From mboxrd@z Thu Jan 1 00:00:00 1970 From: jtc@redback.com (J.T. Conklin) To: Michael Hayes Cc: Stan Shebs , gdb@sourceware.cygnus.com Subject: Re: Proposal for handling large numbers of registers Date: Fri, 06 Aug 1999 18:27:00 -0000 Message-id: <5mwvv82xei.fsf@jtc.redbacknetworks.com> References: <199908062333.QAA16667@andros.cygnus.com> <14251.31513.361599.969792@ongaonga.elec.canterbury.ac.nz> X-SW-Source: 1999-q3/msg00124.html >> So I'm considering importing the idea of "register classes" from >> GCC. GCC uses the class idea to guide allocation and instruction >> selection, but we don't even need that much; just define the names >> of the classes and which registers belong to each. > It would be nice if one could just cut the register class > definitions from gcc tm.h and paste them into gdb tm.h. I'm not sure that a compilers notion of register classes make sense for debugging and vice versa. For debugging, broad categories like "integer registers", "floating point registers", "system registers" seem to be most appropriate; while compilers think of classes like "registers that can be used for indexing", "special register used for integer divide instructions", etc. --jtc -- J.T. Conklin RedBack Networks >From m.hayes@elec.canterbury.ac.nz Fri Aug 06 18:36:00 1999 From: Michael Hayes To: jtc@redback.com Cc: Michael Hayes , Stan Shebs , gdb@sourceware.cygnus.com Subject: Re: Proposal for handling large numbers of registers Date: Fri, 06 Aug 1999 18:36:00 -0000 Message-id: <14251.35343.506647.777893@ongaonga.elec.canterbury.ac.nz> References: <199908062333.QAA16667@andros.cygnus.com> <14251.31513.361599.969792@ongaonga.elec.canterbury.ac.nz> <5mwvv82xei.fsf@jtc.redbacknetworks.com> X-SW-Source: 1999-q3/msg00125.html Content-length: 679 J.T. Conklin writes: > I'm not sure that a compilers notion of register classes make sense > for debugging and vice versa. For debugging, broad categories like > "integer registers", "floating point registers", "system registers" > seem to be most appropriate; while compilers think of classes like > "registers that can be used for indexing", "special register used > for integer divide instructions", etc. For most targets I have looked at, these other classes you mention are usually sub-classes of the "integer registers", "fp registers", etc. However, I can see from most user's perspectives that they will not be interested in these special sub-classes. Michael.