From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Mitchell To: amylaar@cygnus.co.uk Cc: geoffk@cygnus.com, gcc@gcc.gnu.org Subject: Re: ssa bootstrap problem on x86 (cmpstrsi_1 pattern) Date: Thu, 27 Jul 2000 17:22:00 -0000 Message-id: <20000727172208M.mitchell@codesourcery.com> References: <20000727160116P.mitchell@codesourcery.com> <200007272359.AAA01850@phal.cygnus.co.uk> X-SW-Source: 2000-07/msg00892.html >>>>> "Joern" == Joern Rennecke writes: >> The only reason clobbers appear this early in the compiler is >> that GCC generates machine-specific code very early. There is >> no operation Joern> That is not true. When gcc synthesizes a move that is Joern> wider than the widest one available in the machine Joern> description, it first clobbers the destination, then does a Joern> series of moves into SUBREGs of the destination. But, again, isn't that a machine-specific issue? These moves could be represented directly as a SET and then resolved to an operation involving SUBREGs and CLOBBERs later. -- Mark Mitchell mark@codesourcery.com CodeSourcery, LLC http://www.codesourcery.com