diff options
Diffstat (limited to 'py/nlrx86.c')
| -rw-r--r-- | py/nlrx86.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/py/nlrx86.c b/py/nlrx86.c new file mode 100644 index 000000000..4b178f46b --- /dev/null +++ b/py/nlrx86.c @@ -0,0 +1,106 @@ +/* + * 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" +#include "py/nlr.h" + +#if !MICROPY_NLR_SETJMP && defined(__i386__) + +#undef nlr_push + +// For reference, x86 callee save regs are: +// ebx, esi, edi, ebp, esp, eip + +#define NLR_OS_WINDOWS (defined(_WIN32) || defined(__CYGWIN__)) + +#if 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 + +unsigned int nlr_push(nlr_buf_t *nlr) { + (void)nlr; + + __asm volatile ( + "pop %ebp \n" // undo function's prelude + "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 +} + +__attribute__((used)) unsigned int nlr_push_tail(nlr_buf_t *nlr) { + nlr_buf_t **top = &MP_STATE_THREAD(nlr_top); + nlr->prev = *top; + *top = nlr; + return 0; // normal return +} + +void nlr_pop(void) { + nlr_buf_t **top = &MP_STATE_THREAD(nlr_top); + *top = (*top)->prev; +} + +NORETURN void nlr_jump(void *val) { + 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; + *top_ptr = top->prev; + + __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 + ); + + for (;;); // needed to silence compiler warning +} + +#endif // !MICROPY_NLR_SETJMP && defined(__i386__) |