1  /* Test if POWER vscr read by ucontext.
       2     Copyright (C) 2018-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <support/check.h>
      20  #include <sys/auxv.h>
      21  #include <ucontext.h>
      22  #include <stdlib.h>
      23  #include <stdio.h>
      24  #include <stdint.h>
      25  #include <altivec.h>
      26  
      27  #define SAT 0x1
      28  
      29  /* This test is supported only on POWER 5 or higher.  */
      30  #define PPC_CPU_SUPPORTED (PPC_FEATURE_POWER5 | PPC_FEATURE_POWER5_PLUS \
      31  			   | PPC_FEATURE_ARCH_2_05 | PPC_FEATURE_ARCH_2_06 \
      32  			   | PPC_FEATURE2_ARCH_2_07)
      33  static int
      34  do_test (void)
      35  {
      36  
      37    if (!(getauxval(AT_HWCAP2) & PPC_CPU_SUPPORTED))
      38      {
      39        if (!(getauxval(AT_HWCAP) & PPC_CPU_SUPPORTED))
      40        FAIL_UNSUPPORTED("This test is unsupported on POWER < 5\n");
      41      }
      42  
      43    uint32_t vscr[4] __attribute__ ((aligned (16)));
      44    uint32_t* vscr_ptr = vscr;
      45    uint32_t vscr_word;
      46    ucontext_t ucp;
      47    __vector unsigned int v0 = {0};
      48    __vector unsigned int v1 = {0};
      49  
      50    /* Set SAT bit in VSCR register.  */
      51    asm volatile (".machine push;\n"
      52  		".machine \"power5\";\n"
      53  		".machine altivec;\n"
      54  		"vspltisb %0,0;\n"
      55  		"vspltisb %1,-1;\n"
      56  		"vpkuwus %0,%0,%1;\n"
      57  		"mfvscr %0;\n"
      58  		"stvx %0,0,%2;\n"
      59  		".machine pop;"
      60  		: "=v" (v0), "=v" (v1)
      61  		: "r" (vscr_ptr)
      62  		: "memory");
      63  #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
      64    vscr_word = vscr[0];
      65  #else
      66    vscr_word = vscr[3];
      67  #endif
      68  
      69    if ((vscr_word & SAT) != SAT)
      70      {
      71        FAIL_EXIT1("FAIL: SAT bit is not set.\n");
      72      }
      73  
      74    if (getcontext (&ucp))
      75      {
      76        FAIL_EXIT1("FAIL: getcontext error\n");
      77      }
      78    if (ucp.uc_mcontext.v_regs->vscr.vscr_word != vscr_word)
      79      {
      80        FAIL_EXIT1("FAIL: ucontext vscr does not match with vscr\n");
      81      }
      82    return 0;
      83  }
      84  
      85  #include <support/test-driver.c>