Vectorised Logical Operations in Java 9

This is a short post for my own reference, since I feel I have already done the topic of does Java 9 use AVX for this? to death. Cutting to the chase, Java 9 autovectorises loops to compute logical ANDs, XORs, ORs and ANDNOTs between arrays, making use of the instructions VPXOR, VPOR and VPAND. […]

How much Algebra does C2 Know? Part 2: Distributivity

In part one of this series of posts, I looked at how important associativity and independence are for fast loops. C2 seems to utilise these properties to generate unrolled and pipelined machine code for loops, achieving higher throughput even in cases where the kernel of the loop is 3x slower according to vendor advertised instruction […]

Zeroing Negative Values in Arrays Efficiently

Replacing negatives with zeroes in large arrays of values is a primitive function of several complex financial risk measures, including potential future exposure (PFE) and the liquidity coverage ratio (LCR). While this is not an interesting operation by any stretch of the imagination, it is useful and there is significant benefit in its performance. This […]

Project Panama and Population Count

Project Panama introduces a new interface Vector, where the specialisation for long looks like a promising substrate for an explicitly vectorised bit set. Bit sets are useful for representing composable predicates over data sets. One obvious omission on this interface, required for an adequate implementation of a bit set, is a bit count, otherwise known […]