bart4...@gmail.com wrote:
(Although I think Python would have difficulty in turning x+=1 into a single opcode, if using normal object references and a shared object model.)
The ADD_ONE opcode would have to be defined to have the same effect as the sequence emitted for x+=1, including all the dynamic lookups, so the only speed advantage would be eliminating a few trips around the bytecode fetch-decode-execute loop. Which could still be worthwhile, if experience with the wordcode interpreter is anything to go by. There was also a project that attempted to find frequently used sequences of opcodes and create specialised opcodes for them, which reportedly had some success as well. The logic behind these approaches is that unpredictable branches, such as the opcode switch in the ceval loop, are expensive on modern architectures, so eliminating as many of them as possible can be a win. -- Greg -- https://mail.python.org/mailman/listinfo/python-list
