~mdw / ssr / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Initial revision
[ssr] / StraySrc / Libraries / Steel / s / wimp_stat
1 ;
2 ; wimp_stat.s
3 ;
4 ; Special static parts of wimp
5 ;
6 ; © 1994-1998 Straylight
7 ;
8
9 ;----- Licensing note -------------------------------------------------------
10 ;
11 ; This file is part of Straylight's Steel library.
12 ;
13 ; Steel is free software; you can redistribute it and/or modify
14 ; it under the terms of the GNU General Public License as published by
15 ; the Free Software Foundation; either version 2, or (at your option)
16 ; any later version.
17 ;
18 ; Steel is distributed in the hope that it will be useful,
19 ; but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ; GNU General Public License for more details.
22 ;
23 ; You should have received a copy of the GNU General Public License
24 ; along with Steel. If not, write to the Free Software Foundation,
25 ; 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26
27 ;----- Standard header ------------------------------------------------------
28
29 GET libs:header
30 GET libs:SWIs
31
32 ;----- Private data ---------------------------------------------------------
33
34 AREA |C$$data|,DATA
35
36 wimp__savefp DCD 1
37
38 ;----- Some flags and things -----------------------------------------------
39
40 dpoll__savefp EQU 1<<24 ;Bit to set to save FP state
41
42 ;----- Polling code ---------------------------------------------------------
43
44 AREA |C$$Code|,CODE,READONLY
45
46 ; --- wimp_poll ---
47 ;
48 ; On entry: a1 == Wimp_Poll event mask
49 ; a2 == pointer to wimp_eventstr to be filled in
50 ; On exit: a1 == pointer to an os_error, or nothing
51
52 EXPORT wimp_poll
53 wimp_poll ROUT
54
55 STMFD sp!,{lr} ;Look after some registers
56
57 ; --- Figure out about saving the FP status ---
58
59 LDR a4,=wimp__savefp ;Find the magic flag
60 LDR a4,[a4] ;Get the value of the flag
61 CMP a4,#0 ;Do we have to save FP state?
62 ORRNE a1,a1,#dpoll__savefp ;Yes -- set the flag
63 BICNE a1,a1,#dpoll__savefp ;No -- clear the flag
64
65 ; --- Call the SWI and get out again ---
66
67 ADD a2,a2,#4 ;Point to the big poll block
68 BL wimp__doPoll ;Get a Wimp event
69 SUB a2,a2,#4 ;Point to the wimp_eventstr
70 STRVC a1,[a2] ;Store the reason code away
71 MOVVC a1,#0 ;If no error, return NULL
72 LDMFD sp!,{pc}^ ;Return to caller nicely
73
74 LTORG
75
76 ; --- wimp_pollidle ---
77 ;
78 ; On entry: a1 == Wimp_Poll event mask
79 ; a2 == pointer to wimp_eventstr to be filled in
80 ; a3 == time before which thou shalt not return
81 ; On exit: a1 == pointer to an os_error, or nothing
82
83 EXPORT wimp_pollidle
84 wimp_pollidle ROUT
85
86 STMFD sp!,{v1-v3,lr} ;Look after some registers
87
88 ; --- Figure out about saving the FP status ---
89
90 LDR a4,=wimp__savefp ;Find the magic flag
91 LDR a4,[a4] ;Get the value of the flag
92 CMP a4,#0 ;Do we have to save FP state?
93 ORRNE a1,a1,#dpoll__savefp ;Yes -- set the flag
94 BICNE a1,a1,#dpoll__savefp ;No -- clear the flag
95
96 ; --- Call the SWI and get out again ---
97
98 ADD a2,a2,#4 ;Point to the big poll block
99 BL wimp__doPollIdle ;Get a Wimp event
100 SUB a2,a2,#4 ;Point to the wimp_eventstr
101 STRVC a1,[a2] ;Store the reason code away
102 MOVVC a1,#0 ;If no error, return NULL
103 LDMFD sp!,{v1-v3,pc}^ ;Return to caller nicely
104
105 LTORG
106
107 ; --- wimp_save_fp_state_on_poll ---
108
109 EXPORT wimp_save_fp_state_on_poll
110 wimp_save_fp_state_on_poll
111 ROUT
112
113 LDR a1,=wimp__savefp ;Find the magic flag
114 MOV a2,#1 ;Store a TRUE value away
115 STR a2,[a1] ;Tuck it into my workspace
116 MOVS pc,lr ;Return to the caller
117
118 LTORG
119
120 ; --- wimp_corrupt_fp_state_on_poll ---
121
122 EXPORT wimp_corrupt_fp_state_on_poll
123 wimp_corrupt_fp_state_on_poll
124 ROUT
125
126 LDR a1,=wimp__savefp ;Find the magic flag
127 MOV a2,#0 ;Store a FALSE value away
128 STR a2,[a1] ;Tuck it into my workspace
129 MOVS pc,lr ;Return to the caller
130
131 LTORG
132
133 ; --- wimp__doPoll ---
134 ;
135 ; On entry: a1 == event mask
136 ; a2 == pointer to wimp poll block
137 ; a4 == pointer to poll word if bit 22 of a1 is set
138 ; On exit: a1 == reason code returned by Wimp_Poll
139 ; Other registers preserved
140 ;
141 ; Floating point status is preserved if a1 on entry has bit 24 set and the
142 ; floating point emulator or hardware is present. The floating point
143 ; registers preserved are f4-f7 and the FPSR.
