On 7/31/24 20:07, Ilya Leoshkevich wrote:
divdu (without a dot) sometimes updates cr0, even though it shouldn't. The reason is that gen_op_arith_divd() checks Rc(ctx->opcode), which is not initialized. This field is initialized only for instructions that go through decode_legacy(), and not decodetree.There already was a similar issue fixed in commit 86e6202a57b1 ("target/ppc: Make divw[u] handler method decodetree compatible."). It's not immediately clear what else may access the uninitialized ctx->opcode, so instead of playing whack-a-mole and changing the check to compute_rc0, simply initialize ctx->opcode. Cc: [email protected] Fixes: 99082815f17f ("target/ppc: Add infrastructure for prefixed insns") Signed-off-by: Ilya Leoshkevich <[email protected]>
Accessing opcode from decodetree should not happen -- divd needs fixing. But I agree this is a good short-term workaround for the release, so: Reviewed-by: Richard Henderson <[email protected]> r~
