[Python-Dev] Bytecode analysis

[Skip Montanaro]

    Damien> Ive done a static analysis of the bytecodes from compiling the
    Damien> python standard library:

    ...

Nice input, but I think you should deal with dynamic opcode frequencies.
See the #define's in the ceval.c source for how to enable that and the
recent thread in c.l.py.  In short, it doesn't really matter how many
LOAD_CONST instructions appear in the bytecode stream, only how many of them
are executed.  While LOAD_CONST is a relatively frequently executed opcode,
if I recall correctly, LOAD_FAST is much more frequently executed, and
LOAD_CONST is already pretty fast, so adding special opcodes probably won't
buy you much and runs the risk of disturbing what locality of reference
exists.

The LOAD_IF_FALSE issue was discussed recently (here I think).  The problem
is that chained operations like

    if a < b < c:
        ...

require the value be retained.  You could get rid of the separate POP_TOP
instruction but it would require some work in the compiler.

as-always-patches-are-welcome-ly, y'rs,

Skip