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/metadata/profiler-private.h>
20 #include <mono/arch/arm/arm-codegen.h>
21 #include <mono/arch/arm/arm-vfp-codegen.h>
25 #include "debugger-agent.h"
27 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
29 #ifdef USE_JUMP_TABLES
32 decode_imm16 (guint32 insn)
34 return (((insn >> 16) & 0xf) << 12) | (insn & 0xfff);
37 #define INSN_MASK 0xff00000
38 #define MOVW_MASK ((3 << 24) | (0 << 20))
39 #define MOVT_MASK ((3 << 24) | (4 << 20))
42 mono_arch_jumptable_entry_from_code (guint8 *code)
44 guint32 insn1 = ((guint32*)code) [0];
45 guint32 insn2 = ((guint32*)code) [1];
47 if (((insn1 & INSN_MASK) == MOVW_MASK) &&
48 ((insn2 & INSN_MASK) == MOVT_MASK) ) {
49 guint32 imm_lo = decode_imm16 (insn1);
50 guint32 imm_hi = decode_imm16 (insn2);
51 return (gpointer*) GUINT_TO_POINTER (imm_lo | (imm_hi << 16));
53 g_assert_not_reached ();
63 mono_arch_patch_callsite (guint8 *method_start, guint8 *code_ptr, guint8 *addr)
67 * code_ptr is 4 instructions after MOVW/MOVT used to address
70 jte = mono_jumptable_get_entry (code_ptr - 16);
71 g_assert ( jte != NULL);
76 mono_arch_patch_callsite (guint8 *method_start, guint8 *code_ptr, guint8 *addr)
78 guint32 *code = (guint32*)code_ptr;
80 /* This is the 'bl' or the 'mov pc' instruction */
84 * Note that methods are called also with the bl opcode.
86 if ((((*code) >> 25) & 7) == 5) {
87 /*g_print ("direct patching\n");*/
88 arm_patch ((guint8*)code, addr);
89 mono_arch_flush_icache ((guint8*)code, 4);
93 if ((((*code) >> 20) & 0xFF) == 0x12) {
94 /*g_print ("patching bx\n");*/
95 arm_patch ((guint8*)code, addr);
96 mono_arch_flush_icache ((guint8*)(code - 2), 4);
100 g_assert_not_reached ();
105 mono_arch_patch_plt_entry (guint8 *code, gpointer *got, mgreg_t *regs, guint8 *addr)
109 /* Patch the jump table entry used by the plt entry */
110 if (*(guint32*)code == 0xe59fc000) {
111 /* ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0); */
112 guint32 offset = ((guint32*)code)[2];
114 jump_entry = code + offset + 12;
115 } else if (*(guint16*)(code - 4) == 0xf8df) {
117 * Thumb PLT entry, begins with ldr.w ip, [pc, #8], code points to entry + 4, see
118 * mono_arm_get_thumb_plt_entry ().
123 offset = *(guint32*)(code + 12);
124 jump_entry = code + offset + 8;
126 g_assert_not_reached ();
129 *(guint8**)jump_entry = addr;
133 mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
135 mono_arch_patch_callsite (NULL, code, mini_get_nullified_class_init_trampoline ());
140 #define arm_is_imm12(v) ((int)(v) > -4096 && (int)(v) < 4096)
142 #ifndef USE_JUMP_TABLES
144 * Return the instruction to jump from code to target, 0 if not
145 * reachable with a single instruction
148 branch_for_target_reachable (guint8 *branch, guint8 *target)
150 gint diff = target - branch - 8;
151 g_assert ((diff & 3) == 0);
153 if (diff <= 33554431)
154 return (ARMCOND_AL << ARMCOND_SHIFT) | (ARM_BR_TAG) | (diff >> 2);
156 /* diff between 0 and -33554432 */
157 if (diff >= -33554432)
158 return (ARMCOND_AL << ARMCOND_SHIFT) | (ARM_BR_TAG) | ((diff >> 2) & ~0xff000000);
164 static inline guint8*
165 emit_bx (guint8* code, int reg)
167 if (mono_arm_thumb_supported ())
170 ARM_MOV_REG_REG (code, ARMREG_PC, reg);
174 /* Stack size for trampoline function
