x_unimp.S (2014B)
1| 2| x_unimp.sa 3.3 7/1/91 3| 4| fpsp_unimp --- FPSP handler for unimplemented instruction 5| exception. 6| 7| Invoked when the user program encounters a floating-point 8| op-code that hardware does not support. Trap vector# 11 9| (See table 8-1 MC68030 User's Manual). 10| 11| 12| Note: An fsave for an unimplemented inst. will create a short 13| fsave stack. 14| 15| Input: 1. Six word stack frame for unimplemented inst, four word 16| for illegal 17| (See table 8-7 MC68030 User's Manual). 18| 2. Unimp (short) fsave state frame created here by fsave 19| instruction. 20| 21| 22| Copyright (C) Motorola, Inc. 1990 23| All Rights Reserved 24| 25| For details on the license for this file, please see the 26| file, README, in this same directory. 27 28X_UNIMP: |idnt 2,1 | Motorola 040 Floating Point Software Package 29 30 |section 8 31 32#include "fpsp.h" 33 34 |xref get_op 35 |xref do_func 36 |xref sto_res 37 |xref gen_except 38 |xref fpsp_fmt_error 39 40 .global fpsp_unimp 41 .global uni_2 42fpsp_unimp: 43 link %a6,#-LOCAL_SIZE 44 fsave -(%a7) 45uni_2: 46 moveml %d0-%d1/%a0-%a1,USER_DA(%a6) 47 fmovemx %fp0-%fp3,USER_FP0(%a6) 48 fmoveml %fpcr/%fpsr/%fpiar,USER_FPCR(%a6) 49 moveb (%a7),%d0 |test for valid version num 50 andib #0xf0,%d0 |test for $4x 51 cmpib #VER_4,%d0 |must be $4x or exit 52 bnel fpsp_fmt_error 53| 54| Temporary D25B Fix 55| The following lines are used to ensure that the FPSR 56| exception byte and condition codes are clear before proceeding 57| 58 movel USER_FPSR(%a6),%d0 59 andl #0xFF00FF,%d0 |clear all but accrued exceptions 60 movel %d0,USER_FPSR(%a6) 61 fmovel #0,%FPSR |clear all user bits 62 fmovel #0,%FPCR |clear all user exceptions for FPSP 63 64 clrb UFLG_TMP(%a6) |clr flag for unsupp data 65 66 bsrl get_op |go get operand(s) 67 clrb STORE_FLG(%a6) 68 bsrl do_func |do the function 69 fsave -(%a7) |capture possible exc state 70 tstb STORE_FLG(%a6) 71 bnes no_store |if STORE_FLG is set, no store 72 bsrl sto_res |store the result in user space 73no_store: 74 bral gen_except |post any exceptions and return 75 76 |end