Avoid copying FontPalette and FontVariantAlternates

https://bugs.webkit.org/show_bug.cgi?id=273568
<rdar://problem/127380343>

Reviewed by Chris Dumez.

Reduce unnecessary copies in our font handling code:
(1) FontPalette is a struct containing an enum and an AtomString, and should be returned
    by const reference to avoid copying that string.
(2) FontVariantAlternates is lightweight, containing only a `Markable`, but the
    `Markable` is holding a very heavy-weight object that contains Vectors of Strings,
    and Strings.

* Source/WebCore/css/CSSFontFace.h:
* Source/WebCore/css/CSSFontFaceSet.cpp:
(WebCore::CSSFontFaceSet::fontFace):
* Source/WebCore/css/CSSFontFaceSet.h:
* Source/WebCore/platform/graphics/FontDescription.h:
(WebCore::FontDescription::variantAlternates const):
(WebCore::FontDescription::fontPalette const):
(WebCore::FontDescription::setVariantAlternates):
(WebCore::FontDescription::setFontPalette):
* Source/WebCore/platform/text/TextFlags.cpp:
(WebCore::operator<<):
* Source/WebCore/platform/text/TextFlags.h:
* Source/WebCore/rendering/style/RenderStyle.cpp:
(WebCore::RenderStyle::setFontPalette):
* Source/WebCore/rendering/style/RenderStyle.h:
* Source/WebCore/rendering/style/RenderStyleInlines.h:
(WebCore::RenderStyle::fontPalette const):
* Source/WebCore/style/StyleBuilderCustom.h:
(WebCore::Style::BuilderCustom::applyValueFontVariantAlternates):

Canonical link: https://commits.webkit.org/278351@main

Source/WebCore/animation/CSSPropertyAnimation.cpp

@@ -3930,7 +3930,7 @@ CSSPropertyAnimationWrapperMap::CSSPropertyAnimationWrapperMap()
         new DiscretePropertyWrapper<StyleColorScheme>(CSSPropertyColorScheme, &RenderStyle::colorScheme, &RenderStyle::setColorScheme),
 #endif
         new PropertyWrapperAspectRatio,
-        new DiscretePropertyWrapper<FontPalette>(CSSPropertyFontPalette, &RenderStyle::fontPalette, &RenderStyle::setFontPalette),
+        new DiscretePropertyWrapper<const FontPalette&>(CSSPropertyFontPalette, &RenderStyle::fontPalette, &RenderStyle::setFontPalette),
 
         new OffsetPathWrapper,
         new OffsetDistanceWrapper,
@@ -3954,7 +3954,7 @@ CSSPropertyAnimationWrapperMap::CSSPropertyAnimationWrapperMap()
         new DiscreteFontDescriptionTypedWrapper<FontSynthesisLonghandValue>(CSSPropertyFontSynthesisWeight, &FontCascadeDescription::fontSynthesisWeight, &FontCascadeDescription::setFontSynthesisWeight),
         new DiscreteFontDescriptionTypedWrapper<FontSynthesisLonghandValue>(CSSPropertyFontSynthesisStyle, &FontCascadeDescription::fontSynthesisStyle, &FontCascadeDescription::setFontSynthesisStyle),
         new DiscreteFontDescriptionTypedWrapper<FontSynthesisLonghandValue>(CSSPropertyFontSynthesisSmallCaps, &FontCascadeDescription::fontSynthesisSmallCaps, &FontCascadeDescription::setFontSynthesisSmallCaps),
-        new DiscreteFontDescriptionTypedWrapper<FontVariantAlternates>(CSSPropertyFontVariantAlternates, &FontCascadeDescription::variantAlternates, &FontCascadeDescription::setVariantAlternates),
+        new DiscreteFontDescriptionTypedWrapper<const FontVariantAlternates&>(CSSPropertyFontVariantAlternates, &FontCascadeDescription::variantAlternates, &FontCascadeDescription::setVariantAlternates),
         new FontVariantEastAsianWrapper,
         new FontVariantLigaturesWrapper,
         new FontVariantNumericWrapper,

