2 * tramp-arm.c: JIT trampoline code for ARM
5 * Paolo Molaro (lupus@ximian.com)
7 * (C) 2001-2003 Ximian, Inc.
8 * Copyright 2003-2011 Novell Inc
9 * Copyright 2011 Xamarin Inc
15 #include <mono/metadata/abi-details.h>
16 #include <mono/metadata/appdomain.h>
17 #include <mono/metadata/marshal.h>
18 #include <mono/metadata/tabledefs.h>
19 #include <mono/arch/arm/arm-codegen.h>
20 #include <mono/arch/arm/arm-vfp-codegen.h>
25 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
27 #ifdef USE_JUMP_TABLES
30 decode_imm16 (guint32 insn)
32 return (((insn >> 16) & 0xf) << 12) | (insn & 0xfff);
35 #define INSN_MASK 0xff00000
36 #define MOVW_MASK ((3 << 24) | (0 << 20))
37 #define MOVT_MASK ((3 << 24) | (4 << 20))
40 mono_arch_jumptable_entry_from_code (guint8 *code)
42 guint32 insn1 = ((guint32*)code) [0];
43 guint32 insn2 = ((guint32*)code) [1];
45 if (((insn1 & INSN_MASK) == MOVW_MASK) &&
46 ((insn2 & INSN_MASK) == MOVT_MASK) ) {
47 guint32 imm_lo = decode_imm16 (insn1);
48 guint32 imm_hi = decode_imm16 (insn2);
49 return (gpointer*) GUINT_TO_POINTER (imm_lo | (imm_hi << 16));
51 g_assert_not_reached ();
61 mono_arch_patch_callsite (guint8 *method_start, guint8 *code_ptr, guint8 *addr)
65 * code_ptr is 4 instructions after MOVW/MOVT used to address
68 jte = mono_jumptable_get_entry (code_ptr - 16);
69 g_assert ( jte != NULL);
74 mono_arch_patch_callsite (guint8 *method_start, guint8 *code_ptr, guint8 *addr)
76 guint32 *code = (guint32*)code_ptr;
78 /* This is the 'bl' or the 'mov pc' instruction */
82 * Note that methods are called also with the bl opcode.
84 if ((((*code) >> 25) & 7) == 5) {
85 /*g_print ("direct patching\n");*/
86 arm_patch ((guint8*)code, addr);
87 mono_arch_flush_icache ((guint8*)code, 4);
91 if ((((*code) >> 20) & 0xFF) == 0x12) {
92 /*g_print ("patching bx\n");*/
93 arm_patch ((guint8*)code, addr);
94 mono_arch_flush_icache ((guint8*)(code - 2), 4);
98 g_assert_not_reached ();
103 mono_arch_patch_plt_entry (guint8 *code, gpointer *got, mgreg_t *regs, guint8 *addr)
107 /* Patch the jump table entry used by the plt entry */
108 if (*(guint32*)code == 0xe59fc000) {
109 /* ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0); */
110 guint32 offset = ((guint32*)code)[2];
112 jump_entry = code + offset + 12;
113 } else if (*(guint16*)(code - 4) == 0xf8df) {
115 * Thumb PLT entry, begins with ldr.w ip, [pc, #8], code points to entry + 4, see
116 * mono_arm_get_thumb_plt_entry ().
