An experimental set of tools that generate instruction set simulators,assemblers, and disassemblers from a single description wasdeveloped to test if retargetable development tools would work forcommercial DSP processors and microprocessors. The processorinstruction set was described using a language called nML. TheTMS320C50 DSP processor and the ARM7 microprocessor weremodeled in nML. The resulting instruction set models executeabout 25,000 instructions per second, and compiled instruction setsimulation models execute about 150,000 instructions per second.The viability of this approach and the deficiencies of nML are discussed.

The problem of generalizing functional specifications for while loops is considered. This problem occurs frequently when trying to verify that an initialized loop satisfies some functional specification, i.e., produces outputs which are some function of the program inputs. The notion of a valid generalization of a loop specification is defined. A particularly simple valid generalization, a base generalization, is discussed. A property of many commonly occurring while loops, that of being uniformly implemented, is defined. A technique is presented which exploits this property in order to systematically achieve a valid generalization of the loop specification. Two classes of uniformly implemented loops that are particularly susceptible to this form of analysis are defined and discussed. The use of the proposed technique is illustrated with a number of applications. Finally, an implication of the concept of uniform loop implementation for the validation of the obtained generalization is explained.

The problem of analyzing an initialized loop and verifying that the program computes some particular function of its inputs is addressed. A heuristic technique for solving these problems is proposed that appears to work well in many commonly occurring cases. The use of the technique is illustrated with a number of applications. An attribute of initialized loops is identified that corresponds to the ``effort'' required to apply this method in a deterministic (i.e., guaranteed to succeed) manner. It is explained that in any case, the success of the proposed heuristic relies on the loop exhibiting a ``reasonable'' form of behavior.

Abstract Observations on the design of the special‐purpose scientific programming language SL/1 are presented. SL/1 is intended for applications programming of the Control Data Corporation Cyber 203, a very high‐performance vector processor, which is mainly used for scientific computation. The language design has been heavily influenced by the hardware characteristics of this machine and the needs of the Cyber 203 user community. Various aspects of the design of SL/1 are discussed and measurements of their use are presented. In addition, unexpected similarities between the resulting design of SL/1 and the design of FORTRAN are examined and several reasons for the continued widespread use of FORTRAN are suggested.