144
145 wimp__doPoll ROUT
146
147 STMFD sp!,{v1-v3,lr}
148
149 MOV v2,#0 ;Don't restore FP state
150 TST a1,#1<<24 ;Does caller want FP saved?
151 BIC v3,a1,#1<<24 ;We're doing it, not the WIMP
152 BEQ %00 ;No -- skip this bit
153 SWI XFPEmulator_Version ;Is the FPE/FPA there?
154 MOVVC v2,#1 ;Yes -- set flag to restore
155 BLVC save_fp ;Save the FP state
156
157 00 MOV a1,v3 ;Restore event mask
158 SWI XWimp_Poll ;Do the SWI call
159 ORRVS v2,v2,#2 ;Set bit 1 of v2 if error
160
161 TST v2,#1 ;Is bit 0 set?
162 BLNE restore_fp ;Yes -- restore FP state
163 TST v2,#2 ;Was there an error?
164 LDMFD sp!,{v1-v3,lr} ;Restore all registers anyhow
165 BICEQS pc,lr,#V_flag ;No -- clear V flag
166 ORRS pc,lr,#V_flag ;Yes -- set V flag
167
168 LTORG
169
170 ; --- wimp__doPollIdle ---
171 ;
172 ; On entry: a1 == event mask
173 ; a2 == pointer to wimp poll block
174 ; a3 == earliest time to return with an idle event
175 ; a4 == pointer to poll word if bit 22 of a1 is set
176 ; On exit: a1 == reason code returned by Wimp_Poll
177 ; Other registers preserved
178 ;
179 ; Floating point status is preserved if a1 on entry has bit 24 set and the
180 ; floating point emulator or hardware is present. The floating point
181 ; registers preserved are f4-f7 and the FPSR.
182
183 wimp__doPollIdle ROUT
184
185 STMFD sp!,{v1-v3,lr}
186
187 MOV v2,#0 ;Don't restore FP state
188 TST a1,#1<<24 ;Does caller want FP saved?
189 BIC v3,a1,#1<<24 ;We're doing it, not the WIMP
190 BEQ %00 ;No -- skip this bit
191 SWI XFPEmulator_Version ;Is the FPE/FPA there?
192 MOVVC v2,#1 ;Yes -- set flag to restore
193 BLVC save_fp ;Save the FP state
194
195 00 MOV a1,v3 ;Restore event mask
196 SWI XWimp_PollIdle ;Do the SWI call
197 ORRVS v2,v2,#2 ;Set bit 1 of v2 if error
198
199 TST v2,#1 ;Is bit 0 set?
200 BLNE restore_fp ;Yes -- restore FP state
201 TST v2,#2 ;Was there an error?
202 LDMFD sp!,{v1-v3,lr} ;Restore all registers anyhow
203 BICEQS pc,lr,#V_flag ;No -- clear V flag
204 ORRS pc,lr,#V_flag ;Yes -- set V flag
205
206 LTORG
207
208 ; --- save_fp ---
209 ;
210 ; On entry: --
211 ; On exit: v1 corrupted
212
213 save_fp ROUT
214
215 RFS v1 ;Read the FP status word
216 STMFD sp!,{v1} ;Stack it
217 MOV v1,#0 ;We will zero the FPSR
218 WFS v1 ;Zero it
219 SUB sp,sp,#4*12 ;Leave space for 4 FP regs
220 STFE f4,[sp,#0*12] ;Stack F4
221 STFE f5,[sp,#1*12] ;Stack F5
222 STFE f6,[sp,#2*12] ;Stack F6
223 STFE f7,[sp,#3*12] ;Stack F7
224 MOVS pc,lr ;Return to caller
225
226 ; --- restore_fp ---
227 ;
228 ; On entry: --
229 ; On exit: v1 corrupted
230
231 restore_fp ROUT
232
233 MOV v1,#0 ;We will zero the FPSR
234 WFS v1 ;Zero it
235 LDFE f4,[sp,#0*12] ;Unstack F4
236 LDFE f5,[sp,#1*12] ;Unstack F5
237 LDFE f6,[sp,#2*12] ;Unstack F6
238 LDFE f7,[sp,#3*12] ;Unstack F7
239 ADD sp,sp,#4*12 ;Move stack ptr up past FP
240 LDMFD sp!,{v1} ;Restore FPSR
241 WFS v1 ;Write it to the FPSR
242 MOVS pc,lr ;Return to caller
243
244 ;----- Include the main wimp veneers ----------------------------------------
245
246 LNK s.wimp_main
The Straylight Source Distribution (obsolete software for RISC OS)