From 4f5116e236843492998acfa42381d14db360f2ab Mon Sep 17 00:00:00 2001 From: Tobias Decking Date: Sat, 1 Feb 2025 23:44:52 +0100 Subject: [PATCH] Use `widening_mul` --- library/core/src/fmt/num.rs | 21 +-------------------- 1 file changed, 1 insertion(+), 20 deletions(-) diff --git a/library/core/src/fmt/num.rs b/library/core/src/fmt/num.rs index 683e45b35f70a..fd548018dade3 100644 --- a/library/core/src/fmt/num.rs +++ b/library/core/src/fmt/num.rs @@ -726,28 +726,9 @@ fn udiv_1e19(n: u128) -> (u128, u64) { let quot = if n < 1 << 83 { ((n >> 19) as u64 / (DIV >> 19)) as u128 } else { - u128_mulhi(n, FACTOR) >> 62 + n.widening_mul(FACTOR).1 >> 62 }; let rem = (n - quot * DIV as u128) as u64; (quot, rem) } - -/// Multiply unsigned 128 bit integers, return upper 128 bits of the result -#[inline] -fn u128_mulhi(x: u128, y: u128) -> u128 { - let x_lo = x as u64; - let x_hi = (x >> 64) as u64; - let y_lo = y as u64; - let y_hi = (y >> 64) as u64; - - // handle possibility of overflow - let carry = (x_lo as u128 * y_lo as u128) >> 64; - let m = x_lo as u128 * y_hi as u128 + carry; - let high1 = m >> 64; - - let m_lo = m as u64; - let high2 = (x_hi as u128 * y_lo as u128 + m_lo as u128) >> 64; - - x_hi as u128 * y_hi as u128 + high1 + high2 -}