projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 5292845a KB |
1 | /* |
| 2 | * Copyright (c) 1982 Regents of the University of California | |
| 3 | * @(#)assyms.h 4.5 6/30/83 | |
| 4 | */ | |
| 5 | /* | |
| 6 | * To speed up walks through symbols defined in a particular | |
| 7 | * segment, we buil up a table of pointers into the symbol table | |
| 8 | * and a table of delimiters for each segment. The delimiter for | |
| 9 | * the particular segment points to the first word in that segment. | |
| 10 | */ | |
| 11 | ||
| 12 | extern struct symtab **symptrs; /*dynamically allocated*/ | |
| 13 | extern struct symtab **symdelim[NLOC + NLOC + 1]; | |
| 14 | extern struct symtab **symptrub; | |
| 15 | extern int nsyms; /*number in the symbol table*/ | |
| 16 | extern int njxxx; /*the number of jxxx entries in the table*/ | |
| 17 | extern int nforgotten; /*how many entries erroneously entered*/ | |
| 18 | extern int nlabels; /*how many labels in the symbol table*/ | |
| 19 | extern int hshused; /*how many hash slots used*/ | |
| 20 | ||
| 21 | #define SEGITERATE(segno, start, end, copointer, walkpointer, ubpointer, direction) \ | |
| 22 | for(copointer = start == 0? symdelim[segno]:start,\ | |
| 23 | ubpointer = end == 0 ? *symdelim[segno+1] : *(symdelim[segno]-1),\ | |
| 24 | walkpointer = *copointer;\ | |
| 25 | walkpointer != ubpointer;\ | |
| 26 | walkpointer = * direction copointer) | |
| 27 | ||
| 28 | #define SYMITERATE(copointer, walkpointer) \ | |
| 29 | for(copointer = symptrs, \ | |
| 30 | walkpointer = *copointer; \ | |
| 31 | copointer < symptrub; \ | |
| 32 | walkpointer = * ++ copointer) | |
| 33 | /* | |
| 34 | * Symbols are allocated in non contiguous chunks by extending | |
| 35 | * the data area. | |
| 36 | */ | |
| 37 | ||
| 38 | #define SYMDALLOP 200 | |
| 39 | struct allocbox{ | |
| 40 | struct allocbox *nextalloc; | |
| 41 | struct symtab symslots[SYMDALLOP]; | |
| 42 | }; | |
| 43 | ||
| 44 | /* | |
| 45 | * Names are allocated in a dynamically extensible string pool. | |
| 46 | */ | |
| 47 | struct strpool{ | |
| 48 | struct strpool *str_next; | |
| 49 | int str_nalloc; | |
| 50 | char str_names[STRPOOLDALLOP]; | |
| 51 | }; | |
| 52 | ||
| 53 | extern struct strpool *strplhead; | |
| 54 | ||
| 55 | extern struct allocbox *allochead; | |
| 56 | extern struct allocbox *alloctail; | |
| 57 | extern struct symtab *nextsym; | |
| 58 | extern struct allocbox *newbox; | |
| 59 | extern char *namebuffer; | |
| 60 | extern int symsleft; | |
| 61 | ||
| 62 | #define ALLOCQTY sizeof (struct allocbox) | |
| 63 | /* | |
| 64 | * Iterate through all symbols in the symbol table in declaration | |
| 65 | * order | |
| 66 | */ | |
| 67 | #define DECLITERATE(allocwalk, walkpointer, ubpointer) \ | |
| 68 | for(allocwalk = allochead; \ | |
| 69 | allocwalk != 0; \ | |
| 70 | allocwalk = allocwalk->nextalloc) \ | |
| 71 | for (walkpointer = &allocwalk->symslots[0],\ | |
| 72 | ubpointer = &allocwalk->symslots[SYMDALLOP], \ | |
| 73 | ubpointer = ubpointer > ( (struct symtab *)alloctail) \ | |
| 74 | ? nextsym : ubpointer ;\ | |
| 75 | walkpointer < ubpointer; \ | |
| 76 | walkpointer++ ) | |
| 77 | /* | |
| 78 | * The hash table is segmented, and dynamically extendable. | |
| 79 | * We have a linked list of hash table segments; within each | |
| 80 | * segment we use a quadratic rehash that touches no more than 1/2 | |
| 81 | * of the buckets in the hash table when probing. | |
| 82 | * If the probe does not find the desired symbol, it moves to the | |
| 83 | * next segment, or allocates a new segment. | |
| 84 | * | |
| 85 | * Hash table segments are kept on the linked list with the first | |
| 86 | * segment always first (that contains the reserved words) and | |
| 87 | * the last added segment immediately after the first segment | |
| 88 | * to hopefully gain something by locality of reference. | |
| 89 | */ | |
| 90 | struct hashdallop { | |
| 91 | int h_nused; | |
| 92 | struct hashdallop *h_next; | |
| 93 | struct symtab *h_htab[NHASH]; | |
| 94 | }; |