circuitpython/py/nlrx86.c
Scott Shawcroft b057fb8a4b
codeformat
2021-04-19 22:22:44 -07:00

107 lines
3.9 KiB
C

/*
* 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_X86) && MICROPY_NLR_X86
#undef nlr_push
// For reference, x86 callee save regs are:
// ebx, esi, edi, ebp, esp, eip
#if defined(MICROPY_NLR_OS_WINDOWS) && MICROPY_NLR_OS_WINDOWS
unsigned int nlr_push_tail(nlr_buf_t *nlr) asm ("nlr_push_tail");
#else
__attribute__((used)) unsigned int nlr_push_tail(nlr_buf_t *nlr);
#endif
#if !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 8
// Since gcc 8.0 the naked attribute is supported
#define USE_NAKED (1)
#define UNDO_PRELUDE (0)
#elif defined(__ZEPHYR__) || defined(__ANDROID__)
// Zephyr and Android use a different calling convention by default
#define USE_NAKED (0)
#define UNDO_PRELUDE (0)
#else
#define USE_NAKED (0)
#define UNDO_PRELUDE (1)
#endif
#if USE_NAKED
__attribute__((naked))
#endif
unsigned int nlr_push(nlr_buf_t *nlr) {
#if !USE_NAKED
(void)nlr;
#endif
__asm volatile (
#if UNDO_PRELUDE
"pop %ebp \n" // undo function's prelude
#endif
"mov 4(%esp), %edx \n" // load nlr_buf
"mov (%esp), %eax \n" // load return %eip
"mov %eax, 8(%edx) \n" // store %eip into nlr_buf
"mov %ebp, 12(%edx) \n" // store %ebp into nlr_buf
"mov %esp, 16(%edx) \n" // store %esp into nlr_buf
"mov %ebx, 20(%edx) \n" // store %ebx into nlr_buf
"mov %edi, 24(%edx) \n" // store %edi into nlr_buf
"mov %esi, 28(%edx) \n" // store %esi into nlr_buf
"jmp nlr_push_tail \n" // do the rest in C
);
#if !USE_NAKED
return 0; // needed to silence compiler warning
#endif
}
NORETURN void nlr_jump(void *val) {
MP_NLR_JUMP_HEAD(val, top)
__asm volatile (
"mov %0, %%edx \n" // %edx points to nlr_buf
"mov 28(%%edx), %%esi \n" // load saved %esi
"mov 24(%%edx), %%edi \n" // load saved %edi
"mov 20(%%edx), %%ebx \n" // load saved %ebx
"mov 16(%%edx), %%esp \n" // load saved %esp
"mov 12(%%edx), %%ebp \n" // load saved %ebp
"mov 8(%%edx), %%eax \n" // load saved %eip
"mov %%eax, (%%esp) \n" // store saved %eip to stack
"xor %%eax, %%eax \n" // clear return register
"inc %%al \n" // increase to make 1, non-local return
"ret \n" // return
: // output operands
: "r" (top) // input operands
: // clobbered registers
);
MP_UNREACHABLE
}
#endif // MICROPY_NLR_X86