xref: /freebsd/contrib/llvm-project/llvm/lib/Target/AMDGPU/AMDGPUUnifyMetadata.cpp (revision 770cf0a5f02dc8983a89c6568d741fbc25baa999)
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/IR/Constants.h"
16 #include "llvm/IR/Module.h"
17 #include "llvm/IR/PassManager.h"
18 #include "llvm/Pass.h"
19 
20 using namespace llvm;
21 
22 namespace {
23 
24   namespace kOCLMD {
25 
26     const char SpirVer[]            = "opencl.spir.version";
27     const char OCLVer[]             = "opencl.ocl.version";
28     const char UsedExt[]            = "opencl.used.extensions";
29     const char UsedOptCoreFeat[]    = "opencl.used.optional.core.features";
30     const char CompilerOptions[]    = "opencl.compiler.options";
31     const char LLVMIdent[]          = "llvm.ident";
32 
33   } // end namespace kOCLMD
34 
35     /// Unify version metadata.
36     /// \return true if changes are made.
37     /// Assume the named metadata has operands each of which is a pair of
38     /// integer constant, e.g.
39     /// !Name = {!n1, !n2}
40     /// !n1 = {i32 1, i32 2}
41     /// !n2 = {i32 2, i32 0}
42     /// Keep the largest version as the sole operand if PickFirst is false.
43     /// Otherwise pick it from the first value, representing kernel module.
44     bool unifyVersionMD(Module &M, StringRef Name, bool PickFirst) {
45       auto *NamedMD = M.getNamedMetadata(Name);
46       if (!NamedMD || NamedMD->getNumOperands() <= 1)
47         return false;
48       MDNode *MaxMD = nullptr;
49       auto MaxVer = 0U;
50       for (auto *VersionMD : NamedMD->operands()) {
51         assert(VersionMD->getNumOperands() == 2);
52         auto *CMajor = mdconst::extract<ConstantInt>(VersionMD->getOperand(0));
53         auto VersionMajor = CMajor->getZExtValue();
54         auto *CMinor = mdconst::extract<ConstantInt>(VersionMD->getOperand(1));
55         auto VersionMinor = CMinor->getZExtValue();
56         auto Ver = (VersionMajor * 100) + (VersionMinor * 10);
57         if (Ver > MaxVer) {
58           MaxVer = Ver;
59           MaxMD = VersionMD;
60         }
61         if (PickFirst)
62           break;
63       }
64       NamedMD->eraseFromParent();
65       NamedMD = M.getOrInsertNamedMetadata(Name);
66       NamedMD->addOperand(MaxMD);
67       return true;
68     }
69 
70   /// Unify version metadata.
71   /// \return true if changes are made.
72   /// Assume the named metadata has operands each of which is a list e.g.
73   /// !Name = {!n1, !n2}
74   /// !n1 = !{!"cl_khr_fp16", {!"cl_khr_fp64"}}
75   /// !n2 = !{!"cl_khr_image"}
76   /// Combine it into a single list with unique operands.
77   bool unifyExtensionMD(Module &M, StringRef Name) {
78     auto *NamedMD = M.getNamedMetadata(Name);
79     if (!NamedMD || NamedMD->getNumOperands() == 1)
80       return false;
81 
82     SmallVector<Metadata *, 4> All;
83     for (auto *MD : NamedMD->operands())
84       for (const auto &Op : MD->operands())
85         if (!llvm::is_contained(All, Op.get()))
86           All.push_back(Op.get());
87 
88     NamedMD->eraseFromParent();
89     NamedMD = M.getOrInsertNamedMetadata(Name);
90     for (const auto &MD : All)
91       NamedMD->addOperand(MDNode::get(M.getContext(), MD));
92 
93     return true;
94   }
95 
96   /// Unify multiple OpenCL metadata due to linking.
97   bool unifyMetadataImpl(Module &M) {
98     const char *Vers[] = {kOCLMD::SpirVer, kOCLMD::OCLVer};
99     const char *Exts[] = {kOCLMD::UsedExt, kOCLMD::UsedOptCoreFeat,
100                           kOCLMD::CompilerOptions, kOCLMD::LLVMIdent};
101 
102     bool Changed = false;
103 
104     for (auto &I : Vers)
105       Changed |= unifyVersionMD(M, I, true);
106 
107     for (auto &I : Exts)
108       Changed |= unifyExtensionMD(M, I);
109 
110     return Changed;
111   }
112 
113   } // end anonymous namespace
114 
115   PreservedAnalyses AMDGPUUnifyMetadataPass::run(Module &M,
116                                                  ModuleAnalysisManager &AM) {
117     return unifyMetadataImpl(M) ? PreservedAnalyses::none()
118                                 : PreservedAnalyses::all();
119   }
120