1 //===-- llvm/CodeGen/ByteStreamer.h - ByteStreamer class --------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains a class that can take bytes that would normally be 11 // streamed via the AsmPrinter. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_BYTESTREAMER_H 16 #define LLVM_LIB_CODEGEN_ASMPRINTER_BYTESTREAMER_H 17 18 #include "DIEHash.h" 19 #include "llvm/ADT/ArrayRef.h" 20 #include "llvm/CodeGen/AsmPrinter.h" 21 #include "llvm/MC/MCStreamer.h" 22 #include "llvm/Support/LEB128.h" 23 #include <string> 24 25 namespace llvm { 26 class ByteStreamer { 27 public: ~ByteStreamer()28 virtual ~ByteStreamer() {} 29 30 // For now we're just handling the calls we need for dwarf emission/hashing. 31 virtual void EmitInt8(uint8_t Byte, const Twine &Comment = "") = 0; 32 virtual void EmitSLEB128(uint64_t DWord, const Twine &Comment = "") = 0; 33 virtual void EmitULEB128(uint64_t DWord, const Twine &Comment = "") = 0; 34 }; 35 36 class APByteStreamer : public ByteStreamer { 37 private: 38 AsmPrinter &AP; 39 40 public: APByteStreamer(AsmPrinter & Asm)41 APByteStreamer(AsmPrinter &Asm) : AP(Asm) {} EmitInt8(uint8_t Byte,const Twine & Comment)42 void EmitInt8(uint8_t Byte, const Twine &Comment) override { 43 AP.OutStreamer->AddComment(Comment); 44 AP.EmitInt8(Byte); 45 } EmitSLEB128(uint64_t DWord,const Twine & Comment)46 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override { 47 AP.OutStreamer->AddComment(Comment); 48 AP.EmitSLEB128(DWord); 49 } EmitULEB128(uint64_t DWord,const Twine & Comment)50 void EmitULEB128(uint64_t DWord, const Twine &Comment) override { 51 AP.OutStreamer->AddComment(Comment); 52 AP.EmitULEB128(DWord); 53 } 54 }; 55 56 class HashingByteStreamer : public ByteStreamer { 57 private: 58 DIEHash &Hash; 59 public: HashingByteStreamer(DIEHash & H)60 HashingByteStreamer(DIEHash &H) : Hash(H) {} EmitInt8(uint8_t Byte,const Twine & Comment)61 void EmitInt8(uint8_t Byte, const Twine &Comment) override { 62 Hash.update(Byte); 63 } EmitSLEB128(uint64_t DWord,const Twine & Comment)64 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override { 65 Hash.addSLEB128(DWord); 66 } EmitULEB128(uint64_t DWord,const Twine & Comment)67 void EmitULEB128(uint64_t DWord, const Twine &Comment) override { 68 Hash.addULEB128(DWord); 69 } 70 }; 71 72 class BufferByteStreamer : public ByteStreamer { 73 private: 74 SmallVectorImpl<char> &Buffer; 75 SmallVectorImpl<std::string> &Comments; 76 77 /// \brief Only verbose textual output needs comments. This will be set to 78 /// true for that case, and false otherwise. If false, comments passed in to 79 /// the emit methods will be ignored. 80 bool GenerateComments; 81 82 public: BufferByteStreamer(SmallVectorImpl<char> & Buffer,SmallVectorImpl<std::string> & Comments,bool GenerateComments)83 BufferByteStreamer(SmallVectorImpl<char> &Buffer, 84 SmallVectorImpl<std::string> &Comments, 85 bool GenerateComments) 86 : Buffer(Buffer), Comments(Comments), GenerateComments(GenerateComments) {} EmitInt8(uint8_t Byte,const Twine & Comment)87 void EmitInt8(uint8_t Byte, const Twine &Comment) override { 88 Buffer.push_back(Byte); 89 if (GenerateComments) 90 Comments.push_back(Comment.str()); 91 } EmitSLEB128(uint64_t DWord,const Twine & Comment)92 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override { 93 raw_svector_ostream OSE(Buffer); 94 encodeSLEB128(DWord, OSE); 95 if (GenerateComments) 96 Comments.push_back(Comment.str()); 97 } EmitULEB128(uint64_t DWord,const Twine & Comment)98 void EmitULEB128(uint64_t DWord, const Twine &Comment) override { 99 raw_svector_ostream OSE(Buffer); 100 encodeULEB128(DWord, OSE); 101 if (GenerateComments) 102 Comments.push_back(Comment.str()); 103 } 104 }; 105 106 } 107 108 #endif 109