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/* |
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* sigsegv.cpp - SIGSEGV signals support |
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* |
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* Derived from Bruno Haible's work on his SIGSEGV library for clisp |
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* <http://clisp.sourceforge.net/> |
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* |
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* MacOS X support derived from the post by Timothy J. Wood to the |
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* omnigroup macosx-dev list: |
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* Mach Exception Handlers 101 (Was Re: ptrace, gdb) |
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* tjw@omnigroup.com Sun, 4 Jun 2000 |
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* www.omnigroup.com/mailman/archive/macosx-dev/2000-June/002030.html |
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* |
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* Basilisk II (C) 1997-2002 Christian Bauer |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2 of the License, or |
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* (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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*/ |
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|
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#ifdef HAVE_UNISTD_H |
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#include <unistd.h> |
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#endif |
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|
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#ifdef HAVE_CONFIG_H |
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#include "config.h" |
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#endif |
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|
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#include <list> |
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#include <stdio.h> |
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#include <signal.h> |
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#include "sigsegv.h" |
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|
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#ifndef NO_STD_NAMESPACE |
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using std::list; |
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#endif |
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|
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// Return value type of a signal handler (standard type if not defined) |
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#ifndef RETSIGTYPE |
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#define RETSIGTYPE void |
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#endif |
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|
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// Type of the system signal handler |
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typedef RETSIGTYPE (*signal_handler)(int); |
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|
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// User's SIGSEGV handler |
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static sigsegv_fault_handler_t sigsegv_fault_handler = 0; |
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|
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// Function called to dump state if we can't handle the fault |
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static sigsegv_state_dumper_t sigsegv_state_dumper = 0; |
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|
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// Actual SIGSEGV handler installer |
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static bool sigsegv_do_install_handler(int sig); |
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|
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|
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/* |
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* Instruction decoding aids |
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*/ |
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|
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// Transfer size |
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enum transfer_size_t { |
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SIZE_UNKNOWN, |
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SIZE_BYTE, |
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SIZE_WORD, // 2 bytes |
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SIZE_LONG, // 4 bytes |
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SIZE_QUAD, // 8 bytes |
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}; |
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|
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// Transfer type |
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typedef sigsegv_transfer_type_t transfer_type_t; |
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|
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#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__)) |
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// Addressing mode |
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enum addressing_mode_t { |
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MODE_UNKNOWN, |
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MODE_NORM, |
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MODE_U, |
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MODE_X, |
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MODE_UX |
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}; |
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|
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// Decoded instruction |
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struct instruction_t { |
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transfer_type_t transfer_type; |
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transfer_size_t transfer_size; |
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addressing_mode_t addr_mode; |
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unsigned int addr; |
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char ra, rd; |
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}; |
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|
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static void powerpc_decode_instruction(instruction_t *instruction, unsigned int nip, unsigned int * gpr) |
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{ |
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// Get opcode and divide into fields |
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unsigned int opcode = *((unsigned int *)nip); |
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unsigned int primop = opcode >> 26; |
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unsigned int exop = (opcode >> 1) & 0x3ff; |
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unsigned int ra = (opcode >> 16) & 0x1f; |
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unsigned int rb = (opcode >> 11) & 0x1f; |
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unsigned int rd = (opcode >> 21) & 0x1f; |
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signed int imm = (signed short)(opcode & 0xffff); |
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|
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// Analyze opcode |
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transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN; |
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transfer_size_t transfer_size = SIZE_UNKNOWN; |
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addressing_mode_t addr_mode = MODE_UNKNOWN; |
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switch (primop) { |
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case 31: |
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switch (exop) { |
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case 23: // lwzx |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_X; break; |
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case 55: // lwzux |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break; |
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case 87: // lbzx |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break; |
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case 119: // lbzux |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break; |
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case 151: // stwx |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_X; break; |
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case 183: // stwux |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_UX; break; |
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case 215: // stbx |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_X; break; |
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case 247: // stbux |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_UX; break; |
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case 279: // lhzx |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break; |
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case 311: // lhzux |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break; |
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case 343: // lhax |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_X; break; |
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case 375: // lhaux |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break; |
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case 407: // sthx |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_X; break; |
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case 439: // sthux |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_UX; break; |
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} |
