lib/Target/AMDGPU/AMDGPUUnifyMetadata.cpp

   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
  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.
  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 (const 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.
  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 (const 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
 121 ModulePass* llvm::createAMDGPUUnifyMetadataPass() {
 122   return new AMDGPUUnifyMetadata();
 123 }
 124
 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 }