[intrinsics]: performance before after (String::format)

[Brian Goetz]

On 2/22/2019 4:46 PM, Alex Buckley wrote:
> Hi Vicente,
>
> Thanks for this nice testing. I am interested in the following results:
>
> 1. Variable strings
>
>                          Intrinsified  Vanilla  Speedup
> testStringFormat1VariableStr    10443     2394      44x
> testStringFormat2VariableStrs    9497       88     109x
> testStringFormat100VariableStrs   148        3      46x
>
> With no type conversions in the mix, any speedup comes from evaluating 
> the format string at compile time and emitting a series of string 
> concatenations for run time. 

A small bit probably also comes from eliminating the varargs boxing.