121 offset = *(guint32*)(code + 12);
122 jump_entry = code + offset + 8;
124 g_assert_not_reached ();
127 *(guint8**)jump_entry = addr;
131 mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
133 mono_arch_patch_callsite (NULL, code, mini_get_nullified_class_init_trampoline ());
138 #define arm_is_imm12(v) ((int)(v) > -4096 && (int)(v) < 4096)
140 #ifndef USE_JUMP_TABLES
142 * Return the instruction to jump from code to target, 0 if not
143 * reachable with a single instruction
146 branch_for_target_reachable (guint8 *branch, guint8 *target)
148 gint diff = target - branch - 8;
149 g_assert ((diff & 3) == 0);
151 if (diff <= 33554431)
152 return (ARMCOND_AL << ARMCOND_SHIFT) | (ARM_BR_TAG) | (diff >> 2);
154 /* diff between 0 and -33554432 */
155 if (diff >= -33554432)
156 return (ARMCOND_AL << ARMCOND_SHIFT) | (ARM_BR_TAG) | ((diff >> 2) & ~0xff000000);
162 static inline guint8*
163 emit_bx (guint8* code, int reg)
165 if (mono_arm_thumb_supported ())
168 ARM_MOV_REG_REG (code, ARMREG_PC, reg);
172 /* Stack size for trampoline function
174 #define STACK ALIGN_TO (sizeof (MonoLMF), 8)
176 /* Method-specific trampoline code fragment size */
177 #define METHOD_TRAMPOLINE_SIZE 64
179 /* Jump-specific trampoline code fragment size */
180 #define JUMP_TRAMPOLINE_SIZE 64
183 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
186 guint8 *buf, *code = NULL;
187 #ifdef USE_JUMP_TABLES
188 gpointer *load_get_lmf_addr = NULL, *load_trampoline = NULL;
190 guint8 *load_get_lmf_addr = NULL, *load_trampoline = NULL;
194 int cfa_offset, regsave_size, lr_offset;
195 GSList *unwind_ops = NULL;
196 MonoJumpInfo *ji = NULL;
199 #ifdef USE_JUMP_TABLES
203 /* Now we'll create in 'buf' the ARM trampoline code. This
204 is the trampoline code common to all methods */
208 /* Add space for saving/restoring VFP regs. */
209 if (mono_arm_is_hard_float ())
212 code = buf = mono_global_codeman_reserve (buf_len);
215 * At this point lr points to the specific arg and sp points to the saved
216 * regs on the stack (all but PC and SP). The original LR value has been
217 * saved as sp + LR_OFFSET by the push in the specific trampoline
220 /* The size of the area already allocated by the push in the specific trampoline */
221 regsave_size = 14 * sizeof (mgreg_t);
222 /* The offset where lr was saved inside the regsave area */
223 lr_offset = 13 * sizeof (mgreg_t);
225 // FIXME: Finish the unwind info, the current info allows us to unwind
226 // when the trampoline is not in the epilog
228 // CFA = SP + (num registers pushed) * 4
229 cfa_offset = 14 * sizeof (mgreg_t);
230 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, ARMREG_SP, cfa_offset);
231 // PC saved at sp+LR_OFFSET
232 mono_add_unwind_op_offset (unwind_ops, code, buf, ARMREG_LR, -4);
234 if (aot && tramp_type != MONO_TRAMPOLINE_GENERIC_CLASS_INIT) {
236 * For page trampolines the data is in r1, so just move it, otherwise use the got slot as below.
237 * The trampoline contains a pc-relative offset to the got slot
238 * preceeding the got slot where the value is stored. The offset can be
242 ARM_MOV_REG_REG (code, ARMREG_V2, ARMREG_R1);
244 ARM_LDR_IMM (code, ARMREG_V2, ARMREG_LR, 0);
245 ARM_ADD_REG_IMM (code, ARMREG_V2, ARMREG_V2, 4, 0);
246 ARM_LDR_REG_REG (code, ARMREG_V2, ARMREG_V2, ARMREG_LR);
249 if (tramp_type != MONO_TRAMPOLINE_GENERIC_CLASS_INIT) {
250 ARM_LDR_IMM (code, ARMREG_V2, ARMREG_LR, 0);
253 ARM_MOV_REG_REG (code, ARMREG_V2, MONO_ARCH_VTABLE_REG);
255 ARM_LDR_IMM (code, ARMREG_V3, ARMREG_SP, lr_offset);
257 /* ok, now we can continue with the MonoLMF setup, mostly untouched
258 * from emit_prolog in mini-arm.c
259 * This is a synthetized call to mono_get_lmf_addr ()
262 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_get_lmf_addr");
263 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
265 *(gpointer*)code = NULL;
267 ARM_LDR_REG_REG (code, ARMREG_R0, ARMREG_PC, ARMREG_R0);
269 #ifdef USE_JUMP_TABLES
270 load_get_lmf_addr = mono_jumptable_add_entry ();
271 code = mono_arm_load_jumptable_entry (code, load_get_lmf_addr, ARMREG_R0);
273 load_get_lmf_addr = code;
277 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
278 code = emit_bx (code, ARMREG_R0);
280 /* we build the MonoLMF structure on the stack - see mini-arm.h
281 * The pointer to the struct is put in r1.
