1 files changed, 115 insertions, 0 deletions
diff --git a/boehm-gc/setjmp_t.c b/boehm-gc/setjmp_t.c
new file mode 100644
index 00000000000..9ed92138b6c
--- /dev/null
+++ b/boehm-gc/setjmp_t.c
@@ -0,0 +1,115 @@
+/*
+ * 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);
+}