add avx_enabled()

NAMESPACE

@@ -8,6 +8,7 @@ S3method(plot,fcwtr_scalogram)
 S3method(print,fcwtr_scalogram)
 S3method(rbind,fcwtr_scalogram)
 S3method(tibble::as_tibble,fcwtr_scalogram)
+export(avx_enabled)
 export(du)
 export(fcwt)
 export(fcwt_batch)

NEWS.md

@@ -18,7 +18,7 @@
 
 -   add more convenience S3 methods: `print()`, `[]`, `as.matrix()`, `rbind()`, `as_tibble()`.
 
--   `openmp_enabled()`: new function to check for OpenMP support.
+-   `openmp_enabled()`/`avx_enabled()` new function to check for system OpenMP/AVX support.
 
 -   add a [package logo](https://lschneiderbauer.github.io/fCWTr/logo.svg)
 

R/cpp11.R

@@ -4,6 +4,10 @@ has_openmp <- function() {
   .Call(`_fCWTr_has_openmp`)
 }
 
+has_avx <- function() {
+  .Call(`_fCWTr_has_avx`)
+}
+
 fcwt_raw <- function(signal, fs, f0, f1, fn, sigma, nthreads, scaletype, optplans, abs) {
   .Call(`_fCWTr_fcwt_raw`, signal, fs, f0, f1, fn, sigma, nthreads, scaletype, optplans, abs)
 }

R/sys_support.R

@@ -0,0 +1,58 @@
+
+#' Check for OpenMP support
+#'
+#' This function checks if OpenMP support is enabled. It is responsible for
+#' the multithreading capabilities of [fcwt()]. If OpenMP is not enabled
+#' the parameter `n_threads` of [fcwt()] is ignored.
+#'
+#' @details
+#' OpenMP can be used by the underlying fCWT library if
+#' * the fftw library on your platform was compiled with OpenMP support and
+#' * the fCWTr package itself was compiled with OpenMP support.
+#'
+#' When using pre-built package binaries (like it is typical when you are using
+#' R on Windows), it depends on the (CRAN) build server whether or not
+#' these conditions are met. They cannot be influenced by the package author.
+#'
+#' If the user is building the R package yourself, the user needs to make sure
+#' that the fftw library on her platform are built with OpenMP support.
+#' The fCWTr package is configured to use OpenMP if fftw-OpenMP support is
+#' available.
+#'
+#' @return ( `TRUE` | `FALSE` )
+#'  Returns `TRUE` if OpenMP support is enabled, `FALSE` otherwise.
+#'
+#' @examples
+#' openmp_enabled()
+#'
+#' @export
+#' @concept sys_support
+openmp_enabled <- function() {
+  has_openmp()
+}
+
+
+#' Check for AVX instruction set support
+#'
+#' This function checks if fCWTr was compiled with AVX instruction set support.
+#' AVX instructions need to be supported by the users' CPU in order for this
+#' to work.
+#'
+#' @details
+#' By default, most compiler setups do not make use of AVX to increase
+#' portability of the binary. If you are an R user that has a CPU supporting
+#' AVX and want to make use of it, you might need to manually enable compiler
+#' flags to let R know about it, and install the package from source
+#' (so that it gets compiled on your machine).
+#'
+#' @return ( `TRUE` | `FALSE` )
+#'  Returns `TRUE` if AVX support is enabled, `FALSE` otherwise.
+#'
+#' @examples
+#' avx_enabled()
+#'
+#' @export
+#' @concept sys_support
+avx_enabled <- function() {
+  has_avx()
+}

_pkgdown.yml

@@ -21,9 +21,10 @@ reference:
   - print.fcwtr_scalogram
   - plot.fcwtr_scalogram
   - autoplot.fcwtr_scalogram
-- title: "Multithreading support"
+- title: "System support"
+  desc: "Helper functions that let you check if your platform provides OpenMP or AVX support."
   contents:
-  - openmp_enabled
+  - has_concept("sys_support")
 - title: "Sample data"
   desc: >
     Sample signal data mainly used to generate examples. The signals consist

src/cpp11.cpp

@@ -13,6 +13,13 @@ extern "C" SEXP _fCWTr_has_openmp() {
   END_CPP11
 }
 // interface_fcwt.cpp
+cpp11::r_bool has_avx();
+extern "C" SEXP _fCWTr_has_avx() {
+  BEGIN_CPP11
+    return cpp11::as_sexp(has_avx());
+  END_CPP11
+}
+// interface_fcwt.cpp
 std::vector<double> fcwt_raw(std::vector<double> signal, int fs, double f0, double f1, int fn, double sigma, int nthreads, bool scaletype, bool optplans, bool abs);
 extern "C" SEXP _fCWTr_fcwt_raw(SEXP signal, SEXP fs, SEXP f0, SEXP f1, SEXP fn, SEXP sigma, SEXP nthreads, SEXP scaletype, SEXP optplans, SEXP abs) {
   BEGIN_CPP11
@@ -23,6 +30,7 @@ extern "C" SEXP _fCWTr_fcwt_raw(SEXP signal, SEXP fs, SEXP f0, SEXP f1, SEXP fn,
 extern "C" {
 static const R_CallMethodDef CallEntries[] = {
     {"_fCWTr_fcwt_raw",   (DL_FUNC) &_fCWTr_fcwt_raw,   10},
+    {"_fCWTr_has_avx",    (DL_FUNC) &_fCWTr_has_avx,     0},
     {"_fCWTr_has_openmp", (DL_FUNC) &_fCWTr_has_openmp,  0},
     {NULL, NULL, 0}
 };

src/interface_fcwt.cpp

@@ -28,6 +28,15 @@ cpp11::r_bool has_openmp() {
   #endif
 }
 
+[[cpp11::register]]
+cpp11::r_bool has_avx() {
+  #ifdef AVX
+    return(false);
+  #else
+    return(true);
+  #endif
+}
+
 [[cpp11::register]]
 std::vector<double> fcwt_raw(
     std::vector<double> signal,

tests/testthat/test-sys_support.R

@@ -0,0 +1,11 @@
+test_that("openmp_enabled() works", {
+  expect_true(
+    openmp_enabled() == TRUE |  openmp_enabled() == FALSE
+  )
+})
+
+test_that("avx_enabled() works", {
+  expect_true(
+    avx_enabled() == TRUE |  avx_enabled() == FALSE
+  )
+})