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