| | x_unsupp.sa 3.3 7/1/91 | | fpsp_unsupp --- FPSP handler for unsupported data type exception | | Trap vector #55 (See table 8-1 Mc68030 User's manual). | Invoked when the user program encounters a data format (packed) that | hardware does not support or a data type (denormalized numbers or un- | normalized numbers). | Normalizes denorms and unnorms, unpacks packed numbers then stores | them back into the machine to let the 040 finish the operation. | | Unsupp calls two routines: | 1. get_op - gets the operand(s) | 2. res_func - restore the function back into the 040 or | if fmove.p fpm,<ea> then pack source (fpm) | and store in users memory <ea>. | | Input: Long fsave stack frame | | | Copyright (C) Motorola, Inc. 1990 | All Rights Reserved | | For details on the license for this file, please see the | file, README, in this same directory. X_UNSUPP: |idnt 2,1 | Motorola 040 Floating Point Software Package |section 8 #include "fpsp.h" |xref get_op |xref res_func |xref gen_except |xref fpsp_fmt_error .global fpsp_unsupp fpsp_unsupp: | link %a6,#-LOCAL_SIZE fsave -(%a7) moveml %d0-%d1/%a0-%a1,USER_DA(%a6) fmovemx %fp0-%fp3,USER_FP0(%a6) fmoveml %fpcr/%fpsr/%fpiar,USER_FPCR(%a6) moveb (%a7),VER_TMP(%a6) |save version number 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 fmovel #0,%FPSR |clear all user status bits fmovel #0,%FPCR |clear all user control bits | | The following lines are used to ensure that the FPSR | exception byte and condition codes are clear before proceeding, | except in the case of fmove, which leaves the cc's intact. | unsupp_con: movel USER_FPSR(%a6),%d1 btst #5,CMDREG1B(%a6) |looking for fmove out bne fmove_con andl #0xFF00FF,%d1 |clear all but aexcs and qbyte bras end_fix fmove_con: andl #0x0FFF40FF,%d1 |clear all but cc's, snan bit, aexcs, and qbyte end_fix: movel %d1,USER_FPSR(%a6) st UFLG_TMP(%a6) |set flag for unsupp data bsrl get_op |everything okay, go get operand(s) bsrl res_func |fix up stack frame so can restore it clrl -(%a7) moveb VER_TMP(%a6),(%a7) |move idle fmt word to top of stack bral gen_except | |end |