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authorJoseph Myers <joseph@codesourcery.com>2014-02-08 01:49:39 +0000
committerJoseph Myers <joseph@codesourcery.com>2014-02-08 01:49:39 +0000
commitc6bfe5c4d756913297db03f55e42016d1c48918c (patch)
tree898d2910ef903f46b596ad54e519ed4495357766 /sysdeps/arm/dl-tlsdesc.S
parent852fa2dd3aa1a687780e27300df9eb0bdc433863 (diff)
Move arm from ports to libc.
I've moved the ARM port from ports to the main sysdeps hierarchy. Beyond the README update, the move of the files was simply git mv ports/sysdeps/arm sysdeps/arm git mv ports/sysdeps/unix/arm sysdeps/unix/arm git mv ports/sysdeps/unix/sysv/linux/arm sysdeps/unix/sysv/linux/arm and in addition to the ChangeLog entries here, I put a note at the top of ports/ChangeLog.arm similar to that at the top of ChangeLog.powerpc. There is deliberately no NEWS change, as I think it makes the most sense to put in a general note above all ports having moved if we can achieve that for 2.20. Tested that disassembly of installed shared libraries for arm is the same before and after this patch, except for data (not instructions) in ld.so (there are assertions in sysdeps/arm/dl-machine.h, and the path by which that file is found, and so by which it appears in the assertion message, changes as a result of the move). * sysdeps/arm: Move directory from ports/sysdeps/arm. * sysdeps/unix/arm: Move directory from ports/sysdeps/unix/arm. * sysdeps/unix/sysv/linux/arm: Move directory from ports/sysdeps/unix/sysv/linux/arm. * README: Update listing for arm-*-linux-gnueabi. ports/ChangeLog.arm: * sysdeps/arm: Move directory to ../sysdeps/arm. * sysdeps/unix/arm: Move directory to ../sysdeps.arm. * sysdeps/unix/sysv/linux/arm: Move directory to ../sysdeps/unix/sysv/linux/arm.
Diffstat (limited to 'sysdeps/arm/dl-tlsdesc.S')
-rw-r--r--sysdeps/arm/dl-tlsdesc.S226
1 files changed, 226 insertions, 0 deletions
diff --git a/sysdeps/arm/dl-tlsdesc.S b/sysdeps/arm/dl-tlsdesc.S
new file mode 100644
index 0000000000..1644a32793
--- /dev/null
+++ b/sysdeps/arm/dl-tlsdesc.S
@@ -0,0 +1,226 @@
+/* Thread-local storage handling in the ELF dynamic linker. ARM version.
+ Copyright (C) 2006-2014 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 <arm-features.h>
+#include <tls.h>
+#include "tlsdesc.h"
+
+ .text
+ @ emit debug information with cfi
+ @ use arm-specific pseudos for unwinding itself
+ CFI_SECTIONS
+ .hidden _dl_tlsdesc_return
+ .global _dl_tlsdesc_return
+ .type _dl_tlsdesc_return,#function
+ cfi_startproc
+ eabi_fnstart
+ .align 2
+_dl_tlsdesc_return:
+ sfi_breg r0, \
+ ldr r0, [\B]
+ BX (lr)
+ eabi_fnend
+ cfi_endproc
+ .size _dl_tlsdesc_return, .-_dl_tlsdesc_return
+
+ .hidden _dl_tlsdesc_undefweak
+ .global _dl_tlsdesc_undefweak
+ .type _dl_tlsdesc_undefweak,#function
+ cfi_startproc
+ eabi_fnstart
+ .align 2
+_dl_tlsdesc_undefweak:
+ GET_TLS (r1)
+ rsb r0, r0, #0
+ BX (lr)
+ cfi_endproc
+ eabi_fnend
+ .size _dl_tlsdesc_undefweak, .-_dl_tlsdesc_undefweak
+
+#ifdef SHARED
+ .hidden _dl_tlsdesc_dynamic
+ .global _dl_tlsdesc_dynamic
+ .type _dl_tlsdesc_dynamic,#function
+
+
+/*
+ The assembly code that follows is a rendition of the following
+ C code, hand-optimized a little bit.
