// The type for the list of aliases.
122 typedef iplist<GlobalAlias> AliasListType;
123 /// The type for the list of named metadata.
124 typedef ilist<NamedMDNode> NamedMDListType;
126 /// The Global Variable iterator.
127 typedef GlobalListType::iterator global_iterator;
128 /// The Global Variable constant iterator.
129 typedef GlobalListType::const_iterator const_global_iterator;
131 /// The Function iterators.
132 typedef FunctionListType::iterator iterator;
133 /// The Function constant iterator
134 typedef FunctionListType::const_iterator const_iterator;
136 /// The Global Alias iterators.
137 typedef AliasListType::iterator alias_iterator;
138 /// The Global Alias constant iterator
139 typedef AliasListType::const_iterator const_alias_iterator;
141 /// The named metadata iterators.
142 typedef NamedMDListType::iterator named_metadata_iterator;
143 /// The named metadata constant interators.
144 typedef NamedMDListType::const_iterator const_named_metadata_iterator;
146 /// This enumeration defines the supported behaviors of module flags.
147 enum ModFlagBehavior {
148 /// Emits an error if two values disagree, otherwise the resulting value is
149 /// that of the operands.
152 /// Emits a warning if two values disagree. The result value will be the
153 /// operand for the flag from the first module being linked.
156 /// Adds a requirement that another module flag be present and have a
157 /// specified value after linking is performed. The value must be a metadata
158 /// pair, where the first element of the pair is the ID of the module flag
159 /// to be restricted, and the second element of the pair is the value the
160 /// module flag should be restricted to. This behavior can be used to
161 /// restrict the allowable results (via triggering of an error) of linking
162 /// IDs with the **Override** behavior.
165 /// Uses the specified value, regardless of the behavior or value of the
166 /// other module. If both modules specify **Override**, but the values
167 /// differ, an error will be emitted.
170 /// Appends the two values, which are required to be metadata nodes.
173 /// Appends the two values, which are required to be metadata
174 /// nodes. However, duplicate entries in the second list are dropped
175 /// during the append operation.
179 struct ModuleFlagEntry {
180 ModFlagBehavior Behavior;
183 ModuleFlagEntry(ModFlagBehavior B, MDString *K, Value *V)
184 : Behavior(B), Key(K), Val(V) {}
188 /// @name Member Variables
191 LLVMContext &Context; ///< The LLVMContext from which types and
192 ///< constants are allocated.
193 GlobalListType GlobalList; ///< The Global Variables in the module
194 FunctionListType FunctionList; ///< The Functions in the module
195 AliasListType AliasList; ///< The Aliases in the module
196 NamedMDListType NamedMDList; ///< The named metadata in the module
197 std::string GlobalScopeAsm; ///< Inline Asm at global scope.
198 ValueSymbolTable *ValSymTab; ///< Symbol table for values
199 std::unique_ptr<GVMaterializer>
200 Materializer; ///< Used to materialize GlobalValues
201 std::string ModuleID; ///< Human readable identifier for the module
202 std::string TargetTriple; ///< Platform target triple Module compiled on
203 void *NamedMDSymTab; ///< NamedMDNode names.
205 // We need to keep the string because the C API expects us to own the string
207 // Since we have it, we also use an empty string to represent a module without
208 // a DataLayout. If it has a DataLayout, these variables are in sync and the
209 // string is just a cache of getDataLayout()->getStringRepresentation().
210 std::string DataLayoutStr;
213 friend class Constant;
216 /// @name Constructors
219 /// The Module constructor. Note that there is no default constructor. You
220 /// must provide a name for the module upon construction.
221 explicit Module(StringRef ModuleID, LLVMContext& C);
222 /// The module destructor. This will dropAllReferences.
226 /// @name Module Level Accessors
229 /// Get the module identifier which is, essentially, the name of the module.
230 /// @returns the module identifier as a string
231 const std::string &getModuleIdentifier() const { return ModuleID; }
233 /// Get the data layout string for the module's target platform. This is
234 /// equivalent to getDataLayout()->getStringRepresentation().
235 const std::string &getDataLayoutStr() const { return DataLayoutStr; }
237 /// Get the data layout for the module's target platform.
238 const DataLayout *getDataLayout() const;
240 /// Get the target triple which is a string describing the target host.
241 /// @returns a string containing the target triple.
242 const std::string &getTargetTriple() const { return TargetTriple; }
244 /// Get the global data context.
245 /// @returns LLVMContext - a container for LLVM's global information
246 LLVMContext &getContext() const { return Context; }
248 /// Get any module-scope inline assembly blocks.
249 /// @returns a string containing the module-scope inline assembly blocks.
