1*2078SmckusickCopyright (c) 1979 Regents of the University of California 2*2078Smckusick 3*2078Smckusicksccsid = "@(#)READ_ME 1.1 01/07/81" 4*2078Smckusick 5*2078Smckusick This directory contains the source code for the Version 7 VAX 6*2078Smckusickinterpreter for Pascal. Following standard convensions, the makefile 7*2078Smckusickcontains four commands: 8*2078Smckusick 9*2078Smckusick px - compile px 10*2078Smckusick 11*2078Smckusick install - compile and install px in /usr/ucb 12*2078Smckusick 13*2078Smckusick clean - clean out directory 14*2078Smckusick 15*2078Smckusick print - print out a listing of px 16*2078Smckusick 17*2078Smckusick 18*2078Smckusick 19*2078SmckusickBugs and Limitations: 20*2078Smckusick 21*2078Smckusick Runtime error messages could give far more information than they 22*2078Smckusickcurrently do. (eg the actual value of a subscript which is out 23*2078Smckusickof range) 24*2078Smckusick 25*2078Smckusick It should be possible to resume execution following many of 26*2078Smckusickthe runtime errors. (eg fixed overflow, interrupt, etc) 27*2078Smckusick 28*2078Smckusick 29*2078SmckusickComparison of Pascal with C compiler 30*2078Smckusick 31*2078SmckusickIn an attempt to compare compiled versus interpreted execution speeds 32*2078Smckusickthe 'Tower of Hanoi' benchmark (see hanoi.p, hanoi.c) was run with 33*2078Smckusickthe following results: 34*2078Smckusick 35*2078SmckusickData: 36*2078Smckusick number of disks: 16 37*2078Smckusick number of moves required: 65535 38*2078Smckusick 39*2078SmckusickCompiler, Flags Compile Compile Run Run 40*2078Smckusick Time Factor Time Factor 41*2078SmckusickPi, full tests 0.4u+0.4s 1.0 42.7u 1.0 42*2078SmckusickPi, no tests 0.3u+0.3s 0.7 35.2u 1.2 43*2078SmckusickPc, unoptimized 3.8u+2.4s 7.7 5.3u 8.1 44*2078SmckusickPc, optimized 4.4u+2.3s 8.4 4.6u 9.3 45*2078SmckusickC, unoptimized 1.7u+1.8s 4.4 2.8u 15.3 46*2078SmckusickC, optimized 2.0u+2.0s 5.0 2.5u 17.1 47*2078Smckusick 48*2078SmckusickNote: The times for Pc and C were obtained by running larger 49*2078Smckusickproblems and scaling the run times down appropriately. 50