100 lines
3.4 KiB
C
100 lines
3.4 KiB
C
/*
|
|
* This file is part of the MicroPython project, http://micropython.org/
|
|
*
|
|
* The MIT License (MIT)
|
|
*
|
|
* Copyright (c) 2014 Paul Sokolovsky
|
|
*
|
|
* 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/runtime.h"
|
|
#include "py/stackctrl.h"
|
|
|
|
void mp_stack_ctrl_init(void) {
|
|
// Force routine to not be inlined. Better guarantee than MP_NOINLINE for -flto.
|
|
__asm volatile ("");
|
|
volatile int stack_dummy;
|
|
MP_STATE_THREAD(stack_top) = (char *)&stack_dummy;
|
|
}
|
|
|
|
void mp_stack_set_top(void *top) {
|
|
MP_STATE_THREAD(stack_top) = top;
|
|
}
|
|
|
|
mp_uint_t mp_stack_usage(void) {
|
|
// Assumes descending stack
|
|
// Force routine to not be inlined. Better guarantee than MP_NOINLINE for -flto.
|
|
__asm volatile ("");
|
|
volatile int stack_dummy;
|
|
return MP_STATE_THREAD(stack_top) - (char *)&stack_dummy;
|
|
}
|
|
|
|
#if MICROPY_STACK_CHECK
|
|
|
|
void mp_stack_set_limit(mp_uint_t limit) {
|
|
MP_STATE_THREAD(stack_limit) = limit;
|
|
}
|
|
|
|
void mp_stack_check(void) {
|
|
if (mp_stack_usage() >= MP_STATE_THREAD(stack_limit)) {
|
|
mp_raise_recursion_depth();
|
|
}
|
|
}
|
|
|
|
#endif // MICROPY_STACK_CHECK
|
|
|
|
#if MICROPY_MAX_STACK_USAGE
|
|
|
|
// Fill stack space with this unusual value.
|
|
const char MP_MAX_STACK_USAGE_SENTINEL_BYTE = 0xEE;
|
|
|
|
// Record absolute bottom (logical limit) of stack.
|
|
void mp_stack_set_bottom(void *stack_bottom) {
|
|
MP_STATE_THREAD(stack_bottom) = stack_bottom;
|
|
}
|
|
|
|
// Return the current frame pointer. This can be used as an
|
|
// approximation for the stack pointer of the _calling_ function.
|
|
// This routine must not be inlined. This method is
|
|
// architecture-independent, as opposed to using asm("sp") or similar.
|
|
//
|
|
// The stack_dummy approach used elsewhere in this file is not safe in
|
|
// all cases. That value may be below the actual top of the stack.
|
|
static void *approx_stack_pointer(void) {
|
|
__asm volatile ("");
|
|
return __builtin_frame_address(0);
|
|
}
|
|
|
|
// Fill stack space down toward the stack limit with a known unusual value.
|
|
void mp_stack_fill_with_sentinel(void) {
|
|
// Force routine to not be inlined. Better guarantee than MP_NOINLINE for -flto.
|
|
__asm volatile ("");
|
|
// Start filling stack just below the current stack frame.
|
|
// Continue until we've hit the bottom of the stack (lowest address,
|
|
// logical "ceiling" of stack).
|
|
char *p = (char *)approx_stack_pointer() - 1;
|
|
|
|
while (p >= MP_STATE_THREAD(stack_bottom)) {
|
|
*p-- = MP_MAX_STACK_USAGE_SENTINEL_BYTE;
|
|
}
|
|
}
|
|
|
|
#endif // MICROPY_MAX_STACK_USAGE
|