boehm-gc/mach_dep.c - gcc - Git at Google

 /*
  * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
  * 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, November 17, 1995 12:13 pm PST */
 # include "private/gc_priv.h"
 # include <stdio.h>
 # include <setjmp.h>
 # if defined(OS2) || defined(CX_UX)
 #   define _setjmp(b) setjmp(b)
 #   define _longjmp(b,v) longjmp(b,v)
 # endif
 # ifdef AMIGA
 #   ifndef __GNUC__
 #     include <dos.h>
 #   else
 #     include <machine/reg.h>
 #   endif
 # endif

 #if defined(RS6000) || defined(POWERPC)
 # include <ucontext.h>
 #endif

 #if defined(__MWERKS__) && !defined(POWERPC)

 asm static void PushMacRegisters()
 {
     sub.w   #4,sp                   // reserve space for one parameter.
     move.l  a2,(sp)
     jsr		GC_push_one
     move.l  a3,(sp)
     jsr		GC_push_one
     move.l  a4,(sp)
     jsr		GC_push_one
 #   if !__option(a6frames)
 	// <pcb> perhaps a6 should be pushed if stack frames are not being used.
   	move.l	a6,(sp)
   	jsr		GC_push_one
 #   endif
 	// skip a5 (globals), a6 (frame pointer), and a7 (stack pointer)
     move.l  d2,(sp)
     jsr		GC_push_one
     move.l  d3,(sp)
     jsr		GC_push_one
     move.l  d4,(sp)
     jsr		GC_push_one
     move.l  d5,(sp)
     jsr		GC_push_one
     move.l  d6,(sp)
     jsr		GC_push_one
     move.l  d7,(sp)
     jsr		GC_push_one
     add.w   #4,sp                   // fix stack.
     rts
 }

 #endif /* __MWERKS__ */

 # if defined(SPARC) || defined(IA64)
     /* Value returned from register flushing routine; either sp (SPARC) */
     /* or ar.bsp (IA64)							*/
     word GC_save_regs_ret_val;
 # endif

 /* Routine to mark from registers that are preserved by the C compiler. */
 /* This must be ported to every new architecture.  There is a generic   */
 /* version at the end, that is likely, but not guaranteed to work       */
 /* on your architecture.  Run the test_setjmp program to see whether    */
 /* there is any chance it will work.                                    */

 #if !defined(USE_GENERIC_PUSH_REGS) && !defined(USE_ASM_PUSH_REGS)
 #undef HAVE_PUSH_REGS
 void GC_push_regs()
 {
 #       ifdef RT
 	  register long TMP_SP; /* must be bound to r11 */
 #       endif

 #       ifdef VAX
 	  /* VAX - generic code below does not work under 4.2 */
 	  /* r1 through r5 are caller save, and therefore     */
 	  /* on the stack or dead.                            */
 	  asm("pushl r11");     asm("calls $1,_GC_push_one");
 	  asm("pushl r10"); 	asm("calls $1,_GC_push_one");
 	  asm("pushl r9");	asm("calls $1,_GC_push_one");
 	  asm("pushl r8");	asm("calls $1,_GC_push_one");
 	  asm("pushl r7");	asm("calls $1,_GC_push_one");
 	  asm("pushl r6");	asm("calls $1,_GC_push_one");
 #	  define HAVE_PUSH_REGS
 #       endif
 #       if defined(M68K) && (defined(SUNOS4) || defined(NEXT))
 	/*  M68K SUNOS - could be replaced by generic code */
 	  /* a0, a1 and d1 are caller save          */
 	  /*  and therefore are on stack or dead.   */

 	  asm("subqw #0x4,sp");		/* allocate word on top of stack */

 	  asm("movl a2,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl a3,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl a4,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl a5,sp@");	asm("jbsr _GC_push_one");
 	  /* Skip frame pointer and stack pointer */
 	  asm("movl d1,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl d2,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl d3,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl d4,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl d5,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl d6,sp@");	asm("jbsr _GC_push_one");
 	  asm("movl d7,sp@");	asm("jbsr _GC_push_one");

 	  asm("addqw #0x4,sp");		/* put stack back where it was	*/
 #	  define HAVE_PUSH_REGS
 #       endif

 #       if defined(M68K) && defined(HP)
 	/*  M68K HP - could be replaced by generic code */
 	  /* a0, a1 and d1 are caller save.  */

 	  asm("subq.w &0x4,%sp");	/* allocate word on top of stack */

 	  asm("mov.l %a2,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %a3,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %a4,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %a5,(%sp)"); asm("jsr _GC_push_one");
 	  /* Skip frame pointer and stack pointer */
 	  asm("mov.l %d1,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d2,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d3,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d4,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d5,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d6,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d7,(%sp)"); asm("jsr _GC_push_one");

 	  asm("addq.w &0x4,%sp");	/* put stack back where it was	*/
 #	  define HAVE_PUSH_REGS
 #       endif /* M68K HP */

 #	if defined(M68K) && defined(AMIGA)
  	 /*  AMIGA - could be replaced by generic code 			*/
  	 /* a0, a1, d0 and d1 are caller save */

 #        ifdef __GNUC__
 	  asm("subq.w &0x4,%sp");	/* allocate word on top of stack */

 	  asm("mov.l %a2,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %a3,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %a4,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %a5,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %a6,(%sp)"); asm("jsr _GC_push_one");
 	  /* Skip frame pointer and stack pointer */
 	  asm("mov.l %d2,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d3,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d4,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d5,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d6,(%sp)"); asm("jsr _GC_push_one");
 	  asm("mov.l %d7,(%sp)"); asm("jsr _GC_push_one");

 	  asm("addq.w &0x4,%sp");	/* put stack back where it was	*/
 #	  define HAVE_PUSH_REGS
 #        else /* !__GNUC__ */
 	  GC_push_one(getreg(REG_A2));
 	  GC_push_one(getreg(REG_A3));
 #         ifndef __SASC
 	      /* Can probably be changed to #if 0 -Kjetil M. (a4=globals)*/
 	    GC_push_one(getreg(REG_A4));
 #	  endif
 	  GC_push_one(getreg(REG_A5));
 	  GC_push_one(getreg(REG_A6));
 	  /* Skip stack pointer */
 	  GC_push_one(getreg(REG_D2));
 	  GC_push_one(getreg(REG_D3));
 	  GC_push_one(getreg(REG_D4));
 	  GC_push_one(getreg(REG_D5));
 	  GC_push_one(getreg(REG_D6));
 	  GC_push_one(getreg(REG_D7));
 #	  define HAVE_PUSH_REGS
 #	 endif /* !__GNUC__ */
 #       endif /* AMIGA */

