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
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How much Algebra does C2 Know? Part 1: Associativity

Making loops execute faster is firmly rooted in algebra, but how much does C2 know or care about? When building a highly optimised query engine, a critical concern is the quality of assembly code generated for loops. There is a lot more to JIT compilation than loop optimisation; inlining, class hierarchy analysis, escape analysis to
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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
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