simplify rotl and rotr

zapashcanon · Feb 23, 2024 · f4027ea · f4027ea
1 parent f6e44a1
commit f4027ea
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Showing 2 changed files with 8 additions and 14 deletions.
diff --git a/src/int32.ml b/src/int32.ml
@@ -43,16 +43,13 @@ let shr_s x y = shift shift_right x y
 
 let shr_u x y = sx (shift shift_right_logical x y)
 
-(* We must mask the count to implement rotates via shifts. *)
-let clamp_rotate_count n = to_int (logand n 31l)
-
 let rotl x y =
-  let n = clamp_rotate_count y in
-  logor (shl x (of_int n)) (shr_u x (of_int (32 - n)))
+  let n = logand y 31l in
+  logor (shl x n) (shr_u x (sub 32l n))
 
 let rotr x y =
-  let n = clamp_rotate_count y in
-  logor (shr_u x (of_int n)) (shl x (of_int (32 - n)))
+  let n = logand y 31l in
+  logor (shr_u x n) (shl x (sub 32l n))
 
 let extend_s n x =
   let shift = 32 - n in

diff --git a/src/int64.ml b/src/int64.ml
@@ -68,16 +68,13 @@ let shr_s x y = shift shift_right x y
 
 let shr_u x y = shift shift_right_logical x y
 
-(* We must mask the count to implement rotates via shifts. *)
-let clamp_rotate_count n = to_int (logand n (of_int 63))
-
 let rotl x y =
-  let n = clamp_rotate_count y in
-  logor (shl x (of_int n)) (shr_u x (of_int (64 - n)))
+  let n = logand y 63L in
+  logor (shl x n) (shr_u x (sub 64L n))
 
 let rotr x y =
-  let n = clamp_rotate_count y in
-  logor (shr_u x (of_int n)) (shl x (of_int (64 - n)))
+  let n = logand y 63L in
+  logor (shr_u x n) (shl x (sub 64L n))
 
 let extend_s n x =
   let shift = 64 - n in