 #	if defined(M68K) && defined(MACOS)
 #	if defined(THINK_C)
 #         define PushMacReg(reg) \
               move.l  reg,(sp) \
               jsr             GC_push_one
 	  asm {
               sub.w   #4,sp                   ; reserve space for one parameter.
               PushMacReg(a2);
               PushMacReg(a3);
               PushMacReg(a4);
               ; skip a5 (globals), a6 (frame pointer), and a7 (stack pointer)
               PushMacReg(d2);
               PushMacReg(d3);
               PushMacReg(d4);
               PushMacReg(d5);
               PushMacReg(d6);
               PushMacReg(d7);
               add.w   #4,sp                   ; fix stack.
 	  }
 #	  define HAVE_PUSH_REGS
 #	  undef PushMacReg
 #	endif /* THINK_C */
 #	if defined(__MWERKS__)
 	  PushMacRegisters();
 #	  define HAVE_PUSH_REGS
 #	endif	/* __MWERKS__ */
 #   endif	/* MACOS */

 #       if defined(I386) &&!defined(OS2) &&!defined(SVR4) \
 	&& (defined(__MINGW32__) || !defined(MSWIN32)) \
 	&& !defined(SCO) && !defined(SCO_ELF) \
  	&& !(defined(LINUX) && defined(__ELF__)) \
 	&& !(defined(FREEBSD) && defined(__ELF__)) \
 	&& !(defined(NETBSD) && defined(__ELF__)) \
 	&& !(defined(OPENBSD) && defined(__ELF__)) \
 	&& !(defined(BEOS) && defined(__ELF__)) \
 	&& !defined(DOS4GW) && !defined(HURD)
 	/* I386 code, generic code does not appear to work */
 	/* It does appear to work under OS2, and asms dont */
 	/* This is used for some 38g UNIX variants and for CYGWIN32 */
 	  asm("pushl %eax");  asm("call _GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %ecx");  asm("call _GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %edx");  asm("call _GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %ebp");  asm("call _GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %esi");  asm("call _GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %edi");  asm("call _GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %ebx");  asm("call _GC_push_one"); asm("addl $4,%esp");
 #	  define HAVE_PUSH_REGS
 #       endif

 #	if ( defined(I386) && defined(LINUX) && defined(__ELF__) ) \
 	|| ( defined(I386) && defined(FREEBSD) && defined(__ELF__) ) \
 	|| ( defined(I386) && defined(NETBSD) && defined(__ELF__) ) \
 	|| ( defined(I386) && defined(OPENBSD) && defined(__ELF__) ) \
 	|| ( defined(I386) && defined(HURD) && defined(__ELF__) ) \
 	|| ( defined(I386) && defined(DGUX) )

 	/* This is modified for Linux with ELF (Note: _ELF_ only) */
 	/* This section handles FreeBSD with ELF. */
 	/* Eax is caller-save and dead here.  Other caller-save 	*/
 	/* registers could also be skipped.  We assume there are no	*/
 	/* pointers in MMX registers, etc.				*/
 	/* We combine instructions in a single asm to prevent gcc from 	*/
 	/* inserting code in the middle.				*/
 	  asm("pushl %ecx; call GC_push_one; addl $4,%esp");
 	  asm("pushl %edx; call GC_push_one; addl $4,%esp");
 	  asm("pushl %ebp; call GC_push_one; addl $4,%esp");
 	  asm("pushl %esi; call GC_push_one; addl $4,%esp");
 	  asm("pushl %edi; call GC_push_one; addl $4,%esp");
 	  asm("pushl %ebx; call GC_push_one; addl $4,%esp");
 #	  define HAVE_PUSH_REGS
 #	endif

 #	if ( defined(I386) && defined(BEOS) && defined(__ELF__) )
 	/* As far as I can understand from				*/
 	/* http://www.beunited.org/articles/jbq/nasm.shtml,		*/
 	/* only ebp, esi, edi and ebx are not scratch. How MMX 		*/
 	/* etc. registers should be treated, I have no idea. 		*/
 	  asm("pushl %ebp; call GC_push_one; addl $4,%esp");
 	  asm("pushl %esi; call GC_push_one; addl $4,%esp");
 	  asm("pushl %edi; call GC_push_one; addl $4,%esp");
 	  asm("pushl %ebx; call GC_push_one; addl $4,%esp");
 #	  define HAVE_PUSH_REGS
 #       endif

 #       if defined(I386) && defined(MSWIN32) && !defined(__MINGW32__) \
 	   && !defined(USE_GENERIC)
 	/* I386 code, Microsoft variant		*/
 	  __asm  push eax
 	  __asm  call GC_push_one
 	  __asm  add esp,4
 	  __asm  push ebx
 	  __asm  call GC_push_one
 	  __asm  add esp,4
 	  __asm  push ecx
 	  __asm  call GC_push_one
 	  __asm  add esp,4
 	  __asm  push edx
 	  __asm  call GC_push_one
 	  __asm  add esp,4
 	  __asm  push ebp
 	  __asm  call GC_push_one
 	  __asm  add esp,4
 	  __asm  push esi
 	  __asm  call GC_push_one
 	  __asm  add esp,4
 	  __asm  push edi
 	  __asm  call GC_push_one
 	  __asm  add esp,4
 #	  define HAVE_PUSH_REGS
 #       endif

 #       if defined(I386) && (defined(SVR4) || defined(SCO) || defined(SCO_ELF))
 	/* I386 code, SVR4 variant, generic code does not appear to work */
 	  asm("pushl %eax");  asm("call GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %ebx");  asm("call GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %ecx");  asm("call GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %edx");  asm("call GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %ebp");  asm("call GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %esi");  asm("call GC_push_one"); asm("addl $4,%esp");
 	  asm("pushl %edi");  asm("call GC_push_one"); asm("addl $4,%esp");
 #	  define HAVE_PUSH_REGS
 #       endif

 #       ifdef NS32K
 	  asm ("movd r3, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
 	  asm ("movd r4, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
 	  asm ("movd r5, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
 	  asm ("movd r6, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
 	  asm ("movd r7, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
 #	  define HAVE_PUSH_REGS
 #       endif

