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Diffstat (limited to 'circuitpython/py/nlrthumb.c')
| -rw-r--r-- | circuitpython/py/nlrthumb.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/circuitpython/py/nlrthumb.c b/circuitpython/py/nlrthumb.c new file mode 100644 index 0000000..30f9f2c --- /dev/null +++ b/circuitpython/py/nlrthumb.c @@ -0,0 +1,141 @@ +/* + * This file is part of the MicroPython project, http://micropython.org/ + * + * The MIT License (MIT) + * + * SPDX-FileCopyrightText: Copyright (c) 2013-2017 Damien P. George + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include "py/mpstate.h" + +#if defined(MICROPY_NLR_THUMB) && MICROPY_NLR_THUMB + +#undef nlr_push + +// We only need the functions here if we are on arm/thumb, and we are not +// using setjmp/longjmp. +// +// For reference, arm/thumb callee save regs are: +// r4-r11, r13=sp + +__attribute__((naked)) unsigned int nlr_push(nlr_buf_t *nlr) { + + __asm volatile ( + "str r4, [r0, #12] \n" // store r4 into nlr_buf + "str r5, [r0, #16] \n" // store r5 into nlr_buf + "str r6, [r0, #20] \n" // store r6 into nlr_buf + "str r7, [r0, #24] \n" // store r7 into nlr_buf + + #if !defined(__thumb2__) + "mov r1, r8 \n" + "str r1, [r0, #28] \n" // store r8 into nlr_buf + "mov r1, r9 \n" + "str r1, [r0, #32] \n" // store r9 into nlr_buf + "mov r1, r10 \n" + "str r1, [r0, #36] \n" // store r10 into nlr_buf + "mov r1, r11 \n" + "str r1, [r0, #40] \n" // store r11 into nlr_buf + "mov r1, r13 \n" + "str r1, [r0, #44] \n" // store r13=sp into nlr_buf + "mov r1, lr \n" + "str r1, [r0, #8] \n" // store lr into nlr_buf + #else + "str r8, [r0, #28] \n" // store r8 into nlr_buf + "str r9, [r0, #32] \n" // store r9 into nlr_buf + "str r10, [r0, #36] \n" // store r10 into nlr_buf + "str r11, [r0, #40] \n" // store r11 into nlr_buf + "str r13, [r0, #44] \n" // store r13=sp into nlr_buf + #if MICROPY_NLR_NUM_REGS == 16 + "vstr d8, [r0, #48] \n" // store s16-s17 into nlr_buf + "vstr d9, [r0, #56] \n" // store s18-s19 into nlr_buf + "vstr d10, [r0, #64] \n" // store s20-s21 into nlr_buf + #endif + "str lr, [r0, #8] \n" // store lr into nlr_buf + #endif + + #if !defined(__thumb2__) + "ldr r1, nlr_push_tail_var \n" + "bx r1 \n" // do the rest in C + ".align 2 \n" + "nlr_push_tail_var: .word nlr_push_tail \n" + #else + #if defined(__APPLE__) || defined(__MACH__) + "b _nlr_push_tail \n" // do the rest in C + #else + "b nlr_push_tail \n" // do the rest in C + #endif + #endif + ); + + #if !defined(__clang__) && defined(__GNUC__) && (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 8)) + // Older versions of gcc give an error when naked functions don't return a value + // Additionally exclude Clang as it also defines __GNUC__ but doesn't need this statement + return 0; + #endif +} + +NORETURN void nlr_jump(void *val) { + MP_NLR_JUMP_HEAD(val, top) + + __asm volatile ( + "mov r0, %0 \n" // r0 points to nlr_buf + "ldr r4, [r0, #12] \n" // load r4 from nlr_buf + "ldr r5, [r0, #16] \n" // load r5 from nlr_buf + "ldr r6, [r0, #20] \n" // load r6 from nlr_buf + "ldr r7, [r0, #24] \n" // load r7 from nlr_buf + + #if !defined(__thumb2__) + "ldr r1, [r0, #28] \n" // load r8 from nlr_buf + "mov r8, r1 \n" + "ldr r1, [r0, #32] \n" // load r9 from nlr_buf + "mov r9, r1 \n" + "ldr r1, [r0, #36] \n" // load r10 from nlr_buf + "mov r10, r1 \n" + "ldr r1, [r0, #40] \n" // load r11 from nlr_buf + "mov r11, r1 \n" + "ldr r1, [r0, #44] \n" // load r13=sp from nlr_buf + "mov r13, r1 \n" + "ldr r1, [r0, #8] \n" // load lr from nlr_buf + "mov lr, r1 \n" + #else + "ldr r8, [r0, #28] \n" // load r8 from nlr_buf + "ldr r9, [r0, #32] \n" // load r9 from nlr_buf + "ldr r10, [r0, #36] \n" // load r10 from nlr_buf + "ldr r11, [r0, #40] \n" // load r11 from nlr_buf + "ldr r13, [r0, #44] \n" // load r13=sp from nlr_buf + #if MICROPY_NLR_NUM_REGS == 16 + "vldr d8, [r0, #48] \n" // load s16-s17 from nlr_buf + "vldr d9, [r0, #56] \n" // load s18-s19 from nlr_buf + "vldr d10, [r0, #64] \n" // load s20-s21 from nlr_buf + #endif + "ldr lr, [r0, #8] \n" // load lr from nlr_buf + #endif + "movs r0, #1 \n" // return 1, non-local return + "bx lr \n" // return + : // output operands + : "r" (top) // input operands + : // clobbered registers + ); + + MP_UNREACHABLE +} + +#endif // MICROPY_NLR_THUMB |