Benchmark rework to better reflect real usage and slight performance improvements.

Change-Id: I3979c725ff9058fc208626ffb5fce95c2e03ac19

engine/src/flutter/benchmarks/paragraph_benchmarks.cc

@@ -44,14 +44,14 @@ static void BM_ParagraphShortLayout(benchmark::State& state) {
   txt::TextStyle text_style;
   text_style.color = SK_ColorBLACK;
   auto font_collection = FontCollection::GetFontCollection(txt::GetFontDir());
+  txt::ParagraphBuilder builder(paragraph_style, &font_collection);
+
+  builder.PushStyle(text_style);
+  builder.AddText(u16_text);
+  builder.Pop();
+  auto paragraph = builder.Build();
   while (state.KeepRunning()) {
-    txt::ParagraphBuilder builder(paragraph_style, &font_collection);
-
-    builder.PushStyle(text_style);
-    builder.AddText(u16_text);
-    builder.Pop();
-    auto paragraph = builder.Build();
-
+    paragraph->SetDirty();
     paragraph->Layout(300, true);
   }
 }
@@ -85,14 +85,14 @@ static void BM_ParagraphLongLayout(benchmark::State& state) {
   txt::TextStyle text_style;
   text_style.color = SK_ColorBLACK;
   auto font_collection = FontCollection::GetFontCollection(txt::GetFontDir());
+  txt::ParagraphBuilder builder(paragraph_style, &font_collection);
+
+  builder.PushStyle(text_style);
+  builder.AddText(u16_text);
+  builder.Pop();
+  auto paragraph = builder.Build();
   while (state.KeepRunning()) {
-    txt::ParagraphBuilder builder(paragraph_style, &font_collection);
-
-    builder.PushStyle(text_style);
-    builder.AddText(u16_text);
-    builder.Pop();
-    auto paragraph = builder.Build();
-
+    paragraph->SetDirty();
     paragraph->Layout(300, true);
   }
 }
@@ -127,14 +127,14 @@ static void BM_ParagraphJustifyLayout(benchmark::State& state) {
   txt::TextStyle text_style;
   text_style.color = SK_ColorBLACK;
   auto font_collection = FontCollection::GetFontCollection(txt::GetFontDir());
+  txt::ParagraphBuilder builder(paragraph_style, &font_collection);
+
+  builder.PushStyle(text_style);
+  builder.AddText(u16_text);
+  builder.Pop();
+  auto paragraph = builder.Build();
   while (state.KeepRunning()) {
-    txt::ParagraphBuilder builder(paragraph_style, &font_collection);
-
-    builder.PushStyle(text_style);
-    builder.AddText(u16_text);
-    builder.Pop();
-    auto paragraph = builder.Build();
-
+    paragraph->SetDirty();
     paragraph->Layout(300, true);
   }
 }
@@ -151,48 +151,51 @@ static void BM_ParagraphManyStylesLayout(benchmark::State& state) {
   txt::TextStyle text_style;
   text_style.color = SK_ColorBLACK;
   auto font_collection = FontCollection::GetFontCollection(txt::GetFontDir());
+  txt::ParagraphBuilder builder(paragraph_style, &font_collection);
+  for (int i = 0; i < 1000; ++i) {
+    builder.PushStyle(text_style);
+    builder.AddText(u16_text);
+  }
+  auto paragraph = builder.Build();
   while (state.KeepRunning()) {
-    txt::ParagraphBuilder builder(paragraph_style, &font_collection);
-    for (int i = 0; i < 1000; ++i) {
-      builder.PushStyle(text_style);
-      builder.AddText(u16_text);
-    }
-    auto paragraph = builder.Build();
+    paragraph->SetDirty();
     paragraph->Layout(300, true);
   }
 }
 BENCHMARK(BM_ParagraphManyStylesLayout);
 
 static void BM_ParagraphTextBigO(benchmark::State& state) {
-  std::string text(state.range(0), '-');
-  auto icu_text = icu::UnicodeString::fromUTF8(text);
-  std::u16string u16_text(icu_text.getBuffer(),
-                          icu_text.getBuffer() + icu_text.length());
+  std::vector<uint16_t> text;
+  for (uint16_t i = 0; i < state.range(0); ++i) {
+    text.push_back(i % 5 == 0 ? ' ' : i);
+  }
+  std::u16string u16_text(text.data(), text.data() + text.size());
 
   txt::ParagraphStyle paragraph_style;
 
   txt::TextStyle text_style;
   text_style.color = SK_ColorBLACK;
   auto font_collection = FontCollection::GetFontCollection(txt::GetFontDir());
+
+  txt::ParagraphBuilder builder(paragraph_style, &font_collection);
+
+  builder.PushStyle(text_style);
+  builder.AddText(u16_text);
+  builder.Pop();
+  auto paragraph = builder.Build();
   while (state.KeepRunning()) {
-    txt::ParagraphBuilder builder(paragraph_style, &font_collection);
-
-    builder.PushStyle(text_style);
-    builder.AddText(u16_text);
-    builder.Pop();
-    auto paragraph = builder.Build();
-
+    paragraph->SetDirty();
     paragraph->Layout(300, true);
   }
   state.SetComplexityN(state.range(0));
 }
 BENCHMARK(BM_ParagraphTextBigO)
-    ->RangeMultiplier(10)
+    ->RangeMultiplier(4)
     ->Range(1 << 6, 1 << 14)
-    ->Complexity(benchmark::oNSquared);
+    ->Complexity(benchmark::oN);
 
