IFUPLAFetchPreDecode.mesa
Copyright © 1984 by Xerox Corporation. All rights reserved.
Last edited by Twilliams, August 27, 1984 6:28:59 pm PDT
Last edited by Curry, June 1, 1986 6:41:03 pm PDT
Last edited by Herrmann, August 14, 1985 12:42:42 pm PDT
Last edited by McCreight, March 24, 1986 10:14:03 am PST
DIRECTORY
PLAOps;
IFUPLAFetchPreDecode: CEDAR DEFINITIONS =
BEGIN
FetchPreDecodeIn: TYPE = RECORD [ -- default must be zero
op:    [0..8) ← 0, -- 3 msbs of DragOpsCross.Inst,
fetchBytesM1: [0..32) ← 0,
iPFaulting:  BOOLFALSE ];
FetchPreDecodeOut: TYPE = RECORD [-- default must be zero
notInstReady:  BOOLFALSE,
jumpOffset:   JumpOffsetSel ← beta,
instFault0:   BOOLFALSE,
opLength:   [0..7] ← 0, -- A latched copy for fetch indexing
opLengthb:   [0..7] ← 0 ]; -- B latched copy for pc adjustment
JumpOffsetSel: TYPE = MACHINE DEPENDENT
{beta(0), alpha(3), alphaBeta(5), xa(9)}; -- +pc
END.