No I don't mean asm.js. You can write vanilla JS that avoids memory allocation beyond initialization as well as garbage collection, and runs certain algorithms

No I don't mean asm.js. You can write vanilla JS that avoids memory allocation beyond initialization as well as garbage collection, and runs certain algorithms faster than typical C due to differences such as JIT optimizations or the lack of a sentinel to terminate strings, etc. My point was never to say that JS is in general as fast as C, only that a careful dev that is familiar with the VM's operation can get close for some tasks.