1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
# @synopsis AX_CHECK_ARM_NEON
#
# Does the machine support the ARM NEON instruction set?
# @version 1.01 Feb 11 2013
# @author Steve Underwood
#
# Permission to use, copy, modify, distribute, and sell this file for any
# purpose is hereby granted without fee, provided that the above copyright
# and this permission notice appear in all copies. No representations are
# made about the suitability of this software for any purpose. It is
# provided "as is" without express or implied warranty.
AC_DEFUN([AX_CHECK_ARM_NEON],
[AC_CACHE_CHECK([if $1 supports the ARM NEON instructions set],
ac_cv_symbol_arm_neon,
[# Initialize to unknown
ac_cv_symbol_arm_neon="no"
case "${ax_cv_c_compiler_vendor}" in
gnu)
save_CFLAGS="${CFLAGS}"
CFLAGS="${CFLAGS} -mfpu=neon -mfloat-abi=hard"
AC_RUN_IFELSE(
[AC_LANG_PROGRAM(
[
#include <inttypes.h>
#include <arm_neon.h>
int32x4_t testfunc(int16_t *a, int16_t *b)
{
return vmull_s16(vld1_s16(a), vld1_s16(b));
}
],
[
volatile int32x4_t z;
int16_t x[[8]];
int16_t y[[8]];
z = testfunc(x, y);
]
)],
[AC_MSG_RESULT([yes])
COMP_VENDOR_CFLAGS="-mfpu=neon $COMP_VENDOR_CFLAGS"
COMP_VENDOR_CXXFLAGS="-mfpu=neon $COMP_VENDOR_CXXFLAGS"
ac_cv_symbol_arm_neon="yes"],
[AC_MSG_RESULT([no])],
dnl Assume "no" if cross-compiling
[AC_MSG_RESULT([no])]
)
CFLAGS="${save_CFLAGS}"
;;
esac])
AS_IF([test AS_VAR_GET(ac_cv_symbol_arm_neon) = yes], [$2], [$3])[]dnl
]) # AX_CHECK_ARM_NEON
|
