Remove unuseful optimization in RKISS

[stockfish] / src / rkiss.h

diff --git a/src/rkiss.h b/src/rkiss.h
index 18c1d4f69dacc8480b0894ae9de1829e5ef6a772..ffcaf35a4752db1112c49841bfbf9cdaeba75cd8 100644 (file)
--- a/src/rkiss.h
+++ b/src/rkiss.h
@@ -43,7 +43,7 @@
 
 class RKISS {
 
-  struct S { uint64_t a, b, c, d; } s; // Keep variables always together
+  uint64_t a, b, c, d;
 
   uint64_t rotate(uint64_t x, uint64_t k) const {
     return (x << k) | (x >> (64 - k));
@@ -51,19 +51,18 @@ class RKISS {
 
   uint64_t rand64() {
 
-    const uint64_t
-      e = s.a - rotate(s.b,  7);
-    s.a = s.b ^ rotate(s.c, 13);
-    s.b = s.c + rotate(s.d, 37);
-    s.c = s.d + e;
-    return s.d = e + s.a;
+    const uint64_t e = a - rotate(b,  7);
+    a = b ^ rotate(c, 13);
+    b = c + rotate(d, 37);
+    c = d + e;
+    return d = e + a;
   }
 
 public:
   RKISS(int seed = 73) {
 
-    s.a = 0xf1ea5eed;
-    s.b = s.c = s.d = 0xd4e12c77;
+    a = 0xF1EA5EED, b = c = d = 0xD4E12C77;
+
     for (int i = 0; i < seed; ++i) // Scramble a few rounds
         rand64();
   }