diff options
Diffstat (limited to 'sysdeps/nios2/dl-trampoline.S')
| -rw-r--r-- | sysdeps/nios2/dl-trampoline.S | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/sysdeps/nios2/dl-trampoline.S b/sysdeps/nios2/dl-trampoline.S new file mode 100644 index 0000000000..e4a3f7060f --- /dev/null +++ b/sysdeps/nios2/dl-trampoline.S @@ -0,0 +1,79 @@ +/* PLT trampolines. Nios II version. + Copyright (C) 2005-2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library. If not, see + <http://www.gnu.org/licenses/>. */ + +#include <sysdep.h> +#include <libc-symbols.h> + + .text + .globl _dl_runtime_resolve + cfi_startproc +_dl_runtime_resolve: +/* The runtime resolver receives the original function arguments in r4 + through r7, the shared library identifier from GOT[1]? in r14, and the + relocation index times four in r15. It updates the corresponding PLT GOT + entry so that the PLT entry will transfer control directly to the target + in the future, and then transfers control to the target. */ + /* Save arguments and return address. */ + subi sp, sp, 28 + cfi_adjust_cfa_offset (28) + stw r22, 24(sp) + cfi_rel_offset (r22, 24) + stw r8, 20(sp) /* save r8, because this might be a call to mcount */ + cfi_rel_offset (r8, 20) + stw r7, 16(sp) + cfi_rel_offset (r7, 16) + stw r6, 12(sp) + cfi_rel_offset (r6, 12) + stw r5, 8(sp) + cfi_rel_offset (r5, 8) + stw r4, 4(sp) + cfi_rel_offset (r4, 4) + stw ra, 0(sp) + cfi_rel_offset (ra, 0) + + /* Get pointer to linker struct. */ + mov r4, r14 + + /* Get the relocation offset. We're given a multiple of 4 and + need a multiple of 12, so multiply by 3. */ + slli r5, r15, 1 + add r5, r5, r15 + + /* Call the fixup routine. */ + nextpc r22 +1: movhi r2, %hiadj(_gp_got - 1b) + addi r2, r2, %lo(_gp_got - 1b) + add r22, r22, r2 + ldw r2, %call(_dl_fixup)(r22) + callr r2 + + /* Restore the arguments and return address. */ + ldw ra, 0(sp) + ldw r4, 4(sp) + ldw r5, 8(sp) + ldw r6, 12(sp) + ldw r7, 16(sp) + ldw r8, 20(sp) + ldw r22, 24(sp) + addi sp, sp, 28 + cfi_adjust_cfa_offset (-28) + + /* Jump to the newly found address. */ + jmp r2 + + cfi_endproc |