176 #define STACK ALIGN_TO (sizeof (MonoLMF), 8)
178 /* Method-specific trampoline code fragment size */
179 #define METHOD_TRAMPOLINE_SIZE 64
181 /* Jump-specific trampoline code fragment size */
182 #define JUMP_TRAMPOLINE_SIZE 64
185 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
188 guint8 *buf, *code = NULL;
189 #ifdef USE_JUMP_TABLES
190 gpointer *load_get_lmf_addr = NULL, *load_trampoline = NULL;
192 guint8 *load_get_lmf_addr = NULL, *load_trampoline = NULL;
196 int cfa_offset, regsave_size, lr_offset;
197 GSList *unwind_ops = NULL;
198 MonoJumpInfo *ji = NULL;
201 #ifdef USE_JUMP_TABLES
205 /* Now we'll create in 'buf' the ARM trampoline code. This
206 is the trampoline code common to all methods */
210 /* Add space for saving/restoring VFP regs. */
211 if (mono_arm_is_hard_float ())
214 code = buf = mono_global_codeman_reserve (buf_len);
217 * At this point lr points to the specific arg and sp points to the saved
218 * regs on the stack (all but PC and SP). The original LR value has been
219 * saved as sp + LR_OFFSET by the push in the specific trampoline
222 /* The size of the area already allocated by the push in the specific trampoline */
223 regsave_size = 14 * sizeof (mgreg_t);
224 /* The offset where lr was saved inside the regsave area */
225 lr_offset = 13 * sizeof (mgreg_t);
227 // FIXME: Finish the unwind info, the current info allows us to unwind
228 // when the trampoline is not in the epilog
230 // CFA = SP + (num registers pushed) * 4
231 cfa_offset = 14 * sizeof (mgreg_t);
232 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, ARMREG_SP, cfa_offset);
233 // PC saved at sp+LR_OFFSET
234 mono_add_unwind_op_offset (unwind_ops, code, buf, ARMREG_LR, -4);
236 if (aot && tramp_type != MONO_TRAMPOLINE_GENERIC_CLASS_INIT) {
238 * For page trampolines the data is in r1, so just move it, otherwise use the got slot as below.
239 * The trampoline contains a pc-relative offset to the got slot
240 * preceeding the got slot where the value is stored. The offset can be
244 ARM_MOV_REG_REG (code, ARMREG_V2, ARMREG_R1);
246 ARM_LDR_IMM (code, ARMREG_V2, ARMREG_LR, 0);
247 ARM_ADD_REG_IMM (code, ARMREG_V2, ARMREG_V2, 4, 0);
248 ARM_LDR_REG_REG (code, ARMREG_V2, ARMREG_V2, ARMREG_LR);
251 if (tramp_type != MONO_TRAMPOLINE_GENERIC_CLASS_INIT) {
252 ARM_LDR_IMM (code, ARMREG_V2, ARMREG_LR, 0);
255 ARM_MOV_REG_REG (code, ARMREG_V2, MONO_ARCH_VTABLE_REG);
257 ARM_LDR_IMM (code, ARMREG_V3, ARMREG_SP, lr_offset);
259 /* ok, now we can continue with the MonoLMF setup, mostly untouched
260 * from emit_prolog in mini-arm.c
261 * This is a synthetized call to mono_get_lmf_addr ()
264 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_get_lmf_addr");
265 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
267 *(gpointer*)code = NULL;
269 ARM_LDR_REG_REG (code, ARMREG_R0, ARMREG_PC, ARMREG_R0);
271 #ifdef USE_JUMP_TABLES
272 load_get_lmf_addr = mono_jumptable_add_entry ();
273 code = mono_arm_load_jumptable_entry (code, load_get_lmf_addr, ARMREG_R0);
275 load_get_lmf_addr = code;
279 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
280 code = emit_bx (code, ARMREG_R0);
282 /* we build the MonoLMF structure on the stack - see mini-arm.h
283 * The pointer to the struct is put in r1.
284 * the iregs array is already allocated on the stack by push.
