Bug 1298588 part 14. Remove ComputedValues::initial_values for stylo.…

… r=bholley

components/style/properties/gecko.mako.rs

@@ -55,7 +55,6 @@ use properties::longhands;
 use std::fmt::{self, Debug};
 use std::mem::{transmute, zeroed};
 use std::ptr;
-use std::sync::atomic::{ATOMIC_USIZE_INIT, AtomicUsize, Ordering};
 use std::sync::Arc;
 use std::cmp;
 
@@ -113,13 +112,6 @@ impl ComputedValues {
         }
     }
 
-    pub fn initial_values() -> &'static Self {
-        unsafe {
-            debug_assert!(!raw_initial_values().is_null());
-            &*raw_initial_values()
-        }
-    }
-
     pub fn default_values(pres_context: RawGeckoPresContextBorrowed) -> Arc<Self> {
         Arc::new(ComputedValues {
             custom_properties: None,
@@ -132,25 +124,6 @@ impl ComputedValues {
         })
     }
 
-    pub unsafe fn initialize() {
-        debug_assert!(raw_initial_values().is_null());
-        set_raw_initial_values(Box::into_raw(Box::new(ComputedValues {
-            % for style_struct in data.style_structs:
-               ${style_struct.ident}: style_structs::${style_struct.name}::initial(),
-            % endfor
-            custom_properties: None,
-            shareable: true,
-            writing_mode: WritingMode::empty(),
-            root_font_size: longhands::font_size::get_initial_value(),
-        })));
-    }
-
-    pub unsafe fn shutdown() {
-        debug_assert!(!raw_initial_values().is_null());
-        let _ = Box::from_raw(raw_initial_values());
-        set_raw_initial_values(ptr::null_mut());
-    }
-
     % for style_struct in data.style_structs:
     #[inline]
     pub fn clone_${style_struct.name_lower}(&self) -> Arc<style_structs::${style_struct.name}> {
@@ -2662,13 +2635,3 @@ pub unsafe extern "C" fn Servo_GetStyleVariables(_cv: ServoComputedValuesBorrowe
     &*EMPTY_VARIABLES_STRUCT
 }
 
-// To avoid UB, we store the initial values as a atomic. It would be nice to
-// store them as AtomicPtr, but we can't have static AtomicPtr without const
-// fns, which aren't in stable Rust.
-static INITIAL_VALUES_STORAGE: AtomicUsize = ATOMIC_USIZE_INIT;
-unsafe fn raw_initial_values() -> *mut ComputedValues {
-    INITIAL_VALUES_STORAGE.load(Ordering::Relaxed) as *mut ComputedValues
-}
-unsafe fn set_raw_initial_values(v: *mut ComputedValues) {
-    INITIAL_VALUES_STORAGE.store(v as usize, Ordering::Relaxed);
-}

ports/geckolib/glue.rs

@@ -82,17 +82,12 @@ pub extern "C" fn Servo_Initialize() -> () {
     // See https://doc.rust-lang.org/log/env_logger/index.html for instructions.
     env_logger::init().unwrap();
 
-    // Allocate our default computed values.
-    unsafe { ComputedValues::initialize(); }
-
     // Pretend that we're a Servo Layout thread, to make some assertions happy.
     thread_state::initialize(thread_state::LAYOUT);
 }
 
 #[no_mangle]
 pub extern "C" fn Servo_Shutdown() -> () {
-    // Destroy our default computed values.
-    unsafe { ComputedValues::shutdown(); }
 }
 
 fn create_shared_context(per_doc_data: &PerDocumentStyleDataImpl) -> SharedStyleContext {
@@ -118,15 +113,6 @@ fn create_shared_context(per_doc_data: &PerDocumentStyleDataImpl) -> SharedStyle
 
 fn traverse_subtree(element: GeckoElement, raw_data: RawServoStyleSetBorrowed,
                     unstyled_children_only: bool) {
-    // Force the creation of our lazily-constructed initial computed values on
-    // the main thread, since it's not safe to call elsewhere.
-    //
-    // FIXME(bholley): this should move into Servo_Initialize as soon as we get
-    // rid of the HackilyFindSomeDeviceContext stuff that happens during
-    // initial_values computation, since that stuff needs to be called further
-    // along in startup than the sensible place to call Servo_Initialize.
-    ComputedValues::initial_values();
-
     // When new content is inserted in a display:none subtree, we will call into
     // servo to try to style it. Detect that here and bail out.
     if let Some(parent) = element.parent_element() {