mirror of
git://gcc.gnu.org/git/gcc.git
synced 2024-12-21 14:59:58 +08:00
116 lines
3.4 KiB
C
116 lines
3.4 KiB
C
/*
|
|
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
|
|
*
|
|
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
|
|
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
|
|
*
|
|
* Permission is hereby granted to use or copy this program
|
|
* for any purpose, provided the above notices are retained on all copies.
|
|
* Permission to modify the code and to distribute modified code is granted,
|
|
* provided the above notices are retained, and a notice that the code was
|
|
* modified is included with the above copyright notice.
|
|
*/
|
|
/* Boehm, September 21, 1995 5:39 pm PDT */
|
|
|
|
/* Check whether setjmp actually saves registers in jmp_buf. */
|
|
/* If it doesn't, the generic mark_regs code won't work. */
|
|
/* Compilers vary as to whether they will put x in a */
|
|
/* (callee-save) register without -O. The code is */
|
|
/* contrived such that any decent compiler should put x in */
|
|
/* a callee-save register with -O. Thus it is is */
|
|
/* recommended that this be run optimized. (If the machine */
|
|
/* has no callee-save registers, then the generic code is */
|
|
/* safe, but this will not be noticed by this piece of */
|
|
/* code.) */
|
|
#include <stdio.h>
|
|
#include <setjmp.h>
|
|
#include <string.h>
|
|
#include "config.h"
|
|
|
|
#ifdef OS2
|
|
/* GETPAGESIZE() is set to getpagesize() by default, but that */
|
|
/* doesn't really exist, and the collector doesn't need it. */
|
|
#define INCL_DOSFILEMGR
|
|
#define INCL_DOSMISC
|
|
#define INCL_DOSERRORS
|
|
#include <os2.h>
|
|
|
|
int
|
|
getpagesize()
|
|
{
|
|
ULONG result[1];
|
|
|
|
if (DosQuerySysInfo(QSV_PAGE_SIZE, QSV_PAGE_SIZE,
|
|
(void *)result, sizeof(ULONG)) != NO_ERROR) {
|
|
fprintf(stderr, "DosQuerySysInfo failed\n");
|
|
result[0] = 4096;
|
|
}
|
|
return((int)(result[0]));
|
|
}
|
|
#endif
|
|
|
|
struct {char a_a; char * a_b;} a;
|
|
|
|
int * nested_sp()
|
|
{
|
|
int dummy;
|
|
|
|
return(&dummy);
|
|
}
|
|
|
|
main()
|
|
{
|
|
int dummy;
|
|
long ps = GETPAGESIZE();
|
|
jmp_buf b;
|
|
register int x = (int)strlen("a"); /* 1, slightly disguised */
|
|
static int y = 0;
|
|
|
|
printf("This appears to be a %s running %s\n", MACH_TYPE, OS_TYPE);
|
|
if (nested_sp() < &dummy) {
|
|
printf("Stack appears to grow down, which is the default.\n");
|
|
printf("A good guess for STACKBOTTOM on this machine is 0x%lx.\n",
|
|
((unsigned long)(&dummy) + ps) & ~(ps-1));
|
|
} else {
|
|
printf("Stack appears to grow up.\n");
|
|
printf("Define STACK_GROWS_UP in gc_private.h\n");
|
|
printf("A good guess for STACKBOTTOM on this machine is 0x%lx.\n",
|
|
((unsigned long)(&dummy) + ps) & ~(ps-1));
|
|
}
|
|
printf("Note that this may vary between machines of ostensibly\n");
|
|
printf("the same architecture (e.g. Sun 3/50s and 3/80s).\n");
|
|
printf("On many machines the value is not fixed.\n");
|
|
printf("A good guess for ALIGNMENT on this machine is %ld.\n",
|
|
(unsigned long)(&(a.a_b))-(unsigned long)(&a));
|
|
|
|
/* Encourage the compiler to keep x in a callee-save register */
|
|
x = 2*x-1;
|
|
printf("");
|
|
x = 2*x-1;
|
|
setjmp(b);
|
|
if (y == 1) {
|
|
if (x == 2) {
|
|
printf("Generic mark_regs code probably wont work\n");
|
|
# if defined(SPARC) || defined(RS6000) || defined(VAX) || defined(MIPS) || defined(M68K) || defined(I386) || defined(NS32K) || defined(RT)
|
|
printf("Assembly code supplied\n");
|
|
# else
|
|
printf("Need assembly code\n");
|
|
# endif
|
|
} else if (x == 1) {
|
|
printf("Generic mark_regs code may work\n");
|
|
} else {
|
|
printf("Very strange setjmp implementation\n");
|
|
}
|
|
}
|
|
y++;
|
|
x = 2;
|
|
if (y == 1) longjmp(b,1);
|
|
return(0);
|
|
}
|
|
|
|
int g(x)
|
|
int x;
|
|
{
|
|
return(x);
|
|
}
|