 #       if defined(SPARC)
 	  GC_save_regs_ret_val = GC_save_regs_in_stack();
 #	  define HAVE_PUSH_REGS
 #       endif

 #	ifdef RT
 	    GC_push_one(TMP_SP);    /* GC_push_one from r11 */

 	    asm("cas r11, r6, r0"); GC_push_one(TMP_SP);	/* r6 */
 	    asm("cas r11, r7, r0"); GC_push_one(TMP_SP);	/* through */
 	    asm("cas r11, r8, r0"); GC_push_one(TMP_SP);	/* r10 */
 	    asm("cas r11, r9, r0"); GC_push_one(TMP_SP);
 	    asm("cas r11, r10, r0"); GC_push_one(TMP_SP);

 	    asm("cas r11, r12, r0"); GC_push_one(TMP_SP); /* r12 */
 	    asm("cas r11, r13, r0"); GC_push_one(TMP_SP); /* through */
 	    asm("cas r11, r14, r0"); GC_push_one(TMP_SP); /* r15 */
 	    asm("cas r11, r15, r0"); GC_push_one(TMP_SP);
 #	    define HAVE_PUSH_REGS
 #       endif

 #       if defined(M68K) && defined(SYSV)
   	/*  Once again similar to SUN and HP, though setjmp appears to work.
   		--Parag
   	 */
 #        ifdef __GNUC__
   	  asm("subqw #0x4,%sp");	/* allocate word on top of stack */

   	  asm("movl %a2,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %a3,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %a4,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %a5,%sp@");	asm("jbsr GC_push_one");
   	  /* Skip frame pointer and stack pointer */
   	  asm("movl %d1,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %d2,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %d3,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %d4,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %d5,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %d6,%sp@");	asm("jbsr GC_push_one");
   	  asm("movl %d7,%sp@");	asm("jbsr GC_push_one");

   	  asm("addqw #0x4,%sp");	/* put stack back where it was	*/
 #	  define HAVE_PUSH_REGS
 #        else /* !__GNUC__*/
   	  asm("subq.w &0x4,%sp");	/* allocate word on top of stack */

   	  asm("mov.l %a2,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %a3,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %a4,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %a5,(%sp)"); asm("jsr GC_push_one");
   	  /* Skip frame pointer and stack pointer */
   	  asm("mov.l %d1,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %d2,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %d3,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %d4,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %d5,(%sp)"); asm("jsr GC_push_one");
    	  asm("mov.l %d6,(%sp)"); asm("jsr GC_push_one");
   	  asm("mov.l %d7,(%sp)"); asm("jsr GC_push_one");

   	  asm("addq.w &0x4,%sp");	/* put stack back where it was	*/
 #	  define HAVE_PUSH_REGS
 #        endif /* !__GNUC__ */
 #       endif /* M68K/SYSV */

 #     if defined(PJ)
 	{
 	    register int * sp asm ("optop");
 	    extern int *__libc_stack_end;

 	    GC_push_all_stack (sp, __libc_stack_end);
 #	    define HAVE_PUSH_REGS
 	    /* Isn't this redundant with the code to push the stack? */
         }
 #     endif

       /* other machines... */
 #       if !defined(HAVE_PUSH_REGS)
 	    --> We just generated an empty GC_push_regs, which
 	    --> is almost certainly broken.  Try defining
 	    --> USE_GENERIC_PUSH_REGS instead.
 #       endif
 }
 #endif /* !USE_GENERIC_PUSH_REGS && !USE_ASM_PUSH_REGS */

 void GC_with_callee_saves_pushed(fn, arg)
 void (*fn)();
 ptr_t arg;
 {
     word dummy;

 #   if defined(USE_GENERIC_PUSH_REGS)
 #     ifdef HAVE_BUILTIN_UNWIND_INIT
         /* This was suggested by Richard Henderson as the way to	*/
         /* force callee-save registers and register windows onto	*/
         /* the stack.						*/
         __builtin_unwind_init();
 #     else /* !HAVE_BUILTIN_UNWIND_INIT */
 #      if defined(RS6000) || defined(POWERPC)
 	/* FIXME: RS6000 means AIX.				*/
         /* This should probably be used in all Posix/non-gcc	*/
         /* settings.  We defer that change to minimize risk.	*/
         ucontext_t ctxt;
         getcontext(&ctxt);
 #      else
         /* Generic code                          */
         /* The idea is due to Parag Patel at HP. */
         /* We're not sure whether he would like  */
         /* to be he acknowledged for it or not.  */
         jmp_buf regs;
         register word * i = (word *) regs;
         register ptr_t lim = (ptr_t)(regs) + (sizeof regs);

         /* Setjmp doesn't always clear all of the buffer.		*/
         /* That tends to preserve garbage.  Clear it.   		*/
   	for (; (char *)i < lim; i++) {
   	    *i = 0;
   	}
 #       if defined(MSWIN32) || defined(MSWINCE) \
                   || defined(UTS4) || defined(LINUX) || defined(EWS4800)
   	  (void) setjmp(regs);
 #       else
             (void) _setjmp(regs);
   	  /* We don't want to mess with signals. According to	*/
   	  /* SUSV3, setjmp() may or may not save signal mask.	*/
   	  /* _setjmp won't, but is less portable.		*/
 #       endif
 #      endif /* !AIX ... */
 #     endif /* !HAVE_BUILTIN_UNWIND_INIT */
 #   else
 #     if defined(PTHREADS) && !defined(MSWIN32) /* !USE_GENERIC_PUSH_REGS */
         /* We may still need this to save thread contexts.	*/
         ucontext_t ctxt;
         getcontext(&ctxt);
 #     else  /* Shouldn't be needed */
         ABORT("Unexpected call to GC_with_callee_saves_pushed");
 #     endif
 #   endif
 #   if (defined(SPARC) && !defined(HAVE_BUILTIN_UNWIND_INIT)) \
 	|| defined(IA64)
       /* On a register window machine, we need to save register	*/
       /* contents on the stack for this to work.  The setjmp	*/
       /* is probably not needed on SPARC, since pointers are	*/
       /* only stored in windowed or scratch registers.  It is	*/
       /* needed on IA64, since some non-windowed registers are	*/
       /* preserved.						*/
       {
         GC_save_regs_ret_val = GC_save_regs_in_stack();
 	/* On IA64 gcc, could use __builtin_ia64_flushrs() and	*/
 	/* __builtin_ia64_flushrs().  The latter will be done	*/
 	/* implicitly by __builtin_unwind_init() for gcc3.0.1	*/
 	/* and later.						*/
       }
 #   endif
     fn(arg);
     /* Strongly discourage the compiler from treating the above	*/
     /* as a tail-call, since that would pop the register 	*/
     /* contents before we get a chance to look at them.		*/
     GC_noop1((word)(&dummy));
 }

