micropython/shared/runtime/gchelper_generic.c

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5.8 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* 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.
*/
#include <stdio.h>
#include "py/mpstate.h"
#include "py/gc.h"
#include "shared/runtime/gchelper.h"
#if MICROPY_ENABLE_GC
// Even if we have specific support for an architecture, it is
// possible to force use of setjmp-based implementation.
#if !MICROPY_GCREGS_SETJMP
// We capture here callee-save registers, i.e. ones which may contain
// interesting values held there by our callers. It doesn't make sense
// to capture caller-saved registers, because they, well, put on the
// stack already by the caller.
#if defined(__x86_64__)
STATIC void gc_helper_get_regs(gc_helper_regs_t arr) {
register long rbx asm ("rbx");
register long rbp asm ("rbp");
register long r12 asm ("r12");
register long r13 asm ("r13");
register long r14 asm ("r14");
register long r15 asm ("r15");
#ifdef __clang__
// TODO:
// This is dirty workaround for Clang. It tries to get around
// uncompliant (wrt to GCC) behavior of handling register variables.
// Application of this patch here is random, and done only to unbreak
// MacOS build. Better, cross-arch ways to deal with Clang issues should
// be found.
asm ("" : "=r" (rbx));
asm ("" : "=r" (rbp));
asm ("" : "=r" (r12));
asm ("" : "=r" (r13));
asm ("" : "=r" (r14));
asm ("" : "=r" (r15));
#endif
arr[0] = rbx;
arr[1] = rbp;
arr[2] = r12;
arr[3] = r13;
arr[4] = r14;
arr[5] = r15;
}
#elif defined(__i386__)
STATIC void gc_helper_get_regs(gc_helper_regs_t arr) {
register long ebx asm ("ebx");
register long esi asm ("esi");
register long edi asm ("edi");
register long ebp asm ("ebp");
#ifdef __clang__
// TODO:
// This is dirty workaround for Clang. It tries to get around
// uncompliant (wrt to GCC) behavior of handling register variables.
// Application of this patch here is random, and done only to unbreak
// MacOS build. Better, cross-arch ways to deal with Clang issues should
// be found.
asm ("" : "=r" (ebx));
asm ("" : "=r" (esi));
asm ("" : "=r" (edi));
asm ("" : "=r" (ebp));
#endif
arr[0] = ebx;
arr[1] = esi;
arr[2] = edi;
arr[3] = ebp;
}
#elif defined(__thumb2__) || defined(__thumb__) || defined(__arm__)
// Fallback implementation, prefer gchelper_m0.s or gchelper_m3.s
STATIC void gc_helper_get_regs(gc_helper_regs_t arr) {
register long r4 asm ("r4");
register long r5 asm ("r5");
register long r6 asm ("r6");
register long r7 asm ("r7");
register long r8 asm ("r8");
register long r9 asm ("r9");
register long r10 asm ("r10");
register long r11 asm ("r11");
register long r12 asm ("r12");
register long r13 asm ("r13");
arr[0] = r4;
arr[1] = r5;
arr[2] = r6;
arr[3] = r7;
arr[4] = r8;
arr[5] = r9;
arr[6] = r10;
arr[7] = r11;
arr[8] = r12;
arr[9] = r13;
}
#elif defined(__aarch64__)
STATIC void gc_helper_get_regs(gc_helper_regs_t arr) {
const register long x19 asm ("x19");
const register long x20 asm ("x20");
const register long x21 asm ("x21");
const register long x22 asm ("x22");
const register long x23 asm ("x23");
const register long x24 asm ("x24");
const register long x25 asm ("x25");
const register long x26 asm ("x26");
const register long x27 asm ("x27");
const register long x28 asm ("x28");
const register long x29 asm ("x29");
arr[0] = x19;
arr[1] = x20;
arr[2] = x21;
arr[3] = x22;
arr[4] = x23;
arr[5] = x24;
arr[6] = x25;
arr[7] = x26;
arr[8] = x27;
arr[9] = x28;
arr[10] = x29;
}
#else
#error "Architecture not supported for gc_helper_get_regs. Set MICROPY_GCREGS_SETJMP to use the fallback implementation."
#endif
#else // !MICROPY_GCREGS_SETJMP
// Even if we have specific support for an architecture, it is
// possible to force use of setjmp-based implementation.
STATIC void gc_helper_get_regs(gc_helper_regs_t arr) {
setjmp(arr);
}
#endif // MICROPY_GCREGS_SETJMP
// Explicitly mark this as noinline to make sure the regs variable
// is effectively at the top of the stack: otherwise, in builds where
// LTO is enabled and a lot of inlining takes place we risk a stack
// layout where regs is lower on the stack than pointers which have
// just been allocated but not yet marked, and get incorrectly sweeped.
MP_NOINLINE void gc_helper_collect_regs_and_stack(void) {
gc_helper_regs_t regs;
gc_helper_get_regs(regs);
// GC stack (and regs because we captured them)
void **regs_ptr = (void **)(void *)&regs;
gc_collect_root(regs_ptr, ((uintptr_t)MP_STATE_THREAD(stack_top) - (uintptr_t)&regs) / sizeof(uintptr_t));
}
#endif // MICROPY_ENABLE_GC