2 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3 * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
5 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
6 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
8 * Permission is hereby granted to use or copy this program
9 * for any purpose, provided the above notices are retained on all copies.
10 * Permission to modify the code and to distribute modified code is granted,
11 * provided the above notices are retained, and a notice that the code was
12 * modified is included with the above copyright notice.
14 /* Boehm, November 17, 1995 12:13 pm PST */
15 # include "private/gc_priv.h"
18 # if defined(OS2) || defined(CX_UX)
19 # define _setjmp(b) setjmp(b)
20 # define _longjmp(b,v) longjmp(b,v)
26 # include <machine/reg.h>
30 #if defined(__MWERKS__) && !defined(POWERPC)
32 asm static void PushMacRegisters()
34 sub.w #4,sp // reserve space for one parameter.
41 # if !__option(a6frames)
42 // <pcb> perhaps a6 should be pushed if stack frames are not being used.
46 // skip a5 (globals), a6 (frame pointer), and a7 (stack pointer)
59 add.w #4,sp // fix stack.
63 #endif /* __MWERKS__ */
65 # if defined(SPARC) || defined(IA64)
66 /* Value returned from register flushing routine; either sp (SPARC) */
67 /* or ar.bsp (IA64) */
68 ptr_t GC_save_regs_ret_val;
71 /* Routine to mark from registers that are preserved by the C compiler. */
72 /* This must be ported to every new architecture. It is not optional, */
73 /* and should not be used on platforms that are either UNIX-like, or */
74 /* require thread support. */
78 #if defined(USE_ASM_PUSH_REGS)
79 # define HAVE_PUSH_REGS
80 #else /* No asm implementation */
83 # if defined(M68K) && defined(AMIGA)
84 /* AMIGA - could be replaced by generic code */
85 /* a0, a1, d0 and d1 are caller save */
88 asm("subq.w &0x4,%sp"); /* allocate word on top of stack */
90 asm("mov.l %a2,(%sp)"); asm("jsr _GC_push_one");
91 asm("mov.l %a3,(%sp)"); asm("jsr _GC_push_one");
92 asm("mov.l %a4,(%sp)"); asm("jsr _GC_push_one");
93 asm("mov.l %a5,(%sp)"); asm("jsr _GC_push_one");
94 asm("mov.l %a6,(%sp)"); asm("jsr _GC_push_one");
95 /* Skip frame pointer and stack pointer */
96 asm("mov.l %d2,(%sp)"); asm("jsr _GC_push_one");
97 asm("mov.l %d3,(%sp)"); asm("jsr _GC_push_one");
98 asm("mov.l %d4,(%sp)"); asm("jsr _GC_push_one");
99 asm("mov.l %d5,(%sp)"); asm("jsr _GC_push_one");
100 asm("mov.l %d6,(%sp)"); asm("jsr _GC_push_one");
101 asm("mov.l %d7,(%sp)"); asm("jsr _GC_push_one");
103 asm("addq.w &0x4,%sp"); /* put stack back where it was */
104 # define HAVE_PUSH_REGS
105 # else /* !__GNUC__ */
106 GC_push_one(getreg(REG_A2));
107 GC_push_one(getreg(REG_A3));
109 /* Can probably be changed to #if 0 -Kjetil M. (a4=globals)*/
110 GC_push_one(getreg(REG_A4));
112 GC_push_one(getreg(REG_A5));
113 GC_push_one(getreg(REG_A6));
114 /* Skip stack pointer */
115 GC_push_one(getreg(REG_D2));
116 GC_push_one(getreg(REG_D3));
117 GC_push_one(getreg(REG_D4));
118 GC_push_one(getreg(REG_D5));
119 GC_push_one(getreg(REG_D6));
120 GC_push_one(getreg(REG_D7));
121 # define HAVE_PUSH_REGS
122 # endif /* !__GNUC__ */
125 # if defined(M68K) && defined(MACOS)
126 # if defined(THINK_C)
127 # define PushMacReg(reg) \
131 sub.w #4,sp ; reserve space for one parameter.
