Remove unnecessary shifts in gcd() (#12480)

findepi · web-flow · commit a08f923c2acb · 2024-09-16T21:04:51.000+02:00
The `a` and `b` are shifted as a next instruction.
diff --git a/datafusion/functions/src/math/gcd.rs b/datafusion/functions/src/math/gcd.rs
@@ -102,8 +102,6 @@ pub(super) fn unsigned_gcd(mut a: u64, mut b: u64) -> u64 {
     }
 
     let shift = (a | b).trailing_zeros();
-    a >>= shift;
-    b >>= shift;
     a >>= a.trailing_zeros();
     loop {
         b >>= b.trailing_zeros();

Original file line number	Diff line number	Diff line change
`@@ -102,8 +102,6 @@ pub(super) fn unsigned_gcd(mut a: u64, mut b: u64) -> u64 {`
`102`	`102`	`}`
`103`	`103`
`104`	`104`	`let shift = (a \| b).trailing_zeros();`
`105`		`- a >>= shift;`
`106`		`- b >>= shift;`
`107`	`105`	`a >>= a.trailing_zeros();`
`108`	`106`	`loop {`
`109`	`107`	`b >>= b.trailing_zeros();`