286 code = mono_arm_emit_load_imm (code, ARMREG_R2, STACK - regsave_size);
287 ARM_SUB_REG_REG (code, ARMREG_SP, ARMREG_SP, ARMREG_R2);
288 cfa_offset += STACK - regsave_size;
289 mono_add_unwind_op_def_cfa_offset (unwind_ops, code, buf, cfa_offset);
291 code = mono_arm_emit_load_imm (code, ARMREG_R2, STACK - sizeof (MonoLMF));
292 ARM_ADD_REG_REG (code, ARMREG_V1, ARMREG_SP, ARMREG_R2);
295 * The stack now looks like:
297 * v1 -> <rest of LMF>
301 /* r0 is the result from mono_get_lmf_addr () */
302 ARM_STR_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, lmf_addr));
303 /* new_lmf->previous_lmf = *lmf_addr */
304 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_R0, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
305 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
306 /* *(lmf_addr) = r1 */
307 ARM_STR_IMM (code, ARMREG_V1, ARMREG_R0, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
308 /* save method info (it's in v2) */
309 if ((tramp_type == MONO_TRAMPOLINE_JIT) || (tramp_type == MONO_TRAMPOLINE_JUMP))
310 ARM_STR_IMM (code, ARMREG_V2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, method));
312 ARM_MOV_REG_IMM8 (code, ARMREG_R2, 0);
313 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, method));
316 code = mono_arm_emit_load_imm (code, ARMREG_R2, cfa_offset);
317 ARM_ADD_REG_REG (code, ARMREG_R2, ARMREG_SP, ARMREG_R2);
318 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, sp));
320 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_V1, (MONO_STRUCT_OFFSET (MonoLMF, iregs) + ARMREG_FP*4));
321 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fp));
322 /* save the IP (caller ip) */
323 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
324 ARM_MOV_REG_IMM8 (code, ARMREG_R2, 0);
326 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_V1, (MONO_STRUCT_OFFSET (MonoLMF, iregs) + 13*4));
328 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, ip));
330 /* Save VFP registers. */
331 if (mono_arm_is_hard_float ()) {
333 * Strictly speaking, we don't have to save d0-d7 in the LMF, but
334 * it's easier than attempting to store them on the stack since
335 * this trampoline code is pretty messy.
337 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fregs));
338 ARM_FSTMD (code, ARM_VFP_D0, 8, ARMREG_R0);
342 * Now we're ready to call xxx_trampoline ().
344 /* Arg 1: the saved registers */
345 ARM_ADD_REG_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, iregs), 0);
347 /* Arg 2: code (next address to the instruction that called us) */
348 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
349 ARM_MOV_REG_IMM8 (code, ARMREG_R1, 0);
351 ARM_MOV_REG_REG (code, ARMREG_R1, ARMREG_V3);
354 /* Arg 3: the specific argument, stored in v2
356 ARM_MOV_REG_REG (code, ARMREG_R2, ARMREG_V2);
359 char *icall_name = g_strdup_printf ("trampoline_func_%d", tramp_type);
360 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, icall_name);
361 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
363 *(gpointer*)code = NULL;
365 ARM_LDR_REG_REG (code, ARMREG_IP, ARMREG_PC, ARMREG_IP);
367 #ifdef USE_JUMP_TABLES
368 load_trampoline = mono_jumptable_add_entry ();
369 code = mono_arm_load_jumptable_entry (code, load_trampoline, ARMREG_IP);
371 load_trampoline = code;
376 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
377 code = emit_bx (code, ARMREG_IP);
379 /* OK, code address is now on r0. Move it to the place on the stack
380 * where IP was saved (it is now no more useful to us and it can be
381 * clobbered). This way we can just restore all the regs in one inst
384 ARM_STR_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, iregs) + (ARMREG_R12 * sizeof (mgreg_t)));
386 /* Check for thread interruption */
387 /* This is not perf critical code so no need to check the interrupt flag */
389 * Have to call the _force_ variant, since there could be a protected wrapper on the top of the stack.
392 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_thread_force_interruption_checkpoint");
393 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
395 *(gpointer*)code = NULL;
397 ARM_LDR_REG_REG (code, ARMREG_IP, ARMREG_PC, ARMREG_IP);
399 #ifdef USE_JUMP_TABLES
400 gpointer *jte = mono_jumptable_add_entry ();
401 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
402 jte [0] = mono_thread_force_interruption_checkpoint;
404 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
406 *(gpointer*)code = mono_thread_force_interruption_checkpoint;
410 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
411 code = emit_bx (code, ARMREG_IP);
414 * Now we restore the MonoLMF (see emit_epilogue in mini-arm.c)
415 * and the rest of the registers, so the method called will see
416 * the same state as before we executed.
418 /* ip = previous_lmf */
419 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
421 ARM_LDR_IMM (code, ARMREG_LR, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, lmf_addr));
422 /* *(lmf_addr) = previous_lmf */
423 ARM_STR_IMM (code, ARMREG_IP, ARMREG_LR, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
425 /* Restore VFP registers. */
426 if (mono_arm_is_hard_float ()) {
427 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fregs));
428 ARM_FLDMD (code, ARM_VFP_D0, 8, ARMREG_R0);
431 /* Non-standard function epilogue. Instead of doing a proper
432 * return, we just jump to the compiled code.
