1 /*
2 * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2013, Red Hat Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "asm/macroAssembler.hpp"
28 #include "asm/macroAssembler.inline.hpp"
29 #include "code/debugInfoRec.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "oops/compiledICHolder.hpp"
34 #include "prims/jvmtiRedefineClassesTrace.hpp"
35 #include "runtime/sharedRuntime.hpp"
36 #include "runtime/vframeArray.hpp"
37 #include "vmreg_aarch64.inline.hpp"
38 #ifdef COMPILER1
39 #include "c1/c1_Runtime1.hpp"
40 #endif
41 #ifdef COMPILER2
42 #include "opto/runtime.hpp"
43 #endif
44
45 #define __ masm->
46
47 const int StackAlignmentInSlots = StackAlignmentInBytes / VMRegImpl::stack_slot_size;
48
49 class SimpleRuntimeFrame {
50
51 public:
52
53 // Most of the runtime stubs have this simple frame layout.
54 // This class exists to make the layout shared in one place.
55 // Offsets are for compiler stack slots, which are jints.
56 enum layout {
57 // The frame sender code expects that rbp will be in the "natural" place and
58 // will override any oopMap setting for it. We must therefore force the layout
59 // so that it agrees with the frame sender code.
60 // we don't expect any arg reg save area so aarch64 asserts that
61 // frame::arg_reg_save_area_bytes == 0
62 rbp_off = 0,
63 rbp_off2,
64 return_off, return_off2,
65 framesize
66 };
67 };
68
69 // FIXME -- this is used by C1
70 class RegisterSaver {
71 public:
72 static OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors = false);
73 static void restore_live_registers(MacroAssembler* masm, bool restore_vectors = false);
74
75 // Offsets into the register save area
76 // Used by deoptimization when it is managing result register
77 // values on its own
78
79 static int r0_offset_in_bytes(void) { return (32 + r0->encoding()) * wordSize; }
80 static int reg_offset_in_bytes(Register r) { return r0_offset_in_bytes() + r->encoding() * wordSize; }
81 static int rmethod_offset_in_bytes(void) { return reg_offset_in_bytes(rmethod); }
82 static int rscratch1_offset_in_bytes(void) { return (32 + rscratch1->encoding()) * wordSize; }
83 static int v0_offset_in_bytes(void) { return 0; }
84 static int return_offset_in_bytes(void) { return (32 /* floats*/ + 31 /* gregs*/) * wordSize; }
85
86 // During deoptimization only the result registers need to be restored,
87 // all the other values have already been extracted.
88 static void restore_result_registers(MacroAssembler* masm);
89
90 // Capture info about frame layout
91 enum layout {
92 fpu_state_off = 0,
93 fpu_state_end = fpu_state_off+FPUStateSizeInWords-1,
94 // The frame sender code expects that rfp will be in
95 // the "natural" place and will override any oopMap
96 // setting for it. We must therefore force the layout
97 // so that it agrees with the frame sender code.
98 r0_off = fpu_state_off+FPUStateSizeInWords,
99 rfp_off = r0_off + 30 * 2,
100 return_off = rfp_off + 2, // slot for return address
101 reg_save_size = return_off + 2};
102
103 };
104
105 OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors) {
106 #ifdef COMPILER2
107 if (save_vectors) {
108 // Save upper half of vector registers
109 int vect_words = 32 * 8 / wordSize;
110 additional_frame_words += vect_words;
111 }
112 #else
113 assert(!save_vectors, "vectors are generated only by C2");
114 #endif
115
116 int frame_size_in_bytes = round_to(additional_frame_words*wordSize +
117 reg_save_size*BytesPerInt, 16);
118 // OopMap frame size is in compiler stack slots (jint's) not bytes or words
119 int frame_size_in_slots = frame_size_in_bytes / BytesPerInt;
120 // The caller will allocate additional_frame_words
121 int additional_frame_slots = additional_frame_words*wordSize / BytesPerInt;
122 // CodeBlob frame size is in words.
123 int frame_size_in_words = frame_size_in_bytes / wordSize;
124 *total_frame_words = frame_size_in_words;
125
126 // Save Integer and Float registers.
127
128 __ enter();
129 __ push_CPU_state(save_vectors);
130
131 // Set an oopmap for the call site. This oopmap will map all
132 // oop-registers and debug-info registers as callee-saved. This
133 // will allow deoptimization at this safepoint to find all possible
134 // debug-info recordings, as well as let GC find all oops.
135
136 OopMapSet *oop_maps = new OopMapSet();
137 OopMap* oop_map = new OopMap(frame_size_in_slots, 0);
138
139 for (int i = 0; i < RegisterImpl::number_of_registers; i++) {
140 Register r = as_Register(i);
141 if (r < rheapbase && r != rscratch1 && r != rscratch2) {
142 int sp_offset = 2 * (i + 32); // SP offsets are in 4-byte words,
143 // register slots are 8 bytes
144 // wide, 32 floating-point
145 // registers
146 oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset + additional_frame_slots),
147 r->as_VMReg());
148 }
149 }
150
151 for (int i = 0; i < FloatRegisterImpl::number_of_registers; i++) {
152 FloatRegister r = as_FloatRegister(i);
153 int sp_offset = save_vectors ? (4 * i) : (2 * i);
154 oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset),
155 r->as_VMReg());
156 }
157
158 return oop_map;
159 }
160
161 void RegisterSaver::restore_live_registers(MacroAssembler* masm, bool restore_vectors) {
162 #ifndef COMPILER2
163 assert(!restore_vectors, "vectors are generated only by C2");
164 #endif
165 __ pop_CPU_state(restore_vectors);
166 __ leave();
167 }
168
169 void RegisterSaver::restore_result_registers(MacroAssembler* masm) {
170
171 // Just restore result register. Only used by deoptimization. By
172 // now any callee save register that needs to be restored to a c2
173 // caller of the deoptee has been extracted into the vframeArray
174 // and will be stuffed into the c2i adapter we create for later
175 // restoration so only result registers need to be restored here.
176
177 // Restore fp result register
178 __ ldrd(v0, Address(sp, v0_offset_in_bytes()));
179 // Restore integer result register
180 __ ldr(r0, Address(sp, r0_offset_in_bytes()));
181
182 // Pop all of the register save are off the stack
183 __ add(sp, sp, round_to(return_offset_in_bytes(), 16));
184 }
185
186 // Is vector's size (in bytes) bigger than a size saved by default?
187 // 8 bytes vector registers are saved by default on AArch64.
188 bool SharedRuntime::is_wide_vector(int size) {
189 return size > 8;
190 }
191 // The java_calling_convention describes stack locations as ideal slots on
192 // a frame with no abi restrictions. Since we must observe abi restrictions
193 // (like the placement of the register window) the slots must be biased by
194 // the following value.
195 static int reg2offset_in(VMReg r) {
196 // Account for saved rfp and lr
197 // This should really be in_preserve_stack_slots
198 return (r->reg2stack() + 4) * VMRegImpl::stack_slot_size;
199 }
200
201 static int reg2offset_out(VMReg r) {
202 return (r->reg2stack() + SharedRuntime::out_preserve_stack_slots()) * VMRegImpl::stack_slot_size;
203 }
204
205 // ---------------------------------------------------------------------------
206 // Read the array of BasicTypes from a signature, and compute where the
207 // arguments should go. Values in the VMRegPair regs array refer to 4-byte
208 // quantities. Values less than VMRegImpl::stack0 are registers, those above
209 // refer to 4-byte stack slots. All stack slots are based off of the stack pointer
210 // as framesizes are fixed.
211 // VMRegImpl::stack0 refers to the first slot 0(sp).
212 // and VMRegImpl::stack0+1 refers to the memory word 4-byes higher. Register
213 // up to RegisterImpl::number_of_registers) are the 64-bit
214 // integer registers.
215
216 // Note: the INPUTS in sig_bt are in units of Java argument words,
217 // which are 64-bit. The OUTPUTS are in 32-bit units.
218
219 // The Java calling convention is a "shifted" version of the C ABI.
220 // By skipping the first C ABI register we can call non-static jni
221 // methods with small numbers of arguments without having to shuffle
222 // the arguments at all. Since we control the java ABI we ought to at
223 // least get some advantage out of it.
224
225 int SharedRuntime::java_calling_convention(const BasicType *sig_bt,
226 VMRegPair *regs,
227 int total_args_passed,
228 int is_outgoing) {
229
230 // Create the mapping between argument positions and
231 // registers.
232 static const Register INT_ArgReg[Argument::n_int_register_parameters_j] = {
233 j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7
234 };
235 static const FloatRegister FP_ArgReg[Argument::n_float_register_parameters_j] = {
236 j_farg0, j_farg1, j_farg2, j_farg3,
237 j_farg4, j_farg5, j_farg6, j_farg7
238 };
239
240
241 uint int_args = 0;
242 uint fp_args = 0;
243 uint stk_args = 0; // inc by 2 each time
244
245 for (int i = 0; i < total_args_passed; i++) {
246 switch (sig_bt[i]) {
247 case T_BOOLEAN:
248 case T_CHAR:
249 case T_BYTE:
250 case T_SHORT:
251 case T_INT:
252 if (int_args < Argument::n_int_register_parameters_j) {
253 regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
254 } else {
255 regs[i].set1(VMRegImpl::stack2reg(stk_args));
256 stk_args += 2;
257 }
258 break;
259 case T_VOID:
260 // halves of T_LONG or T_DOUBLE
261 assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
262 regs[i].set_bad();
263 break;
264 case T_LONG:
265 assert(sig_bt[i + 1] == T_VOID, "expecting half");
266 // fall through
267 case T_OBJECT:
268 case T_ARRAY:
269 case T_ADDRESS:
270 if (int_args < Argument::n_int_register_parameters_j) {
271 regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
272 } else {
273 regs[i].set2(VMRegImpl::stack2reg(stk_args));
274 stk_args += 2;
275 }
276 break;
277 case T_FLOAT:
278 if (fp_args < Argument::n_float_register_parameters_j) {
279 regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
280 } else {
281 regs[i].set1(VMRegImpl::stack2reg(stk_args));
282 stk_args += 2;
283 }
284 break;
285 case T_DOUBLE:
286 assert(sig_bt[i + 1] == T_VOID, "expecting half");
287 if (fp_args < Argument::n_float_register_parameters_j) {
288 regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
289 } else {
290 regs[i].set2(VMRegImpl::stack2reg(stk_args));
291 stk_args += 2;
292 }
293 break;
294 default:
295 ShouldNotReachHere();
296 break;
297 }
298 }
299
300 return round_to(stk_args, 2);
301 }
302
303 // Patch the callers callsite with entry to compiled code if it exists.
304 static void patch_callers_callsite(MacroAssembler *masm) {
305 Label L;
306 __ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
307 __ cbz(rscratch1, L);
308
309 __ enter();
310 __ push_CPU_state();
311
312 // VM needs caller's callsite
313 // VM needs target method
314 // This needs to be a long call since we will relocate this adapter to
315 // the codeBuffer and it may not reach
316
317 #ifndef PRODUCT
318 assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
319 #endif
320
321 __ mov(c_rarg0, rmethod);
322 __ mov(c_rarg1, lr);
323 __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite)));
324 __ blr(rscratch1);
325 __ maybe_isb();
326
327 __ pop_CPU_state();
328 // restore sp
329 __ leave();
330 __ bind(L);
331 }
332
333 static void gen_c2i_adapter(MacroAssembler *masm,
334 int total_args_passed,
335 int comp_args_on_stack,
336 const BasicType *sig_bt,
337 const VMRegPair *regs,
338 Label& skip_fixup) {
339 // Before we get into the guts of the C2I adapter, see if we should be here
340 // at all. We've come from compiled code and are attempting to jump to the
341 // interpreter, which means the caller made a static call to get here
342 // (vcalls always get a compiled target if there is one). Check for a
343 // compiled target. If there is one, we need to patch the caller's call.
344 patch_callers_callsite(masm);
345
346 __ bind(skip_fixup);
347
348 int words_pushed = 0;
349
350 // Since all args are passed on the stack, total_args_passed *
351 // Interpreter::stackElementSize is the space we need.
352
353 int extraspace = total_args_passed * Interpreter::stackElementSize;
354
355 __ mov(r13, sp);
356
357 // stack is aligned, keep it that way
358 extraspace = round_to(extraspace, 2*wordSize);
359
360 if (extraspace)
361 __ sub(sp, sp, extraspace);
362
363 // Now write the args into the outgoing interpreter space
364 for (int i = 0; i < total_args_passed; i++) {
365 if (sig_bt[i] == T_VOID) {
366 assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
367 continue;
368 }
369
370 // offset to start parameters
371 int st_off = (total_args_passed - i - 1) * Interpreter::stackElementSize;
372 int next_off = st_off - Interpreter::stackElementSize;
373
374 // Say 4 args:
375 // i st_off
376 // 0 32 T_LONG
377 // 1 24 T_VOID
378 // 2 16 T_OBJECT
379 // 3 8 T_BOOL
380 // - 0 return address
381 //
382 // However to make thing extra confusing. Because we can fit a long/double in
383 // a single slot on a 64 bt vm and it would be silly to break them up, the interpreter
384 // leaves one slot empty and only stores to a single slot. In this case the
385 // slot that is occupied is the T_VOID slot. See I said it was confusing.
386
387 VMReg r_1 = regs[i].first();
388 VMReg r_2 = regs[i].second();
389 if (!r_1->is_valid()) {
390 assert(!r_2->is_valid(), "");
391 continue;
392 }
393 if (r_1->is_stack()) {
394 // memory to memory use rscratch1
395 int ld_off = (r_1->reg2stack() * VMRegImpl::stack_slot_size
396 + extraspace
397 + words_pushed * wordSize);
398 if (!r_2->is_valid()) {
399 // sign extend??
