sysdeps/s390/tst-dl-runtime.c

   1 /* Test that lazy binding does not clobber r0.
   2    Copyright (C) 2018-2021 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 <assert.h>
  20 #include <dlfcn.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24
  25 #if defined (__s390x__)
  26 static const unsigned long magic_value = 0x0011223344556677UL;
  27 #else
  28 static const unsigned long magic_value = 0x00112233;
  29 #endif
  30
  31 unsigned long r0x2_trampoline (unsigned long);
  32
  33 /* Invoke r0x2, which doubles the value in r0.  If we get
  34    value * 2 back, this means nothing clobbers r0, particularly,
  35    _dl_runtime_resolve and _dl_runtime_profile.  */
  36 asm ("    .type r0x2_trampoline, @function\n"
  37      "r0x2_trampoline:\n"
  38 #if defined (__s390x__)
  39      "    lgr %r0,%r2\n"
  40      "    stg %r14,112(%r15)\n"
  41      "    aghi %r15,-160\n"
  42      "    brasl %r14,r0x2@plt\n"
  43      "    aghi %r15,160\n"
  44      "    lg %r14,112(%r15)\n"
  45      "    lgr %r2,%r0\n"
  46      "    br %r14\n"
  47 #elif defined (__zarch__)
  48      "    lr %r0,%r2\n"
  49      "    st %r14,56(%r15)\n"
  50      "    ahi %r15,-96\n"
  51      "    brasl %r14,r0x2@plt\n"
  52      "    ahi %r15,96\n"
  53      "    l %r14,56(%r15)\n"
  54      "    lr %r2,%r0\n"
  55      "    br %r14\n"
  56 #else
  57      "    lr %r0,%r2\n"
  58      "    st %r14,56(%r15)\n"
  59      "    ahi %r15,-96\n"
  60      "    balr %r14,0\n"
  61      "    l %r14,1f-.(%r14)\n"
  62      "    basr %r14,%r14\n"
  63      "    ahi %r15,96\n"
  64      "    l %r14,56(%r15)\n"
  65      "    lr %r2,%r0\n"
  66      "    br %r14\n"
  67      "1: .long r0x2\n"
  68 #endif
  69      );
  70
  71 static int
  72 do_test (void)
  73 {
  74   int i;
  75   unsigned long r0;
  76   const char *run;
  77
  78   for (i = 0; i < 2; i++)
  79     {
  80       run = (i == 0) ? "lazy" : "non-lazy";
  81       r0 = magic_value;
  82       printf ("-> %s r0 = 0x%lx\n", run, r0);
  83       r0 = r0x2_trampoline (r0);
  84       printf ("<- %s r0 * 2 = 0x%lx\n", run, r0);
  85       if (r0 != magic_value * 2)
  86         return EXIT_FAILURE;
  87     }
  88   return EXIT_SUCCESS;
  89 }
  90
  91 #include <support/test-driver.c>