powerpc: Fix VSCR position in ucontext (bug 24088)

This patch fix VSCR position on ucontext. VSCR was read in the wrong
position on ucontext structure because it was ignoring the machine
endianess.

	[BZ #24088]
	* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h (vscr_t): Added
	ifdef to fix read of VSCR.
	* sysdeps/powerpc/powerpc64/Makefile [$subdir == stdlib]: Add
	tst-ucontext-ppc64-vscr.c to test list.
	* sysdeps/powerpc/powerpc64/tst-ucontext-ppc64-vscr.c: New test file.

Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
This commit is contained in:
Rogerio Alves 2018-11-05 10:18:38 -06:00 committed by Tulio Magno Quites Machado Filho
parent 5494af04ad
commit 0bc9bdf159
4 changed files with 102 additions and 0 deletions

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@ -1,3 +1,11 @@
2019-01-11 Rogerio A. Cardoso <rcardoso@linux.ibm.com>
* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h (vscr_t): Added
ifdef to fix read of VSCR.
* sysdeps/powerpc/powerpc64/Makefile [$subdir == stdlib]: Add
tst-ucontext-ppc64-vscr.c to test list.
* sysdeps/powerpc/powerpc64/tst-ucontext-ppc64-vscr.c: New test file.
2019-01-10 Andreas K. Hüttel <dilfridge@gentoo.org>
* resolv/tst-resolv-ai_idn-common.c (response): Avoid switch

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@ -59,3 +59,8 @@ $(objpfx)tst-setjmp-bug21895-static.out: $(objpfx)setjmp-bug21895.so
tst-setjmp-bug21895-static-ENV = \
LD_LIBRARY_PATH=$(objpfx):$(common-objpfx):$(common-objpfx)setjmp:$(common-objpfx)elf
endif
ifeq ($(subdir),stdlib)
CFLAGS-tst-ucontext-ppc64-vscr.c += -maltivec
tests += tst-ucontext-ppc64-vscr
endif

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@ -0,0 +1,84 @@
/* Test if POWER vscr read by ucontext.
Copyright (C) 2018 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 <support/check.h>
#include <sys/auxv.h>
#include <ucontext.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <altivec.h>
#define SAT 0x1
/* This test is supported only on POWER 5 or higher. */
#define PPC_CPU_SUPPORTED (PPC_FEATURE_POWER5 | PPC_FEATURE_POWER5_PLUS | \
PPC_FEATURE_ARCH_2_05 | PPC_FEATURE_ARCH_2_06 | \
PPC_FEATURE2_ARCH_2_07)
static int
do_test (void)
{
if (!(getauxval(AT_HWCAP2) & PPC_CPU_SUPPORTED))
{
if (!(getauxval(AT_HWCAP) & PPC_CPU_SUPPORTED))
FAIL_UNSUPPORTED("This test is unsupported on POWER < 5\n");
}
uint32_t vscr[4] __attribute__ ((aligned (16)));
uint32_t* vscr_ptr = vscr;
uint32_t vscr_word;
ucontext_t ucp;
__vector __int128_t v0 = {0};
__vector __int128_t v1 = {0};
/* Set SAT bit in VSCR register. */
asm volatile (".machine push;\n"
".machine \"power5\";\n"
"vspltisb %0,0;\n"
"vspltisb %1,-1;\n"
"vpkuwus %0,%0,%1;\n"
"mfvscr %0;\n"
"stvx %0,0,%2;\n"
".machine pop;"
: "=v" (v0), "=v" (v1)
: "r" (vscr_ptr)
: "memory");
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
vscr_word = vscr[0];
#else
vscr_word = vscr[3];
#endif
if ((vscr_word & SAT) != SAT)
{
FAIL_EXIT1("FAIL: SAT bit is not set.\n");
}
if (getcontext (&ucp))
{
FAIL_EXIT1("FAIL: getcontext error\n");
}
if (ucp.uc_mcontext.v_regs->vscr.vscr_word != vscr_word)
{
FAIL_EXIT1("FAIL: ucontext vscr does not match with vscr\n");
}
return 0;
}
#include <support/test-driver.c>

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@ -98,8 +98,13 @@ typedef double fpregset_t[__NFPREG];
a whole quadword speedup save/restore. */
typedef struct _libc_vscr
{
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
unsigned int __pad[3];
unsigned int __ctx(vscr_word);
#else
unsigned int __ctx(vscr_word);
unsigned int __pad[3];
#endif
} vscr_t;
/* Container for Altivec/VMX registers and status.