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#! | 9 lines | 8 code | 1 blank | 0 comment | 0 complexity | c4fe2270154478c523ebb4f4f0458941 MD5 | raw file
1Berkeley Yacc reflects its origins.  The reason so many routines
2use exactly six register variables is that Berkeley Yacc was
3developed on a VAX using PCC.  PCC placed at most six variables
4in registers.  I went to considerable effort to find which six
5variables most belonged in registers.  Changes in machines and
6compilers make that effort worthless, perhaps even harmful.
8The code contains many instances where address calculations are
9performed in particular ways to optimize the code for the VAX.