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break; |
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|
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case 32: // lwz |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break; |
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case 33: // lwzu |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_LONG; addr_mode = MODE_U; break; |
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case 34: // lbz |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break; |
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case 35: // lbzu |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break; |
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case 36: // stw |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_NORM; break; |
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case 37: // stwu |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_LONG; addr_mode = MODE_U; break; |
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case 38: // stb |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_NORM; break; |
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case 39: // stbu |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_BYTE; addr_mode = MODE_U; break; |
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case 40: // lhz |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break; |
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case 41: // lhzu |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break; |
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case 42: // lha |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break; |
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case 43: // lhau |
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transfer_type = SIGSEGV_TRANSFER_LOAD; transfer_size = SIZE_WORD; addr_mode = MODE_U; break; |
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case 44: // sth |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_NORM; break; |
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case 45: // sthu |
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transfer_type = SIGSEGV_TRANSFER_STORE; transfer_size = SIZE_WORD; addr_mode = MODE_U; break; |
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} |
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|
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// Calculate effective address |
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unsigned int addr = 0; |
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switch (addr_mode) { |
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case MODE_X: |
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case MODE_UX: |
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if (ra == 0) |
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addr = gpr[rb]; |
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else |
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addr = gpr[ra] + gpr[rb]; |
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break; |
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case MODE_NORM: |
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case MODE_U: |
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if (ra == 0) |
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addr = (signed int)(signed short)imm; |
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else |
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addr = gpr[ra] + (signed int)(signed short)imm; |
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break; |
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default: |
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break; |
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} |
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|
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// Commit decoded instruction |
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instruction->addr = addr; |
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instruction->addr_mode = addr_mode; |
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instruction->transfer_type = transfer_type; |
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instruction->transfer_size = transfer_size; |
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instruction->ra = ra; |
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instruction->rd = rd; |
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} |
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#endif |
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|
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|
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/* |
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* OS-dependant SIGSEGV signals support section |
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*/ |
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|
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#if HAVE_SIGINFO_T |
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// Generic extended signal handler |
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#if defined(__NetBSD__) || defined(__FreeBSD__) |
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#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS) |
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#else |
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#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
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#endif |
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#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, siginfo_t *sip, void *scp |
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#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 siginfo_t *sip, void *scp |
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#define SIGSEGV_FAULT_HANDLER_ARGS sip, scp |
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#define SIGSEGV_FAULT_ADDRESS sip->si_addr |
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#if (defined(sgi) || defined(__sgi)) |
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#include <ucontext.h> |
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#define SIGSEGV_CONTEXT_REGS (((ucontext_t *)scp)->uc_mcontext.gregs) |
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#define SIGSEGV_FAULT_INSTRUCTION (unsigned long)SIGSEGV_CONTEXT_REGS[CTX_EPC] |
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#if (defined(mips) || defined(__mips)) |
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#define SIGSEGV_REGISTER_FILE SIGSEGV_CONTEXT_REGS |
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#define SIGSEGV_SKIP_INSTRUCTION mips_skip_instruction |
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#endif |
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#endif |
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#if defined(__sun__) |
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#if (defined(sparc) || defined(__sparc__)) |
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#include <sys/stack.h> |
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#include <sys/regset.h> |
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#include <sys/ucontext.h> |
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#define SIGSEGV_CONTEXT_REGS (((ucontext_t *)scp)->uc_mcontext.gregs) |
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#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_CONTEXT_REGS[REG_PC] |
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#define SIGSEGV_SPARC_GWINDOWS (((ucontext_t *)scp)->uc_mcontext.gwins) |
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#define SIGSEGV_SPARC_RWINDOW (struct rwindow *)((char *)SIGSEGV_CONTEXT_REGS[REG_SP] + STACK_BIAS) |
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#define SIGSEGV_REGISTER_FILE ((unsigned long *)SIGSEGV_CONTEXT_REGS), SIGSEGV_SPARC_GWINDOWS, SIGSEGV_SPARC_RWINDOW |
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#define SIGSEGV_SKIP_INSTRUCTION sparc_skip_instruction |
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#endif |
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#endif |
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#if defined(__FreeBSD__) |
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#if (defined(i386) || defined(__i386__)) |
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#define SIGSEGV_FAULT_INSTRUCTION (((struct sigcontext *)scp)->sc_eip) |
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#define SIGSEGV_REGISTER_FILE ((unsigned long *)&(((struct sigcontext *)scp)->sc_edi)) /* EDI is the first GPR (even below EIP) in sigcontext */ |
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#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction |
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#endif |
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#endif |
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#if defined(__linux__) |
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#if (defined(i386) || defined(__i386__)) |
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#include <sys/ucontext.h> |
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#define SIGSEGV_CONTEXT_REGS (((ucontext_t *)scp)->uc_mcontext.gregs) |
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#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_CONTEXT_REGS[14] /* should use REG_EIP instead */ |
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#define SIGSEGV_REGISTER_FILE (unsigned long *)SIGSEGV_CONTEXT_REGS |
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#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction |
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#endif |
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#if (defined(x86_64) || defined(__x86_64__)) |
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#include <sys/ucontext.h> |
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#define SIGSEGV_CONTEXT_REGS (((ucontext_t *)scp)->uc_mcontext.gregs) |