 static void BM_ParagraphStylesBigO(benchmark::State& state) {
-  const char* text = "A short sentence. ";
+  const char* text = "vry shrt ";
   auto icu_text = icu::UnicodeString::fromUTF8(text);
   std::u16string u16_text(icu_text.getBuffer(),
                           icu_text.getBuffer() + icu_text.length());
@@ -202,22 +205,23 @@ static void BM_ParagraphStylesBigO(benchmark::State& state) {
   txt::TextStyle text_style;
   text_style.color = SK_ColorBLACK;
   auto font_collection = FontCollection::GetFontCollection(txt::GetFontDir());
-  while (state.KeepRunning()) {
-    txt::ParagraphBuilder builder(paragraph_style, &font_collection);
+  txt::ParagraphBuilder builder(paragraph_style, &font_collection);
 
-    for (int i = 0; i < state.range(0); ++i) {
-      builder.PushStyle(text_style);
-      builder.AddText(u16_text);
-    }
-    auto paragraph = builder.Build();
+  for (int i = 0; i < state.range(0); ++i) {
+    builder.PushStyle(text_style);
+    builder.AddText(u16_text);
+  }
+  auto paragraph = builder.Build();
+  while (state.KeepRunning()) {
+    paragraph->SetDirty();
     paragraph->Layout(300, true);
   }
   state.SetComplexityN(state.range(0));
 }
 BENCHMARK(BM_ParagraphStylesBigO)
-    ->RangeMultiplier(20)
-    ->Range(1 << 4, 1 << 12)
-    ->Complexity(benchmark::oNSquared);
+    ->RangeMultiplier(4)
+    ->Range(1 << 3, 1 << 12)
+    ->Complexity(benchmark::oN);
 
 // -----------------------------------------------------------------------------
 //
@@ -228,8 +232,8 @@ BENCHMARK(BM_ParagraphStylesBigO)
 
 static void BM_ParagraphMinikinDoLayout(benchmark::State& state) {
   std::vector<uint16_t> text;
-  for (uint16_t i = 0; i < state.range(0); ++i) {
-    text.push_back(i);
+  for (uint16_t i = 0; i < state.range(0) * 3; ++i) {
+    text.push_back(i % 5 == 0 ? ' ' : i);
   }
   minikin::FontStyle font;
   txt::TextStyle text_style;
@@ -247,13 +251,13 @@ static void BM_ParagraphMinikinDoLayout(benchmark::State& state) {
 
   while (state.KeepRunning()) {
     minikin::Layout layout;
-    layout.doLayout(text.data(), 0, 50, text.size(), 0, font, paint,
+    layout.doLayout(text.data(), 0, state.range(0), text.size(), 0, font, paint,
                     collection);
   }
   state.SetComplexityN(state.range(0));
 }
 BENCHMARK(BM_ParagraphMinikinDoLayout)
-    ->RangeMultiplier(10)
+    ->RangeMultiplier(4)
     ->Range(1 << 7, 1 << 14)
     ->Complexity(benchmark::oN);
 

engine/src/flutter/src/paragraph.cc

@@ -299,12 +299,12 @@ void Paragraph::Layout(double width, bool force) {
                                     : breaks[break_index];
       const size_t layout_end = std::min(run.end, next_break);
 
-      int bidiFlags = 0;
+      bool bidiFlags = paragraph_style_.rtl;
       layout.doLayout(text_.data(), layout_start, layout_end - layout_start,
                       text_.size(), bidiFlags, font, minikin_paint,
                       font_collection_->GetMinikinFontCollectionForFamily(
                           run.style.font_family));
-      FillWhitespaceSet(run.start, run.end,
+      FillWhitespaceSet(layout_start, layout_end,
                         minikin::getHbFontLocked(layout.getFont(0)));
 
       const size_t glyph_count = layout.nGlyphs();
@@ -848,4 +848,8 @@ bool Paragraph::DidExceedMaxLines() const {
   return false;
 }
 
+void Paragraph::SetDirty(bool dirty) {
+  needs_layout_ = dirty;
+}
+
 }  // namespace txt

engine/src/flutter/src/paragraph.h

@@ -88,6 +88,11 @@ class Paragraph {
 
   bool DidExceedMaxLines() const;
 
+  // Sets the needs_layout_ to dirty. When Layout() is called, a new Layout will
+  // be performed when this is set to true. Can also be used to prevent a new
+  // Layout from being calculated by setting to false.
+  void SetDirty(bool dirty = true);
+
  private:
   friend class ParagraphBuilder;
   FRIEND_TEST(RenderTest, SimpleParagraph);