aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/s390/s390-32/dl-trampoline.h
blob: 086449f0f2978ba08065f2f62d394724408a91cf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
/* PLT trampolines.  s390 version.
   Copyright (C) 2016 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

/* This code is used in dl-runtime.c to call the `fixup' function
   and then redirect to the address it returns.  */

/* The PLT stubs will call _dl_runtime_resolve/_dl_runtime_profile
 * with the following linkage:
 *   r2 - r6 : parameter registers
 *   f0, f2 : floating point parameter registers
 *   v24, v26, v28, v30, v25, v27, v29, v31 : vector parameter registers
 *   24(r15), 28(r15) : PLT arguments PLT1, PLT2
 *   96(r15) : additional stack parameters
 * The normal clobber rules for function calls apply:
 *   r0 - r5 : call clobbered
 *   r6 - r13 :	call saved
 *   r14 : return address (call clobbered)
 *   r15 : stack pointer (call saved)
 *   f4, f6 : call saved
 *   f0 - f3, f5, f7 - f15 : call clobbered
 *   v0 - v3, v5, v7 - v15 : bytes 0-7 overlap with fprs: call clobbered
               bytes 8-15: call clobbered
 *   v4, v6 : bytes 0-7 overlap with f4, f6: call saved
              bytes 8-15: call clobbered
 *   v16 - v31 : call clobbered
 */


	.globl _dl_runtime_resolve
	.type _dl_runtime_resolve, @function
	cfi_startproc
	.align 16
_dl_runtime_resolve:
	stm    %r2,%r5,32(%r15)		# save registers
	cfi_offset (r2, -64)
	cfi_offset (r3, -60)
	cfi_offset (r4, -56)
	cfi_offset (r5, -52)
	std    %f0,56(%r15)
	cfi_offset (f0, -40)
	std    %f2,64(%r15)
	cfi_offset (f2, -32)
	st     %r14,8(%r15)
	cfi_offset (r14, -88)
	lr     %r0,%r15
	lm     %r2,%r3,24(%r15)		# load args saved by PLT
#ifdef RESTORE_VRS
	ahi    %r15,-224		# create stack frame
	cfi_adjust_cfa_offset (224)
	.machine push
	.machine "z13"
	.machinemode "zarch_nohighgprs"
	vstm   %v24,%v31,96(%r15)	# store call-clobbered vr arguments
	cfi_offset (v24, -224)
	cfi_offset (v25, -208)
	cfi_offset (v26, -192)
	cfi_offset (v27, -176)
	cfi_offset (v28, -160)
	cfi_offset (v29, -144)
	cfi_offset (v30, -128)
	cfi_offset (v31, -112)
	.machine pop
#else
	ahi    %r15,-96			# create stack frame
	cfi_adjust_cfa_offset (96)
#endif
	st     %r0,0(%r15)		# write backchain
	basr   %r1,0
0:	l      %r14,1f-0b(%r1)
	bas    %r14,0(%r14,%r1)		# call _dl_fixup
	lr     %r1,%r2			# function addr returned in r2
#ifdef RESTORE_VRS
	.machine push
	.machine "z13"
	.machinemode "zarch_nohighgprs"
	vlm    %v24,%v31,96(%r15)	# restore vector registers
	.machine pop
	ahi   %r15,224			# remove stack frame
	cfi_adjust_cfa_offset (-224)
#else
	ahi    %r15,96			# remove stack frame
	cfi_adjust_cfa_offset (-96)
#endif
	l      %r14,8(15)		# restore registers
	ld     %f0,56(%r15)
	ld     %f2,64(%r15)
	lm     %r2,%r5,32(%r15)
	br     %r1
1:	.long  _dl_fixup - 0b
	cfi_endproc
	.size _dl_runtime_resolve, .-_dl_runtime_resolve