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#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_CONTEXT_REGS[16] /* should use REG_RIP instead */ |
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#define SIGSEGV_REGISTER_FILE (unsigned long *)SIGSEGV_CONTEXT_REGS |
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#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction |
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#endif |
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#if (defined(ia64) || defined(__ia64__)) |
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#define SIGSEGV_FAULT_INSTRUCTION (((struct sigcontext *)scp)->sc_ip & ~0x3ULL) /* slot number is in bits 0 and 1 */ |
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#endif |
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#if (defined(powerpc) || defined(__powerpc__)) |
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#include <sys/ucontext.h> |
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#define SIGSEGV_CONTEXT_REGS (((ucontext_t *)scp)->uc_mcontext.regs) |
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#define SIGSEGV_FAULT_INSTRUCTION (SIGSEGV_CONTEXT_REGS->nip) |
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#define SIGSEGV_REGISTER_FILE (unsigned int *)&SIGSEGV_CONTEXT_REGS->nip, (unsigned int *)(SIGSEGV_CONTEXT_REGS->gpr) |
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#define SIGSEGV_SKIP_INSTRUCTION powerpc_skip_instruction |
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#endif |
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#if (defined(hppa) || defined(__hppa__)) |
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#undef SIGSEGV_FAULT_ADDRESS |
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#define SIGSEGV_FAULT_ADDRESS sip->si_ptr |
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#endif |
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#endif |
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#endif |
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|
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#if HAVE_SIGCONTEXT_SUBTERFUGE |
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// Linux kernels prior to 2.4 ? |
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#if defined(__linux__) |
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#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
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#if (defined(i386) || defined(__i386__)) |
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#include <asm/sigcontext.h> |
293 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext scs |
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#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 struct sigcontext *scp |
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#define SIGSEGV_FAULT_HANDLER_ARGS &scs |
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#define SIGSEGV_FAULT_ADDRESS scp->cr2 |
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#define SIGSEGV_FAULT_INSTRUCTION scp->eip |
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#define SIGSEGV_REGISTER_FILE (unsigned long *)scp |
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#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction |
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#endif |
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#if (defined(sparc) || defined(__sparc__)) |
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#include <asm/sigcontext.h> |
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#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp, char *addr |
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#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp, addr |
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#define SIGSEGV_FAULT_ADDRESS addr |
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#endif |
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#if (defined(powerpc) || defined(__powerpc__)) |
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#include <asm/sigcontext.h> |
309 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, struct sigcontext *scp |
310 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, scp |
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#define SIGSEGV_FAULT_ADDRESS scp->regs->dar |
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#define SIGSEGV_FAULT_INSTRUCTION scp->regs->nip |
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#define SIGSEGV_REGISTER_FILE (unsigned int *)&scp->regs->nip, (unsigned int *)(scp->regs->gpr) |
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#define SIGSEGV_SKIP_INSTRUCTION powerpc_skip_instruction |
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#endif |
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#if (defined(alpha) || defined(__alpha__)) |
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#include <asm/sigcontext.h> |
318 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
319 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
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#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp) |
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#define SIGSEGV_FAULT_INSTRUCTION scp->sc_pc |
322 |
#endif |
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#endif |
324 |
|
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// Irix 5 or 6 on MIPS |
326 |
#if (defined(sgi) || defined(__sgi)) && (defined(SYSTYPE_SVR4) || defined(_SYSTYPE_SVR4)) |
327 |
#include <ucontext.h> |
328 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
329 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
330 |
#define SIGSEGV_FAULT_ADDRESS (unsigned long)scp->sc_badvaddr |
331 |
#define SIGSEGV_FAULT_INSTRUCTION (unsigned long)scp->sc_pc |
332 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
333 |
#endif |
334 |
|
335 |
// HP-UX |
336 |
#if (defined(hpux) || defined(__hpux__)) |
337 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
338 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
339 |
#define SIGSEGV_FAULT_ADDRESS scp->sc_sl.sl_ss.ss_narrow.ss_cr21 |
340 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) FAULT_HANDLER(SIGBUS) |
341 |
#endif |
342 |
|
343 |
// OSF/1 on Alpha |
344 |
#if defined(__osf__) |
345 |
#include <ucontext.h> |
346 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
347 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
348 |
#define SIGSEGV_FAULT_ADDRESS scp->sc_traparg_a0 |
349 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
350 |
#endif |
351 |
|
352 |
// AIX |
353 |
#if defined(_AIX) |
354 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
355 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
356 |
#define SIGSEGV_FAULT_ADDRESS scp->sc_jmpbuf.jmp_context.o_vaddr |
357 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
358 |
#endif |
359 |
|
360 |
// NetBSD |
361 |
#if defined(__NetBSD__) |
362 |
#if (defined(m68k) || defined(__m68k__)) |
363 |
#include <m68k/frame.h> |
364 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
365 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
366 |
#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp) |
367 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
368 |
|
369 |
// Use decoding scheme from BasiliskII/m68k native |
370 |
static sigsegv_address_t get_fault_address(struct sigcontext *scp) |
371 |
{ |
372 |
struct sigstate { |
373 |
int ss_flags; |
374 |
struct frame ss_frame; |
375 |
}; |
376 |
struct sigstate *state = (struct sigstate *)scp->sc_ap; |
377 |
char *fault_addr; |
378 |
switch (state->ss_frame.f_format) { |
379 |
case 7: /* 68040 access error */ |
380 |
/* "code" is sometimes unreliable (i.e. contains NULL or a bogus address), reason unknown */ |
381 |
fault_addr = state->ss_frame.f_fmt7.f_fa; |
382 |
break; |
383 |
default: |
384 |
fault_addr = (char *)code; |
385 |
break; |
386 |
} |
387 |
return (sigsegv_address_t)fault_addr; |
388 |
} |
389 |
#endif |
390 |
#if (defined(alpha) || defined(__alpha__)) |
391 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
392 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
393 |
#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp) |
394 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS) |
395 |
#endif |
396 |
#if (defined(i386) || defined(__i386__)) |
397 |
#error "FIXME: need to decode instruction and compute EA" |
398 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
399 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
400 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
401 |
#endif |
402 |
#endif |
403 |
#if defined(__FreeBSD__) |
404 |
#if (defined(i386) || defined(__i386__)) |
405 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS) |
406 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp, char *addr |
407 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp, addr |
408 |
#define SIGSEGV_FAULT_ADDRESS addr |
409 |
#define SIGSEGV_FAULT_INSTRUCTION scp->sc_eip |
410 |
#define SIGSEGV_REGISTER_FILE ((unsigned long *)&scp->sc_edi) |
411 |
#define SIGSEGV_SKIP_INSTRUCTION ix86_skip_instruction |
412 |
#endif |
413 |
#if (defined(alpha) || defined(__alpha__)) |
414 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGSEGV) |
415 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, char *addr, struct sigcontext *scp |
416 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, addr, scp |
417 |
#define SIGSEGV_FAULT_ADDRESS addr |
418 |
#define SIGSEGV_FAULT_INSTRUCTION scp->sc_pc |
419 |
#endif |
420 |
#endif |
421 |
|
422 |
// Extract fault address out of a sigcontext |
423 |
#if (defined(alpha) || defined(__alpha__)) |
424 |
// From Boehm's GC 6.0alpha8 |
425 |
static sigsegv_address_t get_fault_address(struct sigcontext *scp) |
426 |
{ |
427 |
unsigned int instruction = *((unsigned int *)(scp->sc_pc)); |
428 |
unsigned long fault_address = scp->sc_regs[(instruction >> 16) & 0x1f]; |
429 |
fault_address += (signed long)(signed short)(instruction & 0xffff); |
430 |
return (sigsegv_address_t)fault_address; |
431 |
} |
432 |
#endif |
433 |
|
434 |
|
435 |
// MacOS X, not sure which version this works in. Under 10.1 |
436 |
