https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91374
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Version|tree-ssa |10.0
Keywords| |missed-optimization
Last reconfirmed| |2019-08-07
Component|tree-optimization |ipa
CC| |jamborm at gcc dot gnu.org,
| |marxin at gcc dot gnu.org
Ever confirmed|0 |1
Severity|normal |enhancement
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
So you ask for main to be converted to
if (idx == 0)
foo_32_16 ();
else /* idx == 1 */
foo_16_8 ();
correct? It shoulds like an interesting idea for an IPA-CP cloning
opportunity. But I wonder how much real-world testcases exists
that are not benchmarks ;) One could tell by implementing the
analysis into the param analysis stage (look for defs that are
loads from a constant initialized entity, possibly multiple of them
and (some of them) reusing the same memory index). A related thing
would be to value-profile the indexes since when the array doesn't
only contain two values it isn't feasible to clone for all possible
values.
