1*4a17663cSThomas Veerman$NetBSD: NOTES,v 1.2 2009/10/29 00:56:19 christos Exp $ 2*4a17663cSThomas Veerman 3*4a17663cSThomas VeermanBerkeley Yacc reflects its origins. The reason so many routines 4*4a17663cSThomas Veermanuse exactly six register variables is that Berkeley Yacc was 5*4a17663cSThomas Veermandeveloped on a VAX using PCC. PCC placed at most six variables 6*4a17663cSThomas Veermanin registers. I went to considerable effort to find which six 7*4a17663cSThomas Veermanvariables most belonged in registers. Changes in machines and 8*4a17663cSThomas Veermancompilers make that effort worthless, perhaps even harmful. 9*4a17663cSThomas Veerman 10*4a17663cSThomas Veerman[Given the previous paragraph, and the fact that GCC does not respect 11*4a17663cSThomas Veerman register declarations, and the fact that much of the rest of the 12*4a17663cSThomas Veerman 4.4lite2 release had "register" declarations extirpated, I've removed 13*4a17663cSThomas Veerman most of the register declarations from the code. I left them in the 14*4a17663cSThomas Veerman generated skeleton code "for the hell of it" but they probably should 15*4a17663cSThomas Veerman go from there, too. -- pm, July 1997] 16*4a17663cSThomas Veerman 17*4a17663cSThomas Veerman[I totally removed the register stuff; we've deprecated it elsewhere 18*4a17663cSThomas Veerman in the tree now -- lukem, October 1997] 19*4a17663cSThomas Veerman 20*4a17663cSThomas VeermanThe code contains many instances where address calculations are 21*4a17663cSThomas Veermanperformed in particular ways to optimize the code for the VAX. 22