+
+ptrdiff_t
+_dl_tlsdesc_dynamic(struct tlsdesc *tdp)
+{
+ struct tlsdesc_dynamic_arg *td = tdp->argument.pointer;
+ dtv_t *dtv = (dtv_t *)THREAD_DTV();
+ 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 - __builtin_thread_pointer();
+
+ return __tls_get_addr (&td->tlsinfo) - __builtin_thread_pointer();
+}
+
+*/
+ cfi_startproc
+ eabi_fnstart
+ .align 2
+_dl_tlsdesc_dynamic:
+ /* Our calling convention is to clobber r0, r1 and the processor
+ flags. All others that are modified must be saved */
+ eabi_save ({r2,r3,r4,lr})
+ push {r2,r3,r4,lr}
+ cfi_adjust_cfa_offset (16)
+ cfi_rel_offset (r2,0)
+ cfi_rel_offset (r3,4)
+ cfi_rel_offset (r4,8)
+ cfi_rel_offset (lr,12)
+ sfi_breg r0, \
+ ldr r1, [\B] /* td */
+ GET_TLS (lr)
+ mov r4, r0 /* r4 = tp */
+ sfi_breg r0, \
+ ldr r0, [\B]
+ sfi_breg r1, \
+ ldr r2, [\B, #8] /* gen_count */
+ sfi_breg r0, \
+ ldr r3, [\B]
+ cmp r2, r3
+ bhi 1f
+ sfi_breg r1, \
+ ldr r3, [\B]
+#ifndef ARM_NO_INDEX_REGISTER
+ ldr r2, [r0, r3, lsl #3]
+#else
+ add lr, r0, r3, lsl #3
+ sfi_breg lr, \
+ ldr r2, [\B]
+#endif
+ cmn r2, #1
+ ittt ne
+ sfi_breg r1, \
+ ldrne r3, [r1, #4]
+ addne r3, r2, r3
+ rsbne r0, r4, r3
+ bne 2f
+1: mov r0, r1
+ bl __tls_get_addr
+ rsb r0, r4, r0
+2:
+#if ((defined (__ARM_ARCH_4T__) && defined (__THUMB_INTERWORK__)) \
+ || defined (ARM_ALWAYS_BX))
+ pop {r2,r3,r4, lr}
+ cfi_adjust_cfa_offset (-16)
+ cfi_restore (lr)
+ cfi_restore (r4)
+ cfi_restore (r3)
+ cfi_restore (r2)
+ bx lr
+#else
+ pop {r2,r3,r4, pc}
+#endif
+ eabi_fnend
+ cfi_endproc
+ .size _dl_tlsdesc_dynamic, .-_dl_tlsdesc_dynamic
+#endif /* SHARED */
+
+/* lazy resolved for tls descriptors. */
+ .hidden _dl_tlsdesc_lazy_resolver
+ .global _dl_tlsdesc_lazy_resolver
+ .type _dl_tlsdesc_lazy_resolver,#function
+ cfi_startproc
+ eabi_fnstart
+ .align 2
+_dl_tlsdesc_lazy_resolver:
+ /* r0 points at the tlsdesc,
+ r1 points at the GOT
+ r2 was pushed by the trampoline and used as a temp,
+ we need to pop it here.
+ We push the remaining call-clobbered registers here, and also
+ R1 -- to keep the stack correctly aligned. */
+ /* Tell the unwinder that r2 has already been pushed. */
+ eabi_save ({r2})
+ cfi_adjust_cfa_offset (4)
+ cfi_rel_offset (r2, 0)
+ eabi_save ({r0,r1,r3,ip,lr})
+ push {r0, r1, r3, ip, lr}
+ cfi_adjust_cfa_offset (20)
+ cfi_rel_offset (r0, 0)
+ cfi_rel_offset (r1, 4)
+ cfi_rel_offset (r3, 8)
+ cfi_rel_offset (ip, 12)
+ cfi_rel_offset (lr, 16)
+ bl _dl_tlsdesc_lazy_resolver_fixup
+ pop {r0, r1, r3, ip, lr}
+ cfi_adjust_cfa_offset (-20)
+ cfi_restore (lr)
+ cfi_restore (ip)
+ cfi_restore (r3)
+ cfi_restore (r1)
+ cfi_restore (r0)
+ pop {r2}
+ cfi_adjust_cfa_offset (-4)
+ cfi_restore (r2)
+ sfi_breg r0, \
+ ldr r1, [\B, #4]
+ BX (r1)
+ eabi_fnend
+ cfi_endproc
+ .size _dl_tlsdesc_lazy_resolver, .-_dl_tlsdesc_lazy_resolver
+
+/* Holder for lazy tls descriptors being resolve in another thread.
+ Same ABI as the lazy resolver itself. */
+ .hidden _dl_tlsdesc_resolve_hold
+ .global _dl_tlsdesc_resolve_hold
+ .type _dl_tlsdesc_resolve_hold,#function
+ cfi_startproc
+ eabi_fnstart
+ .align 2
+_dl_tlsdesc_resolve_hold:
+ /* Tell the unwinder that r2 has already been pushed. */
+ eabi_save ({r2})
+ cfi_adjust_cfa_offset (4)
+ cfi_rel_offset (r2, 0)
+ eabi_save ({r0,r1,r3,ip,lr})
+ push {r0, r1, r3, ip, lr}
+ cfi_adjust_cfa_offset (20)
+ cfi_rel_offset (r0, 0)
+ cfi_rel_offset (r1, 4)
+ cfi_rel_offset (r3, 8)
+ cfi_rel_offset (ip, 12)
+ cfi_rel_offset (lr, 16)
+ adr r2, _dl_tlsdesc_resolve_hold
+ bl _dl_tlsdesc_resolve_hold_fixup
+ pop {r0, r1, r3, ip, lr}
+ cfi_adjust_cfa_offset (-20)
+ cfi_restore (lr)
+ cfi_restore (ip)
+ cfi_restore (r3)
+ cfi_restore (r1)
+ cfi_restore (r0)
+ pop {r2}
+ cfi_adjust_cfa_offset (-4)
+ cfi_restore (r2)
+ sfi_breg r0, \
+ ldr r1, [\B, #4]
+ BX (r1)
+ eabi_fnend
+ cfi_endproc
+ .size _dl_tlsdesc_resolve_hold, .-_dl_tlsdesc_resolve_hold