GpuKernelLaunch

Launches a GPU kernel.

Declaration

Syntax

GpuKernelLaunch(symbol kernel, expr grid_size, expr block_size,
    call_arg* args)

Arguments

Argument

Description

kernel

the GpuKernelFunction to run.

grid_size

the number of blocks to launch.

block_size

the number of threads per block.

args

the arguments passed to every thread.

Return values

None.

Description

A launch is not a call: it starts grid_size * block_size threads and, unless the backend says otherwise, returns without waiting for them. GpuSync is what waits.

The execution configuration is part of the node rather than of the kernel, because the same kernel is normally launched with different sizes.

Examples

(GpuKernelLaunch
  :kernel (SymbolRef 1 "zero")
  :grid_size (IntegerConstant
    :n 1
    :type (Integer
      :kind 4
    )
    :intboz_type :Decimal
  )
  :block_size (IntegerConstant
    :n 256
    :type (Integer
      :kind 4
    )
    :intboz_type :Decimal
  )
  :args [
    (call_arg
      :value (Var
        :v (SymbolRef 2 "a")
      )
    )
  ]
)

It comes from this complete ASR text document:

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See Also

GpuKernelFunction, GpuSync, GpuThreadIndex