diff options
Diffstat (limited to 'sysdeps/x86_64/dl-tlsdesc.S')
| -rw-r--r-- | sysdeps/x86_64/dl-tlsdesc.S | 245 |
1 files changed, 0 insertions, 245 deletions
diff --git a/sysdeps/x86_64/dl-tlsdesc.S b/sysdeps/x86_64/dl-tlsdesc.S deleted file mode 100644 index be3a780a1a..0000000000 --- a/sysdeps/x86_64/dl-tlsdesc.S +++ /dev/null @@ -1,245 +0,0 @@ -/* Thread-local storage handling in the ELF dynamic linker. x86_64 version. - Copyright (C) 2004-2017 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 <tls.h> -#include "tlsdesc.h" - - .text - - /* This function is used to compute the TP offset for symbols in - Static TLS, i.e., whose TP offset is the same for all - threads. - - The incoming %rax points to the TLS descriptor, such that - 0(%rax) points to _dl_tlsdesc_return itself, and 8(%rax) holds - the TP offset of the symbol corresponding to the object - denoted by the argument. */ - - .hidden _dl_tlsdesc_return - .global _dl_tlsdesc_return - .type _dl_tlsdesc_return,@function - cfi_startproc - .align 16 -_dl_tlsdesc_return: - movq 8(%rax), %rax - ret - cfi_endproc - .size _dl_tlsdesc_return, .-_dl_tlsdesc_return - - /* This function is used for undefined weak TLS symbols, for - which the base address (i.e., disregarding any addend) should - resolve to NULL. - - %rax points to the TLS descriptor, such that 0(%rax) points to - _dl_tlsdesc_undefweak itself, and 8(%rax) holds the addend. - We return the addend minus the TP, such that, when the caller - adds TP, it gets the addend back. If that's zero, as usual, - that's most likely a NULL pointer. */ - - .hidden _dl_tlsdesc_undefweak - .global _dl_tlsdesc_undefweak - .type _dl_tlsdesc_undefweak,@function - cfi_startproc - .align 16 -_dl_tlsdesc_undefweak: - movq 8(%rax), %rax - subq %fs:0, %rax - ret - cfi_endproc - .size _dl_tlsdesc_undefweak, .-_dl_tlsdesc_undefweak - -#ifdef SHARED - .hidden _dl_tlsdesc_dynamic - .global _dl_tlsdesc_dynamic - .type _dl_tlsdesc_dynamic,@function - - /* %rax points to the TLS descriptor, such that 0(%rax) points to - _dl_tlsdesc_dynamic itself, and 8(%rax) points to a struct - tlsdesc_dynamic_arg object. It must return in %rax the offset - between the thread pointer and the object denoted by the - argument, without clobbering any registers. - - The assembly code that follows is a rendition of the following - C code, hand-optimized a little bit. - -ptrdiff_t -_dl_tlsdesc_dynamic (register struct tlsdesc *tdp asm ("%rax")) -{ - struct tlsdesc_dynamic_arg *td = tdp->arg; - dtv_t *dtv = *(dtv_t **)((char *)__thread_pointer + DTV_OFFSET); - if (__builtin_expect (td->gen_count <= dtv[0].counter - && (dtv[td->tlsinfo.ti_module].pointer.val - != TLS_DTV_UNALLOCATED), - 1)) - return dtv[td->tlsinfo.ti_module].pointer.val + td->tlsinfo.ti_offset - - __thread_pointer; - - return __tls_get_addr_internal (&td->tlsinfo) - __thread_pointer; -} -*/ - cfi_startproc - .align 16 -_dl_tlsdesc_dynamic: - /* Preserve call-clobbered registers that we modify. - We need two scratch regs anyway. */ - movq %rsi, -16(%rsp) - movq %fs:DTV_OFFSET, %rsi - movq %rdi, -8(%rsp) - movq TLSDESC_ARG(%rax), %rdi - movq (%rsi), %rax - cmpq %rax, TLSDESC_GEN_COUNT(%rdi) - ja .Lslow - movq TLSDESC_MODID(%rdi), %rax - salq $4, %rax - movq (%rax,%rsi), %rax - cmpq $-1, %rax - je .Lslow - addq TLSDESC_MODOFF(%rdi), %rax -.Lret: - movq -16(%rsp), %rsi - subq %fs:0, %rax - movq -8(%rsp), %rdi - ret -.Lslow: - /* Besides rdi and rsi, saved above, save rdx, rcx, r8, r9, - r10 and r11. Also, align the stack, that's off by 8 bytes. */ - subq $72, %rsp - cfi_adjust_cfa_offset (72) - movq %rdx, 8(%rsp) - movq %rcx, 16(%rsp) - movq %r8, 24(%rsp) - movq %r9, 32(%rsp) - movq %r10, 40(%rsp) - movq %r11, 48(%rsp) - /* %rdi already points to the tlsinfo data structure. */ - call HIDDEN_JUMPTARGET (__tls_get_addr) - movq 8(%rsp), %rdx - movq 16(%rsp), %rcx - movq 24(%rsp), %r8 - movq 32(%rsp), %r9 - movq 40(%rsp), %r10 - movq 48(%rsp), %r11 - addq $72, %rsp - cfi_adjust_cfa_offset (-72) - jmp .Lret - cfi_endproc - .size _dl_tlsdesc_dynamic, .