1 /* Copyright (C) 1999-2021 Free Software Foundation, Inc. 2 This file is part of the GNU C Library. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Lesser General Public 6 License as published by the Free Software Foundation; either 7 version 2.1 of the License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with the GNU C Library. If not, see 16 <https://www.gnu.org/licenses/>. */ 17 18 /* This file contains a bit of information about the stack allocation 19 of the processor. */ 20 21 #ifndef _STACKINFO_H 22 #define _STACKINFO_H 1 23 24 #include <elf.h> 25 26 /* On m68k the stack grows down. */ 27 #define _STACK_GROWS_DOWN 1 28 29 /* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK 30 is present, but it is presumed absent. */ 31 #define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X) 32 33 /* Access to the stack pointer. */ 34 #define stackinfo_get_sp() \ 35 ({ void *p__; asm volatile ("move.l %%sp, %0" : "=r" (p__)); p__; }) 36 #define stackinfo_sub_sp(ptr) \ 37 ({ ptrdiff_t d__; \ 38 asm volatile ("sub.l %%sp, %0" : "=r" (d__) : "0" (ptr)); \ 39 d__; }) 40 41 #endif /* stackinfo.h */ 42