https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123268
--- Comment #2 from Robin Dapp <rdapp at gcc dot gnu.org> ---
It's the following match.pd pattern that fre happens to invoke:
/* Transform x * { 0 or 1, 0 or 1, ... } into x & { 0 or -1, 0 or -1, ...},
unless the target has native support for the former but not the latter. */
(simplify
(mult @0 VECTOR_CST@1)
(if (initializer_each_zero_or_onep (@1)
...
I guess that's via try_conditional_simplification which strips cond, len, else,
etc. from an IFN and simplifies the underlying operation, then adds it back.
We probably don't have too many patterns that go from float to int and this
particular case where the else value is stale just never happened?
In convert_conditional_op when we put the IFN back together we don't verify
that the operand types (or orig_op.type) and the else value's type match.
Maybe we should? Another case where IFN type checking would help :)
On the other hand, the float zero is special and we could convert it to an
integer zero?