// vm_protect does not appear to work from a signal handler. Under |
437 |
// 10.2 signal handlers get siginfo type arguments but the si_addr |
438 |
// field is the address of the faulting instruction and not the |
439 |
// address that caused the SIGBUS. Maybe this works in 10.0? In any |
440 |
// case with Mach exception handlers there is a way to do what this |
441 |
// was meant to do. |
442 |
#ifndef HAVE_MACH_EXCEPTIONS |
443 |
#if defined(__APPLE__) && defined(__MACH__) |
444 |
#if (defined(ppc) || defined(__ppc__)) |
445 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST int sig, int code, struct sigcontext *scp |
446 |
#define SIGSEGV_FAULT_HANDLER_ARGS sig, code, scp |
447 |
#define SIGSEGV_FAULT_ADDRESS get_fault_address(scp) |
448 |
#define SIGSEGV_FAULT_INSTRUCTION scp->sc_ir |
449 |
#define SIGSEGV_ALL_SIGNALS FAULT_HANDLER(SIGBUS) |
450 |
#define SIGSEGV_REGISTER_FILE (unsigned int *)&scp->sc_ir, &((unsigned int *) scp->sc_regs)[2] |
451 |
#define SIGSEGV_SKIP_INSTRUCTION powerpc_skip_instruction |
452 |
|
453 |
// Use decoding scheme from SheepShaver |
454 |
static sigsegv_address_t get_fault_address(struct sigcontext *scp) |
455 |
{ |
456 |
unsigned int nip = (unsigned int) scp->sc_ir; |
457 |
unsigned int * gpr = &((unsigned int *) scp->sc_regs)[2]; |
458 |
instruction_t instr; |
459 |
|
460 |
powerpc_decode_instruction(&instr, nip, gpr); |
461 |
return (sigsegv_address_t)instr.addr; |
462 |
} |
463 |
#endif |
464 |
#endif |
465 |
#endif |
466 |
#endif |
467 |
|
468 |
#if HAVE_MACH_EXCEPTIONS |
469 |
|
470 |
// This can easily be extended to other Mach systems, but really who |
471 |
// uses HURD (oops GNU/HURD), Darwin/x86, NextStep, Rhapsody, or CMU |
472 |
// Mach 2.5/3.0? |
473 |
#if defined(__APPLE__) && defined(__MACH__) |
474 |
|
475 |
#include <sys/types.h> |
476 |
#include <stdlib.h> |
477 |
#include <stdio.h> |
478 |
#include <pthread.h> |
479 |
|
480 |
/* |
481 |
* If you are familiar with MIG then you will understand the frustration |
482 |
* that was necessary to get these embedded into C++ code by hand. |
483 |
*/ |
484 |
extern "C" { |
485 |
#include <mach/mach.h> |
486 |
#include <mach/mach_error.h> |
487 |
|
488 |
extern boolean_t exc_server(mach_msg_header_t *, mach_msg_header_t *); |
489 |
extern kern_return_t catch_exception_raise(mach_port_t, mach_port_t, |
490 |
mach_port_t, exception_type_t, exception_data_t, mach_msg_type_number_t); |
491 |
extern kern_return_t exception_raise(mach_port_t, mach_port_t, mach_port_t, |
492 |
exception_type_t, exception_data_t, mach_msg_type_number_t); |
493 |
extern kern_return_t exception_raise_state(mach_port_t, exception_type_t, |
494 |
exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *, |
495 |
thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *); |
496 |
extern kern_return_t exception_raise_state_identity(mach_port_t, mach_port_t, mach_port_t, |
497 |
exception_type_t, exception_data_t, mach_msg_type_number_t, thread_state_flavor_t *, |
498 |
thread_state_t, mach_msg_type_number_t, thread_state_t, mach_msg_type_number_t *); |
499 |
} |
500 |
|
501 |
// Could make this dynamic by looking for a result of MIG_ARRAY_TOO_LARGE |
502 |
#define HANDLER_COUNT 64 |
503 |
|
504 |
// structure to tuck away existing exception handlers |
505 |
typedef struct _ExceptionPorts { |
506 |
mach_msg_type_number_t maskCount; |
507 |
exception_mask_t masks[HANDLER_COUNT]; |
508 |
exception_handler_t handlers[HANDLER_COUNT]; |
509 |
exception_behavior_t behaviors[HANDLER_COUNT]; |
510 |
thread_state_flavor_t flavors[HANDLER_COUNT]; |
511 |
} ExceptionPorts; |
512 |
|
513 |
// exception handler thread |
514 |
static pthread_t exc_thread; |
515 |
|
516 |
// place where old exception handler info is stored |
517 |
static ExceptionPorts ports; |
518 |
|
519 |
// our exception port |
520 |
static mach_port_t _exceptionPort = MACH_PORT_NULL; |
521 |
|
522 |
#define MACH_CHECK_ERROR(name,ret) \ |
523 |
if (ret != KERN_SUCCESS) { \ |
524 |
mach_error(#name, ret); \ |
525 |
exit (1); \ |
526 |
} |
527 |
|
528 |
#define SIGSEGV_FAULT_ADDRESS code[1] |
529 |
#define SIGSEGV_FAULT_INSTRUCTION get_fault_instruction(thread, state) |
530 |
#define SIGSEGV_FAULT_HANDLER_INVOKE(ADDR, IP) ((code[0] == KERN_PROTECTION_FAILURE) ? sigsegv_fault_handler(ADDR, IP) : SIGSEGV_RETURN_FAILURE) |
531 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST mach_port_t thread, exception_data_t code, ppc_thread_state_t *state |
532 |
#define SIGSEGV_FAULT_HANDLER_ARGS thread, code, &state |
533 |
#define SIGSEGV_SKIP_INSTRUCTION powerpc_skip_instruction |
534 |
#define SIGSEGV_REGISTER_FILE &state->srr0, &state->r0 |
535 |
|
536 |
// Given a suspended thread, stuff the current instruction and |
537 |
// registers into state. |
538 |
// |
539 |
// It would have been nice to have this be ppc/x86 independant which |
540 |
// could have been done easily with a thread_state_t instead of |
541 |
// ppc_thread_state_t, but because of the way this is called it is |
542 |
// easier to do it this way. |
543 |
#if (defined(ppc) || defined(__ppc__)) |
544 |
static inline sigsegv_address_t get_fault_instruction(mach_port_t thread, ppc_thread_state_t *state) |
545 |
{ |
546 |
kern_return_t krc; |
547 |
mach_msg_type_number_t count; |
548 |
|
549 |
count = MACHINE_THREAD_STATE_COUNT; |
550 |
krc = thread_get_state(thread, MACHINE_THREAD_STATE, (thread_state_t)state, &count); |
551 |
MACH_CHECK_ERROR (thread_get_state, krc); |
552 |
|
553 |
return (sigsegv_address_t)state->srr0; |
554 |
} |
555 |
#endif |
556 |
|
557 |
// Since there can only be one exception thread running at any time |
558 |
// this is not a problem. |
559 |
#define MSG_SIZE 512 |
560 |
static char msgbuf[MSG_SIZE]; |
561 |
static char replybuf[MSG_SIZE]; |
562 |
|
563 |
/* |
564 |
* This is the entry point for the exception handler thread. The job |
565 |
* of this thread is to wait for exception messages on the exception |
566 |
* port that was setup beforehand and to pass them on to exc_server. |
567 |
* exc_server is a MIG generated function that is a part of Mach. |
568 |
* Its job is to decide what to do with the exception message. In our |
569 |
* case exc_server calls catch_exception_raise on our behalf. After |
570 |
* exc_server returns, it is our responsibility to send the reply. |
571 |
*/ |
572 |
static void * |
573 |
handleExceptions(void *priv) |
574 |
{ |
575 |
mach_msg_header_t *msg, *reply; |
576 |
kern_return_t krc; |
577 |
|
578 |
msg = (mach_msg_header_t *)msgbuf; |
579 |
reply = (mach_msg_header_t *)replybuf; |
580 |
|
581 |
for (;;) { |
582 |
krc = mach_msg(msg, MACH_RCV_MSG, MSG_SIZE, MSG_SIZE, |
583 |
_exceptionPort, 0, MACH_PORT_NULL); |
584 |
MACH_CHECK_ERROR(mach_msg, krc); |
585 |
|
586 |
if (!exc_server(msg, reply)) { |
587 |
fprintf(stderr, "exc_server hated the message\n"); |
588 |
exit(1); |
589 |
} |
590 |
|
591 |
krc = mach_msg(reply, MACH_SEND_MSG, reply->msgh_size, 0, |
592 |
msg->msgh_local_port, 0, MACH_PORT_NULL); |
593 |
if (krc != KERN_SUCCESS) { |
594 |
fprintf(stderr, "Error sending message to original reply port, krc = %d, %s", |
595 |
krc, mach_error_string(krc)); |
596 |
exit(1); |
597 |
} |
598 |
} |
599 |
} |
600 |
#endif |
601 |
#endif |
602 |
|
603 |
|
604 |
/* |
605 |
* Instruction skipping |
606 |
*/ |
607 |
|
608 |
#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION |
609 |
// Decode and skip X86 instruction |
610 |
#if (defined(i386) || defined(__i386__)) || defined(__x86_64__) |
611 |
#if defined(__linux__) |
612 |
enum { |
613 |
#if (defined(i386) || defined(__i386__)) |
614 |
X86_REG_EIP = 14, |
615 |
X86_REG_EAX = 11, |
616 |
X86_REG_ECX = 10, |
617 |
X86_REG_EDX = 9, |
618 |
X86_REG_EBX = 8, |
619 |
X86_REG_ESP = 7, |
620 |
X86_REG_EBP = 6, |
621 |
X86_REG_ESI = 5, |
622 |
X86_REG_EDI = 4 |
623 |
#endif |
624 |
#if defined(__x86_64__) |
625 |
X86_REG_R8 = 0, |
626 |
X86_REG_R9 = 1, |
627 |
X86_REG_R10 = 2, |
628 |
X86_REG_R11 = 3, |
629 |
X86_REG_R12 = 4, |
630 |
X86_REG_R13 = 5, |
631 |
X86_REG_R14 = 6, |
632 |
X86_REG_R15 = 7, |
633 |
X86_REG_EDI = 8, |
634 |
X86_REG_ESI = 9, |
635 |
X86_REG_EBP = 10, |
636 |
X86_REG_EBX = 11, |
637 |
X86_REG_EDX = 12, |
638 |
X86_REG_EAX = 13, |
639 |
X86_REG_ECX = 14, |
640 |
X86_REG_ESP = 15, |
641 |
X86_REG_EIP = 16 |
642 |
#endif |
643 |
}; |
644 |
#endif |
645 |
#if defined(__NetBSD__) || defined(__FreeBSD__) |
646 |
enum { |
647 |
#if (defined(i386) || defined(__i386__)) |
648 |
X86_REG_EIP = 10, |
649 |
X86_REG_EAX = 7, |
650 |
X86_REG_ECX = 6, |
651 |
X86_REG_EDX = 5, |
652 |
X86_REG_EBX = 4, |
653 |
X86_REG_ESP = 13, |
654 |
X86_REG_EBP = 2, |
655 |
X86_REG_ESI = 1, |
656 |
X86_REG_EDI = 0 |
657 |
#endif |
658 |
}; |
659 |
#endif |
660 |
// FIXME: this is partly redundant with the instruction decoding phase |
661 |
// to discover transfer type and register number |
662 |
static inline int ix86_step_over_modrm(unsigned char * p) |
663 |
{ |
664 |
int mod = (p[0] >> 6) & 3; |
665 |
int rm = p[0] & 7; |
666 |
int offset = 0; |
667 |
|
668 |
// ModR/M Byte |
669 |
switch (mod) { |
670 |
case 0: // [reg] |
671 |
if (rm == 5) return 4; // disp32 |
672 |
break; |
673 |
case 1: // disp8[reg] |
674 |
offset = 1; |
675 |
break; |
676 |
case 2: // disp32[reg] |
677 |
offset = 4; |
678 |
break; |
679 |
case 3: // register |
680 |
return 0; |
681 |
} |
682 |
|
683 |
// SIB Byte |
684 |
if (rm == 4) { |
685 |
if (mod == 0 && (p[1] & 7) == 5) |
686 |
offset = 5; // disp32[index] |
687 |
else |
688 |
offset++; |
689 |
} |
690 |
|
691 |
return offset; |
692 |
} |
693 |
|
694 |
static bool ix86_skip_instruction(unsigned long * regs) |
695 |
{ |
696 |
unsigned char * eip = (unsigned char *)regs[X86_REG_EIP]; |
697 |
|
698 |
if (eip == 0) |
699 |
return false; |
700 |
|
701 |
transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN; |
702 |
transfer_size_t transfer_size = SIZE_LONG; |
703 |
|
704 |
int reg = -1; |
705 |
int len = 0; |
706 |
|
707 |
#if DEBUG |
708 |
printf("IP: %p [%02x %02x %02x %02x...]\n", |
709 |
eip, eip[0], eip[1], eip[2], eip[3]); |
710 |
#endif |
711 |
|
712 |
// Operand size prefix |
713 |
if (*eip == 0x66) { |
714 |
eip++; |
715 |
len++; |
716 |
transfer_size = SIZE_WORD; |
717 |
} |
718 |
