1 //===- DXContainerGlobals.cpp - DXContainer global generator pass ---------===//
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 // DXContainerGlobalsPass implementation.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "DXILShaderFlags.h"
14 #include "DirectX.h"
15 #include "llvm/ADT/StringExtras.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/BinaryFormat/DXContainer.h"
18 #include "llvm/CodeGen/Passes.h"
19 #include "llvm/IR/Constants.h"
20 #include "llvm/InitializePasses.h"
21 #include "llvm/Pass.h"
22 #include "llvm/Support/MD5.h"
23 #include "llvm/Transforms/Utils/ModuleUtils.h"
24
25 using namespace llvm;
26 using namespace llvm::dxil;
27
28 namespace {
29 class DXContainerGlobals : public llvm::ModulePass {
30
31 GlobalVariable *getShaderFlags(Module &M);
32 GlobalVariable *computeShaderHash(Module &M);
33
34 public:
35 static char ID; // Pass identification, replacement for typeid
DXContainerGlobals()36 DXContainerGlobals() : ModulePass(ID) {
37 initializeDXContainerGlobalsPass(*PassRegistry::getPassRegistry());
38 }
39
getPassName() const40 StringRef getPassName() const override {
41 return "DXContainer Global Emitter";
42 }
43
44 bool runOnModule(Module &M) override;
45
getAnalysisUsage(AnalysisUsage & AU) const46 void getAnalysisUsage(AnalysisUsage &AU) const override {
47 AU.setPreservesAll();
48 AU.addRequired<ShaderFlagsAnalysisWrapper>();
49 }
50 };
51
52 } // namespace
53
runOnModule(Module & M)54 bool DXContainerGlobals::runOnModule(Module &M) {
55 llvm::SmallVector<GlobalValue *> Globals;
56 Globals.push_back(getShaderFlags(M));
57 Globals.push_back(computeShaderHash(M));
58
59 appendToCompilerUsed(M, Globals);
60 return true;
61 }
62
getShaderFlags(Module & M)63 GlobalVariable *DXContainerGlobals::getShaderFlags(Module &M) {
64 const uint64_t Flags =
65 (uint64_t)(getAnalysis<ShaderFlagsAnalysisWrapper>().getShaderFlags());
66
67 Constant *FlagsConstant = ConstantInt::get(M.getContext(), APInt(64, Flags));
68 auto *GV = new llvm::GlobalVariable(M, FlagsConstant->getType(), true,
69 GlobalValue::PrivateLinkage,
70 FlagsConstant, "dx.sfi0");
71 GV->setSection("SFI0");
72 GV->setAlignment(Align(4));
73 return GV;
74 }
75
computeShaderHash(Module & M)76 GlobalVariable *DXContainerGlobals::computeShaderHash(Module &M) {
77 auto *DXILConstant =
78 cast<ConstantDataArray>(M.getNamedGlobal("dx.dxil")->getInitializer());
79 MD5 Digest;
80 Digest.update(DXILConstant->getRawDataValues());
81 MD5::MD5Result Result = Digest.final();
82
83 dxbc::ShaderHash HashData = {0, {0}};
84 // The Hash's IncludesSource flag gets set whenever the hashed shader includes
85 // debug information.
86 if (M.debug_compile_units_begin() != M.debug_compile_units_end())
87 HashData.Flags = static_cast<uint32_t>(dxbc::HashFlags::IncludesSource);
88
89 memcpy(reinterpret_cast<void *>(&HashData.Digest), Result.data(), 16);
90 if (sys::IsBigEndianHost)
91 HashData.swapBytes();
92 StringRef Data(reinterpret_cast<char *>(&HashData), sizeof(dxbc::ShaderHash));
93
94 Constant *ModuleConstant =
95 ConstantDataArray::get(M.getContext(), arrayRefFromStringRef(Data));
96 auto *GV = new llvm::GlobalVariable(M, ModuleConstant->getType(), true,
97 GlobalValue::PrivateLinkage,
98 ModuleConstant, "dx.hash");
99 GV->setSection("HASH");
100 GV->setAlignment(Align(4));
101 return GV;
102 }
103
104 char DXContainerGlobals::ID = 0;
105 INITIALIZE_PASS_BEGIN(DXContainerGlobals, "dxil-globals",
106 "DXContainer Global Emitter", false, true)
INITIALIZE_PASS_DEPENDENCY(ShaderFlagsAnalysisWrapper)107 INITIALIZE_PASS_DEPENDENCY(ShaderFlagsAnalysisWrapper)
108 INITIALIZE_PASS_END(DXContainerGlobals, "dxil-globals",
109 "DXContainer Global Emitter", false, true)
110
111 ModulePass *llvm::createDXContainerGlobalsPass() {
112 return new DXContainerGlobals();
113 }
114