Use specific build-target for ARM/NEON routines

libs/ardour/ardour/mix.h

@@ -70,8 +70,8 @@ LIBARDOUR_API void  veclib_mix_buffers_no_gain       (ARDOUR::Sample * dst, cons
 
 #endif
 
+#if defined ARM_NEON_SUPPORT
 /* Optimized NEON functions */
-#if defined(__arm__) && !defined(__APPLE__)
 extern "C" {
 	LIBARDOUR_API float arm_neon_compute_peak          (const float * buf, uint32_t nsamples, float current);
 	LIBARDOUR_API void  arm_neon_apply_gain_to_buffer  (float * buf, uint32_t nframes, float gain);

libs/ardour/globals.cc

@@ -217,7 +217,7 @@ setup_hardware_optimization (bool try_optimization)
 			generic_mix_functions = false;
 		}
 
-#elif defined(__arm__) && !defined(__APPLE__)
+#elif defined ARM_NEON_SUPPORT
 		/* Use NEON routines */
 		do {
 			compute_peak          = arm_neon_compute_peak;

libs/ardour/wscript

@@ -467,7 +467,6 @@ def build(bld):
     avx_sources = []
 
     if Options.options.fpu_optimization:
-        obj.source += ['arm_neon_functions.cc']
         if (bld.env['build_target'] == 'i386' or bld.env['build_target'] == 'i686'):
             obj.source += [ 'sse_functions_xmm.cc', 'sse_functions.s', ]
             avx_sources = [ 'sse_functions_avx_linux.cc' ]
@@ -482,6 +481,9 @@ def build(bld):
                         obj.source += [ 'sse_functions_xmm.cc' ]
                         obj.source += [ 'sse_functions_64bit_win.s',  'sse_avx_functions_64bit_win.s' ]
                         avx_sources = [ 'sse_functions_avx.cc' ]
+        elif bld.env['build_target'] == 'armhf' or bld.env['build_target'] == 'aarch64':
+            obj.source += ['arm_neon_functions.cc']
+            obj.defines += [ 'ARM_NEON_SUPPORT' ]
 
         if avx_sources:
             # as long as we want to use AVX intrinsics in this file,

wscript

@@ -474,6 +474,9 @@ int main() { return 0; }''',
         #
         compiler_flags.append ('-U__STRICT_ANSI__')
 
+    if conf.env['build_target'] == 'armhf' or conf.env['build_target'] == 'aarch64':
+        conf.define('ARM_NEON_SUPPORT', 1)
+
     if opt.use_libcpp or conf.env['build_host'] in [ 'el_capitan', 'sierra', 'high_sierra', 'mojave', 'catalina' ]:
        cxx_flags.append('--stdlib=libc++')
        linker_flags.append('--stdlib=libc++')