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;
134 #define arm_is_imm12(v) ((int)(v) > -4096 && (int)(v) < 4096)
136 #ifndef USE_JUMP_TABLES
138 * Return the instruction to jump from code to target, 0 if not
139 * reachable with a single instruction
142 branch_for_target_reachable (guint8 *branch, guint8 *target)
144 gint diff = target - branch - 8;
145 g_assert ((diff & 3) == 0);
147 if (diff <= 33554431)
148 return (ARMCOND_AL << ARMCOND_SHIFT) | (ARM_BR_TAG) | (diff >> 2);
150 /* diff between 0 and -33554432 */
151 if (diff >= -33554432)
152 return (ARMCOND_AL << ARMCOND_SHIFT) | (ARM_BR_TAG) | ((diff >> 2) & ~0xff000000);
158 static inline guint8*
159 emit_bx (guint8* code, int reg)
161 if (mono_arm_thumb_supported ())
164 ARM_MOV_REG_REG (code, ARMREG_PC, reg);
168 /* Stack size for trampoline function
170 #define STACK ALIGN_TO (sizeof (MonoLMF), MONO_ARCH_FRAME_ALIGNMENT)
172 /* Method-specific trampoline code fragment size */
173 #define METHOD_TRAMPOLINE_SIZE 64
175 /* Jump-specific trampoline code fragment size */
176 #define JUMP_TRAMPOLINE_SIZE 64
179 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
182 guint8 *buf, *code = NULL;
183 #ifdef USE_JUMP_TABLES
184 gpointer *load_get_lmf_addr = NULL, *load_trampoline = NULL;
186 guint8 *load_get_lmf_addr = NULL, *load_trampoline = NULL;
190 int cfa_offset, regsave_size, lr_offset;
191 GSList *unwind_ops = NULL;
192 MonoJumpInfo *ji = NULL;
195 #ifdef USE_JUMP_TABLES
199 /* Now we'll create in 'buf' the ARM trampoline code. This
200 is the trampoline code common to all methods */
204 /* Add space for saving/restoring VFP regs. */
205 if (mono_arm_is_hard_float ())
208 code = buf = mono_global_codeman_reserve (buf_len);
211 * At this point lr points to the specific arg and sp points to the saved
212 * regs on the stack (all but PC and SP). The original LR value has been
213 * saved as sp + LR_OFFSET by the push in the specific trampoline
216 /* The size of the area already allocated by the push in the specific trampoline */
217 regsave_size = 14 * sizeof (mgreg_t);
218 /* The offset where lr was saved inside the regsave area */
219 lr_offset = 13 * sizeof (mgreg_t);
221 // CFA = SP + (num registers pushed) * 4
222 cfa_offset = 14 * sizeof (mgreg_t);
223 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, ARMREG_SP, cfa_offset);
224 // PC saved at sp+LR_OFFSET
225 mono_add_unwind_op_offset (unwind_ops, code, buf, ARMREG_LR, -4);
229 * For page trampolines the data is in r1, so just move it, otherwise use the got slot as below.
230 * The trampoline contains a pc-relative offset to the got slot
231 * preceeding the got slot where the value is stored. The offset can be
234 /* See if emit_trampolines () in aot-compiler.c for the '2' */
236 ARM_MOV_REG_REG (code, ARMREG_V2, ARMREG_R1);
238 ARM_LDR_IMM (code, ARMREG_V2, ARMREG_LR, 0);
239 ARM_ADD_REG_IMM (code, ARMREG_V2, ARMREG_V2, 4, 0);
240 ARM_LDR_REG_REG (code, ARMREG_V2, ARMREG_V2, ARMREG_LR);
243 ARM_LDR_IMM (code, ARMREG_V2, ARMREG_LR, 0);
245 ARM_LDR_IMM (code, ARMREG_V3, ARMREG_SP, lr_offset);
247 /* we build the MonoLMF structure on the stack - see mini-arm.h
248 * The pointer to the struct is put in r1.