 #if defined(USE_GENERIC_PUSH_REGS)
 void GC_generic_push_regs(cold_gc_frame)
 ptr_t cold_gc_frame;
 {
     GC_with_callee_saves_pushed(GC_push_current_stack, cold_gc_frame);
 }
 #endif /* USE_GENERIC_PUSH_REGS */

 /* On register window machines, we need a way to force registers into 	*/
 /* the stack.	Return sp.						*/
 # ifdef SPARC
     asm("	.seg 	\"text\"");
 #   if defined(SVR4) || defined(NETBSD) || defined(FREEBSD)
       asm("	.globl	GC_save_regs_in_stack");
       asm("GC_save_regs_in_stack:");
       asm("	.type GC_save_regs_in_stack,#function");
 #   else
       asm("	.globl	_GC_save_regs_in_stack");
       asm("_GC_save_regs_in_stack:");
 #   endif
 #   if defined(__arch64__) || defined(__sparcv9)
       asm("	save	%sp,-128,%sp");
       asm("	flushw");
       asm("	ret");
       asm("	restore %sp,2047+128,%o0");
 #   else
       asm("	ta	0x3   ! ST_FLUSH_WINDOWS");
       asm("	retl");
       asm("	mov	%sp,%o0");
 #   endif
 #   ifdef SVR4
       asm("	.GC_save_regs_in_stack_end:");
       asm("	.size GC_save_regs_in_stack,.GC_save_regs_in_stack_end-GC_save_regs_in_stack");
 #   endif
 #   ifdef LINT
 	word GC_save_regs_in_stack() { return(0 /* sp really */);}
 #   endif
 # endif

 /* On IA64, we also need to flush register windows.  But they end	*/
 /* up on the other side of the stack segment.				*/
 /* Returns the backing store pointer for the register stack.		*/
 /* We now implement this as a separate assembly file, since inline	*/
 /* assembly code here doesn't work with either the Intel or HP 		*/
 /* compilers.								*/
 # if 0
 #   ifdef LINUX
 	asm("        .text");
 	asm("        .psr abi64");
 	asm("        .psr lsb");
 	asm("        .lsb");
 	asm("");
 	asm("        .text");
 	asm("        .align 16");
 	asm("        .global GC_save_regs_in_stack");
 	asm("        .proc GC_save_regs_in_stack");
 	asm("GC_save_regs_in_stack:");
 	asm("        .body");
 	asm("        flushrs");
 	asm("        ;;");
 	asm("        mov r8=ar.bsp");
 	asm("        br.ret.sptk.few rp");
 	asm("        .endp GC_save_regs_in_stack");
 #   endif /* LINUX */
 #   if 0 /* Other alternatives that don't work on HP/UX */
 	word GC_save_regs_in_stack() {
 #	  if USE_BUILTINS
 	    __builtin_ia64_flushrs();
 	    return __builtin_ia64_bsp();
 #	  else
 #	    ifdef HPUX
 	      _asm("        flushrs");
 	      _asm("        ;;");
 	      _asm("        mov r8=ar.bsp");
 	      _asm("        br.ret.sptk.few rp");
 #	    else
 	      asm("        flushrs");
 	      asm("        ;;");
 	      asm("        mov r8=ar.bsp");
 	      asm("        br.ret.sptk.few rp");
 #	    endif
 #	  endif
 	}
 #   endif
 # endif

 /* GC_clear_stack_inner(arg, limit) clears stack area up to limit and	*/
 /* returns arg.  Stack clearing is crucial on SPARC, so we supply	*/
 /* an assembly version that's more careful.  Assumes limit is hotter	*/
 /* than sp, and limit is 8 byte aligned.				*/
 #if defined(ASM_CLEAR_CODE)
 #ifndef SPARC
 	--> fix it
 #endif
 # ifdef SUNOS4
     asm(".globl _GC_clear_stack_inner");
     asm("_GC_clear_stack_inner:");
 # else
     asm(".globl GC_clear_stack_inner");
     asm("GC_clear_stack_inner:");
     asm(".type GC_save_regs_in_stack,#function");
 # endif
 #if defined(__arch64__) || defined(__sparcv9)
   asm("mov %sp,%o2");		/* Save sp			*/
   asm("add %sp,2047-8,%o3");	/* p = sp+bias-8		*/
   asm("add %o1,-2047-192,%sp");	/* Move sp out of the way,	*/
   				/* so that traps still work.	*/
   				/* Includes some extra words	*/
   				/* so we can be sloppy below.	*/
   asm("loop:");
   asm("stx %g0,[%o3]");		/* *(long *)p = 0		*/
   asm("cmp %o3,%o1");
   asm("bgu,pt %xcc, loop");	/* if (p > limit) goto loop	*/
     asm("add %o3,-8,%o3");	/* p -= 8 (delay slot) */
   asm("retl");
     asm("mov %o2,%sp");		/* Restore sp., delay slot	*/
 #else
   asm("mov %sp,%o2");		/* Save sp	*/
   asm("add %sp,-8,%o3");	/* p = sp-8	*/
   asm("clr %g1");		/* [g0,g1] = 0	*/
   asm("add %o1,-0x60,%sp");	/* Move sp out of the way,	*/
   				/* so that traps still work.	*/
   				/* Includes some extra words	*/
   				/* so we can be sloppy below.	*/
   asm("loop:");
   asm("std %g0,[%o3]");		/* *(long long *)p = 0	*/
   asm("cmp %o3,%o1");
   asm("bgu loop	");		/* if (p > limit) goto loop	*/
     asm("add %o3,-8,%o3");	/* p -= 8 (delay slot) */
   asm("retl");
     asm("mov %o2,%sp");		/* Restore sp., delay slot	*/
 #endif /* old SPARC */
   /* First argument = %o0 = return value */
 #   ifdef SVR4
       asm("	.GC_clear_stack_inner_end:");
       asm("	.size GC_clear_stack_inner,.GC_clear_stack_inner_end-GC_clear_stack_inner");
 #   endif

