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/* Copyright (C) 2011-2020 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
#undef LOC
#define LOC(name) .L##name
#endif /* __ASSEMBLER__ */
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