250 const std::string &getModuleInlineAsm() const { return GlobalScopeAsm; }
253 /// @name Module Level Mutators
256 /// Set the module identifier.
257 void setModuleIdentifier(StringRef ID) { ModuleID = ID; }
259 /// Set the data layout
260 void setDataLayout(StringRef Desc);
261 void setDataLayout(const DataLayout *Other);
263 /// Set the target triple.
264 void setTargetTriple(StringRef T) { TargetTriple = T; }
266 /// Set the module-scope inline assembly blocks.
267 void setModuleInlineAsm(StringRef Asm) {
268 GlobalScopeAsm = Asm;
269 if (!GlobalScopeAsm.empty() &&
270 GlobalScopeAsm[GlobalScopeAsm.size()-1] != '\n')
271 GlobalScopeAsm += '\n';
274 /// Append to the module-scope inline assembly blocks, automatically inserting
275 /// a separating newline if necessary.
276 void appendModuleInlineAsm(StringRef Asm) {
277 GlobalScopeAsm += Asm;
278 if (!GlobalScopeAsm.empty() &&
279 GlobalScopeAsm[GlobalScopeAsm.size()-1] != '\n')
280 GlobalScopeAsm += '\n';
284 /// @name Generic Value Accessors
287 /// Return the global value in the module with the specified name, of
288 /// arbitrary type. This method returns null if a global with the specified
289 /// name is not found.
290 GlobalValue *getNamedValue(StringRef Name) const;
292 /// Return a unique non-zero ID for the specified metadata kind. This ID is
293 /// uniqued across modules in the current LLVMContext.
294 unsigned getMDKindID(StringRef Name) const;
296 /// Populate client supplied SmallVector with the name for custom metadata IDs
297 /// registered in this LLVMContext.
298 void getMDKindNames(SmallVectorImpl<StringRef> &Result) const;
300 /// Return the type with the specified name, or null if there is none by that
302 StructType *getTypeByName(StringRef Name) const;
305 /// @name Function Accessors
308 /// Look up the specified function in the module symbol table. Four
310 /// 1. If it does not exist, add a prototype for the function and return it.
311 /// 2. If it exists, and has a local linkage, the existing function is
312 /// renamed and a new one is inserted.
313 /// 3. Otherwise, if the existing function has the correct prototype, return
314 /// the existing function.
315 /// 4. Finally, the function exists but has the wrong prototype: return the
316 /// function with a constantexpr cast to the right prototype.
317 Constant *getOrInsertFunction(StringRef Name, FunctionType *T,
318 AttributeSet AttributeList);
320 Constant *getOrInsertFunction(StringRef Name, FunctionType *T);
322 /// Look up the specified function in the module symbol table. If it does not
323 /// exist, add a prototype for the function and return it. This function
324 /// guarantees to return a constant of pointer to the specified function type
325 /// or a ConstantExpr BitCast of that type if the named function has a
326 /// different type. This version of the method takes a null terminated list of
327 /// function arguments, which makes it easier for clients to use.
328 Constant *getOrInsertFunction(StringRef Name,
329 AttributeSet AttributeList,
330 Type *RetTy, ...) END_WITH_NULL;
332 /// Same as above, but without the attributes.
333 Constant *getOrInsertFunction(StringRef Name, Type *RetTy, ...)
336 /// Look up the specified function in the module symbol table. If it does not
337 /// exist, return null.
338 Function *getFunction(StringRef Name) const;
341 /// @name Global Variable Accessors
344 /// Look up the specified global variable in the module symbol table. If it
345 /// does not exist, return null. If AllowInternal is set to true, this
346 /// function will return types that have InternalLinkage. By default, these
347 /// types are not returned.
348 const GlobalVariable *getGlobalVariable(StringRef Name,
349 bool AllowInternal = false) const {
350 return const_cast<Module *>(this)->getGlobalVariable(Name, AllowInternal);
353 GlobalVariable *getGlobalVariable(StringRef Name, bool AllowInternal = false);
355 /// Return the global variable in the module with the specified name, of
356 /// arbitrary type. This method returns null if a global with the specified
357 /// name is not found.
358 GlobalVariable *getNamedGlobal(StringRef Name) {
359 return getGlobalVariable(Name, true);
361 const GlobalVariable *getNamedGlobal(StringRef Name) const {
362 return const_cast<Module *>(this)->getNamedGlobal(Name);
365 /// Look up the specified global in the module symbol table.
366 /// 1. If it does not exist, add a declaration of the global and return it.
367 /// 2. Else, the global exists but has the wrong type: return the function
368 /// with a constantexpr cast to the right type.
369 /// 3. Finally, if the existing global is the correct declaration, return
370 /// the existing global.
