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| author | Richard Henderson <richard.henderson@linaro.org> | 2022-10-17 09:17:20 +1000 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2023-02-04 06:19:42 -1000 |
| commit | b959822c94e6d32b36fad038e79c14f841e585c1 (patch) | |
| tree | b2c201a190f542726172ee62d6b4738dd14b0568 /include/qemu/int128.h | |
| parent | c6556aa0c8de8718813fea0ca61232632bf33c42 (diff) | |
| download | focaccia-qemu-b959822c94e6d32b36fad038e79c14f841e585c1.tar.gz focaccia-qemu-b959822c94e6d32b36fad038e79c14f841e585c1.zip | |
include/qemu/int128: Use Int128 structure for TCI
We are about to allow passing Int128 to/from tcg helper functions, but libffi doesn't support __int128_t, so use the structure. In order for atomic128.h to continue working, we must provide a mechanism to frob between real __int128_t and the structure. Provide a new union, Int128Alias, for this. We cannot modify Int128 itself, as any changed alignment would also break libffi. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'include/qemu/int128.h')
| -rw-r--r-- | include/qemu/int128.h | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/include/qemu/int128.h b/include/qemu/int128.h index d2b76ca6ac..f62a46b48c 100644 --- a/include/qemu/int128.h +++ b/include/qemu/int128.h @@ -3,7 +3,12 @@ #include "qemu/bswap.h" -#ifdef CONFIG_INT128 +/* + * With TCI, we need to use libffi for interfacing with TCG helpers. + * But libffi does not support __int128_t, and therefore cannot pass + * or return values of this type, force use of the Int128 struct. + */ +#if defined(CONFIG_INT128) && !defined(CONFIG_TCG_INTERPRETER) typedef __int128_t Int128; static inline Int128 int128_make64(uint64_t a) @@ -460,8 +465,7 @@ Int128 int128_divu(Int128, Int128); Int128 int128_remu(Int128, Int128); Int128 int128_divs(Int128, Int128); Int128 int128_rems(Int128, Int128); - -#endif /* CONFIG_INT128 */ +#endif /* CONFIG_INT128 && !CONFIG_TCG_INTERPRETER */ static inline void bswap128s(Int128 *s) { @@ -472,4 +476,19 @@ static inline void bswap128s(Int128 *s) #define INT128_MAX int128_make128(UINT64_MAX, INT64_MAX) #define INT128_MIN int128_make128(0, INT64_MIN) +/* + * When compiler supports a 128-bit type, define a combination of + * a possible structure and the native types. Ease parameter passing + * via use of the transparent union extension. + */ +#ifdef CONFIG_INT128 +typedef union { + Int128 s; + __int128_t i; + __uint128_t u; +} Int128Alias __attribute__((transparent_union)); +#else +typedef Int128 Int128Alias; +#endif /* CONFIG_INT128 */ + #endif /* INT128_H */ |