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| 1 | +/* |
| 2 | + * This file is part of the MicroPython project, http://micropython.org/ |
| 3 | + * |
| 4 | + * The MIT License (MIT) |
| 5 | + * |
| 6 | + * Copyright (c) 2021 Yonatan Goldschmidt |
| 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" // needed for NLR defs |
| 28 | + |
| 29 | +#if MICROPY_NLR_AARCH64 |
| 30 | + |
| 31 | +// AArch64 callee-saved registers are x19-x29. |
| 32 | +// https://en.wikipedia.org/wiki/Calling_convention#ARM_(A64) |
| 33 | + |
| 34 | +// Implemented purely as inline assembly; inside a function, we have to deal with undoing the prologue, restoring |
| 35 | +// SP and LR. This way, we don't. |
| 36 | +__asm( |
| 37 | + "nlr_push: \n" |
| 38 | + ".global nlr_push \n" |
| 39 | + "mov x9, sp \n" |
| 40 | + "stp lr, x9, [x0, #16]\n" // 16 == offsetof(nlr_buf_t, regs) |
| 41 | + "stp x19, x20, [x0, #32]\n" |
| 42 | + "stp x21, x22, [x0, #48]\n" |
| 43 | + "stp x23, x24, [x0, #64]\n" |
| 44 | + "stp x25, x26, [x0, #80]\n" |
| 45 | + "stp x27, x28, [x0, #96]\n" |
| 46 | + "str x29, [x0, #112]\n" |
| 47 | + "b nlr_push_tail \n" // do the rest in C |
| 48 | + ); |
| 49 | + |
| 50 | +NORETURN void nlr_jump(void *val) { |
| 51 | + MP_NLR_JUMP_HEAD(val, top) |
| 52 | + |
| 53 | + MP_STATIC_ASSERT(offsetof(nlr_buf_t, regs) == 16); // asm assumes it |
| 54 | + |
| 55 | + __asm volatile ( |
| 56 | + "ldr x29, [%0, #112]\n" |
| 57 | + "ldp x27, x28, [%0, #96]\n" |
| 58 | + "ldp x25, x26, [%0, #80]\n" |
| 59 | + "ldp x23, x24, [%0, #64]\n" |
| 60 | + "ldp x21, x22, [%0, #48]\n" |
| 61 | + "ldp x19, x20, [%0, #32]\n" |
| 62 | + "ldp lr, x9, [%0, #16]\n" // 16 == offsetof(nlr_buf_t, regs) |
| 63 | + "mov sp, x9 \n" |
| 64 | + "mov x0, #1 \n" // non-local return |
| 65 | + "ret \n" |
| 66 | + : |
| 67 | + : "r" (top) |
| 68 | + : |
| 69 | + ); |
| 70 | + |
| 71 | + MP_UNREACHABLE |
| 72 | +} |
| 73 | + |
| 74 | +#endif // MICROPY_NLR_AARCH64 |
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