249 * the iregs array is already allocated on the stack by push.
251 code = mono_arm_emit_load_imm (code, ARMREG_R2, STACK - regsave_size);
252 ARM_SUB_REG_REG (code, ARMREG_SP, ARMREG_SP, ARMREG_R2);
253 cfa_offset += STACK - regsave_size;
254 mono_add_unwind_op_def_cfa_offset (unwind_ops, code, buf, cfa_offset);
256 code = mono_arm_emit_load_imm (code, ARMREG_R2, STACK - sizeof (MonoLMF));
257 ARM_ADD_REG_REG (code, ARMREG_V1, ARMREG_SP, ARMREG_R2);
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);
283 * The stack now looks like:
285 * v1 -> <rest of LMF>
289 /* r0 is the result from mono_get_lmf_addr () */
290 ARM_STR_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, lmf_addr));
291 /* new_lmf->previous_lmf = *lmf_addr */
292 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_R0, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
293 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
294 /* *(lmf_addr) = r1 */
295 ARM_STR_IMM (code, ARMREG_V1, ARMREG_R0, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
296 /* save method info (it's in v2) */
297 if ((tramp_type == MONO_TRAMPOLINE_JIT) || (tramp_type == MONO_TRAMPOLINE_JUMP))
298 ARM_STR_IMM (code, ARMREG_V2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, method));
300 ARM_MOV_REG_IMM8 (code, ARMREG_R2, 0);
301 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, method));
304 code = mono_arm_emit_load_imm (code, ARMREG_R2, cfa_offset);
305 ARM_ADD_REG_REG (code, ARMREG_R2, ARMREG_SP, ARMREG_R2);
306 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, sp));
308 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_V1, (MONO_STRUCT_OFFSET (MonoLMF, iregs) + ARMREG_FP*4));
309 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fp));
310 /* save the IP (caller ip) */
311 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
312 ARM_MOV_REG_IMM8 (code, ARMREG_R2, 0);
314 ARM_LDR_IMM (code, ARMREG_R2, ARMREG_V1, (MONO_STRUCT_OFFSET (MonoLMF, iregs) + 13*4));
316 ARM_STR_IMM (code, ARMREG_R2, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, ip));
318 /* Save VFP registers. */
319 if (mono_arm_is_hard_float ()) {
321 * Strictly speaking, we don't have to save d0-d7 in the LMF, but
322 * it's easier than attempting to store them on the stack since
323 * this trampoline code is pretty messy.
325 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fregs));
326 ARM_FSTMD (code, ARM_VFP_D0, 8, ARMREG_R0);
330 * Now we're ready to call xxx_trampoline ().
332 /* Arg 1: the saved registers */
333 ARM_ADD_REG_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, iregs), 0);
335 /* Arg 2: code (next address to the instruction that called us) */
336 if (tramp_type == MONO_TRAMPOLINE_JUMP) {
337 ARM_MOV_REG_IMM8 (code, ARMREG_R1, 0);
339 ARM_MOV_REG_REG (code, ARMREG_R1, ARMREG_V3);
342 /* Arg 3: the specific argument, stored in v2
344 ARM_MOV_REG_REG (code, ARMREG_R2, ARMREG_V2);
347 char *icall_name = g_strdup_printf ("trampoline_func_%d", tramp_type);
348 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, icall_name);
349 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
351 *(gpointer*)code = NULL;
353 ARM_LDR_REG_REG (code, ARMREG_IP, ARMREG_PC, ARMREG_IP);
355 #ifdef USE_JUMP_TABLES
356 load_trampoline = mono_jumptable_add_entry ();
357 code = mono_arm_load_jumptable_entry (code, load_trampoline, ARMREG_IP);
359 load_trampoline = code;
364 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
365 code = emit_bx (code, ARMREG_IP);
367 /* OK, code address is now on r0. Move it to the place on the stack
368 * where IP was saved (it is now no more useful to us and it can be
369 * clobbered). This way we can just restore all the regs in one inst
372 ARM_STR_IMM (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, iregs) + (ARMREG_R12 * sizeof (mgreg_t)));
374 /* Check for thread interruption */
375 /* This is not perf critical code so no need to check the interrupt flag */
377 * Have to call the _force_ variant, since there could be a protected wrapper on the top of the stack.
