diff --git a/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/Combine.java b/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/Combine.java
index de82635b87aae2c50b183ba46e1af4fb70496d4c..cb7f5769968f1f4536626ac80c916e4546a9de3d 100644
--- a/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/Combine.java
+++ b/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/Combine.java
@@ -582,11 +582,11 @@ public abstract class Combine extends RBuiltinNode {
         return current;
     }
 
-    public boolean hasArgNames() {
+    protected boolean hasArgNames() {
         return getSuppliedArgsNames() != null;
     }
 
-    public boolean noArgNames() {
+    protected boolean noArgNames() {
         return !hasArgNames();
     }
 }
diff --git a/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/PrettyPrinterNode.java b/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/PrettyPrinterNode.java
index 4a52829723d6b6f6e72138d38fe93b56d9c08b72..8576637c1bbc7f465c80d774f2e8e03e43c59878 100644
--- a/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/PrettyPrinterNode.java
+++ b/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/PrettyPrinterNode.java
@@ -1540,15 +1540,15 @@ public abstract class PrettyPrinterNode extends RNode {
             return builderToString(b);
         }
 
-        public boolean isEmpty(RAbstractVector vector, RIntVector dimensions, int offset, byte isListOrStringVector, byte isComplexOrRawVector) {
+        protected boolean isEmpty(RAbstractVector vector, RIntVector dimensions, int offset, byte isListOrStringVector, byte isComplexOrRawVector) {
             return vector.getLength() == 0;
         }
 
-        public boolean isEmpty(RAbstractDoubleVector vector, RIntVector dimensions, int offset, byte isListOrStringVector, byte isComplexOrRawVector) {
+        protected boolean isEmpty(RAbstractDoubleVector vector, RIntVector dimensions, int offset, byte isListOrStringVector, byte isComplexOrRawVector) {
             return vector.getLength() == 0;
         }
 
-        public boolean isEmpty(RAbstractComplexVector vector, RIntVector dimensions, int offset, byte isListOrStringVector, byte isComplexOrRawVector) {
+        protected boolean isEmpty(RAbstractComplexVector vector, RIntVector dimensions, int offset, byte isListOrStringVector, byte isComplexOrRawVector) {
             return vector.getLength() == 0;
         }
 
diff --git a/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/UpdateDiag.java b/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/UpdateDiag.java
index a3833acc9aafa23106a841f42e9cd2510248060d..30fcd1f4e9f13f8132e67f4d5097d4b9319f81f5 100644
--- a/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/UpdateDiag.java
+++ b/com.oracle.truffle.r.nodes.builtin/src/com/oracle/truffle/r/nodes/builtin/base/UpdateDiag.java
@@ -43,21 +43,21 @@ public abstract class UpdateDiag extends RInvisibleBuiltinNode {
 
     @Child protected CastDoubleNode castDouble;
 
-    public static boolean isMatrix(RAbstractVector vector) {
+    protected static boolean isMatrix(RAbstractVector vector) {
         return vector.hasDimensions() && vector.getDimensions().length == 2;
     }
 
     // FIXME The following two are workarounds for a Truffle-DSL bug.
 
-    public static boolean isMatrix(RAbstractIntVector vector) {
+    protected static boolean isMatrix(RAbstractIntVector vector) {
         return isMatrix((RAbstractVector) vector);
     }
 
-    public static boolean isMatrix(RAbstractDoubleVector vector) {
+    protected static boolean isMatrix(RAbstractDoubleVector vector) {
         return isMatrix((RAbstractVector) vector);
     }
 
-    public static boolean correctReplacementLength(RAbstractVector matrix, RAbstractVector replacement) {
+    protected static boolean correctReplacementLength(RAbstractVector matrix, RAbstractVector replacement) {
         return replacement.getLength() == 1 || Math.min(matrix.getDimensions()[0], matrix.getDimensions()[1]) == replacement.getLength();
     }
 
diff --git a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/ArrayPositionCast.java b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/ArrayPositionCast.java
index 3789639e66c7e2425b6e96208564b1a927a529c7..23e1f6952543179779b379e7eed8715968b494b8 100644
--- a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/ArrayPositionCast.java
+++ b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/ArrayPositionCast.java
@@ -169,7 +169,7 @@ public abstract class ArrayPositionCast extends RNode {
         return 0;
     }
 
-    public static boolean sizeOneOp(Object op, RAbstractContainer container, RAbstractIntVector operand) {
+    protected static boolean sizeOneOp(Object op, RAbstractContainer container, RAbstractIntVector operand) {
         return operand.getLength() == 1;
     }
 
diff --git a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/VectorPositionCast.java b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/VectorPositionCast.java
index dd5b34d8ef45cece061a26866090c00acd576ad8..899f4559329d615a26600f838dc7b933388dd682 100644
--- a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/VectorPositionCast.java
+++ b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/access/VectorPositionCast.java
@@ -79,11 +79,11 @@ public abstract class VectorPositionCast extends RNode {
         return ((int) stride == stride) && start >= 1.0;
     }
 
-    public static boolean greaterEqualOneSequence(RIntSequence operand) {
+    protected static boolean greaterEqualOneSequence(RIntSequence operand) {
         return operand.getStart() >= 1 && (operand.getStride() > 0 || operand.getEnd() > 0);
     }
 
