build: add configure checks for minisketch

AC_DEFINE'd values won't be passed down to minisketch because it does not
use bitcoin-config.h. Thus we need a way to know if we should manually add
defines for minisketch files.

Author: theuni

configure.ac

@@ -470,6 +470,24 @@ AX_CHECK_COMPILE_FLAG([-msse4.1],[[SSE41_CXXFLAGS="-msse4.1"]],,[[$CXXFLAG_WERRO
 AX_CHECK_COMPILE_FLAG([-mavx -mavx2],[[AVX2_CXXFLAGS="-mavx -mavx2"]],,[[$CXXFLAG_WERROR]])
 AX_CHECK_COMPILE_FLAG([-msse4 -msha],[[SHANI_CXXFLAGS="-msse4 -msha"]],,[[$CXXFLAG_WERROR]])
 
+enable_clmul=
+AX_CHECK_COMPILE_FLAG([-mpclmul], [enable_clmul=yes], [], [$CXXFLAG_WERROR], [AC_LANG_PROGRAM([
+  #include <stdint.h>
+  #include <x86intrin.h>
+], [
+  __m128i a = _mm_cvtsi64_si128((uint64_t)7);
+  __m128i b = _mm_clmulepi64_si128(a, a, 37);
+  __m128i c = _mm_srli_epi64(b, 41);
+  __m128i d = _mm_xor_si128(b, c);
+  uint64_t e = _mm_cvtsi128_si64(d);
+  return e == 0;
+])])
+
+if test x$enable_clmul = xyes; then
+  CLMUL_CXXFLAGS="-mpclmul"
+  AC_DEFINE(HAVE_CLMUL, 1, [Define this symbol if clmul instructions can be used])
+fi
+
 TEMP_CXXFLAGS="$CXXFLAGS"
 CXXFLAGS="$CXXFLAGS $SSE42_CXXFLAGS"
 AC_MSG_CHECKING(for SSE4.2 intrinsics)
@@ -950,19 +968,20 @@ AC_CHECK_DECLS([bswap_16, bswap_32, bswap_64],,,
                  #endif])
 
 AC_MSG_CHECKING(for __builtin_clzl)
+
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[ ]], [[
  (void) __builtin_clzl(0);
   ]])],
- [ AC_MSG_RESULT(yes); AC_DEFINE(HAVE_BUILTIN_CLZL, 1, [Define this symbol if you have __builtin_clzl])],
- [ AC_MSG_RESULT(no)]
+ [ AC_MSG_RESULT(yes); have_clzl=yes; AC_DEFINE(HAVE_BUILTIN_CLZL, 1, [Define this symbol if you have __builtin_clzl])],
+ [ AC_MSG_RESULT(no); have_clzl=no;]
 )
 
 AC_MSG_CHECKING(for __builtin_clzll)
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[ ]], [[
   (void) __builtin_clzll(0);
   ]])],
- [ AC_MSG_RESULT(yes); AC_DEFINE(HAVE_BUILTIN_CLZLL, 1, [Define this symbol if you have __builtin_clzll])],
- [ AC_MSG_RESULT(no)]
+ [ AC_MSG_RESULT(yes); have_clzll=yes; AC_DEFINE(HAVE_BUILTIN_CLZLL, 1, [Define this symbol if you have __builtin_clzll])],
+ [ AC_MSG_RESULT(no); have_clzll=no;]
 )
 
 dnl Check for malloc_info (for memory statistics information in getmemoryinfo)
@@ -1763,6 +1782,10 @@ AM_CONDITIONAL([WORDS_BIGENDIAN],[test x$ac_cv_c_bigendian = xyes])
 AM_CONDITIONAL([USE_NATPMP],[test x$use_natpmp = xyes])
 AM_CONDITIONAL([USE_UPNP],[test x$use_upnp = xyes])
 
+dnl for minisketch
+AM_CONDITIONAL([ENABLE_CLMUL],[test x$enable_clmul = xyes])
+AM_CONDITIONAL([HAVE_CLZ],[test x$have_clzl$have_clzll = xyesyes])
+
 AC_DEFINE(CLIENT_VERSION_MAJOR, _CLIENT_VERSION_MAJOR, [Major version])
 AC_DEFINE(CLIENT_VERSION_MINOR, _CLIENT_VERSION_MINOR, [Minor version])
 AC_DEFINE(CLIENT_VERSION_BUILD, _CLIENT_VERSION_BUILD, [Version Build])
@@ -1806,6 +1829,7 @@ AC_SUBST(SANITIZER_CXXFLAGS)
 AC_SUBST(SANITIZER_LDFLAGS)
 AC_SUBST(SSE42_CXXFLAGS)
 AC_SUBST(SSE41_CXXFLAGS)
+AC_SUBST(CLMUL_CXXFLAGS)
 AC_SUBST(AVX2_CXXFLAGS)
 AC_SUBST(SHANI_CXXFLAGS)
 AC_SUBST(ARM_CRC_CXXFLAGS)