Use wrapping integer ops

ebfe · Apr 23, 2015 · 3f50f81 · 3f50f81
1 parent 3bafbe2
commit 3f50f81
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Showing 2 changed files with 8 additions and 8 deletions.
diff --git a/src/blake2b.rs b/src/blake2b.rs
@@ -167,13 +167,13 @@ impl Blake2b {
 
         macro_rules! g(
             ($r: expr, $i: expr, $a: expr, $b: expr, $c: expr, $d: expr) => ({
-                $a = $a + $b + m[SIGMA[$r][2*$i+0] as usize];
+                $a = $a.wrapping_add($b).wrapping_add(m[SIGMA[$r][2*$i+0] as usize]);
                 $d = ($d ^ $a).rotate_right(32);
-                $c = $c + $d;
+                $c = $c.wrapping_add($d);
                 $b = ($b ^ $c).rotate_right(24);
-                $a = $a + $b + m[SIGMA[$r][2*$i+1] as usize];
+                $a = $a.wrapping_add($b).wrapping_add(m[SIGMA[$r][2*$i+1] as usize]);
                 $d = ($d ^ $a).rotate_right(16);
-                $c = $c + $d;
+                $c = $c.wrapping_add($d);
                 $b = ($b ^ $c).rotate_right(63);
             });
         );

diff --git a/src/blake2s.rs b/src/blake2s.rs
@@ -164,13 +164,13 @@ impl Blake2s {
 
         macro_rules! g(
             ($r: expr, $i: expr, $a: expr, $b: expr, $c: expr, $d: expr) => ({
-                $a = $a + $b + m[SIGMA[$r][2*$i+0] as usize];
+                $a = $a.wrapping_add($b).wrapping_add(m[SIGMA[$r][2*$i+0] as usize]);
                 $d = ($d ^ $a).rotate_right(16);
-                $c = $c + $d;
+                $c = $c.wrapping_add($d);
                 $b = ($b ^ $c).rotate_right(12);
-                $a = $a + $b + m[SIGMA[$r][2*$i+1] as usize];
+                $a = $a.wrapping_add($b).wrapping_add(m[SIGMA[$r][2*$i+1] as usize]);
                 $d = ($d ^ $a).rotate_right(8);
-                $c = $c + $d;
+                $c = $c.wrapping_add($d);
                 $b = ($b ^ $c).rotate_right(7);
             });
         );