SourceLocation.h revision 25bb23aa20b69b107bbb4526b2d156599c2434ca
1//===--- SourceLocation.h - Compact identifier for Source Files -*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by Chris Lattner and is distributed under 6// the University of Illinois Open Source License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines the SourceLocation class. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_CLANG_SOURCELOCATION_H 15#define LLVM_CLANG_SOURCELOCATION_H 16 17#include <cassert> 18#include "llvm/Bitcode/SerializationFwd.h" 19 20namespace clang { 21 22class SourceManager; 23 24/// SourceLocation - This is a carefully crafted 32-bit identifier that encodes 25/// a full include stack, line and column number information for a position in 26/// an input translation unit. 27class SourceLocation { 28 unsigned ID; 29public: 30 enum { 31 // FileID Layout: 32 // bit 31: 0 -> FileID, 1 -> MacroID (invalid for FileID) 33 // 30...17 -> FileID of source location, index into SourceManager table. 34 FileIDBits = 14, 35 // 0...16 -> Index into the chunk of the specified FileID. 36 FilePosBits = 32-1-FileIDBits, 37 38 // MacroID Layout: 39 // bit 31: 1 -> MacroID, 0 -> FileID (invalid for MacroID) 40 41 // bit 30: 1 -> Start of macro expansion marker. 42 MacroStartOfExpansionBit = 30, 43 // bit 29: 1 -> End of macro expansion marker. 44 MacroEndOfExpansionBit = 29, 45 // bits 28...9 -> MacroID number. 46 MacroIDBits = 20, 47 // bits 8...0 -> Macro Physical offset 48 MacroPhysOffsBits = 9, 49 50 51 // Useful constants. 52 ChunkSize = (1 << FilePosBits) 53 }; 54 55 SourceLocation() : ID(0) {} // 0 is an invalid FileID. 56 57 bool isFileID() const { return (ID >> 31) == 0; } 58 bool isMacroID() const { return (ID >> 31) != 0; } 59 60 /// isValid - Return true if this is a valid SourceLocation object. Invalid 61 /// SourceLocations are often used when events have no corresponding location 62 /// in the source (e.g. a diagnostic is required for a command line option). 63 /// 64 bool isValid() const { return ID != 0; } 65 bool isInvalid() const { return ID == 0; } 66 67 static SourceLocation getFileLoc(unsigned FileID, unsigned FilePos) { 68 SourceLocation L; 69 // If a FilePos is larger than (1<<FilePosBits), the SourceManager makes 70 // enough consequtive FileIDs that we have one for each chunk. 71 if (FilePos >= ChunkSize) { 72 FileID += FilePos >> FilePosBits; 73 FilePos &= ChunkSize-1; 74 } 75 76 // FIXME: Find a way to handle out of FileID bits! Maybe MaxFileID is an 77 // escape of some sort? 78 assert(FileID < (1 << FileIDBits) && "Out of fileid's"); 79 80 L.ID = (FileID << FilePosBits) | FilePos; 81 return L; 82 } 83 84 static bool isValidMacroPhysOffs(int Val) { 85 if (Val >= 0) 86 return Val < (1 << (MacroPhysOffsBits-1)); 87 return -Val < (1 << (MacroPhysOffsBits-1)); 88 } 89 90 static SourceLocation getMacroLoc(unsigned MacroID, int PhysOffs, 91 bool isExpansionStart, bool isExpansionEnd){ 92 assert(MacroID < (1 << MacroIDBits) && "Too many macros!"); 93 assert(isValidMacroPhysOffs(PhysOffs) && "Physoffs too large!"); 94 95 // Mask off sign bits. 96 PhysOffs &= (1 << MacroPhysOffsBits)-1; 97 98 SourceLocation L; 99 L.ID = (1 << 31) | 100 (isExpansionStart << MacroStartOfExpansionBit) | 101 (isExpansionEnd << MacroEndOfExpansionBit) | 102 (MacroID << MacroPhysOffsBits) | 103 PhysOffs; 104 return L; 105 } 106 107 108 /// getFileID - Return the file identifier for this SourceLocation. This 109 /// FileID can be used with the SourceManager object to obtain an entire 110 /// include stack for a file position reference. 111 unsigned getFileID() const { 112 assert(isFileID() && "can't get the file id of a non-file sloc!"); 113 return ID >> FilePosBits; 114 } 115 116 /// getRawFilePos - Return the byte offset from the start of the file-chunk 117 /// referred to by FileID. This method should not be used to get the offset 118 /// from the start of the file, instead you should use 119 /// SourceManager::getFilePos. This method will be incorrect for large files. 