1 //===-- llvm/CodeGen/ByteStreamer.h - ByteStreamer class --------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 // This file contains a class that can take bytes that would normally be
10 // streamed via the AsmPrinter.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_BYTESTREAMER_H
15 #define LLVM_LIB_CODEGEN_ASMPRINTER_BYTESTREAMER_H
18 #include "llvm/CodeGen/AsmPrinter.h"
19 #include "llvm/MC/MCStreamer.h"
20 #include "llvm/Support/LEB128.h"
26 ~ByteStreamer() = default;
27 ByteStreamer(const ByteStreamer&) = default;
28 ByteStreamer() = default;
31 // For now we're just handling the calls we need for dwarf emission/hashing.
32 virtual void EmitInt8(uint8_t Byte, const Twine &Comment = "") = 0;
33 virtual void EmitSLEB128(uint64_t DWord, const Twine &Comment = "") = 0;
34 virtual void EmitULEB128(uint64_t DWord, const Twine &Comment = "", unsigned PadTo = 0) = 0;
37 class APByteStreamer final : public ByteStreamer {
42 APByteStreamer(AsmPrinter &Asm) : AP(Asm) {}
43 void EmitInt8(uint8_t Byte, const Twine &Comment) override {
44 AP.OutStreamer->AddComment(Comment);
47 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override {
48 AP.OutStreamer->AddComment(Comment);
49 AP.EmitSLEB128(DWord);
51 void EmitULEB128(uint64_t DWord, const Twine &Comment, unsigned PadTo) override {
52 AP.OutStreamer->AddComment(Comment);
53 AP.EmitULEB128(DWord);
57 class HashingByteStreamer final : public ByteStreamer {
61 HashingByteStreamer(DIEHash &H) : Hash(H) {}
62 void EmitInt8(uint8_t Byte, const Twine &Comment) override {
65 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override {
66 Hash.addSLEB128(DWord);
68 void EmitULEB128(uint64_t DWord, const Twine &Comment, unsigned PadTo) override {
69 Hash.addULEB128(DWord);
73 class BufferByteStreamer final : public ByteStreamer {
75 SmallVectorImpl<char> &Buffer;
76 SmallVectorImpl<std::string> &Comments;
78 /// Only verbose textual output needs comments. This will be set to
79 /// true for that case, and false otherwise. If false, comments passed in to
80 /// the emit methods will be ignored.
81 bool GenerateComments;
84 BufferByteStreamer(SmallVectorImpl<char> &Buffer,
85 SmallVectorImpl<std::string> &Comments,
86 bool GenerateComments)
87 : Buffer(Buffer), Comments(Comments), GenerateComments(GenerateComments) {}
88 void EmitInt8(uint8_t Byte, const Twine &Comment) override {
89 Buffer.push_back(Byte);
91 Comments.push_back(Comment.str());
93 void EmitSLEB128(uint64_t DWord, const Twine &Comment) override {
94 raw_svector_ostream OSE(Buffer);
95 unsigned Length = encodeSLEB128(DWord, OSE);
96 if (GenerateComments) {
97 Comments.push_back(Comment.str());
98 // Add some empty comments to keep the Buffer and Comments vectors aligned
100 for (size_t i = 1; i < Length; ++i)
101 Comments.push_back("");
105 void EmitULEB128(uint64_t DWord, const Twine &Comment, unsigned PadTo) override {
106 raw_svector_ostream OSE(Buffer);
107 unsigned Length = encodeULEB128(DWord, OSE, PadTo);
108 if (GenerateComments) {
109 Comments.push_back(Comment.str());
110 // Add some empty comments to keep the Buffer and Comments vectors aligned
112 for (size_t i = 1; i < Length; ++i)
113 Comments.push_back("");