llvm/lib/Target/NVPTX/NVPTXAtomicLower.cpp

   1 //===-- NVPTXAtomicLower.cpp - Lower atomics of local memory ----*- C++ -*-===//
   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 //  Lower atomics of local memory to simple load/stores
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "NVPTXAtomicLower.h"
  14 #include "llvm/CodeGen/StackProtector.h"
  15 #include "llvm/IR/Constants.h"
  16 #include "llvm/IR/Function.h"
  17 #include "llvm/IR/IRBuilder.h"
  18 #include "llvm/IR/InstIterator.h"
  19 #include "llvm/IR/Instructions.h"
  20 #include "llvm/Transforms/Utils/LowerAtomic.h"
  21
  22 #include "MCTargetDesc/NVPTXBaseInfo.h"
  23 using namespace llvm;
  24
  25 namespace {
  26 // Hoisting the alloca instructions in the non-entry blocks to the entry
  27 // block.
  28 class NVPTXAtomicLower : public FunctionPass {
  29 public:
  30   static char ID; // Pass ID
  31   NVPTXAtomicLower() : FunctionPass(ID) {}
  32
  33   void getAnalysisUsage(AnalysisUsage &AU) const override {
  34     AU.setPreservesCFG();
  35   }
  36
  37   StringRef getPassName() const override {
  38     return "NVPTX lower atomics of local memory";
  39   }
  40
  41   bool runOnFunction(Function &F) override;
  42 };
  43 } // namespace
  44
  45 bool NVPTXAtomicLower::runOnFunction(Function &F) {
  46   SmallVector<AtomicRMWInst *> LocalMemoryAtomics;
  47   for (Instruction &I : instructions(F))
  48     if (AtomicRMWInst *RMWI = dyn_cast<AtomicRMWInst>(&I))
  49       if (RMWI->getPointerAddressSpace() == ADDRESS_SPACE_LOCAL)
  50         LocalMemoryAtomics.push_back(RMWI);
  51
  52   bool Changed = false;
  53   for (AtomicRMWInst *RMWI : LocalMemoryAtomics)
  54     Changed |= lowerAtomicRMWInst(RMWI);
  55   return Changed;
  56 }
  57
  58 char NVPTXAtomicLower::ID = 0;
  59
  60 namespace llvm {
  61 void initializeNVPTXAtomicLowerPass(PassRegistry &);
  62 }
  63
  64 INITIALIZE_PASS(NVPTXAtomicLower, "nvptx-atomic-lower",
  65                 "Lower atomics of local memory to simple load/stores", false,
  66                 false)
  67
  68 FunctionPass *llvm::createNVPTXAtomicLowerPass() {
  69   return new NVPTXAtomicLower();
  70 }