add fftw3 patch for neon as seen in this source repository local PR FFTW/fftw3#275 that will never be merged

Author: michael-schollerer

ports/fftw3/neon.patch

@@ -0,0 +1,73 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index db20caa7..48e724f3 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -25,6 +25,7 @@ option (ENABLE_SSE "Compile with SSE instruction set support" OFF)
+ option (ENABLE_SSE2 "Compile with SSE2 instruction set support" OFF)
+ option (ENABLE_AVX "Compile with AVX instruction set support" OFF)
+ option (ENABLE_AVX2 "Compile with AVX2 instruction set support" OFF)
++option (ENABLE_NEON "Compile with NEON instruction set support" OFF)
+ 
+ option (DISABLE_FORTRAN "Disable Fortran wrapper routines" OFF)
+ 
+@@ -203,9 +204,20 @@ if (ENABLE_AVX2)
+   endforeach ()
+ endif ()
+ 
++if (ENABLE_NEON)
++  if (ENABLE_LONG_DOUBLE)
++    message (FATAL_ERROR "NEON only works in single or double precision, please disable long double support")
++  endif ()
++  if (ENABLE_QUAD_PRECISION)
++    message (FATAL_ERROR "NEON only works in single or double precision, please disable quad precision support")
++  endif ()
++  set (HAVE_NEON TRUE)
++endif ()
++
+ if (HAVE_SSE2 OR HAVE_AVX)
+   set (HAVE_SIMD TRUE)
+ endif ()
++
+ file(GLOB           fftw_api_SOURCE                 api/*.c             api/*.h)
+ file(GLOB           fftw_dft_SOURCE                 dft/*.c             dft/*.h)
+ file(GLOB           fftw_dft_scalar_SOURCE          dft/scalar/*.c      dft/scalar/*.h)
+@@ -215,6 +227,7 @@ file(GLOB           fftw_dft_simd_SOURCE            dft/simd/*.c        dft/simd
+ file(GLOB           fftw_dft_simd_sse2_SOURCE       dft/simd/sse2/*.c   dft/simd/sse2/*.h)
+ file(GLOB           fftw_dft_simd_avx_SOURCE        dft/simd/avx/*.c    dft/simd/avx/*.h)
+ file(GLOB           fftw_dft_simd_avx2_SOURCE       dft/simd/avx2/*.c   dft/simd/avx2/*.h dft/simd/avx2-128/*.c   dft/simd/avx2-128/*.h)
++file(GLOB           fftw_dft_simd_neon_SOURCE       dft/simd/neon/*.c   dft/simd/neon/*.h)
+ file(GLOB           fftw_kernel_SOURCE              kernel/*.c          kernel/*.h)
+ file(GLOB           fftw_rdft_SOURCE                rdft/*.c            rdft/*.h)
+ file(GLOB           fftw_rdft_scalar_SOURCE         rdft/scalar/*.c     rdft/scalar/*.h)
+@@ -230,6 +243,7 @@ file(GLOB           fftw_rdft_simd_SOURCE           rdft/simd/*.c       rdft/sim
+ file(GLOB           fftw_rdft_simd_sse2_SOURCE      rdft/simd/sse2/*.c  rdft/simd/sse2/*.h)
+ file(GLOB           fftw_rdft_simd_avx_SOURCE       rdft/simd/avx/*.c   rdft/simd/avx/*.h)
+ file(GLOB           fftw_rdft_simd_avx2_SOURCE      rdft/simd/avx2/*.c  rdft/simd/avx2/*.h rdft/simd/avx2-128/*.c  rdft/simd/avx2-128/*.h)
++file(GLOB           fftw_rdft_simd_neon_SOURCE      rdft/simd/neon/*.c  rdft/simd/neon/*.h)
+ 
+ file(GLOB           fftw_reodft_SOURCE              reodft/*.c          reodft/*.h)
+ file(GLOB           fftw_simd_support_SOURCE        simd-support/*.c    simd-support/*.h)
+@@ -283,6 +297,10 @@ if (HAVE_AVX2)
+   list (APPEND SOURCEFILES ${fftw_dft_simd_avx2_SOURCE} ${fftw_rdft_simd_avx2_SOURCE})
+ endif ()
+ 
++if (HAVE_NEON)
++  list (APPEND SOURCEFILES ${fftw_dft_simd_neon_SOURCE} ${fftw_rdft_simd_neon_SOURCE})
++endif ()
++
+ set (FFTW_VERSION 3.3.10)
+ 
+ set (PREC_SUFFIX)
+ diff --git a/cmake.config.h.in b/cmake.config.h.in
+index 1f4c5055..8c61b38f 100644
+--- a/cmake.config.h.in
++++ b/cmake.config.h.in
+@@ -211,7 +211,7 @@
+ /* #undef HAVE_MPI */
+ 
+ /* Define to enable ARM NEON optimizations. */
+-/* #undef HAVE_NEON */
++#cmakedefine HAVE_NEON 1
+ 
+ /* Define if OpenMP is enabled */
+ #cmakedefine HAVE_OPENMP

ports/fftw3/portfile.cmake

@@ -14,6 +14,7 @@ vcpkg_extract_source_archive(
         fix-openmp.patch
         install-subtargets.patch
         fix-wrong-version.patch # https://github.com/FFTW/fftw3/commit/0842f00ae6b6e1f3aade155bc0edd17a7313fa6a
+        neon.patch # add neon
 )
 
 vcpkg_check_features(
@@ -27,12 +28,13 @@ vcpkg_check_features(
         avx     ENABLE_AVX
         sse2    ENABLE_SSE2
         sse     ENABLE_SSE
+        neon    ENABLE_NEON # add neon
 )
 
 set(package_names  fftw3 fftw3f fftw3l)
 set(fftw3_options  "")
 set(fftw3f_options -DENABLE_FLOAT=ON)
-set(fftw3l_options -DENABLE_LONG_DOUBLE=ON -DENABLE_AVX2=OFF -DENABLE_AVX=OFF -DENABLE_SSE2=OFF)
+set(fftw3l_options -DENABLE_LONG_DOUBLE=ON -DENABLE_AVX2=OFF -DENABLE_AVX=OFF -DENABLE_SSE2=OFF -DENABLE_NEON=OFF)
 
 foreach(package_name IN LISTS package_names)
     message(STATUS "${package_name}...")

ports/fftw3/vcpkg.json

@@ -35,6 +35,10 @@
       "description": "Builds part of the library with sse2, sse",
       "supports": "!arm"
     },
+    "neon": {
+      "description": "Builds part of the library with neon",
+      "supports": "arm"
+    },
     "threads": {
       "description": "Enable threads in fftw3"
     }