https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95738
Bug ID: 95738
Summary: Failure to optimize comparison of float after sign xor
to unsigned comparison
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: gabravier at gmail dot com
Target Milestone: ---
typedef int64_t v2i64 __attribute__((vector_size(16)));
typedef uint64_t v2u64 __attribute__((vector_size(16)));
v2i64 f(v2i64 a, v2i64 b)
{
auto sign = (v2i64){(int64_t)0x8000000000000000u,
(int64_t)0x8000000000000000u};
return (a ^ sign) > (b ^ sign);
}
This can be optimized to `(v2u64)a > (v2u64)b`. This transformation is done by
LLVM, but not by GCC.
