[AMDGPU][MC] Separate VOPC MnemonicAlias from Instruction (#89105)
Tablegen classes MnemonicAlias, Requires, and VOPC_Real, all define a
field 'Predicates'. The prior formulation resulted in the instantiated
record inheriting from all three to only have the Predicate set in
Requires, i.e. Gen.AssemblerPredicate. This breaks the design of
GCNPredicateControl (which is a parent class of VOPC_Real) that allows
multiple predicates such as SubtargetPredicate and OtherPredicates to be
set on an Instruction.
MnemonicAlias does not need to be defined in the same record as
VOPC_Real, so we can separate the definitions and remove Requires to
avoid the issue.
NFCI, but it enables future changes, such as setting multiple predicates
on a VOPC_Real.
llvm-project
44713f15 - [AMDGPU][MC] Separate VOPC MnemonicAlias from Instruction (#89105)