400 __ ldrw(rscratch1, Address(sp, ld_off));
401 __ str(rscratch1, Address(sp, st_off));
402
403 } else {
404
405 __ ldr(rscratch1, Address(sp, ld_off));
406
407 // Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
408 // T_DOUBLE and T_LONG use two slots in the interpreter
409 if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
410 // ld_off == LSW, ld_off+wordSize == MSW
411 // st_off == MSW, next_off == LSW
412 __ str(rscratch1, Address(sp, next_off));
413 #ifdef ASSERT
414 // Overwrite the unused slot with known junk
415 __ mov(rscratch1, 0xdeadffffdeadaaaaul);
416 __ str(rscratch1, Address(sp, st_off));
417 #endif /* ASSERT */
418 } else {
419 __ str(rscratch1, Address(sp, st_off));
420 }
421 }
422 } else if (r_1->is_Register()) {
423 Register r = r_1->as_Register();
424 if (!r_2->is_valid()) {
425 // must be only an int (or less ) so move only 32bits to slot
426 // why not sign extend??
427 __ str(r, Address(sp, st_off));
428 } else {
429 // Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
430 // T_DOUBLE and T_LONG use two slots in the interpreter
431 if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
432 // long/double in gpr
433 #ifdef ASSERT
434 // Overwrite the unused slot with known junk
435 __ mov(rscratch1, 0xdeadffffdeadaaabul);
436 __ str(rscratch1, Address(sp, st_off));
437 #endif /* ASSERT */
438 __ str(r, Address(sp, next_off));
439 } else {
440 __ str(r, Address(sp, st_off));
441 }
442 }
443 } else {
444 assert(r_1->is_FloatRegister(), "");
445 if (!r_2->is_valid()) {
446 // only a float use just part of the slot
447 __ strs(r_1->as_FloatRegister(), Address(sp, st_off));
448 } else {
449 #ifdef ASSERT
450 // Overwrite the unused slot with known junk
451 __ mov(rscratch1, 0xdeadffffdeadaaacul);
452 __ str(rscratch1, Address(sp, st_off));
453 #endif /* ASSERT */
454 __ strd(r_1->as_FloatRegister(), Address(sp, next_off));
455 }
456 }
457 }
458
459 __ mov(esp, sp); // Interp expects args on caller's expression stack
460
461 __ ldr(rscratch1, Address(rmethod, in_bytes(Method::interpreter_entry_offset())));
462 __ br(rscratch1);
463 }
464
465
466 static void gen_i2c_adapter(MacroAssembler *masm,
467 int total_args_passed,
468 int comp_args_on_stack,
469 const BasicType *sig_bt,
470 const VMRegPair *regs) {
471
472 // Note: r13 contains the senderSP on entry. We must preserve it since
473 // we may do a i2c -> c2i transition if we lose a race where compiled
474 // code goes non-entrant while we get args ready.
475
476 // In addition we use r13 to locate all the interpreter args because
477 // we must align the stack to 16 bytes.
478
479 // Adapters are frameless.
480
481 // An i2c adapter is frameless because the *caller* frame, which is
482 // interpreted, routinely repairs its own esp (from
483 // interpreter_frame_last_sp), even if a callee has modified the
484 // stack pointer. It also recalculates and aligns sp.
485
486 // A c2i adapter is frameless because the *callee* frame, which is
487 // interpreted, routinely repairs its caller's sp (from sender_sp,
488 // which is set up via the senderSP register).
489
490 // In other words, if *either* the caller or callee is interpreted, we can
491 // get the stack pointer repaired after a call.
492
493 // This is why c2i and i2c adapters cannot be indefinitely composed.
494 // In particular, if a c2i adapter were to somehow call an i2c adapter,
495 // both caller and callee would be compiled methods, and neither would
496 // clean up the stack pointer changes performed by the two adapters.
497 // If this happens, control eventually transfers back to the compiled
498 // caller, but with an uncorrected stack, causing delayed havoc.
499
500 if (VerifyAdapterCalls &&
501 (Interpreter::code() != NULL || StubRoutines::code1() != NULL)) {
502 #if 0
503 // So, let's test for cascading c2i/i2c adapters right now.
504 // assert(Interpreter::contains($return_addr) ||
505 // StubRoutines::contains($return_addr),
506 // "i2c adapter must return to an interpreter frame");
507 __ block_comment("verify_i2c { ");
508 Label L_ok;
509 if (Interpreter::code() != NULL)
510 range_check(masm, rax, r11,
511 Interpreter::code()->code_start(), Interpreter::code()->code_end(),
512 L_ok);
513 if (StubRoutines::code1() != NULL)
514 range_check(masm, rax, r11,
515 StubRoutines::code1()->code_begin(), StubRoutines::code1()->code_end(),
516 L_ok);
517 if (StubRoutines::code2() != NULL)
518 range_check(masm, rax, r11,
519 StubRoutines::code2()->code_begin(), StubRoutines::code2()->code_end(),
520 L_ok);
521 const char* msg = "i2c adapter must return to an interpreter frame";
522 __ block_comment(msg);
523 __ stop(msg);
524 __ bind(L_ok);
525 __ block_comment("} verify_i2ce ");
526 #endif
527 }
528
529 // Cut-out for having no stack args.
530 int comp_words_on_stack = round_to(comp_args_on_stack*VMRegImpl::stack_slot_size, wordSize)>>LogBytesPerWord;
531 if (comp_args_on_stack) {
532 __ sub(rscratch1, sp, comp_words_on_stack * wordSize);
533 __ andr(sp, rscratch1, -16);
534 }
535
536 // Will jump to the compiled code just as if compiled code was doing it.
537 // Pre-load the register-jump target early, to schedule it better.
538 __ ldr(rscratch1, Address(rmethod, in_bytes(Method::from_compiled_offset())));
539
540 // Now generate the shuffle code.
541 for (int i = 0; i < total_args_passed; i++) {
542 if (sig_bt[i] == T_VOID) {
543 assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
544 continue;
545 }
546
547 // Pick up 0, 1 or 2 words from SP+offset.
548
549 assert(!regs[i].second()->is_valid() || regs[i].first()->next() == regs[i].second(),
550 "scrambled load targets?");
551 // Load in argument order going down.
552 int ld_off = (total_args_passed - i - 1)*Interpreter::stackElementSize;
553 // Point to interpreter value (vs. tag)
554 int next_off = ld_off - Interpreter::stackElementSize;
555 //
556 //
557 //
558 VMReg r_1 = regs[i].first();
559 VMReg r_2 = regs[i].second();
560 if (!r_1->is_valid()) {
561 assert(!r_2->is_valid(), "");
562 continue;
563 }
564 if (r_1->is_stack()) {
565 // Convert stack slot to an SP offset (+ wordSize to account for return address )
566 int st_off = regs[i].first()->reg2stack()*VMRegImpl::stack_slot_size;
567 if (!r_2->is_valid()) {
568 // sign extend???
569 __ ldrsw(rscratch2, Address(esp, ld_off));
570 __ str(rscratch2, Address(sp, st_off));
571 } else {
572 //
573 // We are using two optoregs. This can be either T_OBJECT,
574 // T_ADDRESS, T_LONG, or T_DOUBLE the interpreter allocates
575 // two slots but only uses one for thr T_LONG or T_DOUBLE case
576 // So we must adjust where to pick up the data to match the
577 // interpreter.
578 //
579 // Interpreter local[n] == MSW, local[n+1] == LSW however locals
580 // are accessed as negative so LSW is at LOW address
581
582 // ld_off is MSW so get LSW
583 const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
584 next_off : ld_off;
585 __ ldr(rscratch2, Address(esp, offset));
586 // st_off is LSW (i.e. reg.first())
587 __ str(rscratch2, Address(sp, st_off));
588 }
589 } else if (r_1->is_Register()) { // Register argument
590 Register r = r_1->as_Register();
591 if (r_2->is_valid()) {
592 //
593 // We are using two VMRegs. This can be either T_OBJECT,
594 // T_ADDRESS, T_LONG, or T_DOUBLE the interpreter allocates
595 // two slots but only uses one for thr T_LONG or T_DOUBLE case
596 // So we must adjust where to pick up the data to match the
597 // interpreter.
598
599 const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
600 next_off : ld_off;
601
602 // this can be a misaligned move
603 __ ldr(r, Address(esp, offset));
604 } else {
605 // sign extend and use a full word?
606 __ ldrw(r, Address(esp, ld_off));
607 }
608 } else {
609 if (!r_2->is_valid()) {
610 __ ldrs(r_1->as_FloatRegister(), Address(esp, ld_off));
611 } else {
612 __ ldrd(r_1->as_FloatRegister(), Address(esp, next_off));
613 }
614 }
615 }
616
617 // 6243940 We might end up in handle_wrong_method if
618 // the callee is deoptimized as we race thru here. If that
619 // happens we don't want to take a safepoint because the
620 // caller frame will look interpreted and arguments are now
621 // "compiled" so it is much better to make this transition
622 // invisible to the stack walking code. Unfortunately if
623 // we try and find the callee by normal means a safepoint
624 // is possible. So we stash the desired callee in the thread
625 // and the vm will find there should this case occur.
626
627 __ str(rmethod, Address(rthread, JavaThread::callee_target_offset()));
628
629 __ br(rscratch1);
630 }
631
632 // ---------------------------------------------------------------
633 AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
634 int total_args_passed,
635 int comp_args_on_stack,
636 const BasicType *sig_bt,
637 const VMRegPair *regs,
638 AdapterFingerPrint* fingerprint) {
639 address i2c_entry = __ pc();
640
641 gen_i2c_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs);
642
643 address c2i_unverified_entry = __ pc();
644 Label skip_fixup;
645
646 Label ok;
647
648 Register holder = rscratch2;
649 Register receiver = j_rarg0;
650 Register tmp = r10; // A call-clobbered register not used for arg passing
651
652 // -------------------------------------------------------------------------
653 // Generate a C2I adapter. On entry we know rmethod holds the Method* during calls
654 // to the interpreter. The args start out packed in the compiled layout. They
655 // need to be unpacked into the interpreter layout. This will almost always
656 // require some stack space. We grow the current (compiled) stack, then repack
657 // the args. We finally end in a jump to the generic interpreter entry point.
658 // On exit from the interpreter, the interpreter will restore our SP (lest the
659 // compiled code, which relys solely on SP and not FP, get sick).
660
661 {
662 __ block_comment("c2i_unverified_entry {");
663 __ load_klass(rscratch1, receiver);
664 __ ldr(tmp, Address(holder, CompiledICHolder::holder_klass_offset()));
665 __ cmp(rscratch1, tmp);
666 __ ldr(rmethod, Address(holder, CompiledICHolder::holder_metadata_offset()));
667 __ br(Assembler::EQ, ok);
668 __ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
669
670 __ bind(ok);
671 // Method might have been compiled since the call site was patched to
672 // interpreted; if that is the case treat it as a miss so we can get
673 // the call site corrected.
674 __ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
675 __ cbz(rscratch1, skip_fixup);
676 __ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
677 __ block_comment("} c2i_unverified_entry");
678 }
679
680 address c2i_entry = __ pc();
681
682 gen_c2i_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs, skip_fixup);
683
684 __ flush();
685 return AdapterHandlerLibrary::new_entry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);
686 }
687
688 int SharedRuntime::c_calling_convention(const BasicType *sig_bt,
689 VMRegPair *regs,
690 VMRegPair *regs2,
691 int total_args_passed) {
692 assert(regs2 == NULL, "not needed on AArch64");
693 // We return the amount of VMRegImpl stack slots we need to reserve for all
694 // the arguments NOT counting out_preserve_stack_slots.
695
696 static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
697 c_rarg0, c_rarg1, c_rarg2, c_rarg3, c_rarg4, c_rarg5, c_rarg6, c_rarg7
698 };
699 static const FloatRegister FP_ArgReg[Argument::n_float_register_parameters_c] = {
700 c_farg0, c_farg1, c_farg2, c_farg3,
701 c_farg4, c_farg5, c_farg6, c_farg7
702 };
703
704 uint int_args = 0;
705 uint fp_args = 0;
706 uint stk_args = 0; // inc by 2 each time
707
708 for (int i = 0; i < total_args_passed; i++) {
709 switch (sig_bt[i]) {
710 case T_BOOLEAN:
711 case T_CHAR:
712 case T_BYTE:
713 case T_SHORT:
714 case T_INT:
715 if (int_args < Argument::n_int_register_parameters_c) {
716 regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
717 #ifdef _WIN64
718 fp_args++;
719 // Allocate slots for callee to stuff register args the stack.
720 stk_args += 2;
721 #endif
722 } else {
723 regs[i].set1(VMRegImpl::stack2reg(stk_args));
724 stk_args += 2;
725 }
726 break;
727 case T_LONG:
728 assert(sig_bt[i + 1] == T_VOID, "expecting half");
729 // fall through
730 case T_OBJECT:
731 case T_ARRAY:
732 case T_ADDRESS:
733 case T_METADATA:
734 if (int_args < Argument::n_int_register_parameters_c) {
735 regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
736 #ifdef _WIN64
737 fp_args++;
738 stk_args += 2;
739 #endif
740 } else {
741 regs[i].set2(VMRegImpl::stack2reg(stk_args));
742 stk_args += 2;
743 }
744 break;
745 case T_FLOAT:
746 if (fp_args < Argument::n_float_register_parameters_c) {
747 regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
748 #ifdef _WIN64
749 int_args++;
750 // Allocate slots for callee to stuff register args the stack.