282 * the iregs array is already allocated on the stack by push.
284 code = mono_arm_emit_load_imm (code, ARMREG_R2, STACK - regsave_size);
285 ARM_SUB_REG_REG (code, ARMREG_SP, ARMREG_SP, ARMREG_R2);
286 cfa_offset += STACK - regsave_size;
287 mono_add_unwind_op_def_cfa_offset (unwind_ops, code, buf, cfa_offset);
289 code = mono_arm_emit_load_imm (code, ARMREG_R2, STACK - sizeof (MonoLMF));
290 ARM_ADD_REG_REG (code, ARMREG_V1, ARMREG_SP, ARMREG_R2);
293 * The stack now looks like:
295 * v1 -> <rest of LMF>
299 /* r0 is the result from mono_get_lmf_addr () */
300 ARM_STR_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, lmf_addr));
301 /* new_lmf->previous_lmf = *lmf_addr */
302 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_R0, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
303 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
304 /* *(lmf_addr) = r1 */
305 ARM_STR_IMM (code, ARMREG_V1, ARMREG_R0, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
306 /* save method info (it's in v2) */
307 if ((tramp_type == MONO_TRAMPOLINE_JIT) || (tramp_type == MONO_TRAMPOLINE_JUMP))
308 ARM_STR_IMM (code, ARMREG_V2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, method));
310 ARM_MOV_REG_IMM8 (code, ARMREG_R2, 0);
311 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, method));
314 code = mono_arm_emit_load_imm (code, ARMREG_R2, cfa_offset);
315 ARM_ADD_REG_REG (code, ARMREG_R2, ARMREG_SP, ARMREG_R2);
316 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, sp));
318 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_V1, (MONO_STRUCT_OFFSET (MonoLMF, iregs) + ARMREG_FP*4));
319 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fp));
320 /* save the IP (caller ip) */
321 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
322 ARM_MOV_REG_IMM8 (code, ARMREG_R2, 0);
324 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_V1, (MONO_STRUCT_OFFSET (MonoLMF, iregs) + 13*4));
326 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, ip));
328 /* Save VFP registers. */
329 if (mono_arm_is_hard_float ()) {
331 * Strictly speaking, we don't have to save d0-d7 in the LMF, but
332 * it's easier than attempting to store them on the stack since
333 * this trampoline code is pretty messy.
335 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fregs));
336 ARM_FSTMD (code, ARM_VFP_D0, 8, ARMREG_R0);
340 * Now we're ready to call xxx_trampoline ().
342 /* Arg 1: the saved registers */
343 ARM_ADD_REG_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, iregs), 0);
345 /* Arg 2: code (next address to the instruction that called us) */
346 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
347 ARM_MOV_REG_IMM8 (code, ARMREG_R1, 0);
349 ARM_MOV_REG_REG (code, ARMREG_R1, ARMREG_V3);
352 /* Arg 3: the specific argument, stored in v2
354 ARM_MOV_REG_REG (code, ARMREG_R2, ARMREG_V2);
357 char *icall_name = g_strdup_printf ("trampoline_func_%d", tramp_type);
358 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, icall_name);
359 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
361 *(gpointer*)code = NULL;
363 ARM_LDR_REG_REG (code, ARMREG_IP, ARMREG_PC, ARMREG_IP);
365 #ifdef USE_JUMP_TABLES
366 load_trampoline = mono_jumptable_add_entry ();
367 code = mono_arm_load_jumptable_entry (code, load_trampoline, ARMREG_IP);
369 load_trampoline = code;
374 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
375 code = emit_bx (code, ARMREG_IP);
377 /* OK, code address is now on r0. Move it to the place on the stack
378 * where IP was saved (it is now no more useful to us and it can be
379 * clobbered). This way we can just restore all the regs in one inst
382 ARM_STR_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, iregs) + (ARMREG_R12 * sizeof (mgreg_t)));
384 /* Check for thread interruption */
385 /* This is not perf critical code so no need to check the interrupt flag */
387 * Have to call the _force_ variant, since there could be a protected wrapper on the top of the stack.