 # ifdef LINT
     /*ARGSUSED*/
     ptr_t GC_clear_stack_inner(arg, limit)
     ptr_t arg; word limit;
     { return(arg); }
 # endif
 #endif
	/*
	* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
	* 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, November 17, 1995 12:13 pm PST */
	# include "private/gc_priv.h"
	# include <stdio.h>
	# include <setjmp.h>
	# if defined(OS2) \|\| defined(CX_UX)
	# define _setjmp(b) setjmp(b)
	# define _longjmp(b,v) longjmp(b,v)
	# endif
	# ifdef AMIGA
	# ifndef __GNUC__
	# include <dos.h>
	# else
	# include <machine/reg.h>
	# endif
	# endif

	#if defined(RS6000) \|\| defined(POWERPC)
	# include <ucontext.h>
	#endif

	#if defined(__MWERKS__) && !defined(POWERPC)

	asm static void PushMacRegisters()
	{
	sub.w #4,sp // reserve space for one parameter.
	move.l a2,(sp)
	jsr GC_push_one
	move.l a3,(sp)
	jsr GC_push_one
	move.l a4,(sp)
	jsr GC_push_one
	# if !__option(a6frames)
	// <pcb> perhaps a6 should be pushed if stack frames are not being used.
	move.l a6,(sp)
	jsr GC_push_one
	# endif
	// skip a5 (globals), a6 (frame pointer), and a7 (stack pointer)
	move.l d2,(sp)
	jsr GC_push_one
	move.l d3,(sp)
	jsr GC_push_one
	move.l d4,(sp)
	jsr GC_push_one
	move.l d5,(sp)
	jsr GC_push_one
	move.l d6,(sp)
	jsr GC_push_one
	move.l d7,(sp)
	jsr GC_push_one
	add.w #4,sp // fix stack.
	rts
	}

	#endif /* __MWERKS__ */

	# if defined(SPARC) \|\| defined(IA64)
	/* Value returned from register flushing routine; either sp (SPARC) */
	/* or ar.bsp (IA64) */
	word GC_save_regs_ret_val;
	# endif

	/* Routine to mark from registers that are preserved by the C compiler. */
	/* This must be ported to every new architecture. There is a generic */
	/* version at the end, that is likely, but not guaranteed to work */
	/* on your architecture. Run the test_setjmp program to see whether */
	/* there is any chance it will work. */

	#if !defined(USE_GENERIC_PUSH_REGS) && !defined(USE_ASM_PUSH_REGS)
	#undef HAVE_PUSH_REGS
	void GC_push_regs()
	{
	# ifdef RT
	register long TMP_SP; /* must be bound to r11 */
	# endif

	# ifdef VAX
	/* VAX - generic code below does not work under 4.2 */
	/* r1 through r5 are caller save, and therefore */
	/* on the stack or dead. */
	asm("pushl r11"); asm("calls $1,_GC_push_one");
	asm("pushl r10"); asm("calls $1,_GC_push_one");
	asm("pushl r9"); asm("calls $1,_GC_push_one");
	asm("pushl r8"); asm("calls $1,_GC_push_one");
	asm("pushl r7"); asm("calls $1,_GC_push_one");
	asm("pushl r6"); asm("calls $1,_GC_push_one");
	# define HAVE_PUSH_REGS
	# endif
	# if defined(M68K) && (defined(SUNOS4) \|\| defined(NEXT))
	/* M68K SUNOS - could be replaced by generic code */
	/* a0, a1 and d1 are caller save */
	/* and therefore are on stack or dead. */

	asm("subqw #0x4,sp"); /* allocate word on top of stack */

	asm("movl a2,sp@"); asm("jbsr _GC_push_one");
	asm("movl a3,sp@"); asm("jbsr _GC_push_one");
	asm("movl a4,sp@"); asm("jbsr _GC_push_one");
	asm("movl a5,sp@"); asm("jbsr _GC_push_one");
	/* Skip frame pointer and stack pointer */
	asm("movl d1,sp@"); asm("jbsr _GC_push_one");
	asm("movl d2,sp@"); asm("jbsr _GC_push_one");
	asm("movl d3,sp@"); asm("jbsr _GC_push_one");
	asm("movl d4,sp@"); asm("jbsr _GC_push_one");
	asm("movl d5,sp@"); asm("jbsr _GC_push_one");
	asm("movl d6,sp@"); asm("jbsr _GC_push_one");
	asm("movl d7,sp@"); asm("jbsr _GC_push_one");

	asm("addqw #0x4,sp"); /* put stack back where it was */
	# define HAVE_PUSH_REGS
	# endif

	# if defined(M68K) && defined(HP)
	/* M68K HP - could be replaced by generic code */
	/* a0, a1 and d1 are caller save. */

	asm("subq.w &0x4,%sp"); /* allocate word on top of stack */

	asm("mov.l %a2,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %a3,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %a4,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %a5,(%sp)"); asm("jsr _GC_push_one");
	/* Skip frame pointer and stack pointer */
	asm("mov.l %d1,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d2,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d3,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d4,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d5,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d6,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d7,(%sp)"); asm("jsr _GC_push_one");

	asm("addq.w &0x4,%sp"); /* put stack back where it was */
	# define HAVE_PUSH_REGS
	# endif /* M68K HP */

	# if defined(M68K) && defined(AMIGA)
	/* AMIGA - could be replaced by generic code */
	/* a0, a1, d0 and d1 are caller save */

	# ifdef __GNUC__
	asm("subq.w &0x4,%sp"); /* allocate word on top of stack */

	asm("mov.l %a2,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %a3,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %a4,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %a5,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %a6,(%sp)"); asm("jsr _GC_push_one");
	/* Skip frame pointer and stack pointer */
	asm("mov.l %d2,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d3,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d4,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d5,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d6,(%sp)"); asm("jsr _GC_push_one");
	asm("mov.l %d7,(%sp)"); asm("jsr _GC_push_one");

	asm("addq.w &0x4,%sp"); /* put stack back where it was */
	# define HAVE_PUSH_REGS
	# else /* !__GNUC__ */
	GC_push_one(getreg(REG_A2));
	GC_push_one(getreg(REG_A3));
	# ifndef __SASC
	/* Can probably be changed to #if 0 -Kjetil M. (a4=globals)*/
	GC_push_one(getreg(REG_A4));
	# endif
	GC_push_one(getreg(REG_A5));
	GC_push_one(getreg(REG_A6));
	/* Skip stack pointer */
	GC_push_one(getreg(REG_D2));
	GC_push_one(getreg(REG_D3));
	GC_push_one(getreg(REG_D4));
	GC_push_one(getreg(REG_D5));
	GC_push_one(getreg(REG_D6));
	GC_push_one(getreg(REG_D7));
	# define HAVE_PUSH_REGS
	# endif /* !__GNUC__ */
	# endif /* AMIGA */

