git: 2b2cd97844b8 - main - msun: Fix math error in comment explaining y reduction

The branch main has been updated by imp:

URL: https://cgit.FreeBSD.org/src/commit/?id=2b2cd97844b81e4a45504c90a791c3c3509898ad

commit 2b2cd97844b81e4a45504c90a791c3c3509898ad
Author:     Henri Chataing <henrichataing@google.com>
AuthorDate: 2024-04-12 22:08:01 +0000
Commit:     Warner Losh <imp@FreeBSD.org>
CommitDate: 2024-04-12 22:15:04 +0000

    msun: Fix math error in comment explaining y reduction
    
    x = k + y for some integer k and |y| < 1/2
    exp2(x) = exp2(k + y) = exp2(k) * exp2(y)
    which can be written as 2**k * exp2(y)
    
    The original had x = 2**k + y, which is has an extra 2** in it which
    isn't correct.
    
    Confirmed by forumula 2 in Gal and Bachelis referenced in the comments
    for the source of this method
            https://dl.acm.org/doi/pdf/10.1145/103147.103151
    
    The actual code is correct.
    
    Reviewed by: imp (who added s_exp2.c and wrote the commit message)
    Pull Request: https://github.com/freebsd/freebsd-src/pull/1127
---
 lib/msun/src/s_exp2.c  | 2 +-
 lib/msun/src/s_exp2f.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/msun/src/s_exp2.c b/lib/msun/src/s_exp2.c
index 338312f0de97..2064d22f44f3 100644
--- a/lib/msun/src/s_exp2.c
+++ b/lib/msun/src/s_exp2.c
@@ -314,7 +314,7 @@ static const double tbl[TBLSIZE * 2] = {
  * Method: (accurate tables)
  *
  *   Reduce x:
- *     x = 2**k + y, for integer k and |y| <= 1/2.
+ *     x = k + y, for integer k and |y| <= 1/2.
  *     Thus we have exp2(x) = 2**k * exp2(y).
  *
  *   Reduce y:
diff --git a/lib/msun/src/s_exp2f.c b/lib/msun/src/s_exp2f.c
index 85edd611944e..c863b7512194 100644
--- a/lib/msun/src/s_exp2f.c
+++ b/lib/msun/src/s_exp2f.c
@@ -72,7 +72,7 @@ static const double exp2ft[TBLSIZE] = {
  * Method: (equally-spaced tables)
  *
  *   Reduce x:
- *     x = 2**k + y, for integer k and |y| <= 1/2.
+ *     x = k + y, for integer k and |y| <= 1/2.
  *     Thus we have exp2f(x) = 2**k * exp2(y).
  *
  *   Reduce y: