[Bug middle-end/91709] Missed optimization for multiplication on 1.5 and 1.25

[antoshkka at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91709

--- Comment #3 from Antony Polukhin <antoshkka at gmail dot com> ---
(In reply to joseph@codesourcery.com from comment #2)
> If the result of multiplying by 1.5 is outside the range of the integer 
> type, the version with multiplication is required to raise the FE_INVALID 
> exception for the out-of-range conversion to integer

My reading of the C++ standard tells that such conversion is an undefined
behavior: http://eel.is/c++draft/conv.fpint#1

Is it really required to raise FE_INVALID ?