Source/WebCore/platform/graphics/FontDescription.h

@@ -50,7 +50,7 @@ class FontDescription {
     std::optional<FontSelectionValue> italic() const { return m_fontSelectionRequest.slope; }
     FontSelectionValue stretch() const { return m_fontSelectionRequest.width; }
     FontSelectionValue weight() const { return m_fontSelectionRequest.weight; }
-    FontSelectionRequest fontSelectionRequest() const { return m_fontSelectionRequest; }
+    const FontSelectionRequest& fontSelectionRequest() const { return m_fontSelectionRequest; }
     TextRenderingMode textRenderingMode() const { return static_cast<TextRenderingMode>(m_textRendering); }
     TextSpacingTrim textSpacingTrim() const { return m_textSpacingTrim; }
     TextAutospace textAutospace() const { return m_textAutospace; }
@@ -80,7 +80,7 @@ class FontDescription {
     FontVariantNumericFraction variantNumericFraction() const { return static_cast<FontVariantNumericFraction>(m_variantNumericFraction); }
     FontVariantNumericOrdinal variantNumericOrdinal() const { return static_cast<FontVariantNumericOrdinal>(m_variantNumericOrdinal); }
     FontVariantNumericSlashedZero variantNumericSlashedZero() const { return static_cast<FontVariantNumericSlashedZero>(m_variantNumericSlashedZero); }
-    FontVariantAlternates variantAlternates() const { return m_variantAlternates; }
+    const FontVariantAlternates& variantAlternates() const { return m_variantAlternates; }
     FontVariantEastAsianVariant variantEastAsianVariant() const { return static_cast<FontVariantEastAsianVariant>(m_variantEastAsianVariant); }
     FontVariantEastAsianWidth variantEastAsianWidth() const { return static_cast<FontVariantEastAsianWidth>(m_variantEastAsianWidth); }
     FontVariantEastAsianRuby variantEastAsianRuby() const { return static_cast<FontVariantEastAsianRuby>(m_variantEastAsianRuby); }
@@ -108,7 +108,7 @@ class FontDescription {
     FontStyleAxis fontStyleAxis() const { return m_fontStyleAxis ? FontStyleAxis::ital : FontStyleAxis::slnt; }
     AllowUserInstalledFonts shouldAllowUserInstalledFonts() const { return static_cast<AllowUserInstalledFonts>(m_shouldAllowUserInstalledFonts); }
     bool shouldDisableLigaturesForSpacing() const { return m_shouldDisableLigaturesForSpacing; }
-    FontPalette fontPalette() const { return m_fontPalette; }
+    const FontPalette& fontPalette() const { return m_fontPalette; }
     FontSizeAdjust fontSizeAdjust() const { return m_sizeAdjust; }
 
     void setComputedSize(float s) { m_computedSize = clampToFloat(s); }
@@ -139,7 +139,8 @@ class FontDescription {
     void setVariantNumericFraction(FontVariantNumericFraction variant) { m_variantNumericFraction = enumToUnderlyingType(variant); }
     void setVariantNumericOrdinal(FontVariantNumericOrdinal variant) { m_variantNumericOrdinal = enumToUnderlyingType(variant); }
     void setVariantNumericSlashedZero(FontVariantNumericSlashedZero variant) { m_variantNumericSlashedZero = enumToUnderlyingType(variant); }
-    void setVariantAlternates(FontVariantAlternates variant) { m_variantAlternates = variant; }
+    void setVariantAlternates(const FontVariantAlternates& variant) { m_variantAlternates = variant; }
+    void setVariantAlternates(FontVariantAlternates&& variant) { m_variantAlternates = WTFMove(variant); }
     void setVariantEastAsianVariant(FontVariantEastAsianVariant variant) { m_variantEastAsianVariant = enumToUnderlyingType(variant); }
     void setVariantEastAsianWidth(FontVariantEastAsianWidth variant) { m_variantEastAsianWidth = enumToUnderlyingType(variant); }
     void setVariantEastAsianRuby(FontVariantEastAsianRuby variant) { m_variantEastAsianRuby = enumToUnderlyingType(variant); }
@@ -148,7 +149,7 @@ class FontDescription {
     void setFontStyleAxis(FontStyleAxis axis) { m_fontStyleAxis = axis == FontStyleAxis::ital; }
     void setShouldAllowUserInstalledFonts(AllowUserInstalledFonts shouldAllowUserInstalledFonts) { m_shouldAllowUserInstalledFonts = enumToUnderlyingType(shouldAllowUserInstalledFonts); }
     void setShouldDisableLigaturesForSpacing(bool shouldDisableLigaturesForSpacing) { m_shouldDisableLigaturesForSpacing = shouldDisableLigaturesForSpacing; }
-    void setFontPalette(FontPalette fontPalette) { m_fontPalette = fontPalette; }
+    void setFontPalette(const FontPalette& fontPalette) { m_fontPalette = fontPalette; }
     void setFontSizeAdjust(FontSizeAdjust fontSizeAdjust) { m_sizeAdjust = fontSizeAdjust; }
 
     static AtomString platformResolveGenericFamily(UScriptCode, const AtomString& locale, const AtomString& familyName);