380 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_thread_force_interruption_checkpoint");
381 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
383 *(gpointer*)code = NULL;
385 ARM_LDR_REG_REG (code, ARMREG_IP, ARMREG_PC, ARMREG_IP);
387 #ifdef USE_JUMP_TABLES
388 gpointer *jte = mono_jumptable_add_entry ();
389 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
390 jte [0] = mono_thread_force_interruption_checkpoint;
392 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
394 *(gpointer*)code = mono_thread_force_interruption_checkpoint;
398 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
399 code = emit_bx (code, ARMREG_IP);
402 * Now we restore the MonoLMF (see emit_epilogue in mini-arm.c)
403 * and the rest of the registers, so the method called will see
404 * the same state as before we executed.
406 /* ip = previous_lmf */
407 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
409 ARM_LDR_IMM (code, ARMREG_LR, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, lmf_addr));
410 /* *(lmf_addr) = previous_lmf */
411 ARM_STR_IMM (code, ARMREG_IP, ARMREG_LR, MONO_STRUCT_OFFSET (MonoLMF, previous_lmf));
413 /* Restore VFP registers. */
414 if (mono_arm_is_hard_float ()) {
415 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_V1, MONO_STRUCT_OFFSET (MonoLMF, fregs));
416 ARM_FLDMD (code, ARM_VFP_D0, 8, ARMREG_R0);
419 /* Non-standard function epilogue. Instead of doing a proper
420 * return, we just jump to the compiled code.
422 /* Restore the registers and jump to the code:
423 * Note that IP has been conveniently set to the method addr.
425 ARM_ADD_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, STACK - regsave_size);
426 cfa_offset -= STACK - regsave_size;
427 mono_add_unwind_op_def_cfa_offset (unwind_ops, code, buf, cfa_offset);
428 ARM_POP_NWB (code, 0x5fff);
429 mono_add_unwind_op_same_value (unwind_ops, code, buf, ARMREG_LR);
430 if (tramp_type == MONO_TRAMPOLINE_RGCTX_LAZY_FETCH)
431 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_IP);
432 ARM_ADD_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, regsave_size);
433 cfa_offset -= regsave_size;
434 g_assert (cfa_offset == 0);
435 mono_add_unwind_op_def_cfa_offset (unwind_ops, code, buf, cfa_offset);
436 if (MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type))
437 code = emit_bx (code, ARMREG_LR);
439 code = emit_bx (code, ARMREG_IP);
441 #ifdef USE_JUMP_TABLES
442 load_get_lmf_addr [0] = mono_get_lmf_addr;
443 load_trampoline [0] = (gpointer)mono_get_trampoline_func (tramp_type);
445 constants = (gpointer*)code;
446 constants [0] = mono_get_lmf_addr;
447 constants [1] = (gpointer)mono_get_trampoline_func (tramp_type);
450 /* backpatch by emitting the missing instructions skipped above */
451 ARM_LDR_IMM (load_get_lmf_addr, ARMREG_R0, ARMREG_PC, (code - load_get_lmf_addr - 8));
452 ARM_LDR_IMM (load_trampoline, ARMREG_IP, ARMREG_PC, (code + 4 - load_trampoline - 8));
458 /* Flush instruction cache, since we've generated code */
459 mono_arch_flush_icache (buf, code - buf);
460 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
463 g_assert ((code - buf) <= buf_len);
466 tramp_name = mono_get_generic_trampoline_name (tramp_type);
467 *info = mono_tramp_info_create (tramp_name, buf, code - buf, ji, unwind_ops);
473 #define SPEC_TRAMP_SIZE 24
476 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
478 guint8 *code, *buf, *tramp;
480 #ifndef USE_JUMP_TABLES
481 guint32 short_branch = FALSE;
