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
29X_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
41fpsp_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|
63unsupp_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
69fmove_con:
70	andl		#0x0FFF40FF,%d1	|clear all but cc's, snan bit, aexcs, and qbyte
71end_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