2 * tramp-mips.c: JIT trampoline code for MIPS
5 * Mark Mason (mason@broadcom.com)
7 * Based on tramp-ppc.c by:
8 * Dietmar Maurer (dietmar@ximian.com)
9 * Paolo Molaro (lupus@ximian.com)
10 * Carlos Valiente <yo@virutass.net>
13 * (C) 2001 Ximian, Inc.
19 #include <mono/metadata/appdomain.h>
20 #include <mono/metadata/marshal.h>
21 #include <mono/metadata/tabledefs.h>
22 #include <mono/arch/mips/mips-codegen.h>
25 #include "mini-mips.h"
27 static guint8* nullified_class_init_trampoline;
30 * get_unbox_trampoline:
32 * @addr: pointer to native code for @m
34 * when value type methods are called through the vtable we need to unbox the
35 * this argument. This method returns a pointer to a trampoline which does
36 * unboxing before calling the method
39 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
42 MonoDomain *domain = mono_domain_get ();
44 start = code = mono_domain_code_reserve (domain, 20);
46 mips_load (code, mips_t9, addr);
47 /* The this pointer is kept in a0 */
48 mips_addiu (code, mips_a0, mips_a0, sizeof (MonoObject));
49 mips_jr (code, mips_t9);
52 mono_arch_flush_icache (start, code - start);
53 g_assert ((code - start) <= 20);
54 /*g_print ("unbox trampoline at %d for %s:%s\n", this_pos, m->klass->name, m->name);
55 g_print ("unbox code is at %p for method at %p\n", start, addr);*/
61 mono_arch_patch_callsite (guint8 *method_start, guint8 *orig_code, guint8 *addr)
63 guint32 *code = (guint32*)orig_code;
65 /* Locate the address of the method-specific trampoline.
66 The call using the vtable slot that took the processing flow to
67 'arch_create_jit_trampoline' looks something like one of these:
77 On entry, 'code' points just after one of the above sequences.
81 if ((code[-2] >> 26) == 0x03) {
82 //g_print ("direct patching\n");
83 mips_patch ((code-2), (gsize)addr);
86 /* Look for the jalr */
87 if ((code[-2] & 0xfc1f003f) == 0x00000009) {
88 /* The lui / addiu / jalr case */
89 if ((code [-4] >> 26) == 0x0f && (code [-3] >> 26) == 0x09
90 && (code [-2] >> 26) == 0) {
91 mips_patch ((code-4), (gsize)addr);
95 g_print("error: bad patch at 0x%08x\n", code);
96 g_assert_not_reached ();
100 mono_arch_patch_plt_entry (guint8 *code, gpointer *got, mgreg_t *regs, guint8 *addr)
102 g_assert_not_reached ();
105 /* Stack size for trampoline function
106 * MIPS_MINIMAL_STACK_SIZE + 16 (args + alignment to mips_magic_trampoline)
107 * + MonoLMF + 14 fp regs + 13 gregs + alignment
108 * #define STACK (MIPS_MINIMAL_STACK_SIZE + 4 * sizeof (gulong) + sizeof (MonoLMF) + 14 * sizeof (double) + 13 * (sizeof (gulong)))
109 * STACK would be 444 for 32 bit darwin
112 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
114 #define STACK (int)(ALIGN_TO(4*IREG_SIZE + 8 + sizeof(MonoLMF) + 32, 8))
117 mono_arch_nullify_plt_entry (guint8 *code, mgreg_t *regs)
119 if (mono_aot_only && !nullified_class_init_trampoline)
120 nullified_class_init_trampoline = mono_aot_get_trampoline ("nullified_class_init_trampoline");
122 mono_arch_patch_plt_entry (code, NULL, regs, nullified_class_init_trampoline);
126 mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
128 guint32 *code32 = (guint32*)code;
130 /* back up to the jal/jalr instruction */
133 /* Check for jal/jalr -- and NOP it out */
134 if ((((*code32)&0xfc000000) == 0x0c000000)
135 || (((*code32)&0xfc1f003f) == 0x00000009)) {
137 mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
140 g_assert_not_reached ();
144 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
148 code = buf = mono_global_codeman_reserve (16);
150 mips_jr (code, mips_ra);
153 mono_arch_flush_icache (buf, code - buf);
156 *info = mono_tramp_info_create ("nullified_class_init_trampoline", buf, code - buf, NULL, NULL);
162 * Stack frame description when the generic trampoline is called.