751 stk_args += 2;
752 #endif
753 } else {
754 regs[i].set1(VMRegImpl::stack2reg(stk_args));
755 stk_args += 2;
756 }
757 break;
758 case T_DOUBLE:
759 assert(sig_bt[i + 1] == T_VOID, "expecting half");
760 if (fp_args < Argument::n_float_register_parameters_c) {
761 regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
762 #ifdef _WIN64
763 int_args++;
764 // Allocate slots for callee to stuff register args the stack.
765 stk_args += 2;
766 #endif
767 } else {
768 regs[i].set2(VMRegImpl::stack2reg(stk_args));
769 stk_args += 2;
770 }
771 break;
772 case T_VOID: // Halves of longs and doubles
773 assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
774 regs[i].set_bad();
775 break;
776 default:
777 ShouldNotReachHere();
778 break;
779 }
780 }
781 #ifdef _WIN64
782 // windows abi requires that we always allocate enough stack space
783 // for 4 64bit registers to be stored down.
784 if (stk_args < 8) {
785 stk_args = 8;
786 }
787 #endif // _WIN64
788
789 return stk_args;
790 }
791
792 // On 64 bit we will store integer like items to the stack as
793 // 64 bits items (sparc abi) even though java would only store
794 // 32bits for a parameter. On 32bit it will simply be 32 bits
795 // So this routine will do 32->32 on 32bit and 32->64 on 64bit
796 static void move32_64(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
797 if (src.first()->is_stack()) {
798 if (dst.first()->is_stack()) {
799 // stack to stack
800 __ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
801 __ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
802 } else {
803 // stack to reg
804 __ ldrsw(dst.first()->as_Register(), Address(rfp, reg2offset_in(src.first())));
805 }
806 } else if (dst.first()->is_stack()) {
807 // reg to stack
808 // Do we really have to sign extend???
809 // __ movslq(src.first()->as_Register(), src.first()->as_Register());
810 __ str(src.first()->as_Register(), Address(sp, reg2offset_out(dst.first())));
811 } else {
812 if (dst.first() != src.first()) {
813 __ sxtw(dst.first()->as_Register(), src.first()->as_Register());
814 }
815 }
816 }
817
818 // An oop arg. Must pass a handle not the oop itself
819 static void object_move(MacroAssembler* masm,
820 OopMap* map,
821 int oop_handle_offset,
822 int framesize_in_slots,
823 VMRegPair src,
824 VMRegPair dst,
825 bool is_receiver,
826 int* receiver_offset) {
827
828 // must pass a handle. First figure out the location we use as a handle
829
830 Register rHandle = dst.first()->is_stack() ? rscratch2 : dst.first()->as_Register();
831
832 // See if oop is NULL if it is we need no handle
833
834 if (src.first()->is_stack()) {
835
836 // Oop is already on the stack as an argument
837 int offset_in_older_frame = src.first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();
838 map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + framesize_in_slots));
839 if (is_receiver) {
840 *receiver_offset = (offset_in_older_frame + framesize_in_slots) * VMRegImpl::stack_slot_size;
841 }
842
843 __ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
844 __ lea(rHandle, Address(rfp, reg2offset_in(src.first())));
845 // conditionally move a NULL
846 __ cmp(rscratch1, zr);
847 __ csel(rHandle, zr, rHandle, Assembler::EQ);
848 } else {
849
850 // Oop is in an a register we must store it to the space we reserve
851 // on the stack for oop_handles and pass a handle if oop is non-NULL
852
853 const Register rOop = src.first()->as_Register();
854 int oop_slot;
855 if (rOop == j_rarg0)
856 oop_slot = 0;
857 else if (rOop == j_rarg1)
858 oop_slot = 1;
859 else if (rOop == j_rarg2)
860 oop_slot = 2;
861 else if (rOop == j_rarg3)
862 oop_slot = 3;
863 else if (rOop == j_rarg4)
864 oop_slot = 4;
865 else if (rOop == j_rarg5)
866 oop_slot = 5;
867 else if (rOop == j_rarg6)
868 oop_slot = 6;
869 else {
870 assert(rOop == j_rarg7, "wrong register");
871 oop_slot = 7;
872 }
873
874 oop_slot = oop_slot * VMRegImpl::slots_per_word + oop_handle_offset;
875 int offset = oop_slot*VMRegImpl::stack_slot_size;
876
877 map->set_oop(VMRegImpl::stack2reg(oop_slot));
878 // Store oop in handle area, may be NULL
879 __ str(rOop, Address(sp, offset));
880 if (is_receiver) {
881 *receiver_offset = offset;
882 }
883
884 __ cmp(rOop, zr);
885 __ lea(rHandle, Address(sp, offset));
886 // conditionally move a NULL
887 __ csel(rHandle, zr, rHandle, Assembler::EQ);
888 }
889
890 // If arg is on the stack then place it otherwise it is already in correct reg.
891 if (dst.first()->is_stack()) {
892 __ str(rHandle, Address(sp, reg2offset_out(dst.first())));
893 }
894 }
895
896 // A float arg may have to do float reg int reg conversion
897 static void float_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
898 assert(src.first()->is_stack() && dst.first()->is_stack() ||
899 src.first()->is_reg() && dst.first()->is_reg(), "Unexpected error");
900 if (src.first()->is_stack()) {
901 if (dst.first()->is_stack()) {
902 __ ldrw(rscratch1, Address(rfp, reg2offset_in(src.first())));
903 __ strw(rscratch1, Address(sp, reg2offset_out(dst.first())));
904 } else {
905 ShouldNotReachHere();
906 }
907 } else if (src.first() != dst.first()) {
908 if (src.is_single_phys_reg() && dst.is_single_phys_reg())
909 __ fmovs(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
910 else
911 ShouldNotReachHere();
912 }
913 }
914
915 // A long move
916 static void long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
917 if (src.first()->is_stack()) {
918 if (dst.first()->is_stack()) {
919 // stack to stack
920 __ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
921 __ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
922 } else {
923 // stack to reg
924 __ ldr(dst.first()->as_Register(), Address(rfp, reg2offset_in(src.first())));
925 }
926 } else if (dst.first()->is_stack()) {
927 // reg to stack
928 // Do we really have to sign extend???
929 // __ movslq(src.first()->as_Register(), src.first()->as_Register());
930 __ str(src.first()->as_Register(), Address(sp, reg2offset_out(dst.first())));
931 } else {
932 if (dst.first() != src.first()) {
933 __ mov(dst.first()->as_Register(), src.first()->as_Register());
934 }
935 }
936 }
937
938
939 // A double move
940 static void double_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
941 assert(src.first()->is_stack() && dst.first()->is_stack() ||
942 src.first()->is_reg() && dst.first()->is_reg(), "Unexpected error");
943 if (src.first()->is_stack()) {
944 if (dst.first()->is_stack()) {
945 __ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
946 __ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
947 } else {
948 ShouldNotReachHere();
949 }
950 } else if (src.first() != dst.first()) {
951 if (src.is_single_phys_reg() && dst.is_single_phys_reg())
952 __ fmovd(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
953 else
954 ShouldNotReachHere();
955 }
956 }
957
958
959 void SharedRuntime::save_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
960 // We always ignore the frame_slots arg and just use the space just below frame pointer
961 // which by this time is free to use
962 switch (ret_type) {
963 case T_FLOAT:
964 __ strs(v0, Address(rfp, -wordSize));
965 break;
966 case T_DOUBLE:
967 __ strd(v0, Address(rfp, -wordSize));
968 break;
969 case T_VOID: break;
970 default: {
971 __ str(r0, Address(rfp, -wordSize));
972 }
973 }
974 }
975
976 void SharedRuntime::restore_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
977 // We always ignore the frame_slots arg and just use the space just below frame pointer
978 // which by this time is free to use
979 switch (ret_type) {
980 case T_FLOAT:
981 __ ldrs(v0, Address(rfp, -wordSize));
982 break;
983 case T_DOUBLE:
984 __ ldrd(v0, Address(rfp, -wordSize));
985 break;
986 case T_VOID: break;
987 default: {
988 __ ldr(r0, Address(rfp, -wordSize));
989 }
990 }
991 }
992 static void save_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
993 RegSet x;
994 for ( int i = first_arg ; i < arg_count ; i++ ) {
995 if (args[i].first()->is_Register()) {
996 x = x + args[i].first()->as_Register();
997 } else if (args[i].first()->is_FloatRegister()) {
998 __ strd(args[i].first()->as_FloatRegister(), Address(__ pre(sp, -2 * wordSize)));
999 }
1000 }
1001 __ push(x, sp);
1002 }
1003
1004 static void restore_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
1005 RegSet x;
1006 for ( int i = first_arg ; i < arg_count ; i++ ) {
1007 if (args[i].first()->is_Register()) {
1008 x = x + args[i].first()->as_Register();
1009 } else {
1010 ;
1011 }
1012 }
1013 __ pop(x, sp);
1014 for ( int i = arg_count - 1 ; i >= first_arg ; i-- ) {
1015 if (args[i].first()->is_Register()) {
1016 ;
1017 } else if (args[i].first()->is_FloatRegister()) {
1018 __ ldrd(args[i].first()->as_FloatRegister(), Address(__ post(sp, 2 * wordSize)));
1019 }
1020 }
1021 }
1022
1023
1024 // Check GC_locker::needs_gc and enter the runtime if it's true. This
1025 // keeps a new JNI critical region from starting until a GC has been
1026 // forced. Save down any oops in registers and describe them in an
1027 // OopMap.
1028 static void check_needs_gc_for_critical_native(MacroAssembler* masm,
1029 int stack_slots,
1030 int total_c_args,
1031 int total_in_args,
1032 int arg_save_area,
1033 OopMapSet* oop_maps,
1034 VMRegPair* in_regs,
1035 BasicType* in_sig_bt) { Unimplemented(); }
1036
1037 // Unpack an array argument into a pointer to the body and the length
1038 // if the array is non-null, otherwise pass 0 for both.
1039 static void unpack_array_argument(MacroAssembler* masm, VMRegPair reg, BasicType in_elem_type, VMRegPair body_arg, VMRegPair length_arg) { Unimplemented(); }
1040
1041
1042 class ComputeMoveOrder: public StackObj {
1043 class MoveOperation: public ResourceObj {
1044 friend class ComputeMoveOrder;
1045 private:
1046 VMRegPair _src;
1047 VMRegPair _dst;
1048 int _src_index;
1049 int _dst_index;
1050 bool _processed;
1051 MoveOperation* _next;
1052 MoveOperation* _prev;
1053
1054 static int get_id(VMRegPair r) { Unimplemented(); return 0; }
1055
1056 public:
1057 MoveOperation(int src_index, VMRegPair src, int dst_index, VMRegPair dst):
1058 _src(src)
1059 , _src_index(src_index)
1060 , _dst(dst)
1061 , _dst_index(dst_index)
1062 , _next(NULL)
1063 , _prev(NULL)
1064 , _processed(false) { Unimplemented(); }
1065
1066 VMRegPair src() const { Unimplemented(); return _src; }
1067 int src_id() const { Unimplemented(); return 0; }
1068 int src_index() const { Unimplemented(); return 0; }
1069 VMRegPair dst() const { Unimplemented(); return _src; }
1070 void set_dst(int i, VMRegPair dst) { Unimplemented(); }
1071 int dst_index() const { Unimplemented(); return 0; }
1072 int dst_id() const { Unimplemented(); return 0; }
1073 MoveOperation* next() const { Unimplemented(); return 0; }
1074 MoveOperation* prev() const { Unimplemented(); return 0; }
1075 void set_processed() { Unimplemented(); }
1076 bool is_processed() const { Unimplemented(); return 0; }
1077
1078 // insert
1079 void break_cycle(VMRegPair temp_register) { Unimplemented(); }
1080
1081 void link(GrowableArray<MoveOperation*>& killer) { Unimplemented(); }
1082 };
1083
1084 private:
1085 GrowableArray<MoveOperation*> edges;
1086
1087 public:
1088 ComputeMoveOrder(int total_in_args, VMRegPair* in_regs, int total_c_args, VMRegPair* out_regs,
1089 BasicType* in_sig_bt, GrowableArray<int>& arg_order, VMRegPair tmp_vmreg) { Unimplemented(); }
1090
1091 // Collected all the move operations
1092 void add_edge(int src_index, VMRegPair src, int dst_index, VMRegPair dst) { Unimplemented(); }
1093
1094 // Walk the edges breaking cycles between moves. The result list
1095 // can be walked in order to produce the proper set of loads
1096 GrowableArray<MoveOperation*>* get_store_order(VMRegPair temp_register) { Unimplemented(); return 0; }
1097 };
1098
1099
1100 static void rt_call(MacroAssembler* masm, address dest, int gpargs, int fpargs, int type) {
1101 CodeBlob *cb = CodeCache::find_blob(dest);
1102 if (cb) {
1103 __ far_call(RuntimeAddress(dest));
1104 } else {
1105 assert((unsigned)gpargs < 256, "eek!");
1106 assert((unsigned)fpargs < 32, "eek!");
1107 __ lea(rscratch1, RuntimeAddress(dest));
1108 __ blr(rscratch1);
1109 __ maybe_isb();
1110 }
1111 }
1112
1113 static void verify_oop_args(MacroAssembler* masm,
1114 methodHandle method,
1115 const BasicType* sig_bt,
1116 const VMRegPair* regs) {
1117 Register temp_reg = r19; // not part of any compiled calling seq
1118 if (VerifyOops) {
1119 for (int i = 0; i < method->size_of_parameters(); i++) {
1120 if (sig_bt[i] == T_OBJECT ||
1121 sig_bt[i] == T_ARRAY) {
1122 VMReg r = regs[i].first();
1123 assert(r->is_valid(), "bad oop arg");
1124 if (r->is_stack()) {
1125 __ ldr(temp_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
1126 __ verify_oop(temp_reg);
1127 } else {
1128 __ verify_oop(r->as_Register());
1129 }
1130 }
1131 }
1132 }
1133 }
1134
1135 static void gen_special_dispatch(MacroAssembler* masm,
1136 methodHandle method,
1137 const BasicType* sig_bt,
1138 const VMRegPair* regs) {
1139 verify_oop_args(masm, method, sig_bt, regs);
1140 vmIntrinsics::ID iid = method->intrinsic_id();
1141
1142 // Now write the args into the outgoing interpreter space
1143 bool has_receiver = false;
1144 Register receiver_reg = noreg;
1145 int member_arg_pos = -1;
1146 Register member_reg = noreg;
1147 int ref_kind = MethodHandles::signature_polymorphic_intrinsic_ref_kind(iid);
1148 if (ref_kind != 0) {
1149 member_arg_pos = method->size_of_parameters() - 1; // trailing MemberName argument
1150 member_reg = r19; // known to be free at this point
1151 has_receiver = MethodHandles::ref_kind_has_receiver(ref_kind);
1152 } else if (iid == vmIntrinsics::_invokeBasic) {
1153 has_receiver = true;
1154 } else {
1155 fatal(err_msg_res("unexpected intrinsic id %d", iid));
1156 }
1157
1158 if (member_reg != noreg) {
1159 // Load the member_arg into register, if necessary.