	# if defined(M68K) && defined(MACOS)
	# if defined(THINK_C)
	# define PushMacReg(reg) \
	move.l reg,(sp) \
	jsr GC_push_one
	asm {
	sub.w #4,sp ; reserve space for one parameter.
	PushMacReg(a2);
	PushMacReg(a3);
	PushMacReg(a4);
	; skip a5 (globals), a6 (frame pointer), and a7 (stack pointer)
	PushMacReg(d2);
	PushMacReg(d3);
	PushMacReg(d4);
	PushMacReg(d5);
	PushMacReg(d6);
	PushMacReg(d7);
	add.w #4,sp ; fix stack.
	}
	# define HAVE_PUSH_REGS
	# undef PushMacReg
	# endif /* THINK_C */
	# if defined(__MWERKS__)
	PushMacRegisters();
	# define HAVE_PUSH_REGS
	# endif /* __MWERKS__ */
	# endif /* MACOS */

	# if defined(I386) &&!defined(OS2) &&!defined(SVR4) \
	&& (defined(__MINGW32__) \|\| !defined(MSWIN32)) \
	&& !defined(SCO) && !defined(SCO_ELF) \
	&& !(defined(LINUX) && defined(__ELF__)) \
	&& !(defined(FREEBSD) && defined(__ELF__)) \
	&& !(defined(NETBSD) && defined(__ELF__)) \
	&& !(defined(OPENBSD) && defined(__ELF__)) \
	&& !(defined(BEOS) && defined(__ELF__)) \
	&& !defined(DOS4GW) && !defined(HURD)
	/* I386 code, generic code does not appear to work */
	/* It does appear to work under OS2, and asms dont */
	/* This is used for some 38g UNIX variants and for CYGWIN32 */
	asm("pushl %eax"); asm("call _GC_push_one"); asm("addl $4,%esp");
	asm("pushl %ecx"); asm("call _GC_push_one"); asm("addl $4,%esp");
	asm("pushl %edx"); asm("call _GC_push_one"); asm("addl $4,%esp");
	asm("pushl %ebp"); asm("call _GC_push_one"); asm("addl $4,%esp");
	asm("pushl %esi"); asm("call _GC_push_one"); asm("addl $4,%esp");
	asm("pushl %edi"); asm("call _GC_push_one"); asm("addl $4,%esp");
	asm("pushl %ebx"); asm("call _GC_push_one"); asm("addl $4,%esp");
	# define HAVE_PUSH_REGS
	# endif

	# if ( defined(I386) && defined(LINUX) && defined(__ELF__) ) \
	\|\| ( defined(I386) && defined(FREEBSD) && defined(__ELF__) ) \
	\|\| ( defined(I386) && defined(NETBSD) && defined(__ELF__) ) \
	\|\| ( defined(I386) && defined(OPENBSD) && defined(__ELF__) ) \
	\|\| ( defined(I386) && defined(HURD) && defined(__ELF__) ) \
	\|\| ( defined(I386) && defined(DGUX) )

	/* This is modified for Linux with ELF (Note: _ELF_ only) */
	/* This section handles FreeBSD with ELF. */
	/* Eax is caller-save and dead here. Other caller-save */
	/* registers could also be skipped. We assume there are no */
	/* pointers in MMX registers, etc. */
	/* We combine instructions in a single asm to prevent gcc from */
	/* inserting code in the middle. */
	asm("pushl %ecx; call GC_push_one; addl $4,%esp");
	asm("pushl %edx; call GC_push_one; addl $4,%esp");
	asm("pushl %ebp; call GC_push_one; addl $4,%esp");
	asm("pushl %esi; call GC_push_one; addl $4,%esp");
	asm("pushl %edi; call GC_push_one; addl $4,%esp");
	asm("pushl %ebx; call GC_push_one; addl $4,%esp");
	# define HAVE_PUSH_REGS
	# endif

	# if ( defined(I386) && defined(BEOS) && defined(__ELF__) )
	/* As far as I can understand from */
	/* http://www.beunited.org/articles/jbq/nasm.shtml, */
	/* only ebp, esi, edi and ebx are not scratch. How MMX */
	/* etc. registers should be treated, I have no idea. */
	asm("pushl %ebp; call GC_push_one; addl $4,%esp");
	asm("pushl %esi; call GC_push_one; addl $4,%esp");
	asm("pushl %edi; call GC_push_one; addl $4,%esp");
	asm("pushl %ebx; call GC_push_one; addl $4,%esp");
	# define HAVE_PUSH_REGS
	# endif

	# if defined(I386) && defined(MSWIN32) && !defined(__MINGW32__) \
	&& !defined(USE_GENERIC)
	/* I386 code, Microsoft variant */
	__asm push eax
	__asm call GC_push_one
	__asm add esp,4
	__asm push ebx
	__asm call GC_push_one
	__asm add esp,4
	__asm push ecx
	__asm call GC_push_one
	__asm add esp,4
	__asm push edx
	__asm call GC_push_one
	__asm add esp,4
	__asm push ebp
	__asm call GC_push_one
	__asm add esp,4
	__asm push esi
	__asm call GC_push_one
	__asm add esp,4
	__asm push edi
	__asm call GC_push_one
	__asm add esp,4
	# define HAVE_PUSH_REGS
	# endif

	# if defined(I386) && (defined(SVR4) \|\| defined(SCO) \|\| defined(SCO_ELF))
	/* I386 code, SVR4 variant, generic code does not appear to work */
	asm("pushl %eax"); asm("call GC_push_one"); asm("addl $4,%esp");
	asm("pushl %ebx"); asm("call GC_push_one"); asm("addl $4,%esp");
	asm("pushl %ecx"); asm("call GC_push_one"); asm("addl $4,%esp");
	asm("pushl %edx"); asm("call GC_push_one"); asm("addl $4,%esp");
	asm("pushl %ebp"); asm("call GC_push_one"); asm("addl $4,%esp");
	asm("pushl %esi"); asm("call GC_push_one"); asm("addl $4,%esp");
	asm("pushl %edi"); asm("call GC_push_one"); asm("addl $4,%esp");
	# define HAVE_PUSH_REGS
	# endif

