ARM AsmLexer

The attached patch implements simple target-specific AsmLexers for ARM and Thumb. They are shallow subclasses of a common tokenizer that uses a std::map of register names to IDs to recognize register names, and reports those as AsmToken::Register tokens instead of identifiers.
I intend to use the ARM and Thumb AsmLexers as part of an extension of the EnhancedDisassembly library, which provides tokenization and interpretation functions on top of the basic disassembler, to ARM.
Please let me know what you think of this patch.

Sean

arm-asm-lexer.diff (4.72 KB)