Improve ellipsize performance

Instead of iterate all ellipsized characters, only iterate the necessary
ranges for copying.

Bug: 188913943
Test: atest CtsTextTestCases CtsGraphicsTestCases CtsWidgetTestCases
Change-Id: I3d03b1e3897e427c23fbe51315f412c57a4ce9e9
Merged-In: I3d03b1e3897e427c23fbe51315f412c57a4ce9e9
(cherry picked from commit ae1912b62f7dfa361acfbe472cb8a49cd60f746e)

1 files changed, 7 insertions, 7 deletions

diff --git a/core/java/android/text/Layout.java b/core/java/android/text/Layout.java
index 8f9233f06839..38240fa7e9d9 100644
--- a/core/java/android/text/Layout.java
+++ b/core/java/android/text/Layout.java
@@ -2214,20 +2214,20 @@ public abstract class Layout {
         int ellipsisStart = getEllipsisStart(line);
         int linestart = getLineStart(line);
 
-        for (int i = ellipsisStart; i < ellipsisStart + ellipsisCount; i++) {
+        final int min = Math.max(0, start - ellipsisStart - linestart);
+        final int max = Math.min(ellipsisCount, end - ellipsisStart - linestart);
+
+        for (int i = min; i < max; i++) {
             char c;
 
-            if (i == ellipsisStart) {
+            if (i == 0) {
                 c = getEllipsisChar(method); // ellipsis
             } else {
                 c = '\uFEFF'; // 0-width space
             }
 
-            int a = i + linestart;
-
-            if (a >= start && a < end) {
-                dest[destoff + a - start] = c;
-            }
+            int a = i + ellipsisStart + linestart;
+            dest[destoff + a - start] = c;
         }
     }