[Vm-dev] VMBIGENDIAN question (was: A proposal to split VMMaker into subpackages)

[Bert Freudenberg]

On 2013-03-22, at 05:43, David T. Lewis <lewis at mail.msen.com> wrote:

> "It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so."
> -- Mark Twain
> 
> An interpreter VM compiled with the normal C macros in sqMemoryAccess.h (for "performance"):
> 
> 0 tinyBenchmarks. '417277913 bytecodes/sec; 14395420 sends/sec'
> 0 tinyBenchmarks. '414239482 bytecodes/sec; 14646769 sends/sec'
> 0 tinyBenchmarks. '417277913 bytecodes/sec; 14406658 sends/sec'
> 
> The same interpreter VM with C macros replaced by Smalltalk slang (class MemoryAccess):
> 
> 0 tinyBenchmarks. '455111111 bytecodes/sec; 14217973 sends/sec'
> 0 tinyBenchmarks. '451897616 bytecodes/sec; 14485815 sends/sec'
> 0 tinyBenchmarks. '453900709 bytecodes/sec; 14497194 sends/sec'
> 
> Dave

That is ... unexpected :)

But it again shows the importance of the 3rd rule of Optimization.
http://c2.com/cgi/wiki?RulesOfOptimization

- Bert -