AMDGPUMachineFunction.h

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//===-- AMDGPUMachineFunctionInfo.h -------------------------------*- 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
//
//===----------------------------------------------------------------------===//
 
#ifndef LLVM_LIB_TARGET_AMDGPU_AMDGPUMACHINEFUNCTION_H
#define LLVM_LIB_TARGET_AMDGPU_AMDGPUMACHINEFUNCTION_H
 
#include "Utils/AMDGPUBaseInfo.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/GlobalVariable.h"
 
namespace llvm {
 
class AMDGPUSubtarget;
 
class AMDGPUMachineFunction : public MachineFunctionInfo {
  /// A map to keep track of local memory objects and their offsets within the
  /// local memory space.
  SmallDenseMap<const GlobalValue *, unsigned, 4> LocalMemoryObjects;
 
protected:
  uint64_t ExplicitKernArgSize = 0; // Cache for this.
  Align MaxKernArgAlign;        // Cache for this.
 
  /// Number of bytes in the LDS that are being used.
  uint32_t LDSSize = 0;
  uint32_t GDSSize = 0;
 
  /// Number of bytes in the LDS allocated statically. This field is only used
  /// in the instruction selector and not part of the machine function info.
  uint32_t StaticLDSSize = 0;
  uint32_t StaticGDSSize = 0;
 
  /// Align for dynamic shared memory if any. Dynamic shared memory is
  /// allocated directly after the static one, i.e., LDSSize. Need to pad
  /// LDSSize to ensure that dynamic one is aligned accordingly.
  /// The maximal alignment is updated during IR translation or lowering
  /// stages.
  Align DynLDSAlign;
 
  // Flag to check dynamic LDS usage by kernel.
  bool UsesDynamicLDS = false;
 
  uint32_t NumNamedBarriers = 0;
 
  // Kernels + shaders. i.e. functions called by the hardware and not called
  // by other functions.
  bool IsEntryFunction = false;
 
  // Entry points called by other functions instead of directly by the hardware.
  bool IsModuleEntryFunction = false;
 
  // Functions with the amdgpu_cs_chain or amdgpu_cs_chain_preserve CC.
  bool IsChainFunction = false;
 
  // Function may be memory bound.
  bool MemoryBound = false;
 
  // Kernel may need limited waves per EU for better performance.
  bool WaveLimiter = false;
 
  bool HasInitWholeWave = false;
 
public:
  AMDGPUMachineFunction(const Function &F, const AMDGPUSubtarget &ST);
 
  uint64_t getExplicitKernArgSize() const {
    return ExplicitKernArgSize;
  }
 
  Align getMaxKernArgAlign() const { return MaxKernArgAlign; }
 
  uint32_t getLDSSize() const {
    return LDSSize;
  }
 
  uint32_t getGDSSize() const {
    return GDSSize;
  }
 
  void recordNumNamedBarriers(uint32_t GVAddr, unsigned BarCnt) {
    NumNamedBarriers =
        std::max(NumNamedBarriers, ((GVAddr & 0x1ff) >> 4) + BarCnt - 1);
  }
  uint32_t getNumNamedBarriers() const { return NumNamedBarriers; }
 
  bool isEntryFunction() const {
    return IsEntryFunction;
  }
 
  bool isModuleEntryFunction() const { return IsModuleEntryFunction; }
 
  bool isChainFunction() const { return IsChainFunction; }
 
  // The stack is empty upon entry to this function.
  bool isBottomOfStack() const {
    return isEntryFunction() || isChainFunction();
  }
 
  bool isMemoryBound() const {
    return MemoryBound;
  }
 
  bool needsWaveLimiter() const {
    return WaveLimiter;
  }
 
  bool hasInitWholeWave() const { return HasInitWholeWave; }
  void setInitWholeWave() { HasInitWholeWave = true; }
 
  unsigned allocateLDSGlobal(const DataLayout &DL, const GlobalVariable &GV) {
    return allocateLDSGlobal(DL, GV, DynLDSAlign);
  }
 
  unsigned allocateLDSGlobal(const DataLayout &DL, const GlobalVariable &GV,
                             Align Trailing);
 
  static std::optional<uint32_t> getLDSKernelIdMetadata(const Function &F);
  static std::optional<uint32_t> getLDSAbsoluteAddress(const GlobalValue &GV);
 
  Align getDynLDSAlign() const { return DynLDSAlign; }
 
  void setDynLDSAlign(const Function &F, const GlobalVariable &GV);
 
  void setUsesDynamicLDS(bool DynLDS);
 
  bool isDynamicLDSUsed() const;
};
 
}
#endif