434 /* Restore the registers and jump to the code:
435 * Note that IP has been conveniently set to the method addr.
437 ARM_ADD_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, STACK - regsave_size);
438 ARM_POP_NWB (code, 0x5fff);
439 if (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH)
440 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_IP);
441 ARM_ADD_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, regsave_size);
442 if ((tramp_type == MONO_TRAMPOLINE_CLASS_INIT) || (tramp_type == MONO_TRAMPOLINE_GENERIC_CLASS_INIT) || (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH))
443 code = emit_bx (code, ARMREG_LR);
445 code = emit_bx (code, ARMREG_IP);
447 #ifdef USE_JUMP_TABLES
448 load_get_lmf_addr [0] = mono_get_lmf_addr;
449 load_trampoline [0] = (gpointer)mono_get_trampoline_func (tramp_type);
451 constants = (gpointer*)code;
452 constants [0] = mono_get_lmf_addr;
453 constants [1] = (gpointer)mono_get_trampoline_func (tramp_type);
456 /* backpatch by emitting the missing instructions skipped above */
457 ARM_LDR_IMM (load_get_lmf_addr, ARMREG_R0, ARMREG_PC, (code - load_get_lmf_addr - 8));
458 ARM_LDR_IMM (load_trampoline, ARMREG_IP, ARMREG_PC, (code + 4 - load_trampoline - 8));
464 /* Flush instruction cache, since we've generated code */
465 mono_arch_flush_icache (buf, code - buf);
466 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
469 g_assert ((code - buf) <= buf_len);
472 tramp_name = mono_get_generic_trampoline_name (tramp_type);
473 *info = mono_tramp_info_create (tramp_name, buf, code - buf, ji, unwind_ops);
480 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
484 code = buf = mono_global_codeman_reserve (16);
486 code = emit_bx (code, ARMREG_LR);
488 mono_arch_flush_icache (buf, code - buf);
489 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
491 *info = mono_tramp_info_create ("nullified_class_init_trampoline", buf, code - buf, NULL, NULL);
496 #define SPEC_TRAMP_SIZE 24
499 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
501 guint8 *code, *buf, *tramp;
503 #ifndef USE_JUMP_TABLES
504 guint32 short_branch = FALSE;
506 guint32 size = SPEC_TRAMP_SIZE;
508 tramp = mono_get_trampoline_code (tramp_type);
511 mono_domain_lock (domain);
512 #ifdef USE_JUMP_TABLES
513 code = buf = mono_domain_code_reserve_align (domain, size, 4);
515 code = buf = mono_domain_code_reserve_align (domain, size, 4);
516 if ((short_branch = branch_for_target_reachable (code + 4, tramp))) {
518 mono_domain_code_commit (domain, code, SPEC_TRAMP_SIZE, size);
521 mono_domain_unlock (domain);
523 code = buf = mono_global_codeman_reserve (size);
524 short_branch = FALSE;
527 #ifdef USE_JUMP_TABLES
528 /* For jumptables case we always generate the same code for trampolines,
530 * push {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, lr}
536 ARM_PUSH (code, 0x5fff);
537 constants = mono_jumptable_add_entries (2);
538 code = mono_arm_load_jumptable_entry_addr (code, constants, ARMREG_LR);
539 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_LR, 4);
540 code = emit_bx (code, ARMREG_R1);
541 constants [0] = arg1;
542 constants [1] = tramp;
544 /* we could reduce this to 12 bytes if tramp is within reach:
548 * The called code can access method using the lr register
549 * A 20 byte sequence could be:
551 * ARM_MOV_REG_REG (lr, pc)
552 * ARM_LDR_IMM (pc, pc, 0)
556 /* We save all the registers, except PC and SP */
557 ARM_PUSH (code, 0x5fff);
559 constants = (gpointer*)code;
560 constants [0] = GUINT_TO_POINTER (short_branch | (1 << 24));
561 constants [1] = arg1;
564 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 8); /* temp reg */
565 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
566 code = emit_bx (code, ARMREG_R1);
568 constants = (gpointer*)code;
569 constants [0] = arg1;
570 constants [1] = tramp;
575 /* Flush instruction cache, since we've generated code */
576 mono_arch_flush_icache (buf, code - buf);
577 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_SPECIFIC_TRAMPOLINE, mono_get_generic_trampoline_simple_name (tramp_type));
579 g_assert ((code - buf) <= size);
582 *code_len = code - buf;
588 * mono_arch_get_unbox_trampoline:
590 * @addr: pointer to native code for @m
592 * when value type methods are called through the vtable we need to unbox the