483 guint32 size = SPEC_TRAMP_SIZE;
485 tramp = mono_get_trampoline_code (tramp_type);
488 mono_domain_lock (domain);
489 #ifdef USE_JUMP_TABLES
490 code = buf = mono_domain_code_reserve_align (domain, size, 4);
492 code = buf = mono_domain_code_reserve_align (domain, size, 4);
493 if ((short_branch = branch_for_target_reachable (code + 4, tramp))) {
495 mono_domain_code_commit (domain, code, SPEC_TRAMP_SIZE, size);
498 mono_domain_unlock (domain);
500 code = buf = mono_global_codeman_reserve (size);
501 short_branch = FALSE;
504 #ifdef USE_JUMP_TABLES
505 /* For jumptables case we always generate the same code for trampolines,
507 * push {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, lr}
513 ARM_PUSH (code, 0x5fff);
514 constants = mono_jumptable_add_entries (2);
515 code = mono_arm_load_jumptable_entry_addr (code, constants, ARMREG_LR);
516 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_LR, 4);
517 code = emit_bx (code, ARMREG_R1);
518 constants [0] = arg1;
519 constants [1] = tramp;
521 /* we could reduce this to 12 bytes if tramp is within reach:
525 * The called code can access method using the lr register
526 * A 20 byte sequence could be:
528 * ARM_MOV_REG_REG (lr, pc)
529 * ARM_LDR_IMM (pc, pc, 0)
533 /* We save all the registers, except PC and SP */
534 ARM_PUSH (code, 0x5fff);
536 constants = (gpointer*)code;
537 constants [0] = GUINT_TO_POINTER (short_branch | (1 << 24));
538 constants [1] = arg1;
541 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 8); /* temp reg */
542 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_PC);
543 code = emit_bx (code, ARMREG_R1);
545 constants = (gpointer*)code;
546 constants [0] = arg1;
547 constants [1] = tramp;
552 /* Flush instruction cache, since we've generated code */
553 mono_arch_flush_icache (buf, code - buf);
554 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_SPECIFIC_TRAMPOLINE, mono_get_generic_trampoline_simple_name (tramp_type));
556 g_assert ((code - buf) <= size);
559 *code_len = code - buf;
565 * mono_arch_get_unbox_trampoline:
567 * @addr: pointer to native code for @m
569 * when value type methods are called through the vtable we need to unbox the
570 * this argument. This method returns a pointer to a trampoline which does
571 * unboxing before calling the method
574 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
576 guint8 *code, *start;
577 MonoDomain *domain = mono_domain_get ();
579 #ifdef USE_JUMP_TABLES
586 start = code = mono_domain_code_reserve (domain, size);
588 unwind_ops = mono_arch_get_cie_program ();
590 #ifdef USE_JUMP_TABLES
591 jte = mono_jumptable_add_entry ();
592 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
593 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_R0, sizeof (MonoObject));
594 code = emit_bx (code, ARMREG_IP);
597 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 4);
598 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_R0, sizeof (MonoObject));
599 code = emit_bx (code, ARMREG_IP);
600 *(guint32*)code = (guint32)addr;
603 mono_arch_flush_icache (start, code - start);
604 mono_profiler_code_buffer_new (start, code - start, MONO_PROFILER_CODE_BUFFER_UNBOX_TRAMPOLINE, m);
605 g_assert ((code - start) <= size);
606 /*g_print ("unbox trampoline at %d for %s:%s\n", this_pos, m->klass->name, m->name);
607 g_print ("unbox code is at %p for method at %p\n", start, addr);*/
609 mono_tramp_info_register (mono_tramp_info_create (NULL, start, code - start, NULL, unwind_ops), domain);
