Skip to content

Improve documentation for std::{f32,f64}::mul_add #77027

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
bors merged 2 commits into from
Dec 11, 2020
Merged

Improve documentation for std::{f32,f64}::mul_add #77027

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
72a5cbb
Edit documentation for `std::{f32,f64}::mul_add`.
fu5ha Sep 21, 2020
a6d98d8
generalize warning
fu5ha Oct 13, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 5 additions & 2 deletions library/std/src/f32.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -206,8 +206,11 @@ impl f32 {
/// Fused multiply-add. Computes `(self * a) + b` with only one rounding
/// error, yielding a more accurate result than an unfused multiply-add.
///
/// Using `mul_add` can be more performant than an unfused multiply-add if
/// the target architecture has a dedicated `fma` CPU instruction.
/// Using `mul_add` *can* be more performant than an unfused multiply-add if
/// the target architecture has a dedicated `fma` CPU instruction. However,
/// this is not always true, and care must be taken not to overload the
/// architecture's available FMA units when using many FMA instructions
/// in a row, which can cause a stall and performance degradation.
///
/// # Examples
///
Expand Down
7 changes: 5 additions & 2 deletions library/std/src/f64.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -206,8 +206,11 @@ impl f64 {
/// Fused multiply-add. Computes `(self * a) + b` with only one rounding
/// error, yielding a more accurate result than an unfused multiply-add.
///
/// Using `mul_add` can be more performant than an unfused multiply-add if
/// the target architecture has a dedicated `fma` CPU instruction.
/// Using `mul_add` *can* be more performant than an unfused multiply-add if
/// the target architecture has a dedicated `fma` CPU instruction. However,
/// this is not always true, and care must be taken not to overload the
/// architecture's available FMA units when using many FMA instructions
/// in a row, which can cause a stall and performance degradation.
///
/// # Examples
///
Expand Down