-_dl_tlsdesc_dynamic -#endif /* SHARED */ - - /* This function is a wrapper for a lazy resolver for TLS_DESC - RELA relocations. The incoming 0(%rsp) points to the caller's - link map, pushed by the dynamic object's internal lazy TLS - resolver front-end before tail-calling us. We need to pop it - ourselves. %rax points to a TLS descriptor, such that 0(%rax) - holds the address of the internal resolver front-end (unless - some other thread beat us to resolving it) and 8(%rax) holds a - pointer to the relocation. - - When the actual resolver returns, it will have adjusted the - TLS descriptor such that we can tail-call it for it to return - the TP offset of the symbol. */ - - .hidden _dl_tlsdesc_resolve_rela - .global _dl_tlsdesc_resolve_rela - .type _dl_tlsdesc_resolve_rela,@function - cfi_startproc - .align 16 - /* The PLT entry will have pushed the link_map pointer. */ -_dl_tlsdesc_resolve_rela: - cfi_adjust_cfa_offset (8) - /* Save all call-clobbered registers. Add 8 bytes for push in - the PLT entry to align the stack. */ - subq $80, %rsp - cfi_adjust_cfa_offset (80) - movq %rax, (%rsp) - movq %rdi, 8(%rsp) - movq %rax, %rdi /* Pass tlsdesc* in %rdi. */ - movq %rsi, 16(%rsp) - movq 80(%rsp), %rsi /* Pass link_map* in %rsi. */ - movq %r8, 24(%rsp) - movq %r9, 32(%rsp) - movq %r10, 40(%rsp) - movq %r11, 48(%rsp) - movq %rdx, 56(%rsp) - movq %rcx, 64(%rsp) - call _dl_tlsdesc_resolve_rela_fixup - movq (%rsp), %rax - movq 8(%rsp), %rdi - movq 16(%rsp), %rsi - movq 24(%rsp), %r8 - movq 32(%rsp), %r9 - movq 40(%rsp), %r10 - movq 48(%rsp), %r11 - movq 56(%rsp), %rdx - movq 64(%rsp), %rcx - addq $88, %rsp - cfi_adjust_cfa_offset (-88) - jmp *(%rax) - cfi_endproc - .size _dl_tlsdesc_resolve_rela, .-_dl_tlsdesc_resolve_rela - - /* This function is a placeholder for lazy resolving of TLS - relocations. Once some thread starts resolving a TLS - relocation, it sets up the TLS descriptor to use this - resolver, such that other threads that would attempt to - resolve it concurrently may skip the call to the original lazy - resolver and go straight to a condition wait. - - When the actual resolver returns, it will have adjusted the - TLS descriptor such that we can tail-call it for it to return - the TP offset of the symbol. */ - - .hidden _dl_tlsdesc_resolve_hold - .global _dl_tlsdesc_resolve_hold - .type _dl_tlsdesc_resolve_hold,@function - cfi_startproc - .align 16 -_dl_tlsdesc_resolve_hold: -0: - /* Save all call-clobbered registers. */ - subq $72, %rsp - cfi_adjust_cfa_offset (72) - movq %rax, (%rsp) - movq %rdi, 8(%rsp) - movq %rax, %rdi /* Pass tlsdesc* in %rdi. */ - movq %rsi, 16(%rsp) - /* Pass _dl_tlsdesc_resolve_hold's address in %rsi. */ - leaq . - _dl_tlsdesc_resolve_hold(%rip), %rsi - movq %r8, 24(%rsp) - movq %r9, 32(%rsp) - movq %r10, 40(%rsp) - movq %r11, 48(%rsp) - movq %rdx, 56(%rsp) - movq %rcx, 64(%rsp) - call _dl_tlsdesc_resolve_hold_fixup -1: - movq (%rsp), %rax - movq 8(%rsp), %rdi - movq 16(%rsp), %rsi - movq 24(%rsp), %r8 - movq 32(%rsp), %r9 - movq 40(%rsp), %r10 - movq 48(%rsp), %r11 - movq 56(%rsp), %rdx - movq 64(%rsp), %rcx - addq $72, %rsp - cfi_adjust_cfa_offset (-72) - jmp *(%rax) - cfi_endproc - .size _dl_tlsdesc_resolve_hold, .-_dl_tlsdesc_resolve_hold |