615 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
617 guint8 *code, *start;
619 #ifdef USE_JUMP_TABLES
625 MonoDomain *domain = mono_domain_get ();
627 start = code = mono_domain_code_reserve (domain, buf_len);
629 unwind_ops = mono_arch_get_cie_program ();
631 #ifdef USE_JUMP_TABLES
632 jte = mono_jumptable_add_entries (2);
633 code = mono_arm_load_jumptable_entry_addr (code, jte, ARMREG_IP);
634 ARM_LDR_IMM (code, MONO_ARCH_RGCTX_REG, ARMREG_IP, 0);
635 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_IP, 4);
636 ARM_BX (code, ARMREG_IP);
640 ARM_LDR_IMM (code, MONO_ARCH_RGCTX_REG, ARMREG_PC, 0);
641 ARM_LDR_IMM (code, ARMREG_PC, ARMREG_PC, 0);
642 *(guint32*)code = (guint32)mrgctx;
644 *(guint32*)code = (guint32)addr;
648 g_assert ((code - start) <= buf_len);
650 mono_arch_flush_icache (start, code - start);
651 mono_profiler_code_buffer_new (start, code - start, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
653 mono_tramp_info_register (mono_tramp_info_create (NULL, start, code - start, NULL, unwind_ops), domain);
659 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
665 guint8 **rgctx_null_jumps;
669 MonoJumpInfo *ji = NULL;
670 GSList *unwind_ops = NULL;
671 #ifdef USE_JUMP_TABLES
675 mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
676 index = MONO_RGCTX_SLOT_INDEX (slot);
678 index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
679 for (depth = 0; ; ++depth) {
680 int size = mono_class_rgctx_get_array_size (depth, mrgctx);
682 if (index < size - 1)
687 tramp_size = 64 + 16 * depth;
689 code = buf = mono_global_codeman_reserve (tramp_size);
691 unwind_ops = mono_arch_get_cie_program ();
693 rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
696 /* The vtable/mrgctx is in R0 */
697 g_assert (MONO_ARCH_VTABLE_REG == ARMREG_R0);
701 ARM_MOV_REG_REG (code, ARMREG_R1, ARMREG_R0);
703 /* load rgctx ptr from vtable */
704 g_assert (arm_is_imm12 (MONO_STRUCT_OFFSET (MonoVTable, runtime_generic_context)));
705 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R0, MONO_STRUCT_OFFSET (MonoVTable, runtime_generic_context));
706 /* is the rgctx ptr null? */
707 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
708 /* if yes, jump to actual trampoline */
709 rgctx_null_jumps [njumps ++] = code;
710 ARM_B_COND (code, ARMCOND_EQ, 0);
713 for (i = 0; i < depth; ++i) {
714 /* load ptr to next array */
715 if (mrgctx && i == 0) {
716 g_assert (arm_is_imm12 (MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT));
717 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R1, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT);
719 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_R1, 0);
721 /* is the ptr null? */
722 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
723 /* if yes, jump to actual trampoline */
724 rgctx_null_jumps [njumps ++] = code;
725 ARM_B_COND (code, ARMCOND_EQ, 0);
729 code = mono_arm_emit_load_imm (code, ARMREG_R2, sizeof (gpointer) * (index + 1));
730 ARM_LDR_REG_REG (code, ARMREG_R1, ARMREG_R1, ARMREG_R2);
731 /* is the slot null? */
732 ARM_CMP_REG_IMM (code, ARMREG_R1, 0, 0);
733 /* if yes, jump to actual trampoline */
734 rgctx_null_jumps [njumps ++] = code;
735 ARM_B_COND (code, ARMCOND_EQ, 0);
736 /* otherwise return, result is in R1 */
737 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_R1);
738 code = emit_bx (code, ARMREG_LR);
740 g_assert (njumps <= depth + 2);
741 for (i = 0; i < njumps; ++i)
742 arm_patch (rgctx_null_jumps [i], code);
