| /* Darwin/powerpc host-specific hook definitions. |
| Copyright (C) 2003-2020 Free Software Foundation, Inc. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it |
| under the terms of the GNU General Public License as published |
| by the Free Software Foundation; either version 3, or (at your |
| option) any later version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public |
| License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #define IN_TARGET_CODE 1 |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "diagnostic.h" |
| #include <sys/ucontext.h> |
| #include "hosthooks.h" |
| #include "hosthooks-def.h" |
| #include "config/host-darwin.h" |
| |
| static void segv_crash_handler (int); |
| static void segv_handler (int, siginfo_t *, void *); |
| static void darwin_rs6000_extra_signals (void); |
| |
| #ifndef HAVE_DECL_SIGALTSTACK |
| /* This doesn't have a prototype in signal.h in 10.2.x and earlier, |
| fixed in later releases. */ |
| extern int sigaltstack(const struct sigaltstack *, struct sigaltstack *); |
| #endif |
| |
| /* The fields of the mcontext_t type have acquired underscores in later |
| OS versions. */ |
| #ifdef HAS_MCONTEXT_T_UNDERSCORES |
| #define MC_FLD(x) __ ## x |
| #else |
| #define MC_FLD(x) x |
| #endif |
| |
| #undef HOST_HOOKS_EXTRA_SIGNALS |
| #define HOST_HOOKS_EXTRA_SIGNALS darwin_rs6000_extra_signals |
| |
| /* On Darwin/powerpc, hitting the stack limit turns into a SIGSEGV. |
| This code detects the difference between hitting the stack limit and |
| a true wild pointer dereference by looking at the instruction that |
| faulted; only a few kinds of instruction are used to access below |
| the previous bottom of the stack. */ |
| |
| static void |
| segv_crash_handler (int sig ATTRIBUTE_UNUSED) |
| { |
| internal_error ("Segmentation Fault (code)"); |
| } |
| |
| static void |
| segv_handler (int sig ATTRIBUTE_UNUSED, |
| siginfo_t *sip ATTRIBUTE_UNUSED, |
| void *scp) |
| { |
| ucontext_t *uc = (ucontext_t *)scp; |
| sigset_t sigset; |
| unsigned faulting_insn; |
| |
| /* The fault might have happened when trying to run some instruction, in |
| which case the next line will segfault _again_. Handle this case. */ |
| signal (SIGSEGV, segv_crash_handler); |
| sigemptyset (&sigset); |
| sigaddset (&sigset, SIGSEGV); |
| sigprocmask (SIG_UNBLOCK, &sigset, NULL); |
| |
| faulting_insn = *(unsigned *)uc->uc_mcontext->MC_FLD(ss).MC_FLD(srr0); |
| |
| /* Note that this only has to work for GCC, so we don't have to deal |
| with all the possible cases (GCC has no AltiVec code, for |
| instance). It's complicated because Darwin allows stores to |
| below the stack pointer, and the prologue code takes advantage of |
| this. */ |
| |
| if ((faulting_insn & 0xFFFF8000) == 0x94218000 /* stwu %r1, -xxx(%r1) */ |
| || (faulting_insn & 0xFC1F03FF) == 0x7C01016E /* stwux xxx, %r1, xxx */ |
| || (faulting_insn & 0xFC1F8000) == 0x90018000 /* stw xxx, -yyy(%r1) */ |
| || (faulting_insn & 0xFC1F8000) == 0xD8018000 /* stfd xxx, -yyy(%r1) */ |
| || (faulting_insn & 0xFC1F8000) == 0xBC018000 /* stmw xxx, -yyy(%r1) */) |
| { |
| char *shell_name; |
| |
| fnotice (stderr, "Out of stack space.\n"); |
| shell_name = getenv ("SHELL"); |
| if (shell_name != NULL) |
| shell_name = strrchr (shell_name, '/'); |
| if (shell_name != NULL) |
| { |
| static const char * shell_commands[][2] = { |
| { "sh", "ulimit -S -s unlimited" }, |
| { "bash", "ulimit -S -s unlimited" }, |
| { "tcsh", "limit stacksize unlimited" }, |
| { "csh", "limit stacksize unlimited" }, |
| /* zsh doesn't have "unlimited", this will work under the |
| default configuration. */ |
| { "zsh", "limit stacksize 32m" } |
| }; |
| size_t i; |
| |
| for (i = 0; i < ARRAY_SIZE (shell_commands); i++) |
| if (strcmp (shell_commands[i][0], shell_name + 1) == 0) |
| { |
| fnotice (stderr, |
| "Try running '%s' in the shell to raise its limit.\n", |
| shell_commands[i][1]); |
| } |
| } |
| |
| if (global_dc->abort_on_error) |
| fancy_abort (__FILE__, __LINE__, __FUNCTION__); |
| |
| exit (FATAL_EXIT_CODE); |
| } |
| |
| fprintf (stderr, "[address=%08lx pc=%08x]\n", |
| uc->uc_mcontext->MC_FLD(es).MC_FLD(dar), |
| uc->uc_mcontext->MC_FLD(ss).MC_FLD(srr0)); |
| internal_error ("Segmentation Fault"); |
| exit (FATAL_EXIT_CODE); |
| } |
| |
| static void |
| darwin_rs6000_extra_signals (void) |
| { |
| struct sigaction sact; |
| stack_t sigstk; |
| |
| sigstk.ss_sp = (char*)xmalloc (SIGSTKSZ); |
| sigstk.ss_size = SIGSTKSZ; |
| sigstk.ss_flags = 0; |
| if (sigaltstack (&sigstk, NULL) < 0) |
| fatal_error (input_location, "While setting up signal stack: %m"); |
| |
| sigemptyset(&sact.sa_mask); |
| sact.sa_flags = SA_ONSTACK | SA_SIGINFO; |
| sact.sa_sigaction = segv_handler; |
| if (sigaction (SIGSEGV, &sact, 0) < 0) |
| fatal_error (input_location, "While setting up signal handler: %m"); |
| } |
| |
| |
| const struct host_hooks host_hooks = HOST_HOOKS_INITIALIZER; |