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Get SIMD Capabilities

Source: R/simd_info.R
simd_info.Rd

Reports the SIMD (Single Instruction Multiple Data) capabilities available in the current installation, for diagnostics and debugging.

Usage

simd_info()

Value

A list with the following components:

enabled

Logical indicating if SIMD is currently enabled

available

Logical indicating if SIMD support was compiled in

architecture

Character string describing the SIMD instruction set (e.g., "AVX2", "SSE4.2", "NEON")

batch_size_double

Integer number of doubles processed per SIMD operation

batch_size_float

Integer number of floats processed per SIMD operation

version

Character string describing the SIMD library in use

debug_build

Logical indicating the shared object was compiled without NDEBUG, i.e. by devtools::load_all() / pkgbuild::compile_dll(), which force -UNDEBUG -Wall -pedantic -g -O0. Such a build is not representative of normal operation and must not be used for timing comparisons; reinstall with R CMD INSTALL --preclean . to get optimised objects.

Details

The pladdrr package uses SIMD acceleration for computationally intensive operations like autocorrelation, windowing, and statistical computations. The effect varies by code path and platform; use [pladdrr_simd()] to toggle SIMD at runtime and compare a given workload directly.

Common SIMD instruction sets:

  • AVX2: 256-bit vectors (4 doubles or 8 floats) - Intel/AMD x86_64

  • SSE4.2: 128-bit vectors (2 doubles or 4 floats) - Older x86_64

  • NEON: 128-bit vectors (2 doubles or 4 floats) - ARM (Apple Silicon)

Set options(pladdrr.use_simd = FALSE) before loading the package to start in scalar mode, or use [pladdrr_simd()] after load for runtime A/B checks. The option is read during .onLoad.

Examples

# Check SIMD capabilities
info <- simd_info()
print(info)
#> $enabled
#> [1] TRUE
#> 
#> $available
#> [1] TRUE
#> 
#> $architecture
#> [1] "Generic"
#> 
#> $batch_size_double
#> [1] 2
#> 
#> $batch_size_float
#> [1] 4
#> 
#> $version
#> [1] "xsimd"
#> 
#> $debug_build
#> [1] FALSE
#> 

if (info$architecture == "AVX2") {
  message("AVX2 SIMD support detected")
}

# Disable SIMD temporarily for testing
pladdrr_simd(FALSE)
# ... run tests ...
pladdrr_simd(TRUE)