[Bug d/109221] std.math.floor, core.math.ldexp, std.math.poly poor inlining

[witold.baryluk+gcc at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109221

--- Comment #1 from Witold Baryluk <witold.baryluk+gcc at gmail dot com> ---
PS. LDC 1.23.0 - 1.32.0 produce optimal code. LDC 1.22.0 a bit worse (due to
use of x87 codegen), and 1.21 and older fail to inline `ldexp`, but still
inline `poly` and `floor` perfectly.