use more simple hashing algorithm, made namelist generation dependant on a #define

diff --git a/lang/cem/cemcom.ansi/LLlex.c b/lang/cem/cemcom.ansi/LLlex.c
index 70b1693..b5ca0e0 100644 (file)
--- a/lang/cem/cemcom.ansi/LLlex.c
+++ b/lang/cem/cemcom.ansi/LLlex.c
@@ -316,7 +316,7 @@ garbage:
                do      {                       /* read the identifier  */
                        if (++pos < idfsize) {
                                *tg++ = ch;
-                               hash = ENHASH(hash, ch, pos);
+                               hash = ENHASH(hash, ch);
                        }
                        ch = GetChar();
                } while (in_idf(ch));

diff --git a/lang/cem/cemcom.ansi/idf.c b/lang/cem/cemcom.ansi/idf.c
index edfe141..880bc5f 100644 (file)
--- a/lang/cem/cemcom.ansi/idf.c
+++ b/lang/cem/cemcom.ansi/idf.c
@@ -137,7 +137,7 @@ str2idf(tg)
        hash = STARTHASH();
        while (++pos < idfsize && (ch = *cp++)) {
                *ncp++ = ch;
-               hash = ENHASH(hash, ch, pos);
+               hash = ENHASH(hash, ch);
        }
        hash = STOPHASH(hash);
        *ncp++ = '\0';
@@ -757,18 +757,3 @@ free_formals(fm)
                fm = tmp;
        }
 }
-
-char hmask[IDFSIZE];
-
-init_hmask()
-{
-       /*      A simple congruence random number generator, as
-               described in Knuth, vol 2.
-       */
-       register int h, rnd = HASH_X;
-       
-       for (h = 0; h < IDFSIZE; h++)   {
-               hmask[h] = rnd;
-               rnd = (HASH_A * rnd + HASH_C) & HASHMASK;
-       }
-}

diff --git a/lang/cem/cemcom.ansi/idf.str b/lang/cem/cemcom.ansi/idf.str
index 640d933..e5fcdcd 100644 (file)
--- a/lang/cem/cemcom.ansi/idf.str
+++ b/lang/cem/cemcom.ansi/idf.str
@@ -7,24 +7,11 @@
 
 #include       "nopp.h"
 
-/*     Since the % operation in the calculation of the hash function
-       turns out to be expensive, it is replaced by the cheaper XOR (^).
-       Each character of the identifier is xored with an 8-bit mask which
-       depends on the position of the character; the sum of these results
-       is the hash value.  The random masks are obtained from a
-       congruence generator in idf.c.
-*/
+#define        HASHSIZE        307     /* must be odd */
 
-#define        HASHSIZE        256     /* must be a power of 2 */
-#define        HASH_X          0253    /* Knuth's X */
-#define        HASH_A          77      /* Knuth's a */
-#define        HASH_C          153     /* Knuth's c */
-
-extern char hmask[];           /* the random masks */
-#define        HASHMASK                (HASHSIZE-1)    /* since it is a power of 2 */
 #define        STARTHASH()             (0)
-#define        ENHASH(hs,ch,ps)        (hs + (ch ^ hmask[ps]))
-#define        STOPHASH(hs)            (hs & HASHMASK)
+#define        ENHASH(hs,ch)           ((hs << 2) + ch)
+#define        STOPHASH(hs)            ((unsigned)hs % HASHSIZE)
 
 struct idf     {
        struct idf *next;

diff --git a/lang/cem/cemcom.ansi/main.c b/lang/cem/cemcom.ansi/main.c
index b25f219..d52d600 100644 (file)
--- a/lang/cem/cemcom.ansi/main.c
+++ b/lang/cem/cemcom.ansi/main.c
@@ -83,7 +83,6 @@ main(argc, argv)
        /* parse and interpret the command line options */
        prog_name = argv[0];
 
-       init_hmask();
 #ifndef NOPP
        inctable = (char **) Malloc(10 * sizeof(char *));
        inctable[0] = "";
@@ -125,7 +124,9 @@ main(argc, argv)
 
 char *source = 0;
 
+#ifdef GEN_NM_LIST
 char *nmlist = 0;
+#endif GEN_NM_LIST
 
 compile(argc, argv)
        char *argv[];
@@ -157,15 +158,21 @@ compile(argc, argv)
        case 2:
                destination = argv[1];
                break;
+#ifdef GEN_NM_LIST
        case 3:
                nmlist = argv[2];
                destination = argv[1];
                break;
+#endif GEN_NM_LIST
 #endif LINT
 
        default:
 #ifndef        LINT
+#ifdef GEN_NM_LIST
                fatal("use: %s source destination [namelist]", prog_name);
+#else GEN_NM_LIST
+               fatal("use: %s source destination", prog_name);
+#endif GEN_NM_LIST
 #else  LINT
                fatal("use: %s source", prog_name);
 #endif LINT

diff --git a/lang/cem/cemcom.ansi/replace.c b/lang/cem/cemcom.ansi/replace.c
index c800ae1..7fcc8dc 100644 (file)
--- a/lang/cem/cemcom.ansi/replace.c
+++ b/lang/cem/cemcom.ansi/replace.c
@@ -313,7 +313,7 @@ actual(repl)
                        do {
                                if (++pos < idfsize) {
                                        *p++ = ch;
-                                       hash = ENHASH(hash, ch, pos);
+                                       hash = ENHASH(hash, ch);
                                }
                                ch = GetChar();
                        } while (in_idf(ch));

diff --git a/lang/cem/cemcom.ansi/stack.c b/lang/cem/cemcom.ansi/stack.c
index b7d5b70..94d7661 100644 (file)
--- a/lang/cem/cemcom.ansi/stack.c
+++ b/lang/cem/cemcom.ansi/stack.c
@@ -179,7 +179,9 @@ unstack_world()
        lint_global_level(local_level);
 #endif LINT
 
+#ifdef GEN_NM_LIST
        open_name_list();
+#endif GEN_NM_LIST
 
        while (se)      {
                register struct idf *idf = se->se_idf;
@@ -227,8 +229,10 @@ unstack_world()
                    && !def->df_initialized) {
                        /* space must be allocated */
                        bss(idf);
+#ifdef GEN_NM_LIST
                        if (def->df_sc != STATIC)
                                namelist(idf->id_text); /* may be common */
+#endif GEN_NM_LIST
                        def->df_alloc = ALLOC_DONE;     /* see Note below */
                }
                se = se->next;
@@ -247,6 +251,7 @@ unstack_world()
        */
 }
 
+#ifdef GEN_NM_LIST
 /*     A list of potential common names is kept, to be fed to
        an understanding loader.  The list is written to a file
        the name of which is nmlist.  If nmlist == NULL, no name
@@ -269,3 +274,4 @@ namelist(nm)
                sys_write(nfp, "\n", 1);
        }
 }
+#endif GEN_NM_LIST