Jiufu Guo <guoji...@linux.ibm.com> writes:
Hi,
Patch is updated a little according to comments.
Please see if this is ok to commit.
diff --git a/gcc/common.opt b/gcc/common.opt
index 4464049fc1f..570e2aa53c8 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -2856,6 +2856,10 @@ funroll-all-loops
Common Report Var(flag_unroll_all_loops) Optimization
Perform loop unrolling for all loops.
+funroll-completely-grow-size
+Undocumented Var(flag_cunroll_grow_size) Init(2) Optimization
+; Internal undocumented flag, allow size growth during complete unrolling
+
; Nonzero means that loop optimizer may assume that the induction variables
; that control loops do not overflow and that the loops with nontrivial
; exit condition are not infinite
diff --git a/gcc/toplev.c b/gcc/toplev.c
index 96316fbd23b..e1010077ddb 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -1474,6 +1474,11 @@ process_options (void)
if (flag_unroll_all_loops)
flag_unroll_loops = 1;
+ /* Allow cunroll to grow size accordingly. */
+ if (flag_cunroll_grow_size == AUTODETECT_VALUE)
+ flag_cunroll_grow_size
+ = flag_unroll_loops || flag_peel_loops || optimize >= 3;
+
/* web and rename-registers help when run after loop unrolling. */
if (flag_web == AUTODETECT_VALUE)
flag_web = flag_unroll_loops;
diff --git a/gcc/tree-ssa-loop-ivcanon.c b/gcc/tree-ssa-loop-ivcanon.c
index 8ab6ab3330c..298ab215530 100644
--- a/gcc/tree-ssa-loop-ivcanon.c
+++ b/gcc/tree-ssa-loop-ivcanon.c
@@ -1603,9 +1603,8 @@ pass_complete_unroll::execute (function *fun)
re-peeling the same loop multiple times. */
if (flag_peel_loops)
peeled_loops = BITMAP_ALLOC (NULL);
- unsigned int val = tree_unroll_loops_completely (flag_unroll_loops
- || flag_peel_loops
- || optimize >= 3, true);
+ unsigned int val = tree_unroll_loops_completely (flag_cunroll_grow_size,
+ true);
if (peeled_loops)
{
BITMAP_FREE (peeled_loops);
BR,
Jiufu
> Richard Biener <richard.guent...@gmail.com> writes:
>
>> On Tue, Jun 2, 2020 at 4:10 AM Jiufu Guo <guoji...@linux.ibm.com> wrote:
>>>
>>> Jiufu Guo <guoji...@linux.ibm.com> writes:
>>>
>>> Hi,
>>>
>>> I updated the patch just a little accordinlgy. Thanks!
>>>
>>> diff --git a/gcc/common.opt b/gcc/common.opt
>>> index 4464049fc1f..570e2aa53c8 100644
>>> --- a/gcc/common.opt
>>> +++ b/gcc/common.opt
>>> @@ -2856,6 +2856,10 @@ funroll-all-loops
>>> Common Report Var(flag_unroll_all_loops) Optimization
>>> Perform loop unrolling for all loops.