390 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_thread_force_interruption_checkpoint");
391 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
393 *(gpointer*)code = NULL;
395 ARM_LDR_REG_REG (code, ARMREG_IP, ARMREG_PC, ARMREG_IP);
397 #ifdef USE_JUMP_TABLES
398 gpointer *jte = mono_jumptable_add_entry ();
399 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
400 jte [0] = mono_thread_force_interruption_checkpoint;
402 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
404 *(gpointer*)code = mono_thread_force_interruption_checkpoint;
408 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
409 code = emit_bx (code, ARMREG_IP);
412 * Now we restore the MonoLMF (see emit_epilogue in mini-arm.c)
413 * and the rest of the registers, so the method called will see
414 * the same state as before we executed.
416 /* ip = previous_lmf */
417 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
419 ARM_LDR_IMM (code, ARMREG_LR, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, lmf_addr));
420 /* *(lmf_addr) = previous_lmf */
421 ARM_STR_IMM (code, ARMREG_IP, ARMREG_LR, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
423 /* Restore VFP registers. */
424 if (mono_arm_is_hard_float ()) {
425 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fregs));
426 ARM_FLDMD (code, ARM_VFP_D0, 8, ARMREG_R0);
429 /* Non-standard function epilogue. Instead of doing a proper
430 * return, we just jump to the compiled code.
432 /* Restore the registers and jump to the code:
433 * Note that IP has been conveniently set to the method addr.
435 ARM_ADD_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, STACK - regsave_size);
436 ARM_POP_NWB (code, 0x5fff);
437 if (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH)
438 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_IP);
439 ARM_ADD_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, regsave_size);
440 if ((tramp_type == MONO_TRAMPOLINE_CLASS_INIT) || (tramp_type == MONO_TRAMPOLINE_GENERIC_CLASS_INIT) || (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH))
441 code = emit_bx (code, ARMREG_LR);
443 code = emit_bx (code, ARMREG_IP);
445 #ifdef USE_JUMP_TABLES
446 load_get_lmf_addr [0] = mono_get_lmf_addr;
447 load_trampoline [0] = (gpointer)mono_get_trampoline_func (tramp_type);
449 constants = (gpointer*)code;
450 constants [0] = mono_get_lmf_addr;
451 constants [1] = (gpointer)mono_get_trampoline_func (tramp_type);
454 /* backpatch by emitting the missing instructions skipped above */
455 ARM_LDR_IMM (load_get_lmf_addr, ARMREG_R0, ARMREG_PC, (code - load_get_lmf_addr - 8));
456 ARM_LDR_IMM (load_trampoline, ARMREG_IP, ARMREG_PC, (code + 4 - load_trampoline - 8));
462 /* Flush instruction cache, since we've generated code */
463 mono_arch_flush_icache (buf, code - buf);
466 g_assert ((code - buf) <= buf_len);
469 tramp_name = mono_get_generic_trampoline_name (tramp_type);
470 *info = mono_tramp_info_create (tramp_name, buf, code - buf, ji, unwind_ops);
478 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
482 code = buf = mono_global_codeman_reserve (16);
484 code = emit_bx (code, ARMREG_LR);
486 mono_arch_flush_icache (buf, code - buf);
489 *info = mono_tramp_info_create ("nullified_class_init_trampoline", buf, code - buf, NULL, NULL);
494 #define SPEC_TRAMP_SIZE 24
497 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
499 guint8 *code, *buf, *tramp;
501 #ifndef USE_JUMP_TABLES
502 guint32 short_branch;
504 guint32 size = SPEC_TRAMP_SIZE;
506 tramp = mono_get_trampoline_code (tramp_type);
509 mono_domain_lock (domain);
510 #ifdef USE_JUMP_TABLES
511 code = buf = mono_domain_code_reserve_align (domain, size, 4);
