1/*
2 * This file is part of the MicroPython project, http://micropython.org/
3 *
4 * The MIT License (MIT)
5 *
6 * Copyright (c) 2013-2017 Damien P. George
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26
27#include "py/mpstate.h"
28
29#if MICROPY_NLR_THUMB
30
31#undef nlr_push
32
33// We only need the functions here if we are on arm/thumb, and we are not
34// using setjmp/longjmp.
35//
36// For reference, arm/thumb callee save regs are:
37// r4-r11, r13=sp
38
39__attribute__((naked)) unsigned int nlr_push(nlr_buf_t *nlr) {
40
41 __asm volatile (
42 "str r4, [r0, #12] \n" // store r4 into nlr_buf
43 "str r5, [r0, #16] \n" // store r5 into nlr_buf
44 "str r6, [r0, #20] \n" // store r6 into nlr_buf
45 "str r7, [r0, #24] \n" // store r7 into nlr_buf
46
47 #if !defined(__thumb2__)
48 "mov r1, r8 \n"
49 "str r1, [r0, #28] \n" // store r8 into nlr_buf
50 "mov r1, r9 \n"
51 "str r1, [r0, #32] \n" // store r9 into nlr_buf
52 "mov r1, r10 \n"
53 "str r1, [r0, #36] \n" // store r10 into nlr_buf
54 "mov r1, r11 \n"
55 "str r1, [r0, #40] \n" // store r11 into nlr_buf
56 "mov r1, r13 \n"
57 "str r1, [r0, #44] \n" // store r13=sp into nlr_buf
58 "mov r1, lr \n"
59 "str r1, [r0, #8] \n" // store lr into nlr_buf
60 #else
61 "str r8, [r0, #28] \n" // store r8 into nlr_buf
62 "str r9, [r0, #32] \n" // store r9 into nlr_buf
63 "str r10, [r0, #36] \n" // store r10 into nlr_buf
64 "str r11, [r0, #40] \n" // store r11 into nlr_buf
65 "str r13, [r0, #44] \n" // store r13=sp into nlr_buf
66 #if MICROPY_NLR_NUM_REGS == 16
67 "vstr d8, [r0, #48] \n" // store s16-s17 into nlr_buf
68 "vstr d9, [r0, #56] \n" // store s18-s19 into nlr_buf
69 "vstr d10, [r0, #64] \n" // store s20-s21 into nlr_buf
70 #endif
71 "str lr, [r0, #8] \n" // store lr into nlr_buf
72 #endif
73
74 #if !defined(__thumb2__)
75 "ldr r1, nlr_push_tail_var \n"
76 "bx r1 \n" // do the rest in C
77 ".align 2 \n"
78 "nlr_push_tail_var: .word nlr_push_tail \n"
79 #else
80 #if defined(__APPLE__) || defined(__MACH__)
81 "b _nlr_push_tail \n" // do the rest in C
82 #else
83 "b nlr_push_tail \n" // do the rest in C
84 #endif
85 #endif
86 );
87
88 #if !defined(__clang__) && defined(__GNUC__) && (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 8))
89 // Older versions of gcc give an error when naked functions don't return a value
90 // Additionally exclude Clang as it also defines __GNUC__ but doesn't need this statement
91 return 0;
92 #endif
93}
94
95NORETURN void nlr_jump(void *val) {
96 MP_NLR_JUMP_HEAD(val, top)
97
98 __asm volatile (
99 "mov r0, %0 \n" // r0 points to nlr_buf
100 "ldr r4, [r0, #12] \n" // load r4 from nlr_buf
101 "ldr r5, [r0, #16] \n" // load r5 from nlr_buf
102 "ldr r6, [r0, #20] \n" // load r6 from nlr_buf
103 "ldr r7, [r0, #24] \n" // load r7 from nlr_buf
104
105 #if !defined(__thumb2__)
106 "ldr r1, [r0, #28] \n" // load r8 from nlr_buf
107 "mov r8, r1 \n"
108 "ldr r1, [r0, #32] \n" // load r9 from nlr_buf
109 "mov r9, r1 \n"
110 "ldr r1, [r0, #36] \n" // load r10 from nlr_buf
111 "mov r10, r1 \n"
112 "ldr r1, [r0, #40] \n" // load r11 from nlr_buf
113 "mov r11, r1 \n"
114 "ldr r1, [r0, #44] \n" // load r13=sp from nlr_buf
115 "mov r13, r1 \n"
116 "ldr r1, [r0, #8] \n" // load lr from nlr_buf
117 "mov lr, r1 \n"
118 #else
119 "ldr r8, [r0, #28] \n" // load r8 from nlr_buf
120 "ldr r9, [r0, #32] \n" // load r9 from nlr_buf
121 "ldr r10, [r0, #36] \n" // load r10 from nlr_buf
122 "ldr r11, [r0, #40] \n" // load r11 from nlr_buf
123 "ldr r13, [r0, #44] \n" // load r13=sp from nlr_buf
124 #if MICROPY_NLR_NUM_REGS == 16
125 "vldr d8, [r0, #48] \n" // load s16-s17 from nlr_buf
126 "vldr d9, [r0, #56] \n" // load s18-s19 from nlr_buf
127 "vldr d10, [r0, #64] \n" // load s20-s21 from nlr_buf
128 #endif
129 "ldr lr, [r0, #8] \n" // load lr from nlr_buf
130 #endif
131 "movs r0, #1 \n" // return 1, non-local return
132 "bx lr \n" // return
133 : // output operands
134 : "r" (top) // input operands
135 : // clobbered registers
136 );
137
138 MP_UNREACHABLE
139}
140
141#endif // MICROPY_NLR_THUMB
142