164 * --------------------
166 * -------------------
167 * Saved FP registers 0-13
168 * -------------------
169 * Saved general registers 0-12
170 * -------------------
171 * param area for 3 args to mips_magic_trampoline
172 * -------------------
174 * -------------------
177 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
180 guint8 *buf, *tramp, *code = NULL;
182 GSList *unwind_ops = NULL;
183 MonoJumpInfo *ji = NULL;
184 int max_code_len = 768;
186 /* AOT not supported on MIPS yet */
189 /* Now we'll create in 'buf' the MIPS trampoline code. This
190 is the trampoline code common to all methods */
192 code = buf = mono_global_codeman_reserve (max_code_len);
194 /* Allocate the stack frame, and save the return address */
195 mips_addiu (code, mips_sp, mips_sp, -STACK);
196 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
198 /* we build the MonoLMF structure on the stack - see mini-mips.h */
199 /* offset of MonoLMF from sp */
200 lmf = STACK - sizeof (MonoLMF) - 8;
202 for (i = 0; i < MONO_MAX_IREGS; i++)
203 MIPS_SW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
204 for (i = 0; i < MONO_MAX_FREGS; i++)
205 MIPS_SWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
207 /* Set the magic number */
208 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
209 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
212 mips_addiu (code, mips_at, mips_sp, STACK);
213 MIPS_SW (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[mips_sp]));
215 /* save method info (it was in t8) */
216 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
218 /* save the IP (caller ip) */
219 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
220 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
222 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
225 /* jump to mono_get_lmf_addr here */
226 mips_load (code, mips_t9, mono_get_lmf_addr);
227 mips_jalr (code, mips_t9, mips_ra);
230 /* v0 now points at the (MonoLMF **) for the current thread */
232 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
233 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
235 /* new_lmf->previous_lmf = *lmf_addr */
236 mips_lw (code, mips_at, mips_v0, 0);
237 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
239 /* *(lmf_addr) = new_lmf */
240 mips_addiu (code, mips_at, mips_sp, lmf);
241 mips_sw (code, mips_at, mips_v0, 0);
244 * Now we're ready to call mips_magic_trampoline ().
247 /* Arg 1: pointer to registers so that the magic trampoline can
248 * access what we saved above
250 mips_addiu (code, mips_a0, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[0]));
252 /* Arg 2: code (next address to the instruction that called us) */
253 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
254 mips_move (code, mips_a1, mips_zero);
256 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
259 /* Arg 3: MonoMethod *method. */
260 if (tramp_type == MONO_TRAMPOLINE_GENERIC_CLASS_INIT)
261 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs [mips_a0]));
263 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
265 /* Arg 4: Trampoline */
266 mips_move (code, mips_a3, mips_zero);
268 /* Now go to the trampoline */
269 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
270 mips_load (code, mips_t9, (guint32)tramp);
271 mips_jalr (code, mips_t9, mips_ra);
274 /* Code address is now in v0, move it to at */
275 mips_move (code, mips_at, mips_v0);
278 * Now unwind the MonoLMF
281 /* t0 = current_lmf->previous_lmf */
282 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
284 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
285 /* (*lmf_addr) = previous_lmf */
286 mips_sw (code, mips_t0, mips_t1, 0);
288 /* Restore the callee-saved & argument registers */
289 for (i = 0; i < MONO_MAX_IREGS; i++) {
290 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
291 MIPS_LW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
293 for (i = 0; i < MONO_MAX_FREGS; i++)
294 MIPS_LWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
296 /* Non-standard function epilogue. Instead of doing a proper
297 * return, we just jump to the compiled code.
299 /* Restore ra & stack pointer, and jump to the code */
301 if (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH)
302 mips_move (code, mips_v0, mips_at);
303 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
304 mips_addiu (code, mips_sp, mips_sp, STACK);
305 if (MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type))
306 mips_jr (code, mips_ra);
308 mips_jr (code, mips_at);
311 /* Flush instruction cache, since we've generated code */
312 mono_arch_flush_icache (buf, code - buf);
315 g_assert ((code - buf) <= max_code_len);
317 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
318 /* Initialize the nullified class init trampoline used in the AOT case */
319 nullified_class_init_trampoline = mono_arch_get_nullified_class_init_trampoline (NULL);
322 tramp_name = mono_get_generic_trampoline_name (tramp_type);
323 *info = mono_tramp_info_create (tramp_name, buf, code - buf, ji, unwind_ops);