1160 SharedRuntime::check_member_name_argument_is_last_argument(method, sig_bt, regs);
1161 VMReg r = regs[member_arg_pos].first();
1162 if (r->is_stack()) {
1163 __ ldr(member_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
1164 } else {
1165 // no data motion is needed
1166 member_reg = r->as_Register();
1167 }
1168 }
1169
1170 if (has_receiver) {
1171 // Make sure the receiver is loaded into a register.
1172 assert(method->size_of_parameters() > 0, "oob");
1173 assert(sig_bt[0] == T_OBJECT, "receiver argument must be an object");
1174 VMReg r = regs[0].first();
1175 assert(r->is_valid(), "bad receiver arg");
1176 if (r->is_stack()) {
1177 // Porting note: This assumes that compiled calling conventions always
1178 // pass the receiver oop in a register. If this is not true on some
1179 // platform, pick a temp and load the receiver from stack.
1180 fatal("receiver always in a register");
1181 receiver_reg = r2; // known to be free at this point
1182 __ ldr(receiver_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
1183 } else {
1184 // no data motion is needed
1185 receiver_reg = r->as_Register();
1186 }
1187 }
1188
1189 // Figure out which address we are really jumping to:
1190 MethodHandles::generate_method_handle_dispatch(masm, iid,
1191 receiver_reg, member_reg, /*for_compiler_entry:*/ true);
1192 }
1193
1194 // ---------------------------------------------------------------------------
1195 // Generate a native wrapper for a given method. The method takes arguments
1196 // in the Java compiled code convention, marshals them to the native
1197 // convention (handlizes oops, etc), transitions to native, makes the call,
1198 // returns to java state (possibly blocking), unhandlizes any result and
1199 // returns.
1200 //
1201 // Critical native functions are a shorthand for the use of
1202 // GetPrimtiveArrayCritical and disallow the use of any other JNI
1203 // functions. The wrapper is expected to unpack the arguments before
1204 // passing them to the callee and perform checks before and after the
1205 // native call to ensure that they GC_locker
1206 // lock_critical/unlock_critical semantics are followed. Some other
1207 // parts of JNI setup are skipped like the tear down of the JNI handle
1208 // block and the check for pending exceptions it's impossible for them
1209 // to be thrown.
1210 //
1211 // They are roughly structured like this:
1212 // if (GC_locker::needs_gc())
1213 // SharedRuntime::block_for_jni_critical();
1214 // tranistion to thread_in_native
1215 // unpack arrray arguments and call native entry point
1216 // check for safepoint in progress
1217 // check if any thread suspend flags are set
1218 // call into JVM and possible unlock the JNI critical
1219 // if a GC was suppressed while in the critical native.
1220 // transition back to thread_in_Java
1221 // return to caller
1222 //
1223 nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
1224 methodHandle method,
1225 int compile_id,
1226 BasicType* in_sig_bt,
1227 VMRegPair* in_regs,
1228 BasicType ret_type) {
1229 if (method->is_method_handle_intrinsic()) {
1230 vmIntrinsics::ID iid = method->intrinsic_id();
1231 intptr_t start = (intptr_t)__ pc();
1232 int vep_offset = ((intptr_t)__ pc()) - start;
1233
1234 // First instruction must be a nop as it may need to be patched on deoptimisation
1235 __ nop();
1236 gen_special_dispatch(masm,
1237 method,
1238 in_sig_bt,
1239 in_regs);
1240 int frame_complete = ((intptr_t)__ pc()) - start; // not complete, period
1241 __ flush();
1242 int stack_slots = SharedRuntime::out_preserve_stack_slots(); // no out slots at all, actually
1243 return nmethod::new_native_nmethod(method,
1244 compile_id,
1245 masm->code(),
1246 vep_offset,
1247 frame_complete,
1248 stack_slots / VMRegImpl::slots_per_word,
1249 in_ByteSize(-1),
1250 in_ByteSize(-1),
1251 (OopMapSet*)NULL);
1252 }
1253 bool is_critical_native = true;
1254 address native_func = method->critical_native_function();
1255 if (native_func == NULL) {
1256 native_func = method->native_function();
1257 is_critical_native = false;
1258 }
1259 assert(native_func != NULL, "must have function");
1260
1261 // An OopMap for lock (and class if static)
1262 OopMapSet *oop_maps = new OopMapSet();
1263 intptr_t start = (intptr_t)__ pc();
1264
1265 // We have received a description of where all the java arg are located
1266 // on entry to the wrapper. We need to convert these args to where
1267 // the jni function will expect them. To figure out where they go
1268 // we convert the java signature to a C signature by inserting
1269 // the hidden arguments as arg[0] and possibly arg[1] (static method)
1270
1271 const int total_in_args = method->size_of_parameters();
1272 int total_c_args = total_in_args;
1273 if (!is_critical_native) {
1274 total_c_args += 1;
1275 if (method->is_static()) {
1276 total_c_args++;
1277 }
1278 } else {
1279 for (int i = 0; i < total_in_args; i++) {
1280 if (in_sig_bt[i] == T_ARRAY) {
1281 total_c_args++;
1282 }
1283 }
1284 }
1285
1286 BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_c_args);
1287 VMRegPair* out_regs = NEW_RESOURCE_ARRAY(VMRegPair, total_c_args);
1288 BasicType* in_elem_bt = NULL;
1289
1290 int argc = 0;
1291 if (!is_critical_native) {
1292 out_sig_bt[argc++] = T_ADDRESS;
1293 if (method->is_static()) {
1294 out_sig_bt[argc++] = T_OBJECT;
1295 }
1296
1297 for (int i = 0; i < total_in_args ; i++ ) {
1298 out_sig_bt[argc++] = in_sig_bt[i];
1299 }
1300 } else {
1301 Thread* THREAD = Thread::current();
1302 in_elem_bt = NEW_RESOURCE_ARRAY(BasicType, total_in_args);
1303 SignatureStream ss(method->signature());
1304 for (int i = 0; i < total_in_args ; i++ ) {
1305 if (in_sig_bt[i] == T_ARRAY) {
1306 // Arrays are passed as int, elem* pair
1307 out_sig_bt[argc++] = T_INT;
1308 out_sig_bt[argc++] = T_ADDRESS;
1309 Symbol* atype = ss.as_symbol(CHECK_NULL);
1310 const char* at = atype->as_C_string();
1311 if (strlen(at) == 2) {
1312 assert(at[0] == '[', "must be");
1313 switch (at[1]) {
1314 case 'B': in_elem_bt[i] = T_BYTE; break;
1315 case 'C': in_elem_bt[i] = T_CHAR; break;
1316 case 'D': in_elem_bt[i] = T_DOUBLE; break;
1317 case 'F': in_elem_bt[i] = T_FLOAT; break;
1318 case 'I': in_elem_bt[i] = T_INT; break;
1319 case 'J': in_elem_bt[i] = T_LONG; break;
1320 case 'S': in_elem_bt[i] = T_SHORT; break;
1321 case 'Z': in_elem_bt[i] = T_BOOLEAN; break;
1322 default: ShouldNotReachHere();
1323 }
1324 }
1325 } else {
1326 out_sig_bt[argc++] = in_sig_bt[i];
1327 in_elem_bt[i] = T_VOID;
1328 }
1329 if (in_sig_bt[i] != T_VOID) {
1330 assert(in_sig_bt[i] == ss.type(), "must match");
1331 ss.next();
1332 }
1333 }
1334 }
1335
1336 // Now figure out where the args must be stored and how much stack space
1337 // they require.
1338 int out_arg_slots;
1339 out_arg_slots = c_calling_convention(out_sig_bt, out_regs, NULL, total_c_args);
1340
1341 // Compute framesize for the wrapper. We need to handlize all oops in
1342 // incoming registers
1343
1344 // Calculate the total number of stack slots we will need.
1345
1346 // First count the abi requirement plus all of the outgoing args
1347 int stack_slots = SharedRuntime::out_preserve_stack_slots() + out_arg_slots;
1348
1349 // Now the space for the inbound oop handle area
1350 int total_save_slots = 8 * VMRegImpl::slots_per_word; // 8 arguments passed in registers
1351 if (is_critical_native) {
1352 // Critical natives may have to call out so they need a save area
1353 // for register arguments.
1354 int double_slots = 0;
1355 int single_slots = 0;
1356 for ( int i = 0; i < total_in_args; i++) {
1357 if (in_regs[i].first()->is_Register()) {
1358 const Register reg = in_regs[i].first()->as_Register();
1359 switch (in_sig_bt[i]) {
1360 case T_BOOLEAN:
1361 case T_BYTE:
1362 case T_SHORT:
1363 case T_CHAR:
1364 case T_INT: single_slots++; break;
1365 case T_ARRAY: // specific to LP64 (7145024)
1366 case T_LONG: double_slots++; break;
1367 default: ShouldNotReachHere();
1368 }
1369 } else if (in_regs[i].first()->is_FloatRegister()) {
1370 ShouldNotReachHere();
1371 }
1372 }
1373 total_save_slots = double_slots * 2 + single_slots;
1374 // align the save area
1375 if (double_slots != 0) {
1376 stack_slots = round_to(stack_slots, 2);
1377 }
1378 }
1379
1380 int oop_handle_offset = stack_slots;
1381 stack_slots += total_save_slots;
1382
1383 // Now any space we need for handlizing a klass if static method
1384
1385 int klass_slot_offset = 0;
1386 int klass_offset = -1;
1387 int lock_slot_offset = 0;
1388 bool is_static = false;
1389
1390 if (method->is_static()) {
1391 klass_slot_offset = stack_slots;
1392 stack_slots += VMRegImpl::slots_per_word;
1393 klass_offset = klass_slot_offset * VMRegImpl::stack_slot_size;
1394 is_static = true;
1395 }
1396
1397 // Plus a lock if needed
1398
1399 if (method->is_synchronized()) {
1400 lock_slot_offset = stack_slots;
1401 stack_slots += VMRegImpl::slots_per_word;
1402 }
1403
1404 // Now a place (+2) to save return values or temp during shuffling
1405 // + 4 for return address (which we own) and saved rfp
1406 stack_slots += 6;
1407
1408 // Ok The space we have allocated will look like:
1409 //
1410 //
1411 // FP-> | |
1412 // |---------------------|
1413 // | 2 slots for moves |
1414 // |---------------------|
1415 // | lock box (if sync) |
1416 // |---------------------| <- lock_slot_offset
1417 // | klass (if static) |
1418 // |---------------------| <- klass_slot_offset
1419 // | oopHandle area |
1420 // |---------------------| <- oop_handle_offset (8 java arg registers)
1421 // | outbound memory |
1422 // | based arguments |
1423 // | |
1424 // |---------------------|
1425 // | |
1426 // SP-> | out_preserved_slots |
1427 //
1428 //
1429
1430
1431 // Now compute actual number of stack words we need rounding to make
1432 // stack properly aligned.
1433 stack_slots = round_to(stack_slots, StackAlignmentInSlots);
1434
1435 int stack_size = stack_slots * VMRegImpl::stack_slot_size;
1436
1437 // First thing make an ic check to see if we should even be here
1438
1439 // We are free to use all registers as temps without saving them and
1440 // restoring them except rfp. rfp is the only callee save register
1441 // as far as the interpreter and the compiler(s) are concerned.
1442
1443
1444 const Register ic_reg = rscratch2;
1445 const Register receiver = j_rarg0;
1446
1447 Label hit;
1448 Label exception_pending;
1449
1450 assert_different_registers(ic_reg, receiver, rscratch1);
1451 __ verify_oop(receiver);
1452 __ cmp_klass(receiver, ic_reg, rscratch1);
1453 __ br(Assembler::EQ, hit);
1454
1455 __ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
1456
1457 // Verified entry point must be aligned
1458 __ align(8);
1459
1460 __ bind(hit);
1461
1462 int vep_offset = ((intptr_t)__ pc()) - start;
1463
1464 // If we have to make this method not-entrant we'll overwrite its
1465 // first instruction with a jump. For this action to be legal we
1466 // must ensure that this first instruction is a B, BL, NOP, BKPT,
1467 // SVC, HVC, or SMC. Make it a NOP.
1468 __ nop();
1469
1470 // Generate stack overflow check
1471 if (UseStackBanging) {
1472 __ bang_stack_with_offset(StackShadowPages*os::vm_page_size());
1473 } else {
1474 Unimplemented();
1475 }
1476
1477 // Generate a new frame for the wrapper.
