On Sat, Oct 24, 2009 at 2:19 PM, <juha.riihim...@nokia.com> wrote:
> From: Juha Riihimäki <juha.riihim...@nokia.com>
>
> Shift by immediate value is incorrectly overwritten by a temporary
> variable in the processing of NEON vsri, vshl and vsli instructions.
> This patch has been revised to also include a fix for the special
> case where the code would previously try to shift an integer value
> over 31 bits left/right.
>
> Signed-off-by: Juha Riihimäki <juha.riihim...@nokia.com>
Acked-by: Laurent Desnogues <laurent.desnog...@gmail.com>
Laurent
> ---
> target-arm/translate.c | 32 ++++++++++++++++++--------------
> 1 files changed, 18 insertions(+), 14 deletions(-)
>
> diff --git a/target-arm/translate.c b/target-arm/translate.c
> index d1e2ed2..9e924d4 100644
> --- a/target-arm/translate.c
> +++ b/target-arm/translate.c
> @@ -4098,7 +4098,7 @@ static int disas_neon_data_insn(CPUState * env,
> DisasContext *s, uint32_t insn)
> int pairwise;
> int u;
> int n;
> - uint32_t imm;
> + uint32_t imm, mask;
> TCGv tmp, tmp2, tmp3, tmp4, tmp5;
> TCGv_i64 tmp64;
>
> @@ -4626,31 +4626,35 @@ static int disas_neon_data_insn(CPUState * env,
> DisasContext *s, uint32_t insn)
> switch (size) {
> case 0:
> if (op == 4)
> - imm = 0xff >> -shift;
> + mask = 0xff >> -shift;
> else
> - imm = (uint8_t)(0xff << shift);
> - imm |= imm << 8;
> - imm |= imm << 16;
> + mask = (uint8_t)(0xff << shift);
> + mask |= mask << 8;
> + mask |= mask << 16;
> break;
> case 1:
> if (op == 4)
> - imm = 0xffff >> -shift;
> + mask = 0xffff >> -shift;
> else
> - imm = (uint16_t)(0xffff << shift);
> - imm |= imm << 16;
> + mask = (uint16_t)(0xffff << shift);
> + mask |= mask << 16;
> break;
> case 2:
> - if (op == 4)
> - imm = 0xffffffffu >> -shift;
> - else
> - imm = 0xffffffffu << shift;
> + if (shift < -31 || shift > 31) {
> + mask = 0;
> + } else {
> + if (op == 4)
> + mask = 0xffffffffu >> -shift;
> + else
> + mask = 0xffffffffu << shift;
> + }
> break;
> default:
> abort();
> }
> tmp2 = neon_load_reg(rd, pass);
> - tcg_gen_andi_i32(tmp, tmp, imm);
> - tcg_gen_andi_i32(tmp2, tmp2, ~imm);
> + tcg_gen_andi_i32(tmp, tmp, mask);
> + tcg_gen_andi_i32(tmp2, tmp2, ~mask);
> tcg_gen_or_i32(tmp, tmp, tmp2);
> dead_tmp(tmp2);
> }
> --
> 1.6.5
>
>
>
>
