Re: [Qemu-devel] [PATCH v3] target-arm: fix neon shift helper functions

[Laurent Desnogues]

On Mon, Oct 26, 2009 at 8:01 AM,  <address@hidden> wrote:
> From: Juha Riihimäki <address@hidden>
>
> Current code is broken at least on recent compilers, comparison
> between signed and unsigned types yield incorrect code and render
> the neon shift helper functions defunct. This is the third revision
> of this patch, casting all comparisons with the sizeof operator to
> signed ssize_t type to force comparisons to be between signed integral
> types.
>
> Signed-off-by: Juha Riihimäki <address@hidden>

Acked-by: Laurent Desnogues <address@hidden>


Laurent

> ---
>  target-arm/neon_helper.c |   26 ++++++++++++++------------
>  1 files changed, 14 insertions(+), 12 deletions(-)
>
> diff --git a/target-arm/neon_helper.c b/target-arm/neon_helper.c
> index f32ecd6..5e6452b 100644
> --- a/target-arm/neon_helper.c
> +++ b/target-arm/neon_helper.c
> @@ -392,7 +392,8 @@ NEON_VOP(abd_u32, neon_u32, 1)
>  #define NEON_FN(dest, src1, src2) do { \
>     int8_t tmp; \
>     tmp = (int8_t)src2; \
> -    if (tmp >= sizeof(src1) * 8 || tmp <= -sizeof(src1) * 8) { \
> +    if (tmp >= (ssize_t)sizeof(src1) * 8 || \
> +        tmp <= -(ssize_t)sizeof(src1) * 8) { \
>         dest = 0; \
>     } else if (tmp < 0) { \
>         dest = src1 >> -tmp; \
> @@ -420,9 +421,9 @@ uint64_t HELPER(neon_shl_u64)(uint64_t val, uint64_t 
> shiftop)
>  #define NEON_FN(dest, src1, src2) do { \
>     int8_t tmp; \
>     tmp = (int8_t)src2; \
> -    if (tmp >= sizeof(src1) * 8) { \
> +    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
>         dest = 0; \
> -    } else if (tmp <= -sizeof(src1) * 8) { \
> +    } else if (tmp <= -(ssize_t)sizeof(src1) * 8) { \
>         dest = src1 >> (sizeof(src1) * 8 - 1); \
>     } else if (tmp < 0) { \
>         dest = src1 >> -tmp; \
> @@ -453,11 +454,11 @@ uint64_t HELPER(neon_shl_s64)(uint64_t valop, uint64_t 
> shiftop)
>  #define NEON_FN(dest, src1, src2) do { \
>     int8_t tmp; \
>     tmp = (int8_t)src2; \
> -    if (tmp >= sizeof(src1) * 8) { \
> +    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
>         dest = 0; \
> -    } else if (tmp < -sizeof(src1) * 8) { \
> +    } else if (tmp < -(ssize_t)sizeof(src1) * 8) { \
>         dest = src1 >> (sizeof(src1) * 8 - 1); \
> -    } else if (tmp == -sizeof(src1) * 8) { \
> +    } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \
>         dest = src1 >> (tmp - 1); \
>         dest++; \
>         dest >>= 1; \
> @@ -494,9 +495,10 @@ uint64_t HELPER(neon_rshl_s64)(uint64_t valop, uint64_t 
> shiftop)
>  #define NEON_FN(dest, src1, src2) do { \
>     int8_t tmp; \
>     tmp = (int8_t)src2; \
> -    if (tmp >= sizeof(src1) * 8 || tmp < -sizeof(src1) * 8) { \
> +    if (tmp >= (ssize_t)sizeof(src1) * 8 || \
> +        tmp < -(ssize_t)sizeof(src1) * 8) { \
>         dest = 0; \
> -    } else if (tmp == -sizeof(src1) * 8) { \
> +    } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \
>         dest = src1 >> (tmp - 1); \
>     } else if (tmp < 0) { \
>         dest = (src1 + (1 << (-1 - tmp))) >> -tmp; \
> @@ -528,14 +530,14 @@ uint64_t HELPER(neon_rshl_u64)(uint64_t val, uint64_t 
> shiftop)
>  #define NEON_FN(dest, src1, src2) do { \
>     int8_t tmp; \
>     tmp = (int8_t)src2; \
> -    if (tmp >= sizeof(src1) * 8) { \
> +    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
>         if (src1) { \
>             SET_QC(); \
>             dest = ~0; \
>         } else { \
>             dest = 0; \
>         } \
> -    } else if (tmp <= -sizeof(src1) * 8) { \
> +    } else if (tmp <= -(ssize_t)sizeof(src1) * 8) { \
>         dest = 0; \
>     } else if (tmp < 0) { \
>         dest = src1 >> -tmp; \
> @@ -579,11 +581,11 @@ uint64_t HELPER(neon_qshl_u64)(CPUState *env, uint64_t 
> val, uint64_t shiftop)
>  #define NEON_FN(dest, src1, src2) do { \
>     int8_t tmp; \
>     tmp = (int8_t)src2; \
> -    if (tmp >= sizeof(src1) * 8) { \
> +    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
>         if (src1) \
>             SET_QC(); \
>         dest = src1 >> 31; \
> -    } else if (tmp <= -sizeof(src1) * 8) { \
> +    } else if (tmp <= -(ssize_t)sizeof(src1) * 8) { \
>         dest = src1 >> 31; \
>     } else if (tmp < 0) { \
>         dest = src1 >> -tmp; \
> --
> 1.6.5
>
>
>
>