>>>
>>> +funroll-completely-grow-size
>>> +Common Undocumented Var(flag_cunroll_grow_size) Init(2) Optimization
>>> +; Internal undocumented flag, allow size growth during complete unrolling
>>> +
>>> ; Nonzero means that loop optimizer may assume that the induction variables
>>> ; that control loops do not overflow and that the loops with nontrivial
>>> ; exit condition are not infinite
>>> diff --git a/gcc/toplev.c b/gcc/toplev.c
>>> index 96316fbd23b..8d52358efdd 100644
>>> --- a/gcc/toplev.c
>>> +++ b/gcc/toplev.c
>>> @@ -1474,6 +1474,10 @@ process_options (void)
>>> if (flag_unroll_all_loops)
>>> flag_unroll_loops = 1;
>>>
>>> + /* Allow cunroll to grow size accordingly. */
>>> + if (flag_cunroll_grow_size == AUTODETECT_VALUE)
>>> + flag_cunroll_grow_size = flag_unroll_loops || flag_peel_loops;
>>> +
>>
>> (*)
>>
>>> /* web and rename-registers help when run after loop unrolling. */
>>> if (flag_web == AUTODETECT_VALUE)
>>> flag_web = flag_unroll_loops;
>>> diff --git a/gcc/tree-ssa-loop-ivcanon.c b/gcc/tree-ssa-loop-ivcanon.c
>>> index 8ab6ab3330c..298ab215530 100644
>>> --- a/gcc/tree-ssa-loop-ivcanon.c
>>> +++ b/gcc/tree-ssa-loop-ivcanon.c
>>> @@ -1603,9 +1603,8 @@ pass_complete_unroll::execute (function *fun)
>>> re-peeling the same loop multiple times. */
>>> if (flag_peel_loops)
>>> peeled_loops = BITMAP_ALLOC (NULL);
>>> - unsigned int val = tree_unroll_loops_completely (flag_unroll_loops
>>> - || flag_peel_loops
>>> - || optimize >= 3, true);
>>> + unsigned int val = tree_unroll_loops_completely (flag_cunroll_grow_size,
>>
>> With -O3 -fno-peel-loops this does not have the same effect anymore.
>> So above (*) you'd need to check || optimize >= 3 as well.
>
> Oh, yes. Thanks for your kindly review!
>
> BR,
> Jiufu
>
>>
>>> + true);
>>> if (peeled_loops)
>>> {
>>> BITMAP_FREE (peeled_loops);
>>>
>>> BR,
>>> Jiufu
>>>
>>> > Richard Biener <richard.guent...@gmail.com> writes:
>>> >
>>>
>>> >>> >> From: Jiufu Guo <guoji...@linux.ibm.com>
>>> >>> >>
>>> >>> >> Currently GIMPLE complete unroller(cunroll) is checking
>>> >>> >> flag_unroll_loops and flag_peel_loops to see if allow size growth.
>>> >>> >> Beside affects curnoll, flag_unroll_loops also controls RTL unroler.
>>> >>> >> To have more freedom to control cunroll and RTL unroller, this patch
>>> >>> >> introduces flag_cunroll_grow_size. With this patch, we can control
>>> >>> >> cunroll and RTL unroller indepently.
>>> >>> >>
>>> >>> >> Bootstrap/regtest pass on powerpc64le. OK for trunk? And backport to
>>> >>> >> GCC10 after week?
>>> >>> >>
>>> >>> >>
>>> >>> >> +funroll-completely-grow-size
>>> >>> >> +Var(flag_cunroll_grow_size) Init(2)
>>> >>> >> +; Control cunroll to allow size growth during complete unrolling
>>> >>> >> +
>>> >>> >
>>> >>
>>> >> It won't work without adjusting the awk scripts. So go with
>>> >>
>>> >> funroll-completely-grow-size
>>> >> Undocumented Optimization Var(flag_cunroll_grow_size)
>>> >> EnabledBy(funroll-loops || fpeel-loops)
>>> >> ; ...
>>> >>
>>> > EnabledBy(funroll-loops || fpeel-loops) does not works as we expected:
>>> > "-funroll-loops -fno-peel-loops" turns off flag_cunroll_grow_size.
>>> >
>>> > Through "EnabledBy", a flag can be turned, and also can be turned off by
>>> > the "EnabledBy option", only if the flag is not specifed through commond
>>> > line.
>>> >
>>> >> and enable it at O3+. AUTODETECT_VALUE doesn't make sense for
>>> >> an option not supposed to be set by users?
>>> >>
>>> >
>>> > global_options_set.x_flagxxx can be used to check if option is set by
>>> > user. But it does not work well here neither, because we also care of
>>> > if the flag is override by OPTION_OPTIMIZATION_TABLE or
>>> > OPTION_OVERRIDE.
>>> >
>>> > AUTODETECT_VALUE(value is 2) is used for some flags like flag_web,
>>> > flag_rename_registers, flag_var_tracking, flag_tree_cselim...
>>> > And this way could be used to check if the flag is effective(on/off)
>>> > either explicit set by command line or implicit set through
>>> > OPTION_OVERRIDE or OPTION_OPTIMIZATION_TABLE.
>>> > So, I use it here.
>>>
>>>
