Add Character#digit(int, int) fastpath

Added a java fastpath for common cases in the
Character#digit(int, int) method. Improves performance
of conversions from string to numeric types.

Bug: 28008616
Change-Id: I28aacba520c3f51a5cb5a59e51d4ae593daa551c
(cherry picked from commit cff29861633f2d4907b79644dace4a6790982faf)

1 files changed, 12 insertions, 0 deletions

diff --git a/benchmarks/src/benchmarks/regression/IntegerBenchmark.java b/benchmarks/src/benchmarks/regression/IntegerBenchmark.java
index f7f97c7369..c9614d4f3d 100644
--- a/benchmarks/src/benchmarks/regression/IntegerBenchmark.java
+++ b/benchmarks/src/benchmarks/regression/IntegerBenchmark.java
@@ -133,4 +133,16 @@ public class IntegerBenchmark {
         }
         return t;
     }
+
+    public int timeIntegerValueOf(int reps) throws Exception {
+        String[] intStrings = new String[]{"0", "1", "12", "123", "1234", "12345",
+                                           "123456", "1234567", "12345678"};
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            for (int j = 0; j < intStrings.length; ++j) {
+                t += Integer.valueOf(intStrings[j]);
+            }
+        }
+        return t;
+    }
 }