[Python-Dev] Improving the bytecode

[Serhiy Storchaka]

Following the converting 8-bit bytecode to 16-bit bytecode (wordcode), 
there are other issues for improving the bytecode.

1. http://bugs.python.org/issue27129
Make the bytecode more 16-bit oriented.

2. http://bugs.python.org/issue27140
Add new opcode BUILD_CONST_KEY_MAP for building a dict with constant 
keys. This optimize the common case and especially helpful for two 
following issues (creating and calling functions).

3. http://bugs.python.org/issue27095
Simplify MAKE_FUNCTION/MAKE_CLOSURE. Instead packing three numbers in 
oparg the new MAKE_FUNCTION takes built tuples and dicts from the stack. 
MAKE_FUNCTION and MAKE_CLOSURE are merged in the single opcode.

4. http://bugs.python.org/issue27213
Rework CALL_FUNCTION* opcodes. Replace four existing opcodes with three 
simpler and more efficient opcodes.

5. http://bugs.python.org/issue27127
Rework the for loop implementation.

6. http://bugs.python.org/issue17611
Move unwinding of stack for "pseudo exceptions" from interpreter to 
compiler.