rewrite for compability

reimplement/newset.c

@@ -2,24 +2,11 @@
 #include "stdio.h"
 #include "system.h"
 
-uint64_t hash(const char* str) {
-  uint64_t h = 0xcbf29ce484222325ULL;
-
-  while (*str) {
-    h ^= (uint64_t)(unsigned char)(*str++);
-    h *= 0x100000001b3ULL;
-  }
-
-  return h;
-}
-
-// ---
-
 struct set {
   size_t cnt;
   struct symbols {
     const char* str;
-    uint64_t hash;
+    int hash;
   }* symbols_v;
 };
 
@@ -61,6 +48,20 @@ struct set* set_free(struct set* set) {
 
 // ---
 
+static unsigned int hash(const char* str) {
+  unsigned int hash = 0x9e3779b9;
+  const unsigned char* p = (const unsigned char*)str;
+  while (*p) {
+    hash += *p++;
+    hash += (hash << 10);
+    hash ^= (hash >> 6);
+  }
+  hash += (hash << 3);
+  hash ^= (hash >> 11);
+  hash += (hash << 15);
+  return hash;
+}
+
 int cmp(const void* arg1, const void* arg2) {
   const struct symbols* s1 = arg1;
   const struct symbols* s2 = arg2;
@@ -76,9 +77,9 @@ const char* set_fini(struct set* set, int bpp) {
 
   assert(set != NULL);
   assert(set->cnt > 0);
-  assert(bpp >= 10 && bpp <= 63);
+  assert(bpp >= 10 && bpp <= 32);
 
-  uint64_t mask = (1ULL << bpp) - 1;
+  int mask = (bpp < 32) ? (1u << bpp) - 1 : ~0u;
 
   for (size_t i = 0; i < set->cnt; ++i) {
     set->symbols_v[i].hash = hash(set->symbols_v[i].str) & mask;
@@ -86,6 +87,7 @@ const char* set_fini(struct set* set, int bpp) {
 
   qsort(set->symbols_v, set->cnt, sizeof *set->symbols_v, cmp);
 
+  // warn on hash collizions
   for (size_t i = 0; i < set->cnt - 1; ++i) {
     if (set->symbols_v[i].hash != set->symbols_v[i + 1].hash) continue;
     if (!strcmp(set->symbols_v[i].str, set->symbols_v[i + 1].str)) continue;
@@ -94,9 +96,10 @@ const char* set_fini(struct set* set, int bpp) {
             set->symbols_v[i + 1].str);
   }
 
-  uint64_t unique_hash[set->cnt];
+  int unique_hash[set->cnt];
   size_t unique_cnt = 0;
 
+  // delete duplicates
   for (size_t i = 0; i < set->cnt; ++i) {
     while (i + 1 < set->cnt && set->symbols_v[i].hash == set->symbols_v[i + 1].hash) {
       ++i;