1478 __ enter();
1479 // -2 because return address is already present and so is saved rfp
1480 __ sub(sp, sp, stack_size - 2*wordSize);
1481
1482 // Frame is now completed as far as size and linkage.
1483 int frame_complete = ((intptr_t)__ pc()) - start;
1484
1485 // We use r20 as the oop handle for the receiver/klass
1486 // It is callee save so it survives the call to native
1487
1488 const Register oop_handle_reg = r20;
1489
1490 if (is_critical_native) {
1491 check_needs_gc_for_critical_native(masm, stack_slots, total_c_args, total_in_args,
1492 oop_handle_offset, oop_maps, in_regs, in_sig_bt);
1493 }
1494
1495 //
1496 // We immediately shuffle the arguments so that any vm call we have to
1497 // make from here on out (sync slow path, jvmti, etc.) we will have
1498 // captured the oops from our caller and have a valid oopMap for
1499 // them.
1500
1501 // -----------------
1502 // The Grand Shuffle
1503
1504 // The Java calling convention is either equal (linux) or denser (win64) than the
1505 // c calling convention. However the because of the jni_env argument the c calling
1506 // convention always has at least one more (and two for static) arguments than Java.
1507 // Therefore if we move the args from java -> c backwards then we will never have
1508 // a register->register conflict and we don't have to build a dependency graph
1509 // and figure out how to break any cycles.
1510 //
1511
1512 // Record esp-based slot for receiver on stack for non-static methods
1513 int receiver_offset = -1;
1514
1515 // This is a trick. We double the stack slots so we can claim
1516 // the oops in the caller's frame. Since we are sure to have
1517 // more args than the caller doubling is enough to make
1518 // sure we can capture all the incoming oop args from the
1519 // caller.
1520 //
1521 OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);
1522
1523 // Mark location of rfp (someday)
1524 // map->set_callee_saved(VMRegImpl::stack2reg( stack_slots - 2), stack_slots * 2, 0, vmreg(rfp));
1525
1526
1527 int float_args = 0;
1528 int int_args = 0;
1529
1530 #ifdef ASSERT
1531 bool reg_destroyed[RegisterImpl::number_of_registers];
1532 bool freg_destroyed[FloatRegisterImpl::number_of_registers];
1533 for ( int r = 0 ; r < RegisterImpl::number_of_registers ; r++ ) {
1534 reg_destroyed[r] = false;
1535 }
1536 for ( int f = 0 ; f < FloatRegisterImpl::number_of_registers ; f++ ) {
1537 freg_destroyed[f] = false;
1538 }
1539
1540 #endif /* ASSERT */
1541
1542 // This may iterate in two different directions depending on the
1543 // kind of native it is. The reason is that for regular JNI natives
1544 // the incoming and outgoing registers are offset upwards and for
1545 // critical natives they are offset down.
1546 GrowableArray<int> arg_order(2 * total_in_args);
1547 VMRegPair tmp_vmreg;
1548 tmp_vmreg.set1(r19->as_VMReg());
1549
1550 if (!is_critical_native) {
1551 for (int i = total_in_args - 1, c_arg = total_c_args - 1; i >= 0; i--, c_arg--) {
1552 arg_order.push(i);
1553 arg_order.push(c_arg);
1554 }
1555 } else {
1556 // Compute a valid move order, using tmp_vmreg to break any cycles
1557 ComputeMoveOrder cmo(total_in_args, in_regs, total_c_args, out_regs, in_sig_bt, arg_order, tmp_vmreg);
1558 }
1559
1560 int temploc = -1;
1561 for (int ai = 0; ai < arg_order.length(); ai += 2) {
1562 int i = arg_order.at(ai);
1563 int c_arg = arg_order.at(ai + 1);
1564 __ block_comment(err_msg("move %d -> %d", i, c_arg));
1565 if (c_arg == -1) {
1566 assert(is_critical_native, "should only be required for critical natives");
1567 // This arg needs to be moved to a temporary
1568 __ mov(tmp_vmreg.first()->as_Register(), in_regs[i].first()->as_Register());
1569 in_regs[i] = tmp_vmreg;
1570 temploc = i;
1571 continue;
1572 } else if (i == -1) {
1573 assert(is_critical_native, "should only be required for critical natives");
1574 // Read from the temporary location
1575 assert(temploc != -1, "must be valid");
1576 i = temploc;
1577 temploc = -1;
1578 }
1579 #ifdef ASSERT
1580 if (in_regs[i].first()->is_Register()) {
1581 assert(!reg_destroyed[in_regs[i].first()->as_Register()->encoding()], "destroyed reg!");
1582 } else if (in_regs[i].first()->is_FloatRegister()) {
1583 assert(!freg_destroyed[in_regs[i].first()->as_FloatRegister()->encoding()], "destroyed reg!");
1584 }
1585 if (out_regs[c_arg].first()->is_Register()) {
1586 reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
1587 } else if (out_regs[c_arg].first()->is_FloatRegister()) {
1588 freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding()] = true;
1589 }
1590 #endif /* ASSERT */
1591 switch (in_sig_bt[i]) {
1592 case T_ARRAY:
1593 if (is_critical_native) {
1594 unpack_array_argument(masm, in_regs[i], in_elem_bt[i], out_regs[c_arg + 1], out_regs[c_arg]);
1595 c_arg++;
1596 #ifdef ASSERT
1597 if (out_regs[c_arg].first()->is_Register()) {
1598 reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
1599 } else if (out_regs[c_arg].first()->is_FloatRegister()) {
1600 freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding()] = true;
1601 }
1602 #endif
1603 int_args++;
1604 break;
1605 }
1606 case T_OBJECT:
1607 assert(!is_critical_native, "no oop arguments");
1608 object_move(masm, map, oop_handle_offset, stack_slots, in_regs[i], out_regs[c_arg],
1609 ((i == 0) && (!is_static)),
1610 &receiver_offset);
1611 int_args++;
1612 break;
1613 case T_VOID:
1614 break;
1615
1616 case T_FLOAT:
1617 float_move(masm, in_regs[i], out_regs[c_arg]);
1618 float_args++;
1619 break;
1620
1621 case T_DOUBLE:
1622 assert( i + 1 < total_in_args &&
1623 in_sig_bt[i + 1] == T_VOID &&
1624 out_sig_bt[c_arg+1] == T_VOID, "bad arg list");
1625 double_move(masm, in_regs[i], out_regs[c_arg]);
1626 float_args++;
1627 break;
1628
1629 case T_LONG :
1630 long_move(masm, in_regs[i], out_regs[c_arg]);
1631 int_args++;
1632 break;
1633
1634 case T_ADDRESS: assert(false, "found T_ADDRESS in java args");
1635
1636 default:
1637 move32_64(masm, in_regs[i], out_regs[c_arg]);
1638 int_args++;
1639 }
1640 }
1641
1642 // point c_arg at the first arg that is already loaded in case we
1643 // need to spill before we call out
1644 int c_arg = total_c_args - total_in_args;
1645
1646 // Pre-load a static method's oop into c_rarg1.
1647 if (method->is_static() && !is_critical_native) {
1648
1649 // load oop into a register
1650 __ movoop(c_rarg1,
1651 JNIHandles::make_local(method->method_holder()->java_mirror()),
1652 /*immediate*/true);
1653
1654 // Now handlize the static class mirror it's known not-null.
1655 __ str(c_rarg1, Address(sp, klass_offset));
1656 map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));
1657
1658 // Now get the handle
1659 __ lea(c_rarg1, Address(sp, klass_offset));
1660 // and protect the arg if we must spill
1661 c_arg--;
1662 }
1663
1664 // Change state to native (we save the return address in the thread, since it might not
1665 // be pushed on the stack when we do a stack traversal).
1666 // We use the same pc/oopMap repeatedly when we call out
1667
1668 Label native_return;
1669 __ set_last_Java_frame(sp, noreg, native_return, rscratch1);
1670
1671 Label dtrace_method_entry, dtrace_method_entry_done;
1672 {
1673 unsigned long offset;
1674 __ adrp(rscratch1, ExternalAddress((address)&DTraceMethodProbes), offset);
1675 __ ldrb(rscratch1, Address(rscratch1, offset));
1676 __ cbnzw(rscratch1, dtrace_method_entry);
1677 __ bind(dtrace_method_entry_done);
1678 }
1679
1680 // RedefineClasses() tracing support for obsolete method entry
1681 if (RC_TRACE_IN_RANGE(0x00001000, 0x00002000)) {
1682 // protect the args we've loaded
1683 save_args(masm, total_c_args, c_arg, out_regs);
1684 __ mov_metadata(c_rarg1, method());
1685 __ call_VM_leaf(
1686 CAST_FROM_FN_PTR(address, SharedRuntime::rc_trace_method_entry),
1687 rthread, c_rarg1);
1688 restore_args(masm, total_c_args, c_arg, out_regs);
1689 }
1690
1691 // Lock a synchronized method
1692
1693 // Register definitions used by locking and unlocking
1694
1695 const Register swap_reg = r0;
1696 const Register obj_reg = r19; // Will contain the oop
1697 const Register lock_reg = r13; // Address of compiler lock object (BasicLock)
1698 const Register old_hdr = r13; // value of old header at unlock time
1699 const Register tmp = lr;
1700
1701 Label slow_path_lock;
1702 Label lock_done;
1703
1704 if (method->is_synchronized()) {
1705 assert(!is_critical_native, "unhandled");
1706
1707 const int mark_word_offset = BasicLock::displaced_header_offset_in_bytes();
1708
1709 // Get the handle (the 2nd argument)
1710 __ mov(oop_handle_reg, c_rarg1);
1711
1712 // Get address of the box
1713
1714 __ lea(lock_reg, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
1715
1716 // Load the oop from the handle
1717 __ ldr(obj_reg, Address(oop_handle_reg, 0));
1718
1719 if (UseBiasedLocking) {
1720 __ biased_locking_enter(lock_reg, obj_reg, swap_reg, tmp, false, lock_done, &slow_path_lock);
1721 }
1722
1723 // Load (object->mark() | 1) into swap_reg %r0
1724 __ ldr(rscratch1, Address(obj_reg, 0));
1725 __ orr(swap_reg, rscratch1, 1);
1726
1727 // Save (object->mark() | 1) into BasicLock's displaced header
1728 __ str(swap_reg, Address(lock_reg, mark_word_offset));
1729
1730 // src -> dest iff dest == r0 else r0 <- dest
1731 { Label here;
1732 __ cmpxchgptr(r0, lock_reg, obj_reg, rscratch1, lock_done, /*fallthrough*/NULL);
1733 }
1734
1735 // Hmm should this move to the slow path code area???
1736
1737 // Test if the oopMark is an obvious stack pointer, i.e.,
1738 // 1) (mark & 3) == 0, and
1739 // 2) sp <= mark < mark + os::pagesize()
1740 // These 3 tests can be done by evaluating the following
1741 // expression: ((mark - sp) & (3 - os::vm_page_size())),
1742 // assuming both stack pointer and pagesize have their
1743 // least significant 2 bits clear.
1744 // NOTE: the oopMark is in swap_reg %r0 as the result of cmpxchg
1745
1746 __ sub(swap_reg, sp, swap_reg);
1747 __ neg(swap_reg, swap_reg);
1748 __ ands(swap_reg, swap_reg, 3 - os::vm_page_size());
1749
1750 // Save the test result, for recursive case, the result is zero
1751 __ str(swap_reg, Address(lock_reg, mark_word_offset));
1752 __ br(Assembler::NE, slow_path_lock);
1753
1754 // Slow path will re-enter here
1755
1756 __ bind(lock_done);
1757 }
1758
1759
1760 // Finally just about ready to make the JNI call
1761
1762 // get JNIEnv* which is first argument to native
1763 if (!is_critical_native) {
1764 __ lea(c_rarg0, Address(rthread, in_bytes(JavaThread::jni_environment_offset())));
1765 }
1766
1767 // Now set thread in native
1768 __ mov(rscratch1, _thread_in_native);
1769 __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1770 __ stlrw(rscratch1, rscratch2);
1771
1772 {
1773 int return_type = 0;
1774 switch (ret_type) {
1775 case T_VOID: break;
1776 return_type = 0; break;
1777 case T_CHAR:
1778 case T_BYTE:
1779 case T_SHORT:
1780 case T_INT:
1781 case T_BOOLEAN:
1782 case T_LONG:
1783 return_type = 1; break;
1784 case T_ARRAY:
1785 case T_OBJECT:
1786 return_type = 1; break;
1787 case T_FLOAT:
1788 return_type = 2; break;
1789 case T_DOUBLE:
1790 return_type = 3; break;
1791 default:
1792 ShouldNotReachHere();
1793 }
1794 rt_call(masm, native_func,
1795 int_args + 2, // AArch64 passes up to 8 args in int registers
1796 float_args, // and up to 8 float args
1797 return_type);
1798 }
1799
1800 __ bind(native_return);
1801
1802 intptr_t return_pc = (intptr_t) __ pc();
1803 oop_maps->add_gc_map(return_pc - start, map);
1804
1805 // Unpack native results.
1806 switch (ret_type) {
1807 case T_BOOLEAN: __ c2bool(r0); break;
1808 case T_CHAR : __ ubfx(r0, r0, 0, 16); break;
1809 case T_BYTE : __ sbfx(r0, r0, 0, 8); break;
1810 case T_SHORT : __ sbfx(r0, r0, 0, 16); break;
1811 case T_INT : __ sbfx(r0, r0, 0, 32); break;
1812 case T_DOUBLE :
1813 case T_FLOAT :
1814 // Result is in v0 we'll save as needed
1815 break;
1816 case T_ARRAY: // Really a handle
1817 case T_OBJECT: // Really a handle
1818 break; // can't de-handlize until after safepoint check
1819 case T_VOID: break;
1820 case T_LONG: break;
1821 default : ShouldNotReachHere();
1822 }
1823
1824 // Switch thread to "native transition" state before reading the synchronization state.
