Tracking Issue for `const_mul_add`

[tgross35]

Feature gate: #![feature(const_mul_add)]

This is a tracking issue for making mul_add const.

Public API

impl {f16, f32, f64, f128} {
    pub const fn mul_add(self, a: Self, b: Self) -> Self;
}

Steps / History

(Remember to update the S-tracking-* label when checking boxes.)

• Implementation: unstably constify float mul_add methods #146735
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• None yet.

Footnotes

1. https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html ↩

[tgross35]

Cc @rust-lang/libs-api @RalfJung: after the recent constification of rounding methods, this is the last float op supported by rustc_apfloat but not yet made const.

Labeled help wanted if anyone is interested in picking it up. The PR should look pretty similar to @ruancomelli's #141521 (move the implementation from miri to rustc_const_eval, move tests from library/coretests/tests/floats/f*.rs to library/coretests/tests/floats/mod.rs so they also get tested in const)

[kliwongan]

@rustbot claim

[tgross35]

@kliwongan thanks for the interest! There is a PR open here already though #146735.

(I can't reassign @Qelxiros directly)

[kliwongan]

Oh no problem, I'll just try another issue for now