Manage Inits in a FoldingSet. This provides several benefits:
- Memory for Inits is properly managed
- Duplicate Inits are folded into Flyweights, saving memory
- It enforces const-correctness, protecting against certain classes
of bugs
The above benefits allow Inits to be used in more contexts, which in
turn provides more dynamism to TableGen. This enhanced capability
will be used by the AVX code generator to a fold common patterns
together.
llvm-svn: 134907
For now this is distinct from isCodeGenOnly, as code-gen-only
instructions can (and often do) still have encoding information
associated with them. Once we've migrated all of them over to true
pseudo-instructions that are lowered to real instructions prior to
the printer/emitter, we can remove isCodeGenOnly and just use isPseudo.
llvm-svn: 134539
A major part of its (eventual) goal is to support a much cleaner separation between disassembly callbacks
provided by the target and the disassembler emitter itself, i.e. not requiring hardcoding of knowledge in tblgen
like the existing disassembly emitters do.
The hope is that some day this will allow us to replace the existing non-Thumb ARM disassembler and remove
some of the hacks the old one introduced to tblgen.
llvm-svn: 125966