Re: [Qemu-ppc] [Qemu-devel] [PATCH 2/7] target-ppc: Implement unsigned quadword left/right shift and unit tests

[Richard Henderson]

On 12/02/2016 09:00 PM, Jose Ricardo Ziviani wrote:
> +++ b/include/qemu/host-utils.h
> @@ -29,6 +29,33 @@
>  #include "qemu/bswap.h"
>
>  #ifdef CONFIG_INT128
> +static inline void urshift(uint64_t *plow, uint64_t *phigh, uint32_t shift)
> +{
> +    __uint128_t val = ((__uint128_t)*phigh << 64) | *plow;
> +    val >>= (shift & 127);
> +    *phigh = val >> 64;
> +    *plow = val & 0xffffffffffffffff;
> +}
> +
> +static inline void ulshift(uint64_t *plow, uint64_t *phigh,
> +                           uint32_t shift, bool *overflow)
> +{
> +    __uint128_t val = ((__uint128_t)*phigh << 64) | *plow;
> +
> +    if (shift == 0) {
> +        return;
> +    }
> +
> +    if (shift > 127 || (val >> (128 - (shift & 127))) != 0) {
> +        *overflow = true;
> +    }
> +
> +    val <<= (shift & 127);
> +
> +    *phigh = val >> 64;
> +    *plow = val & 0xffffffffffffffff;
> +}
> +

This belongs in qemu/int128.h, not here.  And certainly not predicated on 
CONFIG_INT128.


r~