Source/WebCore/platform/text/TextFlags.cpp

@@ -74,7 +74,7 @@ WTF::TextStream& operator<<(TextStream& ts, Kerning kerning)
     return ts;
 }
 
-WTF::TextStream& operator<<(TextStream& ts, FontVariantAlternates alternates)
+WTF::TextStream& operator<<(TextStream& ts, const FontVariantAlternates& alternates)
 {
     if (alternates.isNormal())
         ts << "normal";

Source/WebCore/platform/text/TextFlags.h

@@ -238,7 +238,7 @@ class FontVariantAlternates {
     FontVariantAlternates() = default;
 };
 
-WTF::TextStream& operator<<(WTF::TextStream&, FontVariantAlternates);
+WTF::TextStream& operator<<(WTF::TextStream&, const FontVariantAlternates&);
 
 enum class FontVariantEastAsianVariant : uint8_t {
     Normal,

Source/WebCore/rendering/style/RenderStyle.cpp

@@ -2923,7 +2923,7 @@ void RenderStyle::setFontItalic(std::optional<FontSelectionValue> value)
     fontCascade().update(selector);
 }
 
-void RenderStyle::setFontPalette(FontPalette value)
+void RenderStyle::setFontPalette(const FontPalette& value)
 {
     auto selector = fontCascade().fontSelector();
     auto description = fontDescription();

Source/WebCore/rendering/style/RenderStyle.h

@@ -554,7 +554,7 @@ class RenderStyle final : public CanMakeCheckedPtr<RenderStyle> {
     inline FontSelectionValue fontWeight() const;
     inline FontSelectionValue fontStretch() const;
     inline std::optional<FontSelectionValue> fontItalic() const;
-    inline FontPalette fontPalette() const;
+    inline const FontPalette& fontPalette() const;
     inline FontSizeAdjust fontSizeAdjust() const;
 
     inline const Length& textIndent() const;
@@ -1247,7 +1247,7 @@ class RenderStyle final : public CanMakeCheckedPtr<RenderStyle> {
     void setFontWeight(FontSelectionValue);
     void setFontStretch(FontSelectionValue);
     void setFontItalic(std::optional<FontSelectionValue>);
-    void setFontPalette(FontPalette);
+    void setFontPalette(const FontPalette&);
 
     void setColor(const Color&);
     inline void setTextIndent(Length&&);

Source/WebCore/rendering/style/RenderStyleInlines.h

@@ -214,7 +214,7 @@ inline float RenderStyle::flexGrow() const { return m_nonInheritedData->miscData
 inline float RenderStyle::flexShrink() const { return m_nonInheritedData->miscData->flexibleBox->flexShrink; }
 inline FlexWrap RenderStyle::flexWrap() const { return static_cast<FlexWrap>(m_nonInheritedData->miscData->flexibleBox->flexWrap); }
 inline std::optional<FontSelectionValue> RenderStyle::fontItalic() const { return fontDescription().italic(); }
-inline FontPalette RenderStyle::fontPalette() const { return fontDescription().fontPalette(); }
+inline const FontPalette& RenderStyle::fontPalette() const { return fontDescription().fontPalette(); }
 inline FontSizeAdjust RenderStyle::fontSizeAdjust() const { return fontDescription().fontSizeAdjust(); }
 inline FontSelectionValue RenderStyle::fontStretch() const { return fontDescription().stretch(); }
 inline FontVariationSettings RenderStyle::fontVariationSettings() const { return fontDescription().variationSettings(); }

Source/WebCore/style/StyleBuilderCustom.h

@@ -1635,9 +1635,9 @@ inline void BuilderCustom::applyInitialFontVariantAlternates(BuilderState& build
 
 inline void BuilderCustom::applyValueFontVariantAlternates(BuilderState& builderState, CSSValue& value)
 {
-    auto setAlternates = [&builderState](FontVariantAlternates alternates) {
+    auto setAlternates = [&builderState](const FontVariantAlternates& alternates) {
         auto fontDescription = builderState.fontDescription();
-        fontDescription.setVariantAlternates(WTFMove(alternates));
+        fontDescription.setVariantAlternates(alternates);
         builderState.setFontDescription(WTFMove(fontDescription));
     };
 
@@ -1649,7 +1649,7 @@ inline void BuilderCustom::applyValueFontVariantAlternates(BuilderState& builder
         if (primitiveValue->valueID() == CSSValueHistoricalForms) {
             auto alternates = FontVariantAlternates::Normal();
             alternates.valuesRef().historicalForms = true;
-            setAlternates(WTFMove(alternates));
+            setAlternates(alternates);
             return;
         }
         return;