https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83710
--- Comment #6 from Chanpreet Singh <chanpreet.singh at nxp dot com> --- (In reply to Andrew Pinski from comment #5) > (In reply to Chanpreet Singh from comment #4) > > (In reply to Andrew Pinski from comment #3) > > > For imull discussion see > > > https://stackoverflow.com/questions/42587607/why-is-imul-used-for- > > > multiplying-unsigned-numbers . > > > > I understand that. However, can you point to me what made the compiler > > choose shrl instruction over sarl? > > Again: unsigned * int produces a type of unsigned. And then the shift is > done in unsigned type. See comment #1. imull is used for both signed and > unsigned multiply :). Understand. For a moment, I thought comment#1 was talking about type casting. Can you provide me with some documentation? There are blogs that says otherwise http://www.avrfreaks.net/forum/tut-signed-and-unsigned-multiplication. Thanks for your clarification.
