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/*! \file
    \brief Grid dependent control (GDC) helpers for programmatic dependent launches (PDL).
*/

#pragma once

#include "cute/arch/cluster_sm90.hpp"
#include "cutlass/arch/barrier.h"
#include "cutlass/conv/dispatch_policy.hpp"
#include "cutlass/gemm/dispatch_policy.hpp"

#ifndef CUTLASS_GDC_ENABLED
  #if (defined(CUTLASS_ENABLE_GDC_FOR_SM90) && \
     __CUDACC_VER_MAJOR__ >= 12 && \
     defined(__CUDA_ARCH__) && __CUDA_ARCH__ >= 900 && defined(__CUDA_ARCH_FEAT_SM90_ALL))
    #define CUTLASS_GDC_ENABLED
  #endif
#endif

namespace cutlass {
namespace arch {

// Issuing the launch_dependents instruction hints a dependent kernel to launch earlier
// launch_dependents doesn't impact the functionality but the performance:
// Launching a dependent kernel too early can compete with current kernels,
// while launching too late can lead to a long latency.
CUTLASS_DEVICE
void launch_dependent_grids() {
#if (defined(CUTLASS_GDC_ENABLED))
  asm volatile("griddepcontrol.launch_dependents;");
#endif
}

// Issuing the griddepcontrol.wait instruction enforces no global memory access
// prior to this istruction. This ensures the correctness of global memory access
// when launching a dependent kernel earlier.
CUTLASS_DEVICE
void wait_on_dependent_grids() {
#if (defined(CUTLASS_GDC_ENABLED))
  asm volatile("griddepcontrol.wait;");
#endif
}

// Enable kernel-level query regarding whether the GDC feature is turned on
#if (defined(CUTLASS_GDC_ENABLED))
static constexpr bool IsGdcGloballyEnabled = true;
#else
static constexpr bool IsGdcGloballyEnabled = false;
#endif


} // namespace arch
} // namespace cutlass
