gdb/testsuite/gdb.base/restore.c

   1 /* This testcase is part of GDB, the GNU debugger.
   2
   3    Copyright 1998-2021 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 /* Test GDB's ability to restore saved registers from stack frames
  19    when using the `return' command.
  20    Jim Blandy <jimb@cygnus.com> --- December 1998 */
  21
  22 #include <stdio.h>
  23
  24 /* This is the Emacs Lisp expression I used to generate the functions
  25    in this file.  If people modify the functions manually, instead of
  26    changing this expression and re-running it, then evaluating this
  27    expression could wipe out their work, so you probably shouldn't
  28    re-run it.  But I leave it here for reference.
  29
  30    (defun callee (n) (format "callee%d" n))
  31    (defun caller (n) (format "caller%d" n))
  32    (defun local  (n) (format "l%d"  n))
  33    (defun local-sum (n)
  34      (if (zerop n) (insert "0")
  35        (let ((j 1))
  36          (while (<= j n)
  37            (insert (local j))
  38            (if (< j n) (insert "+"))
  39            (setq j (1+ j))))))
  40    (defun local-chain (n previous first-end)
  41      (let ((j 1))
  42        (while (<= j n)
  43          (insert "  register int " (local j)
  44                  " = increment (" previous  ");")
  45          (if first-end
  46            (progn
  47              (insert "  /" "* " first-end " prologue *" "/")
  48              (setq first-end nil)))
  49          (insert "\n")
  50          (setq previous (local j))
  51          (setq j (1+ j))))
  52      previous)
  53
  54    (save-excursion
  55      (let ((limit 5))
  56        (goto-char (point-max))
  57        (search-backward "generated code starts here")
  58        (forward-line 1)
  59        (let ((start (point)))
  60          (search-forward "generated code ends here")
  61          (forward-line 0)
  62          (delete-region start (point)))
  63
  64        ;; Generate callee functions.
  65        (let ((i 0))
  66          (while (<= i limit)
  67            (insert (format "/%s Returns n * %d + %d %s/\n"
  68                            "*" i (/ (+ i (* i i)) 2) "*"))
  69            (insert "int\n")
  70            (insert (callee i) " (int n)\n")
  71            (insert "{\n")
  72            (local-chain i "n" (callee i))
  73            (insert "  return ")
  74            (local-sum i)
  75            (insert ";\n")
  76            (insert "}\n\n")
  77            (setq i (1+ i))))
  78
  79        ;; Generate caller functions.
  80        (let ((i 1))
  81          (while (<= i limit)
  82            (insert "int\n")
  83            (insert (caller i) " (void)\n")
  84            (insert "{\n")
  85            (let ((last (local-chain i "0x7eeb" (caller i))))
  86              (insert "  register int n;\n")
  87              (let ((j 0))
  88                (while (<= j limit)
  89                  (insert "  n = " (callee j) " ("
  90                          (if (> j 0) "n + " "")
  91                          last ");\n")
  92                  (setq j (1+ j)))))
  93            (insert "  return n+")
  94            (local-sum i)
  95            (insert ";\n")
  96            (insert "}\n\n")
  97            (setq i (1+ i))))
  98
  99        ;; Generate driver function.
