https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106210
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |NEW
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
By using the dump file:
-fdump-rtl-pro_and_epologue
You will see if it was shrink wrapped (which it does in GCC 5.x):
Performing shrink-wrapping.
While the full dump in GCC 6 has:
Attempting shrink-wrapping optimization.
Block 2 needs the prologue.
Block 4 needs the prologue.
After wrapping required blocks, PRO is now 2
Avoiding non-duplicatable blocks, PRO is now 2
Bumping back to anticipatable blocks, PRO is now 2
Here is the part of the dump for GCC 5 which shows the full thing:
Attempting shrink-wrapping optimization.
insn 6: replaced reg 1 with 0
rescanning insn with uid = 6.
Found candidate edge for shrink-wrapping, 2->4.
Performing shrink-wrapping.
changing bb of uid 60
unscanned insn
Duplicating bb 5 to bb 6, 0 active insns.
scanning new insn with uid = 64.
Removing jump 48.