135 ; skip a5 (globals), a6 (frame pointer), and a7 (stack pointer)
142 add.w #4,sp ; fix stack.
144 # define HAVE_PUSH_REGS
146 # endif /* THINK_C */
147 # if defined(__MWERKS__)
149 # define HAVE_PUSH_REGS
150 # endif /* __MWERKS__ */
153 #endif /* !USE_ASM_PUSH_REGS */
155 #if defined(HAVE_PUSH_REGS) && defined(THREADS)
156 # error GC_push_regs cannot be used with threads
157 /* Would fail for GC_do_blocking. There are probably other safety */
159 # undef HAVE_PUSH_REGS
162 #if defined(UNIX_LIKE) && !defined(NO_GETCONTEXT) && \
163 (defined(DARWIN) || defined(HURD) || defined(ARM32) || defined(MIPS))
164 # define NO_GETCONTEXT
167 #if defined(LINUX) && defined(SPARC) && !defined(NO_GETCONTEXT)
168 # define NO_GETCONTEXT
171 #if !defined(HAVE_PUSH_REGS) && defined(UNIX_LIKE)
173 # ifndef NO_GETCONTEXT
174 # include <ucontext.h>
178 /* Ensure that either registers are pushed, or callee-save registers */
179 /* are somewhere on the stack, and then call fn(arg, ctxt). */
180 /* ctxt is either a pointer to a ucontext_t we generated, or NULL. */
181 void GC_with_callee_saves_pushed(void (*fn)(ptr_t, void *),
187 # if defined(HAVE_PUSH_REGS)
189 # elif defined(UNIX_LIKE) && !defined(NO_GETCONTEXT)
190 /* Older versions of Darwin seem to lack getcontext(). */
191 /* ARM and MIPS Linux often doesn't support a real */
194 if (getcontext(&ctxt) < 0)
195 ABORT ("Getcontext failed: Use another register retrieval method?");
197 # if defined(SPARC) || defined(IA64)
198 /* On a register window machine, we need to save register */
199 /* contents on the stack for this to work. This may already be */
200 /* subsumed by the getcontext() call. */
202 GC_save_regs_ret_val = GC_save_regs_in_stack();
204 # endif /* register windows. */
205 # elif defined(HAVE_BUILTIN_UNWIND_INIT) && \
206 !(defined(POWERPC) && defined(DARWIN))
207 /* This was suggested by Richard Henderson as the way to */
208 /* force callee-save registers and register windows onto */
210 /* Mark Sibly points out that this doesn't seem to work */
211 /* on MacOS 10.3.9/PowerPC. */
212 __builtin_unwind_init();
213 # else /* !HAVE_BUILTIN_UNWIND_INIT && !UNIX_LIKE */
214 /* && !HAVE_PUSH_REGS */
216 /* The idea is due to Parag Patel at HP. */
217 /* We're not sure whether he would like */
218 /* to be he acknowledged for it or not. */
220 register word * i = (word *) regs;
221 register ptr_t lim = (ptr_t)(regs) + (sizeof regs);
223 /* Setjmp doesn't always clear all of the buffer. */
224 /* That tends to preserve garbage. Clear it. */
225 for (; (char *)i < lim; i++) {
228 # if defined(MSWIN32) || defined(MSWINCE) \
229 || defined(UTS4) || defined(LINUX) || defined(EWS4800)
232 (void) _setjmp(regs);
233 /* We don't want to mess with signals. According to */
234 /* SUSV3, setjmp() may or may not save signal mask. */
235 /* _setjmp won't, but is less portable. */
237 # endif /* !HAVE_PUSH_REGS ... */
238 /* FIXME: context here is sometimes just zero. At the moment the callees */
239 /* don't really need it. */
241 /* Strongly discourage the compiler from treating the above */
242 /* as a tail-call, since that would pop the register */
243 /* contents before we get a chance to look at them. */
244 GC_noop1((word)(&dummy));
247 #if defined(ASM_CLEAR_CODE)
250 ptr_t GC_clear_stack_inner(arg, limit)
251 ptr_t arg; word limit;
253 /* The real version is in a .S file */
255 #endif /* ASM_CLEAR_CODE */