Aarch64: Append explicit NILs to qualifier sequences
Explicitly assign the NIL qualifier to avoid relying on the numerical value of `AARCH64_OPND_QLF_NIL`.
This patch modifies the AArch64 opcode table to explicitly set the NIL qualifier for some opcodes where it was previously set implicitly. By avoiding implicit initialization, the code becomes independent of the numerical value of AARCH64_OPND_QLF_NIL. This improves code maintainability, as changes to the value of AARCH64_OPND_QLF_NIL will not unexpectedly affect these opcodes.
In Details
In the AArch64 backend, qualifier sequences in opcodes/aarch64-tbl.h define the qualifiers for each operand of an instruction. This patch appends explicit NIL qualifiers to sequences where they were previously implicit, ensuring that the correct qualifier is used regardless of the numerical value of AARCH64_OPND_QLF_NIL.
For Context
When an assembler translates instructions, it needs to know the specific details of each instruction's operands. Qualifiers provide these details. This patch makes the qualifiers more explicit, so the assembler doesn't have to rely on default values, which could change in the future and break things. This makes the assembler's code more reliable.