1825 // This additional state is necessary because reading and testing the synchronization
1826 // state is not atomic w.r.t. GC, as this scenario demonstrates:
1827 // Java thread A, in _thread_in_native state, loads _not_synchronized and is preempted.
1828 // VM thread changes sync state to synchronizing and suspends threads for GC.
1829 // Thread A is resumed to finish this native method, but doesn't block here since it
1830 // didn't see any synchronization is progress, and escapes.
1831 __ mov(rscratch1, _thread_in_native_trans);
1832
1833 if(os::is_MP()) {
1834 if (UseMembar) {
1835 __ strw(rscratch1, Address(rthread, JavaThread::thread_state_offset()));
1836
1837 // Force this write out before the read below
1838 __ dmb(Assembler::SY);
1839 } else {
1840 __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1841 __ stlrw(rscratch1, rscratch2);
1842
1843 // Write serialization page so VM thread can do a pseudo remote membar.
1844 // We use the current thread pointer to calculate a thread specific
1845 // offset to write to within the page. This minimizes bus traffic
1846 // due to cache line collision.
1847 __ serialize_memory(rthread, r2);
1848 }
1849 } else {
1850 __ strw(rscratch1, Address(rthread, JavaThread::thread_state_offset()));
1851 }
1852
1853 // check for safepoint operation in progress and/or pending suspend requests
1854 Label safepoint_in_progress, safepoint_in_progress_done;
1855 {
1856 assert(SafepointSynchronize::_not_synchronized == 0, "fix this code");
1857 unsigned long offset;
1858 __ adrp(rscratch1,
1859 ExternalAddress((address)SafepointSynchronize::address_of_state()),
1860 offset);
1861 __ ldrw(rscratch1, Address(rscratch1, offset));
1862 __ cbnzw(rscratch1, safepoint_in_progress);
1863 __ ldrw(rscratch1, Address(rthread, JavaThread::suspend_flags_offset()));
1864 __ cbnzw(rscratch1, safepoint_in_progress);
1865 __ bind(safepoint_in_progress_done);
1866 }
1867
1868 // change thread state
1869 Label after_transition;
1870 __ mov(rscratch1, _thread_in_Java);
1871 __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1872 __ stlrw(rscratch1, rscratch2);
1873 __ bind(after_transition);
1874
1875 Label reguard;
1876 Label reguard_done;
1877 __ ldrb(rscratch1, Address(rthread, JavaThread::stack_guard_state_offset()));
1878 __ cmpw(rscratch1, JavaThread::stack_guard_yellow_disabled);
1879 __ br(Assembler::EQ, reguard);
1880 __ bind(reguard_done);
1881
1882 // native result if any is live
1883
1884 // Unlock
1885 Label unlock_done;
1886 Label slow_path_unlock;
1887 if (method->is_synchronized()) {
1888
1889 // Get locked oop from the handle we passed to jni
1890 __ ldr(obj_reg, Address(oop_handle_reg, 0));
1891
1892 Label done;
1893
1894 if (UseBiasedLocking) {
1895 __ biased_locking_exit(obj_reg, old_hdr, done);
1896 }
1897
1898 // Simple recursive lock?
1899
1900 __ ldr(rscratch1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
1901 __ cbz(rscratch1, done);
1902
1903 // Must save r0 if if it is live now because cmpxchg must use it
1904 if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
1905 save_native_result(masm, ret_type, stack_slots);
1906 }
1907
1908
1909 // get address of the stack lock
1910 __ lea(r0, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
1911 // get old displaced header
1912 __ ldr(old_hdr, Address(r0, 0));
1913
1914 // Atomic swap old header if oop still contains the stack lock
1915 Label succeed;
1916 __ cmpxchgptr(r0, old_hdr, obj_reg, rscratch1, succeed, &slow_path_unlock);
1917 __ bind(succeed);
1918
1919 // slow path re-enters here
1920 __ bind(unlock_done);
1921 if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
1922 restore_native_result(masm, ret_type, stack_slots);
1923 }
1924
1925 __ bind(done);
1926 }
1927
1928 Label dtrace_method_exit, dtrace_method_exit_done;
1929 {
1930 unsigned long offset;
1931 __ adrp(rscratch1, ExternalAddress((address)&DTraceMethodProbes), offset);
1932 __ ldrb(rscratch1, Address(rscratch1, offset));
1933 __ cbnzw(rscratch1, dtrace_method_exit);
1934 __ bind(dtrace_method_exit_done);
1935 }
1936
1937 __ reset_last_Java_frame(false);
1938
1939 // Unbox oop result, e.g. JNIHandles::resolve result.
1940 if (ret_type == T_OBJECT || ret_type == T_ARRAY) {
1941 Label done, not_weak;
1942 __ cbz(r0, done); // Use NULL as-is.
1943 STATIC_ASSERT(JNIHandles::weak_tag_mask == 1u);
1944 __ tbz(r0, 0, not_weak); // Test for jweak tag.
1945 // Resolve jweak.
1946 __ ldr(r0, Address(r0, -JNIHandles::weak_tag_value));
1947 __ verify_oop(r0);
1948 #if INCLUDE_ALL_GCS
1949 if (UseG1GC) {
1950 __ g1_write_barrier_pre(noreg /* obj */,
1951 r0 /* pre_val */,
1952 rthread /* thread */,
1953 rscratch2 /* tmp */,
1954 true /* tosca_live */,
1955 true /* expand_call */);
1956 }
1957 #endif // INCLUDE_ALL_GCS
1958 __ b(done);
1959 __ bind(not_weak);
1960 // Resolve (untagged) jobject.
1961 __ ldr(r0, Address(r0, 0));
1962 __ verify_oop(r0);
1963 __ bind(done);
1964 }
1965
1966 if (!is_critical_native) {
1967 // reset handle block
1968 __ ldr(r2, Address(rthread, JavaThread::active_handles_offset()));
1969 __ str(zr, Address(r2, JNIHandleBlock::top_offset_in_bytes()));
1970 }
1971
1972 __ leave();
1973
1974 if (!is_critical_native) {
1975 // Any exception pending?
1976 __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1977 __ cbnz(rscratch1, exception_pending);
1978 }
1979
1980 // We're done
1981 __ ret(lr);
1982
1983 // Unexpected paths are out of line and go here
1984
1985 if (!is_critical_native) {
1986 // forward the exception
1987 __ bind(exception_pending);
1988
1989 // and forward the exception
1990 __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
1991 }
1992
1993 // Slow path locking & unlocking
1994 if (method->is_synchronized()) {
1995
1996 __ block_comment("Slow path lock {");
1997 __ bind(slow_path_lock);
1998
1999 // has last_Java_frame setup. No exceptions so do vanilla call not call_VM
2000 // args are (oop obj, BasicLock* lock, JavaThread* thread)
2001
2002 // protect the args we've loaded
2003 save_args(masm, total_c_args, c_arg, out_regs);
2004
2005 __ mov(c_rarg0, obj_reg);
2006 __ mov(c_rarg1, lock_reg);
2007 __ mov(c_rarg2, rthread);
2008
2009 // Not a leaf but we have last_Java_frame setup as we want
2010 __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C), 3);
2011 restore_args(masm, total_c_args, c_arg, out_regs);
2012
2013 #ifdef ASSERT
2014 { Label L;
2015 __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2016 __ cbz(rscratch1, L);
2017 __ stop("no pending exception allowed on exit from monitorenter");
2018 __ bind(L);
2019 }
2020 #endif
2021 __ b(lock_done);
2022
2023 __ block_comment("} Slow path lock");
2024
2025 __ block_comment("Slow path unlock {");
2026 __ bind(slow_path_unlock);
2027
2028 // If we haven't already saved the native result we must save it now as xmm registers
2029 // are still exposed.
2030
2031 if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
2032 save_native_result(masm, ret_type, stack_slots);
2033 }
2034
2035 __ lea(c_rarg1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
2036 __ mov(c_rarg0, obj_reg);
2037
2038 // Save pending exception around call to VM (which contains an EXCEPTION_MARK)
2039 // NOTE that obj_reg == r19 currently
2040 __ ldr(r19, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2041 __ str(zr, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2042
2043 rt_call(masm, CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C), 2, 0, 1);
2044
2045 #ifdef ASSERT
2046 {
2047 Label L;
2048 __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2049 __ cbz(rscratch1, L);
2050 __ stop("no pending exception allowed on exit complete_monitor_unlocking_C");
2051 __ bind(L);
2052 }
2053 #endif /* ASSERT */
2054
2055 __ str(r19, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2056
2057 if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
2058 restore_native_result(masm, ret_type, stack_slots);
2059 }
2060 __ b(unlock_done);
2061
2062 __ block_comment("} Slow path unlock");
2063
2064 } // synchronized
2065
2066 // SLOW PATH Reguard the stack if needed
2067
2068 __ bind(reguard);
2069 save_native_result(masm, ret_type, stack_slots);
2070 rt_call(masm, CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages), 0, 0, 0);
2071 restore_native_result(masm, ret_type, stack_slots);
2072 // and continue
2073 __ b(reguard_done);
2074
2075 // SLOW PATH safepoint
2076 {
2077 __ block_comment("safepoint {");
2078 __ bind(safepoint_in_progress);
2079
2080 // Don't use call_VM as it will see a possible pending exception and forward it
2081 // and never return here preventing us from clearing _last_native_pc down below.
2082 //
2083 save_native_result(masm, ret_type, stack_slots);
2084 __ mov(c_rarg0, rthread);
2085 #ifndef PRODUCT
2086 assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
2087 #endif
2088 if (!is_critical_native) {
2089 __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans)));
2090 } else {
2091 __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans_and_transition)));
2092 }
2093 __ blr(rscratch1);
2094 __ maybe_isb();
2095 // Restore any method result value
2096 restore_native_result(masm, ret_type, stack_slots);
2097
2098 if (is_critical_native) {
2099 // The call above performed the transition to thread_in_Java so
2100 // skip the transition logic above.
2101 __ b(after_transition);
2102 }
2103
2104 __ b(safepoint_in_progress_done);
2105 __ block_comment("} safepoint");
2106 }
2107
2108 // SLOW PATH dtrace support
2109 {
2110 __ block_comment("dtrace entry {");
2111 __ bind(dtrace_method_entry);
2112
2113 // We have all of the arguments setup at this point. We must not touch any register
2114 // argument registers at this point (what if we save/restore them there are no oop?
2115
2116 save_args(masm, total_c_args, c_arg, out_regs);
2117 __ mov_metadata(c_rarg1, method());
2118 __ call_VM_leaf(
2119 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),
2120 rthread, c_rarg1);
2121 restore_args(masm, total_c_args, c_arg, out_regs);
2122 __ b(dtrace_method_entry_done);
2123 __ block_comment("} dtrace entry");
2124 }
2125
2126 {
2127 __ block_comment("dtrace exit {");
2128 __ bind(dtrace_method_exit);
2129 save_native_result(masm, ret_type, stack_slots);
2130 __ mov_metadata(c_rarg1, method());
2131 __ call_VM_leaf(
2132 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit),
2133 rthread, c_rarg1);
2134 restore_native_result(masm, ret_type, stack_slots);
2135 __ b(dtrace_method_exit_done);
2136 __ block_comment("} dtrace exit");
2137 }
2138
2139
2140 __ flush();
2141
2142 nmethod *nm = nmethod::new_native_nmethod(method,
2143 compile_id,
2144 masm->code(),
2145 vep_offset,
2146 frame_complete,
2147 stack_slots / VMRegImpl::slots_per_word,
2148 (is_static ? in_ByteSize(klass_offset) : in_ByteSize(receiver_offset)),
2149 in_ByteSize(lock_slot_offset*VMRegImpl::stack_slot_size),
2150 oop_maps);
2151
2152 if (is_critical_native) {
2153 nm->set_lazy_critical_native(true);
2154 }
2155
2156 return nm;
2157
2158 }
2159
2160
2161 #ifdef HAVE_DTRACE_H
2162 // ---------------------------------------------------------------------------
2163 // Generate a dtrace nmethod for a given signature. The method takes arguments
2164 // in the Java compiled code convention, marshals them to the native
2165 // abi and then leaves nops at the position you would expect to call a native
2166 // function. When the probe is enabled the nops are replaced with a trap
2167 // instruction that dtrace inserts and the trace will cause a notification
2168 // to dtrace.
2169 //
2170 // The probes are only able to take primitive types and java/lang/String as
2171 // arguments. No other java types are allowed. Strings are converted to utf8
2172 // strings so that from dtrace point of view java strings are converted to C
2173 // strings. There is an arbitrary fixed limit on the total space that a method
2174 // can use for converting the strings. (256 chars per string in the signature).
2175 // So any java string larger then this is truncated.
2176
2177 static int fp_offset[ConcreteRegisterImpl::number_of_registers] = { 0 };
2178 static bool offsets_initialized = false;
2179
2180
2181 nmethod *SharedRuntime::generate_dtrace_nmethod(MacroAssembler *masm,
2182 methodHandle method) { Unimplemented(); return 0; }
2183
2184 #endif // HAVE_DTRACE_H
2185
2186 // this function returns the adjust size (in number of words) to a c2i adapter
2187 // activation for use during deoptimization
2188 int Deoptimization::last_frame_adjust(int callee_parameters, int callee_locals) {
2189 assert(callee_locals >= callee_parameters,
2190 "test and remove; got more parms than locals");
2191 if (callee_locals < callee_parameters)
2192 return 0; // No adjustment for negative locals
2193 int diff = (callee_locals - callee_parameters) * Interpreter::stackElementWords;
2194 // diff is counted in stack words
2195 return round_to(diff, 2);
2196 }
2197
2198
2199 //------------------------------generate_deopt_blob----------------------------
2200 void SharedRuntime::generate_deopt_blob() {
2201 // Allocate space for the code
2202 ResourceMark rm;
2203 // Setup code generation tools
2204 CodeBuffer buffer("deopt_blob", 2048, 1024);
2205 MacroAssembler* masm = new MacroAssembler(&buffer);
2206 int frame_size_in_words;
2207 OopMap* map = NULL;
2208 OopMapSet *oop_maps = new OopMapSet();
2209
2210 // -------------
2211 // This code enters when returning to a de-optimized nmethod. A return
2212 // address has been pushed on the the stack, and return values are in
2213 // registers.
