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() = default; 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 explicit operator bool() const { return Ptr; } 52 bool operator<=(const CodePtr &RHS) const { return Ptr <= RHS.Ptr; } 53 bool operator>=(const CodePtr &RHS) const { return Ptr >= RHS.Ptr; } 54 55 /// Reads data and advances the pointer. 56 template <typename T> std::enable_if_t<!std::is_pointer<T>::value, T> read() { 57 assert(aligned(Ptr)); 58 using namespace llvm::support; 59 T Value = endian::read<T, llvm::endianness::native>(Ptr); 60 Ptr += align(sizeof(T)); 61 return Value; 62 } 63 64 private: 65 friend class Function; 66 /// Constructor used by Function to generate pointers. 67 CodePtr(const std::byte *Ptr) : Ptr(Ptr) {} 68 /// Pointer into the code owned by a function. 69 const std::byte *Ptr = nullptr; 70 }; 71 72 /// Describes the statement/declaration an opcode was generated from. 73 class SourceInfo final { 74 public: 75 SourceInfo() {} 76 SourceInfo(const Stmt *E) : Source(E) {} 77 SourceInfo(const Decl *D) : Source(D) {} 78 79 SourceLocation getLoc() const; 80 SourceRange getRange() const; 81 82 const Stmt *asStmt() const { 83 return dyn_cast_if_present<const Stmt *>(Source); 84 } 85 const Decl *asDecl() const { 86 return dyn_cast_if_present<const Decl *>(Source); 87 } 88 const Expr *asExpr() const; 89 90 operator bool() const { return !Source.isNull(); } 91 92 private: 93 llvm::PointerUnion<const Decl *, const Stmt *> Source; 94 }; 95 96 using SourceMap = std::vector<std::pair<unsigned, SourceInfo>>; 97 98 /// Interface for classes which map locations to sources. 99 class SourceMapper { 100 public: 101 virtual ~SourceMapper() {} 102 103 /// Returns source information for a given PC in a function. 104 virtual SourceInfo getSource(const Function *F, CodePtr PC) const = 0; 105 106 /// Returns the expression if an opcode belongs to one, null otherwise. 107 const Expr *getExpr(const Function *F, CodePtr PC) const; 108 /// Returns the location from which an opcode originates. 109 SourceLocation getLocation(const Function *F, CodePtr PC) const; 110 SourceRange getRange(const Function *F, CodePtr PC) const; 111 }; 112 113 } // namespace interp 114 } // namespace clang 115 116 #endif 117