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Diffstat (limited to 'circuitpython/py/nlr.h')
| -rw-r--r-- | circuitpython/py/nlr.h | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/circuitpython/py/nlr.h b/circuitpython/py/nlr.h new file mode 100644 index 0000000..1fb51f3 --- /dev/null +++ b/circuitpython/py/nlr.h @@ -0,0 +1,190 @@ +/* + * This file is part of the MicroPython project, http://micropython.org/ + * + * The MIT License (MIT) + * + * SPDX-FileCopyrightText: Copyright (c) 2013, 2014 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. + */ +#ifndef MICROPY_INCLUDED_PY_NLR_H +#define MICROPY_INCLUDED_PY_NLR_H + +// non-local return +// exception handling, basically a stack of setjmp/longjmp buffers + +#include <limits.h> +#include <assert.h> + +#include "py/mpconfig.h" + +#define MICROPY_NLR_NUM_REGS_X86 (6) +#define MICROPY_NLR_NUM_REGS_X64 (8) +#define MICROPY_NLR_NUM_REGS_X64_WIN (10) +#define MICROPY_NLR_NUM_REGS_ARM_THUMB (10) +#define MICROPY_NLR_NUM_REGS_ARM_THUMB_FP (10 + 6) +#define MICROPY_NLR_NUM_REGS_AARCH64 (13) +#define MICROPY_NLR_NUM_REGS_XTENSA (10) +#define MICROPY_NLR_NUM_REGS_XTENSAWIN (17) + +// *FORMAT-OFF* + +// If MICROPY_NLR_SETJMP is not enabled then auto-detect the machine arch +#if !defined(MICROPY_NLR_SETJMP) || !MICROPY_NLR_SETJMP +// A lot of nlr-related things need different treatment on Windows +#if defined(_WIN32) || defined(__CYGWIN__) +#define MICROPY_NLR_OS_WINDOWS 1 +#else +#define MICROPY_NLR_OS_WINDOWS 0 +#endif +#if defined(__i386__) + #define MICROPY_NLR_SETJMP (0) + #define MICROPY_NLR_X86 (1) + #define MICROPY_NLR_NUM_REGS (MICROPY_NLR_NUM_REGS_X86) +#elif defined(__x86_64__) + #define MICROPY_NLR_SETJMP (0) + #define MICROPY_NLR_X64 (1) + #if MICROPY_NLR_OS_WINDOWS + #define MICROPY_NLR_NUM_REGS (MICROPY_NLR_NUM_REGS_X64_WIN) + #else + #define MICROPY_NLR_NUM_REGS (MICROPY_NLR_NUM_REGS_X64) + #endif +#elif defined(__thumb2__) || defined(__thumb__) || defined(__arm__) + #define MICROPY_NLR_SETJMP (0) + #define MICROPY_NLR_THUMB (1) + #if defined(__SOFTFP__) + #define MICROPY_NLR_NUM_REGS (MICROPY_NLR_NUM_REGS_ARM_THUMB) + #else + // With hardware FP registers s16-s31 are callee save so in principle + // should be saved and restored by the NLR code. gcc only uses s16-s21 + // so only save/restore those as an optimisation. + #define MICROPY_NLR_NUM_REGS (MICROPY_NLR_NUM_REGS_ARM_THUMB_FP) + #endif +#elif defined(__aarch64__) + #define MICROPY_NLR_AARCH64 (1) + #define MICROPY_NLR_NUM_REGS (MICROPY_NLR_NUM_REGS_AARCH64) +#elif defined(__xtensa__) + #define MICROPY_NLR_SETJMP (0) + #define MICROPY_NLR_XTENSA (1) + #define MICROPY_NLR_NUM_REGS (MICROPY_NLR_NUM_REGS_XTENSA) +#elif defined(__powerpc__) + #define MICROPY_NLR_SETJMP (0) + #define MICROPY_NLR_POWERPC (1) + // this could be less but using 128 for safety + #define MICROPY_NLR_NUM_REGS (128) +#else + #define MICROPY_NLR_SETJMP (1) +// #warning "No native NLR support for this arch, using setjmp implementation" +#endif +#endif + +// If MICROPY_NLR_SETJMP is not defined above - define/disable it here +#if !defined(MICROPY_NLR_SETJMP) + #define MICROPY_NLR_SETJMP (0) +#endif + +// *FORMAT-ON* + +#if MICROPY_NLR_SETJMP +#include <setjmp.h> +#endif + +typedef struct _nlr_buf_t nlr_buf_t; +struct _nlr_buf_t { + // the entries here must all be machine word size + nlr_buf_t *prev; + void *ret_val; // always a concrete object (an exception instance) + + #if MICROPY_NLR_SETJMP + jmp_buf jmpbuf; + #else + void *regs[MICROPY_NLR_NUM_REGS]; + #endif + + #if MICROPY_ENABLE_PYSTACK + void *pystack; + #endif +}; + +// Helper macros to save/restore the pystack state +#if MICROPY_ENABLE_PYSTACK +#define MP_NLR_SAVE_PYSTACK(nlr_buf) (nlr_buf)->pystack = MP_STATE_THREAD(pystack_cur) +#define MP_NLR_RESTORE_PYSTACK(nlr_buf) MP_STATE_THREAD(pystack_cur) = (nlr_buf)->pystack +#else +#define MP_NLR_SAVE_PYSTACK(nlr_buf) (void)nlr_buf +#define MP_NLR_RESTORE_PYSTACK(nlr_buf) (void)nlr_buf +#endif + +// Helper macro to use at the start of a specific nlr_jump implementation +#define MP_NLR_JUMP_HEAD(val, top) \ + nlr_buf_t **_top_ptr = &MP_STATE_THREAD(nlr_top); \ + nlr_buf_t *top = *_top_ptr; \ + if (top == NULL) { \ + nlr_jump_fail(val); \ + } \ + top->ret_val = val; \ + MP_NLR_RESTORE_PYSTACK(top); \ + *_top_ptr = top->prev; \ + +#if MICROPY_NLR_SETJMP +// nlr_push() must be defined as a macro, because "The stack context will be +// invalidated if the function which called setjmp() returns." +// For this case it is safe to call nlr_push_tail() first. +#define nlr_push(buf) (nlr_push_tail(buf), setjmp((buf)->jmpbuf)) +#else +unsigned int nlr_push(nlr_buf_t *); +#endif + +unsigned int nlr_push_tail(nlr_buf_t *top); +void nlr_pop(void); +NORETURN void nlr_jump(void *val); + +// This must be implemented by a port. It's called by nlr_jump +// if no nlr buf has been pushed. It must not return, but rather +// should bail out with a fatal error. +NORETURN void nlr_jump_fail(void *val); + +// use nlr_raise instead of nlr_jump so that debugging is easier +#ifndef MICROPY_DEBUG_NLR +#define nlr_raise(val) nlr_jump(MP_OBJ_TO_PTR(val)) +#else +#include "mpstate.h" +#define nlr_raise(val) \ + do { \ + /*printf("nlr_raise: nlr_top=%p\n", MP_STATE_THREAD(nlr_top)); \ + fflush(stdout);*/ \ + void *_val = MP_OBJ_TO_PTR(val); \ + assert(_val != NULL); \ + assert(mp_obj_is_exception_instance(val)); \ + nlr_jump(_val); \ + } while (0) + +#if !MICROPY_NLR_SETJMP +#define nlr_push(val) \ + assert(MP_STATE_THREAD(nlr_top) != val),nlr_push(val) + +/* +#define nlr_push(val) \ + printf("nlr_push: before: nlr_top=%p, val=%p\n", MP_STATE_THREAD(nlr_top), val),assert(MP_STATE_THREAD(nlr_top) != val),nlr_push(val) +*/ +#endif + +#endif + +#endif // MICROPY_INCLUDED_PY_NLR_H |