[ont.events] UW CS Colloq., Mr. Cordy on "An Orthogonal Model for Code Generation"

mwang@watmath.UUCP (mwang) (04/22/85)

         DEPARTMENT OF COMPUTER SCIENCE
         UNIVERSITY OF WATERLOO

         COMPUTER SCIENCE COLLOQUIUM

                             - Wednesday, May 1, 1985.

         Mr.  J.R. Cordy of the University of Toronto will speak
         on ``An Orthogonal Model for Code Generation''.

         TIME:                3:30 PM

         ROOM:              MC 5158

         ABSTRACT

         Code  generation  is  the  part of programming language
         compilation which is concerned with choosing the actual
         implementation  of  programming  language constructs in
         terms  of  computer  hardware.  We can characterize the
         code generation problem as a mapping from the abstract,
         mathematical world of programming languages to the con-
         crete,  discrete  world of computing machines.  Objects
         in  each  of  these worlds can be expressed in terms of
         two fundamental concepts: operators and operands.

         Viewed  in this way, every existing systematic approach
         to  code  generation  is based on the same model.  This
         traditional   model   begins  by  decomposing  abstract
         operand structure into sequences of abstract operators.
         Machine implementation is then accomplished as a single
         complex  process  which  tends  to  obscure the mapping
         between  language objects and their machine representa-
         tion.

         We  propose  a  new model, which we call the orthogonal
         model,  which  separates the implementation of abstract
         operators  and  abstract  operands into two essentially
         independent  parts.   In the orthogonal model, abstract
         operand  structure  is left intact until implementation
         of  abstract operators is complete.  It then remains to
         implement abstract operands as a separate step.

         We  present  a  code  generator structure based on this
         model, which is simpler and more easily understood than
         existing structures.  We present fundamental algorithms
         of  the  orthogonal  code  generator and show how these
          algorithms  can  be easily parameterized across a large
          class of target computers.

          Coffee and refreshments will be served at 3:15 pm.