593 * this argument. This method returns a pointer to a trampoline which does
594 * unboxing before calling the method
597 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
599 guint8 *code, *start;
600 MonoDomain *domain = mono_domain_get ();
601 #ifdef USE_JUMP_TABLES
608 start = code = mono_domain_code_reserve (domain, size);
610 #ifdef USE_JUMP_TABLES
611 jte = mono_jumptable_add_entry ();
612 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
613 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_R0, sizeof (MonoObject));
614 code = emit_bx (code, ARMREG_IP);
617 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 4);
618 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_R0, sizeof (MonoObject));
619 code = emit_bx (code, ARMREG_IP);
620 *(guint32*)code = (guint32)addr;
623 mono_arch_flush_icache (start, code - start);
624 mono_profiler_code_buffer_new (start, code - start, MONO_PROFILER_CODE_BUFFER_UNBOX_TRAMPOLINE, m);
625 g_assert ((code - start) <= size);
626 /*g_print ("unbox trampoline at %d for %s:%s\n", this_pos, m->klass->name, m->name);
627 g_print ("unbox code is at %p for method at %p\n", start, addr);*/
633 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
635 guint8 *code, *start;
636 #ifdef USE_JUMP_TABLES
642 MonoDomain *domain = mono_domain_get ();
644 start = code = mono_domain_code_reserve (domain, buf_len);
646 #ifdef USE_JUMP_TABLES
647 jte = mono_jumptable_add_entries (2);
648 code = mono_arm_load_jumptable_entry_addr (code, jte, ARMREG_IP);
649 ARM_LDR_IMM (code, MONO_ARCH_RGCTX_REG, ARMREG_IP, 0);
650 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_IP, 4);
651 ARM_BX (code, ARMREG_IP);
655 ARM_LDR_IMM (code, MONO_ARCH_RGCTX_REG, ARMREG_PC, 0);
656 ARM_LDR_IMM (code, ARMREG_PC, ARMREG_PC, 0);
657 *(guint32*)code = (guint32)mrgctx;
659 *(guint32*)code = (guint32)addr;
663 g_assert ((code - start) <= buf_len);
665 mono_arch_flush_icache (start, code - start);
666 mono_profiler_code_buffer_new (start, code - start, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
672 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
678 guint8 **rgctx_null_jumps;
682 MonoJumpInfo *ji = NULL;
683 GSList *unwind_ops = NULL;
684 #ifdef USE_JUMP_TABLES
688 mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
689 index = MONO_RGCTX_SLOT_INDEX (slot);
691 index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
692 for (depth = 0; ; ++depth) {
693 int size = mono_class_rgctx_get_array_size (depth, mrgctx);
695 if (index < size - 1)
700 tramp_size = 64 + 16 * depth;
702 code = buf = mono_global_codeman_reserve (tramp_size);
704 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, ARMREG_SP, 0);
706 rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
709 /* The vtable/mrgctx is in R0 */
710 g_assert (MONO_ARCH_VTABLE_REG == ARMREG_R0);
714 ARM_MOV_REG_REG (code, ARMREG_R1, ARMREG_R0);
716 /* load rgctx ptr from vtable */
717 g_assert (arm_is_imm12 (MONO_STRUCT_OFFSET (MonoVTable, runtime_generic_context)));
718 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R0, MONO_STRUCT_OFFSET (MonoVTable, runtime_generic_context));
719 /* is the rgctx ptr null? */
720 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
721 /* if yes, jump to actual trampoline */
722 rgctx_null_jumps [njumps ++] = code;
723 ARM_B_COND (code, ARMCOND_EQ, 0);
726 for (i = 0; i < depth; ++i) {
727 /* load ptr to next array */
728 if (mrgctx && i == 0) {
729 g_assert (arm_is_imm12 (MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT));
730 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R1, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT);
732 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R1, 0);
734 /* is the ptr null? */
735 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
736 /* if yes, jump to actual trampoline */
737 rgctx_null_jumps [njumps ++] = code;
738 ARM_B_COND (code, ARMCOND_EQ, 0);
742 code = mono_arm_emit_load_imm (code, ARMREG_R2, sizeof (gpointer) * (index + 1));
743 ARM_LDR_REG_REG (code, ARMREG_R1, ARMREG_R1, ARMREG_R2);
744 /* is the slot null? */
745 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
746 /* if yes, jump to actual trampoline */
747 rgctx_null_jumps [njumps ++] = code;
748 ARM_B_COND (code, ARMCOND_EQ, 0);
749 /* otherwise return, result is in R1 */