371 Constant *getOrInsertGlobal(StringRef Name, Type *Ty);
374 /// @name Global Alias Accessors
377 /// Return the global alias in the module with the specified name, of
378 /// arbitrary type. This method returns null if a global with the specified
379 /// name is not found.
380 GlobalAlias *getNamedAlias(StringRef Name) const;
383 /// @name Named Metadata Accessors
386 /// Return the first NamedMDNode in the module with the specified name. This
387 /// method returns null if a NamedMDNode with the specified name is not found.
388 NamedMDNode *getNamedMetadata(const Twine &Name) const;
390 /// Return the named MDNode in the module with the specified name. This method
391 /// returns a new NamedMDNode if a NamedMDNode with the specified name is not
393 NamedMDNode *getOrInsertNamedMetadata(StringRef Name);
395 /// Remove the given NamedMDNode from this module and delete it.
396 void eraseNamedMetadata(NamedMDNode *NMD);
399 /// @name Module Flags Accessors
402 /// Returns the module flags in the provided vector.
403 void getModuleFlagsMetadata(SmallVectorImpl<ModuleFlagEntry> &Flags) const;
405 /// Return the corresponding value if Key appears in module flags, otherwise
407 Value *getModuleFlag(StringRef Key) const;
409 /// Returns the NamedMDNode in the module that represents module-level flags.
410 /// This method returns null if there are no module-level flags.
411 NamedMDNode *getModuleFlagsMetadata() const;
413 /// Returns the NamedMDNode in the module that represents module-level flags.
414 /// If module-level flags aren't found, it creates the named metadata that
416 NamedMDNode *getOrInsertModuleFlagsMetadata();
418 /// Add a module-level flag to the module-level flags metadata. It will create
419 /// the module-level flags named metadata if it doesn't already exist.
420 void addModuleFlag(ModFlagBehavior Behavior, StringRef Key, Value *Val);
421 void addModuleFlag(ModFlagBehavior Behavior, StringRef Key, uint32_t Val);
422 void addModuleFlag(MDNode *Node);
425 /// @name Materialization
428 /// Sets the GVMaterializer to GVM. This module must not yet have a
429 /// Materializer. To reset the materializer for a module that already has one,
430 /// call MaterializeAllPermanently first. Destroying this module will destroy
431 /// its materializer without materializing any more GlobalValues. Without
432 /// destroying the Module, there is no way to detach or destroy a materializer
433 /// without materializing all the GVs it controls, to avoid leaving orphan
434 /// unmaterialized GVs.
435 void setMaterializer(GVMaterializer *GVM);
436 /// Retrieves the GVMaterializer, if any, for this Module.
437 GVMaterializer *getMaterializer() const { return Materializer.get(); }
439 /// True if the definition of GV has yet to be materializedfrom the
441 bool isMaterializable(const GlobalValue *GV) const;
442 /// Returns true if this GV was loaded from this Module's GVMaterializer and
443 /// the GVMaterializer knows how to dematerialize the GV.
444 bool isDematerializable(const GlobalValue *GV) const;
446 /// Make sure the GlobalValue is fully read. If the module is corrupt, this
447 /// returns true and fills in the optional string with information about the
448 /// problem. If successful, this returns false.
449 bool Materialize(GlobalValue *GV, std::string *ErrInfo = nullptr);
450 /// If the GlobalValue is read in, and if the GVMaterializer supports it,
451 /// release the memory for the function, and set it up to be materialized
452 /// lazily. If !isDematerializable(), this method is a noop.
453 void Dematerialize(GlobalValue *GV);
455 /// Make sure all GlobalValues in this Module are fully read.
456 std::error_code materializeAll();
458 /// Make sure all GlobalValues in this Module are fully read and clear the
459 /// Materializer. If the module is corrupt, this DOES NOT clear the old
461 std::error_code materializeAllPermanently();
464 /// @name Direct access to the globals list, functions list, and symbol table
467 /// Get the Module's list of global variables (constant).
468 const GlobalListType &getGlobalList() const { return GlobalList; }
469 /// Get the Module's list of global variables.
470 GlobalListType &getGlobalList() { return GlobalList; }
471 static iplist<GlobalVariable> Module::*getSublistAccess(GlobalVariable*) {
472 return &Module::GlobalList;
474 /// Get the Module's list of functions (constant).
475 const FunctionListType &getFunctionList() const { return FunctionList; }
476 /// Get the Module's list of functions.
477 FunctionListType &getFunctionList() { return FunctionList; }
478 static iplist<Function> Module::*getSublistAccess(Function*) {
479 return &Module::FunctionList;
481 /// Get the Module's list of aliases (constant).
482 const AliasListType &getAliasList() const { return AliasList; }
483 /// Get the Module's list of aliases.
