Shrine/Doc/Hash.DD

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There is a symbol (hash) table for each task.  When a sym is not found, the parent task's sym table is checked.  All tasks chain back to the $FG,2$Adam$FG$ task.

TempleOS sym tables are implemented with an array of linked-lists.  A num is generated from a string by $LK,"HashStr",A="MN:HashStr"$() to index into the array of linked-lists.  Multiple strings can generate the same num, so linked-lists are built.  Newer entries overshadow older ones.

There are various types of entries.  See $LK,"Hash Entry Types",A="MN:HTT_EXPORT_SYS_SYM"$.

$FG,5$Symbol Look-up$FG$ (Used many places including the $LK,"JIT Compiler",A="FF:::/Compiler/Lex.HC,HashFind"$ and $LK,"Loader",A="FF:::/Kernel/KLoad.HC,HashFind"$.)
1) Symbol name is $LK,"hashed",A="MN:SYS_HASH_STR"$ by adding and shifting the ASCII of all chars.
2) $LK,"hash table",A="MN:CHashTable"$->body[] array is indexed.
3) Linked-lst is traversed until match of text and type of entry.
4) If not found, $LK,"hash table",A="MN:CHashTable"$->next table is searched.

Duplicate entries are allowed -- they overshadow old entries.

$FG,5$Address-to-Symbol Look-up$FG$ (Slow because not important. We could use trees.)
1) FunSeg Cache is $LK,"scanned",A="MN:FunSegCacheFind"$.
2) Hash Tables are $LK,"scanned",A="MN:FunSegFind"$.

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