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/* This testcase is part of GDB, the GNU debugger.
Copyright 1998-2021 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Test GDB's ability to restore saved registers from stack frames
when using the `return' command.
Jim Blandy <jimb@cygnus.com> --- December 1998 */
#include <stdio.h>
/* This is the Emacs Lisp expression I used to generate the functions
in this file. If people modify the functions manually, instead of
changing this expression and re-running it, then evaluating this
expression could wipe out their work, so you probably shouldn't
re-run it. But I leave it here for reference.
(defun callee (n) (format "callee%d" n))
(defun caller (n) (format "caller%d" n))
(defun local (n) (format "l%d" n))
(defun local-sum (n)
(if (zerop n) (insert "0")
(let ((j 1))
(while (<= j n)
(insert (local j))
(if (< j n) (insert "+"))
(setq j (1+ j))))))
(defun local-chain (n previous first-end)
(let ((j 1))
(while (<= j n)
(insert " register int " (local j)
" = increment (" previous ");")
(if first-end
(progn
(insert " /" "* " first-end " prologue *" "/")
(setq first-end nil)))
(insert "\n")
(setq previous (local j))
(setq j (1+ j))))
previous)
(save-excursion
(let ((limit 5))
(goto-char (point-max))
(search-backward "generated code starts here")
(forward-line 1)
(let ((start (point)))
(search-forward "generated code ends here")
(forward-line 0)
(delete-region start (point)))
;; Generate callee functions.
(let ((i 0))
(while (<= i limit)
(insert (format "/%s Returns n * %d + %d %s/\n"
"*" i (/ (+ i (* i i)) 2) "*"))
(insert "int\n")
(insert (callee i) " (int n)\n")
(insert "{\n")
(local-chain i "n" (callee i))
(insert " return ")
(local-sum i)
(insert ";\n")
(insert "}\n\n")
(setq i (1+ i))))
;; Generate caller functions.
(let ((i 1))
(while (<= i limit)
(insert "int\n")
(insert (caller i) " (void)\n")
(insert "{\n")
(let ((last (local-chain i "0x7eeb" (caller i))))
(insert " register int n;\n")
(let ((j 0))
(while (<= j limit)
(insert " n = " (callee j) " ("
(if (> j 0) "n + " "")
last ");\n")
(setq j (1+ j)))))
(insert " return n+")
(local-sum i)
(insert ";\n")
(insert "}\n\n")
(setq i (1+ i))))
;; Generate driver function.
(insert "void\n")
(insert "driver (void)\n")
(insert "{\n")
(let ((i 1))
(while (<= i limit)
(insert " printf (\"" (caller i) " () => %d\\n\", "
(caller i) " ());\n")
(setq i (1+ i))))
(insert "}\n\n")))
*/
int
increment (int n)
{
return n + 1;
}
/* generated code starts here */
/* Returns n * 0 + 0 */
int
callee0 (int n)
{
return 0;
}
/* Returns n * 1 + 1 */
int
callee1 (int n)
{
register int l1 = increment (n); /* callee1 prologue */
return l1;
}
/* Returns n * 2 + 3 */
int
callee2 (int n)
{
register int l1 = increment (n); /* callee2 prologue */
register int l2 = increment (l1);
return l1+l2;
}
/* Returns n * 3 + 6 */
int
callee3 (int n)
{
register int l1 = increment (n); /* callee3 prologue */
register int l2 = increment (l1);
register int l3 = increment (l2);
return l1+l2+l3;
}
/* Returns n * 4 + 10 */
int
callee4 (int n)
{
register int l1 = increment (n); /* callee4 prologue */
register int l2 = increment (l1);
register int l3 = increment (l2);
register int l4 = increment (l3);
return l1+l2+l3+l4;
}
/* Returns n * 5 + 15 */
int
callee5 (int n)
{
register int l1 = increment (n); /* callee5 prologue */
register int l2 = increment (l1);
register int l3 = increment (l2);
register int l4 = increment (l3);
register int l5 = increment (l4);
return l1+l2+l3+l4+l5;
}
int
caller1 (void)
{
register int l1 = increment (0x7eeb); /* caller1 prologue */
register int n;
n = callee0 (l1);
n = callee1 (n + l1);
n = callee2 (n + l1);
n = callee3 (n + l1);
n = callee4 (n + l1);
n = callee5 (n + l1);
return n+l1;
}
int
caller2 (void)
{
register int l1 = increment (0x7eeb); /* caller2 prologue */
register int l2 = increment (l1);
register int n;
n = callee0 (l2);
n = callee1 (n + l2);
n = callee2 (n + l2);
n = callee3 (n + l2);
n = callee4 (n + l2);
n = callee5 (n + l2);
return n+l1+l2;
}
int
caller3 (void)
{
register int l1 = increment (0x7eeb); /* caller3 prologue */
register int l2 = increment (l1);
register int l3 = increment (l2);
register int n;
n = callee0 (l3);
n = callee1 (n + l3);
n = callee2 (n + l3);
n = callee3 (n + l3);
n = callee4 (n + l3);
n = callee5 (n + l3);
return n+l1+l2+l3;
}
int
caller4 (void)
{
register int l1 = increment (0x7eeb); /* caller4 prologue */
register int l2 = increment (l1);
register int l3 = increment (l2);
register int l4 = increment (l3);
register int n;
n = callee0 (l4);
n = callee1 (n + l4);
n = callee2 (n + l4);
n = callee3 (n + l4);
n = callee4 (n + l4);
n = callee5 (n + l4);
return n+l1+l2+l3+l4;
}
int
caller5 (void)
{
register int l1 = increment (0x7eeb); /* caller5 prologue */
register int l2 = increment (l1);
register int l3 = increment (l2);
register int l4 = increment (l3);
register int l5 = increment (l4);
register int n;
n = callee0 (l5);
n = callee1 (n + l5);
n = callee2 (n + l5);
n = callee3 (n + l5);
n = callee4 (n + l5);
n = callee5 (n + l5);
return n+l1+l2+l3+l4+l5;
}
void
driver (void)
{
printf ("caller1 () => %d\n", caller1 ());
printf ("caller2 () => %d\n", caller2 ());
printf ("caller3 () => %d\n", caller3 ());
printf ("caller4 () => %d\n", caller4 ());
printf ("caller5 () => %d\n", caller5 ());
}
/* generated code ends here */
int main ()
{
register int local;
driver ();
printf("exiting\n");
return 0;
}
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