@@ -2536,7 +2536,13 @@ config_host_data.set('CONFIG_ATOMIC64', cc.links('''
return 0;
}'''))
-has_int128 = cc.links('''
+has_int128_type = cc.compiles('''
+ __int128_t a;
+ __uint128_t b;
+ int main(void) { b = a; }''')
+config_host_data.set('CONFIG_INT128_TYPE', has_int128_type)
+
+has_int128 = has_int128_type and cc.links('''
__int128_t a;
__uint128_t b;
int main (void) {
@@ -2545,10 +2551,9 @@ has_int128 = cc.links('''
a = a * a;
return 0;
}''')
-
config_host_data.set('CONFIG_INT128', has_int128)
-if has_int128
+if has_int128_type
# "do we have 128-bit atomics which are handled inline and specifically not
# via libatomic". The reason we can't use libatomic is documented in the
# comment starting "GCC is a house divided" in include/qemu/atomic128.h.
@@ -2557,7 +2562,7 @@ if has_int128
# __alignof(unsigned __int128) for the host.
atomic_test_128 = '''
int main(int ac, char **av) {
- unsigned __int128 *p = __builtin_assume_aligned(av[ac - 1], 16);
+ __uint128_t *p = __builtin_assume_aligned(av[ac - 1], 16);
p[1] = __atomic_load_n(&p[0], __ATOMIC_RELAXED);
__atomic_store_n(&p[2], p[3], __ATOMIC_RELAXED);
__atomic_compare_exchange_n(&p[4], &p[5], p[6], 0, __ATOMIC_RELAXED, __ATOMIC_RELAXED);
@@ -2579,7 +2584,7 @@ if has_int128
config_host_data.set('CONFIG_CMPXCHG128', cc.links('''
int main(void)
{
- unsigned __int128 x = 0, y = 0;
+ __uint128_t x = 0, y = 0;
__sync_val_compare_and_swap_16(&x, y, x);
return 0;
}
@@ -481,7 +481,7 @@ static inline void bswap128s(Int128 *s)
* a possible structure and the native types. Ease parameter passing
* via use of the transparent union extension.
*/
-#ifdef CONFIG_INT128
+#ifdef CONFIG_INT128_TYPE
typedef union {
__uint128_t u;
__int128_t i;
@@ -489,6 +489,6 @@ typedef union {
} Int128Alias __attribute__((transparent_union));
#else
typedef Int128 Int128Alias;
-#endif /* CONFIG_INT128 */
+#endif /* CONFIG_INT128_TYPE */
#endif /* INT128_H */
Older versions of clang have missing runtime functions for arithmetic with -fsanitize=undefined (see 464e3671f9d5c), so we cannot use __int128_t for implementing Int128. But __int128_t is present, data movement works, and can be use for atomic128. Probe for both CONFIG_INT128_TYPE and CONFIG_INT128, adjust qemu/int128.h to define Int128Alias if CONFIG_INT128_TYPE, and adjust the meson probe for atomics to use has_int128_type. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- meson.build | 15 ++++++++++----- include/qemu/int128.h | 4 ++-- 2 files changed, 12 insertions(+), 7 deletions(-)