744 g_free (rgctx_null_jumps);
748 /* The vtable/mrgctx is still in R0 */
751 ji = mono_patch_info_list_prepend (ji, code - buf, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
752 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0);
754 *(gpointer*)code = NULL;
756 ARM_LDR_REG_REG (code, ARMREG_PC, ARMREG_PC, ARMREG_R1);
758 tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), &code_len);
760 /* Jump to the actual trampoline */
761 #ifdef USE_JUMP_TABLES
762 jte = mono_jumptable_add_entry ();
764 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_R1);
765 code = emit_bx (code, ARMREG_R1);
767 ARM_LDR_IMM (code, ARMREG_R1, ARMREG_PC, 0); /* temp reg */
768 code = emit_bx (code, ARMREG_R1);
769 *(gpointer*)code = tramp;
774 mono_arch_flush_icache (buf, code - buf);
775 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
777 g_assert (code - buf <= tramp_size);
779 char *name = mono_get_rgctx_fetch_trampoline_name (slot);
780 *info = mono_tramp_info_create (name, buf, code - buf, ji, unwind_ops);
787 mono_arch_create_general_rgctx_lazy_fetch_trampoline (MonoTrampInfo **info, gboolean aot)
791 MonoJumpInfo *ji = NULL;
792 GSList *unwind_ops = NULL;
798 code = buf = mono_global_codeman_reserve (tramp_size);
800 unwind_ops = mono_arch_get_cie_program ();
802 // FIXME: Currently, we always go to the slow path.
803 /* Load trampoline addr */
804 ARM_LDR_IMM (code, ARMREG_R1, MONO_ARCH_RGCTX_REG, 4);
805 /* The vtable/mrgctx is in R0 */
806 g_assert (MONO_ARCH_VTABLE_REG == ARMREG_R0);
807 code = emit_bx (code, ARMREG_R1);
809 mono_arch_flush_icache (buf, code - buf);
810 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
812 g_assert (code - buf <= tramp_size);
814 *info = mono_tramp_info_create ("rgctx_fetch_trampoline_general", buf, code - buf, ji, unwind_ops);
820 handler_block_trampoline_helper (gpointer *ptr)
822 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
823 return jit_tls->handler_block_return_address;
827 mono_arch_create_handler_block_trampoline (MonoTrampInfo **info, gboolean aot)
832 MonoJumpInfo *ji = NULL;
833 GSList *unwind_ops = NULL;
837 code = buf = mono_global_codeman_reserve (tramp_size);
839 unwind_ops = mono_arch_get_cie_program ();
841 tramp = mono_arch_create_specific_trampoline (NULL, MONO_TRAMPOLINE_HANDLER_BLOCK_GUARD, NULL, NULL);
844 This trampoline restore the call chain of the handler block then jumps into the code that deals with it.
848 * We are in a method frame after the call emitted by OP_CALL_HANDLER.
850 /* Obtain jit_tls->handler_block_return_address */
851 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
853 *(gpointer*)code = handler_block_trampoline_helper;
856 /* Set it as the return address so the trampoline will return to it */
857 ARM_MOV_REG_REG (code, ARMREG_LR, ARMREG_R0);
859 /* Call the trampoline */
860 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_PC, 0);
861 code = emit_bx (code, ARMREG_R0);
862 *(gpointer*)code = tramp;
865 mono_arch_flush_icache (buf, code - buf);
866 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
867 g_assert (code - buf <= tramp_size);
869 *info = mono_tramp_info_create ("handler_block_trampoline", buf, code - buf, ji, unwind_ops);
875 mono_arch_create_sdb_trampoline (gboolean single_step, MonoTrampInfo **info, gboolean aot)
878 GSList *unwind_ops = NULL;
879 MonoJumpInfo *ji = NULL;
882 buf = code = mono_global_codeman_reserve (96);
885 * Construct the MonoContext structure on the stack.
