There are three set operators defined in XQuery, namely union, intersect and except. They take node sequences as operands, in which each node is identified by its node-ID and treated as an atomic entity. However, according to XML semantics, each node is “a set of set(s)”, which have descendants in a tree-structured hierarchy. Unfortunately, the regular set operators as described above ignored t...

The Neural GPU is a recent model that can learn algorithms such as multi-digit binary addition and binary multiplication in a way that generalizes to inputs of arbitrary length. We show that there are two simple ways of improving the performance of the Neural GPU: by carefully designing a curriculum, and by increasing model size. The latter requires a memory efficient implementation, as a naive...

In general, the FPU and processor are decoupled in the method for FPU integration, in which the communication between them requires software intervention and ultra-precision FPU is unsupported. To avoid this problem, a method based on fine-grained control for integration of FPU into the RISC processor is proposed in this paper. In terms of operand width of floating-point instructions, the metho...

Programs represented in Static Single Assignment (SSA) form contain phi instructions (or functions) whose operational semantics are to merge values coming from distinct control flow paths. However, translating phi instructions into native instructions is nontrivial when transformations such as copy propagation and code motion have been performed. In this paper we present a new framework for tra...

Cognitive arithmetic studies the mental processes used in solving math problems. This area of research explores the retrieval mechanisms and strategies used by people during a common cognitive task. Past research has shown that human performance in arithmetic operations is correlated to the numerical size of the problem. Past research on cognitive arithmetic has pinpointed this trend to either ...

We show that RSA implementation present in OpenSSL can be successfully attacked using sidechannels. In OpenSSL, the modular exponentiation is implemented using m-ary method, where a table of size 2m entries is precomputed. The exponent is divided into words of m-bits each and the algorithm proceeds one word at a time using the precomputed table. Furthermore, to protect against side-channel atta...

z990 floatingpoint unit G. Gerwig H. Wetter E. M. Schwarz J. Haess C. A. Krygowski B. M. Fleischer M. Kroener The floating-point unit (FPU) of the IBM z990 eServer is the first one in an IBM mainframe with a fused multiply-add dataflow. It also represents the first time that an SRT divide algorithm (named after Sweeney, Robertson, and Tocher, who independently proposed the algorithm) was used i...

An object algebra is presented as a formal query model for object-oriented databases. The algebra serves not only to access and manipulate the structure and behavior of objects, but also supports the creation of new objects and the introduction of new relationships into the schema. It provides a more powerful and flexible tool than do messages for effectively dealing with complex situations and...

In this paper we investigate the Sum Absolute Difference (SAD) operation, an operation frequently used by a number of algorithms for digital motion estimation. For such operation, we propose a single vector instruction that can be performed (in hardware) on an entire block of data in parallel. We investigate possible implementations for such an instruction. Assuming a machine cycle comparable t...

In general-purpose microprocessors, recent trends have pushed towards 64-bit word widths, primarily to accommodate the large addressing needs of some programs. Many integer problems, however, rarely need the full 64-bit dynamic range these CPUs provide. In fact, another recent instruction set trend has been increased support for sub-word operations (that is, manipulating data in quantities less...