libunwind.S revision 275771 
1/* Support functions for the unwinder.
2   Copyright (C) 2003, 2004, 2005  Free Software Foundation, Inc.
3   Contributed by Paul Brook
4
5   This file is free software; you can redistribute it and/or modify it
6   under the terms of the GNU General Public License as published by the
7   Free Software Foundation; either version 2, or (at your option) any
8   later version.
9
10   In addition to the permissions in the GNU General Public License, the
11   Free Software Foundation gives you unlimited permission to link the
12   compiled version of this file into combinations with other programs,
13   and to distribute those combinations without any restriction coming
14   from the use of this file.  (The General Public License restrictions
15   do apply in other respects; for example, they cover modification of
16   the file, and distribution when not linked into a combine
17   executable.)
18
19   This file is distributed in the hope that it will be useful, but
20   WITHOUT ANY WARRANTY; without even the implied warranty of
21   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
22   General Public License for more details.
23
24   You should have received a copy of the GNU General Public License
25   along with this program; see the file COPYING.  If not, write to
26   the Free Software Foundation, 51 Franklin Street, Fifth Floor,
27   Boston, MA 02110-1301, USA.  */
28
29#include <machine/acle-compat.h>
30
31/* Allow the use of VFP instructions */
32#if __ARM_ARCH >= 7
33.fpu	vfp
34#endif
35
36#ifndef __symbian__
37
38#include "lib1funcs.asm"
39
40.macro UNPREFIX name
41	.global SYM (\name)
42	EQUIV SYM (\name), SYM (__\name)
43.endm
44
45/* r0 points to a 16-word block.  Upload these values to the actual core
46   state.  */
47ARM_FUNC_START restore_core_regs
48	/* We must use sp as the base register when restoring sp.  Push the
49	   last 3 registers onto the top of the current stack to achieve
50	   this.  */
51	add r1, r0, #52
52	ldmia r1, {r3, r4, r5}  /* {sp, lr, pc}.  */
53#ifdef __INTERWORKING__
54	/* Restore pc into ip.  */
55	mov r2, r5
56	stmfd sp!, {r2, r3, r4}
57#else
58	stmfd sp!, {r3, r4, r5}
59#endif
60	/* Don't bother restoring ip.  */
61	ldmia r0, {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, sl, fp}
62	/* Pop the three registers we pushed earlier.  */
63#ifdef __INTERWORKING__
64	ldmfd sp, {ip, sp, lr}
65	bx ip
66#else
67	ldmfd sp, {sp, lr, pc}
68#endif
69	FUNC_END restore_core_regs
70	UNPREFIX restore_core_regs
71
72/* Load VFP registers d0-d15 from the address in r0.  */
73ARM_FUNC_START gnu_Unwind_Restore_VFP
74	/* Use the generic coprocessor form so that gas doesn't complain
75	   on soft-float targets.  */
76#if __ARM_ARCH >= 7
77	fldmiax r0, {d0-d15}
78#else
79	ldc   p11,cr0,[r0],{0x21} /* fldmiax r0, {d0-d15} */
80#endif
81	RET
82
83/* Store VFR regsters d0-d15 to the address in r0.  */
84ARM_FUNC_START gnu_Unwind_Save_VFP
85	/* Use the generic coprocessor form so that gas doesn't complain
86	   on soft-float targets.  */
87#if __ARM_ARCH >= 7
88	fstmiax r0, {d0-d15}
89#else
90	stc   p11,cr0,[r0],{0x21} /* fstmiax r0, {d0-d15} */
91#endif
92	RET
93
94/* Wrappers to save core registers, then call the real routine.   */
95
96.macro  UNWIND_WRAPPER name nargs
97	ARM_FUNC_START \name
98	/* Create a phase2_vrs structure.  */
99	/* Split reg push in two to ensure the correct value for sp.  */
100	stmfd sp!, {sp, lr, pc}
101	stmfd sp!, {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, sl, fp, ip}
102
103	/* Demand-save flags, plus an extra word for alignment.  */
104	mov r3, #0
105	stmfd sp!, {r2, r3}
106
107	/* Point r1 at the block.  Pass r[0..nargs) unchanged.  */
108	add r\nargs, sp, #4
109#if defined(__thumb__)
110	/* Switch back to thumb mode to avoid interworking hassle.  */
111	adr ip, .L1_\name
112	orr ip, ip, #1
113	bx ip
114	.thumb
115.L1_\name:
116	bl SYM (__gnu\name) __PLT__
117	ldr r3, [sp, #64]
118	add sp, #72
119	bx r3
120#else
121	bl SYM (__gnu\name) __PLT__
122	ldr lr, [sp, #64]
123	add sp, sp, #72
124	RET
125#endif
126	FUNC_END \name
127	UNPREFIX \name
128.endm
129
130UNWIND_WRAPPER _Unwind_RaiseException 1
131UNWIND_WRAPPER _Unwind_Resume 1
132UNWIND_WRAPPER _Unwind_Resume_or_Rethrow 1
133UNWIND_WRAPPER _Unwind_ForcedUnwind 3
134UNWIND_WRAPPER _Unwind_Backtrace 2
135
136#endif  /* ndef __symbian__ */
137