VM: fixes to make some if-else statements read better

vm/code_blocks.hpp

@@ -82,7 +82,7 @@ struct code_block {
     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];

vm/dispatch.cpp

@@ -20,8 +20,7 @@ cell factor_vm::search_lookup_hash(cell table, cell klass, cell hashcode) {
   cell bucket = array_nth(buckets, hashcode & (array_capacity(buckets) - 1));
   if (TAG(bucket) == ARRAY_TYPE)
     return search_lookup_alist(bucket, klass);
-  else
+  return bucket;
-    return bucket;
 }
 
 cell factor_vm::nth_superclass(tuple_layout* layout, fixnum echelon) {
@@ -69,10 +68,9 @@ cell factor_vm::lookup_method(cell obj, cell methods) {
   if (tag == TUPLE_TYPE) {
     if (TAG(method) == ARRAY_TYPE)
       return lookup_tuple_method(obj, method);
-    else
-      return method;
-  } else
     return method;
+  }
+  return method;
 }
 
 void factor_vm::primitive_lookup_method() {
@@ -85,8 +83,7 @@ cell factor_vm::object_class(cell obj) {
   cell tag = TAG(obj);
   if (tag == TUPLE_TYPE)
     return untag<tuple>(obj)->layout;
-  else
+  return tag_fixnum(tag);
-    return tag_fixnum(tag);
 }
 
 cell factor_vm::method_cache_hashcode(cell klass, array* array) {

vm/image.cpp

@@ -127,24 +127,24 @@ char *threadsafe_strerror(int errnum) {
 }
 
 FILE* factor_vm::open_image(vm_parameters* p) {
-  if (p->embedded_image) {
+  if (!p->embedded_image)
-    FILE* file = OPEN_READ(p->executable_path);
-    if (file == NULL) {
-      std::cout << "Cannot open embedded image" << std::endl;
-      char *msg = threadsafe_strerror(errno);
-      std::cout << "strerror:1: " << msg << std::endl;
-      free(msg);
-      exit(1);
-    }
-    embedded_image_footer footer;
-    if (!read_embedded_image_footer(file, &footer)) {
-      std::cout << "No embedded image" << std::endl;
-      exit(1);
-    }
-    safe_fseek(file, (off_t)footer.image_offset, SEEK_SET);
-    return file;
-  } else
     return OPEN_READ(p->image_path);
+
+  FILE* file = OPEN_READ(p->executable_path);
+  if (file == NULL) {
+    std::cout << "Cannot open embedded image" << std::endl;
+    char *msg = threadsafe_strerror(errno);
+    std::cout << "strerror:1: " << msg << std::endl;
+    free(msg);
+    exit(1);
+  }
+  embedded_image_footer footer;
+  if (!read_embedded_image_footer(file, &footer)) {
+    std::cout << "No embedded image" << std::endl;
+    exit(1);
+  }
+  safe_fseek(file, (off_t)footer.image_offset, SEEK_SET);
+  return file;
 }
 
 /* Read an image file from disk, only done once during startup */
@@ -209,9 +209,11 @@ bool factor_vm::save_image(const vm_char* saving_filename,
     return false;
   if (safe_fwrite(&h, sizeof(image_header), 1, file) != 1)
     return false;
-  if (safe_fwrite((void*)data->tenured->start, h.data_size, 1, file) != 1)
+  if (h.data_size > 0 &&
+      safe_fwrite((void*)data->tenured->start, h.data_size, 1, file) != 1)
     return false;
-  if (safe_fwrite((void*)code->allocator->start, h.code_size, 1, file) != 1)
+  if (h.code_size > 0 &&
+      safe_fwrite((void*)code->allocator->start, h.code_size, 1, file) != 1)
     return false;
   if (raw_fclose(file) == -1)
     return false;
@@ -244,6 +246,9 @@ void factor_vm::primitive_save_image() {
        get volatile data saved in the image. */
     active_contexts.clear();
     code->uninitialized_blocks.clear();
+
+    /* I think clearing the callback heap should be fine too. */
+    callbacks->allocator->initial_free_list(0);
   }
 
   /* do a full GC to push everything remaining into tenured space */

vm/math.hpp

@@ -9,16 +9,14 @@ static const fixnum array_size_max = ((cell)1 << (WORD_SIZE - TAG_BITS - 2));
 inline cell factor_vm::from_signed_cell(fixnum x) {
   if (x < fixnum_min || x > fixnum_max)
     return tag<bignum>(fixnum_to_bignum(x));
-  else
+  return tag_fixnum(x);
-    return tag_fixnum(x);
 }
 
 /* Allocates memory */
 inline cell factor_vm::from_unsigned_cell(cell x) {
   if (x > (cell)fixnum_max)
     return tag<bignum>(cell_to_bignum(x));
-  else
+  return tag_fixnum(x);
-    return tag_fixnum(x);
 }
 
 /* Allocates memory */

vm/objects.cpp

@@ -47,13 +47,11 @@ cell factor_vm::clone_object(cell obj_) {
 
   if (immediate_p(obj.value()))
     return obj.value();
-  else {
+  cell size = object_size(obj.value());
-    cell size = object_size(obj.value());
+  object* new_obj = allot_object(obj.type(), size);
-    object* new_obj = allot_object(obj.type(), size);
+  memcpy(new_obj, obj.untagged(), size);
-    memcpy(new_obj, obj.untagged(), size);
+  new_obj->set_hashcode(0);
-    new_obj->set_hashcode(0);
+  return tag_dynamic(new_obj);
-    return tag_dynamic(new_obj);
-  }
 }
 
 /* Allocates memory */
@@ -63,8 +61,7 @@ void factor_vm::primitive_clone() { ctx->replace(clone_object(ctx->peek())); }
 cell factor_vm::object_size(cell tagged) {
   if (immediate_p(tagged))
     return 0;
-  else
+  return untag<object>(tagged)->size();
-    return untag<object>(tagged)->size();
 }
 
 /* Allocates memory */

vm/os-unix.cpp

@@ -155,11 +155,10 @@ void synchronous_signal_handler(int signal, siginfo_t* siginfo, void* uap) {
     return;
 
   factor_vm* vm = current_vm_p();
-  if (vm) {
+  if (!vm)
-    vm->signal_number = signal;
-    vm->dispatch_signal(uap, factor::synchronous_signal_handler_impl);
-  } else
     fatal_error("Foreign thread received signal", signal);
+  vm->signal_number = signal;
+  vm->dispatch_signal(uap, factor::synchronous_signal_handler_impl);
 }
 
 void safe_write_nonblock(int fd, void* data, ssize_t size);