Add bit ranking function in Java

5 files changed, 28 insertions, 3 deletions

diff --git a/searchlib/abi-spec.json b/searchlib/abi-spec.json
index 5035a5f583f..65151dd6ff0 100644
--- a/searchlib/abi-spec.json
+++ b/searchlib/abi-spec.json
@@ -1033,6 +1033,7 @@
       "public static final int FMOD",
       "public static final int LDEXP",
       "public static final int POW",
+      "public static final int BIT",
       "public static final int MAP",
       "public static final int REDUCE",
       "public static final int JOIN",
@@ -1387,7 +1388,8 @@
       "public static final enum com.yahoo.searchlib.rankingexpression.rule.Function ldexp",
       "public static final enum com.yahoo.searchlib.rankingexpression.rule.Function max",
       "public static final enum com.yahoo.searchlib.rankingexpression.rule.Function min",
-      "public static final enum com.yahoo.searchlib.rankingexpression.rule.Function pow"
+      "public static final enum com.yahoo.searchlib.rankingexpression.rule.Function pow",
+      "public static final enum com.yahoo.searchlib.rankingexpression.rule.Function bit"
     ]
   },
   "com.yahoo.searchlib.rankingexpression.rule.FunctionNode": {
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java
index b109e6503e3..e41732f9d16 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java
@@ -156,6 +156,7 @@ public class TensorValue extends Value {
             case pow: return value.pow(argument);
             case fmod: return value.fmod(argument);
             case ldexp: return value.ldexp(argument);
+            case bit: return value.bit(argument);
             default: throw new UnsupportedOperationException("Cannot combine two tensors using " + function);
         }
     }
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java
index 99afb3b38d0..ad04832053f 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java
@@ -1,6 +1,7 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.searchlib.rankingexpression.rule;
 
+import com.yahoo.tensor.Tensor;
 import com.yahoo.tensor.functions.ScalarFunctions;
 
 import java.io.Serializable;
@@ -45,7 +46,8 @@ public enum Function implements Serializable {
     ldexp(2)  { public double evaluate(double x, double y) { return x*pow(2,(int)y); } },
     max(2)    { public double evaluate(double x, double y) { return max(x,y); } },
     min(2)    { public double evaluate(double x, double y) { return min(x,y); } },
-    pow(2)    { public double evaluate(double x, double y) { return pow(x,y); } };
+    pow(2)    { public double evaluate(double x, double y) { return pow(x,y); } },
+    bit(2)    { public double evaluate(double x, double y) { return ((int)y < 8 && (int)y >= 8 && ((int)x & (1 << (int)y)) != 0) ? 1.0 : 0.0; } };
 
     private final int arity;
 
diff --git a/searchlib/src/main/javacc/RankingExpressionParser.jj b/searchlib/src/main/javacc/RankingExpressionParser.jj
index 7506fe250fc..99eff010628 100755
--- a/searchlib/src/main/javacc/RankingExpressionParser.jj
+++ b/searchlib/src/main/javacc/RankingExpressionParser.jj
@@ -123,6 +123,7 @@ TOKEN :
     // MAX
     // MIN
     <POW: "pow"> |
+    <BIT: "bit"> |
 
     <MAP: "map"> |
     <REDUCE: "reduce"> |
@@ -733,7 +734,8 @@ Function binaryFunctionName() : { }
     <LDEXP> { return Function.ldexp; } |
     <MAX>   { return Function.max;   } |
     <MIN>   { return Function.min;   } |
-    <POW>   { return Function.pow;   }
+    <POW>   { return Function.pow;   } |
+    <BIT>   { return Function.bit;   }
 }
 
 List<ExpressionNode> expressionList() :
diff --git a/searchlib/src/test/java/com/yahoo/searchlib/rankingexpression/evaluation/EvaluationTestCase.java b/searchlib/src/test/java/com/yahoo/searchlib/rankingexpression/evaluation/EvaluationTestCase.java
index d6302d7026e..4a3c4b248be 100644
--- a/searchlib/src/test/java/com/yahoo/searchlib/rankingexpression/evaluation/EvaluationTestCase.java
+++ b/searchlib/src/test/java/com/yahoo/searchlib/rankingexpression/evaluation/EvaluationTestCase.java
@@ -403,6 +403,24 @@ public class EvaluationTestCase {
     }
 
     @Test
+    public void testBitExtraction() {
+        EvaluationTester tester = new EvaluationTester();
+        tester.assertEvaluates(1.0, "bit(-43,7)");
+        tester.assertEvaluates(1.0, "bit(-43,6)");
+        tester.assertEvaluates(0.0, "bit(-43,5)");
+        tester.assertEvaluates(1.0, "bit(-43,4)");
+        tester.assertEvaluates(0.0, "bit(-43,3)");
+        tester.assertEvaluates(1.0, "bit(-43,2)");
+        tester.assertEvaluates(0.0, "bit(-43,1)");
+        tester.assertEvaluates(1.0, "bit(-43,0)");
+        tester.assertEvaluates(
+                "tensor<int8>(x[40]):[1,1,0,1,0,1,0,1, 0,0,0,0,0,0,0,0, 0,1,0,1,0,1,0,1, 0,1,1,1,1,1,1,1, 1,0,0,0,0,0,0,0]",
+                "tensor<int8>(x[40])(bit(tensor0{y:x / 8}, 7 - x % 8))",
+                "tensor<int8>(y[5]):[-43,0,85,127,-128]"
+        );
+    }
+
+    @Test
     public void testCellTypeCasting() {
         EvaluationTester tester = new EvaluationTester();