//===-- SPIRVSubtarget.h - SPIR-V Subtarget Information --------*- C++ -*--===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file declares the SPIR-V specific subclass of TargetSubtargetInfo.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_LIB_TARGET_SPIRV_SPIRVSUBTARGET_H
#define LLVM_LIB_TARGET_SPIRV_SPIRVSUBTARGET_H

#include "SPIRVCallLowering.h"
#include "SPIRVFrameLowering.h"
#include "SPIRVISelLowering.h"
#include "SPIRVInlineAsmLowering.h"
#include "SPIRVInstrInfo.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/CodeGen/GlobalISel/CallLowering.h"
#include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
#include "llvm/CodeGen/GlobalISel/LegalizerInfo.h"
#include "llvm/CodeGen/SelectionDAGTargetInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/TargetParser/Triple.h"

#define GET_SUBTARGETINFO_HEADER
#include "SPIRVGenSubtargetInfo.inc"

namespace llvm {
class StringRef;
class SPIRVTargetMachine;

class SPIRVSubtarget : public SPIRVGenSubtargetInfo {
public:
  // Enum for the SPIR-V environment: Kernel, Shader or Unknown.
  enum SPIRVEnvType { Kernel, Shader, Unknown };

private:
  const unsigned PointerSize;
  VersionTuple SPIRVVersion;
  VersionTuple OpenCLVersion;

  SmallSet<SPIRV::Extension::Extension, 4> AvailableExtensions;
  SmallSet<SPIRV::InstructionSet::InstructionSet, 4> AvailableExtInstSets;
  std::unique_ptr<SPIRVGlobalRegistry> GR;

  SPIRVInstrInfo InstrInfo;
  SPIRVFrameLowering FrameLowering;
  SPIRVTargetLowering TLInfo;
  Triple TargetTriple;
  SPIRVEnvType Env;

  // GlobalISel related APIs.
  std::unique_ptr<CallLowering> CallLoweringInfo;
  std::unique_ptr<RegisterBankInfo> RegBankInfo;
  std::unique_ptr<LegalizerInfo> Legalizer;
  std::unique_ptr<InstructionSelector> InstSelector;
  std::unique_ptr<InlineAsmLowering> InlineAsmInfo;

  // TODO: Initialise the available extensions, extended instruction sets
  // based on the environment settings.
  void initAvailableExtInstSets();
  void accountForAMDShaderTrinaryMinmax();

public:
  // This constructor initializes the data members to match that
  // of the specified triple.
  SPIRVSubtarget(const Triple &TT, const std::string &CPU,
                 const std::string &FS, const SPIRVTargetMachine &TM);
  SPIRVSubtarget &initSubtargetDependencies(StringRef CPU, StringRef FS);

  void initAvailableExtensions(
      const std::set<SPIRV::Extension::Extension> &AllowedExtIds);

  // Parses features string setting specified subtarget options.
  // The definition of this function is auto generated by tblgen.
  void ParseSubtargetFeatures(StringRef CPU, StringRef TuneCPU, StringRef FS);
  unsigned getPointerSize() const { return PointerSize; }
  unsigned getBound() const { return GR->getBound(); }
  bool canDirectlyComparePointers() const;
  void setEnv(SPIRVEnvType E) {
    if (E == Unknown)
      report_fatal_error("Unknown environment is not allowed.");
    if (Env != Unknown)
      report_fatal_error("Environment is already set.");

    Env = E;
  }
  SPIRVEnvType getEnv() const { return Env; }
  bool isKernel() const { return getEnv() == Kernel; }
  bool isShader() const { return getEnv() == Shader; }
  bool isLogicalSPIRV() const {
    return TargetTriple.getArch() == Triple::spirv;
  }
  bool isPhysicalSPIRV() const {
    return TargetTriple.getArch() == Triple::spirv32 ||
           TargetTriple.getArch() == Triple::spirv64;
  }
  const std::string &getTargetTripleAsStr() const { return TargetTriple.str(); }
  VersionTuple getSPIRVVersion() const { return SPIRVVersion; };
  bool isAtLeastSPIRVVer(VersionTuple VerToCompareTo) const;
  bool isAtLeastOpenCLVer(VersionTuple VerToCompareTo) const;
  // TODO: implement command line args or other ways to determine this.
  bool hasOpenCLFullProfile() const { return true; }
  bool hasOpenCLImageSupport() const { return true; }
  const SmallSet<SPIRV::Extension::Extension, 4> &
  getAllAvailableExtensions() const {
    return AvailableExtensions;
  }
  bool canUseExtension(SPIRV::Extension::Extension E) const;
  bool canUseExtInstSet(SPIRV::InstructionSet::InstructionSet E) const;
  SPIRV::InstructionSet::InstructionSet getPreferredInstructionSet() const;

  SPIRVGlobalRegistry *getSPIRVGlobalRegistry() const { return GR.get(); }

  const CallLowering *getCallLowering() const override {
    return CallLoweringInfo.get();
  }
  const RegisterBankInfo *getRegBankInfo() const override {
    return RegBankInfo.get();
  }
  const LegalizerInfo *getLegalizerInfo() const override {
    return Legalizer.get();
  }
  InstructionSelector *getInstructionSelector() const override {
    return InstSelector.get();
  }
  const InlineAsmLowering *getInlineAsmLowering() const override {
    return InlineAsmInfo.get();
  }
  const SPIRVInstrInfo *getInstrInfo() const override { return &InstrInfo; }
  const SPIRVFrameLowering *getFrameLowering() const override {
    return &FrameLowering;
  }
  const SPIRVTargetLowering *getTargetLowering() const override {
    return &TLInfo;
  }
  const SPIRVRegisterInfo *getRegisterInfo() const override {
    return &InstrInfo.getRegisterInfo();
  }

  static bool classof(const TargetSubtargetInfo *ST) {
    return ST->getTargetTriple().isSPIRV();
  }

  static constexpr unsigned MaxLegalAddressSpace = 6;

  // Adds known SPIR-V extensions to the global list of allowed extensions that
  // SPIRVSubtarget module owns as
  // cl::opt<std::set<SPIRV::Extension::Extension>, ...> global variable.
  static void
  addExtensionsToClOpt(const std::set<SPIRV::Extension::Extension> &AllowList);
};
} // namespace llvm

#endif // LLVM_LIB_TARGET_SPIRV_SPIRVSUBTARGET_H