2214 // If we are doing a normal deopt then we were called from the patched
2215 // nmethod from the point we returned to the nmethod. So the return
2216 // address on the stack is wrong by NativeCall::instruction_size
2217 // We will adjust the value so it looks like we have the original return
2218 // address on the stack (like when we eagerly deoptimized).
2219 // In the case of an exception pending when deoptimizing, we enter
2220 // with a return address on the stack that points after the call we patched
2221 // into the exception handler. We have the following register state from,
2222 // e.g., the forward exception stub (see stubGenerator_x86_64.cpp).
2223 // r0: exception oop
2224 // r19: exception handler
2225 // r3: throwing pc
2226 // So in this case we simply jam r3 into the useless return address and
2227 // the stack looks just like we want.
2228 //
2229 // At this point we need to de-opt. We save the argument return
2230 // registers. We call the first C routine, fetch_unroll_info(). This
2231 // routine captures the return values and returns a structure which
2232 // describes the current frame size and the sizes of all replacement frames.
2233 // The current frame is compiled code and may contain many inlined
2234 // functions, each with their own JVM state. We pop the current frame, then
2235 // push all the new frames. Then we call the C routine unpack_frames() to
2236 // populate these frames. Finally unpack_frames() returns us the new target
2237 // address. Notice that callee-save registers are BLOWN here; they have
2238 // already been captured in the vframeArray at the time the return PC was
2239 // patched.
2240 address start = __ pc();
2241 Label cont;
2242
2243 // Prolog for non exception case!
2244
2245 // Save everything in sight.
2246 map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2247
2248 // Normal deoptimization. Save exec mode for unpack_frames.
2249 __ movw(rcpool, Deoptimization::Unpack_deopt); // callee-saved
2250 __ b(cont);
2251
2252 int reexecute_offset = __ pc() - start;
2253
2254 // Reexecute case
2255 // return address is the pc describes what bci to do re-execute at
2256
2257 // No need to update map as each call to save_live_registers will produce identical oopmap
2258 (void) RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2259
2260 __ movw(rcpool, Deoptimization::Unpack_reexecute); // callee-saved
2261 __ b(cont);
2262
2263 int exception_offset = __ pc() - start;
2264
2265 // Prolog for exception case
2266
2267 // all registers are dead at this entry point, except for r0, and
2268 // r3 which contain the exception oop and exception pc
2269 // respectively. Set them in TLS and fall thru to the
2270 // unpack_with_exception_in_tls entry point.
2271
2272 __ str(r3, Address(rthread, JavaThread::exception_pc_offset()));
2273 __ str(r0, Address(rthread, JavaThread::exception_oop_offset()));
2274
2275 int exception_in_tls_offset = __ pc() - start;
2276
2277 // new implementation because exception oop is now passed in JavaThread
2278
2279 // Prolog for exception case
2280 // All registers must be preserved because they might be used by LinearScan
2281 // Exceptiop oop and throwing PC are passed in JavaThread
2282 // tos: stack at point of call to method that threw the exception (i.e. only
2283 // args are on the stack, no return address)
2284
2285 // The return address pushed by save_live_registers will be patched
2286 // later with the throwing pc. The correct value is not available
2287 // now because loading it from memory would destroy registers.
2288
2289 // NB: The SP at this point must be the SP of the method that is
2290 // being deoptimized. Deoptimization assumes that the frame created
2291 // here by save_live_registers is immediately below the method's SP.
2292 // This is a somewhat fragile mechanism.
2293
2294 // Save everything in sight.
2295 map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2296
2297 // Now it is safe to overwrite any register
2298
2299 // Deopt during an exception. Save exec mode for unpack_frames.
2300 __ mov(rcpool, Deoptimization::Unpack_exception); // callee-saved
2301
2302 // load throwing pc from JavaThread and patch it as the return address
2303 // of the current frame. Then clear the field in JavaThread
2304
2305 __ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
2306 __ str(r3, Address(rfp, wordSize));
2307 __ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
2308
2309 #ifdef ASSERT
2310 // verify that there is really an exception oop in JavaThread
2311 __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2312 __ verify_oop(r0);
2313
2314 // verify that there is no pending exception
2315 Label no_pending_exception;
2316 __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2317 __ cbz(rscratch1, no_pending_exception);
2318 __ stop("must not have pending exception here");
2319 __ bind(no_pending_exception);
2320 #endif
2321
2322 __ bind(cont);
2323
2324 // Call C code. Need thread and this frame, but NOT official VM entry
2325 // crud. We cannot block on this call, no GC can happen.
2326 //
2327 // UnrollBlock* fetch_unroll_info(JavaThread* thread)
2328
2329 // fetch_unroll_info needs to call last_java_frame().
2330
2331 Label retaddr;
2332 __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2333 #ifdef ASSERT0
2334 { Label L;
2335 __ ldr(rscratch1, Address(rthread,
2336 JavaThread::last_Java_fp_offset()));
2337 __ cbz(rscratch1, L);
2338 __ stop("SharedRuntime::generate_deopt_blob: last_Java_fp not cleared");
2339 __ bind(L);
2340 }
2341 #endif // ASSERT
2342 __ mov(c_rarg0, rthread);
2343 __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::fetch_unroll_info)));
2344 __ blr(rscratch1);
2345 __ bind(retaddr);
2346
2347 // Need to have an oopmap that tells fetch_unroll_info where to
2348 // find any register it might need.
2349 oop_maps->add_gc_map(__ pc() - start, map);
2350
2351 __ reset_last_Java_frame(false);
2352
2353 // Load UnrollBlock* into rdi
2354 __ mov(r5, r0);
2355
2356 Label noException;
2357 __ cmpw(rcpool, Deoptimization::Unpack_exception); // Was exception pending?
2358 __ br(Assembler::NE, noException);
2359 __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2360 // QQQ this is useless it was NULL above
2361 __ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
2362 __ str(zr, Address(rthread, JavaThread::exception_oop_offset()));
2363 __ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
2364
2365 __ verify_oop(r0);
2366
2367 // Overwrite the result registers with the exception results.
2368 __ str(r0, Address(sp, RegisterSaver::r0_offset_in_bytes()));
2369 // I think this is useless
2370 // __ str(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
2371
2372 __ bind(noException);
2373
2374 // Only register save data is on the stack.
2375 // Now restore the result registers. Everything else is either dead
2376 // or captured in the vframeArray.
2377 RegisterSaver::restore_result_registers(masm);
2378
2379 // All of the register save area has been popped of the stack. Only the
2380 // return address remains.
2381
2382 // Pop all the frames we must move/replace.
2383 //
2384 // Frame picture (youngest to oldest)
2385 // 1: self-frame (no frame link)
2386 // 2: deopting frame (no frame link)
2387 // 3: caller of deopting frame (could be compiled/interpreted).
2388 //
2389 // Note: by leaving the return address of self-frame on the stack
2390 // and using the size of frame 2 to adjust the stack
2391 // when we are done the return to frame 3 will still be on the stack.
2392
2393 // Pop deoptimized frame
2394 __ ldrw(r2, Address(r5, Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset_in_bytes()));
2395 __ sub(r2, r2, 2 * wordSize);
2396 __ add(sp, sp, r2);
2397 __ ldp(rfp, lr, __ post(sp, 2 * wordSize));
2398 // LR should now be the return address to the caller (3)
2399
2400 // Stack bang to make sure there's enough room for these interpreter frames.
2401 if (UseStackBanging) {
2402 __ ldrw(r19, Address(r5, Deoptimization::UnrollBlock::total_frame_sizes_offset_in_bytes()));
2403 __ bang_stack_size(r19, r2);
2404 }
2405
2406 // Load address of array of frame pcs into r2
2407 __ ldr(r2, Address(r5, Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
2408
2409 // Trash the old pc
2410 // __ addptr(sp, wordSize); FIXME ????
2411
2412 // Load address of array of frame sizes into r4
2413 __ ldr(r4, Address(r5, Deoptimization::UnrollBlock::frame_sizes_offset_in_bytes()));
2414
2415 // Load counter into r3
2416 __ ldrw(r3, Address(r5, Deoptimization::UnrollBlock::number_of_frames_offset_in_bytes()));
2417
2418 // Now adjust the caller's stack to make up for the extra locals
2419 // but record the original sp so that we can save it in the skeletal interpreter
2420 // frame and the stack walking of interpreter_sender will get the unextended sp
2421 // value and not the "real" sp value.
2422
2423 const Register sender_sp = r6;
2424
2425 __ mov(sender_sp, sp);
2426 __ ldrw(r19, Address(r5,
2427 Deoptimization::UnrollBlock::
2428 caller_adjustment_offset_in_bytes()));
2429 __ sub(sp, sp, r19);
2430
2431 // Push interpreter frames in a loop
2432 __ mov(rscratch1, (address)badHeapOopVal); // Make a recognizable pattern
2433 __ mov(rscratch2, rscratch1);
2434 Label loop;
2435 __ bind(loop);
2436 __ ldr(r19, Address(__ post(r4, wordSize))); // Load frame size
2437 __ sub(r19, r19, 2*wordSize); // We'll push pc and fp by hand
2438 __ ldr(lr, Address(__ post(r2, wordSize))); // Load pc
2439 __ enter(); // Save old & set new fp
2440 __ sub(sp, sp, r19); // Prolog
2441 // This value is corrected by layout_activation_impl
2442 __ str(zr, Address(rfp, frame::interpreter_frame_last_sp_offset * wordSize));
2443 __ str(sender_sp, Address(rfp, frame::interpreter_frame_sender_sp_offset * wordSize)); // Make it walkable
2444 __ mov(sender_sp, sp); // Pass sender_sp to next frame
2445 __ sub(r3, r3, 1); // Decrement counter
2446 __ cbnz(r3, loop);
2447
2448 // Re-push self-frame
2449 __ ldr(lr, Address(r2));
2450 __ enter();
2451
2452 // Allocate a full sized register save area. We subtract 2 because
2453 // enter() just pushed 2 words
2454 __ sub(sp, sp, (frame_size_in_words - 2) * wordSize);
2455
2456 // Restore frame locals after moving the frame
2457 __ strd(v0, Address(sp, RegisterSaver::v0_offset_in_bytes()));
2458 __ str(r0, Address(sp, RegisterSaver::r0_offset_in_bytes()));
2459
2460 // Call C code. Need thread but NOT official VM entry
2461 // crud. We cannot block on this call, no GC can happen. Call should
2462 // restore return values to their stack-slots with the new SP.
2463 //
2464 // void Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)
2465
2466 // Use rfp because the frames look interpreted now
2467 // Don't need the precise return PC here, just precise enough to point into this code blob.
2468 address the_pc = __ pc();
2469 __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
2470
2471 __ mov(c_rarg0, rthread);
2472 __ movw(c_rarg1, rcpool); // second arg: exec_mode
2473 __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
2474 __ blr(rscratch1);
2475
2476 // Set an oopmap for the call site
2477 // Use the same PC we used for the last java frame
2478 oop_maps->add_gc_map(the_pc - start,
2479 new OopMap( frame_size_in_words, 0 ));
2480
2481 // Clear fp AND pc
2482 __ reset_last_Java_frame(true);
2483
2484 // Collect return values
2485 __ ldrd(v0, Address(sp, RegisterSaver::v0_offset_in_bytes()));
2486 __ ldr(r0, Address(sp, RegisterSaver::r0_offset_in_bytes()));
2487 // I think this is useless (throwing pc?)
2488 // __ ldr(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
2489
2490 // Pop self-frame.
2491 __ leave(); // Epilog
2492
2493 // Jump to interpreter
2494 __ ret(lr);
2495
2496 // Make sure all code is generated
2497 masm->flush();
2498
2499 _deopt_blob = DeoptimizationBlob::create(&buffer, oop_maps, 0, exception_offset, reexecute_offset, frame_size_in_words);
2500 _deopt_blob->set_unpack_with_exception_in_tls_offset(exception_in_tls_offset);
2501 }
2502
2503 uint SharedRuntime::out_preserve_stack_slots() {
2504 return 0;
2505 }
2506
2507 #ifdef COMPILER2
2508 //------------------------------generate_uncommon_trap_blob--------------------
2509 void SharedRuntime::generate_uncommon_trap_blob() {
2510 // Allocate space for the code
2511 ResourceMark rm;
2512 // Setup code generation tools
2513 CodeBuffer buffer("uncommon_trap_blob", 2048, 1024);
2514 MacroAssembler* masm = new MacroAssembler(&buffer);
2515
2516 assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
2517
2518 address start = __ pc();
2519
2520 // Push self-frame. We get here with a return address in LR
2521 // and sp should be 16 byte aligned
2522 // push rfp and retaddr by hand
2523 __ stp(rfp, lr, Address(__ pre(sp, -2 * wordSize)));
2524 // we don't expect an arg reg save area
2525 #ifndef PRODUCT
2526 assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
2527 #endif
2528 // compiler left unloaded_class_index in j_rarg0 move to where the
2529 // runtime expects it.
