Coverity found a second DEADCODE issue in rmw_xireg() claiming that we can't
reach 'RISCV_EXCP_NONE' at the 'done' label:
> 2706 done:
> 2707 if (ret) {
> 2708 return (env->virt_enabled && virt) ?
> 2709 RISCV_EXCP_VIRT_INSTRUCTION_FAULT : RISCV_EXCP_ILLEGAL_INST;
> 2710 }
>>>> CID 1590356: Control flow issues (DEADCODE)
>>>> Execution cannot reach this statement: "return RISCV_EXCP_NONE;".
> 2711 return RISCV_EXCP_NONE;
Our label is now reduced after fixing another deadcode in the previous
patch but the problem reported here still remains:
done:
if (ret) {
return RISCV_EXCP_ILLEGAL_INST;
}
return RISCV_EXCP_NONE;
This happens because 'ret' changes only once at the start of the
function:
ret = smstateen_acc_ok(env, 0, SMSTATEEN0_SVSLCT);
if (ret != RISCV_EXCP_NONE) {
return ret;
}
So it's a guarantee that ret will be RISCV_EXCP_NONE (-1) if we ever
reach the label, i.e. "if (ret)" will always be true, and the label can
be even further reduced to:
done:
return RISCV_EXCP_ILLEGAL_INST;
To make a better use of the label, remove the 'else' from the
xiselect_aia_range() chain and let it fall-through to the 'done' label
since they are now both returning RISCV_EXCP_ILLEGAL_INST.
Resolves: Coverity CID 1590356
Fixes: dc0280723d ("target/riscv: Decouple AIA processing from xiselect and xireg")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20250121184847.2109128-3-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
e07a89143b