750 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_R1);
751 code = emit_bx (code, ARMREG_LR);
753 g_assert (njumps <= depth + 2);
754 for (i = 0; i < njumps; ++i)
755 arm_patch (rgctx_null_jumps [i], code);
757 g_free (rgctx_null_jumps);
761 /* The vtable/mrgctx is still in R0 */
764 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
765 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0);
767 *(gpointer*)code = NULL;
769 ARM_LDR_REG_REG (code, ARMREG_PC, ARMREG_PC, ARMREG_R1);
771 tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), &code_len);
773 /* Jump to the actual trampoline */
774 #ifdef USE_JUMP_TABLES
775 jte = mono_jumptable_add_entry ();
777 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_R1);
778 code = emit_bx (code, ARMREG_R1);
780 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0); /* temp reg */
781 code = emit_bx (code, ARMREG_R1);
782 *(gpointer*)code = tramp;
787 mono_arch_flush_icache (buf, code - buf);
788 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
790 g_assert (code - buf <= tramp_size);
792 char *name = mono_get_rgctx_fetch_trampoline_name (slot);
793 *info = mono_tramp_info_create (name, buf, code - buf, ji, unwind_ops);
800 mono_arch_create_general_rgctx_lazy_fetch_trampoline (MonoTrampInfo **info, gboolean aot)
804 MonoJumpInfo *ji = NULL;
805 GSList *unwind_ops = NULL;
811 code = buf = mono_global_codeman_reserve (tramp_size);
813 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, ARMREG_SP, 0);
815 // FIXME: Currently, we always go to the slow path.
816 /* Load trampoline addr */
817 ARM_LDR_IMM (code, ARMREG_R1, MONO_ARCH_RGCTX_REG, 4);
818 /* The vtable/mrgctx is in R0 */
819 g_assert (MONO_ARCH_VTABLE_REG == ARMREG_R0);
820 code = emit_bx (code, ARMREG_R1);
822 mono_arch_flush_icache (buf, code - buf);
823 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
825 g_assert (code - buf <= tramp_size);
827 *info = mono_tramp_info_create ("rgctx_fetch_trampoline_general", buf, code - buf, ji, unwind_ops);
832 #define arm_is_imm8(v) ((v) > -256 && (v) < 256)
835 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
839 static int byte_offset = -1;
840 static guint8 bitmask;
843 guint32 code_len, imm8;
845 GSList *unwind_ops = NULL;
846 MonoJumpInfo *ji = NULL;
850 code = buf = mono_global_codeman_reserve (tramp_size);
853 mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
855 g_assert (arm_is_imm8 (byte_offset));
856 ARM_LDRSB_IMM (code, ARMREG_IP, MONO_ARCH_VTABLE_REG, byte_offset);
857 imm8 = mono_arm_is_rotated_imm8 (bitmask, &rot_amount);
858 g_assert (imm8 >= 0);
859 ARM_AND_REG_IMM (code, ARMREG_IP, ARMREG_IP, imm8, rot_amount);
860 ARM_CMP_REG_IMM (code, ARMREG_IP, 0, 0);
862 ARM_B_COND (code, ARMCOND_EQ, 0);
864 /* Initialized case */
865 ARM_MOV_REG_REG (code, ARMREG_PC, ARMREG_LR);
867 /* Uninitialized case */
868 arm_patch (jump, code);
871 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "specific_trampoline_generic_class_init");
872 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0);
874 *(gpointer*)code = NULL;
876 ARM_LDR_REG_REG (code, ARMREG_PC, ARMREG_PC, ARMREG_R1);
878 #ifdef USE_JUMP_TABLES
879 gpointer *jte = mono_jumptable_add_entry ();
881 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_GENERIC_CLASS_INIT, mono_get_root_domain (), &code_len);
883 /* Jump to the actual trampoline */
884 #ifdef USE_JUMP_TABLES
885 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_R1);
887 code = emit_bx (code, ARMREG_R1);
889 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0); /* temp reg */
890 code = emit_bx (code, ARMREG_R1);
891 *(gpointer*)code = tramp;
896 mono_arch_flush_icache (buf, code - buf);
897 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
899 g_assert (code - buf <= tramp_size);
901 *info = mono_tramp_info_create ("generic_class_init_trampoline", buf, code - buf, ji, unwind_ops);
907 handler_block_trampoline_helper (gpointer *ptr)
909 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
910 return jit_tls->handler_block_return_address;
914 mono_arch_create_handler_block_trampoline (MonoTrampInfo **info, gboolean aot)
919 MonoJumpInfo *ji = NULL;
920 GSList *unwind_ops = NULL;
924 code = buf = mono_global_codeman_reserve (tramp_size);
926 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_HANDLER_BLOCK_GUARD, NULL, NULL);
