Aarch64: Return QLF_ERR for error conditions
Modify `vectype_to_qualifier` and `get_qualifier_from_partial_encoding` to return `AARCH64_OPND_QLF_ERR` instead of `AARCH64_OPND_QLF_NIL` on errors.
This patch changes the functions vectype_to_qualifier and get_qualifier_from_partial_encoding to return AARCH64_OPND_QLF_ERR instead of AARCH64_OPND_QLF_NIL when an error condition is encountered. This makes error handling more explicit and consistent within the AArch64 assembly code, which helps catch errors earlier and could simplify debugging.
In Details
In the AArch64 backend, vectype_to_qualifier and get_qualifier_from_partial_encoding are responsible for determining the operand qualifier based on vector type information or partial encoding. Returning AARCH64_OPND_QLF_ERR instead of AARCH64_OPND_QLF_NIL provides a clearer indication of error conditions during operand processing in gas/config/tc-aarch64.c.
For Context
When the assembler encounters an instruction, it needs to determine the specific type of data the instruction will operate on. Operand qualifiers provide this information. This patch modifies functions that determine these qualifiers to return a specific ERR code when something goes wrong, rather than a generic NIL value. This makes it easier to identify and handle errors during the assembly process.