perf: inline public getters/setters, and use non-generic inner functions

To reduce compile-times and avoid some overhead to binary size, this will modify some of our
generic functions to use non-generic inner functions where possible. The inner functions are
marked carefully with `#[inline(never)]` to prevent being inlined by LLVM at their callsites

While looking for generic functions to optimize, I have also taken the opportunity to annotate
public non-generic getters and setters with `#[inline]` to ensure that LLVM will inline them
across crate boundaries. By default, only generic functions are automatically inlined, and
only when enabling fat LTO are constant functions reliably inlined across crate boundaries.

src/theme/mod.rs

@@ -53,36 +53,41 @@ pub(crate) static THEME: Mutex<Theme> = Mutex::new(Theme {
 });
 
 /// Currently-defined theme.
+#[inline]
 #[allow(clippy::missing_panics_doc)]
 pub fn active() -> Theme {
     THEME.lock().unwrap().clone()
 }
 
 /// Currently-defined theme type.
+#[inline]
 #[allow(clippy::missing_panics_doc)]
 pub fn active_type() -> ThemeType {
     THEME.lock().unwrap().theme_type.clone()
 }
 
 /// Preferred interface spacing parameters defined by the active theme.
-#[inline(always)]
+#[inline]
 pub fn spacing() -> Spacing {
     active().cosmic().spacing
 }
 
 /// Whether the active theme has a dark preference.
+#[inline]
 #[must_use]
 pub fn is_dark() -> bool {
     active_type().is_dark()
 }
 
 /// Whether the active theme is high contrast.
+#[inline]
 #[must_use]
 pub fn is_high_contrast() -> bool {
     active_type().is_high_contrast()
 }
 
 /// Watches for changes to the system's theme preference.
+#[cold]
 pub fn subscription(is_dark: bool) -> Subscription<crate::theme::Theme> {
     config_subscription::<_, crate::cosmic_theme::Theme>(
         (
@@ -173,6 +178,7 @@ pub enum ThemeType {
 impl ThemeType {
     /// Whether the theme has a dark preference.
     #[must_use]
+    #[inline]
     pub fn is_dark(&self) -> bool {
         match self {
             Self::Dark | Self::HighContrastDark => true,
@@ -182,6 +188,7 @@ impl ThemeType {
     }
 
     /// Whether the theme has a high contrast.
+    #[inline]
     #[must_use]
     pub fn is_high_contrast(&self) -> bool {
         match self {
@@ -191,6 +198,7 @@ impl ThemeType {
         }
     }
 
+    #[inline]
     /// Prefer dark or light theme.
     /// If `None`, the system preference is used.
     pub fn prefer_dark(&mut self, new_prefer_dark: Option<bool>) {
@@ -208,6 +216,7 @@ pub struct Theme {
 }
 
 impl Theme {
+    #[inline]
     pub fn cosmic(&self) -> &cosmic_theme::Theme {
         match self.theme_type {
             ThemeType::Dark => &COSMIC_DARK,
@@ -218,6 +227,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     pub fn dark() -> Self {
         Self {
             theme_type: ThemeType::Dark,
@@ -225,6 +235,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     pub fn light() -> Self {
         Self {
             theme_type: ThemeType::Light,
@@ -232,6 +243,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     pub fn dark_hc() -> Self {
         Self {
             theme_type: ThemeType::HighContrastDark,
@@ -239,6 +251,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     pub fn light_hc() -> Self {
         Self {
             theme_type: ThemeType::HighContrastLight,
@@ -246,6 +259,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     pub fn custom(theme: Arc<CosmicTheme>) -> Self {
         Self {
             theme_type: ThemeType::Custom(theme),
@@ -253,6 +267,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     pub fn system(theme: Arc<CosmicTheme>) -> Self {
         Self {
             theme_type: ThemeType::System {
@@ -263,6 +278,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     /// get current container
     /// can be used in a component that is intended to be a child of a `CosmicContainer`
     pub fn current_container(&self) -> &cosmic_theme::Container {
@@ -273,6 +289,7 @@ impl Theme {
         }
     }
 
+    #[inline]
     /// set the theme
     pub fn set_theme(&mut self, theme: ThemeType) {
         self.theme_type = theme;
@@ -280,6 +297,7 @@ impl Theme {
 }
 
 impl LayeredTheme for Theme {
+    #[inline]
     fn set_layer(&mut self, layer: cosmic_theme::Layer) {
         self.layer = layer;
     }

src/theme/portal.rs

@@ -1,6 +1,6 @@
-use ashpd::desktop::settings::{ColorScheme, Contrast};
 use ashpd::desktop::Color;
-use iced::futures::{self, select, FutureExt, SinkExt, StreamExt};
+use ashpd::desktop::settings::{ColorScheme, Contrast};
+use iced::futures::{self, FutureExt, SinkExt, StreamExt, select};
 use iced_futures::stream;
 use tracing::error;
 
@@ -11,6 +11,7 @@ pub enum Desktop {
     Contrast(Contrast),
 }
 
+#[cold]
 pub fn desktop_settings() -> iced_futures::Subscription<Desktop> {
     iced_futures::Subscription::run_with_id(
         std::any::TypeId::of::<Desktop>(),