1 /* Test if POWER vscr read by ucontext.
2    Copyright (C) 2018-2022 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
do_test(void)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>
86