lib/SamplerUtils.cpp

// Copyright 2023 The Clspv Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "SamplerUtils.h"
#include "Builtins.h"
#include "BuiltinsEnum.h"
#include "Constants.h"
#include "Types.h"

using namespace llvm;

namespace clspv {

Value *GetImageDimFP(Module &M, IRBuilder<> &B, Value *Img, Type *ImgTy) {
  auto float4Ty = FixedVectorType::get(B.getFloatTy(), 4);
  auto getImageSizesFct = M.getOrInsertFunction(
      "_Z13get_image_dim11ocl_image3d",
      FunctionType::get(FixedVectorType::get(B.getInt32Ty(), 4), {ImgTy},
                        false));
  Value *ImgSizes = B.CreateCall(getImageSizesFct, {Img});
  return B.CreateSIToFP(ImgSizes, float4Ty);
}

Value *NormalizedCoordinate(Module &M, IRBuilder<> &B, Value *Coord,
                            Value *ImgDimFP, bool FilteringNearest) {
  if (FilteringNearest) {
    auto float4Ty = FixedVectorType::get(B.getFloatTy(), 4);
    auto getFloorFct = M.getOrInsertFunction(
        "floor", FunctionType::get(float4Ty, {float4Ty}, false));
    Coord = B.CreateCall(getFloorFct, {Coord});
    Coord = B.CreateFAdd(Coord, ConstantFP::get(float4Ty, 0.5));
  }

  return B.CreateFDiv(Coord, ImgDimFP);
}

bool isReadImage3DWithNonLiteralSampler(CallInst *call) {
  auto FI = Builtins::Lookup(call->getCalledFunction());
  switch (FI.getType()) {
  case Builtins::kReadImagef:
  case Builtins::kReadImagei:
  case Builtins::kReadImageui: {
    if (FI.getParameter(1).isSampler()) {
      Type *ImgTy = call->getOperand(0)->getType();
      auto sampler_call = dyn_cast<CallInst>(call->getOperand(1));
      bool literal_sampler =
          sampler_call &&
          (sampler_call->getCalledFunction()->getName().contains(
               TranslateSamplerInitializerFunction()) ||
           sampler_call->getCalledFunction()->getName().contains(
               LiteralSamplerFunction()));
      if (clspv::ImageDimensionality(ImgTy) == spv::Dim3D && !literal_sampler) {
        return true;
      }
    }
  } break;
  default:
    break;
  }
  return false;
}

} // namespace clspv