513 code = buf = mono_domain_code_reserve_align (domain, size, 4);
514 if ((short_branch = branch_for_target_reachable (code + 4, tramp))) {
516 mono_domain_code_commit (domain, code, SPEC_TRAMP_SIZE, size);
519 mono_domain_unlock (domain);
521 code = buf = mono_global_codeman_reserve (size);
524 #ifdef USE_JUMP_TABLES
525 /* For jumptables case we always generate the same code for trampolines,
527 * push {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, lr}
533 ARM_PUSH (code, 0x5fff);
534 constants = mono_jumptable_add_entries (2);
535 code = mono_arm_load_jumptable_entry_addr (code, constants, ARMREG_LR);
536 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_LR, 4);
537 code = emit_bx (code, ARMREG_R1);
538 constants [0] = arg1;
539 constants [1] = tramp;
541 /* we could reduce this to 12 bytes if tramp is within reach:
545 * The called code can access method using the lr register
546 * A 20 byte sequence could be:
548 * ARM_MOV_REG_REG (lr, pc)
549 * ARM_LDR_IMM (pc, pc, 0)
553 /* We save all the registers, except PC and SP */
554 ARM_PUSH (code, 0x5fff);
556 constants = (gpointer*)code;
557 constants [0] = GUINT_TO_POINTER (short_branch | (1 << 24));
558 constants [1] = arg1;
561 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 8); /* temp reg */
562 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
563 code = emit_bx (code, ARMREG_R1);
565 constants = (gpointer*)code;
566 constants [0] = arg1;
567 constants [1] = tramp;
572 /* Flush instruction cache, since we've generated code */
573 mono_arch_flush_icache (buf, code - buf);
575 g_assert ((code - buf) <= size);
578 *code_len = code - buf;
584 * mono_arch_get_unbox_trampoline:
586 * @addr: pointer to native code for @m
588 * when value type methods are called through the vtable we need to unbox the
589 * this argument. This method returns a pointer to a trampoline which does
590 * unboxing before calling the method
593 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
595 guint8 *code, *start;
596 MonoDomain *domain = mono_domain_get ();
597 #ifdef USE_JUMP_TABLES
604 start = code = mono_domain_code_reserve (domain, size);
606 #ifdef USE_JUMP_TABLES
607 jte = mono_jumptable_add_entry ();
608 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
609 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_R0, sizeof (MonoObject));
610 code = emit_bx (code, ARMREG_IP);
613 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 4);
614 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_R0, sizeof (MonoObject));
615 code = emit_bx (code, ARMREG_IP);
616 *(guint32*)code = (guint32)addr;
619 mono_arch_flush_icache (start, code - start);
620 g_assert ((code - start) <= size);
621 /*g_print ("unbox trampoline at %d for %s:%s\n", this_pos, m->klass->name, m->name);
622 g_print ("unbox code is at %p for method at %p\n", start, addr);*/
628 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
630 guint8 *code, *start;
631 #ifdef USE_JUMP_TABLES
637 MonoDomain *domain = mono_domain_get ();
639 start = code = mono_domain_code_reserve (domain, buf_len);
641 #ifdef USE_JUMP_TABLES
642 jte = mono_jumptable_add_entries (2);
643 code = mono_arm_load_jumptable_entry_addr (code, jte, ARMREG_IP);
644 ARM_LDR_IMM (code, MONO_ARCH_RGCTX_REG, ARMREG_IP, 0);
645 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_IP, 4);
646 ARM_BX (code, ARMREG_IP);
650 ARM_LDR_IMM (code, MONO_ARCH_RGCTX_REG, ARMREG_PC, 0);
651 ARM_LDR_IMM (code, ARMREG_PC, ARMREG_PC, 0);
652 *(guint32*)code = (guint32)mrgctx;
654 *(guint32*)code = (guint32)addr;
658 g_assert ((code - start) <= buf_len);
660 mono_arch_flush_icache (start, code - start);
666 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
