glibc/sysdeps/sparc/sysdep.h
Adam Conrad 105fa38156 Allow sys/auxv.h to be used from the testsuite on powerpc and sparc.
elf/tst-auxv.c includes misc/sys/auxv.h, which ends up not actually
being included due to the guard overlap, and getauxval becomes an
implicit declaration and implicit pointer conversion which means, at
best, the test isn't actually testing what it thinks it is and, at
worst, it'll crash and burn on platforms where implict pointer
conversion is a Very Bad Thing.

	* sysdeps/powerpc/bits/hwcap.h: Allow _SYSDEPS_SYSDEP_H guard as a
	synonym for _SYS_AUXV_H to allow direct inclusion.
	* sysdeps/sparc/bits/hwcap.h: Likewise.
	* sysdeps/powerpc/sysdep.h: Define _SYSDEPS_SYSDEP_H instead of
	_SYS_AUXV_H so we can include sysdep.h and sys/auxv.h together.
	* sysdeps/sparc/sysdep.h: Likewise.
2014-02-21 00:24:03 -07:00

83 lines
2.7 KiB
C

/* Copyright (C) 2011-2014 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/>. */
#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__ */