[Python-Dev] Bytecode idea

[Christian Tismer]

Raymond Hettinger wrote:
> This is true. I used this in my optimization from two
> years ago, and moved the oparg preparation into the
> opcode cases, not doing any test, but just fetching
> the argument.
> 
> 
> What happened to the optimization.  It is not in the
> current code?

No. At that time, ceval speedups were not
popular, so I used the optimization just
to make Stackless appear faster than CPython,
although CPython would have been *even more*
faster.

>>I also turned this into macros which
>>added to the insn pointer only once.
>>Incredible but true: Most of the win I gathered was
>>by typecasting the oparg access differently into
>>a reference to a short int, instead of oring two
>>bytes. 
> 
> 
> I skipped over that one because I thought that 
> it would fail on a big-endian computer.

Sure it would fail. But on little endian like
X86, it produced much faster code, so I only
defined it for certain platforms.

ciao - chris
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