| /* Stack-aligning implementation of __tls_get_addr. x86-64 version. |
| Copyright (C) 2017-2018 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/>. */ |
| |
| #ifdef SHARED |
| |
| # include <sysdep.h> |
| # include "tlsdesc.h" |
| # include "rtld-offsets.h" |
| |
| /* See __tls_get_addr and __tls_get_addr_slow in dl-tls.c. This function |
| call __tls_get_addr_slow on both slow paths. It realigns the stack |
| before the call to work around GCC PR58066. */ |
| |
| ENTRY (__tls_get_addr) |
| mov %fs:DTV_OFFSET, %RDX_LP |
| mov GL_TLS_GENERATION_OFFSET+_rtld_local(%rip), %RAX_LP |
| /* GL(dl_tls_generation) == dtv[0].counter */ |
| cmp %RAX_LP, (%rdx) |
| jne 1f |
| mov TI_MODULE_OFFSET(%rdi), %RAX_LP |
| /* dtv[ti->ti_module] */ |
| # ifdef __LP64__ |
| salq $4, %rax |
| movq (%rdx,%rax), %rax |
| # else |
| movl (%rdx,%rax, 8), %eax |
| # endif |
| cmp $-1, %RAX_LP |
| je 1f |
| add TI_OFFSET_OFFSET(%rdi), %RAX_LP |
| ret |
| 1: |
| /* On the slow path, align the stack. */ |
| pushq %rbp |
| cfi_def_cfa_offset (16) |
| cfi_offset (%rbp, -16) |
| mov %RSP_LP, %RBP_LP |
| cfi_def_cfa_register (%rbp) |
| and $-16, %RSP_LP |
| call __tls_get_addr_slow |
| mov %RBP_LP, %RSP_LP |
| popq %rbp |
| cfi_def_cfa (%rsp, 8) |
| ret |
| END (__tls_get_addr) |
| #endif /* SHARED */ |
