RenderScript: implement a Script entry point for calling a
reduce-style kernel.

Bug: 22631253

This adds a new (currently hidden) API to the Script class and the
corresponding code for the RenderScript JNI layer.

Change-Id: I40f19aaeb90411b859bd6b0bffc3f071fa327c21
diff --git a/rs/java/android/renderscript/RenderScript.java b/rs/java/android/renderscript/RenderScript.java
index 0f4dced..326f273 100644
--- a/rs/java/android/renderscript/RenderScript.java
+++ b/rs/java/android/renderscript/RenderScript.java
@@ -31,6 +31,8 @@
 import android.os.Trace;
 import java.util.ArrayList;
 
+// TODO: Clean up the whitespace that separates methods in this class.
+
 /**
  * This class provides access to a RenderScript context, which controls RenderScript
  * initialization, resource management, and teardown. An instance of the RenderScript
@@ -727,6 +729,14 @@
         rsnScriptForEach(mContext, id, slot, ains, aout, params, limits);
     }
 
+    native void rsnScriptReduce(long con, long id, int slot, long ain,
+                                long aout, int[] limits);
+    synchronized void nScriptReduce(long id, int slot, long ain, long aout,
+                                    int[] limits) {
+        validate();
+        rsnScriptReduce(mContext, id, slot, ain, aout, limits);
+    }
+
     native void rsnScriptInvokeV(long con, long id, int slot, byte[] params);
     synchronized void nScriptInvokeV(long id, int slot, byte[] params) {
         validate();
diff --git a/rs/java/android/renderscript/Script.java b/rs/java/android/renderscript/Script.java
index 1083114..dfd0ea3 100644
--- a/rs/java/android/renderscript/Script.java
+++ b/rs/java/android/renderscript/Script.java
@@ -284,6 +284,35 @@
         mRS.nScriptForEach(getID(mRS), slot, in_ids, out_id, params, limits);
     }
 
+    /**
+     * Only intended for use by generated reflected code.
+     *
+     * @hide
+     */
+    protected void reduce(int slot, Allocation ain, Allocation aout, LaunchOptions sc) {
+        mRS.validate();
+        mRS.validateObject(ain);
+        mRS.validateObject(aout);
+
+        if (ain == null || aout == null) {
+            throw new RSIllegalArgumentException(
+                "Both ain and aout are required to be non-null.");
+        }
+
+        long in_id = ain.getID(mRS);
+        long out_id = aout.getID(mRS);
+
+        int[] limits = null;
+        if (sc != null) {
+            limits = new int[2];
+
+            limits[0] = sc.xstart;
+            limits[1] = sc.xend;
+        }
+
+        mRS.nScriptReduce(getID(mRS), slot, in_id, out_id, limits);
+    }
+
     long[] mInIdsBuffer;
 
     Script(long id, RenderScript rs) {
@@ -292,7 +321,6 @@
         mInIdsBuffer = new long[1];
     }
 
-
     /**
      * Only intended for use by generated reflected code.
      *