xref: /freebsd/contrib/llvm-project/llvm/lib/Target/DirectX/DXContainerGlobals.cpp (revision 7ef62cebc2f965b0f640263e179276928885e33d)
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/StringRef.h"
16 #include "llvm/BinaryFormat/DXContainer.h"
17 #include "llvm/CodeGen/Passes.h"
18 #include "llvm/IR/Constants.h"
19 #include "llvm/InitializePasses.h"
20 #include "llvm/Pass.h"
21 #include "llvm/Support/MD5.h"
22 #include "llvm/Transforms/Utils/ModuleUtils.h"
23 
24 using namespace llvm;
25 using namespace llvm::dxil;
26 
27 namespace {
28 class DXContainerGlobals : public llvm::ModulePass {
29 
30   GlobalVariable *getShaderFlags(Module &M);
31   GlobalVariable *computeShaderHash(Module &M);
32 
33 public:
34   static char ID; // Pass identification, replacement for typeid
35   DXContainerGlobals() : ModulePass(ID) {
36     initializeDXContainerGlobalsPass(*PassRegistry::getPassRegistry());
37   }
38 
39   StringRef getPassName() const override {
40     return "DXContainer Global Emitter";
41   }
42 
43   bool runOnModule(Module &M) override;
44 
45   void getAnalysisUsage(AnalysisUsage &AU) const override {
46     AU.setPreservesAll();
47     AU.addRequired<ShaderFlagsAnalysisWrapper>();
48   }
49 };
50 
51 } // namespace
52 
53 bool DXContainerGlobals::runOnModule(Module &M) {
54   llvm::SmallVector<GlobalValue *> Globals;
55   Globals.push_back(getShaderFlags(M));
56   Globals.push_back(computeShaderHash(M));
57 
58   appendToCompilerUsed(M, Globals);
59   return true;
60 }
61 
62 GlobalVariable *DXContainerGlobals::getShaderFlags(Module &M) {
63   const uint64_t Flags =
64       (uint64_t)(getAnalysis<ShaderFlagsAnalysisWrapper>().getShaderFlags());
65 
66   Constant *FlagsConstant = ConstantInt::get(M.getContext(), APInt(64, Flags));
67   auto *GV = new llvm::GlobalVariable(M, FlagsConstant->getType(), true,
68                                       GlobalValue::PrivateLinkage,
69                                       FlagsConstant, "dx.sfi0");
70   GV->setSection("SFI0");
71   GV->setAlignment(Align(4));
72   return GV;
73 }
74 
75 GlobalVariable *DXContainerGlobals::computeShaderHash(Module &M) {
76   auto *DXILConstant =
77       cast<ConstantDataArray>(M.getNamedGlobal("dx.dxil")->getInitializer());
78   MD5 Digest;
79   Digest.update(DXILConstant->getRawDataValues());
80   MD5::MD5Result Result = Digest.final();
81 
82   dxbc::ShaderHash HashData = {0, {0}};
83   // The Hash's IncludesSource flag gets set whenever the hashed shader includes
84   // debug information.
85   if (M.debug_compile_units_begin() != M.debug_compile_units_end())
86     HashData.Flags = static_cast<uint32_t>(dxbc::HashFlags::IncludesSource);
87 
88   memcpy(reinterpret_cast<void *>(&HashData.Digest), Result.data(), 16);
89   if (sys::IsBigEndianHost)
90     HashData.swapBytes();
91   StringRef Data(reinterpret_cast<char *>(&HashData), sizeof(dxbc::ShaderHash));
92 
93   Constant *ModuleConstant =
94       ConstantDataArray::get(M.getContext(), arrayRefFromStringRef(Data));
95   auto *GV = new llvm::GlobalVariable(M, ModuleConstant->getType(), true,
96                                       GlobalValue::PrivateLinkage,
97                                       ModuleConstant, "dx.hash");
98   GV->setSection("HASH");
99   GV->setAlignment(Align(4));
100   return GV;
101 }
102 
103 char DXContainerGlobals::ID = 0;
104 INITIALIZE_PASS_BEGIN(DXContainerGlobals, "dxil-globals",
105                       "DXContainer Global Emitter", false, true)
106 INITIALIZE_PASS_DEPENDENCY(ShaderFlagsAnalysisWrapper)
107 INITIALIZE_PASS_END(DXContainerGlobals, "dxil-globals",
108                     "DXContainer Global Emitter", false, true)
109 
110 ModulePass *llvm::createDXContainerGlobalsPass() {
111   return new DXContainerGlobals();
112 }
113