Publication in BibTeX Format

@TECHREPORT{AICPub641:1983,
  AUTHOR={Warren, David H. D.},
  TITLE={An Abstract Prolog Instruction Set},
  ADDRESS={333 Ravenswood Ave., Menlo Park, CA 94025},
  INSTITUTION={AI Center, SRI International},
  MONTH={Oct},
  NUMBER={309},
  YEAR={1983},
  KEYWORDS={Prolog},
  ABSTRACT={This report describes an abstract Prolog instruction set suitable for
     software, firmware, or hardware implementation. The instruction set is abstract
     in that certain details of its encoding and implementation are left open, so
     that it may be realized in a number of different forms. The forms that are
     contemplated are: 
 em Translation into a compact bytecode, with emulators
     written in C (for maximum portability), Progol (a macrolanguage generating
     machine code, for efficient software implementations as an alternative to direct
     compilation on machines such as the VAX), and VAX-730 microcode. em Compilation
     into the standard instructions of machines such as the VAX or DECsystem-10/20.
     em Hardware (or firmware) emulation of the instruction set on a specially designed
     Prolog processor. 
 The abstract machine described herein (``new Prolog
     Engine’’) is a major revision of the ``old Prolog Engine’’
     described in a previous document. The new model overcomes certain difficulties
     in the old model, which are discussed in a later section. The new model can
     be considered to be a modification of the old model, where the stack contains
     compiler-defined goals called environments instead of user-defined goals. The
     environments correspond to some number of goals forming the tail of a clause.
     The old model was developed having primarily in mind a VAX-730 microcode implementation.
     The new model has, in addition, been influenced by hardware implementation
     considerations, but should remain equally amenable to software or firmware
     implementation on machines such as the VAX.}
}