On Thu, Oct 22, 2015 at 10:04 AM, Jakub Jelinek <ja...@redhat.com> wrote:
> On Wed, Oct 21, 2015 at 03:00:47PM -0400, Nathan Sidwell wrote:
>> To distinguish different uses of the UNIQUE function, I use the first
>> argument, which is expected to be an INTEGER_CST. I figured this better
>> than using multiple new internal fns, all with the unique property, as the
>> latter would need (at least) a range check in gimple_call_internal_unique_p
>> rather than a simple equality.
>>
>> Jakub, IYR I originally had IFN_FORK and IFN_JOIN as such distinct internal
>> fns. This replaces that scheme.
>>
>> ok?
>>
>> nathan
>
>> 2015-10-20 Nathan Sidwell <nat...@codesourcery.com>
>> Cesar Philippidis <ce...@codesourcery.com>
>>
>> * internal-fn.c (expand_UNIQUE): New.
>> * internal-fn.def (IFN_UNIQUE): New.
>> (IFN_UNIQUE_UNSPEC): Define.
>> * gimple.h (gimple_call_internal_unique_p): New.
>> * gimple.c (gimple_call_same_target_p): Check internal fn
>> uniqueness.
>> * tracer.c (ignore_bb_p): Check for IFN_UNIQUE call.
>> * tree-ssa-threadedge.c
>> (record_temporary_equivalences_from_stmts): Likewise.
>
> This is generally fine with me, but please work with Richi to find
> something acceptable to him too.
>
>> +DEF_INTERNAL_FN (UNIQUE, ECF_NOTHROW | ECF_LEAF, NULL)
>
> Are you sure about the ECF_LEAF? I mean, while the function can't
> call back to your code, I'd expect you want it as kind of strong
> optimization barrier too.
>
>> +#define IFN_UNIQUE_UNSPEC 0 /* Undifferentiated UNIQUE. */
>> Index: tracer.c
>> ===================================================================
>> --- tracer.c (revision 229096)
>> +++ tracer.c (working copy)
>> @@ -93,6 +93,7 @@ bb_seen_p (basic_block bb)
>> static bool
>> ignore_bb_p (const_basic_block bb)
>> {
>> + gimple_stmt_iterator gsi;
>> gimple *g;
>>
>> if (bb->index < NUM_FIXED_BLOCKS)
>> @@ -106,6 +107,17 @@ ignore_bb_p (const_basic_block bb)
>> if (g && gimple_code (g) == GIMPLE_TRANSACTION)
>> return true;
>>
>> + /* Ignore blocks containing non-clonable function calls. */
>> + for (gsi = gsi_start_bb (CONST_CAST_BB (bb));
>> + !gsi_end_p (gsi); gsi_next (&gsi))
>> + {
>> + g = gsi_stmt (gsi);
>> +
>> + if (is_gimple_call (g) && gimple_call_internal_p (g)
>> + && gimple_call_internal_unique_p (as_a <gcall *> (g)))
>> + return true;
>> + }
>
> Do you have to scan the whole bb? E.g. don't or should not those
> unique IFNs force end of bb?
Yeah, please make them either end or start a BB so we have to check
at most a single stmt. ECF_RETURNS_TWICE should achieve that,
it also makes it a code motion barrier.
Richard.
> Jakub