120 unsigned getRawFilePos() const { 121 assert(isFileID() && "can't get the file id of a non-file sloc!"); 122 return ID & (ChunkSize-1); 123 } 124 125 unsigned getMacroID() const { 126 assert(isMacroID() && "Is not a macro id!"); 127 return (ID >> MacroPhysOffsBits) & ((1 << MacroIDBits)-1); 128 } 129 130 int getMacroPhysOffs() const { 131 assert(isMacroID() && "Is not a macro id!"); 132 int Val = ID & ((1 << MacroPhysOffsBits)-1); 133 // Sign extend it properly. 134 unsigned ShAmt = sizeof(int)*8 - MacroPhysOffsBits; 135 return (Val << ShAmt) >> ShAmt; 136 } 137 138 /// getFileLocWithOffset - Return a source location with the specified offset 139 /// from this file SourceLocation. 140 SourceLocation getFileLocWithOffset(int Offset) const { 141 unsigned FileID = getFileID(); 142 Offset += getRawFilePos(); 143 // Handle negative offsets correctly. 144 while (Offset < 0) { 145 --FileID; 146 Offset += ChunkSize; 147 } 148 return getFileLoc(FileID, Offset); 149 } 150 151 /// getRawEncoding - When a SourceLocation itself cannot be used, this returns 152 /// an (opaque) 32-bit integer encoding for it. This should only be passed 153 /// to SourceLocation::getFromRawEncoding, it should not be inspected 154 /// directly. 155 unsigned getRawEncoding() const { return ID; } 156 157 /// getFromRawEncoding - Turn a raw encoding of a SourceLocation object into 158 /// a real SourceLocation. 159 static SourceLocation getFromRawEncoding(unsigned Encoding) { 160 SourceLocation X; 161 X.ID = Encoding; 162 return X; 163 } 164 165 /// Emit - Emit this SourceLocation object to Bitcode. 166 void Emit(llvm::Serializer& S) const; 167 168 /// ReadVal - Read a SourceLocation object from Bitcode. 169 static SourceLocation ReadVal(llvm::Deserializer& D); 170}; 171 172inline bool operator==(const SourceLocation &LHS, const SourceLocation &RHS) { 173 return LHS.getRawEncoding() == RHS.getRawEncoding(); 174} 175 176inline bool operator!=(const SourceLocation &LHS, const SourceLocation &RHS) { 177 return !(LHS == RHS); 178} 179 180/// SourceRange - a trival tuple used to represent a source range. 181class SourceRange { 182 SourceLocation B; 183 SourceLocation E; 184public: 185 SourceRange(): B(SourceLocation()), E(SourceLocation()) {} 186 SourceRange(SourceLocation loc) : B(loc), E(loc) {} 187 SourceRange(SourceLocation begin, SourceLocation end) : B(begin), E(end) {} 188 189 SourceLocation getBegin() const { return B; } 190 SourceLocation getEnd() const { return E; } 191 192 void setBegin(SourceLocation b) { B = b; } 193 void setEnd(SourceLocation e) { E = e; } 194 195 bool isValid() const { return B.isValid() && E.isValid(); } 196 197 /// Emit - Emit this SourceRange object to Bitcode. 198 void Emit(llvm::Serializer& S) const; 199 200 /// ReadVal - Read a SourceRange object from Bitcode. 201 static SourceRange ReadVal(llvm::Deserializer& D); 202}; 203 204/// FullContextSourceLocation - A tuple containing both a SourceLocation 205/// and its associated SourceManager. Useful for argument passing to functions 206/// that expect both objects. 207class FullContextSourceLocation { 208 SourceLocation Loc; 209 SourceManager* SrcMgr; 210public: 211 explicit FullContextSourceLocation(SourceLocation loc) 212 : Loc(loc), SrcMgr(NULL) {} 213 214 explicit FullContextSourceLocation(SourceLocation loc, SourceManager& smgr) 215 : Loc(loc), SrcMgr(&smgr) {} 216 217 bool isValid() const { return Loc.isValid(); } 218 219 SourceLocation getSourceLocation() const { return Loc; } 220 operator SourceLocation() const { return Loc; } 221 222 SourceManager& getSourceManager() { 223 assert (SrcMgr && "SourceManager is NULL."); 224 return *SrcMgr; 225 } 226 227 const SourceManager& getSourceManager() const { 228 assert (SrcMgr && "SourceManager is NULL."); 229 return *SrcMgr; 230 } 231}; 232 233} // end namespace clang 234 235#endif 236