Use constructors to initialize state rather than lazily initializing (#9)

The old approach didn't work in the case that `hiwire_new_deduplicate`
was called before `hiwire_new`.

Author: hoodmane

src/_deduplicate.c

@@ -35,7 +35,7 @@ EM_JS(void, __hiwire_deduplicate_delete, (__externref_t map, __externref_t value
 });
 // clang-format on
 
-static void
+static void __attribute__((constructor))
 deduplicate_init()
 {
   _deduplicate_map = hiwire_intern(__hiwire_deduplicate_new());
@@ -58,9 +58,6 @@ _hiwire_deduplicate_delete(__externref_t value)
 {
   return __hiwire_deduplicate_delete(hiwire_get(_deduplicate_map), value);
 }
-
-#else
-#define deduplicate_init()
 #endif
 
 #ifdef _HIWIRE_CAN_DEDUPLICATE

src/hiwire.c

@@ -46,10 +46,6 @@ HwRef
 hiwire_new(__externref_t value)
 {
   uint index = _hiwire.freeHead;
-  if (_hiwire.slotInfoSize == 0) {
-    _hiwire_table_init();
-    deduplicate_init();
-  }
   uint needed_size = sizeof(uint[index + 1]);
   uint orig_size = sizeof(uint[_hiwire.slotInfoSize]);
   if (needed_size > orig_size) {

src/wasm_table.c

@@ -18,7 +18,7 @@ _hiwire_immortal_add(__externref_t value)
   return __builtin_wasm_table_grow(_hiwire_immortal_table, value, 1);
 }
 
-void
+static void __attribute__((constructor))
 _hiwire_table_init(void)
 {
   __builtin_wasm_table_grow(_hiwire_table, __builtin_wasm_ref_null_extern(), 1);

src/wasm_table.h

@@ -5,8 +5,6 @@ typedef unsigned int uint;
 __externref_t _hiwire_immortal_get(uint);
 uint _hiwire_immortal_add(__externref_t);
 
-void
-_hiwire_table_init(void);
 __externref_t _hiwire_get(uint);
 uint _hiwire_set(uint, __externref_t);
 void _hiwire_delete(uint);

tests/ctests/test_deduplication.c

@@ -5,23 +5,25 @@ main()
 {
   __externref_t o1 = get_obj(7);
   __externref_t o2 = get_obj(9);
-  HwRef id11 = hiwire_new(o1);
-  ASSERT(!SLOT_DEDUPLICATED(id11));
-  HwRef id12 = hiwire_new_deduplicate(o1);
-  ASSERT(SLOT_DEDUPLICATED(id12));
+  HwRef id11 = hiwire_new_deduplicate(o1);
+  ASSERT(SLOT_DEDUPLICATED(id11));
+  HwRef id12 = hiwire_new(o1);
+  ASSERT(!SLOT_DEDUPLICATED(id12));
   HwRef id13 = hiwire_new(o1);
   HwRef id14 = hiwire_new_deduplicate(o1);
   ASSERT(id11 != id12);
-  ASSERT(id12 == id14);
+  ASSERT(id11 != id13);
+  ASSERT(id12 != id13);
+  ASSERT(id11 == id14);
   ASSERT(HEAP_REF_TO_INDEX(id11) == 1);
   ASSERT(HEAP_REF_TO_INDEX(id12) == 2);
   ASSERT(HEAP_REF_TO_INDEX(id13) == 3);
-  ASSERT(HEAP_REF_TO_INDEX(id14) == 2);
-  ASSERT(SLOT_REFCOUNT(id11) == 1);
-  ASSERT(SLOT_REFCOUNT(id12) == 2);
+  ASSERT(HEAP_REF_TO_INDEX(id14) == 1);
+  ASSERT(SLOT_REFCOUNT(id11) == 2);
+  ASSERT(SLOT_REFCOUNT(id12) == 1);
   ASSERT(SLOT_REFCOUNT(id13) == 1);
-  ASSERT(!SLOT_DEDUPLICATED(id11));
-  ASSERT(SLOT_DEDUPLICATED(id12));
+  ASSERT(SLOT_DEDUPLICATED(id11));
+  ASSERT(!SLOT_DEDUPLICATED(id12));
   ASSERT(!SLOT_DEDUPLICATED(id13));
 
   HwRef id21 = hiwire_new(o2);

tests/ctests/test_deduplication.out

@@ -1,16 +1,18 @@
-PASS    !SLOT_DEDUPLICATED(id11)
-PASS    SLOT_DEDUPLICATED(id12)
+PASS    SLOT_DEDUPLICATED(id11)
+PASS    !SLOT_DEDUPLICATED(id12)
 PASS    id11 != id12
-PASS    id12 == id14
+PASS    id11 != id13
+PASS    id12 != id13
+PASS    id11 == id14
 PASS    HEAP_REF_TO_INDEX(id11) == 1
 PASS    HEAP_REF_TO_INDEX(id12) == 2
 PASS    HEAP_REF_TO_INDEX(id13) == 3
-PASS    HEAP_REF_TO_INDEX(id14) == 2
-PASS    SLOT_REFCOUNT(id11) == 1
-PASS    SLOT_REFCOUNT(id12) == 2
+PASS    HEAP_REF_TO_INDEX(id14) == 1
+PASS    SLOT_REFCOUNT(id11) == 2
+PASS    SLOT_REFCOUNT(id12) == 1
 PASS    SLOT_REFCOUNT(id13) == 1
-PASS    !SLOT_DEDUPLICATED(id11)
-PASS    SLOT_DEDUPLICATED(id12)
+PASS    SLOT_DEDUPLICATED(id11)
+PASS    !SLOT_DEDUPLICATED(id12)
 PASS    !SLOT_DEDUPLICATED(id13)
 PASS    id21 != id22
 PASS    id22 == id24