1 //===- AMDGPUUnifyMetadata.cpp - Unify OpenCL metadata --------------------===//
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 // This pass that unifies multiple OpenCL metadata due to linking.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "AMDGPU.h"
15 #include "llvm/ADT/SmallVector.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/IR/Constants.h"
18 #include "llvm/IR/Metadata.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/Pass.h"
21 #include <algorithm>
22 #include <cassert>
23
24 using namespace llvm;
25
26 namespace {
27
28 namespace kOCLMD {
29
30 const char SpirVer[] = "opencl.spir.version";
31 const char OCLVer[] = "opencl.ocl.version";
32 const char UsedExt[] = "opencl.used.extensions";
33 const char UsedOptCoreFeat[] = "opencl.used.optional.core.features";
34 const char CompilerOptions[] = "opencl.compiler.options";
35 const char LLVMIdent[] = "llvm.ident";
36
37 } // end namespace kOCLMD
38
39 /// Unify multiple OpenCL metadata due to linking.
40 class AMDGPUUnifyMetadata : public ModulePass {
41 public:
42 static char ID;
43
AMDGPUUnifyMetadata()44 explicit AMDGPUUnifyMetadata() : ModulePass(ID) {}
45
46 private:
47 bool runOnModule(Module &M) override;
48
49 /// Unify version metadata.
50 /// \return true if changes are made.
51 /// Assume the named metadata has operands each of which is a pair of
52 /// integer constant, e.g.
53 /// !Name = {!n1, !n2}
54 /// !n1 = {i32 1, i32 2}
55 /// !n2 = {i32 2, i32 0}
56 /// Keep the largest version as the sole operand if PickFirst is false.
57 /// Otherwise pick it from the first value, representing kernel module.
unifyVersionMD(Module & M,StringRef Name,bool PickFirst)58 bool unifyVersionMD(Module &M, StringRef Name, bool PickFirst) {
59 auto NamedMD = M.getNamedMetadata(Name);
60 if (!NamedMD || NamedMD->getNumOperands() <= 1)
61 return false;
62 MDNode *MaxMD = nullptr;
63 auto MaxVer = 0U;
64 for (auto VersionMD : NamedMD->operands()) {
65 assert(VersionMD->getNumOperands() == 2);
66 auto CMajor = mdconst::extract<ConstantInt>(VersionMD->getOperand(0));
67 auto VersionMajor = CMajor->getZExtValue();
68 auto CMinor = mdconst::extract<ConstantInt>(VersionMD->getOperand(1));
69 auto VersionMinor = CMinor->getZExtValue();
70 auto Ver = (VersionMajor * 100) + (VersionMinor * 10);
71 if (Ver > MaxVer) {
72 MaxVer = Ver;
73 MaxMD = VersionMD;
74 }
75 if (PickFirst)
76 break;
77 }
78 NamedMD->eraseFromParent();
79 NamedMD = M.getOrInsertNamedMetadata(Name);
80 NamedMD->addOperand(MaxMD);
81 return true;
82 }
83
84 /// Unify version metadata.
85 /// \return true if changes are made.
86 /// Assume the named metadata has operands each of which is a list e.g.
87 /// !Name = {!n1, !n2}
88 /// !n1 = !{!"cl_khr_fp16", {!"cl_khr_fp64"}}
89 /// !n2 = !{!"cl_khr_image"}
90 /// Combine it into a single list with unique operands.
unifyExtensionMD(Module & M,StringRef Name)91 bool unifyExtensionMD(Module &M, StringRef Name) {
92 auto NamedMD = M.getNamedMetadata(Name);
93 if (!NamedMD || NamedMD->getNumOperands() == 1)
94 return false;
95
96 SmallVector<Metadata *, 4> All;
97 for (auto MD : NamedMD->operands())
98 for (const auto &Op : MD->operands())
99 if (std::find(All.begin(), All.end(), Op.get()) == All.end())
100 All.push_back(Op.get());
101
102 NamedMD->eraseFromParent();
103 NamedMD = M.getOrInsertNamedMetadata(Name);
104 for (const auto &MD : All)
105 NamedMD->addOperand(MDNode::get(M.getContext(), MD));
106
107 return true;
108 }
109 };
110
111 } // end anonymous namespace
112
113 char AMDGPUUnifyMetadata::ID = 0;
114
115 char &llvm::AMDGPUUnifyMetadataID = AMDGPUUnifyMetadata::ID;
116
117 INITIALIZE_PASS(AMDGPUUnifyMetadata, "amdgpu-unify-metadata",
118 "Unify multiple OpenCL metadata due to linking",
119 false, false)
120
createAMDGPUUnifyMetadataPass()121 ModulePass* llvm::createAMDGPUUnifyMetadataPass() {
122 return new AMDGPUUnifyMetadata();
123 }
124
runOnModule(Module & M)125 bool AMDGPUUnifyMetadata::runOnModule(Module &M) {
126 const char* Vers[] = {
127 kOCLMD::SpirVer,
128 kOCLMD::OCLVer
129 };
130 const char* Exts[] = {
131 kOCLMD::UsedExt,
132 kOCLMD::UsedOptCoreFeat,
133 kOCLMD::CompilerOptions,
134 kOCLMD::LLVMIdent
135 };
136
137 bool Changed = false;
138
139 for (auto &I : Vers)
140 Changed |= unifyVersionMD(M, I, true);
141
142 for (auto &I : Exts)
143 Changed |= unifyExtensionMD(M, I);
144
145 return Changed;
146 }
147