mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 13:00:06 +00:00
7bd06985c0
The functions were previously written in C, but were not compiled with unwind information. The ENTRY/END macros includes .cfi_startproc and .cfi_endproc which adds unwind information. This caused the tests cleanup-8 and cleanup-10 in the GCC testsuite to fail. This patch adds a version of the ENTRY/END macros without the CFI instructions that can be used instead. sigaction registers a restorer address that is located two instructions before the stub function. This patch adds a two instruction padding to avoid that the unwinder accesses the unwind information from the function that the linker has placed right before it in memory. This fixes an issue with pthread_cancel that caused tst-mutex8-static (and other tests) to fail. Signed-off-by: Daniel Cederman <cederman@gaisler.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
92 lines
2.9 KiB
C
92 lines
2.9 KiB
C
/* Copyright (C) 2011-2024 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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#define _SYSDEPS_SYSDEP_H 1
|
|
#include <bits/hwcap.h>
|
|
|
|
#ifdef __ASSEMBLER__
|
|
|
|
#define SPARC_PIC_THUNK(reg) \
|
|
.ifndef __sparc_get_pc_thunk.reg; \
|
|
.section .text.__sparc_get_pc_thunk.reg,"axG",@progbits,__sparc_get_pc_thunk.reg,comdat; \
|
|
.align 32; \
|
|
.weak __sparc_get_pc_thunk.reg; \
|
|
.hidden __sparc_get_pc_thunk.reg; \
|
|
.type __sparc_get_pc_thunk.reg, #function; \
|
|
__sparc_get_pc_thunk.reg: \
|
|
jmp %o7 + 8; \
|
|
add %o7, %reg, %##reg; \
|
|
.previous; \
|
|
.endif;
|
|
|
|
/* The "-4" and "+4" offsets against _GLOBAL_OFFSET_TABLE_ are
|
|
critical since they represent the offset from the thunk call to the
|
|
instruction containing the _GLOBAL_OFFSET_TABLE_ reference.
|
|
Therefore these instructions cannot be moved around without
|
|
appropriate adjustments to those offsets.
|
|
|
|
Furthermore, these expressions are special in another regard. When
|
|
the assembler sees a reference to _GLOBAL_OFFSET_TABLE_ inside of
|
|
a %hi() or %lo(), it emits a PC-relative relocation. This causes
|
|
R_SPARC_HI22 to turn into R_SPARC_PC22, and R_SPARC_LO10 to turn into
|
|
R_SPARC_PC10, respectively.
|
|
|
|
Even when v9 we use a call sequence instead of using "rd %pc" because
|
|
RDPC is extremely expensive and incurs a full pipeline flush. */
|
|
|
|
#define SPARC_PIC_THUNK_CALL(reg) \
|
|
sethi %hi(_GLOBAL_OFFSET_TABLE_-4), %##reg; \
|
|
call __sparc_get_pc_thunk.reg; \
|
|
or %##reg, %lo(_GLOBAL_OFFSET_TABLE_+4), %##reg;
|
|
|
|
#define SETUP_PIC_REG(reg) \
|
|
SPARC_PIC_THUNK(reg) \
|
|
SPARC_PIC_THUNK_CALL(reg)
|
|
|
|
#define SETUP_PIC_REG_LEAF(reg, tmp) \
|
|
SPARC_PIC_THUNK(reg) \
|
|
mov %o7, %##tmp; \
|
|
SPARC_PIC_THUNK_CALL(reg); \
|
|
mov %##tmp, %o7;
|
|
|
|
#undef ENTRY
|
|
#define ENTRY(name) \
|
|
.align 4; \
|
|
.global C_SYMBOL_NAME(name); \
|
|
.type name, @function; \
|
|
C_LABEL(name) \
|
|
cfi_startproc;
|
|
|
|
#undef END
|
|
#define END(name) \
|
|
cfi_endproc; \
|
|
.size name, . - name
|
|
|
|
#define ENTRY_NOCFI(name) \
|
|
.align 4; \
|
|
.global C_SYMBOL_NAME(name); \
|
|
.type name, @function; \
|
|
C_LABEL(name)
|
|
|
|
#define END_NOCFI(name) \
|
|
.size name, . - name
|
|
|
|
#undef LOC
|
|
#define LOC(name) .L##name
|
|
|
|
#endif /* __ASSEMBLER__ */
|