1 //===- DXContainerEmitter.cpp - Convert YAML to a DXContainer -------------===//
2 //
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
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// Binary emitter for yaml to DXContainer binary
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/BinaryFormat/DXContainer.h"
15 #include "llvm/ObjectYAML/ObjectYAML.h"
16 #include "llvm/ObjectYAML/yaml2obj.h"
17 #include "llvm/Support/Errc.h"
18 #include "llvm/Support/Error.h"
19 #include "llvm/Support/raw_ostream.h"
20 
21 using namespace llvm;
22 
23 namespace {
24 class DXContainerWriter {
25 public:
DXContainerWriter(DXContainerYAML::Object & ObjectFile)26   DXContainerWriter(DXContainerYAML::Object &ObjectFile)
27       : ObjectFile(ObjectFile) {}
28 
29   Error write(raw_ostream &OS);
30 
31 private:
32   DXContainerYAML::Object &ObjectFile;
33 
34   Error computePartOffsets();
35   Error validatePartOffsets();
36   Error validateSize(uint32_t Computed);
37 
38   void writeHeader(raw_ostream &OS);
39   void writeParts(raw_ostream &OS);
40 };
41 } // namespace
42 
validateSize(uint32_t Computed)43 Error DXContainerWriter::validateSize(uint32_t Computed) {
44   if (!ObjectFile.Header.FileSize)
45     ObjectFile.Header.FileSize = Computed;
46   else if (*ObjectFile.Header.FileSize < Computed)
47     return createStringError(errc::result_out_of_range,
48                              "File size specified is too small.");
49   return Error::success();
50 }
51 
validatePartOffsets()52 Error DXContainerWriter::validatePartOffsets() {
53   if (ObjectFile.Parts.size() != ObjectFile.Header.PartOffsets->size())
54     return createStringError(
55         errc::invalid_argument,
56         "Mismatch between number of parts and part offsets.");
57   uint32_t RollingOffset =
58       sizeof(dxbc::Header) + (ObjectFile.Header.PartCount * sizeof(uint32_t));
59   for (auto I : llvm::zip(ObjectFile.Parts, *ObjectFile.Header.PartOffsets)) {
60     if (RollingOffset > std::get<1>(I))
61       return createStringError(errc::invalid_argument,
62                                "Offset mismatch, not enough space for data.");
63     RollingOffset =
64         std::get<1>(I) + sizeof(dxbc::PartHeader) + std::get<0>(I).Size;
65   }
66   if (Error Err = validateSize(RollingOffset))
67     return Err;
68 
69   return Error::success();
70 }
71 
computePartOffsets()72 Error DXContainerWriter::computePartOffsets() {
73   if (ObjectFile.Header.PartOffsets)
74     return validatePartOffsets();
75   uint32_t RollingOffset =
76       sizeof(dxbc::Header) + (ObjectFile.Header.PartCount * sizeof(uint32_t));
77   ObjectFile.Header.PartOffsets = std::vector<uint32_t>();
78   for (const auto &Part : ObjectFile.Parts) {
79     ObjectFile.Header.PartOffsets->push_back(RollingOffset);
80     RollingOffset += sizeof(dxbc::PartHeader) + Part.Size;
81   }
82   if (Error Err = validateSize(RollingOffset))
83     return Err;
84 
85   return Error::success();
86 }
87 
writeHeader(raw_ostream & OS)88 void DXContainerWriter::writeHeader(raw_ostream &OS) {
89   dxbc::Header Header;
90   memcpy(Header.Magic, "DXBC", 4);
91   memcpy(Header.FileHash.Digest, ObjectFile.Header.Hash.data(), 16);
92   Header.Version.Major = ObjectFile.Header.Version.Major;
93   Header.Version.Minor = ObjectFile.Header.Version.Minor;
94   Header.FileSize = *ObjectFile.Header.FileSize;
95   Header.PartCount = ObjectFile.Parts.size();
96   if (sys::IsBigEndianHost)
97     Header.swapBytes();
98   OS.write(reinterpret_cast<char *>(&Header), sizeof(Header));
99   SmallVector<uint32_t> Offsets(ObjectFile.Header.PartOffsets->begin(),
