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//

//      $Id: x_unimp.S,v 1.2 2001-09-27 12:01:22 chris Exp $

//

//      x_unimp.sa 3.3 7/1/91

//

//      fpsp_unimp --- FPSP handler for unimplemented instruction

//      exception.

//

// Invoked when the user program encounters a floating-point

// op-code that hardware does not support.  Trap vector# 11

// (See table 8-1 MC68030 User's Manual).

//

//

// Note: An fsave for an unimplemented inst. will create a short

// fsave stack.

//

//  Input: 1. Six word stack frame for unimplemented inst, four word

//            for illegal

//            (See table 8-7 MC68030 User's Manual).

//         2. Unimp (short) fsave state frame created here by fsave

//            instruction.

//

//

//              Copyright (C) Motorola, Inc. 1990

//                      All Rights Reserved

//

//      THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA

//      The copyright notice above does not evidence any

//      actual or intended publication of such source code.

X_UNIMP:        //idnt    2,1 | Motorola 040 Floating Point Software Package

        |section        8

#include "fpsp.defs"

        |xref   get_op

        |xref   do_func

        |xref   sto_res

        |xref   gen_except

        |xref   fpsp_fmt_error

        .global fpsp_unimp

        .global uni_2

fpsp_unimp:

        link            %a6,#-LOCAL_SIZE

        fsave           -(%a7)

uni_2:

        moveml          %d0-%d1/%a0-%a1,USER_DA(%a6)

        fmovemx %fp0-%fp3,USER_FP0(%a6)

        fmoveml %fpcr/%fpsr/%fpiar,USER_FPCR(%a6)

        moveb           (%a7),%d0               //test for valid version num

        andib           #0xf0,%d0               //test for $4x

        cmpib           #VER_4,%d0      //must be $4x or exit

        bnel            fpsp_fmt_error

//

//      Temporary D25B Fix

//      The following lines are used to ensure that the FPSR

//      exception byte and condition codes are clear before proceeding

//

        movel           USER_FPSR(%a6),%d0

        andl            #0xFF00FF,%d0   //clear all but accrued exceptions

        movel           %d0,USER_FPSR(%a6)

        fmovel          #0,%FPSR //clear all user bits

        fmovel          #0,%FPCR        //clear all user exceptions for FPSP

        clrb            UFLG_TMP(%a6)   //clr flag for unsupp data

        bsrl            get_op          //go get operand(s)

        clrb            STORE_FLG(%a6)

        bsrl            do_func         //do the function

        fsave           -(%a7)          //capture possible exc state

        tstb            STORE_FLG(%a6)

        bnes            no_store        //if STORE_FLG is set, no store

        bsrl            sto_res         //store the result in user space

no_store:

        bral            gen_except      //post any exceptions and return

        |end