|
719 |
// REX prefix |
720 |
#if defined(__x86_64__) |
721 |
struct rex_t { |
722 |
unsigned char W; |
723 |
unsigned char R; |
724 |
unsigned char X; |
725 |
unsigned char B; |
726 |
}; |
727 |
rex_t rex = { 0, 0, 0, 0 }; |
728 |
bool has_rex = false; |
729 |
if ((*eip & 0xf0) == 0x40) { |
730 |
has_rex = true; |
731 |
const unsigned char b = *eip; |
732 |
rex.W = b & (1 << 3); |
733 |
rex.R = b & (1 << 2); |
734 |
rex.X = b & (1 << 1); |
735 |
rex.B = b & (1 << 0); |
736 |
#if DEBUG |
737 |
printf("REX: %c,%c,%c,%c\n", |
738 |
rex.W ? 'W' : '_', |
739 |
rex.R ? 'R' : '_', |
740 |
rex.X ? 'X' : '_', |
741 |
rex.B ? 'B' : '_'); |
742 |
#endif |
743 |
eip++; |
744 |
len++; |
745 |
if (rex.W) |
746 |
transfer_size = SIZE_QUAD; |
747 |
} |
748 |
#else |
749 |
const bool has_rex = false; |
750 |
#endif |
751 |
|
752 |
// Decode instruction |
753 |
switch (eip[0]) { |
754 |
case 0x0f: |
755 |
switch (eip[1]) { |
756 |
case 0xb6: // MOVZX r32, r/m8 |
757 |
case 0xb7: // MOVZX r32, r/m16 |
758 |
switch (eip[2] & 0xc0) { |
759 |
case 0x80: |
760 |
reg = (eip[2] >> 3) & 7; |
761 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
762 |
break; |
763 |
case 0x40: |
764 |
reg = (eip[2] >> 3) & 7; |
765 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
766 |
break; |
767 |
case 0x00: |
768 |
reg = (eip[2] >> 3) & 7; |
769 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
770 |
break; |
771 |
} |
772 |
len += 3 + ix86_step_over_modrm(eip + 2); |
773 |
break; |
774 |
} |
775 |
break; |
776 |
case 0x8a: // MOV r8, r/m8 |
777 |
transfer_size = SIZE_BYTE; |
778 |
case 0x8b: // MOV r32, r/m32 (or 16-bit operation) |
779 |
switch (eip[1] & 0xc0) { |
780 |
case 0x80: |
781 |
reg = (eip[1] >> 3) & 7; |
782 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
783 |
break; |
784 |
case 0x40: |
785 |
reg = (eip[1] >> 3) & 7; |
786 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
787 |
break; |
788 |
case 0x00: |
789 |
reg = (eip[1] >> 3) & 7; |
790 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
791 |
break; |
792 |
} |
793 |
len += 2 + ix86_step_over_modrm(eip + 1); |
794 |
break; |
795 |
case 0x88: // MOV r/m8, r8 |
796 |
transfer_size = SIZE_BYTE; |
797 |
case 0x89: // MOV r/m32, r32 (or 16-bit operation) |
798 |
switch (eip[1] & 0xc0) { |
799 |
case 0x80: |
800 |
reg = (eip[1] >> 3) & 7; |
801 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
802 |
break; |
803 |
case 0x40: |
804 |
reg = (eip[1] >> 3) & 7; |
805 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
806 |
break; |
807 |
case 0x00: |
808 |
reg = (eip[1] >> 3) & 7; |
809 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
810 |
break; |
811 |
} |
812 |
len += 2 + ix86_step_over_modrm(eip + 1); |
813 |
break; |
814 |
} |
815 |
|
816 |
if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) { |
817 |
// Unknown machine code, let it crash. Then patch the decoder |
818 |
return false; |
819 |
} |
820 |
|
821 |
#if defined(__x86_64__) |
822 |
if (rex.R) |
823 |
reg += 8; |
824 |
#endif |
825 |
|
826 |
if (transfer_type == SIGSEGV_TRANSFER_LOAD && reg != -1) { |
827 |
static const int x86_reg_map[] = { |
828 |
X86_REG_EAX, X86_REG_ECX, X86_REG_EDX, X86_REG_EBX, |
829 |
X86_REG_ESP, X86_REG_EBP, X86_REG_ESI, X86_REG_EDI, |
830 |
#if defined(__x86_64__) |
831 |
X86_REG_R8, X86_REG_R9, X86_REG_R10, X86_REG_R11, |
832 |
X86_REG_R12, X86_REG_R13, X86_REG_R14, X86_REG_R15, |
833 |
#endif |
834 |
}; |
835 |
|
836 |
if (reg < 0 || reg >= (sizeof(x86_reg_map)/sizeof(x86_reg_map[0]) - 1)) |
837 |
return false; |
838 |
|
839 |
// Set 0 to the relevant register part |
840 |
// NOTE: this is only valid for MOV alike instructions |
841 |
int rloc = x86_reg_map[reg]; |
842 |
switch (transfer_size) { |
843 |
case SIZE_BYTE: |
844 |
if (has_rex || reg < 4) |
845 |
regs[rloc] = (regs[rloc] & ~0x00ffL); |
846 |
else { |
847 |
rloc = x86_reg_map[reg - 4]; |
848 |
regs[rloc] = (regs[rloc] & ~0xff00L); |
849 |
} |
850 |
break; |
851 |
case SIZE_WORD: |
852 |
regs[rloc] = (regs[rloc] & ~0xffffL); |
853 |
break; |
854 |
case SIZE_LONG: |
855 |
case SIZE_QUAD: // zero-extension |
856 |
regs[rloc] = 0; |
857 |
break; |
858 |
} |
859 |
} |
860 |
|
861 |
#if DEBUG |
862 |
printf("%08x: %s %s access", regs[X86_REG_EIP], |
863 |
transfer_size == SIZE_BYTE ? "byte" : |
864 |
transfer_size == SIZE_WORD ? "word" : |
865 |
transfer_size == SIZE_LONG ? "long" : |
866 |
transfer_size == SIZE_QUAD ? "quad" : "unknown", |
867 |
transfer_type == SIGSEGV_TRANSFER_LOAD ? "read" : "write"); |
868 |
|
869 |
if (reg != -1) { |
870 |
static const char * x86_byte_reg_str_map[] = { |
871 |
"al", "cl", "dl", "bl", |
872 |
"spl", "bpl", "sil", "dil", |
873 |
"r8b", "r9b", "r10b", "r11b", |
874 |
"r12b", "r13b", "r14b", "r15b", |
875 |
"ah", "ch", "dh", "bh", |
876 |
}; |
877 |
static const char * x86_word_reg_str_map[] = { |
878 |
"ax", "cx", "dx", "bx", |
879 |
"sp", "bp", "si", "di", |
880 |
"r8w", "r9w", "r10w", "r11w", |
881 |
"r12w", "r13w", "r14w", "r15w", |
882 |
}; |
883 |
static const char *x86_long_reg_str_map[] = { |
884 |
"eax", "ecx", "edx", "ebx", |
885 |
"esp", "ebp", "esi", "edi", |
886 |
"r8d", "r9d", "r10d", "r11d", |
887 |
"r12d", "r13d", "r14d", "r15d", |
888 |
}; |
889 |
static const char *x86_quad_reg_str_map[] = { |
890 |
"rax", "rcx", "rdx", "rbx", |
891 |
"rsp", "rbp", "rsi", "rdi", |
892 |
"r8", "r9", "r10", "r11", |
893 |
"r12", "r13", "r14", "r15", |
894 |
}; |
895 |
const char * reg_str = NULL; |
896 |
switch (transfer_size) { |
897 |
case SIZE_BYTE: |
898 |
reg_str = x86_byte_reg_str_map[(!has_rex && reg >= 4 ? 12 : 0) + reg]; |
899 |
break; |
900 |
case SIZE_WORD: reg_str = x86_word_reg_str_map[reg]; break; |
901 |
case SIZE_LONG: reg_str = x86_long_reg_str_map[reg]; break; |
902 |
case SIZE_QUAD: reg_str = x86_quad_reg_str_map[reg]; break; |
903 |
} |
904 |
if (reg_str) |
905 |
printf(" %s register %%%s", |
906 |
transfer_type == SIGSEGV_TRANSFER_LOAD ? "to" : "from", |
907 |
reg_str); |
908 |
} |
909 |
printf(", %d bytes instruction\n", len); |
910 |
#endif |
911 |
|
912 |
regs[X86_REG_EIP] += len; |
913 |
return true; |
914 |
} |
915 |
#endif |
916 |
|
917 |
// Decode and skip PPC instruction |
918 |
#if (defined(powerpc) || defined(__powerpc__) || defined(__ppc__)) |
919 |
static bool powerpc_skip_instruction(unsigned int * nip_p, unsigned int * regs) |
920 |
{ |
921 |
instruction_t instr; |
922 |
powerpc_decode_instruction(&instr, *nip_p, regs); |
923 |
|
924 |
if (instr.transfer_type == SIGSEGV_TRANSFER_UNKNOWN) { |
925 |
// Unknown machine code, let it crash. Then patch the decoder |
926 |
return false; |
927 |
} |
928 |
|
929 |
#if DEBUG |
930 |
printf("%08x: %s %s access", *nip_p, |
931 |
instr.transfer_size == SIZE_BYTE ? "byte" : instr.transfer_size == SIZE_WORD ? "word" : "long", |
932 |
instr.transfer_type == SIGSEGV_TRANSFER_LOAD ? "read" : "write"); |
933 |
|
934 |
if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX) |
935 |
printf(" r%d (ra = %08x)\n", instr.ra, instr.addr); |
936 |
if (instr.transfer_type == SIGSEGV_TRANSFER_LOAD) |
937 |
printf(" r%d (rd = 0)\n", instr.rd); |
938 |
#endif |
939 |
|
940 |
if (instr.addr_mode == MODE_U || instr.addr_mode == MODE_UX) |
941 |
regs[instr.ra] = instr.addr; |
942 |
if (instr.transfer_type == SIGSEGV_TRANSFER_LOAD) |
943 |
regs[instr.rd] = 0; |
944 |
|
945 |
*nip_p += 4; |
946 |
return true; |
947 |
} |
948 |
#endif |
949 |
|
950 |
// Decode and skip MIPS instruction |
951 |
#if (defined(mips) || defined(__mips)) |
952 |
enum { |
953 |
#if (defined(sgi) || defined(__sgi)) |
954 |
MIPS_REG_EPC = 35, |
955 |
#endif |
956 |
}; |
957 |
static bool mips_skip_instruction(greg_t * regs) |
958 |
{ |
959 |
unsigned int * epc = (unsigned int *)(unsigned long)regs[MIPS_REG_EPC]; |
960 |
|
961 |
if (epc == 0) |
962 |
return false; |
963 |
|
964 |
#if DEBUG |
965 |
printf("IP: %p [%08x]\n", epc, epc[0]); |
966 |
#endif |
967 |
|
968 |
transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN; |
969 |
transfer_size_t transfer_size = SIZE_LONG; |
970 |
int direction = 0; |
971 |
|
972 |
const unsigned int opcode = epc[0]; |
973 |
switch (opcode >> 26) { |
974 |
case 32: // Load Byte |
975 |
case 36: // Load Byte Unsigned |
976 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
977 |
transfer_size = SIZE_BYTE; |
978 |
break; |
979 |
case 33: // Load Halfword |
980 |
case 37: // Load Halfword Unsigned |
981 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
982 |
transfer_size = SIZE_WORD; |
983 |
break; |
984 |
case 35: // Load Word |
985 |
case 39: // Load Word Unsigned |
986 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
987 |
transfer_size = SIZE_LONG; |
988 |
break; |
989 |
case 34: // Load Word Left |
990 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
991 |
transfer_size = SIZE_LONG; |
992 |
direction = -1; |
993 |
break; |
994 |
case 38: // Load Word Right |
995 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
996 |
transfer_size = SIZE_LONG; |
997 |
direction = 1; |
998 |
break; |
999 |
case 55: // Load Doubleword |
1000 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1001 |
transfer_size = SIZE_QUAD; |
1002 |
break; |
1003 |
case 26: // Load Doubleword Left |
1004 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1005 |
transfer_size = SIZE_QUAD; |
1006 |
direction = -1; |
1007 |
break; |
1008 |
case 27: // Load Doubleword Right |
1009 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1010 |
transfer_size = SIZE_QUAD; |
1011 |
direction = 1; |
1012 |
break; |
1013 |
case 40: // Store Byte |
1014 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1015 |
transfer_size = SIZE_BYTE; |
1016 |
break; |
1017 |
case 41: // Store Halfword |
1018 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1019 |
transfer_size = SIZE_WORD; |
1020 |
break; |
1021 |
case 43: // Store Word |
1022 |
case 42: // Store Word Left |
1023 |
case 46: // Store Word Right |
1024 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1025 |
transfer_size = SIZE_LONG; |
1026 |
break; |
1027 |
case 63: // Store Doubleword |
1028 |
case 44: // Store Doubleword Left |
1029 |
case 45: // Store Doubleword Right |
1030 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1031 |
transfer_size = SIZE_QUAD; |