	# ifdef NS32K
	asm ("movd r3, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
	asm ("movd r4, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
	asm ("movd r5, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
	asm ("movd r6, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
	asm ("movd r7, tos"); asm ("bsr ?_GC_push_one"); asm ("adjspb $-4");
	# define HAVE_PUSH_REGS
	# endif

	# if defined(SPARC)
	GC_save_regs_ret_val = GC_save_regs_in_stack();
	# define HAVE_PUSH_REGS
	# endif

	# ifdef RT
	GC_push_one(TMP_SP); /* GC_push_one from r11 */

	asm("cas r11, r6, r0"); GC_push_one(TMP_SP); /* r6 */
	asm("cas r11, r7, r0"); GC_push_one(TMP_SP); /* through */
	asm("cas r11, r8, r0"); GC_push_one(TMP_SP); /* r10 */
	asm("cas r11, r9, r0"); GC_push_one(TMP_SP);
	asm("cas r11, r10, r0"); GC_push_one(TMP_SP);

	asm("cas r11, r12, r0"); GC_push_one(TMP_SP); /* r12 */
	asm("cas r11, r13, r0"); GC_push_one(TMP_SP); /* through */
	asm("cas r11, r14, r0"); GC_push_one(TMP_SP); /* r15 */
	asm("cas r11, r15, r0"); GC_push_one(TMP_SP);
	# define HAVE_PUSH_REGS
	# endif

	# if defined(M68K) && defined(SYSV)
	/* Once again similar to SUN and HP, though setjmp appears to work.
	--Parag
	*/
	# ifdef __GNUC__
	asm("subqw #0x4,%sp"); /* allocate word on top of stack */

	asm("movl %a2,%sp@"); asm("jbsr GC_push_one");
	asm("movl %a3,%sp@"); asm("jbsr GC_push_one");
	asm("movl %a4,%sp@"); asm("jbsr GC_push_one");
	asm("movl %a5,%sp@"); asm("jbsr GC_push_one");
	/* Skip frame pointer and stack pointer */
	asm("movl %d1,%sp@"); asm("jbsr GC_push_one");
	asm("movl %d2,%sp@"); asm("jbsr GC_push_one");
	asm("movl %d3,%sp@"); asm("jbsr GC_push_one");
	asm("movl %d4,%sp@"); asm("jbsr GC_push_one");
	asm("movl %d5,%sp@"); asm("jbsr GC_push_one");
	asm("movl %d6,%sp@"); asm("jbsr GC_push_one");
	asm("movl %d7,%sp@"); asm("jbsr GC_push_one");

	asm("addqw #0x4,%sp"); /* put stack back where it was */
	# define HAVE_PUSH_REGS
	# else /* !__GNUC__*/
	asm("subq.w &0x4,%sp"); /* allocate word on top of stack */

	asm("mov.l %a2,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %a3,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %a4,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %a5,(%sp)"); asm("jsr GC_push_one");
	/* Skip frame pointer and stack pointer */
	asm("mov.l %d1,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %d2,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %d3,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %d4,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %d5,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %d6,(%sp)"); asm("jsr GC_push_one");
	asm("mov.l %d7,(%sp)"); asm("jsr GC_push_one");

	asm("addq.w &0x4,%sp"); /* put stack back where it was */
	# define HAVE_PUSH_REGS
	# endif /* !__GNUC__ */
	# endif /* M68K/SYSV */

	# if defined(PJ)
	{
	register int * sp asm ("optop");
	extern int *__libc_stack_end;

	GC_push_all_stack (sp, __libc_stack_end);
	# define HAVE_PUSH_REGS
	/* Isn't this redundant with the code to push the stack? */
	}
	# endif

	/* other machines... */
	# if !defined(HAVE_PUSH_REGS)
	--> We just generated an empty GC_push_regs, which
	--> is almost certainly broken. Try defining
	--> USE_GENERIC_PUSH_REGS instead.
	# endif
	}
	#endif /* !USE_GENERIC_PUSH_REGS && !USE_ASM_PUSH_REGS */

	void GC_with_callee_saves_pushed(fn, arg)
	void (*fn)();
	ptr_t arg;
	{
	word dummy;

	# if defined(USE_GENERIC_PUSH_REGS)
	# ifdef HAVE_BUILTIN_UNWIND_INIT
	/* This was suggested by Richard Henderson as the way to */
	/* force callee-save registers and register windows onto */
	/* the stack. */
	__builtin_unwind_init();
	# else /* !HAVE_BUILTIN_UNWIND_INIT */
	# if defined(RS6000) \|\| defined(POWERPC)
	/* FIXME: RS6000 means AIX. */
	/* This should probably be used in all Posix/non-gcc */
	/* settings. We defer that change to minimize risk. */
	ucontext_t ctxt;
	getcontext(&ctxt);
	# else
	/* Generic code */
	/* The idea is due to Parag Patel at HP. */
	/* We're not sure whether he would like */
	/* to be he acknowledged for it or not. */
	jmp_buf regs;
	register word * i = (word *) regs;
	register ptr_t lim = (ptr_t)(regs) + (sizeof regs);

	/* Setjmp doesn't always clear all of the buffer. */
	/* That tends to preserve garbage. Clear it. */
	for (; (char *)i < lim; i++) {
	*i = 0;
	}
	# if defined(MSWIN32) \|\| defined(MSWINCE) \
	\|\| defined(UTS4) \|\| defined(LINUX) \|\| defined(EWS4800)
	(void) setjmp(regs);
	# else
	(void) _setjmp(regs);
	/* We don't want to mess with signals. According to */
	/* SUSV3, setjmp() may or may not save signal mask. */
	/* _setjmp won't, but is less portable. */
	# endif
	# endif /* !AIX ... */
	# endif /* !HAVE_BUILTIN_UNWIND_INIT */
	# else
	# if defined(PTHREADS) && !defined(MSWIN32) /* !USE_GENERIC_PUSH_REGS */
	/* We may still need this to save thread contexts. */
	ucontext_t ctxt;
	getcontext(&ctxt);
	# else /* Shouldn't be needed */
	ABORT("Unexpected call to GC_with_callee_saves_pushed");
	# endif
	# endif
	# if (defined(SPARC) && !defined(HAVE_BUILTIN_UNWIND_INIT)) \
	\|\| defined(IA64)
	/* On a register window machine, we need to save register */
	/* contents on the stack for this to work. The setjmp */
	/* is probably not needed on SPARC, since pointers are */
	/* only stored in windowed or scratch registers. It is */
	/* needed on IA64, since some non-windowed registers are */
	/* preserved. */
	{
	GC_save_regs_ret_val = GC_save_regs_in_stack();
	/* On IA64 gcc, could use __builtin_ia64_flushrs() and */
	/* __builtin_ia64_flushrs(). The latter will be done */
	/* implicitly by __builtin_unwind_init() for gcc3.0.1 */
	/* and later. */
	}
	# endif
	fn(arg);
	/* Strongly discourage the compiler from treating the above */
	/* as a tail-call, since that would pop the register */
	/* contents before we get a chance to look at them. */
	GC_noop1((word)(&dummy));
	}