-    public static boolean startingZeroSequence(RIntSequence operand) {
+    protected static boolean startingZeroSequence(RIntSequence operand) {
         return operand.getStart() == 0 && operand.getStride() > 0;
     }
 
diff --git a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryArithmeticNode.java b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryArithmeticNode.java
index b5b92db21289df6cab9064d8a48517e958b5acdb..3f2c20c73ab3bcacd48a1eac8b3250f05cdf62c0 100644
--- a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryArithmeticNode.java
+++ b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryArithmeticNode.java
@@ -157,7 +157,7 @@ public abstract class BinaryArithmeticNode extends BinaryNode {
         throw RError.error(frame, this.getSourceSection(), RError.Message.NON_NUMERIC_BINARY);
     }
 
-    public boolean supportsIntResult() {
+    protected boolean supportsIntResult() {
         return arithmetic.isSupportsIntResult();
     }
 
diff --git a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNode.java b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNode.java
index 6dd3496272786a03aa342c2d304ef86073cf9688..fceb1f7ef747c5b984b967c39585e78216ef4891 100644
--- a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNode.java
+++ b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNode.java
@@ -1141,51 +1141,51 @@ public abstract class BinaryBooleanNode extends BinaryNode {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumericVector(RRaw left, RAbstractVector right) {
+    protected boolean convertRawToNumericVector(RRaw left, RAbstractVector right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumericVector(RAbstractVector left, RRaw right) {
+    protected boolean convertRawToNumericVector(RAbstractVector left, RRaw right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumericVector(RRawVector left, RAbstractVector right) {
+    protected boolean convertRawToNumericVector(RRawVector left, RAbstractVector right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumericVector(RAbstractVector left, RRawVector right) {
+    protected boolean convertRawToNumericVector(RAbstractVector left, RRawVector right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumeric(RRaw left, RRaw right) {
+    protected boolean convertRawToNumeric(RRaw left, RRaw right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumeric(RRawVector left, RRawVector right) {
+    protected boolean convertRawToNumeric(RRawVector left, RRawVector right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumeric(RRaw left, RRawVector right) {
+    protected boolean convertRawToNumeric(RRaw left, RRawVector right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean convertRawToNumeric(RRawVector left, RRaw right) {
+    protected boolean convertRawToNumeric(RRawVector left, RRaw right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean expectLogical(RRaw left, RRaw right) {
+    protected boolean expectLogical(RRaw left, RRaw right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean expectLogical(RRawVector left, RRawVector right) {
+    protected boolean expectLogical(RRawVector left, RRawVector right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean expectLogical(RRawVector left, RRaw right) {
+    protected boolean expectLogical(RRawVector left, RRaw right) {
         return isVectorizedLogicalOp();
     }
 
-    public boolean expectLogical(RRaw left, RRawVector right) {
+    protected boolean expectLogical(RRaw left, RRawVector right) {
         return isVectorizedLogicalOp();
     }
 
diff --git a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNonVectorizedNode.java b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNonVectorizedNode.java
index 1a8e6dd1e7542046f06c7ea316dcd34b9d0532f8..928d14b60b41e0433e5b6ebd9a23470b572f24ed 100644
--- a/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNonVectorizedNode.java
+++ b/com.oracle.truffle.r.nodes/src/com/oracle/truffle/r/nodes/binary/BinaryBooleanNonVectorizedNode.java
@@ -66,7 +66,7 @@ public abstract class BinaryBooleanNonVectorizedNode extends BinaryNode {
     }
 
     @ShortCircuit("arguments[1]")
-    public boolean needsRightOperand(Object leftValue) {
+    protected boolean needsRightOperand(Object leftValue) {
         return logic.requiresRightOperand(RTypesGen.RTYPES.asByte(leftValue));
     }
 
@@ -230,11 +230,11 @@ public abstract class BinaryBooleanNonVectorizedNode extends BinaryNode {
         return left;
     }
 
-    boolean isZeroLength(byte left, boolean needsRightOperand, RAbstractVector operand) {
+    protected boolean isZeroLength(byte left, boolean needsRightOperand, RAbstractVector operand) {
         return operand.getLength() == 0;
     }
 
-    boolean isZeroLength(Object left, boolean needsRightOperand, RAbstractVector operand) {
+    protected boolean isZeroLength(Object left, boolean needsRightOperand, RAbstractVector operand) {
         return operand.getLength() == 0;
     }
 
@@ -320,15 +320,15 @@ public abstract class BinaryBooleanNonVectorizedNode extends BinaryNode {
             return RRuntime.int2logical(operand.getDataAt(0));
         }
 
-        boolean isZeroLength(RAbstractVector operand) {
+        protected boolean isZeroLength(RAbstractVector operand) {
             return operand.getLength() == 0;
         }
 
-        boolean isStringVector(RAbstractVector vector) {
+        protected boolean isStringVector(RAbstractVector vector) {
             return vector.getElementClass() == RString.class;
         }
 
-        boolean isRawVector(RAbstractVector vector) {
+        protected boolean isRawVector(RAbstractVector vector) {
             return vector.getElementClass() == RRaw.class;
         }
     }