119 lines
1.8 KiB
C
119 lines
1.8 KiB
C
#include "defs.h"
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/* TABLE_SIZE is the number of entries in the symbol table. */
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/* TABLE_SIZE must be a power of two. */
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#define TABLE_SIZE 1024
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bucket **symbol_table;
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bucket *first_symbol;
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bucket *last_symbol;
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int
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hash(name)
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char *name;
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{
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register char *s;
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register int c, k;
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assert(name && *name);
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s = name;
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k = *s;
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while (c = *++s)
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k = (31*k + c) & (TABLE_SIZE - 1);
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return (k);
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}
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bucket *
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make_bucket(name)
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char *name;
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{
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register bucket *bp;
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assert(name);
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bp = (bucket *) MALLOC(sizeof(bucket));
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if (bp == 0) no_space();
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bp->link = 0;
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bp->next = 0;
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bp->name = MALLOC(strlen(name) + 1);
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if (bp->name == 0) no_space();
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bp->tag = 0;
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bp->value = UNDEFINED;
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bp->index = 0;
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bp->prec = 0;
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bp-> class = UNKNOWN;
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bp->assoc = TOKEN;
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if (bp->name == 0) no_space();
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strcpy(bp->name, name);
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return (bp);
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}
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bucket *
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lookup(name)
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char *name;
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{
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register bucket *bp, **bpp;
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bpp = symbol_table + hash(name);
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bp = *bpp;
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while (bp)
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{
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if (strcmp(name, bp->name) == 0) return (bp);
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bpp = &bp->link;
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bp = *bpp;
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}
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*bpp = bp = make_bucket(name);
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last_symbol->next = bp;
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last_symbol = bp;
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return (bp);
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}
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create_symbol_table()
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{
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register int i;
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register bucket *bp;
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symbol_table = (bucket **) MALLOC(TABLE_SIZE*sizeof(bucket *));
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if (symbol_table == 0) no_space();
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for (i = 0; i < TABLE_SIZE; i++)
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symbol_table[i] = 0;
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bp = make_bucket("error");
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bp->index = 1;
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bp->class = TERM;
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first_symbol = bp;
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last_symbol = bp;
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symbol_table[hash("error")] = bp;
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}
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free_symbol_table()
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{
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FREE(symbol_table);
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symbol_table = 0;
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}
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free_symbols()
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{
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register bucket *p, *q;
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for (p = first_symbol; p; p = q)
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{
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q = p->next;
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FREE(p);
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}
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}
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