commit cfc607cf57d453f977c9c4bf09b41ac481c4bbec
author Seigo Nonaka <nona@google.com> Wed Dec 02 10:53:18 2015 +0900
committer Seigo Nonaka <nona@google.com> Mon Dec 07 16:50:20 2015 -0800
tree 8c77b689bdeef7721a7248955c306dfe1907c90e
parent 39a275b3980b5ea75e060da540229b95a47333f7

Introduce cache mechanism for LocaleList.

Setting the LocaleList to the native Paint object is not a lightweight
operation since it needs to propagate a string object to the native code
which then needs to parse it for making minikin language list.

To avoid performance regressions, cache the minikin language ID in
android.graphics.Paint and send the LocaleList with cached ID
instead of a string the next time native code is called.

BUG: 25122318
Change-Id: Ib5ce8bcff8a1c0a2b1a1c3d1868ea8be5a0e642f

core/jni/android/graphics/Paint.cpp

diff --git a/core/jni/android/graphics/Paint.cpp b/core/jni/android/graphics/Paint.cpp
index 9c11dd1..654d148 100644
--- a/core/jni/android/graphics/Paint.cpp
+++ b/core/jni/android/graphics/Paint.cpp
@@ -71,13 +71,6 @@
     paint->setTextEncoding(Paint::kGlyphID_TextEncoding);
 }
 
-struct LocalesCacheEntry {
-    std::string javaLocales;
-    std::string languageTags;
-};
-
-static thread_local LocalesCacheEntry sSingleEntryLocalesCache;
-
 namespace PaintGlue {
     enum MoveOpt {
         AFTER, AT_OR_AFTER, BEFORE, AT_OR_BEFORE, AT
@@ -402,15 +395,20 @@
         }
     }
 
-    static void setTextLocales(JNIEnv* env, jobject clazz, jlong objHandle, jstring locales) {
+    static jint setTextLocales(JNIEnv* env, jobject clazz, jlong objHandle, jstring locales) {
         Paint* obj = reinterpret_cast<Paint*>(objHandle);
         ScopedUtfChars localesChars(env, locales);
-        if (sSingleEntryLocalesCache.javaLocales != localesChars.c_str()) {
-            sSingleEntryLocalesCache.javaLocales = localesChars.c_str();
-            toLanguageTags(&sSingleEntryLocalesCache.languageTags, localesChars.c_str());
-        }
+        std::string buf;
+        toLanguageTags(&buf, localesChars.c_str());
+        jint minikinLangListId = FontStyle::registerLanguageList(buf);
+        obj->setMinikinLangListId(minikinLangListId);
+        return minikinLangListId;
+    }
 
-        obj->setTextLocales(sSingleEntryLocalesCache.languageTags);
+    static void setTextLocalesByMinikinLangListId(JNIEnv* env, jobject clazz, jlong objHandle,
+            jint minikinLangListId) {
+        Paint* obj = reinterpret_cast<Paint*>(objHandle);
+        obj->setMinikinLangListId(minikinLangListId);
     }
 
     static jboolean isElegantTextHeight(JNIEnv* env, jobject, jlong paintHandle) {
@@ -991,7 +989,9 @@
     {"nSetRasterizer","!(JJ)J", (void*) PaintGlue::setRasterizer},
     {"nGetTextAlign","!(J)I", (void*) PaintGlue::getTextAlign},
     {"nSetTextAlign","!(JI)V", (void*) PaintGlue::setTextAlign},
-    {"nSetTextLocales","!(JLjava/lang/String;)V", (void*) PaintGlue::setTextLocales},
+    {"nSetTextLocales","!(JLjava/lang/String;)I", (void*) PaintGlue::setTextLocales},
+    {"nSetTextLocalesByMinikinLangListId","!(JI)V",
+            (void*) PaintGlue::setTextLocalesByMinikinLangListId},
     {"nIsElegantTextHeight","!(J)Z", (void*) PaintGlue::isElegantTextHeight},
     {"nSetElegantTextHeight","!(JZ)V", (void*) PaintGlue::setElegantTextHeight},
     {"nGetTextSize","!(J)F", (void*) PaintGlue::getTextSize},