	#if defined(USE_GENERIC_PUSH_REGS)
	void GC_generic_push_regs(cold_gc_frame)
	ptr_t cold_gc_frame;
	{
	GC_with_callee_saves_pushed(GC_push_current_stack, cold_gc_frame);
	}
	#endif /* USE_GENERIC_PUSH_REGS */

	/* On register window machines, we need a way to force registers into */
	/* the stack. Return sp. */
	# ifdef SPARC
	asm(" .seg \"text\"");
	# if defined(SVR4) \|\| defined(NETBSD) \|\| defined(FREEBSD)
	asm(" .globl GC_save_regs_in_stack");
	asm("GC_save_regs_in_stack:");
	asm(" .type GC_save_regs_in_stack,#function");
	# else
	asm(" .globl _GC_save_regs_in_stack");
	asm("_GC_save_regs_in_stack:");
	# endif
	# if defined(__arch64__) \|\| defined(__sparcv9)
	asm(" save %sp,-128,%sp");
	asm(" flushw");
	asm(" ret");
	asm(" restore %sp,2047+128,%o0");
	# else
	asm(" ta 0x3 ! ST_FLUSH_WINDOWS");
	asm(" retl");
	asm(" mov %sp,%o0");
	# endif
	# ifdef SVR4
	asm(" .GC_save_regs_in_stack_end:");
	asm(" .size GC_save_regs_in_stack,.GC_save_regs_in_stack_end-GC_save_regs_in_stack");
	# endif
	# ifdef LINT
	word GC_save_regs_in_stack() { return(0 /* sp really */);}
	# endif
	# endif

	/* On IA64, we also need to flush register windows. But they end */
	/* up on the other side of the stack segment. */
	/* Returns the backing store pointer for the register stack. */
	/* We now implement this as a separate assembly file, since inline */
	/* assembly code here doesn't work with either the Intel or HP */
	/* compilers. */
	# if 0
	# ifdef LINUX
	asm(" .text");
	asm(" .psr abi64");
	asm(" .psr lsb");
	asm(" .lsb");
	asm("");
	asm(" .text");
	asm(" .align 16");
	asm(" .global GC_save_regs_in_stack");
	asm(" .proc GC_save_regs_in_stack");
	asm("GC_save_regs_in_stack:");
	asm(" .body");
	asm(" flushrs");
	asm(" ;;");
	asm(" mov r8=ar.bsp");
	asm(" br.ret.sptk.few rp");
	asm(" .endp GC_save_regs_in_stack");
	# endif /* LINUX */
	# if 0 /* Other alternatives that don't work on HP/UX */
	word GC_save_regs_in_stack() {
	# if USE_BUILTINS
	__builtin_ia64_flushrs();
	return __builtin_ia64_bsp();
	# else
	# ifdef HPUX
	_asm(" flushrs");
	_asm(" ;;");
	_asm(" mov r8=ar.bsp");
	_asm(" br.ret.sptk.few rp");
	# else
	asm(" flushrs");
	asm(" ;;");
	asm(" mov r8=ar.bsp");
	asm(" br.ret.sptk.few rp");
	# endif
	# endif
	}
	# endif
	# endif

	/* GC_clear_stack_inner(arg, limit) clears stack area up to limit and */
	/* returns arg. Stack clearing is crucial on SPARC, so we supply */
	/* an assembly version that's more careful. Assumes limit is hotter */
	/* than sp, and limit is 8 byte aligned. */
	#if defined(ASM_CLEAR_CODE)
	#ifndef SPARC
	--> fix it
	#endif
	# ifdef SUNOS4
	asm(".globl _GC_clear_stack_inner");
	asm("_GC_clear_stack_inner:");
	# else
	asm(".globl GC_clear_stack_inner");
	asm("GC_clear_stack_inner:");
	asm(".type GC_save_regs_in_stack,#function");
	# endif
	#if defined(__arch64__) \|\| defined(__sparcv9)
	asm("mov %sp,%o2"); /* Save sp */
	asm("add %sp,2047-8,%o3"); /* p = sp+bias-8 */
	asm("add %o1,-2047-192,%sp"); /* Move sp out of the way, */
	/* so that traps still work. */
	/* Includes some extra words */
	/* so we can be sloppy below. */
	asm("loop:");
	asm("stx %g0,[%o3]"); /* (long )p = 0 */
	asm("cmp %o3,%o1");
	asm("bgu,pt %xcc, loop"); /* if (p > limit) goto loop */
	asm("add %o3,-8,%o3"); /* p -= 8 (delay slot) */
	asm("retl");
	asm("mov %o2,%sp"); /* Restore sp., delay slot */
	#else
	asm("mov %sp,%o2"); /* Save sp */
	asm("add %sp,-8,%o3"); /* p = sp-8 */
	asm("clr %g1"); /* [g0,g1] = 0 */
	asm("add %o1,-0x60,%sp"); /* Move sp out of the way, */
	/* so that traps still work. */
	/* Includes some extra words */
	/* so we can be sloppy below. */
	asm("loop:");
	asm("std %g0,[%o3]"); /* (long long )p = 0 */
	asm("cmp %o3,%o1");
	asm("bgu loop "); /* if (p > limit) goto loop */
	asm("add %o3,-8,%o3"); /* p -= 8 (delay slot) */
	asm("retl");
	asm("mov %o2,%sp"); /* Restore sp., delay slot */
	#endif /* old SPARC */
	/* First argument = %o0 = return value */
	# ifdef SVR4
	asm(" .GC_clear_stack_inner_end:");
	asm(" .size GC_clear_stack_inner,.GC_clear_stack_inner_end-GC_clear_stack_inner");
	# endif

	# ifdef LINT
	/ARGSUSED/
	ptr_t GC_clear_stack_inner(arg, limit)
	ptr_t arg; word limit;
	{ return(arg); }
	# endif
	#endif