Copyright (c) 1979 The Regents of the University of California.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the University of
California, Berkeley and its contributors.
4. Neither the name of the University nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
@(#)pxin0.n 5.2 (Berkeley) 4/17/91
.RP Berkeley Pascal PX Implementation Notes
Version 2.0 - January, 1979 .AU William N. Joy\*(Dg .AU M. Kirk McKusick\*(Dd .AI Computer Science Division Department of Electrical Engineering and Computer Science University of California, Berkeley Berkeley, California 94720 .AB
Berkeley Pascal is designed for interactive instructional use and runs on the "VAX 11/780" . The interpreter px executes the Pascal binaries generated by the Pascal translator pi .
The PX Implementation Notes .R describe the general organization of px , detail the various operations of the interpreter, and describe the file input/output structure. Conclusions are given on the viability of an interpreter based approach to language implementation for an instructional environment. .AE
IntroductionThese PX Implementation Notes .R have been updated from the original "PDP 11/70" implementation notes to reflect the interpreter that runs on the "VAX 11/780" . These notes consist of four major parts. The first part outlines the general organization of px . Section 2 describes the operations (instructions) of the interpreter while section 3 focuses on input/output related activity. A final section gives conclusions about the viability of an interpreter based approach to language implementation for instruction.
Related Berkeley Pascal documentsThe "PXP Implementation Notes" give details of the internals of the execution profiler pxp; parts of the interpreter related to pxp are discussed in section 2.10. A paper describing the syntactic error recovery mechanism used in pi was presented at the ACM Conference on Compiler Construction in Boulder Colorado in August, 1979.
AcknowledgementsThis version of px is a "PDP 11/70" to "VAX 11/780" opcode mapping of the original px that was designed and implemented by Ken Thompson, with extensive modifications and additions by William Joy and Charles Haley. Without their work, this P system would never have existed. These notes were first written by William Joy for the "PDP 11/70" implementation. We would also like to thank our faculty advisor Susan L. Graham for her encouragement, her helpful comments and suggestions relating to P and her excellent editorial assistance. .FS \*(dg The financial support of the National Science Foundation under grants MCS74-07644-A03 and MCS78-07291 and of an \s-2IBM\s0 Graduate Fellowship are gratefully acknowledged. .FE .FS \*(dd The financial support of a Howard Hughes Graduate Fellowship is gratefully acknowledged. .FE .bp