From f7d3468236f17f0d1c1ca5acf3865bc89ac27125 Mon Sep 17 00:00:00 2001 From: Rogerio Alves Date: Mon, 5 Nov 2018 10:18:38 -0600 Subject: [PATCH v3] powerpc: Fix VSCR position in ucontext. This patch fix VSCR position on ucontext. VSCR was read in the wrong position on ucontext structure because it was ignoring the machine endianess. 2018-11-05 Rogerio A. Cardoso * sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h (struct _libc_vscr, vscr_t): Added ifdef to fix read of VSCR. * sysdeps/powerpc/powerpc64/Makefile: Add tst-ucontext-ppc64-vscr.c to test list. * sysdeps/powerpc/powerpc64/tst-ucontext-ppc64-vscr.c: New test file. --- Patch v3: fixed as per Florian and Gabriel review. Using getauxval to get if (runtime) the test is supported instead using ifdef. Changed vpkudus por vpkuwus since it's supported by POWER 5 or higher. Patch v2: fixed as per Gabriel and Segher review. Fix formating and changelog Change the assembly inline to a better version. Changed ifdef to POWER8. sysdeps/powerpc/powerpc64/Makefile | 5 ++ .../powerpc/powerpc64/tst-ucontext-ppc64-vscr.c | 82 ++++++++++++++++++++++ sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h | 5 ++ 3 files changed, 92 insertions(+) create mode 100644 sysdeps/powerpc/powerpc64/tst-ucontext-ppc64-vscr.c diff --git a/sysdeps/powerpc/powerpc64/Makefile b/sysdeps/powerpc/powerpc64/Makefile index a0bd0c9..6e88df1 100644 --- a/sysdeps/powerpc/powerpc64/Makefile +++ b/sysdeps/powerpc/powerpc64/Makefile @@ -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 diff --git a/sysdeps/powerpc/powerpc64/tst-ucontext-ppc64-vscr.c b/sysdeps/powerpc/powerpc64/tst-ucontext-ppc64-vscr.c new file mode 100644 index 0000000..be99108 --- /dev/null +++ b/sysdeps/powerpc/powerpc64/tst-ucontext-ppc64-vscr.c @@ -0,0 +1,82 @@ +/* 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 + . */ + +#include +#include +#include +#include +#include +#include +#include + +#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 ("vspltisb %0,0\n" + "vspltisb %1,-1\n" + "vpkuwus %0,%0,%1\n" + "mfvscr %0\n" + "stvx %0,0,%2" + : "=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 diff --git a/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h b/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h index 1bb6e4c..49a92c5 100644 --- a/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h +++ b/sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h @@ -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. -- 2.7.4