llvm/llvm/lib/Target/AMDGPU/AMDGPUSetWavePriority.cpp

//===- AMDGPUSetWavePriority.cpp - Set wave priority ----------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
/// \file
/// Pass to temporarily raise the wave priority beginning the start of
/// the shader function until its last VMEM instructions to allow younger
/// waves to issue their VMEM instructions as well.
//
//===----------------------------------------------------------------------===//

#include "AMDGPU.h"
#include "GCNSubtarget.h"
#include "MCTargetDesc/AMDGPUMCTargetDesc.h"
#include "SIInstrInfo.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/Allocator.h"

usingnamespacellvm;

#define DEBUG_TYPE …

static cl::opt<unsigned> DefaultVALUInstsThreshold(
    "amdgpu-set-wave-priority-valu-insts-threshold",
    cl::desc("VALU instruction count threshold for adjusting wave priority"),
    cl::init(100), cl::Hidden);

namespace {

struct MBBInfo { … };

MBBInfoSet;

class AMDGPUSetWavePriority : public MachineFunctionPass { … };

} // End anonymous namespace.

INITIALIZE_PASS(…)

char AMDGPUSetWavePriority::ID = …;

FunctionPass *llvm::createAMDGPUSetWavePriorityPass() { … }

MachineInstr *
AMDGPUSetWavePriority::BuildSetprioMI(MachineBasicBlock &MBB,
                                      MachineBasicBlock::iterator I,
                                      unsigned priority) const { … }

// Checks that for every predecessor Pred that can reach a VMEM load,
// none of Pred's successors can reach a VMEM load.
static bool CanLowerPriorityDirectlyInPredecessors(const MachineBasicBlock &MBB,
                                                   MBBInfoSet &MBBInfos) { … }

static bool isVMEMLoad(const MachineInstr &MI) { … }

bool AMDGPUSetWavePriority::runOnMachineFunction(MachineFunction &MF) { … }