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//  @(#)roundingmodelogic.v	1.1  4/7/92
//

module RoundModeLogic (Phi,
                  OprRoundMode,
                  LoadOprs,
                  notAbortWB,
                  CMPDecoded, CMPEDecoded,
                  RomSetRModeMinus,
                  RModeMinus,
                  U_RoundingMode);
input Phi;
input [1:0] OprRoundMode;
input LoadOprs,
      notAbortWB,
      CMPDecoded, CMPEDecoded,
      RomSetRModeMinus;

output RModeMinus;
output [1:0] U_RoundingMode;
/* *************************************** */
/* Rounding Mode Latch                     */
/* *************************************** */

/* In addition to being the rounding mode this latch is also used in
   the compares to signal between the two different types Invalid/Vailid
   on unordered. This is TACKY but saves a lot of code
   Additional inputs CMPE and CMP distinguish between the two types
   It isnt a big problem because RMode is part of the instruction not
   ME_ROM and so no timing problems will occur */
wire [1:0] notModifiedRMode, notRoundingMode, RoundingMode;

ME_INVA cmpbits  (CMPDecoded, notCMPDecoded);
ME_AND2 rmcmp1   (OprRoundMode[1], notCMPDecoded, CMPRMode1);
ME_AND2_B fgf    (RomSetRModeMinus, notAbortWB, RModeFromMinus);
ME_NOR3 rmcmpe1  (CMPRMode1, CMPEDecoded, RModeFromMinus, notModifiedRMode[1]);
ME_NOR3 rmcmpe0  (OprRoundMode[0], CMPEDecoded,    RModeFromMinus, notModifiedRMode[0]);

/* RoundingMode is latched from status register at the begining of
   a new instruction. It is transient therefore. */

ME_OR2_B fgfo (RModeFromMinus, LoadOprs, RMLatchEnable);

ME_NMUX2B rm0m (RMLatchEnable, notRoundingMode[0], notModifiedRMode[0], U_RoundingMode[0]);
ME_FD1    rm0f (Phi, U_RoundingMode[0], RoundingMode[0], notRoundingMode[0]);
ME_NMUX2B rm1m (RMLatchEnable, notRoundingMode[1], notModifiedRMode[1], U_RoundingMode[1]);
ME_FD1    rm1f (Phi, U_RoundingMode[1], RoundingMode[1], notRoundingMode[1]);

ME_AND2 rmc (RoundingMode[0], RoundingMode[1], RModeMinus); 
endmodule