#ifndef PROF
	.globl _dl_runtime_profile
	.type _dl_runtime_profile, @function
	cfi_startproc
	.align 16
_dl_runtime_profile:
	st     %r12,12(%r15)		# r12 is used as backup of r15
	cfi_offset (r12, -84)
	st     %r14,16(%r15)
	cfi_offset (r14, -80)
	lr     %r12,%r15		# backup stack pointer
	cfi_def_cfa_register (12)
	ahi    %r15,-264		# create stack frame:
					# 96 + sizeof(La_s390_32_regs)
	st     %r12,0(%r15)		# save backchain

	stm    %r2,%r6,96(%r15)		# save registers
	cfi_offset (r2, -264)		# + r6 needed as arg for
	cfi_offset (r3, -260)		#  _dl_profile_fixup
	cfi_offset (r4, -256)
	cfi_offset (r5, -252)
	cfi_offset (r6, -248)
	std    %f0,120(%r15)
	cfi_offset (f0, -240)
	std    %f2,128(%r15)
	cfi_offset (f2, -232)
#ifdef RESTORE_VRS
	.machine push
	.machine "z13"
	.machinemode "zarch_nohighgprs"
	vstm   %v24,%v31,136(%r15)	# store call-clobbered vr arguments
	cfi_offset (v24, -224)
	cfi_offset (v25, -208)
	cfi_offset (v26, -192)
	cfi_offset (v27, -176)
	cfi_offset (v28, -160)
	cfi_offset (v29, -144)
	cfi_offset (v30, -128)
	cfi_offset (v31, -112)
	.machine pop
#endif

	lm     %r2,%r3,24(%r12)		# load arguments saved by PLT
	lr     %r4,%r14			# return address as third parameter
	basr   %r1,0
0:	l      %r14,6f-0b(%r1)
	la     %r5,96(%r15)		# pointer to struct La_s390_32_regs
	la     %r6,20(%r12)		# long int * framesize
	bas    %r14,0(%r14,%r1)		# call resolver
	lr     %r1,%r2			# function addr returned in r2
	ld     %f0,120(%r15)		# restore call-clobbered arg fprs
	ld     %f2,128(%r15)
#ifdef RESTORE_VRS
	.machine push
	.machine "z13"
	.machinemode "zarch_nohighgprs"
	vlm    %v24,%v31,136(%r15)	# restore call-clobbered arg vrs
	.machine pop
#endif
	icm    %r0,15,20(%r12)		# load & test framesize
	jnm    2f

	lm     %r2,%r6,96(%r15)		# framesize < 0 means no pltexit call
					# so we can do a tail call without
					# copying the arg overflow area
	lr     %r15,%r12		# remove stack frame
	cfi_def_cfa_register (15)
	l      %r14,16(%r15)		# restore registers
	l      %r12,12(%r15)
	br     %r1			# tail-call to the resolved function

	cfi_def_cfa_register (12)
2:	la     %r4,96(%r15)		# pointer to struct La_s390_32_regs
	st     %r4,32(%r12)
	jz     4f			# framesize == 0 ?
	ahi    %r0,7			# align framesize to 8
	lhi    %r2,-8
	nr     %r0,%r2
	slr    %r15,%r0			# make room for framesize bytes
	st     %r12,0(%r15)		# save backchain
	la     %r2,96(%r15)
	la     %r3,96(%r12)
	srl    %r0,3
3:	mvc    0(8,%r2),0(%r3)		# copy additional parameters
	la     %r2,8(%r2)
	la     %r3,8(%r3)
	brct   %r0,3b
4:	lm     %r2,%r6,0(%r4)		# load register parameters
	basr   %r14,%r1			# call resolved function
	stm    %r2,%r3,40(%r12)		# store return values r2, r3, f0
	std    %f0,48(%r12)		# to struct La_s390_32_retval
#ifdef RESTORE_VRS
	.machine push
	.machine "z13"
	vst    %v24,56(%r12)		# store return value v24
	.machine pop
#endif
	lm     %r2,%r4,24(%r12)		# r2, r3: load arguments saved by PLT
					# r4: pointer to struct La_s390_32_regs
	basr   %r1,0
5:	l      %r14,7f-5b(%r1)
	la     %r5,40(%r12)		# pointer to struct La_s390_32_retval
	bas    %r14,0(%r14,%r1)		# call _dl_call_pltexit

	lr     %r15,%r12		# remove stack frame
	cfi_def_cfa_register (15)
	l      %r14,16(%r15)		# restore registers
	l      %r12,12(%r15)
	lm     %r2,%r3,40(%r15)		# restore return values
	ld     %f0,48(%r15)
#ifdef RESTORE_VRS
	.machine push
	.machine "z13"
	vl    %v24,56(%r15)		# restore return value v24
	.machine pop
#endif
	br     %r14

6:	.long  _dl_profile_fixup - 0b
7:	.long  _dl_call_pltexit - 5b
	cfi_endproc
	.size _dl_runtime_profile, .-_dl_runtime_profile
#endif