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 STACK (4*IREG_SIZE + 8 + sizeof(MonoLMF) + 32)
115 mono_arch_nullify_plt_entry (guint8 *code, mgreg_t *regs)
117 if (mono_aot_only && !nullified_class_init_trampoline)
118 nullified_class_init_trampoline = mono_aot_get_trampoline ("nullified_class_init_trampoline");
120 mono_arch_patch_plt_entry (code, NULL, regs, nullified_class_init_trampoline);
124 mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
126 guint32 *code32 = (guint32*)code;
128 /* back up to the jal/jalr instruction */
131 /* Check for jal/jalr -- and NOP it out */
132 if ((((*code32)&0xfc000000) == 0x0c000000)
133 || (((*code32)&0xfc1f003f) == 0x00000009)) {
135 mono_arch_flush_icache ((gpointer)(code32 - 1), 4);
138 g_assert_not_reached ();
142 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
146 code = buf = mono_global_codeman_reserve (16);
148 mips_jr (code, mips_ra);
151 mono_arch_flush_icache (buf, code - buf);
154 *info = mono_tramp_info_create (g_strdup_printf ("nullified_class_init_trampoline"), buf, code - buf, NULL, NULL);
160 * Stack frame description when the generic trampoline is called.
162 * --------------------
164 * -------------------
165 * Saved FP registers 0-13
166 * -------------------
167 * Saved general registers 0-12
168 * -------------------
169 * param area for 3 args to mips_magic_trampoline
170 * -------------------
172 * -------------------
175 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
177 guint8 *buf, *tramp, *code = NULL;
179 GSList *unwind_ops = NULL;
180 MonoJumpInfo *ji = NULL;
181 int max_code_len = 768;
183 /* AOT not supported on MIPS yet */
186 /* Now we'll create in 'buf' the MIPS trampoline code. This
187 is the trampoline code common to all methods */
189 code = buf = mono_global_codeman_reserve (max_code_len);
191 /* Allocate the stack frame, and save the return address */
192 mips_addiu (code, mips_sp, mips_sp, -STACK);
193 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
195 /* we build the MonoLMF structure on the stack - see mini-mips.h */
196 /* offset of MonoLMF from sp */
197 lmf = STACK - sizeof (MonoLMF) - 8;
199 for (i = 0; i < MONO_MAX_IREGS; i++)
200 MIPS_SW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
201 for (i = 0; i < MONO_MAX_FREGS; i++)
202 MIPS_SWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
204 /* Set the magic number */
205 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
206 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
209 mips_addiu (code, mips_at, mips_sp, STACK);
210 MIPS_SW (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[mips_sp]));
212 /* save method info (it was in t8) */
213 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
215 /* save the IP (caller ip) */
216 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
217 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
219 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
222 /* jump to mono_get_lmf_addr here */
223 mips_load (code, mips_t9, mono_get_lmf_addr);
224 mips_jalr (code, mips_t9, mips_ra);
227 /* v0 now points at the (MonoLMF **) for the current thread */
229 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
230 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
232 /* new_lmf->previous_lmf = *lmf_addr */
233 mips_lw (code, mips_at, mips_v0, 0);
234 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
236 /* *(lmf_addr) = new_lmf */
237 mips_addiu (code, mips_at, mips_sp, lmf);
238 mips_sw (code, mips_at, mips_v0, 0);
241 * Now we're ready to call mips_magic_trampoline ().
244 /* Arg 1: pointer to registers so that the magic trampoline can
245 * access what we saved above
247 mips_addiu (code, mips_a0, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[0]));
249 /* Arg 2: code (next address to the instruction that called us) */
250 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
251 mips_move (code, mips_a1, mips_zero);
253 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
256 /* Arg 3: MonoMethod *method. */
257 if (tramp_type == MONO_TRAMPOLINE_GENERIC_CLASS_INIT)
258 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs [mips_a0]));
260 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
262 /* Arg 4: Trampoline */
263 mips_move (code, mips_a3, mips_zero);
265 /* Now go to the trampoline */
266 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
267 mips_load (code, mips_t9, (guint32)tramp);
268 mips_jalr (code, mips_t9, mips_ra);
271 /* Code address is now in v0, move it to at */
272 mips_move (code, mips_at, mips_v0);
275 * Now unwind the MonoLMF
278 /* t0 = current_lmf->previous_lmf */
279 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
281 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
282 /* (*lmf_addr) = previous_lmf */
283 mips_sw (code, mips_t0, mips_t1, 0);
285 /* Restore the callee-saved & argument registers */
286 for (i = 0; i < MONO_MAX_IREGS; i++) {
287 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
288 MIPS_LW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
290 for (i = 0; i < MONO_MAX_FREGS; i++)
291 MIPS_LWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
293 /* Non-standard function epilogue. Instead of doing a proper
294 * return, we just jump to the compiled code.
