| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include <private/bionic_asm.h> |
| |
| // gdb is smart enough to unwind through signal frames with just the regular |
| // CFI information but libgcc and libunwind both need extra help. We do this |
| // by using .fnstart/.fnend and inserting a nop before both __restore and |
| // __restore_rt (but covered by the .fnstart/.fnend) so that although they're |
| // not inside the functions from objdump's point of view, an unwinder that |
| // blindly looks at the previous instruction (but is then smart enough to check |
| // the unwind information to find out where it landed) gets the right answer. |
| // Make sure not to have both DWARF and ARM unwind information, so only |
| // use the ARM unwind information. |
| |
| // We need to place .fnstart ourselves (but we may as well keep the free .fnend). |
| #undef __bionic_asm_custom_entry |
| #define __bionic_asm_custom_entry(f) |
| |
| .fnstart |
| .save {r0-r15} |
| .pad #32 |
| nop |
| ENTRY_PRIVATE_NO_DWARF(__restore) |
| // This function must have exactly this instruction sequence. |
| mov r7, #__NR_sigreturn |
| swi #0 |
| END_NO_DWARF(__restore) |
| |
| .fnstart |
| .save {r0-r15} |
| .pad #160 |
| nop |
| ENTRY_PRIVATE_NO_DWARF(__restore_rt) |
| // This function must have exactly this instruction sequence. |
| mov r7, #__NR_rt_sigreturn |
| swi #0 |
| END_NO_DWARF(__restore_rt) |