diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2023-05-24 08:14:41 -0700 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2023-05-30 09:51:11 -0700 |
| commit | 6479dd74f14d51f207509aa1b77b039b7bd32bff (patch) | |
| tree | b2dc0c1ad09c6f5f0488ec031b301a678fbdeef9 | |
| parent | 9e0e6a7e8e2351ca757f08f491ef99bbc2afd548 (diff) | |
meson: Split test for __int128_t type from __int128_t arithmetic
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 it can be used 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.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
| -rw-r--r-- | include/qemu/int128.h | 4 | ||||
| -rw-r--r-- | meson.build | 15 |
2 files changed, 12 insertions, 7 deletions
diff --git a/include/qemu/int128.h b/include/qemu/int128.h index 9e46cfaefc..73624e8be7 100644 --- a/include/qemu/int128.h +++ b/include/qemu/int128.h @@ -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 */ diff --git a/meson.build b/meson.build index 2d48aa1e2e..bc76ea96bf 100644 --- a/meson.build +++ b/meson.build @@ -2543,7 +2543,13 @@ 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) { @@ -2552,10 +2558,9 @@ 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. @@ -2564,7 +2569,7 @@ 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); @@ -2586,7 +2591,7 @@ 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; } |