From 9a9e47798f903447ffc3beb89b22284009c30e3d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johanna=20S=C3=B6rng=C3=A5rd?=
 <44257381+JSorngard@users.noreply.github.com>
Date: Fri, 1 Nov 2024 13:29:03 +0100
Subject: [PATCH] Add some more basic docstrings (#352)

* Add docstrings to the tgamma functions
* Add docstrings to the lgamma functions
* Add docstrings to trunc
* Add docstrings to exp10 functions
---
 library/compiler-builtins/libm/src/math/exp10.rs   | 1 +
 library/compiler-builtins/libm/src/math/exp10f.rs  | 1 +
 library/compiler-builtins/libm/src/math/lgamma.rs  | 2 ++
 library/compiler-builtins/libm/src/math/lgammaf.rs | 2 ++
 library/compiler-builtins/libm/src/math/tgamma.rs  | 1 +
 library/compiler-builtins/libm/src/math/tgammaf.rs | 1 +
 library/compiler-builtins/libm/src/math/trunc.rs   | 3 +++
 library/compiler-builtins/libm/src/math/truncf.rs  | 3 +++
 8 files changed, 14 insertions(+)

diff --git a/library/compiler-builtins/libm/src/math/exp10.rs b/library/compiler-builtins/libm/src/math/exp10.rs
index 559930e109fe..2c3df0173441 100644
--- a/library/compiler-builtins/libm/src/math/exp10.rs
+++ b/library/compiler-builtins/libm/src/math/exp10.rs
@@ -6,6 +6,7 @@ const P10: &[f64] = &[
     1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13, 1e14, 1e15,
 ];
 
+/// Calculates 10 raised to the power of `x` (f64).
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn exp10(x: f64) -> f64 {
     let (mut y, n) = modf(x);
diff --git a/library/compiler-builtins/libm/src/math/exp10f.rs b/library/compiler-builtins/libm/src/math/exp10f.rs
index 786305481dcf..e81d18380b94 100644
--- a/library/compiler-builtins/libm/src/math/exp10f.rs
+++ b/library/compiler-builtins/libm/src/math/exp10f.rs
@@ -5,6 +5,7 @@ const LN10_F64: f64 = 3.32192809488736234787031942948939;
 const P10: &[f32] =
     &[1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7];
 
+/// Calculates 10 raised to the power of `x` (f32).
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn exp10f(x: f32) -> f32 {
     let (mut y, n) = modff(x);
diff --git a/library/compiler-builtins/libm/src/math/lgamma.rs b/library/compiler-builtins/libm/src/math/lgamma.rs
index a08bc5b641e4..8312dc18648e 100644
--- a/library/compiler-builtins/libm/src/math/lgamma.rs
+++ b/library/compiler-builtins/libm/src/math/lgamma.rs
@@ -1,5 +1,7 @@
 use super::lgamma_r;
 
+/// The natural logarithm of the
+/// [Gamma function](https://en.wikipedia.org/wiki/Gamma_function) (f64).
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn lgamma(x: f64) -> f64 {
     lgamma_r(x).0
diff --git a/library/compiler-builtins/libm/src/math/lgammaf.rs b/library/compiler-builtins/libm/src/math/lgammaf.rs
index a9c2da75bd77..d37512397cb3 100644
--- a/library/compiler-builtins/libm/src/math/lgammaf.rs
+++ b/library/compiler-builtins/libm/src/math/lgammaf.rs
@@ -1,5 +1,7 @@
 use super::lgammaf_r;
 
+/// The natural logarithm of the
+/// [Gamma function](https://en.wikipedia.org/wiki/Gamma_function) (f32).
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn lgammaf(x: f32) -> f32 {
     lgammaf_r(x).0
diff --git a/library/compiler-builtins/libm/src/math/tgamma.rs b/library/compiler-builtins/libm/src/math/tgamma.rs
index 60451416ab32..3059860646a5 100644
--- a/library/compiler-builtins/libm/src/math/tgamma.rs
+++ b/library/compiler-builtins/libm/src/math/tgamma.rs
@@ -130,6 +130,7 @@ fn s(x: f64) -> f64 {
     return num / den;
 }
 
+/// The [Gamma function](https://en.wikipedia.org/wiki/Gamma_function) (f64).
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn tgamma(mut x: f64) -> f64 {
     let u: u64 = x.to_bits();
diff --git a/library/compiler-builtins/libm/src/math/tgammaf.rs b/library/compiler-builtins/libm/src/math/tgammaf.rs
index 23e3814f99fd..fe178f7a3c0e 100644
--- a/library/compiler-builtins/libm/src/math/tgammaf.rs
+++ b/library/compiler-builtins/libm/src/math/tgammaf.rs
@@ -1,5 +1,6 @@
 use super::tgamma;
 
+/// The [Gamma function](https://en.wikipedia.org/wiki/Gamma_function) (f32).
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn tgammaf(x: f32) -> f32 {
     tgamma(x as f64) as f32
diff --git a/library/compiler-builtins/libm/src/math/trunc.rs b/library/compiler-builtins/libm/src/math/trunc.rs
index 6961bb950600..34bc2fdfa48c 100644
--- a/library/compiler-builtins/libm/src/math/trunc.rs
+++ b/library/compiler-builtins/libm/src/math/trunc.rs
@@ -1,5 +1,8 @@
 use core::f64;
 
+/// Rounds the number toward 0 to the closest integral value (f64).
+///
+/// This effectively removes the decimal part of the number, leaving the integral part.
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn trunc(x: f64) -> f64 {
     select_implementation! {
diff --git a/library/compiler-builtins/libm/src/math/truncf.rs b/library/compiler-builtins/libm/src/math/truncf.rs
index 8270c8eb392d..a74f78987723 100644
--- a/library/compiler-builtins/libm/src/math/truncf.rs
+++ b/library/compiler-builtins/libm/src/math/truncf.rs
@@ -1,5 +1,8 @@
 use core::f32;
 
+/// Rounds the number toward 0 to the closest integral value (f32).
+///
+/// This effectively removes the decimal part of the number, leaving the integral part.
 #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
 pub fn truncf(x: f32) -> f32 {
     select_implementation! {