Cache-friendlier than past versions happens all the time for PHP and Javascript. A fair amount of the gains in PHP7 were optimizations that reduced reallocatio

Cache-friendlier than past versions happens all the time for PHP and Javascript. A fair amount of the gains in PHP7 were optimizations that reduced reallocation of memory, "packed arrays" where if an array is all ints to store it in a more compact structure, etc. Polymorphic inline caching would be another example of trying to reduce the performance impact of a dynamically typed language...being more cache friendly despite the handicap of not knowing everything until runtime.