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Fix basic output target to keep lines below 249 characters The line length limiter in the basic output was not properly moving to the next before 249 characters, which is the limit Color Basic can read in an ASCII basic program. Changed the line limiter to 240 from 247 to account for a possible 5 digit number plus a comma and just a bit of extra breathing space.
author William Astle <lost@l-w.ca>
date Thu, 16 Jun 2022 13:55:34 -0600
parents 2c24602be78f
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
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1 LWASM Internals
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2 ===============
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3
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4 LWASM is a table-driven assembler that notionally uses two passes. However,
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5 it implements its assembly in several passes as follows.
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6
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7 Pass 1
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8 ------
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10 This pass reads the entire source code and parses each line into an internal
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11 representation. Macros, file inclusions, and conditional assembly
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12 instructions are resolved at this point as well. Instructions with known
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13 sizes will have their sizes resolved at this point.
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15 Pass 2
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16 ------
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18 Check all exported symbols for validity and set them as imports if the
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19 assembler state says so. Also resolve all symbol references in all
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20 expressions to be direct references either to the symbol table or
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21 to the import list.
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23 Pass 3
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24 ------
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26 This pass resolves all instruction sizes that can be resolved without
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27 forcing any instruction sizes. This pass will run repeatedly until no
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28 no new resolution occurs.
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30 Pass 4
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31 ------
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33 Work through all un-resolved instructions and force sizes. After each size
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34 is forced, try re-resolving all other instructions. This is done starting
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35 at the beginning of the source and working forward. If any instruction does
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36 not resolve when forced, an error will be thrown.
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37
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38 Pass 5
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39 ------
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41 Constantize all line addresses and throw errors if any cannot be. This
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42 pass will repeat until no further lines addresses are reduced to constants
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43 at which time all lines will be checked for constant-ness.
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45 Pass 6
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46 ------
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48 Finalize all expressions related to instructions. Carp about any that
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49 cannot be reduced to a usable form. That means, for the non-object target
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50 all expressions must resolve to a constant. For the object form, all
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51 expressions must resolve to symbol references and constants. Those symbol
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52 references may be internal or external.
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54 Pass 7
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55 ------
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57 Emit object code for each line for later output.