484 AliasListType &getAliasList() { return AliasList; }
485 static iplist<GlobalAlias> Module::*getSublistAccess(GlobalAlias*) {
486 return &Module::AliasList;
488 /// Get the Module's list of named metadata (constant).
489 const NamedMDListType &getNamedMDList() const { return NamedMDList; }
490 /// Get the Module's list of named metadata.
491 NamedMDListType &getNamedMDList() { return NamedMDList; }
492 static ilist<NamedMDNode> Module::*getSublistAccess(NamedMDNode*) {
493 return &Module::NamedMDList;
495 /// Get the symbol table of global variable and function identifiers
496 const ValueSymbolTable &getValueSymbolTable() const { return *ValSymTab; }
497 /// Get the Module's symbol table of global variable and function identifiers.
498 ValueSymbolTable &getValueSymbolTable() { return *ValSymTab; }
501 /// @name Global Variable Iteration
504 global_iterator global_begin() { return GlobalList.begin(); }
505 const_global_iterator global_begin() const { return GlobalList.begin(); }
506 global_iterator global_end () { return GlobalList.end(); }
507 const_global_iterator global_end () const { return GlobalList.end(); }
508 bool global_empty() const { return GlobalList.empty(); }
510 iterator_range<global_iterator> globals() {
511 return iterator_range<global_iterator>(global_begin(), global_end());
513 iterator_range<const_global_iterator> globals() const {
514 return iterator_range<const_global_iterator>(global_begin(), global_end());
518 /// @name Function Iteration
521 iterator begin() { return FunctionList.begin(); }
522 const_iterator begin() const { return FunctionList.begin(); }
523 iterator end () { return FunctionList.end(); }
524 const_iterator end () const { return FunctionList.end(); }
525 size_t size() const { return FunctionList.size(); }
526 bool empty() const { return FunctionList.empty(); }
529 /// @name Alias Iteration
532 alias_iterator alias_begin() { return AliasList.begin(); }
533 const_alias_iterator alias_begin() const { return AliasList.begin(); }
534 alias_iterator alias_end () { return AliasList.end(); }
535 const_alias_iterator alias_end () const { return AliasList.end(); }
536 size_t alias_size () const { return AliasList.size(); }
537 bool alias_empty() const { return AliasList.empty(); }
539 iterator_range<alias_iterator> aliases() {
540 return iterator_range<alias_iterator>(alias_begin(), alias_end());
542 iterator_range<const_alias_iterator> aliases() const {
543 return iterator_range<const_alias_iterator>(alias_begin(), alias_end());
547 /// @name Named Metadata Iteration
550 named_metadata_iterator named_metadata_begin() { return NamedMDList.begin(); }
551 const_named_metadata_iterator named_metadata_begin() const {
552 return NamedMDList.begin();
555 named_metadata_iterator named_metadata_end() { return NamedMDList.end(); }
556 const_named_metadata_iterator named_metadata_end() const {
557 return NamedMDList.end();
560 size_t named_metadata_size() const { return NamedMDList.size(); }
561 bool named_metadata_empty() const { return NamedMDList.empty(); }
563 iterator_range<named_metadata_iterator> named_metadata() {
564 return iterator_range<named_metadata_iterator>(named_metadata_begin(),
565 named_metadata_end());
567 iterator_range<const_named_metadata_iterator> named_metadata() const {
568 return iterator_range<const_named_metadata_iterator>(named_metadata_begin(),
569 named_metadata_end());
573 /// @name Utility functions for printing and dumping Module objects
576 /// Print the module to an output stream with an optional
577 /// AssemblyAnnotationWriter.
578 void print(raw_ostream &OS, AssemblyAnnotationWriter *AAW) const;
580 /// Dump the module to stderr (for debugging).
583 /// This function causes all the subinstructions to "let go" of all references
584 /// that they are maintaining. This allows one to 'delete' a whole class at
585 /// a time, even though there may be circular references... first all
586 /// references are dropped, and all use counts go to zero. Then everything
587 /// is delete'd for real. Note that no operations are valid on an object
588 /// that has "dropped all references", except operator delete.
589 void dropAllReferences();
592 /// @name Utility functions for querying Debug information.
595 /// \brief Returns the Dwarf Version by checking module flags.
596 unsigned getDwarfVersion() const;
601 /// An raw_ostream inserter for modules.
602 inline raw_ostream &operator<<(raw_ostream &O, const Module &M) {
607 // Create wrappers for C Binding types (see CBindingWrapping.h).
608 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(Module, LLVMModuleRef)
610 /* LLVMModuleProviderRef exists for historical reasons, but now just holds a
613 inline Module *unwrap(LLVMModuleProviderRef MP) {
614 return reinterpret_cast<Module*>(MP);
617 } // End llvm namespace