[Bug middle-end/122871] [13/14/15/16 Regression] de-optimized synthesis of long long shift and add

[avieira at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122871

--- Comment #6 from avieira at gcc dot gnu.org ---
Yeah this hack also makes that generate the 'add r1, r1, r0, lsl #1', which is
a bonus.