From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joern Rennecke To: michaelh@ongaonga.chch.cri.nz (Michael P. Hayes) Cc: gcc2@cygnus.com, egcs@cygnus.com Subject: Re: Autoincrement addressing modes Date: Wed, 11 Feb 1998 16:33:00 -0000 Message-id: <199802112304.XAA11969@phal.cygnus.co.uk> References: <199802112206.LAA28349@ongaonga.chch.cri.nz> X-SW-Source: 1998-02/msg00507.html > At this stage I'm interested in what other common forms should be > supported. The SH doesn't have any exotic update forms, but it has another quirk in autoincrement that gcc doesn't handle efficiently: POST_INC is only available for reading, while PRE_DEC is only available for writing. There are some places in the compiler that just test POST_INC / PRE_DEC (or more generally HAVE_AUTO_INC) to check if an autoincrement might be generated in a later stage. It would be nice if these would be updated not only to handle the new address updates properly, but also only speculate the appropriatenes of an address update depending on the direction of the memory access.