Package {RsimdDispatch}

Title: Runtime 'SIMD' Dispatch Templates for 'C' Code in 'R' Packages
Version: 0.1.1
Description: Provides templates and a working example for runtime Single Instruction Multiple Data ('SIMD') dispatch in 'C' code used by 'R' packages. Packages can stage scalar and architecture-specific kernel objects during configuration, then select a compiled and CPU-supported implementation at runtime through guarded function pointers. The package also vendors the header-only 'SIMDe' library for downstream packages through the 'LinkingTo' field.
License: GPL-2 | GPL-3 [expanded from: GPL (≥ 2)]
Copyright: See inst/AUTHORS and inst/LICENCE.note for bundled SIMDe authorship and licensing details.
SystemRequirements: GNU make
Suggests: bench, knitr, rmarkdown, tinytest
VignetteBuilder: knitr
Encoding: UTF-8
RoxygenNote: 7.3.3
URL: https://github.com/sounkou-bioinfo/RsimdDispatch, https://sounkou-bioinfo.github.io/RsimdDispatch/
BugReports: https://github.com/sounkou-bioinfo/RsimdDispatch/issues
NeedsCompilation: yes
Packaged: 2026-05-28 20:43:01 UTC; sounkoutoure
Author: Sounkou Mahamane Toure [aut, cre], Evan Nemerson [cph] (SIMDe copyright holder), SIMDe contributors [ctb] (Contributors to the bundled SIMDe header library)
Maintainer: Sounkou Mahamane Toure <sounkoutoure@gmail.com>
Repository: CRAN
Date/Publication: 2026-06-01 14:30:02 UTC

Count non-zero bytes with the selected SIMD backend

Description

Demonstration kernel for the runtime dispatch template. count_nonzero() counts bytes that are not 00 in a raw vector using the currently selected backend. The default backend is "auto", which selects the best compiled backend supported by the current CPU/runtime.

Usage

count_nonzero(x)

Arguments

x

A raw vector.

Value

A numeric scalar count.

Examples

count_nonzero(as.raw(c(0, 1, 0, 2)))

Report the currently selected SIMD backend

Description

Report the currently selected SIMD backend

Usage

simd_backend()

Value

A character scalar naming the selected backend.

Examples

simd_backend()

Configure an R package for C runtime SIMD dispatch

Description

use_simd_dispatch() copies the dispatch scaffold into an R package and performs the package-name and C-prefix substitutions needed for a working package. It writes package files, updates DESCRIPTION, .Rbuildignore, and .gitignore, and returns the copied paths invisibly.

Usage

simd_dispatch_template_path()

use_simd_dispatch(
  path = ".",
  pkg = NULL,
  prefix = NULL,
  overwrite = FALSE,
  quiet = FALSE
)

Arguments

path

Package root where the template should be copied.

pkg

R package name. If NULL, the name is read from DESCRIPTION.

prefix

C symbol prefix used to replace rsd_ in the copied sources. The default is a sanitized lowercase package name.

overwrite

Whether to overwrite existing files.

quiet

Whether to suppress progress messages.

Value

Invisibly returns copied file paths.

Developer utility

This function is intended for package authors. It is not needed at runtime by users of packages that already include generated dispatch code.

Examples

simd_dispatch_template_path()

Report runtime SIMD dispatch diagnostics

Description

Returns the requested backend, selected backend, compiled backends, CPU-supported backends, SIMDe-native backends, target information, and SIMDe provenance compiled into the shared library. Calling this initializes the lazy auto-dispatch selection if it has not already been initialized.

Usage

simd_info()

Value

A named list of dispatch and CPU feature diagnostics. Backend-set entries are character vectors, not comma-separated strings.

Examples

names(simd_info())

Select the runtime SIMD backend

Description

Select the backend used by subsequent calls to count_nonzero(). RsimdDispatch keeps all compiled variants in one shared object and switches guarded function pointers. This makes same-process benchmarking possible.

Usage

simd_set_backend(
  backend = c("auto", "scalar", "sse2", "sse41", "avx2", "avx512", "neon")
)

Arguments

backend

One of "auto", "scalar", "sse2", "sse41", "avx2", "avx512", or "neon".

Value

The selected backend, invisibly. For "auto", this is the backend chosen from the compiled and CPU-supported set.

Examples

old <- simd_backend()
simd_set_backend("scalar")
simd_set_backend("auto")

Report vendored SIMDe provenance

Description

simde_info() reports the version, upstream repository, pinned commit, and commit date for the bundled header-only SIMDe library.

Usage

simde_info()

Value

A named list of character scalars describing the vendored SIMDe copy.

Examples

simde_info()[c("version", "commit")]