Re: [PATCH 01/20] target/arm: Fix return value from LDSMIN/LDSMAX 8/16 bit atomics

[Richard Henderson <richard.henderson@linaro.org>]

On 6/2/23 08:52, Peter Maydell wrote:
> The atomic memory operations are supposed to return the old memory
> data value in the destination register.  This value is not
> sign-extended, even if the operation is the signed minimum or
> maximum.  (In the pseudocode for the instructions the returned data
> value is passed to ZeroExtend() to create the value in the register.)
> 
> We got this wrong because we were doing a 32-to-64 zero extend on the
> result for 8 and 16 bit data values, rather than the correct amount
> of zero extension.
> 
> Fix the bug by using ext8u and ext16u for the MO_8 and MO_16 data
> sizes rather than ext32u.
> 
> Cc:qemu-stable@nongnu.org
> Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
> ---
>   target/arm/tcg/translate-a64.c | 18 ++++++++++++++++--
>   1 file changed, 16 insertions(+), 2 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~