circuitpython/py/nlr.c

89 lines
3.2 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013-2023 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 !MICROPY_NLR_SETJMP
// When not using setjmp, nlr_push_tail is called from inline asm so needs special care
#if MICROPY_NLR_X86 && MICROPY_NLR_OS_WINDOWS
// On these 32-bit platforms make sure nlr_push_tail doesn't have a leading underscore
unsigned int nlr_push_tail(nlr_buf_t *nlr) asm ("nlr_push_tail");
#else
// LTO can't see inside inline asm functions so explicitly mark nlr_push_tail as used
__attribute__((used)) unsigned int nlr_push_tail(nlr_buf_t *nlr);
#endif
#endif
unsigned int nlr_push_tail(nlr_buf_t *nlr) {
nlr_buf_t **top = &MP_STATE_THREAD(nlr_top);
nlr->prev = *top;
MP_NLR_SAVE_PYSTACK(nlr);
*top = nlr;
return 0; // normal return
}
void nlr_pop(void) {
nlr_buf_t **top = &MP_STATE_THREAD(nlr_top);
*top = (*top)->prev;
}
void nlr_push_jump_callback(nlr_jump_callback_node_t *node, nlr_jump_callback_fun_t fun) {
nlr_jump_callback_node_t **top = &MP_STATE_THREAD(nlr_jump_callback_top);
node->prev = *top;
node->fun = fun;
*top = node;
}
void nlr_pop_jump_callback(bool run_callback) {
nlr_jump_callback_node_t **top = &MP_STATE_THREAD(nlr_jump_callback_top);
nlr_jump_callback_node_t *cur = *top;
*top = (*top)->prev;
if (run_callback) {
cur->fun(cur);
}
}
// This function pops and runs all callbacks that were registered after `nlr`
// was pushed (via nlr_push). It assumes:
// - a descending C stack,
// - that all nlr_jump_callback_node_t's in the linked-list pointed to by
// nlr_jump_callback_top are on the C stack
// It works by popping each node in turn until the next node is NULL or above
// the `nlr` pointer on the C stack (and so pushed before `nlr` was pushed).
void nlr_call_jump_callbacks(nlr_buf_t *nlr) {
nlr_jump_callback_node_t **top = &MP_STATE_THREAD(nlr_jump_callback_top);
while (*top != NULL && (void *)*top < (void *)nlr) {
nlr_pop_jump_callback(true);
}
}
#if MICROPY_ENABLE_VM_ABORT
NORETURN void nlr_jump_abort(void) {
MP_STATE_THREAD(nlr_top) = MP_STATE_VM(nlr_abort);
nlr_jump(NULL);
}
#endif