1032 |
break; |
1033 |
/* Misc instructions unlikely to be used within CPU emulators */ |
1034 |
case 48: // Load Linked Word |
1035 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1036 |
transfer_size = SIZE_LONG; |
1037 |
break; |
1038 |
case 52: // Load Linked Doubleword |
1039 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1040 |
transfer_size = SIZE_QUAD; |
1041 |
break; |
1042 |
case 56: // Store Conditional Word |
1043 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1044 |
transfer_size = SIZE_LONG; |
1045 |
break; |
1046 |
case 60: // Store Conditional Doubleword |
1047 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1048 |
transfer_size = SIZE_QUAD; |
1049 |
break; |
1050 |
} |
1051 |
|
1052 |
if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) { |
1053 |
// Unknown machine code, let it crash. Then patch the decoder |
1054 |
return false; |
1055 |
} |
1056 |
|
1057 |
// Zero target register in case of a load operation |
1058 |
const int reg = (opcode >> 16) & 0x1f; |
1059 |
if (transfer_type == SIGSEGV_TRANSFER_LOAD) { |
1060 |
if (direction == 0) |
1061 |
regs[reg] = 0; |
1062 |
else { |
1063 |
// FIXME: untested code |
1064 |
unsigned long ea = regs[(opcode >> 21) & 0x1f]; |
1065 |
ea += (signed long)(signed int)(signed short)(opcode & 0xffff); |
1066 |
const int offset = ea & (transfer_size == SIZE_LONG ? 3 : 7); |
1067 |
unsigned long value; |
1068 |
if (direction > 0) { |
1069 |
const unsigned long rmask = ~((1L << ((offset + 1) * 8)) - 1); |
1070 |
value = regs[reg] & rmask; |
1071 |
} |
1072 |
else { |
1073 |
const unsigned long lmask = (1L << (offset * 8)) - 1; |
1074 |
value = regs[reg] & lmask; |
1075 |
} |
1076 |
// restore most significant bits |
1077 |
if (transfer_size == SIZE_LONG) |
1078 |
value = (signed long)(signed int)value; |
1079 |
regs[reg] = value; |
1080 |
} |
1081 |
} |
1082 |
|
1083 |
#if DEBUG |
1084 |
#if (defined(_ABIN32) || defined(_ABI64)) |
1085 |
static const char * mips_gpr_names[32] = { |
1086 |
"zero", "at", "v0", "v1", "a0", "a1", "a2", "a3", |
1087 |
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", |
1088 |
"s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7", |
1089 |
"t8", "t9", "k0", "k1", "gp", "sp", "s8", "ra" |
1090 |
}; |
1091 |
#else |
1092 |
static const char * mips_gpr_names[32] = { |
1093 |
"zero", "at", "v0", "v1", "a0", "a1", "a2", "a3", |
1094 |
"a4", "a5", "a6", "a7", "t0", "t1", "t2", "t3", |
1095 |
"s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7", |
1096 |
"t8", "t9", "k0", "k1", "gp", "sp", "s8", "ra" |
1097 |
}; |
1098 |
#endif |
1099 |
printf("%s %s register %s\n", |
1100 |
transfer_size == SIZE_BYTE ? "byte" : |
1101 |
transfer_size == SIZE_WORD ? "word" : |
1102 |
transfer_size == SIZE_LONG ? "long" : |
1103 |
transfer_size == SIZE_QUAD ? "quad" : "unknown", |
1104 |
transfer_type == SIGSEGV_TRANSFER_LOAD ? "load to" : "store from", |
1105 |
mips_gpr_names[reg]); |
1106 |
#endif |
1107 |
|
1108 |
regs[MIPS_REG_EPC] += 4; |
1109 |
return true; |
1110 |
} |
1111 |
#endif |
1112 |
|
1113 |
// Decode and skip SPARC instruction |
1114 |
#if (defined(sparc) || defined(__sparc__)) |
1115 |
enum { |
1116 |
#if (defined(__sun__)) |
1117 |
SPARC_REG_G1 = REG_G1, |
1118 |
SPARC_REG_O0 = REG_O0, |
1119 |
SPARC_REG_PC = REG_PC, |
1120 |
#endif |
1121 |
}; |
1122 |
static bool sparc_skip_instruction(unsigned long * regs, gwindows_t * gwins, struct rwindow * rwin) |
1123 |
{ |
1124 |
unsigned int * pc = (unsigned int *)regs[SPARC_REG_PC]; |
1125 |
|
1126 |
if (pc == 0) |
1127 |
return false; |
1128 |
|
1129 |
#if DEBUG |
1130 |
printf("IP: %p [%08x]\n", pc, pc[0]); |
1131 |
#endif |
1132 |
|
1133 |
transfer_type_t transfer_type = SIGSEGV_TRANSFER_UNKNOWN; |
1134 |
transfer_size_t transfer_size = SIZE_LONG; |
1135 |
bool register_pair = false; |
1136 |
|
1137 |
const unsigned int opcode = pc[0]; |
1138 |
if ((opcode >> 30) != 3) |
1139 |
return false; |
1140 |
switch ((opcode >> 19) & 0x3f) { |
1141 |
case 9: // Load Signed Byte |
1142 |
case 1: // Load Unsigned Byte |
1143 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1144 |
transfer_size = SIZE_BYTE; |
1145 |
break; |
1146 |
case 10:// Load Signed Halfword |
1147 |
case 2: // Load Unsigned Word |
1148 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1149 |
transfer_size = SIZE_WORD; |
1150 |
break; |
1151 |
case 8: // Load Word |
1152 |
case 0: // Load Unsigned Word |
1153 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1154 |
transfer_size = SIZE_LONG; |
1155 |
break; |
1156 |
case 11:// Load Extended Word |
1157 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1158 |
transfer_size = SIZE_QUAD; |
1159 |
break; |
1160 |
case 3: // Load Doubleword |
1161 |
transfer_type = SIGSEGV_TRANSFER_LOAD; |
1162 |
transfer_size = SIZE_LONG; |
1163 |
register_pair = true; |
1164 |
break; |
1165 |
case 5: // Store Byte |
1166 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1167 |
transfer_size = SIZE_BYTE; |
1168 |
break; |
1169 |
case 6: // Store Halfword |
1170 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1171 |
transfer_size = SIZE_WORD; |
1172 |
break; |
1173 |
case 4: // Store Word |
1174 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1175 |
transfer_size = SIZE_LONG; |
1176 |
break; |
1177 |
case 14:// Store Extended Word |
1178 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1179 |
transfer_size = SIZE_QUAD; |
1180 |
break; |
1181 |
case 7: // Store Doubleword |
1182 |
transfer_type = SIGSEGV_TRANSFER_STORE; |
1183 |
transfer_size = SIZE_WORD; |
1184 |
register_pair = true; |
1185 |
break; |
1186 |
} |
1187 |
|
1188 |
if (transfer_type == SIGSEGV_TRANSFER_UNKNOWN) { |
1189 |
// Unknown machine code, let it crash. Then patch the decoder |
1190 |
return false; |
1191 |
} |
1192 |
|
1193 |
// Zero target register in case of a load operation |
1194 |
const int reg = (opcode >> 25) & 0x1f; |
1195 |
if (transfer_type == SIGSEGV_TRANSFER_LOAD && reg != 0) { |
1196 |
// FIXME: code to handle local & input registers is not tested |
1197 |
if (reg >= 1 && reg <= 7) { |
1198 |
// global registers |
1199 |
regs[reg - 1 + SPARC_REG_G1] = 0; |
1200 |
} |
1201 |
else if (reg >= 8 && reg <= 15) { |
1202 |
// output registers |
1203 |
regs[reg - 8 + SPARC_REG_O0] = 0; |
1204 |
} |
1205 |
else if (reg >= 16 && reg <= 23) { |
1206 |
// local registers (in register windows) |
1207 |
if (gwins) |
1208 |
gwins->wbuf->rw_local[reg - 16] = 0; |
1209 |
else |
1210 |
rwin->rw_local[reg - 16] = 0; |
1211 |
} |
1212 |
else { |
1213 |
// input registers (in register windows) |
1214 |
if (gwins) |
1215 |
gwins->wbuf->rw_in[reg - 24] = 0; |
1216 |
else |
1217 |
rwin->rw_in[reg - 24] = 0; |
1218 |
} |
1219 |
} |
1220 |
|
1221 |
#if DEBUG |
1222 |
static const char * reg_names[] = { |
1223 |
"g0", "g1", "g2", "g3", "g4", "g5", "g6", "g7", |
1224 |
"o0", "o1", "o2", "o3", "o4", "o5", "sp", "o7", |
1225 |
"l0", "l1", "l2", "l3", "l4", "l5", "l6", "l7", |
1226 |
"i0", "i1", "i2", "i3", "i4", "i5", "fp", "i7" |
1227 |
}; |
1228 |
printf("%s %s register %s\n", |
1229 |
transfer_size == SIZE_BYTE ? "byte" : |
1230 |
transfer_size == SIZE_WORD ? "word" : |
1231 |
transfer_size == SIZE_LONG ? "long" : |
1232 |
transfer_size == SIZE_QUAD ? "quad" : "unknown", |
1233 |
transfer_type == SIGSEGV_TRANSFER_LOAD ? "load to" : "store from", |
1234 |
reg_names[reg]); |
1235 |
#endif |
1236 |
|
1237 |
regs[SPARC_REG_PC] += 4; |
1238 |
return true; |
1239 |
} |
1240 |
#endif |
1241 |
#endif |
1242 |
|
1243 |
// Fallbacks |
1244 |
#ifndef SIGSEGV_FAULT_INSTRUCTION |
1245 |
#define SIGSEGV_FAULT_INSTRUCTION SIGSEGV_INVALID_PC |
1246 |
#endif |
1247 |
#ifndef SIGSEGV_FAULT_HANDLER_ARGLIST_1 |
1248 |
#define SIGSEGV_FAULT_HANDLER_ARGLIST_1 SIGSEGV_FAULT_HANDLER_ARGLIST |
1249 |
#endif |
1250 |
#ifndef SIGSEGV_FAULT_HANDLER_INVOKE |
1251 |
#define SIGSEGV_FAULT_HANDLER_INVOKE(ADDR, IP) sigsegv_fault_handler(ADDR, IP) |
1252 |
#endif |
1253 |
|
1254 |
// SIGSEGV recovery supported ? |
1255 |
#if defined(SIGSEGV_ALL_SIGNALS) && defined(SIGSEGV_FAULT_HANDLER_ARGLIST) && defined(SIGSEGV_FAULT_ADDRESS) |
1256 |
#define HAVE_SIGSEGV_RECOVERY |
1257 |
#endif |
1258 |
|
1259 |
|
1260 |
/* |
1261 |
* SIGSEGV global handler |
1262 |
*/ |
1263 |
|
1264 |
#if defined(HAVE_SIGSEGV_RECOVERY) || defined(HAVE_MACH_EXCEPTIONS) |
1265 |
// This function handles the badaccess to memory. |
1266 |
// It is called from the signal handler or the exception handler. |
1267 |
static bool handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGLIST_1) |
1268 |
{ |
1269 |
sigsegv_address_t fault_address = (sigsegv_address_t)SIGSEGV_FAULT_ADDRESS; |
1270 |
sigsegv_address_t fault_instruction = (sigsegv_address_t)SIGSEGV_FAULT_INSTRUCTION; |
1271 |
|
1272 |
// Call user's handler and reinstall the global handler, if required |
1273 |
switch (SIGSEGV_FAULT_HANDLER_INVOKE(fault_address, fault_instruction)) { |
1274 |
case SIGSEGV_RETURN_SUCCESS: |
1275 |
return true; |
1276 |
|
1277 |
#if HAVE_SIGSEGV_SKIP_INSTRUCTION |
1278 |
case SIGSEGV_RETURN_SKIP_INSTRUCTION: |
1279 |
// Call the instruction skipper with the register file |
1280 |
// available |
1281 |
if (SIGSEGV_SKIP_INSTRUCTION(SIGSEGV_REGISTER_FILE)) { |
1282 |
#ifdef HAVE_MACH_EXCEPTIONS |
1283 |
// Unlike UNIX signals where the thread state |
1284 |
// is modified off of the stack, in Mach we |
1285 |
// need to actually call thread_set_state to |
1286 |
// have the register values updated. |
1287 |
kern_return_t krc; |
1288 |
|
1289 |
krc = thread_set_state(thread, |
1290 |
MACHINE_THREAD_STATE, (thread_state_t)state, |
1291 |
MACHINE_THREAD_STATE_COUNT); |
1292 |
MACH_CHECK_ERROR (thread_get_state, krc); |
1293 |
#endif |
1294 |
return true; |
1295 |
} |
1296 |
break; |
1297 |
#endif |
1298 |
} |
1299 |
|
1300 |
// We can't do anything with the fault_address, dump state? |
1301 |
if (sigsegv_state_dumper != 0) |
1302 |
sigsegv_state_dumper(fault_address, fault_instruction); |
1303 |
|
1304 |
return false; |
1305 |
} |
1306 |
#endif |
1307 |
|
1308 |
|
1309 |
/* |
1310 |
* There are two mechanisms for handling a bad memory access, |
1311 |
* Mach exceptions and UNIX signals. The implementation specific |
1312 |