888 frame_size = sizeof (MonoContext);
889 frame_size = ALIGN_TO (frame_size, MONO_ARCH_FRAME_ALIGNMENT);
890 ARM_SUB_REG_IMM8 (code, ARMREG_SP, ARMREG_SP, frame_size);
892 /* save ip, lr and pc into their correspodings ctx.regs slots. */
893 ARM_STR_IMM (code, ARMREG_IP, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs) + sizeof (mgreg_t) * ARMREG_IP);
894 ARM_STR_IMM (code, ARMREG_LR, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_LR);
895 ARM_STR_IMM (code, ARMREG_LR, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_PC);
897 /* save r0..r10 and fp */
898 ARM_ADD_REG_IMM8 (code, ARMREG_IP, ARMREG_SP, MONO_STRUCT_OFFSET (MonoContext, regs));
899 ARM_STM (code, ARMREG_IP, 0x0fff);
901 /* now we can update fp. */
902 ARM_MOV_REG_REG (code, ARMREG_FP, ARMREG_SP);
904 /* make ctx.esp hold the actual value of sp at the beginning of this method. */
905 ARM_ADD_REG_IMM8 (code, ARMREG_R0, ARMREG_FP, frame_size);
906 ARM_STR_IMM (code, ARMREG_R0, ARMREG_IP, 4 * ARMREG_SP);
907 ARM_STR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_SP);
909 /* make ctx.eip hold the address of the call. */
910 ARM_SUB_REG_IMM8 (code, ARMREG_LR, ARMREG_LR, 4);
911 ARM_STR_IMM (code, ARMREG_LR, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, pc));
913 /* r0 now points to the MonoContext */
914 ARM_MOV_REG_REG (code, ARMREG_R0, ARMREG_FP);
918 #ifdef USE_JUMP_TABLES
920 gpointer *jte = mono_jumptable_add_entry ();
921 code = mono_arm_load_jumptable_entry (code, jte, ARMREG_IP);
925 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 0);
928 *(gpointer*)code = debugger_agent_single_step_from_context;
930 *(gpointer*)code = debugger_agent_breakpoint_from_context;
933 ARM_BLX_REG (code, ARMREG_IP);
935 /* we're back; save ctx.eip and ctx.esp into the corresponding regs slots. */
936 ARM_LDR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, pc));
937 ARM_STR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_LR);
938 ARM_STR_IMM (code, ARMREG_R0, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs) + 4 * ARMREG_PC);
940 /* make ip point to the regs array, then restore everything, including pc. */
941 ARM_ADD_REG_IMM8 (code, ARMREG_IP, ARMREG_FP, MONO_STRUCT_OFFSET (MonoContext, regs));
942 ARM_LDM (code, ARMREG_IP, 0xffff);
944 mono_arch_flush_icache (buf, code - buf);
945 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_HELPER, NULL);
947 const char *tramp_name = single_step ? "sdb_single_step_trampoline" : "sdb_breakpoint_trampoline";
948 *info = mono_tramp_info_create (tramp_name, buf, code - buf, ji, unwind_ops);
956 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
958 g_assert_not_reached ();
963 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
965 g_assert_not_reached ();
970 mono_arch_get_unbox_trampoline (MonoMethod *m, gpointer addr)
972 g_assert_not_reached ();
977 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
979 g_assert_not_reached ();
984 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
986 g_assert_not_reached ();
991 mono_arch_create_handler_block_trampoline (MonoTrampInfo **info, gboolean aot)
993 g_assert_not_reached ();
998 mono_arch_create_sdb_trampoline (gboolean single_step, MonoTrampInfo **info, gboolean aot)
1000 g_assert_not_reached ();
1004 #endif /* DISABLE_JIT */
1007 mono_arch_get_call_target (guint8 *code)
1009 guint32 ins = ((guint32*)(gpointer)code) [-1];
1012 /* Should be a 'bl' or a 'b' */
1013 if (((ins >> 25) & 0x7) == 0x5) {
1015 /* Should be a 'bl' */
1016 if ((((ins >> 25) & 0x7) == 0x5) && (((ins >> 24) & 0x1) == 0x1)) {
1018 gint32 disp = ((((gint32)ins) & 0xffffff) << 8) >> 8;
1019 guint8 *target = code - 4 + 8 + (disp * 4);
1028 mono_arch_get_plt_info_offset (guint8 *plt_entry, mgreg_t *regs, guint8 *code)
1030 /* The offset is stored as the 4th word of the plt entry */
1031 return ((guint32*)plt_entry) [3];
1035 * Return the address of the PLT entry called by the thumb code CODE.
