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Allow trailing ' or " on ascii constants Allow for 'c' or "cc" instead of just 'c and "cc for ascii constants. This adds additional compatibility for some unusual source files while not causing well formed files to fail.
author Tom LeMense <tlemense@yahoo.com>
date Fri, 11 Apr 2014 21:50:47 -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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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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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.