* code appears below. Its reponsibility is to call handle_badaccess |
1313 |
* which is the routine that handles the fault in an implementation |
1314 |
* agnostic manner. The implementation specific code below is then |
1315 |
* reponsible for checking whether handle_badaccess was able |
1316 |
* to handle the memory access error and perform any implementation |
1317 |
* specific tasks necessary afterwards. |
1318 |
*/ |
1319 |
|
1320 |
#ifdef HAVE_MACH_EXCEPTIONS |
1321 |
/* |
1322 |
* We need to forward all exceptions that we do not handle. |
1323 |
* This is important, there are many exceptions that may be |
1324 |
* handled by other exception handlers. For example debuggers |
1325 |
* use exceptions and the exception hander is in another |
1326 |
* process in such a case. (Timothy J. Wood states in his |
1327 |
* message to the list that he based this code on that from |
1328 |
* gdb for Darwin.) |
1329 |
*/ |
1330 |
static inline kern_return_t |
1331 |
forward_exception(mach_port_t thread_port, |
1332 |
mach_port_t task_port, |
1333 |
exception_type_t exception_type, |
1334 |
exception_data_t exception_data, |
1335 |
mach_msg_type_number_t data_count, |
1336 |
ExceptionPorts *oldExceptionPorts) |
1337 |
{ |
1338 |
kern_return_t kret; |
1339 |
unsigned int portIndex; |
1340 |
mach_port_t port; |
1341 |
exception_behavior_t behavior; |
1342 |
thread_state_flavor_t flavor; |
1343 |
thread_state_t thread_state; |
1344 |
mach_msg_type_number_t thread_state_count; |
1345 |
|
1346 |
for (portIndex = 0; portIndex < oldExceptionPorts->maskCount; portIndex++) { |
1347 |
if (oldExceptionPorts->masks[portIndex] & (1 << exception_type)) { |
1348 |
// This handler wants the exception |
1349 |
break; |
1350 |
} |
1351 |
} |
1352 |
|
1353 |
if (portIndex >= oldExceptionPorts->maskCount) { |
1354 |
fprintf(stderr, "No handler for exception_type = %d. Not fowarding\n", exception_type); |
1355 |
return KERN_FAILURE; |
1356 |
} |
1357 |
|
1358 |
port = oldExceptionPorts->handlers[portIndex]; |
1359 |
behavior = oldExceptionPorts->behaviors[portIndex]; |
1360 |
flavor = oldExceptionPorts->flavors[portIndex]; |
1361 |
|
1362 |
/* |
1363 |
fprintf(stderr, "forwarding exception, port = 0x%x, behaviour = %d, flavor = %d\n", port, behavior, flavor); |
1364 |
*/ |
1365 |
|
1366 |
if (behavior != EXCEPTION_DEFAULT) { |
1367 |
thread_state_count = THREAD_STATE_MAX; |
1368 |
kret = thread_get_state (thread_port, flavor, thread_state, |
1369 |
&thread_state_count); |
1370 |
MACH_CHECK_ERROR (thread_get_state, kret); |
1371 |
} |
1372 |
|
1373 |
switch (behavior) { |
1374 |
case EXCEPTION_DEFAULT: |
1375 |
// fprintf(stderr, "forwarding to exception_raise\n"); |
1376 |
kret = exception_raise(port, thread_port, task_port, exception_type, |
1377 |
exception_data, data_count); |
1378 |
MACH_CHECK_ERROR (exception_raise, kret); |
1379 |
break; |
1380 |
case EXCEPTION_STATE: |
1381 |
// fprintf(stderr, "forwarding to exception_raise_state\n"); |
1382 |
kret = exception_raise_state(port, exception_type, exception_data, |
1383 |
data_count, &flavor, |
1384 |
thread_state, thread_state_count, |
1385 |
thread_state, &thread_state_count); |
1386 |
MACH_CHECK_ERROR (exception_raise_state, kret); |
1387 |
break; |
1388 |
case EXCEPTION_STATE_IDENTITY: |
1389 |
// fprintf(stderr, "forwarding to exception_raise_state_identity\n"); |
1390 |
kret = exception_raise_state_identity(port, thread_port, task_port, |
1391 |
exception_type, exception_data, |
1392 |
data_count, &flavor, |
1393 |
thread_state, thread_state_count, |
1394 |
thread_state, &thread_state_count); |
1395 |
MACH_CHECK_ERROR (exception_raise_state_identity, kret); |
1396 |
break; |
1397 |
default: |
1398 |
fprintf(stderr, "forward_exception got unknown behavior\n"); |
1399 |
break; |
1400 |
} |
1401 |
|
1402 |
if (behavior != EXCEPTION_DEFAULT) { |
1403 |
kret = thread_set_state (thread_port, flavor, thread_state, |
1404 |
thread_state_count); |
1405 |
MACH_CHECK_ERROR (thread_set_state, kret); |
1406 |
} |
1407 |
|
1408 |
return KERN_SUCCESS; |
1409 |
} |
1410 |
|
1411 |
/* |
1412 |
* This is the code that actually handles the exception. |
1413 |
* It is called by exc_server. For Darwin 5 Apple changed |
1414 |
* this a bit from how this family of functions worked in |
1415 |
* Mach. If you are familiar with that it is a little |
1416 |
* different. The main variation that concerns us here is |
1417 |
* that code is an array of exception specific codes and |
1418 |
* codeCount is a count of the number of codes in the code |
1419 |
* array. In typical Mach all exceptions have a code |
1420 |
* and sub-code. It happens to be the case that for a |
1421 |
* EXC_BAD_ACCESS exception the first entry is the type of |
1422 |
* bad access that occurred and the second entry is the |
1423 |
* faulting address so these entries correspond exactly to |
1424 |
* how the code and sub-code are used on Mach. |
1425 |
* |
1426 |
* This is a MIG interface. No code in Basilisk II should |
1427 |
* call this directley. This has to have external C |
1428 |
* linkage because that is what exc_server expects. |
1429 |
*/ |
1430 |
kern_return_t |
1431 |
catch_exception_raise(mach_port_t exception_port, |
1432 |
mach_port_t thread, |
1433 |
mach_port_t task, |
1434 |
exception_type_t exception, |
1435 |
exception_data_t code, |
1436 |
mach_msg_type_number_t codeCount) |
1437 |
{ |
1438 |
ppc_thread_state_t state; |
1439 |
kern_return_t krc; |
1440 |
|
1441 |
if ((exception == EXC_BAD_ACCESS) && (codeCount >= 2)) { |
1442 |
if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS)) |
1443 |
return KERN_SUCCESS; |
1444 |
} |
1445 |
|
1446 |
// In Mach we do not need to remove the exception handler. |
1447 |
// If we forward the exception, eventually some exception handler |
1448 |
// will take care of this exception. |
1449 |
krc = forward_exception(thread, task, exception, code, codeCount, &ports); |
1450 |
|
1451 |
return krc; |
1452 |
} |
1453 |
#endif |
1454 |
|
1455 |
#ifdef HAVE_SIGSEGV_RECOVERY |
1456 |
// Handle bad memory accesses with signal handler |
1457 |
static void sigsegv_handler(SIGSEGV_FAULT_HANDLER_ARGLIST) |
1458 |
{ |
1459 |
// Call handler and reinstall the global handler, if required |
1460 |
if (handle_badaccess(SIGSEGV_FAULT_HANDLER_ARGS)) { |
1461 |
#if (defined(HAVE_SIGACTION) ? defined(SIGACTION_NEED_REINSTALL) : defined(SIGNAL_NEED_REINSTALL)) |
1462 |
sigsegv_do_install_handler(sig); |
1463 |
#endif |
1464 |
return; |
1465 |
} |
1466 |
|
1467 |
// Failure: reinstall default handler for "safe" crash |
1468 |
#define FAULT_HANDLER(sig) signal(sig, SIG_DFL); |
1469 |
SIGSEGV_ALL_SIGNALS |
1470 |
#undef FAULT_HANDLER |
1471 |
} |
1472 |
#endif |
1473 |
|
1474 |
|
1475 |
/* |
1476 |
* SIGSEGV handler initialization |
1477 |
*/ |
1478 |
|
1479 |
#if defined(HAVE_SIGINFO_T) |
1480 |
static bool sigsegv_do_install_handler(int sig) |
1481 |
{ |
1482 |
// Setup SIGSEGV handler to process writes to frame buffer |
1483 |
#ifdef HAVE_SIGACTION |
1484 |
struct sigaction sigsegv_sa; |
1485 |
sigemptyset(&sigsegv_sa.sa_mask); |
1486 |
sigsegv_sa.sa_sigaction = sigsegv_handler; |
1487 |
sigsegv_sa.sa_flags = SA_SIGINFO; |
1488 |
return (sigaction(sig, &sigsegv_sa, 0) == 0); |
1489 |
#else |
1490 |
return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR); |
1491 |
#endif |
1492 |
} |
1493 |
#endif |
1494 |
|
1495 |
#if defined(HAVE_SIGCONTEXT_SUBTERFUGE) |
1496 |
static bool sigsegv_do_install_handler(int sig) |
1497 |
{ |
1498 |
// Setup SIGSEGV handler to process writes to frame buffer |
1499 |
#ifdef HAVE_SIGACTION |
1500 |
struct sigaction sigsegv_sa; |
1501 |
sigemptyset(&sigsegv_sa.sa_mask); |
1502 |
sigsegv_sa.sa_handler = (signal_handler)sigsegv_handler; |
1503 |
sigsegv_sa.sa_flags = 0; |
1504 |
#if !EMULATED_68K && defined(__NetBSD__) |
1505 |
sigaddset(&sigsegv_sa.sa_mask, SIGALRM); |
1506 |
sigsegv_sa.sa_flags |= SA_ONSTACK; |
1507 |
#endif |
1508 |
return (sigaction(sig, &sigsegv_sa, 0) == 0); |
1509 |
#else |
1510 |
return (signal(sig, (signal_handler)sigsegv_handler) != SIG_ERR); |
1511 |
#endif |
1512 |
} |
1513 |
#endif |
1514 |
|
1515 |
#if defined(HAVE_MACH_EXCEPTIONS) |
1516 |
static bool sigsegv_do_install_handler(sigsegv_fault_handler_t handler) |
1517 |
{ |
1518 |
/* |
1519 |
* Except for the exception port functions, this should be |
1520 |
* pretty much stock Mach. If later you choose to support |
1521 |
* other Mach's besides Darwin, just check for __MACH__ |
1522 |
* here and __APPLE__ where the actual differences are. |
1523 |
*/ |
1524 |
#if defined(__APPLE__) && defined(__MACH__) |
1525 |
if (sigsegv_fault_handler != NULL) { |
1526 |
sigsegv_fault_handler = handler; |
1527 |
return true; |
1528 |
} |
1529 |
|
1530 |
kern_return_t krc; |
1531 |
|
1532 |
// create the the exception port |
1533 |
krc = mach_port_allocate(mach_task_self(), |
1534 |
MACH_PORT_RIGHT_RECEIVE, &_exceptionPort); |
1535 |
if (krc != KERN_SUCCESS) { |
1536 |
mach_error("mach_port_allocate", krc); |
1537 |
return false; |
1538 |
} |
1539 |
|
1540 |
// add a port send right |
1541 |
krc = mach_port_insert_right(mach_task_self(), |
1542 |
_exceptionPort, _exceptionPort, |
1543 |
MACH_MSG_TYPE_MAKE_SEND); |
1544 |
if (krc != KERN_SUCCESS) { |
1545 |
mach_error("mach_port_insert_right", krc); |
1546 |
return false; |
1547 |
} |
1548 |
|
1549 |
// get the old exception ports |
1550 |
ports.maskCount = sizeof (ports.masks) / sizeof (ports.masks[0]); |
1551 |
krc = thread_get_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, ports.masks, |
1552 |
&ports.maskCount, ports.handlers, ports.behaviors, ports.flavors); |
1553 |
if (krc != KERN_SUCCESS) { |
1554 |
mach_error("thread_get_exception_ports", krc); |
1555 |
return false; |
1556 |
} |
1557 |
|
1558 |
// set the new exception port |
1559 |
// |
1560 |
// We could have used EXCEPTION_STATE_IDENTITY instead of |
1561 |
// EXCEPTION_DEFAULT to get the thread state in the initial |
1562 |
// message, but it turns out that in the common case this is not |
1563 |
// neccessary. If we need it we can later ask for it from the |
1564 |
// suspended thread. |
1565 |
// |
1566 |
// Even with THREAD_STATE_NONE, Darwin provides the program |
1567 |