1038 mono_arm_get_thumb_plt_entry (guint8 *code)
1040 int s, j1, j2, imm10, imm11, i1, i2, imm32;
1045 /* code should be right after a BL */
1046 code = (guint8*)((mgreg_t)code & ~1);
1047 base = (guint8*)((mgreg_t)code & ~3);
1049 t1 = ((guint16*)bl) [0];
1050 t2 = ((guint16*)bl) [1];
1052 g_assert ((t1 >> 11) == 0x1e);
1054 s = (t1 >> 10) & 0x1;
1055 imm10 = (t1 >> 0) & 0x3ff;
1056 j1 = (t2 >> 13) & 0x1;
1057 j2 = (t2 >> 11) & 0x1;
1060 i1 = (s ^ j1) ? 0 : 1;
1061 i2 = (s ^ j2) ? 0 : 1;
1063 imm32 = (imm11 << 1) | (imm10 << 12) | (i2 << 22) | (i1 << 23);
1065 /* Sign extend from 24 bits to 32 bits */
1066 imm32 = ((gint32)imm32 << 8) >> 8;
1068 target = code + imm32;
1070 /* target now points to the thumb plt entry */
1071 /* ldr.w r12, [pc, #8] */
1072 g_assert (((guint16*)target) [0] == 0xf8df);
1073 g_assert (((guint16*)target) [1] == 0xc008);
1076 * The PLT info offset is at offset 16, but mono_arch_get_plt_entry_offset () returns
1077 * the 3rd word, so compensate by returning a different value.
1087 * mono_arch_get_gsharedvt_arg_trampoline:
1089 * See tramp-x86.c for documentation.
1092 mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
1096 gpointer *constants;
1100 buf = code = mono_domain_code_reserve (domain, buf_len);
1102 /* Similar to the specialized trampoline code */
1103 ARM_PUSH (code, (1 << ARMREG_R0) | (1 << ARMREG_R1) | (1 << ARMREG_R2) | (1 << ARMREG_R3) | (1 << ARMREG_LR));
1104 ARM_LDR_IMM (code, ARMREG_IP, ARMREG_PC, 8);
1105 /* arg is passed in LR */
1106 ARM_LDR_IMM (code, ARMREG_LR, ARMREG_PC, 0);
1107 code = emit_bx (code, ARMREG_IP);
1108 constants = (gpointer*)code;
1109 constants [0] = arg;
1110 constants [1] = addr;
1113 g_assert ((code - buf) <= buf_len);
1115 nacl_domain_code_validate (domain, &buf, buf_len, &code);
1116 mono_arch_flush_icache (buf, code - buf);
1117 mono_profiler_code_buffer_new (buf, code - buf, MONO_PROFILER_CODE_BUFFER_GENERICS_TRAMPOLINE, NULL);
1119 mono_tramp_info_register (mono_tramp_info_create (NULL, buf, code - buf, NULL, NULL), domain);
1127 mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
1129 g_assert_not_reached ();
1135 #if defined(ENABLE_GSHAREDVT)
1137 #include "../../../mono-extensions/mono/mini/tramp-arm-gsharedvt.c"
1142 mono_arm_start_gsharedvt_call (GSharedVtCallInfo *info, gpointer *caller, gpointer *callee, gpointer mrgctx_reg)
1144 g_assert_not_reached ();
1149 mono_arch_get_gsharedvt_trampoline (MonoTrampInfo **info, gboolean aot)
1155 #endif /* !MONOTOUCH */