672 guint8 **rgctx_null_jumps;
676 MonoJumpInfo *ji = NULL;
677 GSList *unwind_ops = NULL;
678 #ifdef USE_JUMP_TABLES
682 mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
683 index = MONO_RGCTX_SLOT_INDEX (slot);
685 index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
686 for (depth = 0; ; ++depth) {
687 int size = mono_class_rgctx_get_array_size (depth, mrgctx);
689 if (index < size - 1)
694 tramp_size = 64 + 16 * depth;
696 code = buf = mono_global_codeman_reserve (tramp_size);
698 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, ARMREG_SP, 0);
700 rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
703 /* The vtable/mrgctx is in R0 */
704 g_assert (MONO_ARCH_VTABLE_REG == ARMREG_R0);
708 ARM_MOV_REG_REG (code, ARMREG_R1, ARMREG_R0);
710 /* load rgctx ptr from vtable */
711 g_assert (arm_is_imm12 (MONO_STRUCT_OFFSET (MonoVTable, runtime_generic_context)));
712 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R0, MONO_STRUCT_OFFSET (MonoVTable, runtime_generic_context));
713 /* is the rgctx ptr null? */
714 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
715 /* if yes, jump to actual trampoline */
716 rgctx_null_jumps [njumps ++] = code;
717 ARM_B_COND (code, ARMCOND_EQ, 0);
720 for (i = 0; i < depth; ++i) {
721 /* load ptr to next array */
722 if (mrgctx && i == 0) {
723 g_assert (arm_is_imm12 (MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT));
724 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R1, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT);
726 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R1, 0);
728 /* is the ptr null? */
729 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
730 /* if yes, jump to actual trampoline */
731 rgctx_null_jumps [njumps ++] = code;
732 ARM_B_COND (code, ARMCOND_EQ, 0);
736 code = mono_arm_emit_load_imm (code, ARMREG_R2, sizeof (gpointer) * (index + 1));
737 ARM_LDR_REG_REG (code, ARMREG_R1, ARMREG_R1, ARMREG_R2);
738 /* is the slot null? */
739 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
740 /* if yes, jump to actual trampoline */
741 rgctx_null_jumps [njumps ++] = code;
742 ARM_B_COND (code, ARMCOND_EQ, 0);
743 /* otherwise return, result is in R1 */
744 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_R1);
745 code = emit_bx (code, ARMREG_LR);
747 g_assert (njumps <= depth + 2);
748 for (i = 0; i < njumps; ++i)
749 arm_patch (rgctx_null_jumps [i], code);
751 g_free (rgctx_null_jumps);
755 /* The vtable/mrgctx is still in R0 */
758 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
759 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0);
761 *(gpointer*)code = NULL;
763 ARM_LDR_REG_REG (code, ARMREG_PC, ARMREG_PC, ARMREG_R1);
765 tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), &code_len);
767 /* Jump to the actual trampoline */
768 #ifdef USE_JUMP_TABLES
769 jte = mono_jumptable_add_entry ();
771 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_R1);
772 code = emit_bx (code, ARMREG_R1);
774 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0); /* temp reg */
775 code = emit_bx (code, ARMREG_R1);
776 *(gpointer*)code = tramp;
781 mono_arch_flush_icache (buf, code - buf);
783 g_assert (code - buf <= tramp_size);
786 char *name = mono_get_rgctx_fetch_trampoline_name (slot);
787 *info = mono_tramp_info_create (name, buf, code - buf, ji, unwind_ops);
795 mono_arch_create_general_rgctx_lazy_fetch_trampoline (MonoTrampInfo **info, gboolean aot)
799 MonoJumpInfo *ji = NULL;
800 GSList *unwind_ops = NULL;
806 code = buf = mono_global_codeman_reserve (tramp_size);
808 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, ARMREG_SP, 0);
810 // FIXME: Currently, we always go to the slow path.