100                                 ObjectFile.Header.PartOffsets->end());
101   if (sys::IsBigEndianHost)
102     for (auto &O : Offsets)
103       sys::swapByteOrder(O);
104   OS.write(reinterpret_cast<char *>(Offsets.data()),
105            Offsets.size() * sizeof(uint32_t));
106 }
107 
writeParts(raw_ostream & OS)108 void DXContainerWriter::writeParts(raw_ostream &OS) {
109   uint32_t RollingOffset =
110       sizeof(dxbc::Header) + (ObjectFile.Header.PartCount * sizeof(uint32_t));
111   for (auto I : llvm::zip(ObjectFile.Parts, *ObjectFile.Header.PartOffsets)) {
112     if (RollingOffset < std::get<1>(I)) {
113       uint32_t PadBytes = std::get<1>(I) - RollingOffset;
114       OS.write_zeros(PadBytes);
115     }
116     DXContainerYAML::Part P = std::get<0>(I);
117     OS.write(P.Name.c_str(), 4);
118     if (sys::IsBigEndianHost)
119       sys::swapByteOrder(P.Size);
120     OS.write(reinterpret_cast<const char *>(&P.Size), sizeof(uint32_t));
121     RollingOffset = std::get<1>(I) + sizeof(dxbc::PartHeader);
122 
123     if (P.Name == "DXIL" && P.Program) {
124       dxbc::ProgramHeader Header;
125       Header.MajorVersion = P.Program->MajorVersion;
126       Header.MinorVersion = P.Program->MinorVersion;
127       Header.Unused = 0;
128       Header.ShaderKind = P.Program->ShaderKind;
129       memcpy(Header.Bitcode.Magic, "DXIL", 4);
130       Header.Bitcode.MajorVersion = P.Program->DXILMajorVersion;
131       Header.Bitcode.MinorVersion = P.Program->DXILMinorVersion;
132       Header.Bitcode.Unused = 0;
133 
134       // Compute the optional fields if needed...
135       if (P.Program->DXILOffset)
136         Header.Bitcode.Offset = P.Program->DXILOffset.value();
137       else
138         Header.Bitcode.Offset = sizeof(dxbc::BitcodeHeader);
139 
140       if (P.Program->DXILSize)
141         Header.Bitcode.Size = P.Program->DXILSize.value();
142       else
143         Header.Bitcode.Size = P.Program->DXIL ? P.Program->DXIL->size() : 0;
144 
145       if (P.Program->Size)
146         Header.Size = P.Program->Size.value();
147       else
148         Header.Size = sizeof(dxbc::ProgramHeader) + Header.Bitcode.Size;
149 
150       uint32_t BitcodeOffset = Header.Bitcode.Offset;
151       if (sys::IsBigEndianHost)
152         Header.swapBytes();
153       OS.write(reinterpret_cast<const char *>(&Header),
154                sizeof(dxbc::ProgramHeader));
155       if (P.Program->DXIL) {
156         if (BitcodeOffset > sizeof(dxbc::BitcodeHeader)) {
157           uint32_t PadBytes = BitcodeOffset - sizeof(dxbc::BitcodeHeader);
158           OS.write_zeros(PadBytes);
159         }
160         OS.write(reinterpret_cast<char *>(P.Program->DXIL->data()),
161                  P.Program->DXIL->size());
162       }
163     }
164   }
165 }
166 
write(raw_ostream & OS)167 Error DXContainerWriter::write(raw_ostream &OS) {
168   if (Error Err = computePartOffsets())
169     return Err;
170   writeHeader(OS);
171   writeParts(OS);
172   return Error::success();
173 }
174 
175 namespace llvm {
176 namespace yaml {
177 
yaml2dxcontainer(DXContainerYAML::Object & Doc,raw_ostream & Out,ErrorHandler EH)178 bool yaml2dxcontainer(DXContainerYAML::Object &Doc, raw_ostream &Out,
179                       ErrorHandler EH) {
180   DXContainerWriter Writer(Doc);
181   if (Error Err = Writer.write(Out)) {
182     handleAllErrors(std::move(Err),
183                     [&](const ErrorInfoBase &Err) { EH(Err.message()); });
184     return false;
185   }
186   return true;
187 }
188 
189 } // namespace yaml
190 } // namespace llvm
191