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 (g_strdup_printf ("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)
179 guint8 *buf, *tramp, *code = NULL;
181 GSList *unwind_ops = NULL;
182 MonoJumpInfo *ji = NULL;
183 int max_code_len = 768;
185 /* AOT not supported on MIPS yet */
188 /* Now we'll create in 'buf' the MIPS trampoline code. This
189 is the trampoline code common to all methods */
191 code = buf = mono_global_codeman_reserve (max_code_len);
193 /* Allocate the stack frame, and save the return address */
194 mips_addiu (code, mips_sp, mips_sp, -STACK);
195 mips_sw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
197 /* we build the MonoLMF structure on the stack - see mini-mips.h */
198 /* offset of MonoLMF from sp */
199 lmf = STACK - sizeof (MonoLMF) - 8;
201 for (i = 0; i < MONO_MAX_IREGS; i++)
202 MIPS_SW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
203 for (i = 0; i < MONO_MAX_FREGS; i++)
204 MIPS_SWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
206 /* Set the magic number */
207 mips_load_const (code, mips_at, MIPS_LMF_MAGIC2);
208 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, magic));
211 mips_addiu (code, mips_at, mips_sp, STACK);
212 MIPS_SW (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[mips_sp]));
214 /* save method info (it was in t8) */
215 mips_sw (code, mips_t8, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, method));
217 /* save the IP (caller ip) */
218 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
219 mips_sw (code, mips_zero, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
221 mips_sw (code, mips_ra, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, eip));
224 /* jump to mono_get_lmf_addr here */
225 mips_load (code, mips_t9, mono_get_lmf_addr);
226 mips_jalr (code, mips_t9, mips_ra);
229 /* v0 now points at the (MonoLMF **) for the current thread */
231 /* new_lmf->lmf_addr = lmf_addr -- useful when unwinding */
232 mips_sw (code, mips_v0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
234 /* new_lmf->previous_lmf = *lmf_addr */
235 mips_lw (code, mips_at, mips_v0, 0);
236 mips_sw (code, mips_at, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
238 /* *(lmf_addr) = new_lmf */
239 mips_addiu (code, mips_at, mips_sp, lmf);
240 mips_sw (code, mips_at, mips_v0, 0);
243 * Now we're ready to call mips_magic_trampoline ().
246 /* Arg 1: pointer to registers so that the magic trampoline can
247 * access what we saved above
249 mips_addiu (code, mips_a0, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[0]));
251 /* Arg 2: code (next address to the instruction that called us) */
252 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
253 mips_move (code, mips_a1, mips_zero);
255 mips_lw (code, mips_a1, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
258 /* Arg 3: MonoMethod *method. */
259 if (tramp_type == MONO_TRAMPOLINE_GENERIC_CLASS_INIT)
260 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs [mips_a0]));
262 mips_lw (code, mips_a2, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, method));
264 /* Arg 4: Trampoline */
265 mips_move (code, mips_a3, mips_zero);
267 /* Now go to the trampoline */
268 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
269 mips_load (code, mips_t9, (guint32)tramp);
270 mips_jalr (code, mips_t9, mips_ra);
273 /* Code address is now in v0, move it to at */
274 mips_move (code, mips_at, mips_v0);
277 * Now unwind the MonoLMF
280 /* t0 = current_lmf->previous_lmf */
281 mips_lw (code, mips_t0, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, previous_lmf));
283 mips_lw (code, mips_t1, mips_sp, lmf + G_STRUCT_OFFSET(MonoLMF, lmf_addr));
284 /* (*lmf_addr) = previous_lmf */
285 mips_sw (code, mips_t0, mips_t1, 0);
287 /* Restore the callee-saved & argument registers */
288 for (i = 0; i < MONO_MAX_IREGS; i++) {
289 if ((MONO_ARCH_CALLEE_SAVED_REGS | MONO_ARCH_CALLEE_REGS | MIPS_ARG_REGS) & (1 << i))
290 MIPS_LW (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, iregs[i]));
292 for (i = 0; i < MONO_MAX_FREGS; i++)
293 MIPS_LWC1 (code, i, mips_sp, lmf + G_STRUCT_OFFSET (MonoLMF, fregs[i]));
295 /* Non-standard function epilogue. Instead of doing a proper
296 * return, we just jump to the compiled code.
