* Add encodings for i8 and i16 copy, spill, fill, ireduce.i8.i16
Also adds legalization for srem, irsub_imm, {u,s}extend.i16.i8
Fixes#477 cc #466
* Legalize popcnt, clz and ctz for i8 and i16
* Fix bug in call_memset
* Add 'jump_table_entry' and 'indirect_jump' instructions.
* Update CodeSink to keep track of code size. Pretty up clif-util's disassembly output.
* Only disassemble the machine portion of output. Pretty print the read-only data after it.
* Update switch frontend code to use new br_table instruction w/ default.
* Reorganize the global value kinds.
This:
- renames "deref" global values to "load" and gives it a offset that works
like the "load" instructions' does
- adds an explicit "iadd_imm" global value kind, which replaces the
builtin iadd in "vmctx" and "deref" global values.
- also renames "globalsym" to "symbol"
