| //===- Identifier.h - MLIR Identifier Class ---------------------*- C++ -*-===// |
| // |
| // Part of the MLIR Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef MLIR_IR_IDENTIFIER_H |
| #define MLIR_IR_IDENTIFIER_H |
| |
| #include "mlir/Support/LLVM.h" |
| #include "llvm/ADT/DenseMapInfo.h" |
| #include "llvm/ADT/StringRef.h" |
| |
| namespace mlir { |
| class MLIRContext; |
| |
| /// This class represents a uniqued string owned by an MLIRContext. Strings |
| /// represented by this type cannot contain nul characters, and may not have a |
| /// zero length. |
| /// |
| /// This is a POD type with pointer size, so it should be passed around by |
| /// value. The underlying data is owned by MLIRContext and is thus immortal for |
| /// almost all clients. |
| class Identifier { |
| public: |
| /// Return an identifier for the specified string. |
| static Identifier get(StringRef str, MLIRContext *context); |
| Identifier(const Identifier &) = default; |
| Identifier &operator=(const Identifier &other) = default; |
| |
| /// Return a StringRef for the string. |
| StringRef strref() const { return StringRef(pointer, size()); } |
| |
| /// Identifiers implicitly convert to StringRefs. |
| operator StringRef() const { return strref(); } |
| |
| /// Return an std::string. |
| std::string str() const { return strref().str(); } |
| |
| /// Return a null terminated C string. |
| const char *c_str() const { return pointer; } |
| |
| /// Return a pointer to the start of the string data. |
| const char *data() const { return pointer; } |
| |
| /// Return the number of bytes in this string. |
| unsigned size() const { return ::strlen(pointer); } |
| |
| /// Return true if this identifier is the specified string. |
| bool is(StringRef string) const { return strref().equals(string); } |
| |
| const char *begin() const { return pointer; } |
| const char *end() const { return pointer + size(); } |
| |
| void print(raw_ostream &os) const; |
| void dump() const; |
| |
| const void *getAsOpaquePointer() const { |
| return static_cast<const void *>(pointer); |
| } |
| static Identifier getFromOpaquePointer(const void *pointer) { |
| return Identifier((const char *)pointer); |
| } |
| |
| private: |
| /// These are the bytes of the string, which is a nul terminated string. |
| const char *pointer; |
| explicit Identifier(const char *pointer) : pointer(pointer) {} |
| }; |
| |
| inline raw_ostream &operator<<(raw_ostream &os, Identifier identifier) { |
| identifier.print(os); |
| return os; |
| } |
| |
| inline bool operator==(Identifier lhs, Identifier rhs) { |
| return lhs.data() == rhs.data(); |
| } |
| |
| inline bool operator!=(Identifier lhs, Identifier rhs) { |
| return lhs.data() != rhs.data(); |
| } |
| |
| inline bool operator==(Identifier lhs, StringRef rhs) { return lhs.is(rhs); } |
| inline bool operator!=(Identifier lhs, StringRef rhs) { return !lhs.is(rhs); } |
| inline bool operator==(StringRef lhs, Identifier rhs) { return rhs.is(lhs); } |
| inline bool operator!=(StringRef lhs, Identifier rhs) { return !rhs.is(lhs); } |
| |
| // Make identifiers hashable. |
| inline llvm::hash_code hash_value(Identifier arg) { |
| return llvm::hash_value(arg.strref()); |
| } |
| |
| } // end namespace mlir |
| |
| namespace llvm { |
| // Identifiers hash just like pointers, there is no need to hash the bytes. |
| template <> |
| struct DenseMapInfo<mlir::Identifier> { |
| static mlir::Identifier getEmptyKey() { |
| auto pointer = llvm::DenseMapInfo<const void *>::getEmptyKey(); |
| return mlir::Identifier::getFromOpaquePointer(pointer); |
| } |
| static mlir::Identifier getTombstoneKey() { |
| auto pointer = llvm::DenseMapInfo<const void *>::getTombstoneKey(); |
| return mlir::Identifier::getFromOpaquePointer(pointer); |
| } |
| static unsigned getHashValue(mlir::Identifier Val) { |
| return DenseMapInfo<const void *>::getHashValue(Val.data()); |
| } |
| static bool isEqual(mlir::Identifier LHS, mlir::Identifier RHS) { |
| return LHS == RHS; |
| } |
| }; |
| |
| /// The pointer inside of an identifier comes from a StringMap, so its alignment |
| /// is always at least 4 and probably 8 (on 64-bit machines). Allow LLVM to |
| /// steal the low bits. |
| template <> |
| struct PointerLikeTypeTraits<mlir::Identifier> { |
| public: |
| static inline void *getAsVoidPointer(mlir::Identifier I) { |
| return const_cast<void *>(I.getAsOpaquePointer()); |
| } |
| static inline mlir::Identifier getFromVoidPointer(void *P) { |
| return mlir::Identifier::getFromOpaquePointer(P); |
| } |
| enum { NumLowBitsAvailable = 2 }; |
| }; |
| |
| } // end namespace llvm |
| #endif |