share/doc/papers/px/pxin0.n

   1 .\"     $NetBSD: pxin0.n,v 1.2 1998/01/09 06:41:54 perry Exp $
   2 .\"
   3 .\" Copyright (c) 1979 The Regents of the University of California.
   4 .\" All rights reserved.
   5 .\"
   6 .\" Redistribution and use in source and binary forms, with or without
   7 .\" modification, are permitted provided that the following conditions
   8 .\" are met:
   9 .\" 1. Redistributions of source code must retain the above copyright
  10 .\"    notice, this list of conditions and the following disclaimer.
  11 .\" 2. Redistributions in binary form must reproduce the above copyright
  12 .\"    notice, this list of conditions and the following disclaimer in the
  13 .\"    documentation and/or other materials provided with the distribution.
  14 .\" 3. Neither the name of the University nor the names of its contributors
  15 .\"    may be used to endorse or promote products derived from this software
  16 .\"    without specific prior written permission.
  17 .\"
  18 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21 .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28 .\" SUCH DAMAGE.
  29 .\"
  30 .\"     @(#)pxin0.n     5.2 (Berkeley) 4/17/91
  31 .\"
  32 .if !\n(xx .so tmac.p
  33 .RP
  34 .TL
  35 Berkeley Pascal
  36 PX Implementation Notes
  37 .br
  38 Version 2.0 \- January, 1979
  39 .AU
  40 William N. Joy\*(Dg
  41 .AU
  42 M. Kirk McKusick\*(Dd
  43 .AI
  44 Computer Science Division
  45 Department of Electrical Engineering and Computer Science
  46 University of California, Berkeley
  47 Berkeley, California  94720
  48 .AB
  49 .PP
  50 Berkeley Pascal
  51 is designed for interactive instructional use and runs on the
  52 .SM "VAX 11/780" .
  53 The interpreter
  54 .I px
  55 executes the Pascal binaries generated by the Pascal translator
  56 .I pi .
  57 .PP
  58 The
  59 .I
  60 PX Implementation Notes
  61 .R
  62 describe the general organization of
  63 .I px ,
  64 detail the various operations of the interpreter,
  65 and describe the file input/output structure.
  66 Conclusions are given on the viability of an interpreter
  67 based approach to language implementation for an instructional environment.
  68 .AE
  69 .if n 'ND
  70 .SH
  71 Introduction
  72 .PP
  73 These
  74 .I
  75 PX Implementation Notes
  76 .R
  77 have been updated from the  original
  78 .SM "PDP 11/70"
  79 implementation notes to reflect the interpreter that runs on the
  80 .SM "VAX 11/780" .
  81 These notes consist of four major parts.
  82 The first part outlines the general organization of
  83 .I px .
  84 Section 2 describes the operations (instructions) of the interpreter
  85 while section 3 focuses on input/output related activity.
  86 A final section gives conclusions about the viability of an interpreter
  87 based approach to language implementation for instruction.
  88 .SH
  89 Related Berkeley Pascal documents
  90 .PP
  91 The
  92 .I "PXP Implementation Notes"
  93 give details of the internals of the execution profiler
  94 .I pxp;
  95 parts of the interpreter related to
  96 .I pxp
  97 are discussed in section 2.10.
  98 A paper describing the syntactic error recovery mechanism used in
  99 .I pi
 100 was presented at the ACM Conference on Compiler Construction
 101 in Boulder Colorado in August, 1979.
 102 .SH
 103 Acknowledgements
 104 .PP
 105 This version of
 106 .I px
 107 is a
 108 .SM "PDP 11/70"
 109 to
 110 .SM "VAX 11/780"
 111 opcode mapping of the original
 112 .I px
 113 that was designed and implemented by Ken Thompson,
 114 with extensive modifications and additions
 115 by William Joy
 116 and Charles Haley.
 117 Without their work, this
 118 .UP
 119 system would never have existed.
 120 These notes were first written by William Joy for the
 121 .SM "PDP 11/70"
 122 implementation.
 123 We would also like to thank our faculty advisor Susan L. Graham
 124 for her encouragement,
 125 her helpful comments and suggestions
 126 relating to
 127 .UP
 128 and her excellent editorial assistance.
 129 .FS
 130 \*(dg\ The financial support of the National Science Foundation under grants
 131 MCS74-07644-A03 and MCS78-07291
 132 and of an \s-2IBM\s0 Graduate Fellowship are gratefully acknowledged.
 133 .FE
 134 .FS
 135 \*(dd\ The financial support of a Howard Hughes Graduate
 136 Fellowship is gratefully acknowledged.
 137 .FE
 138 .bp