sample-code: Expand the capabilities of the sample code

sample-code/math.cl

@@ -0,0 +1,36 @@
+//! Useful math functions
+
+pub fn max(a: T, b: T) -> T {
+    (if a < b { b } else { a })
+}
+
+pub fn min(a: T, b: T) -> T {
+    (if a > b { b } else { a })
+}
+
+pub fn count_leading_zeroes(n: u64) -> u64 {
+    let mut xd = 64;
+    if n < 0 {
+        return 0;
+    }
+    while n != 0 {
+        xd -= 1;
+        n >>= 1;
+    }
+    xd
+}
+
+pub fn count_trailing_zeroes(n: u64) -> u64 {
+    let mut xd = 0;
+    if n == 0 {
+        64
+    } else if n < 0 {
+        0
+    } else {
+        while n & 1 == 0 {
+            xd += 1;
+            n >>= 1;
+        }
+        xd
+    }
+}