On 10/25/22 15:01, Aldy Hernandez via Gcc-patches wrote:
[Richi/Jakub/FP experts, does this sound like the right solution, or am I
missing some subtle IPA/inlining issue?]
The problem here is that we're inlining a global range with NANs into
a function that has been tagged with __attribute__((optimize
("-ffinite-math-only"))). As the global range is copied from
SSA_NAME_RANGE_INFO, its NAN bits are copied, which then cause
frange::verify_range() to fail a sanity check making sure no NANs
creep in when !HONOR_NANS.
I think what we should do is nuke the NAN bits as we're restoring the
global range. For that matter, if we use the frange constructor,
everything except that NAN sign will be done automatically, including
dropping INFs to the min/max representable range when appropriate.
PR tree-optimization/107394
gcc/ChangeLog:
* value-range-storage.cc (frange_storage_slot::get_frange): Use
frange constructor.
gcc/testsuite/ChangeLog:
* gcc.dg/tree-ssa/pr107394.c: New test.
The other approach would be to disabling inlining in this case due to an
unsafe attribute mismatch, but we're not currently doing much sanity
checking in this space and it might be a huge can of worms. I'm
inclined to ACK, but give Jakub and Richi until Monday to chime in first.
jeff