929 This trampoline restore the call chain of the handler block then jumps into the code that deals with it.
933 * We are in a method frame after the call emitted by OP_CALL_HANDLER.
935 /* Obtain jit_tls->handler_block_return_address */
936 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
938 *(gpointer*)code = handler_block_trampoline_helper;
941 /* Set it as the return address so the trampoline will return to it */
942 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_R0);
944 /* Call the trampoline */
945 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
946 code = emit_bx (code, ARMREG_R0);
947 *(gpointer*)code = tramp;
950 mono_arch_flush_icache (buf, code - buf);
951 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
952 g_assert (code - buf <= tramp_size);
954 *info = mono_tramp_info_create ("handler_block_trampoline", buf, code - buf, ji, unwind_ops);
960 mono_arch_create_sdb_trampoline (gboolean single_step, MonoTrampInfo **info, gboolean aot)
963 GSList *unwind_ops = NULL;
964 MonoJumpInfo *ji = NULL;
967 buf = code = mono_global_codeman_reserve (96);
970 * Construct the MonoContext structure on the stack.
973 frame_size = sizeof (MonoContext);
974 frame_size = ALIGN_TO (frame_size, MONO_ARCH_FRAME_ALIGNMENT);
975 ARM_SUB_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, frame_size);
977 /* save ip, lr and pc into their correspodings ctx.regs slots. */
978 ARM_STR_IMM (code, ARMREG_IP, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs) + sizeof (mgreg_t) * ARMREG_IP);
979 ARM_STR_IMM (code, ARMREG_LR, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_LR);
980 ARM_STR_IMM (code, ARMREG_LR, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_PC);
982 /* save r0..r10 and fp */
983 ARM_ADD_REG_IMM8 (code, ARMREG_IP, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs));
984 ARM_STM (code, ARMREG_IP, 0x0fff);
986 /* now we can update fp. */
987 ARM_MOV_REG_REG (code, ARMREG_FP, ARMREG_SP);
989 /* make ctx.esp hold the actual value of sp at the beginning of this method. */
990 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_FP, frame_size);
991 ARM_STR_IMM (code, ARMREG_R0, ARMREG_IP, 4 * ARMREG_SP);
992 ARM_STR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_SP);
994 /* make ctx.eip hold the address of the call. */
995 ARM_SUB_REG_IMM8 (code, ARMREG_LR, ARMREG_LR, 4);
996 ARM_STR_IMM (code, ARMREG_LR, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, pc));
998 /* r0 now points to the MonoContext */
999 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_FP);
1003 #ifdef USE_JUMP_TABLES
1005 gpointer *jte = mono_jumptable_add_entry ();
1006 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
1010 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
1013 *(gpointer*)code = debugger_agent_single_step_from_context;
1015 *(gpointer*)code = debugger_agent_breakpoint_from_context;
1018 ARM_BLX_REG (code, ARMREG_IP);
1020 /* we're back; save ctx.eip and ctx.esp into the corresponding regs slots. */
1021 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, pc));
1022 ARM_STR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_LR);
1023 ARM_STR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_PC);
1025 /* make ip point to the regs array, then restore everything, including pc. */
1026 ARM_ADD_REG_IMM8 (code, ARMREG_IP, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs));
1027 ARM_LDM (code, ARMREG_IP, 0xffff);
1029 mono_arch_flush_icache (buf, code - buf);
1030 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
1032 const char *tramp_name = single_step ? "sdb_single_step_trampoline" : "sdb_breakpoint_trampoline";
1033 *info = mono_tramp_info_create (tramp_name, buf, code - buf, ji, unwind_ops);
1041 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
1043 g_assert_not_reached ();
