1 //===--- Source.h - Source location provider for the VM --------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // Defines a program which organises and links multiple bytecode functions. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_CLANG_AST_INTERP_SOURCE_H 14 #define LLVM_CLANG_AST_INTERP_SOURCE_H 15 16 #include "PrimType.h" 17 #include "clang/AST/DeclBase.h" 18 #include "clang/AST/Stmt.h" 19 #include "llvm/ADT/PointerUnion.h" 20 #include "llvm/Support/Endian.h" 21 22 namespace clang { 23 class Expr; 24 class SourceLocation; 25 class SourceRange; 26 namespace interp { 27 class Function; 28 29 /// Pointer into the code segment. 30 class CodePtr final { 31 public: 32 CodePtr() : Ptr(nullptr) {} 33 34 CodePtr &operator+=(int32_t Offset) { 35 Ptr += Offset; 36 return *this; 37 } 38 39 int32_t operator-(const CodePtr &RHS) const { 40 assert(Ptr != nullptr && RHS.Ptr != nullptr && "Invalid code pointer"); 41 return Ptr - RHS.Ptr; 42 } 43 44 CodePtr operator-(size_t RHS) const { 45 assert(Ptr != nullptr && "Invalid code pointer"); 46 return CodePtr(Ptr - RHS); 47 } 48 49 bool operator!=(const CodePtr &RHS) const { return Ptr != RHS.Ptr; } 50 const std::byte *operator*() const { return Ptr; } 51 52 operator bool() const { return Ptr; } 53 54 /// Reads data and advances the pointer. 55 template <typename T> std::enable_if_t<!std::is_pointer<T>::value, T> read() { 56 assert(aligned(Ptr)); 57 using namespace llvm::support; 58 T Value = endian::read<T, llvm::endianness::native>(Ptr); 59 Ptr += align(sizeof(T)); 60 return Value; 61 } 62 63 private: 64 friend class Function; 65 /// Constructor used by Function to generate pointers. 66 CodePtr(const std::byte *Ptr) : Ptr(Ptr) {} 67 /// Pointer into the code owned by a function. 68 const std::byte *Ptr; 69 }; 70 71 /// Describes the statement/declaration an opcode was generated from. 72 class SourceInfo final { 73 public: 74 SourceInfo() {} 75 SourceInfo(const Stmt *E) : Source(E) {} 76 SourceInfo(const Decl *D) : Source(D) {} 77 78 SourceLocation getLoc() const; 79 SourceRange getRange() const; 80 81 const Stmt *asStmt() const { return Source.dyn_cast<const Stmt *>(); } 82 const Decl *asDecl() const { return Source.dyn_cast<const Decl *>(); } 83 const Expr *asExpr() const; 84 85 operator bool() const { return !Source.isNull(); } 86 87 private: 88 llvm::PointerUnion<const Decl *, const Stmt *> Source; 89 }; 90 91 using SourceMap = std::vector<std::pair<unsigned, SourceInfo>>; 92 93 /// Interface for classes which map locations to sources. 94 class SourceMapper { 95 public: 96 virtual ~SourceMapper() {} 97 98 /// Returns source information for a given PC in a function. 99 virtual SourceInfo getSource(const Function *F, CodePtr PC) const = 0; 100 101 /// Returns the expression if an opcode belongs to one, null otherwise. 102 const Expr *getExpr(const Function *F, CodePtr PC) const; 103 /// Returns the location from which an opcode originates. 104 SourceLocation getLocation(const Function *F, CodePtr PC) const; 105 SourceRange getRange(const Function *F, CodePtr PC) const; 106 }; 107 108 } // namespace interp 109 } // namespace clang 110 111 #endif 112