PythonExtra/py/nlrx86.c

81 lines
3.1 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* 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 MICROPY_NLR_X86
#undef nlr_push
// For reference, x86 callee save regs are:
// ebx, esi, edi, ebp, esp, eip
unsigned int nlr_push(nlr_buf_t *nlr) {
(void)nlr;
__asm volatile (
// Check for Zephyr, which uses a different calling convention
// by default.
// TODE: Better support for various x86 calling conventions
// (unfortunately, __attribute__((naked)) is not supported on x86).
#if !(defined(__ZEPHYR__) || defined(__ANDROID__))
"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
);
return 0; // needed to silence compiler warning
}
NORETURN void nlr_jump_tail(nlr_buf_t *top) {
(void)top;
__asm volatile (
"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
);
for (;;); // needed to silence compiler warning
}
#endif // MICROPY_NLR_X86