Auto merge of #11784 - heycam:atom, r=bholley

Look at nsIAtom.mHash directly rather than call Gecko_HashAtom.

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We hash Gecko-backed atoms pretty often.  Using bindgen to access to the stored hash in nsIAtom helps with perf a little.

r? @bholley

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- [ ] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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ports/geckolib/gecko_bindings/bindings.rs

@@ -35,6 +35,7 @@ use structs::nscolor;
 use structs::nsFont;
 use structs::FontFamilyList;
 use structs::FontFamilyType;
+use structs::nsIAtom;
 use heapsize::HeapSizeOf;
 unsafe impl Send for nsStyleFont {}
 unsafe impl Sync for nsStyleFont {}
@@ -121,7 +122,6 @@ unsafe impl Send for nsStyleGradientStop {}
 unsafe impl Sync for nsStyleGradientStop {}
 impl HeapSizeOf for nsStyleGradientStop { fn heap_size_of_children(&self) -> usize { 0 } }
 
-pub enum nsIAtom { }
 pub enum nsINode { }
 pub type RawGeckoNode = nsINode;
 pub enum nsIPrincipal { }

ports/geckolib/gecko_bindings/tools/regen_bindings.sh

@@ -52,7 +52,7 @@ done
 
 # Other mapped types.
 for TYPE in SheetParsingMode nsMainThreadPtrHandle nsMainThreadPtrHolder nscolor nsFont \
-            FontFamilyList FontFamilyType
+            FontFamilyList FontFamilyType nsIAtom
 do
   MAP_GECKO_TYPES=$MAP_GECKO_TYPES"-blacklist-type $TYPE "
   MAP_GECKO_TYPES=$MAP_GECKO_TYPES"-raw-line 'use structs::$TYPE;' "

ports/geckolib/glue.rs

@@ -10,9 +10,9 @@ use env_logger;
 use euclid::Size2D;
 use gecko_bindings::bindings::{RawGeckoDocument, RawGeckoElement, RawGeckoNode};
 use gecko_bindings::bindings::{RawServoStyleSet, RawServoStyleSheet, ServoComputedValues, ServoNodeData};
-use gecko_bindings::bindings::{ThreadSafePrincipalHolder, ThreadSafeURIHolder, nsIAtom};
+use gecko_bindings::bindings::{ThreadSafePrincipalHolder, ThreadSafeURIHolder};
 use gecko_bindings::ptr::{GeckoArcPrincipal, GeckoArcURI};
-use gecko_bindings::structs::SheetParsingMode;
+use gecko_bindings::structs::{SheetParsingMode, nsIAtom};
 use properties::GeckoComputedValues;
 use selector_impl::{GeckoSelectorImpl, PseudoElement, SharedStyleContext, Stylesheet};
 use std::marker::PhantomData;

ports/geckolib/string_cache/atom_macro.rs

@@ -1,4 +1,4 @@
-use gecko_bindings::bindings::nsIAtom;
+use gecko_bindings::structs::nsIAtom;
 
 use Atom;
 

ports/geckolib/string_cache/lib.rs

@@ -10,9 +10,8 @@ use gecko_bindings::bindings::Gecko_AddRefAtom;
 use gecko_bindings::bindings::Gecko_AtomEqualsUTF8IgnoreCase;
 use gecko_bindings::bindings::Gecko_Atomize;
 use gecko_bindings::bindings::Gecko_GetAtomAsUTF16;
-use gecko_bindings::bindings::Gecko_HashAtom;
 use gecko_bindings::bindings::Gecko_ReleaseAtom;
-use gecko_bindings::bindings::nsIAtom;
+use gecko_bindings::structs::nsIAtom;
 use heapsize::HeapSizeOf;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use std::borrow::Cow;
@@ -100,7 +99,7 @@ unsafe impl Sync for Atom {}
 impl Atom {
     pub fn get_hash(&self) -> u32 {
         unsafe {
-            Gecko_HashAtom(self.0)
+            (*self.0).mHash
         }
     }
 

ports/geckolib/string_cache/regen_atom_macro.py

@@ -24,7 +24,7 @@ with open(objdir_path + "/dist/include/nsGkAtomList.h") as f:
     atoms = [line_to_atom(line) for line in lines]
 
 with open("atom_macro.rs", "w") as f:
-    f.write("use gecko_bindings::bindings::nsIAtom;\n\n")
+    f.write("use gecko_bindings::structs::nsIAtom;\n\n")
     f.write("use Atom;\n\n")
     f.write("pub fn unsafe_atom_from_static(ptr: *mut nsIAtom) -> Atom { unsafe { Atom::from_static(ptr) } }\n\n")
     for atom in atoms:

ports/geckolib/wrapper.rs

@@ -9,7 +9,6 @@ use gecko_bindings::bindings::Gecko_ClassOrClassList;
 use gecko_bindings::bindings::Gecko_GetElementId;
 use gecko_bindings::bindings::Gecko_GetNodeData;
 use gecko_bindings::bindings::ServoNodeData;
-use gecko_bindings::bindings::nsIAtom;
 use gecko_bindings::bindings::{Gecko_ElementState, Gecko_GetAttrAsUTF8, Gecko_GetDocumentElement};
 use gecko_bindings::bindings::{Gecko_GetFirstChild, Gecko_GetFirstChildElement};
 use gecko_bindings::bindings::{Gecko_GetLastChild, Gecko_GetLastChildElement};
@@ -21,6 +20,7 @@ use gecko_bindings::bindings::{Gecko_IsUnvisitedLink, Gecko_IsVisitedLink};
 #[allow(unused_imports)] // Used in commented-out code.
 use gecko_bindings::bindings::{Gecko_LocalName, Gecko_Namespace, Gecko_NodeIsElement, Gecko_SetNodeData};
 use gecko_bindings::bindings::{RawGeckoDocument, RawGeckoElement, RawGeckoNode};
+use gecko_bindings::structs::nsIAtom;
 use libc::uintptr_t;
 use properties::GeckoComputedValues;
 use selector_impl::{GeckoSelectorImpl, NonTSPseudoClass, PrivateStyleData};