331 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
333 guint8 *code, *buf, *tramp;
335 tramp = mono_get_trampoline_code (tramp_type);
337 code = buf = mono_domain_code_reserve (domain, 32);
339 /* Prepare the jump to the generic trampoline code
340 * mono_arch_create_trampoline_code() knows we're putting this in t8
342 mips_load (code, mips_t8, arg1);
344 /* Now jump to the generic trampoline code */
345 mips_load (code, mips_at, tramp);
346 mips_jr (code, mips_at);
349 /* Flush instruction cache, since we've generated code */
350 mono_arch_flush_icache (buf, code - buf);
352 g_assert ((code - buf) <= 32);
355 *code_len = code - buf;
361 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
363 guint8 *code, *start;
366 MonoDomain *domain = mono_domain_get ();
370 start = code = mono_domain_code_reserve (domain, buf_len);
372 mips_load (code, MONO_ARCH_RGCTX_REG, mrgctx);
373 mips_load (code, mips_at, addr);
374 mips_jr (code, mips_at);
377 g_assert ((code - start) <= buf_len);
379 mono_arch_flush_icache (start, code - start);
385 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
391 guint8 **rgctx_null_jumps;
395 MonoJumpInfo *ji = NULL;
396 GSList *unwind_ops = NULL;
398 mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
399 index = MONO_RGCTX_SLOT_INDEX (slot);
401 index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
402 for (depth = 0; ; ++depth) {
403 int size = mono_class_rgctx_get_array_size (depth, mrgctx);
405 if (index < size - 1)
410 tramp_size = 64 + 16 * depth;
412 code = buf = mono_global_codeman_reserve (tramp_size);
414 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, mips_sp, 0);
416 rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
419 /* The vtable/mrgctx is in a0 */
420 g_assert (MONO_ARCH_VTABLE_REG == mips_a0);
423 mips_move (code, mips_a1, mips_a0);
425 /* load rgctx ptr from vtable */
426 g_assert (mips_is_imm16 (G_STRUCT_OFFSET (MonoVTable, runtime_generic_context)));
427 mips_lw (code, mips_a1, mips_a0, G_STRUCT_OFFSET (MonoVTable, runtime_generic_context));
428 /* is the rgctx ptr null? */
429 /* if yes, jump to actual trampoline */
430 rgctx_null_jumps [njumps ++] = code;
431 mips_beq (code, mips_a1, mips_zero, 0);
435 for (i = 0; i < depth; ++i) {
436 /* load ptr to next array */
437 if (mrgctx && i == 0) {
438 g_assert (mips_is_imm16 (MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT));
439 mips_lw (code, mips_a1, mips_a1, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT);
441 mips_lw (code, mips_a1, mips_a1, 0);
443 /* is the ptr null? */
444 /* if yes, jump to actual trampoline */
445 rgctx_null_jumps [njumps ++] = code;
446 mips_beq (code, mips_a1, mips_zero, 0);
451 g_assert (mips_is_imm16 (sizeof (gpointer) * (index + 1)));
452 mips_lw (code, mips_a1, mips_a1, sizeof (gpointer) * (index + 1));
453 /* is the slot null? */
454 /* if yes, jump to actual trampoline */
455 rgctx_null_jumps [njumps ++] = code;
456 mips_beq (code, mips_a1, mips_zero, 0);
458 /* otherwise return, result is in R1 */
459 mips_move (code, mips_v0, mips_a1);
460 mips_jr (code, mips_ra);
463 g_assert (njumps <= depth + 2);
464 for (i = 0; i < njumps; ++i)
465 mips_patch ((guint32*)rgctx_null_jumps [i], (guint32)code);
467 g_free (rgctx_null_jumps);
471 /* The vtable/mrgctx is still in a0 */
474 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
475 mips_load (code, mips_at, 0);
476 mips_jr (code, mips_at);
479 tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), &code_len);
480 mips_load (code, mips_at, tramp);
481 mips_jr (code, mips_at);
485 mono_arch_flush_icache (buf, code - buf);
487 g_assert (code - buf <= tramp_size);
490 char *name = mono_get_rgctx_fetch_trampoline_name (slot);
491 *info = mono_tramp_info_create (name, buf, code - buf, ji, unwind_ops);
499 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
503 static int byte_offset = -1;
504 static guint8 bitmask;
508 GSList *unwind_ops = NULL;
509 MonoJumpInfo *ji = NULL;
513 code = buf = mono_global_codeman_reserve (tramp_size);
516 mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
518 /* if (!(vtable->initialized)) */
519 mips_lbu (code, mips_at, MONO_ARCH_VTABLE_REG, byte_offset);
520 g_assert (!(bitmask & 0xffff0000));
521 mips_andi (code, mips_at, mips_at, bitmask);
523 mips_beq (code, mips_at, mips_zero, 0);
525 /* Initialized case */
526 mips_jr (code, mips_ra);
529 /* Uninitialized case */
530 mips_patch ((guint32*)jump, (guint32)code);
533 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "specific_trampoline_generic_class_init");
534 mips_load (code, mips_at, 0);
535 mips_jr (code, mips_at);
538 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_GENERIC_CLASS_INIT, mono_get_root_domain (), &code_len);
539 mips_load (code, mips_at, tramp);
540 mips_jr (code, mips_at);
544 mono_arch_flush_icache (buf, code - buf);
546 g_assert (code - buf <= tramp_size);
549 *info = mono_tramp_info_create ("generic_class_init_trampoline", buf, code - buf, ji, unwind_ops);