1048 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
1050 g_assert_not_reached ();
1055 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
1057 g_assert_not_reached ();
1062 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
1064 g_assert_not_reached ();
1069 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
1071 g_assert_not_reached ();
1076 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
1078 g_assert_not_reached ();
1083 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
1085 g_assert_not_reached ();
1090 mono_arch_create_handler_block_trampoline (MonoTrampInfo **info, gboolean aot)
1092 g_assert_not_reached ();
1097 mono_arch_create_sdb_trampoline (gboolean single_step, MonoTrampInfo **info, gboolean aot)
1099 g_assert_not_reached ();
1103 #endif /* DISABLE_JIT */
1106 mono_arch_get_call_target (guint8 *code)
1108 guint32 ins = ((guint32*)(gpointer)code) [-1];
1111 /* Should be a 'bl' or a 'b' */
1112 if (((ins >> 25) & 0x7) == 0x5) {
1114 /* Should be a 'bl' */
1115 if ((((ins >> 25) & 0x7) == 0x5) && (((ins >> 24) & 0x1) == 0x1)) {
1117 gint32 disp = ((((gint32)ins) & 0xffffff) << 8) >> 8;
1118 guint8 *target = code - 4 + 8 + (disp * 4);
1127 mono_arch_get_plt_info_offset (guint8 *plt_entry, mgreg_t *regs, guint8 *code)
1129 /* The offset is stored as the 4th word of the plt entry */
1130 return ((guint32*)plt_entry) [3];
1134 * Return the address of the PLT entry called by the thumb code CODE.
1137 mono_arm_get_thumb_plt_entry (guint8 *code)
1139 int s, j1, j2, imm10, imm11, i1, i2, imm32;
1144 /* code should be right after a BL */
1145 code = (guint8*)((mgreg_t)code & ~1);
1146 base = (guint8*)((mgreg_t)code & ~3);
1148 t1 = ((guint16*)bl) [0];
1149 t2 = ((guint16*)bl) [1];
1151 g_assert ((t1 >> 11) == 0x1e);
1153 s = (t1 >> 10) & 0x1;
1154 imm10 = (t1 >> 0) & 0x3ff;
1155 j1 = (t2 >> 13) & 0x1;
1156 j2 = (t2 >> 11) & 0x1;
1159 i1 = (s ^ j1) ? 0 : 1;
1160 i2 = (s ^ j2) ? 0 : 1;
1162 imm32 = (imm11 << 1) | (imm10 << 12) | (i2 << 22) | (i1 << 23);
1164 /* Sign extend from 24 bits to 32 bits */
1165 imm32 = ((gint32)imm32 << 8) >> 8;
1167 target = code + imm32;
1169 /* target now points to the thumb plt entry */
1170 /* ldr.w r12, [pc, #8] */
1171 g_assert (((guint16*)target) [0] == 0xf8df);
1172 g_assert (((guint16*)target) [1] == 0xc008);
1175 * The PLT info offset is at offset 16, but mono_arch_get_plt_entry_offset () returns
1176 * the 3rd word, so compensate by returning a different value.
1186 * mono_arch_get_gsharedvt_arg_trampoline:
1188 * See tramp-x86.c for documentation.
1191 mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
1195 gpointer *constants;
1199 buf = code = mono_domain_code_reserve (domain, buf_len);
1201 /* Similar to the specialized trampoline code */
1202 ARM_PUSH (code, (1 << ARMREG_R0) | (1 << ARMREG_R1) | (1 << ARMREG_R2) | (1 << ARMREG_R3) | (1 << ARMREG_LR));
1203 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 8);
1204 /* arg is passed in LR */
1205 ARM_LDR_IMM (code, ARMREG_LR, ARMREG_PC, 0);
1206 code = emit_bx (code, ARMREG_IP);
1207 constants = (gpointer*)code;
1208 constants [0] = arg;
1209 constants [1] = addr;
1212 g_assert ((code - buf) <= buf_len);
1214 nacl_domain_code_validate (domain, &buf, buf_len, &code);
1215 mono_arch_flush_icache (buf, code - buf);
1216 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
1224 mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
1226 g_assert_not_reached ();
1232 #if defined(ENABLE_GSHAREDVT)
1234 #include "../../../mono-extensions/mono/mini/tramp-arm-gsharedvt.c"
1239 mono_arm_start_gsharedvt_call (GSharedVtCallInfo *info, gpointer *caller, gpointer *callee, gpointer mrgctx_reg)
1241 g_assert_not_reached ();
1246 mono_arch_get_gsharedvt_trampoline (MonoTrampInfo **info, gboolean aot)
1252 #endif /* !MONOTOUCH */