Add missing primitives for reading/writing float and double

Author: eregon

src/main/java/org/truffleruby/extra/ffi/Pointer.java

@@ -80,6 +80,16 @@ public void writeLong(long offset, long value) {
         UNSAFE.putLong(address + offset, value);
     }
 
+    public void writeFloat(long offset, float value) {
+        assert address + offset != 0;
+        UNSAFE.putFloat(address + offset, value);
+    }
+
+    public void writeDouble(long offset, double value) {
+        assert address + offset != 0;
+        UNSAFE.putDouble(address + offset, value);
+    }
+
     public void writePointer(long offset, Pointer value) {
         writeLong(offset, value.getAddress());
     }
@@ -147,6 +157,11 @@ public long readLong(long offset) {
         return UNSAFE.getLong(address + offset);
     }
 
+    public float readFloat(long offset) {
+        assert address + offset != 0;
+        return UNSAFE.getFloat(address + offset);
+    }
+
     public double readDouble(long offset) {
         assert address + offset != 0;
         return UNSAFE.getDouble(address + offset);

src/main/java/org/truffleruby/extra/ffi/PointerNodes.java

@@ -429,8 +429,20 @@ private static Object readUnsignedLong(RubyContext context, Pointer ptr, int off
 
     }
 
+    @Primitive(name = "pointer_read_float")
+    public static abstract class PointerReadFloatNode extends PointerPrimitiveArrayArgumentsNode {
+
+        @Specialization
+        public double readFloat(long address) {
+            final Pointer ptr = new Pointer(address);
+            checkNull(ptr);
+            return ptr.readFloat(0);
+        }
+
+    }
+
     @Primitive(name = "pointer_read_double")
-    public static abstract class PointerReadDoublePrimitiveNode extends PointerPrimitiveArrayArgumentsNode {
+    public static abstract class PointerReadDoubleNode extends PointerPrimitiveArrayArgumentsNode {
 
         @Specialization
         public double readDouble(long address) {
@@ -843,6 +855,32 @@ private static void writeUnsignedLong(Pointer ptr, int offset, DynamicObject val
 
     }
 
+    @Primitive(name = "pointer_write_float")
+    public static abstract class PointerWriteFloatNode extends PointerPrimitiveArrayArgumentsNode {
+
+        @Specialization
+        public DynamicObject writeFloat(long address, double value) {
+            final Pointer ptr = new Pointer(address);
+            checkNull(ptr);
+            ptr.writeFloat(0, (float) value);
+            return nil();
+        }
+
+    }
+
+    @Primitive(name = "pointer_write_double")
+    public static abstract class PointerWriteDoubleNode extends PointerPrimitiveArrayArgumentsNode {
+
+        @Specialization
+        public DynamicObject writeDouble(long address, double value) {
+            final Pointer ptr = new Pointer(address);
+            checkNull(ptr);
+            ptr.writeDouble(0, value);
+            return nil();
+        }
+
+    }
+
     @Primitive(name = "pointer_write_pointer", lowerFixnum = 2)
     public static abstract class PointerWritePointerPrimitiveNode extends PointerPrimitiveArrayArgumentsNode {