811 /* Load trampoline addr */
812 ARM_LDR_IMM (code, ARMREG_R1, MONO_ARCH_RGCTX_REG, 4);
813 /* The vtable/mrgctx is in R0 */
814 g_assert (MONO_ARCH_VTABLE_REG == ARMREG_R0);
815 code = emit_bx (code, ARMREG_R1);
817 mono_arch_flush_icache (buf, code - buf);
819 g_assert (code - buf <= tramp_size);
822 *info = mono_tramp_info_create ("rgctx_fetch_trampoline_general", buf, code - buf, ji, unwind_ops);
827 #define arm_is_imm8(v) ((v) > -256 && (v) < 256)
830 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
834 static int byte_offset = -1;
835 static guint8 bitmask;
838 guint32 code_len, imm8;
840 GSList *unwind_ops = NULL;
841 MonoJumpInfo *ji = NULL;
845 code = buf = mono_global_codeman_reserve (tramp_size);
848 mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
850 g_assert (arm_is_imm8 (byte_offset));
851 ARM_LDRSB_IMM (code, ARMREG_IP, MONO_ARCH_VTABLE_REG, byte_offset);
852 imm8 = mono_arm_is_rotated_imm8 (bitmask, &rot_amount);
853 g_assert (imm8 >= 0);
854 ARM_AND_REG_IMM (code, ARMREG_IP, ARMREG_IP, imm8, rot_amount);
855 ARM_CMP_REG_IMM (code, ARMREG_IP, 0, 0);
857 ARM_B_COND (code, ARMCOND_EQ, 0);
859 /* Initialized case */
860 ARM_MOV_REG_REG (code, ARMREG_PC, ARMREG_LR);
862 /* Uninitialized case */
863 arm_patch (jump, code);
866 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "specific_trampoline_generic_class_init");
867 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0);
869 *(gpointer*)code = NULL;
871 ARM_LDR_REG_REG (code, ARMREG_PC, ARMREG_PC, ARMREG_R1);
873 #ifdef USE_JUMP_TABLES
874 gpointer *jte = mono_jumptable_add_entry ();
876 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_GENERIC_CLASS_INIT, mono_get_root_domain (), &code_len);
878 /* Jump to the actual trampoline */
879 #ifdef USE_JUMP_TABLES
880 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_R1);
882 code = emit_bx (code, ARMREG_R1);
884 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0); /* temp reg */
885 code = emit_bx (code, ARMREG_R1);
886 *(gpointer*)code = tramp;
891 mono_arch_flush_icache (buf, code - buf);
893 g_assert (code - buf <= tramp_size);
896 *info = mono_tramp_info_create ("generic_class_init_trampoline", buf, code - buf, ji, unwind_ops);
902 handler_block_trampoline_helper (gpointer *ptr)
904 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
905 return jit_tls->handler_block_return_address;
909 mono_arch_create_handler_block_trampoline (MonoTrampInfo **info, gboolean aot)
914 MonoJumpInfo *ji = NULL;
915 GSList *unwind_ops = NULL;
919 code = buf = mono_global_codeman_reserve (tramp_size);
921 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_HANDLER_BLOCK_GUARD, NULL, NULL);
924 This trampoline restore the call chain of the handler block then jumps into the code that deals with it.
928 * We are in a method frame after the call emitted by OP_CALL_HANDLER.
