1 //===- Writer.h -------------------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Linker 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef LLD_COFF_WRITER_H 11 #define LLD_COFF_WRITER_H 12 13 #include "Chunks.h" 14 #include "llvm/ADT/StringRef.h" 15 #include "llvm/Object/COFF.h" 16 #include <chrono> 17 #include <cstdint> 18 #include <vector> 19 20 namespace lld { 21 namespace coff { 22 static const int PageSize = 4096; 23 24 void writeResult(); 25 26 // OutputSection represents a section in an output file. It's a 27 // container of chunks. OutputSection and Chunk are 1:N relationship. 28 // Chunks cannot belong to more than one OutputSections. The writer 29 // creates multiple OutputSections and assign them unique, 30 // non-overlapping file offsets and RVAs. 31 class OutputSection { 32 public: 33 OutputSection(llvm::StringRef N, uint32_t Chars) : Name(N) { 34 Header.Characteristics = Chars; 35 } 36 void addChunk(Chunk *C); 37 void merge(OutputSection *Other); 38 ArrayRef<Chunk *> getChunks() { return Chunks; } 39 void addPermissions(uint32_t C); 40 void setPermissions(uint32_t C); 41 uint64_t getRVA() { return Header.VirtualAddress; } 42 uint64_t getFileOff() { return Header.PointerToRawData; } 43 void writeHeaderTo(uint8_t *Buf); 44 45 // Returns the size of this section in an executable memory image. 46 // This may be smaller than the raw size (the raw size is multiple 47 // of disk sector size, so there may be padding at end), or may be 48 // larger (if that's the case, the loader reserves spaces after end 49 // of raw data). 50 uint64_t getVirtualSize() { return Header.VirtualSize; } 51 52 // Returns the size of the section in the output file. 53 uint64_t getRawSize() { return Header.SizeOfRawData; } 54 55 // Set offset into the string table storing this section name. 56 // Used only when the name is longer than 8 bytes. 57 void setStringTableOff(uint32_t V) { StringTableOff = V; } 58 59 // N.B. The section index is one based. 60 uint32_t SectionIndex = 0; kind()61 62 llvm::StringRef Name; 63 llvm::object::coff_section Header = {}; isExternal()64 65 private: 66 uint32_t StringTableOff = 0; 67 std::vector<Chunk *> Chunks; 68 }; 69 70 } 71 } 72 73 #endif 74