If __int128 is not supported, prefer a base type that is returned in registers rather than memory.
Signed-off-by: Richard Henderson <r...@twiddle.net> --- include/qemu/int128.h | 110 +++++++++++++++++++++++++++++++------------------- 1 file changed, 69 insertions(+), 41 deletions(-) diff --git a/include/qemu/int128.h b/include/qemu/int128.h index 67440fa..ab67275 100644 --- a/include/qemu/int128.h +++ b/include/qemu/int128.h @@ -139,27 +139,37 @@ static inline void int128_subfrom(Int128 *a, Int128 b) #else /* !CONFIG_INT128 */ -typedef struct Int128 Int128; +/* Here we are catering to the ABI of the host. If the host returns + 64-bit complex in registers, but the 128-bit structure in memory, + then choose the complex representation. */ +#if defined(__GNUC__) \ + && (defined(__powerpc__) || defined(__sparc__)) \ + && !defined(CONFIG_TCG_INTERPRETER) +typedef _Complex unsigned long long Int128; -struct Int128 { - uint64_t lo; - int64_t hi; -}; +static inline Int128 int128_make128(uint64_t lo, uint64_t hi) +{ + return lo + 1i * hi; +} -static inline Int128 int128_make64(uint64_t a) +static inline uint64_t int128_getlo(Int128 a) { - return (Int128) { a, 0 }; + return __real__ a; } -static inline Int128 int128_make128(uint64_t lo, uint64_t hi) +static inline int64_t int128_gethi(Int128 a) { - return (Int128) { lo, hi }; + return __imag__ a; } +#else +typedef struct Int128 { + uint64_t lo; + int64_t hi; +} Int128; -static inline uint64_t int128_get64(Int128 a) +static inline Int128 int128_make128(uint64_t lo, uint64_t hi) { - assert(!a.hi); - return a.lo; + return (Int128) { lo, hi }; } static inline uint64_t int128_getlo(Int128 a) @@ -171,78 +181,92 @@ static inline int64_t int128_gethi(Int128 a) { return a.hi; } +#endif /* complex 128 */ + +static inline Int128 int128_make64(uint64_t a) +{ + return int128_make128(a, 0); +} + +static inline uint64_t int128_get64(Int128 a) +{ + assert(int128_gethi(a) == 0); + return int128_getlo(a); +} static inline Int128 int128_zero(void) { - return int128_make64(0); + return int128_make128(0, 0); } static inline Int128 int128_one(void) { - return int128_make64(1); + return int128_make128(1, 0); } static inline Int128 int128_2_64(void) { - return (Int128) { 0, 1 }; + return int128_make128(0, 1); } static inline Int128 int128_exts64(int64_t a) { - return (Int128) { .lo = a, .hi = (a < 0) ? -1 : 0 }; + return int128_make128(a, a < 0 ? -1 : 0); } static inline Int128 int128_and(Int128 a, Int128 b) { - return (Int128) { a.lo & b.lo, a.hi & b.hi }; + uint64_t al = int128_getlo(a), bl = int128_getlo(b); + uint64_t ah = int128_gethi(a), bh = int128_gethi(b); + + return int128_make128(al & bl, ah & bh); } static inline Int128 int128_rshift(Int128 a, int n) { - int64_t h; - if (!n) { - return a; - } - h = a.hi >> (n & 63); - if (n >= 64) { + uint64_t al = int128_getlo(a), ah = int128_gethi(a); + int64_t h = ((int64_t)ah) >> (n & 63); + if (n & 64) { return int128_make128(h, h >> 63); } else { - return int128_make128((a.lo >> n) | ((uint64_t)a.hi << (64 - n)), h); + return int128_make128((al >> n) | (ah << (64 - n)), h); } } static inline Int128 int128_add(Int128 a, Int128 b) { - uint64_t lo = a.lo + b.lo; + uint64_t al = int128_getlo(a), bl = int128_getlo(b); + uint64_t ah = int128_gethi(a), bh = int128_gethi(b); + uint64_t lo = al + bl; - /* a.lo <= a.lo + b.lo < a.lo + k (k is the base, 2^64). Hence, - * a.lo + b.lo >= k implies 0 <= lo = a.lo + b.lo - k < a.lo. - * Similarly, a.lo + b.lo < k implies a.lo <= lo = a.lo + b.lo < k. - * - * So the carry is lo < a.lo. - */ - return int128_make128(lo, (uint64_t)a.hi + b.hi + (lo < a.lo)); + return int128_make128(lo, ah + bh + (lo < al)); } -static inline Int128 int128_neg(Int128 a) +static inline Int128 int128_sub(Int128 a, Int128 b) { - uint64_t lo = -a.lo; - return int128_make128(lo, ~(uint64_t)a.hi + !lo); + uint64_t al = int128_getlo(a), bl = int128_getlo(b); + uint64_t ah = int128_gethi(a), bh = int128_gethi(b); + + return int128_make128(al - bl, ah - bh - (al < bl)); } -static inline Int128 int128_sub(Int128 a, Int128 b) +static inline Int128 int128_neg(Int128 a) { - return int128_make128(a.lo - b.lo, (uint64_t)a.hi - b.hi - (a.lo < b.lo)); + uint64_t al = int128_getlo(a), ah = int128_gethi(a); + return int128_make128(-al, ~ah + !al); } static inline bool int128_nonneg(Int128 a) { - return a.hi >= 0; + return int128_gethi(a) >= 0; } static inline bool int128_eq(Int128 a, Int128 b) { - return a.lo == b.lo && a.hi == b.hi; + uint64_t al = int128_getlo(a), bl = int128_getlo(b); + uint64_t ah = int128_gethi(a), bh = int128_gethi(b); + + return al == bl && ah == bh; } static inline bool int128_ne(Int128 a, Int128 b) @@ -252,7 +276,10 @@ static inline bool int128_ne(Int128 a, Int128 b) static inline bool int128_ge(Int128 a, Int128 b) { - return a.hi > b.hi || (a.hi == b.hi && a.lo >= b.lo); + uint64_t al = int128_getlo(a), bl = int128_getlo(b); + int64_t ah = int128_gethi(a), bh = int128_gethi(b); + + return ah > bh || (ah == bh && al >= bl); } static inline bool int128_lt(Int128 a, Int128 b) @@ -272,7 +299,8 @@ static inline bool int128_gt(Int128 a, Int128 b) static inline bool int128_nz(Int128 a) { - return a.lo || a.hi; + uint64_t al = int128_getlo(a), ah = int128_gethi(a); + return (al | ah) != 0; } static inline Int128 int128_min(Int128 a, Int128 b) -- 2.5.5