296 /* Restore ra & stack pointer, and jump to the code */
298 if (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH)
299 mips_move (code, mips_v0, mips_at);
300 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
301 mips_addiu (code, mips_sp, mips_sp, STACK);
302 if (MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type))
303 mips_jr (code, mips_ra);
305 mips_jr (code, mips_at);
308 /* Flush instruction cache, since we've generated code */
309 mono_arch_flush_icache (buf, code - buf);
312 g_assert ((code - buf) <= max_code_len);
314 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
315 /* Initialize the nullified class init trampoline used in the AOT case */
316 nullified_class_init_trampoline = mono_arch_get_nullified_class_init_trampoline (NULL);
319 *info = mono_tramp_info_create (mono_get_generic_trampoline_name (tramp_type), buf, code - buf, ji, unwind_ops);
325 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
327 guint8 *code, *buf, *tramp;
329 tramp = mono_get_trampoline_code (tramp_type);
331 code = buf = mono_domain_code_reserve (domain, 32);
333 /* Prepare the jump to the generic trampoline code
334 * mono_arch_create_trampoline_code() knows we're putting this in t8
336 mips_load (code, mips_t8, arg1);
338 /* Now jump to the generic trampoline code */
339 mips_load (code, mips_at, tramp);
340 mips_jr (code, mips_at);
343 /* Flush instruction cache, since we've generated code */
344 mono_arch_flush_icache (buf, code - buf);
346 g_assert ((code - buf) <= 32);
349 *code_len = code - buf;
355 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
357 guint8 *code, *start;
360 MonoDomain *domain = mono_domain_get ();
364 start = code = mono_domain_code_reserve (domain, buf_len);
366 mips_load (code, MONO_ARCH_RGCTX_REG, mrgctx);
367 mips_load (code, mips_at, addr);
368 mips_jr (code, mips_at);
371 g_assert ((code - start) <= buf_len);
373 mono_arch_flush_icache (start, code - start);
379 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
385 guint8 **rgctx_null_jumps;
389 MonoJumpInfo *ji = NULL;
390 GSList *unwind_ops = NULL;
392 mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
393 index = MONO_RGCTX_SLOT_INDEX (slot);
395 index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
396 for (depth = 0; ; ++depth) {
397 int size = mono_class_rgctx_get_array_size (depth, mrgctx);
399 if (index < size - 1)
404 tramp_size = 64 + 16 * depth;
406 code = buf = mono_global_codeman_reserve (tramp_size);
408 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, mips_sp, 0);
410 rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
413 /* The vtable/mrgctx is in a0 */
414 g_assert (MONO_ARCH_VTABLE_REG == mips_a0);
417 mips_move (code, mips_a1, mips_a0);
419 /* load rgctx ptr from vtable */
420 g_assert (mips_is_imm16 (G_STRUCT_OFFSET (MonoVTable, runtime_generic_context)));
421 mips_lw (code, mips_a1, mips_a0, G_STRUCT_OFFSET (MonoVTable, runtime_generic_context));
422 /* is the rgctx ptr null? */
423 /* if yes, jump to actual trampoline */
424 rgctx_null_jumps [njumps ++] = code;
425 mips_beq (code, mips_a1, mips_zero, 0);
429 for (i = 0; i < depth; ++i) {
430 /* load ptr to next array */
431 if (mrgctx && i == 0) {
432 g_assert (mips_is_imm16 (MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT));
433 mips_lw (code, mips_a1, mips_a1, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT);
435 mips_lw (code, mips_a1, mips_a1, 0);
437 /* is the ptr null? */
438 /* if yes, jump to actual trampoline */
439 rgctx_null_jumps [njumps ++] = code;
440 mips_beq (code, mips_a1, mips_zero, 0);
445 g_assert (mips_is_imm16 (sizeof (gpointer) * (index + 1)));
446 mips_lw (code, mips_a1, mips_a1, sizeof (gpointer) * (index + 1));
447 /* is the slot null? */
448 /* if yes, jump to actual trampoline */
449 rgctx_null_jumps [njumps ++] = code;
450 mips_beq (code, mips_a1, mips_zero, 0);
452 /* otherwise return, result is in R1 */
453 mips_move (code, mips_v0, mips_a1);
454 mips_jr (code, mips_ra);
457 g_assert (njumps <= depth + 2);
458 for (i = 0; i < njumps; ++i)
459 mips_patch ((guint32*)rgctx_null_jumps [i], (guint32)code);
461 g_free (rgctx_null_jumps);
465 /* The vtable/mrgctx is still in a0 */
468 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
469 mips_load (code, mips_at, 0);
470 mips_jr (code, mips_at);
473 tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), &code_len);
474 mips_load (code, mips_at, tramp);
475 mips_jr (code, mips_at);
479 mono_arch_flush_icache (buf, code - buf);
481 g_assert (code - buf <= tramp_size);
484 *info = mono_tramp_info_create (mono_get_rgctx_fetch_trampoline_name (slot), buf, code - buf, ji, unwind_ops);
490 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
494 static int byte_offset = -1;
495 static guint8 bitmask;
499 GSList *unwind_ops = NULL;
500 MonoJumpInfo *ji = NULL;
504 code = buf = mono_global_codeman_reserve (tramp_size);
507 mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
509 /* if (!(vtable->initialized)) */
510 mips_lbu (code, mips_at, MONO_ARCH_VTABLE_REG, byte_offset);
511 g_assert (!(bitmask & 0xffff0000));
512 mips_andi (code, mips_at, mips_at, bitmask);
514 mips_beq (code, mips_at, mips_zero, 0);
516 /* Initialized case */
517 mips_jr (code, mips_ra);
520 /* Uninitialized case */
521 mips_patch ((guint32*)jump, (guint32)code);
524 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "specific_trampoline_generic_class_init");
525 mips_load (code, mips_at, 0);
526 mips_jr (code, mips_at);
529 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_GENERIC_CLASS_INIT, mono_get_root_domain (), &code_len);
530 mips_load (code, mips_at, tramp);
531 mips_jr (code, mips_at);
535 mono_arch_flush_icache (buf, code - buf);
537 g_assert (code - buf <= tramp_size);
540 *info = mono_tramp_info_create (g_strdup_printf ("generic_class_init_trampoline"), buf, code - buf, ji, unwind_ops);