 100        (insert "void\n")
 101        (insert "driver (void)\n")
 102        (insert "{\n")
 103        (let ((i 1))
 104          (while (<= i limit)
 105            (insert "  printf (\"" (caller i) " () => %d\\n\", "
 106                    (caller i) " ());\n")
 107            (setq i (1+ i))))
 108        (insert "}\n\n")))
 109
 110          */
 111
 112 int
 113 increment (int n)
 114 {
 115   return n + 1;
 116 }
 117
 118 /* generated code starts here */
 119 /* Returns n * 0 + 0 */
 120 int
 121 callee0 (int n)
 122 {
 123   return 0;
 124 }
 125
 126 /* Returns n * 1 + 1 */
 127 int
 128 callee1 (int n)
 129 {
 130   register int l1 = increment (n);  /* callee1 prologue */
 131   return l1;
 132 }
 133
 134 /* Returns n * 2 + 3 */
 135 int
 136 callee2 (int n)
 137 {
 138   register int l1 = increment (n);  /* callee2 prologue */
 139   register int l2 = increment (l1);
 140   return l1+l2;
 141 }
 142
 143 /* Returns n * 3 + 6 */
 144 int
 145 callee3 (int n)
 146 {
 147   register int l1 = increment (n);  /* callee3 prologue */
 148   register int l2 = increment (l1);
 149   register int l3 = increment (l2);
 150   return l1+l2+l3;
 151 }
 152
 153 /* Returns n * 4 + 10 */
 154 int
 155 callee4 (int n)
 156 {
 157   register int l1 = increment (n);  /* callee4 prologue */
 158   register int l2 = increment (l1);
 159   register int l3 = increment (l2);
 160   register int l4 = increment (l3);
 161   return l1+l2+l3+l4;
 162 }
 163
 164 /* Returns n * 5 + 15 */
 165 int
 166 callee5 (int n)
 167 {
 168   register int l1 = increment (n);  /* callee5 prologue */
 169   register int l2 = increment (l1);
 170   register int l3 = increment (l2);
 171   register int l4 = increment (l3);
 172   register int l5 = increment (l4);
 173   return l1+l2+l3+l4+l5;
 174 }
 175
 176 int
 177 caller1 (void)
 178 {
 179   register int l1 = increment (0x7eeb);  /* caller1 prologue */
 180   register int n;
 181   n = callee0 (l1);
 182   n = callee1 (n + l1);
 183   n = callee2 (n + l1);
 184   n = callee3 (n + l1);
 185   n = callee4 (n + l1);
 186   n = callee5 (n + l1);
 187   return n+l1;
 188 }
 189
 190 int
 191 caller2 (void)
 192 {
 193   register int l1 = increment (0x7eeb);  /* caller2 prologue */
 194   register int l2 = increment (l1);
 195   register int n;
 196   n = callee0 (l2);
 197   n = callee1 (n + l2);
 198   n = callee2 (n + l2);
 199   n = callee3 (n + l2);
 200   n = callee4 (n + l2);
 201   n = callee5 (n + l2);
 202   return n+l1+l2;
 203 }
 204
 205 int
 206 caller3 (void)
 207 {
 208   register int l1 = increment (0x7eeb);  /* caller3 prologue */
 209   register int l2 = increment (l1);
 210   register int l3 = increment (l2);
 211   register int n;
 212   n = callee0 (l3);
 213   n = callee1 (n + l3);
 214   n = callee2 (n + l3);
 215   n = callee3 (n + l3);
 216   n = callee4 (n + l3);
 217   n = callee5 (n + l3);
 218   return n+l1+l2+l3;
 219 }
 220
 221 int
 222 caller4 (void)
 223 {
 224   register int l1 = increment (0x7eeb);  /* caller4 prologue */
 225   register int l2 = increment (l1);
 226   register int l3 = increment (l2);
 227   register int l4 = increment (l3);
 228   register int n;
 229   n = callee0 (l4);
 230   n = callee1 (n + l4);
 231   n = callee2 (n + l4);
 232   n = callee3 (n + l4);
 233   n = callee4 (n + l4);
 234   n = callee5 (n + l4);
 235   return n+l1+l2+l3+l4;
 236 }
 237
 238 int
 239 caller5 (void)
 240 {
 241   register int l1 = increment (0x7eeb);  /* caller5 prologue */
 242   register int l2 = increment (l1);
 243   register int l3 = increment (l2);
 244   register int l4 = increment (l3);
 245   register int l5 = increment (l4);
 246   register int n;
 247   n = callee0 (l5);
 248   n = callee1 (n + l5);
 249   n = callee2 (n + l5);
 250   n = callee3 (n + l5);
 251   n = callee4 (n + l5);
 252   n = callee5 (n + l5);
 253   return n+l1+l2+l3+l4+l5;
 254 }
 255
 256 void
 257 driver (void)
 258 {
 259   printf ("caller1 () => %d\n", caller1 ());
 260   printf ("caller2 () => %d\n", caller2 ());
 261   printf ("caller3 () => %d\n", caller3 ());
 262   printf ("caller4 () => %d\n", caller4 ());
 263   printf ("caller5 () => %d\n", caller5 ());
 264 }
 265
 266 /* generated code ends here */
 267
 268 int main ()
 269 {
 270   register int local;
 271   driver ();
 272   printf("exiting\n");
 273   return 0;
 274 }