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/CodeGen/AsmPrinter.h" 20 #include "llvm/MC/MCStreamer.h" 21 #include "llvm/Support/LEB128.h" 22 #include <string> 23 24 namespace llvm { 25 class ByteStreamer { 26 protected: 27 ~ByteStreamer() = default; 28 ByteStreamer(const ByteStreamer&) = default; 29 ByteStreamer() = default; 30 31 public: 32 // For now we're just handling the calls we need for dwarf emission/hashing. 33 virtual void EmitInt8(uint8_t Byte, const Twine &Comment = "") = 0; 34 virtual void EmitSLEB128(uint64_t DWord, const Twine &Comment = "") = 0; 35 virtual void EmitULEB128(uint64_t DWord, const Twine &Comment = "") = 0; 36 }; 37 38 class APByteStreamer final : public ByteStreamer { 39 private: 40 AsmPrinter &AP; 41 42 public: 43 APByteStreamer(AsmPrinter &Asm) : AP(Asm) {} 44 void EmitInt8(uint8_t Byte, const Twine &Comment) override { 45 AP.OutStreamer->AddComment(Comment); 46 AP.EmitInt8(Byte); 47 } 48 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override { 49 AP.OutStreamer->AddComment(Comment); 50 AP.EmitSLEB128(DWord); 51 } 52 void EmitULEB128(uint64_t DWord, const Twine &Comment) override { 53 AP.OutStreamer->AddComment(Comment); 54 AP.EmitULEB128(DWord); 55 } 56 }; 57 58 class HashingByteStreamer final : public ByteStreamer { 59 private: 60 DIEHash &Hash; 61 public: 62 HashingByteStreamer(DIEHash &H) : Hash(H) {} 63 void EmitInt8(uint8_t Byte, const Twine &Comment) override { 64 Hash.update(Byte); 65 } 66 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override { 67 Hash.addSLEB128(DWord); 68 } 69 void EmitULEB128(uint64_t DWord, const Twine &Comment) override { 70 Hash.addULEB128(DWord); 71 } 72 }; 73 74 class BufferByteStreamer final : public ByteStreamer { 75 private: 76 SmallVectorImpl<char> &Buffer; 77 SmallVectorImpl<std::string> &Comments; 78 79 /// \brief Only verbose textual output needs comments. This will be set to 80 /// true for that case, and false otherwise. If false, comments passed in to 81 /// the emit methods will be ignored. 82 bool GenerateComments; 83 84 public: 85 BufferByteStreamer(SmallVectorImpl<char> &Buffer, 86 SmallVectorImpl<std::string> &Comments, 87 bool GenerateComments) 88 : Buffer(Buffer), Comments(Comments), GenerateComments(GenerateComments) {} 89 void EmitInt8(uint8_t Byte, const Twine &Comment) override { 90 Buffer.push_back(Byte); 91 if (GenerateComments) 92 Comments.push_back(Comment.str()); 93 } 94 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override { 95 raw_svector_ostream OSE(Buffer); 96 encodeSLEB128(DWord, OSE); 97 if (GenerateComments) 98 Comments.push_back(Comment.str()); 99 } 100 void EmitULEB128(uint64_t DWord, const Twine &Comment) override { 101 raw_svector_ostream OSE(Buffer); 102 encodeULEB128(DWord, OSE); 103 if (GenerateComments) 104 Comments.push_back(Comment.str()); 105 } 106 }; 107 108 } 109 110 #endif 111
