On 11/18/22 23:25, Hongyu Wang via Gcc-patches wrote:
Hi,
Followed by the discussion in pr107602, -munroll-only-small-loops
Does not turns on/off -funroll-loops, and current check in
pass_rtl_unroll_loops::gate would cause -funroll-loops do not take
effect. Revert the change about targetm.loop_unroll_adjust and apply
the backend option change to strictly follow the rule that
-funroll-loops takes full control of loop unrolling, and
munroll-only-small-loops just change its behavior to unroll small size
loops.
Bootstrapped and regtested on x86-64-pc-linux-gnu.
Ok for trunk?
gcc/ChangeLog:
PR target/107602
* common/config/i386/i386-common.cc (ix86_optimization_table):
Enable loop unroll O2, disable -fweb and -frename-registers
by default.
* config/i386/i386-options.cc
(ix86_override_options_after_change):
Disable small loop unroll when funroll-loops enabled, reset
cunroll_grow_size when it is not explicitly enabled.
(ix86_option_override_internal): Call
ix86_override_options_after_change instead of calling
ix86_recompute_optlev_based_flags and ix86_default_align
separately.
* config/i386/i386.cc (ix86_loop_unroll_adjust): Adjust unroll
factor if -munroll-only-small-loops enabled.
* loop-init.cc (pass_rtl_unroll_loops::gate): Do not enable
loop unrolling for -O2-speed.
(pass_rtl_unroll_loops::execute): Rmove
targetm.loop_unroll_adjust check.
The reversion of the loop-init.cc changes is fine. The x86 maintainers
will need to chime in on the rest. Consider installing the loop-init.cc
reversion immediately as the current state has regressed s390 and
potentially other targets.
jeff
