Revert "VM: undoing 22bb0cfecf (#1513)"

This reverts commit e9c72baf2e.

vm/alien.cpp

@@ -5,7 +5,7 @@ namespace factor {
 // gets the address of an object representing a C pointer, with the
 // intention of storing the pointer across code which may potentially GC.
 char* factor_vm::pinned_alien_offset(cell obj) {
-  switch (tagged<object>(obj).type()) {
+  switch (TAG(obj)) {
     case ALIEN_TYPE: {
       alien* ptr = untag<alien>(obj);
       if (to_boolean(ptr->expired))
@@ -57,7 +57,7 @@ void factor_vm::primitive_displaced_alien() {
   cell alien = ctx->pop();
   cell displacement = to_cell(ctx->pop());
 
-  switch (tagged<object>(alien).type()) {
+  switch (TAG(alien)) {
     case BYTE_ARRAY_TYPE:
     case ALIEN_TYPE:
     case F_TYPE:
@@ -163,7 +163,7 @@ void factor_vm::primitive_dll_validp() {
 
 // gets the address of an object representing a C pointer
 char* factor_vm::alien_offset(cell obj) {
-  switch (tagged<object>(obj).type()) {
+  switch (TAG(obj)) {
     case BYTE_ARRAY_TYPE:
       return untag<byte_array>(obj)->data<char>();
     case ALIEN_TYPE:

vm/code_blocks.cpp

@@ -3,28 +3,23 @@
 namespace factor {
 
 static cell code_block_owner(code_block* compiled) {
-  tagged<object> owner(compiled->owner);
+  cell owner = compiled->owner;
 
   // Cold generic word call sites point to quotations that call the
   // inline-cache-miss and inline-cache-miss-tail primitives.
-  if (owner.type() == QUOTATION_TYPE) {
+  if (TAG(owner) != QUOTATION_TYPE)
-    tagged<quotation> quot(owner.as<quotation>());
+    return owner;
-    tagged<array> elements(quot->array);
 
-    FACTOR_ASSERT(array_capacity(elements.untagged()) == 5);
+  quotation* quot = untag<quotation>(owner);
-    FACTOR_ASSERT(array_nth(elements.untagged(), 4) ==
+  array* elements = untag<array>(quot->array);
-                  special_objects[PIC_MISS_WORD] ||
-                  array_nth(elements.untagged(), 4) ==
-                  special_objects[PIC_MISS_TAIL_WORD]);
 
-    tagged<wrapper> word_wrapper(array_nth(elements.untagged(), 0));
+  FACTOR_ASSERT(array_capacity(elements) == 5);
-    return word_wrapper->object;
+  wrapper* wrap = untag<wrapper>(array_nth(elements, 0));
-  }
+  return wrap->object;
-  return compiled->owner;
 }
 
 static cell compute_entry_point_address(cell obj) {
-  switch (tagged<object>(obj).type()) {
+  switch (TAG(obj)) {
     case WORD_TYPE:
       return untag<word>(obj)->entry_point;
     case QUOTATION_TYPE:
@@ -43,10 +38,9 @@ static cell compute_here_address(cell arg, cell offset, code_block* compiled) {
 }
 
 cell code_block::owner_quot() const {
-  tagged<object> executing(owner);
+  if (type() != CODE_BLOCK_OPTIMIZED && TAG(owner) == WORD_TYPE)
-  if (type() != CODE_BLOCK_OPTIMIZED && executing->type() == WORD_TYPE)
+    return untag<word>(owner)->def;
-    executing = executing.as<word>()->def;
+  return owner;
-  return executing.value();
 }
 
 // If the code block is an unoptimized quotation, we can calculate the
@@ -57,13 +51,13 @@ cell code_block::scan(factor_vm* vm, cell addr) const {
     return tag_fixnum(-1);
   }
 
-  tagged<object> obj(owner);
+  cell ptr = owner;
-  if (obj.type() == WORD_TYPE)
+  if (TAG(ptr) == WORD_TYPE)
-    obj = obj.as<word>()->def;
+    ptr = untag<word>(ptr)->def;
-  if (obj.type() != QUOTATION_TYPE)
+  if (TAG(ptr) != QUOTATION_TYPE)
     return tag_fixnum(-1);
   cell ofs = offset(addr);
-  return tag_fixnum(vm->quot_code_offset_to_scan(obj.value(), ofs));
+  return tag_fixnum(vm->quot_code_offset_to_scan(ptr, ofs));
 }
 
 cell factor_vm::compute_entry_point_pic_address(word* w, cell tagged_quot) {

vm/code_blocks.hpp

@@ -74,11 +74,13 @@ struct code_block {
   void flush_icache() { factor::flush_icache((cell)this, size()); }
 
   template <typename Iterator> void each_instruction_operand(Iterator& iter) {
-    if (to_boolean(relocation)) {
+    if (!to_boolean(relocation))
-      byte_array* rels = (byte_array*)UNTAG(relocation);
+      return;
+
+    byte_array* rels = untag<byte_array>(relocation);
 
     cell index = 0;
-      cell length = (rels->capacity >> TAG_BITS) / sizeof(relocation_entry);
+    cell length = untag_fixnum(rels->capacity) / sizeof(relocation_entry);
 
     for (cell i = 0; i < length; i++) {
       relocation_entry rel = rels->data<relocation_entry>()[i];
@@ -86,7 +88,6 @@ struct code_block {
       index += rel.number_of_parameters();
     }
   }
-  }
 
   cell offset(cell addr) const { return addr - entry_point(); }
 

vm/dispatch.cpp

@@ -40,7 +40,7 @@ cell factor_vm::lookup_tuple_method(cell obj, cell methods) {
   while (echelon >= 0) {
     cell echelon_methods = array_nth(echelons, echelon);
 
-    if (tagged<object>(echelon_methods).type() == WORD_TYPE)
+    if (TAG(echelon_methods) == WORD_TYPE)
       return echelon_methods;
     else if (to_boolean(echelon_methods)) {
       cell klass = nth_superclass(layout, echelon);

vm/objects.cpp

@@ -93,11 +93,10 @@ void factor_vm::primitive_become() {
   std::map<object*, object*> become_map;
 
   for (cell i = 0; i < capacity; i++) {
-    tagged<object> old_obj(array_nth(old_objects, i));
+    cell old_ptr = array_nth(old_objects, i);
-    tagged<object> new_obj(array_nth(new_objects, i));
+    cell new_ptr = array_nth(new_objects, i);
-
+    if (old_ptr != new_ptr)
-    if (old_obj != new_obj)
+      become_map[untag<object>(old_ptr)] = untag<object>(new_ptr);
-      become_map[old_obj.untagged()] = new_obj.untagged();
   }
 
   // Update all references to old objects to point to new objects