1 | 2 | x_unsupp.sa 3.3 7/1/91 3 | 4 | fpsp_unsupp --- FPSP handler for unsupported data type exception 5 | 6 | Trap vector #55 (See table 8-1 Mc68030 User's manual). 7 | Invoked when the user program encounters a data format (packed) that 8 | hardware does not support or a data type (denormalized numbers or un- 9 | normalized numbers). 10 | Normalizes denorms and unnorms, unpacks packed numbers then stores 11 | them back into the machine to let the 040 finish the operation. 12 | 13 | Unsupp calls two routines: 14 | 1. get_op - gets the operand(s) 15 | 2. res_func - restore the function back into the 040 or 16 | if fmove.p fpm,<ea> then pack source (fpm) 17 | and store in users memory <ea>. 18 | 19 | Input: Long fsave stack frame 20 | 21 | 22 23 | Copyright (C) Motorola, Inc. 1990 24 | All Rights Reserved 25 | 26 | For details on the license for this file, please see the 27 | file, README, in this same directory. 28 29 X_UNSUPP: |idnt 2,1 | Motorola 040 Floating Point Software Package 30 31 |section 8 32 33 #include "fpsp.h" 34 35 |xref get_op 36 |xref res_func 37 |xref gen_except 38 |xref fpsp_fmt_error 39 40 .global fpsp_unsupp 41 fpsp_unsupp: 42 | 43 link %a6,#-LOCAL_SIZE 44 fsave -(%a7) 45 moveml %d0-%d1/%a0-%a1,USER_DA(%a6) 46 fmovemx %fp0-%fp3,USER_FP0(%a6) 47 fmoveml %fpcr/%fpsr/%fpiar,USER_FPCR(%a6) 48 49 50 moveb (%a7),VER_TMP(%a6) |save version number 51 moveb (%a7),%d0 |test for valid version num 52 andib #0xf0,%d0 |test for $4x 53 cmpib #VER_4,%d0 |must be $4x or exit 54 bnel fpsp_fmt_error 55 56 fmovel #0,%FPSR |clear all user status bits 57 fmovel #0,%FPCR |clear all user control bits 58 | 59 | The following lines are used to ensure that the FPSR 60 | exception byte and condition codes are clear before proceeding, 61 | except in the case of fmove, which leaves the cc's intact. 62 | 63 unsupp_con: 64 movel USER_FPSR(%a6),%d1 65 btst #5,CMDREG1B(%a6) |looking for fmove out 66 bne fmove_con 67 andl #0xFF00FF,%d1 |clear all but aexcs and qbyte 68 bras end_fix 69 fmove_con: 70 andl #0x0FFF40FF,%d1 |clear all but cc's, snan bit, aexcs, and qbyte 71 end_fix: 72 movel %d1,USER_FPSR(%a6) 73 74 st UFLG_TMP(%a6) |set flag for unsupp data 75 76 bsrl get_op |everything okay, go get operand(s) 77 bsrl res_func |fix up stack frame so can restore it 78 clrl -(%a7) 79 moveb VER_TMP(%a6),(%a7) |move idle fmt word to top of stack 80 bral gen_except 81 | 82 |end 83