// counter in the thread state. The comments in the header file |
1568 |
// seem to imply that you can count on the GPR's on an exception |
1569 |
// as well but just to be safe I use MACHINE_THREAD_STATE because |
1570 |
// you have to ask for all of the GPR's anyway just to get the |
1571 |
// program counter. In any case because of update effective |
1572 |
// address from immediate and update address from effective |
1573 |
// addresses of ra and rb modes (as good an name as any for these |
1574 |
// addressing modes) used in PPC instructions, you will need the |
1575 |
// GPR state anyway. |
1576 |
krc = thread_set_exception_ports(mach_thread_self(), EXC_MASK_BAD_ACCESS, _exceptionPort, |
1577 |
EXCEPTION_DEFAULT, MACHINE_THREAD_STATE); |
1578 |
if (krc != KERN_SUCCESS) { |
1579 |
mach_error("thread_set_exception_ports", krc); |
1580 |
return false; |
1581 |
} |
1582 |
|
1583 |
// create the exception handler thread |
1584 |
if (pthread_create(&exc_thread, NULL, &handleExceptions, NULL) != 0) { |
1585 |
(void)fprintf(stderr, "creation of exception thread failed\n"); |
1586 |
return false; |
1587 |
} |
1588 |
|
1589 |
// do not care about the exception thread any longer, let is run standalone |
1590 |
(void)pthread_detach(exc_thread); |
1591 |
|
1592 |
sigsegv_fault_handler = handler; |
1593 |
return true; |
1594 |
#else |
1595 |
return false; |
1596 |
#endif |
1597 |
} |
1598 |
#endif |
1599 |
|
1600 |
bool sigsegv_install_handler(sigsegv_fault_handler_t handler) |
1601 |
{ |
1602 |
#if defined(HAVE_SIGSEGV_RECOVERY) |
1603 |
bool success = true; |
1604 |
#define FAULT_HANDLER(sig) success = success && sigsegv_do_install_handler(sig); |
1605 |
SIGSEGV_ALL_SIGNALS |
1606 |
#undef FAULT_HANDLER |
1607 |
if (success) |
1608 |
sigsegv_fault_handler = handler; |
1609 |
return success; |
1610 |
#elif defined(HAVE_MACH_EXCEPTIONS) |
1611 |
return sigsegv_do_install_handler(handler); |
1612 |
#else |
1613 |
// FAIL: no siginfo_t nor sigcontext subterfuge is available |
1614 |
return false; |
1615 |
#endif |
1616 |
} |
1617 |
|
1618 |
|
1619 |
/* |
1620 |
* SIGSEGV handler deinitialization |
1621 |
*/ |
1622 |
|
1623 |
void sigsegv_deinstall_handler(void) |
1624 |
{ |
1625 |
// We do nothing for Mach exceptions, the thread would need to be |
1626 |
// suspended if not already so, and we might mess with other |
1627 |
// exception handlers that came after we registered ours. There is |
1628 |
// no need to remove the exception handler, in fact this function is |
1629 |
// not called anywhere in Basilisk II. |
1630 |
#ifdef HAVE_SIGSEGV_RECOVERY |
1631 |
sigsegv_fault_handler = 0; |
1632 |
#define FAULT_HANDLER(sig) signal(sig, SIG_DFL); |
1633 |
SIGSEGV_ALL_SIGNALS |
1634 |
#undef FAULT_HANDLER |
1635 |
#endif |
1636 |
} |
1637 |
|
1638 |
|
1639 |
/* |
1640 |
* Set callback function when we cannot handle the fault |
1641 |
*/ |
1642 |
|
1643 |
void sigsegv_set_dump_state(sigsegv_state_dumper_t handler) |
1644 |
{ |
1645 |
sigsegv_state_dumper = handler; |
1646 |
} |
1647 |
|
1648 |
|
1649 |
/* |
1650 |
* Test program used for configure/test |
1651 |
*/ |
1652 |
|
1653 |
#ifdef CONFIGURE_TEST_SIGSEGV_RECOVERY |
1654 |
#include <stdio.h> |
1655 |
#include <stdlib.h> |
1656 |
#include <fcntl.h> |
1657 |
#include <sys/mman.h> |
1658 |
#include "vm_alloc.h" |
1659 |
|
1660 |
const int REF_INDEX = 123; |
1661 |
const int REF_VALUE = 45; |
1662 |
|
1663 |
static int page_size; |
1664 |
static volatile char * page = 0; |
1665 |
static volatile int handler_called = 0; |
1666 |
|
1667 |
#ifdef __GNUC__ |
1668 |
// Code range where we expect the fault to come from |
1669 |
static void *b_region, *e_region; |
1670 |
#endif |
1671 |
|
1672 |
static sigsegv_return_t sigsegv_test_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address) |
1673 |
{ |
1674 |
#if DEBUG |
1675 |
printf("sigsegv_test_handler(%p, %p)\n", fault_address, instruction_address); |
1676 |
printf("expected fault at %p\n", page + REF_INDEX); |
1677 |
#ifdef __GNUC__ |
1678 |
printf("expected instruction address range: %p-%p\n", b_region, e_region); |
1679 |
#endif |
1680 |
#endif |
1681 |
handler_called++; |
1682 |
if ((fault_address - REF_INDEX) != page) |
1683 |
exit(10); |
1684 |
#ifdef __GNUC__ |
1685 |
// Make sure reported fault instruction address falls into |
1686 |
// expected code range |
1687 |
if (instruction_address != SIGSEGV_INVALID_PC |
1688 |
&& ((instruction_address < (sigsegv_address_t)b_region) || |
1689 |
(instruction_address >= (sigsegv_address_t)e_region))) |
1690 |
exit(11); |
1691 |
#endif |
1692 |
if (vm_protect((char *)((unsigned long)fault_address & -page_size), page_size, VM_PAGE_READ | VM_PAGE_WRITE) != 0) |
1693 |
exit(12); |
1694 |
return SIGSEGV_RETURN_SUCCESS; |
1695 |
} |
1696 |
|
1697 |
#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION |
1698 |
static sigsegv_return_t sigsegv_insn_handler(sigsegv_address_t fault_address, sigsegv_address_t instruction_address) |
1699 |
{ |
1700 |
if (((unsigned long)fault_address - (unsigned long)page) < page_size) { |
1701 |
#ifdef __GNUC__ |
1702 |
// Make sure reported fault instruction address falls into |
1703 |
// expected code range |
1704 |
if (instruction_address != SIGSEGV_INVALID_PC |
1705 |
&& ((instruction_address < (sigsegv_address_t)b_region) || |
1706 |
(instruction_address >= (sigsegv_address_t)e_region))) |
1707 |
return SIGSEGV_RETURN_FAILURE; |
1708 |
#endif |
1709 |
return SIGSEGV_RETURN_SKIP_INSTRUCTION; |
1710 |
} |
1711 |
|
1712 |
return SIGSEGV_RETURN_FAILURE; |
1713 |
} |
1714 |
|
1715 |
// More sophisticated tests for instruction skipper |
1716 |
static bool arch_insn_skipper_tests() |
1717 |
{ |
1718 |
#if (defined(i386) || defined(__i386__)) || defined(__x86_64__) |
1719 |
static const unsigned char code[] = { |
1720 |
0x8a, 0x00, // mov (%eax),%al |
1721 |
0x8a, 0x2c, 0x18, // mov (%eax,%ebx,1),%ch |
1722 |
0x88, 0x20, // mov %ah,(%eax) |
1723 |
0x88, 0x08, // mov %cl,(%eax) |
1724 |
0x66, 0x8b, 0x00, // mov (%eax),%ax |
1725 |
0x66, 0x8b, 0x0c, 0x18, // mov (%eax,%ebx,1),%cx |
1726 |
0x66, 0x89, 0x00, // mov %ax,(%eax) |
1727 |
0x66, 0x89, 0x0c, 0x18, // mov %cx,(%eax,%ebx,1) |
1728 |
0x8b, 0x00, // mov (%eax),%eax |
1729 |
0x8b, 0x0c, 0x18, // mov (%eax,%ebx,1),%ecx |
1730 |
0x89, 0x00, // mov %eax,(%eax) |
1731 |
0x89, 0x0c, 0x18, // mov %ecx,(%eax,%ebx,1) |
1732 |
#if defined(__x86_64__) |
1733 |
0x44, 0x8a, 0x00, // mov (%rax),%r8b |
1734 |
0x44, 0x8a, 0x20, // mov (%rax),%r12b |
1735 |
0x42, 0x8a, 0x3c, 0x10, // mov (%rax,%r10,1),%dil |
1736 |
0x44, 0x88, 0x00, // mov %r8b,(%rax) |
1737 |
0x44, 0x88, 0x20, // mov %r12b,(%rax) |
1738 |
0x42, 0x88, 0x3c, 0x10, // mov %dil,(%rax,%r10,1) |
1739 |
0x66, 0x44, 0x8b, 0x00, // mov (%rax),%r8w |
1740 |
0x66, 0x42, 0x8b, 0x0c, 0x10, // mov (%rax,%r10,1),%cx |
1741 |
0x66, 0x44, 0x89, 0x00, // mov %r8w,(%rax) |
1742 |
0x66, 0x42, 0x89, 0x0c, 0x10, // mov %cx,(%rax,%r10,1) |
1743 |
0x44, 0x8b, 0x00, // mov (%rax),%r8d |
1744 |
0x42, 0x8b, 0x0c, 0x10, // mov (%rax,%r10,1),%ecx |
1745 |
0x44, 0x89, 0x00, // mov %r8d,(%rax) |
1746 |
0x42, 0x89, 0x0c, 0x10, // mov %ecx,(%rax,%r10,1) |
1747 |
0x48, 0x8b, 0x08, // mov (%rax),%rcx |
1748 |
0x4c, 0x8b, 0x18, // mov (%rax),%r11 |
1749 |
0x4a, 0x8b, 0x0c, 0x10, // mov (%rax,%r10,1),%rcx |
1750 |
0x4e, 0x8b, 0x1c, 0x10, // mov (%rax,%r10,1),%r11 |
1751 |
0x48, 0x89, 0x08, // mov %rcx,(%rax) |
1752 |
0x4c, 0x89, 0x18, // mov %r11,(%rax) |
1753 |
0x4a, 0x89, 0x0c, 0x10, // mov %rcx,(%rax,%r10,1) |
1754 |
0x4e, 0x89, 0x1c, 0x10, // mov %r11,(%rax,%r10,1) |
1755 |
#endif |
1756 |
0 // end |
1757 |
}; |
1758 |
const int N_REGS = 20; |
1759 |
unsigned long regs[N_REGS]; |
1760 |
for (int i = 0; i < N_REGS; i++) |
1761 |
regs[i] = i; |
1762 |
const unsigned long start_code = (unsigned long)&code; |
1763 |
regs[X86_REG_EIP] = start_code; |
1764 |
while ((regs[X86_REG_EIP] - start_code) < (sizeof(code) - 1) |
1765 |
&& ix86_skip_instruction(regs)) |
1766 |
; /* simply iterate */ |
1767 |
return (regs[X86_REG_EIP] - start_code) == (sizeof(code) - 1); |
1768 |
#endif |
1769 |
return true; |
1770 |
} |
1771 |
#endif |
1772 |
|
1773 |
int main(void) |
1774 |
{ |
1775 |
if (vm_init() < 0) |
1776 |
return 1; |
1777 |
|
1778 |
page_size = getpagesize(); |
1779 |
if ((page = (char *)vm_acquire(page_size)) == VM_MAP_FAILED) |
1780 |
return 2; |
1781 |
|
1782 |
memset((void *)page, 0, page_size); |
1783 |
if (vm_protect((char *)page, page_size, VM_PAGE_READ) < 0) |
1784 |
return 3; |
1785 |
|
1786 |
if (!sigsegv_install_handler(sigsegv_test_handler)) |
1787 |
return 4; |
1788 |
|
1789 |
#ifdef __GNUC__ |
1790 |
b_region = &&L_b_region1; |
1791 |
e_region = &&L_e_region1; |
1792 |
#endif |
1793 |
L_b_region1: |
1794 |
page[REF_INDEX] = REF_VALUE; |
1795 |
if (page[REF_INDEX] != REF_VALUE) |
1796 |
exit(20); |
1797 |
page[REF_INDEX] = REF_VALUE; |
1798 |
L_e_region1: |
1799 |
|
1800 |
if (handler_called != 1) |
1801 |
return 5; |
1802 |
|
1803 |
#ifdef HAVE_SIGSEGV_SKIP_INSTRUCTION |
1804 |
if (!sigsegv_install_handler(sigsegv_insn_handler)) |
1805 |
return 6; |
1806 |
|
1807 |
if (vm_protect((char *)page, page_size, VM_PAGE_READ | VM_PAGE_WRITE) < 0) |
1808 |
return 7; |
1809 |
|
1810 |
for (int i = 0; i < page_size; i++) |
1811 |
page[i] = (i + 1) % page_size; |
1812 |
|
1813 |
if (vm_protect((char *)page, page_size, VM_PAGE_NOACCESS) < 0) |
1814 |
return 8; |
1815 |
|
1816 |
#define TEST_SKIP_INSTRUCTION(TYPE) do { \ |
1817 |
const unsigned long TAG = 0x12345678 | \ |
1818 |
(sizeof(long) == 8 ? 0x9abcdef0UL << 31 : 0); \ |
1819 |
TYPE data = *((TYPE *)(page + sizeof(TYPE))); \ |
1820 |
volatile unsigned long effect = data + TAG; \ |
1821 |
if (effect != TAG) \ |
1822 |
return 9; \ |
1823 |
} while (0) |
1824 |
|
1825 |
#ifdef __GNUC__ |
1826 |
b_region = &&L_b_region2; |
1827 |
e_region = &&L_e_region2; |
1828 |
#endif |
1829 |
L_b_region2: |
1830 |
TEST_SKIP_INSTRUCTION(unsigned char); |
1831 |
TEST_SKIP_INSTRUCTION(unsigned short); |
1832 |
TEST_SKIP_INSTRUCTION(unsigned int); |
1833 |
TEST_SKIP_INSTRUCTION(unsigned long); |
1834 |
L_e_region2: |
1835 |
|
1836 |
if (!arch_insn_skipper_tests()) |
1837 |
return 20; |
1838 |
#endif |
1839 |
|
1840 |
vm_exit(); |
1841 |
return 0; |
1842 |
} |
1843 |
#endif |