930 /* Obtain jit_tls->handler_block_return_address */
931 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
933 *(gpointer*)code = handler_block_trampoline_helper;
936 /* Set it as the return address so the trampoline will return to it */
937 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_R0);
939 /* Call the trampoline */
940 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
941 code = emit_bx (code, ARMREG_R0);
942 *(gpointer*)code = tramp;
945 mono_arch_flush_icache (buf, code - buf);
946 g_assert (code - buf <= tramp_size);
949 *info = mono_tramp_info_create ("handler_block_trampoline", buf, code - buf, ji, unwind_ops);
957 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
959 g_assert_not_reached ();
964 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
966 g_assert_not_reached ();
971 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
973 g_assert_not_reached ();
978 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
980 g_assert_not_reached ();
985 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
987 g_assert_not_reached ();
992 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
994 g_assert_not_reached ();
999 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
1001 g_assert_not_reached ();
1006 mono_arch_create_handler_block_trampoline (MonoTrampInfo **info, gboolean aot)
1008 g_assert_not_reached ();
1012 #endif /* DISABLE_JIT */
1015 mono_arch_get_call_target (guint8 *code)
1017 guint32 ins = ((guint32*)(gpointer)code) [-1];
1020 /* Should be a 'bl' or a 'b' */
1021 if (((ins >> 25) & 0x7) == 0x5) {
1023 /* Should be a 'bl' */
1024 if ((((ins >> 25) & 0x7) == 0x5) && (((ins >> 24) & 0x1) == 0x1)) {
1026 gint32 disp = ((gint32)ins) & 0xffffff;
1027 guint8 *target = code - 4 + 8 + (disp * 4);
1036 mono_arch_get_plt_info_offset (guint8 *plt_entry, mgreg_t *regs, guint8 *code)
1038 /* The offset is stored as the 4th word of the plt entry */
1039 return ((guint32*)plt_entry) [3];
1043 * Return the address of the PLT entry called by the thumb code CODE.
1046 mono_arm_get_thumb_plt_entry (guint8 *code)
1048 int s, j1, j2, imm10, imm11, i1, i2, imm32;
1053 /* code should be right after a BL */
1054 code = (guint8*)((mgreg_t)code & ~1);
1055 base = (guint8*)((mgreg_t)code & ~3);
1057 t1 = ((guint16*)bl) [0];
1058 t2 = ((guint16*)bl) [1];
1060 g_assert ((t1 >> 11) == 0x1e);
1062 s = (t1 >> 10) & 0x1;
1063 imm10 = (t1 >> 0) & 0x3ff;
1064 j1 = (t2 >> 13) & 0x1;
1065 j2 = (t2 >> 11) & 0x1;
1068 i1 = (s ^ j1) ? 0 : 1;
1069 i2 = (s ^ j2) ? 0 : 1;
1071 imm32 = (imm11 << 1) | (imm10 << 12) | (i2 << 22) | (i1 << 23);
1075 target = code + imm32;
1077 /* target now points to the thumb plt entry */
1078 /* ldr.w r12, [pc, #8] */
1079 g_assert (((guint16*)target) [0] == 0xf8df);
1080 g_assert (((guint16*)target) [1] == 0xc008);
1083 * The PLT info offset is at offset 16, but mono_arch_get_plt_entry_offset () returns
1084 * the 3rd word, so compensate by returning a different value.
1094 * mono_arch_get_gsharedvt_arg_trampoline:
1096 * See tramp-x86.c for documentation.
1099 mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
1101 guint8 *code, *start;
1103 gpointer *constants;
1107 start = code = mono_domain_code_reserve (domain, buf_len);
1109 /* Similar to the specialized trampoline code */
1110 ARM_PUSH (code, (1 << ARMREG_R0) | (1 << ARMREG_R1) | (1 << ARMREG_R2) | (1 << ARMREG_R3) | (1 << ARMREG_LR));
1111 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 8);
1112 /* arg is passed in LR */
1113 ARM_LDR_IMM (code, ARMREG_LR, ARMREG_PC, 0);
1114 code = emit_bx (code, ARMREG_IP);
1115 constants = (gpointer*)code;
1116 constants [0] = arg;
1117 constants [1] = addr;
1120 g_assert ((code - start) <= buf_len);
1122 nacl_domain_code_validate (domain, &start, buf_len, &code);
1123 mono_arch_flush_icache (start, code - start);
1131 mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
1133 g_assert_not_reached ();
1139 #if defined(ENABLE_GSHAREDVT)
1141 #include "../../../mono-extensions/mono/mini/tramp-arm-gsharedvt.c"
1146 mono_arm_start_gsharedvt_call (GSharedVtCallInfo *info, gpointer *caller, gpointer *callee, gpointer mrgctx_reg)
1148 g_assert_not_reached ();
1153 mono_arch_get_gsharedvt_trampoline (MonoTrampInfo **info, gboolean aot)
1160 #endif /* !MONOTOUCH */