298 /* Restore ra & stack pointer, and jump to the code */
300 if (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH)
301 mips_move (code, mips_v0, mips_at);
302 mips_lw (code, mips_ra, mips_sp, STACK + MIPS_RET_ADDR_OFFSET);
303 mips_addiu (code, mips_sp, mips_sp, STACK);
304 if (MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type))
305 mips_jr (code, mips_ra);
307 mips_jr (code, mips_at);
310 /* Flush instruction cache, since we've generated code */
311 mono_arch_flush_icache (buf, code - buf);
314 g_assert ((code - buf) <= max_code_len);
316 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT)
317 /* Initialize the nullified class init trampoline used in the AOT case */
318 nullified_class_init_trampoline = mono_arch_get_nullified_class_init_trampoline (NULL);
321 *info = mono_tramp_info_create (mono_get_generic_trampoline_name (tramp_type), buf, code - buf, ji, unwind_ops);
327 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
329 guint8 *code, *buf, *tramp;
331 tramp = mono_get_trampoline_code (tramp_type);
333 code = buf = mono_domain_code_reserve (domain, 32);
335 /* Prepare the jump to the generic trampoline code
336 * mono_arch_create_trampoline_code() knows we're putting this in t8
338 mips_load (code, mips_t8, arg1);
340 /* Now jump to the generic trampoline code */
341 mips_load (code, mips_at, tramp);
342 mips_jr (code, mips_at);
345 /* Flush instruction cache, since we've generated code */
346 mono_arch_flush_icache (buf, code - buf);
348 g_assert ((code - buf) <= 32);
351 *code_len = code - buf;
357 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
359 guint8 *code, *start;
362 MonoDomain *domain = mono_domain_get ();
366 start = code = mono_domain_code_reserve (domain, buf_len);
368 mips_load (code, MONO_ARCH_RGCTX_REG, mrgctx);
369 mips_load (code, mips_at, addr);
370 mips_jr (code, mips_at);
373 g_assert ((code - start) <= buf_len);
375 mono_arch_flush_icache (start, code - start);
381 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
387 guint8 **rgctx_null_jumps;
391 MonoJumpInfo *ji = NULL;
392 GSList *unwind_ops = NULL;
394 mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
395 index = MONO_RGCTX_SLOT_INDEX (slot);
397 index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
398 for (depth = 0; ; ++depth) {
399 int size = mono_class_rgctx_get_array_size (depth, mrgctx);
401 if (index < size - 1)
406 tramp_size = 64 + 16 * depth;
408 code = buf = mono_global_codeman_reserve (tramp_size);
410 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, mips_sp, 0);
412 rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
415 /* The vtable/mrgctx is in a0 */
416 g_assert (MONO_ARCH_VTABLE_REG == mips_a0);
419 mips_move (code, mips_a1, mips_a0);
421 /* load rgctx ptr from vtable */
422 g_assert (mips_is_imm16 (G_STRUCT_OFFSET (MonoVTable, runtime_generic_context)));
423 mips_lw (code, mips_a1, mips_a0, G_STRUCT_OFFSET (MonoVTable, runtime_generic_context));
424 /* is the rgctx ptr null? */
425 /* if yes, jump to actual trampoline */
426 rgctx_null_jumps [njumps ++] = code;
427 mips_beq (code, mips_a1, mips_zero, 0);
431 for (i = 0; i < depth; ++i) {
432 /* load ptr to next array */
433 if (mrgctx && i == 0) {
434 g_assert (mips_is_imm16 (MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT));
435 mips_lw (code, mips_a1, mips_a1, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT);
437 mips_lw (code, mips_a1, mips_a1, 0);
439 /* is the ptr null? */
440 /* if yes, jump to actual trampoline */
441 rgctx_null_jumps [njumps ++] = code;
442 mips_beq (code, mips_a1, mips_zero, 0);
447 g_assert (mips_is_imm16 (sizeof (gpointer) * (index + 1)));
448 mips_lw (code, mips_a1, mips_a1, sizeof (gpointer) * (index + 1));
449 /* is the slot null? */
450 /* if yes, jump to actual trampoline */
451 rgctx_null_jumps [njumps ++] = code;
452 mips_beq (code, mips_a1, mips_zero, 0);
454 /* otherwise return, result is in R1 */
455 mips_move (code, mips_v0, mips_a1);
456 mips_jr (code, mips_ra);
459 g_assert (njumps <= depth + 2);
460 for (i = 0; i < njumps; ++i)
461 mips_patch ((guint32*)rgctx_null_jumps [i], (guint32)code);
463 g_free (rgctx_null_jumps);
467 /* The vtable/mrgctx is still in a0 */
470 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
471 mips_load (code, mips_at, 0);
472 mips_jr (code, mips_at);
475 tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), &code_len);
476 mips_load (code, mips_at, tramp);
477 mips_jr (code, mips_at);
481 mono_arch_flush_icache (buf, code - buf);
483 g_assert (code - buf <= tramp_size);
486 *info = mono_tramp_info_create (mono_get_rgctx_fetch_trampoline_name (slot), buf, code - buf, ji, unwind_ops);
492 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
496 static int byte_offset = -1;
497 static guint8 bitmask;
501 GSList *unwind_ops = NULL;
502 MonoJumpInfo *ji = NULL;
506 code = buf = mono_global_codeman_reserve (tramp_size);
509 mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
511 /* if (!(vtable->initialized)) */
512 mips_lbu (code, mips_at, MONO_ARCH_VTABLE_REG, byte_offset);
513 g_assert (!(bitmask & 0xffff0000));
514 mips_andi (code, mips_at, mips_at, bitmask);
516 mips_beq (code, mips_at, mips_zero, 0);
518 /* Initialized case */
519 mips_jr (code, mips_ra);
522 /* Uninitialized case */
523 mips_patch ((guint32*)jump, (guint32)code);
526 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "specific_trampoline_generic_class_init");
527 mips_load (code, mips_at, 0);
528 mips_jr (code, mips_at);
531 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_GENERIC_CLASS_INIT, mono_get_root_domain (), &code_len);
532 mips_load (code, mips_at, tramp);
533 mips_jr (code, mips_at);
537 mono_arch_flush_icache (buf, code - buf);
539 g_assert (code - buf <= tramp_size);
542 *info = mono_tramp_info_create (g_strdup_printf ("generic_class_init_trampoline"), buf, code - buf, ji, unwind_ops);