Matrix 4x4 multiplication (floats)

Matrix multiplication is done on a column x row basis. Given two input matrices m2, m3 we do the multiplication and store the result back to an output matrix m1. Hence the function prototype:

void Mat44MulTo(Mat44 m1, Mat44 m2, Mat44 m3);

Matrix 4x4 scaling (floats)

Scaling a matrix implies multiplying each element with a float. Assume the following prototype:

void Mat44ScaleTo(Mat44 m1, Mat44 m2, float f);

where we multiply matrix m2 with the float f and store the result into m1.

Matrix 4x4 addition/subtraction (floats)

Let's assume we want to do addition or substraction of 2 4x4 32-bit float matrices. First step is to load the arrays. We will assume that the arrays are 16-byte aligned (all/most SIMD engines require this) which will also give a nice boost. Let's assume we have the following typedef:

AltiVec vectorization of hashing algorithms

Hashing a piece of data is one of the most time consuming process in a a database. Basically, the process builds a unique integer (aka 'hash key') from a series of operations on the objects bytes. Usually these algorithms are not parallelizable, or at least not easily parallelizable, due to the dependency to previous calculations involved. Taking a single family of hashing algorithms, we will provide (with mathematical proof) a second deterministic way of calculating the Nth hash, using easily parallelizable tecniques and also provide the Altivec equivalent of this algorithm.


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