Re: [PATCH] target/ppc: avoid int32 multiply overflow in int_helper.c

[Richard Henderson]

On 6/2/22 07:14, Daniel Henrique Barboza wrote:
> Coverity is not thrilled about the multiply operations being done in
> ger_rank8() and ger_rank2(), giving an error like the following:
>
> Integer handling issues  (OVERFLOW_BEFORE_WIDEN)
>      Potentially overflowing expression "sextract32(a, 4 * i, 4) *
> sextract32(b, 4 * i, 4)" with type "int" (32 bits, signed) is evaluated
> using 32-bit arithmetic, and then used in a context that expects an
> expression of type "int64_t" (64 bits, signed).
>
> Fix both instances where this occur by adding an int64_t cast in the
> first operand, forcing the result to be 64 bit.
>
> Fixes: Coverity CID 1489444, 1489443
> Fixes: 345531533f26 ("target/ppc: Implemented xvi*ger* instructions")
> Cc: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
> Cc: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

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


r~