glibc/sysdeps/s390/multiarch/ifunc-resolve.h
Stefan Liebler 51213e2b8d S390: Use new s390_libc_ifunc_expr macro in s390 8bit-generic.c.
This patch adds s390_libc_ifunc_expr macro which uses the __ifunc base macro
in include/libc-symbols.h and lets the user define a generic expression to
choose the correct ifunc variant.  Furthermore as the base macro is used,
the ifunc resolver functions are now also using inhibit_stack_protector.
S390 needs its own version due to the hwcap argument of the ifunc resolver.

This new macro is now used in iconv code in 8bit-generic.c instead of using
gcc attribute ifunc directly.

ChangeLog:

	* sysdeps/s390/multiarch/ifunc-resolve.h
	(s390_libc_ifunc_expr_init, s390_libc_ifunc_expr): New Define.
	* sysdeps/s390/multiarch/8bit-generic.c
	(__to_generic, __from_generic): Use s390_libc_ifunc_expr to
	define ifunc resolvers.
2017-04-21 15:30:00 +02:00

91 lines
3.7 KiB
C

/* IFUNC resolver function for CPU specific functions.
32/64 bit S/390 version.
Copyright (C) 2015-2017 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 <unistd.h>
#include <dl-procinfo.h>
#define S390_STFLE_BITS_Z10 34 /* General instructions extension */
#define S390_STFLE_BITS_Z196 45 /* Distinct operands, pop ... */
#define S390_IS_Z196(STFLE_BITS) \
((STFLE_BITS & (1ULL << (63 - S390_STFLE_BITS_Z196))) != 0)
#define S390_IS_Z10(STFLE_BITS) \
((STFLE_BITS & (1ULL << (63 - S390_STFLE_BITS_Z10))) != 0)
#define S390_STORE_STFLE(STFLE_BITS) \
/* We want just 1 double word to be returned. */ \
register unsigned long reg0 __asm__("0") = 0; \
\
__asm__ __volatile__(".machine push" "\n\t" \
".machine \"z9-109\"" "\n\t" \
".machinemode \"zarch_nohighgprs\"\n\t" \
"stfle %0" "\n\t" \
".machine pop" "\n" \
: "=QS" (STFLE_BITS), "+d" (reg0) \
: : "cc");
#define s390_libc_ifunc_init() \
unsigned long long stfle_bits = 0ULL; \
if (__glibc_likely((dl_hwcap & HWCAP_S390_STFLE) \
&& (dl_hwcap & HWCAP_S390_ZARCH) \
&& (dl_hwcap & HWCAP_S390_HIGH_GPRS))) \
{ \
S390_STORE_STFLE (stfle_bits); \
}
#define s390_libc_ifunc(TYPE_FUNC, RESOLVERFUNC, FUNC) \
/* Make the declarations of the optimized functions hidden in order
to prevent GOT slots being generated for them. */ \
extern __typeof (TYPE_FUNC) RESOLVERFUNC##_z196 attribute_hidden; \
extern __typeof (TYPE_FUNC) RESOLVERFUNC##_z10 attribute_hidden; \
extern __typeof (TYPE_FUNC) RESOLVERFUNC##_default attribute_hidden; \
__ifunc (TYPE_FUNC, FUNC, \
__glibc_likely (S390_IS_Z196 (stfle_bits)) \
? RESOLVERFUNC##_z196 \
: __glibc_likely (S390_IS_Z10 (stfle_bits)) \
? RESOLVERFUNC##_z10 \
: RESOLVERFUNC##_default, \
unsigned long int dl_hwcap, s390_libc_ifunc_init);
#define s390_vx_libc_ifunc(FUNC) \
s390_vx_libc_ifunc2_redirected(FUNC, FUNC, FUNC)
#define s390_vx_libc_ifunc_redirected(TYPE_FUNC, FUNC) \
s390_vx_libc_ifunc2_redirected(TYPE_FUNC, FUNC, FUNC)
#define s390_vx_libc_ifunc2(RESOLVERFUNC, FUNC) \
s390_vx_libc_ifunc2_redirected(FUNC, RESOLVERFUNC, FUNC)
#define s390_vx_libc_ifunc_init()
#define s390_vx_libc_ifunc2_redirected(TYPE_FUNC, RESOLVERFUNC, FUNC) \
/* Make the declarations of the optimized functions hidden in order
to prevent GOT slots being generated for them. */ \
extern __typeof (TYPE_FUNC) RESOLVERFUNC##_vx attribute_hidden; \
extern __typeof (TYPE_FUNC) RESOLVERFUNC##_c attribute_hidden; \
__ifunc (TYPE_FUNC, FUNC, \
(dl_hwcap & HWCAP_S390_VX) \
? RESOLVERFUNC##_vx \
: RESOLVERFUNC##_c, \
unsigned long int dl_hwcap, s390_vx_libc_ifunc_init);
#define s390_libc_ifunc_expr_init()
#define s390_libc_ifunc_expr(TYPE_FUNC, FUNC, EXPR) \
__ifunc (TYPE_FUNC, FUNC, EXPR, unsigned long int hwcap, \
s390_libc_ifunc_expr_init);