gdb/testsuite/gdb.arch/amd64-eval.cc

   1 /* This testcase is part of GDB, the GNU debugger.
   2
   3    Copyright 2019-2021 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include <cstdint>
  19 #include <cstdio>
  20 #include <cstdlib>
  21 #include <cassert>
  22
  23 /* A simple structure with a single integer field. Should be returned in
  24    a register.  */
  25 struct SimpleBase
  26 {
  27   SimpleBase (int32_t x) : x (x) {}
  28
  29   int32_t x;
  30 };
  31
  32 /* A simple structure derived from the simple base. Should be returned in
  33    a register.  */
  34 struct SimpleDerived : public SimpleBase
  35 {
  36   SimpleDerived (int32_t x) : SimpleBase (x) {}
  37 };
  38
  39 /* A structure derived from the simple base with a non-trivial destructor.
  40    Should be returned on the stack.  */
  41 struct NonTrivialDestructorDerived : public SimpleBase
  42 {
  43   NonTrivialDestructorDerived (int32_t x) : SimpleBase (x) {}
  44   ~NonTrivialDestructorDerived() { x = 1; }
  45 };
  46
  47 /* A structure with unaligned fields. Should be returned on the stack.  */
  48 struct UnalignedFields
  49 {
  50   UnalignedFields (int32_t x, double y) : x (x), y (y) {}
  51
  52   int32_t x;
  53   double y;
  54 } __attribute__((packed));
  55
  56 /* A structure with unaligned fields in its base class. Should be
  57    returned on the stack.  */
  58 struct UnalignedFieldsInBase : public UnalignedFields
  59 {
  60   UnalignedFieldsInBase (int32_t x, double y, int32_t x2)
  61   : UnalignedFields (x, y), x2 (x2) {}
  62
  63   int32_t x2;
  64 };
  65
  66 struct Bitfields
  67 {
  68   Bitfields(unsigned int x, unsigned int y)
  69     : fld(x), fld2(y)
  70   {}
  71
  72   unsigned fld : 7;
  73   unsigned fld2 : 7;
  74 };
  75
  76 class Foo
  77 {
  78 public:
  79   SimpleBase
  80   return_simple_base (int32_t x)
  81   {
  82     assert (this->tag == EXPECTED_TAG);
  83     return SimpleBase (x);
  84   }
  85
  86   SimpleDerived
  87   return_simple_derived (int32_t x)
  88   {
  89     assert (this->tag == EXPECTED_TAG);
  90     return SimpleDerived (x);
  91   }
  92
  93   NonTrivialDestructorDerived
  94   return_non_trivial_destructor (int32_t x)
  95   {
  96     assert (this->tag == EXPECTED_TAG);
  97     return NonTrivialDestructorDerived (x);
  98   }
  99
 100   UnalignedFields
 101   return_unaligned (int32_t x, double y)
 102   {
 103     assert (this->tag == EXPECTED_TAG);
 104     return UnalignedFields (x, y);
 105   }
 106
 107   UnalignedFieldsInBase
 108   return_unaligned_in_base (int32_t x, double y, int32_t x2)
 109   {
 110     assert (this->tag == EXPECTED_TAG);
 111     return UnalignedFieldsInBase (x, y, x2);
 112   }
 113
 114   Bitfields
 115   return_bitfields (unsigned int x, unsigned int y)
 116   {
 117     assert (this->tag == EXPECTED_TAG);
 118     return Bitfields(x, y);
 119   }
 120
 121 private:
 122   /* Use a tag to detect if the "this" value is correct.  */
 123   static const int EXPECTED_TAG = 0xF00F00F0;
 124   int tag = EXPECTED_TAG;
 125 };
 126
 127 int
 128 main (int argc, char *argv[])
 129 {
 130   Foo foo;
 131   foo.return_simple_base(1);
 132   foo.return_simple_derived(2);
 133   foo.return_non_trivial_destructor(3);
 134   foo.return_unaligned(4, 5);
 135   foo.return_unaligned_in_base(6, 7, 8);
 136   foo.return_bitfields(23, 74);
 137   return 0;  // break-here
 138 }