2530 if (c_rarg1 != j_rarg0) {
2531 __ movw(c_rarg1, j_rarg0);
2532 }
2533
2534 // we need to set the past SP to the stack pointer of the stub frame
2535 // and the pc to the address where this runtime call will return
2536 // although actually any pc in this code blob will do).
2537 Label retaddr;
2538 __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2539
2540 // Call C code. Need thread but NOT official VM entry
2541 // crud. We cannot block on this call, no GC can happen. Call should
2542 // capture callee-saved registers as well as return values.
2543 // Thread is in rdi already.
2544 //
2545 // UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
2546 //
2547 // n.b. 2 gp args, 0 fp args, integral return type
2548
2549 __ mov(c_rarg0, rthread);
2550 __ lea(rscratch1,
2551 RuntimeAddress(CAST_FROM_FN_PTR(address,
2552 Deoptimization::uncommon_trap)));
2553 __ blr(rscratch1);
2554 __ bind(retaddr);
2555
2556 // Set an oopmap for the call site
2557 OopMapSet* oop_maps = new OopMapSet();
2558 OopMap* map = new OopMap(SimpleRuntimeFrame::framesize, 0);
2559
2560 // location of rfp is known implicitly by the frame sender code
2561
2562 oop_maps->add_gc_map(__ pc() - start, map);
2563
2564 __ reset_last_Java_frame(false);
2565
2566 // move UnrollBlock* into r4
2567 __ mov(r4, r0);
2568
2569 // Pop all the frames we must move/replace.
2570 //
2571 // Frame picture (youngest to oldest)
2572 // 1: self-frame (no frame link)
2573 // 2: deopting frame (no frame link)
2574 // 3: caller of deopting frame (could be compiled/interpreted).
2575
2576 // Pop self-frame. We have no frame, and must rely only on r0 and sp.
2577 __ add(sp, sp, (SimpleRuntimeFrame::framesize) << LogBytesPerInt); // Epilog!
2578
2579 // Pop deoptimized frame (int)
2580 __ ldrw(r2, Address(r4,
2581 Deoptimization::UnrollBlock::
2582 size_of_deoptimized_frame_offset_in_bytes()));
2583 __ sub(r2, r2, 2 * wordSize);
2584 __ add(sp, sp, r2);
2585 __ ldp(rfp, lr, __ post(sp, 2 * wordSize));
2586 // LR should now be the return address to the caller (3) frame
2587
2588 // Stack bang to make sure there's enough room for these interpreter frames.
2589 if (UseStackBanging) {
2590 __ ldrw(r1, Address(r4,
2591 Deoptimization::UnrollBlock::
2592 total_frame_sizes_offset_in_bytes()));
2593 __ bang_stack_size(r1, r2);
2594 }
2595
2596 // Load address of array of frame pcs into r2 (address*)
2597 __ ldr(r2, Address(r4,
2598 Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
2599
2600 // Load address of array of frame sizes into r5 (intptr_t*)
2601 __ ldr(r5, Address(r4,
2602 Deoptimization::UnrollBlock::
2603 frame_sizes_offset_in_bytes()));
2604
2605 // Counter
2606 __ ldrw(r3, Address(r4,
2607 Deoptimization::UnrollBlock::
2608 number_of_frames_offset_in_bytes())); // (int)
2609
2610 // Now adjust the caller's stack to make up for the extra locals but
2611 // record the original sp so that we can save it in the skeletal
2612 // interpreter frame and the stack walking of interpreter_sender
2613 // will get the unextended sp value and not the "real" sp value.
2614
2615 const Register sender_sp = r8;
2616
2617 __ mov(sender_sp, sp);
2618 __ ldrw(r1, Address(r4,
2619 Deoptimization::UnrollBlock::
2620 caller_adjustment_offset_in_bytes())); // (int)
2621 __ sub(sp, sp, r1);
2622
2623 // Push interpreter frames in a loop
2624 Label loop;
2625 __ bind(loop);
2626 __ ldr(r1, Address(r5, 0)); // Load frame size
2627 __ sub(r1, r1, 2 * wordSize); // We'll push pc and rfp by hand
2628 __ ldr(lr, Address(r2, 0)); // Save return address
2629 __ enter(); // and old rfp & set new rfp
2630 __ sub(sp, sp, r1); // Prolog
2631 __ str(sender_sp, Address(rfp, frame::interpreter_frame_sender_sp_offset * wordSize)); // Make it walkable
2632 // This value is corrected by layout_activation_impl
2633 __ str(zr, Address(rfp, frame::interpreter_frame_last_sp_offset * wordSize));
2634 __ mov(sender_sp, sp); // Pass sender_sp to next frame
2635 __ add(r5, r5, wordSize); // Bump array pointer (sizes)
2636 __ add(r2, r2, wordSize); // Bump array pointer (pcs)
2637 __ subsw(r3, r3, 1); // Decrement counter
2638 __ br(Assembler::GT, loop);
2639 __ ldr(lr, Address(r2, 0)); // save final return address
2640 // Re-push self-frame
2641 __ enter(); // & old rfp & set new rfp
2642
2643 // Use rfp because the frames look interpreted now
2644 // Save "the_pc" since it cannot easily be retrieved using the last_java_SP after we aligned SP.
2645 // Don't need the precise return PC here, just precise enough to point into this code blob.
2646 address the_pc = __ pc();
2647 __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
2648
2649 // Call C code. Need thread but NOT official VM entry
2650 // crud. We cannot block on this call, no GC can happen. Call should
2651 // restore return values to their stack-slots with the new SP.
2652 // Thread is in rdi already.
2653 //
2654 // BasicType unpack_frames(JavaThread* thread, int exec_mode);
2655 //
2656 // n.b. 2 gp args, 0 fp args, integral return type
2657
2658 // sp should already be aligned
2659 __ mov(c_rarg0, rthread);
2660 __ movw(c_rarg1, (unsigned)Deoptimization::Unpack_uncommon_trap);
2661 __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
2662 __ blr(rscratch1);
2663
2664 // Set an oopmap for the call site
2665 // Use the same PC we used for the last java frame
2666 oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
2667
2668 // Clear fp AND pc
2669 __ reset_last_Java_frame(true);
2670
2671 // Pop self-frame.
2672 __ leave(); // Epilog
2673
2674 // Jump to interpreter
2675 __ ret(lr);
2676
2677 // Make sure all code is generated
2678 masm->flush();
2679
2680 _uncommon_trap_blob = UncommonTrapBlob::create(&buffer, oop_maps,
2681 SimpleRuntimeFrame::framesize >> 1);
2682 }
2683 #endif // COMPILER2
2684
2685
2686 //------------------------------generate_handler_blob------
2687 //
2688 // Generate a special Compile2Runtime blob that saves all registers,
2689 // and setup oopmap.
2690 //
2691 SafepointBlob* SharedRuntime::generate_handler_blob(address call_ptr, int poll_type) {
2692 ResourceMark rm;
2693 OopMapSet *oop_maps = new OopMapSet();
2694 OopMap* map;
2695
2696 // Allocate space for the code. Setup code generation tools.
2697 CodeBuffer buffer("handler_blob", 2048, 1024);
2698 MacroAssembler* masm = new MacroAssembler(&buffer);
2699
2700 address start = __ pc();
2701 address call_pc = NULL;
2702 int frame_size_in_words;
2703 bool cause_return = (poll_type == POLL_AT_RETURN);
2704 bool save_vectors = (poll_type == POLL_AT_VECTOR_LOOP);
2705
2706 // Save Integer and Float registers.
2707 map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words, save_vectors);
2708
2709 // The following is basically a call_VM. However, we need the precise
2710 // address of the call in order to generate an oopmap. Hence, we do all the
2711 // work outselves.
2712
2713 Label retaddr;
2714 __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2715
2716 // The return address must always be correct so that frame constructor never
2717 // sees an invalid pc.
2718
2719 if (!cause_return) {
2720 // overwrite the return address pushed by save_live_registers
2721 __ ldr(c_rarg0, Address(rthread, JavaThread::saved_exception_pc_offset()));
2722 __ str(c_rarg0, Address(rfp, wordSize));
2723 }
2724
2725 // Do the call
2726 __ mov(c_rarg0, rthread);
2727 __ lea(rscratch1, RuntimeAddress(call_ptr));
2728 __ blr(rscratch1);
2729 __ bind(retaddr);
2730
2731 // Set an oopmap for the call site. This oopmap will map all
2732 // oop-registers and debug-info registers as callee-saved. This
2733 // will allow deoptimization at this safepoint to find all possible
2734 // debug-info recordings, as well as let GC find all oops.
2735
2736 oop_maps->add_gc_map( __ pc() - start, map);
2737
2738 Label noException;
2739
2740 __ reset_last_Java_frame(false);
2741
2742 __ maybe_isb();
2743 __ membar(Assembler::LoadLoad | Assembler::LoadStore);
2744
2745 __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2746 __ cbz(rscratch1, noException);
2747
2748 // Exception pending
2749
2750 RegisterSaver::restore_live_registers(masm);
2751
2752 __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2753
2754 // No exception case
2755 __ bind(noException);
2756
2757 // Normal exit, restore registers and exit.
2758 RegisterSaver::restore_live_registers(masm, save_vectors);
2759
2760 __ ret(lr);
2761
2762 // Make sure all code is generated
2763 masm->flush();
2764
2765 // Fill-out other meta info
2766 return SafepointBlob::create(&buffer, oop_maps, frame_size_in_words);
2767 }
2768
2769 //
2770 // generate_resolve_blob - call resolution (static/virtual/opt-virtual/ic-miss
2771 //
2772 // Generate a stub that calls into vm to find out the proper destination
2773 // of a java call. All the argument registers are live at this point
2774 // but since this is generic code we don't know what they are and the caller
2775 // must do any gc of the args.
2776 //
2777 RuntimeStub* SharedRuntime::generate_resolve_blob(address destination, const char* name) {
2778 assert (StubRoutines::forward_exception_entry() != NULL, "must be generated before");
2779
2780 // allocate space for the code
2781 ResourceMark rm;
2782
2783 CodeBuffer buffer(name, 1000, 512);
2784 MacroAssembler* masm = new MacroAssembler(&buffer);
2785
2786 int frame_size_in_words;
2787
2788 OopMapSet *oop_maps = new OopMapSet();
2789 OopMap* map = NULL;
2790
2791 int start = __ offset();
2792
2793 map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2794
2795 int frame_complete = __ offset();
2796
2797 {
2798 Label retaddr;
2799 __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2800
2801 __ mov(c_rarg0, rthread);
2802 __ lea(rscratch1, RuntimeAddress(destination));
2803
2804 __ blr(rscratch1);
2805 __ bind(retaddr);
2806 }
2807
2808 // Set an oopmap for the call site.
2809 // We need this not only for callee-saved registers, but also for volatile
2810 // registers that the compiler might be keeping live across a safepoint.
2811
2812 oop_maps->add_gc_map( __ offset() - start, map);
2813
2814 __ maybe_isb();
2815
2816 // r0 contains the address we are going to jump to assuming no exception got installed
2817
2818 // clear last_Java_sp
2819 __ reset_last_Java_frame(false);
2820 // check for pending exceptions
2821 Label pending;
2822 __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2823 __ cbnz(rscratch1, pending);
2824
2825 // get the returned Method*
2826 __ get_vm_result_2(rmethod, rthread);
2827 __ str(rmethod, Address(sp, RegisterSaver::reg_offset_in_bytes(rmethod)));
2828
2829 // r0 is where we want to jump, overwrite rscratch1 which is saved and scratch
2830 __ str(r0, Address(sp, RegisterSaver::rscratch1_offset_in_bytes()));
2831 RegisterSaver::restore_live_registers(masm);
2832
2833 // We are back the the original state on entry and ready to go.
2834
2835 __ br(rscratch1);
2836
2837 // Pending exception after the safepoint
2838
2839 __ bind(pending);
2840
2841 RegisterSaver::restore_live_registers(masm);
2842
2843 // exception pending => remove activation and forward to exception handler
2844
2845 __ str(zr, Address(rthread, JavaThread::vm_result_offset()));
2846
2847 __ ldr(r0, Address(rthread, Thread::pending_exception_offset()));
2848 __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2849
2850 // -------------
2851 // make sure all code is generated
2852 masm->flush();
2853
2854 // return the blob
2855 // frame_size_words or bytes??
2856 return RuntimeStub::new_runtime_stub(name, &buffer, frame_complete, frame_size_in_words, oop_maps, true);
2857 }
2858
2859
2860 #ifdef COMPILER2
2861 // This is here instead of runtime_x86_64.cpp because it uses SimpleRuntimeFrame
2862 //
2863 //------------------------------generate_exception_blob---------------------------
2864 // creates exception blob at the end
2865 // Using exception blob, this code is jumped from a compiled method.
2866 // (see emit_exception_handler in x86_64.ad file)
2867 //
2868 // Given an exception pc at a call we call into the runtime for the
2869 // handler in this method. This handler might merely restore state
2870 // (i.e. callee save registers) unwind the frame and jump to the
2871 // exception handler for the nmethod if there is no Java level handler
2872 // for the nmethod.
2873 //
2874 // This code is entered with a jmp.
2875 //
2876 // Arguments:
2877 // r0: exception oop
2878 // r3: exception pc
2879 //
2880 // Results:
2881 // r0: exception oop
2882 // r3: exception pc in caller or ???
2883 // destination: exception handler of caller
2884 //
2885 // Note: the exception pc MUST be at a call (precise debug information)
2886 // Registers r0, r3, r2, r4, r5, r8-r11 are not callee saved.
2887 //
2888
2889 void OptoRuntime::generate_exception_blob() {
2890 assert(!OptoRuntime::is_callee_saved_register(R3_num), "");
2891 assert(!OptoRuntime::is_callee_saved_register(R0_num), "");
2892 assert(!OptoRuntime::is_callee_saved_register(R2_num), "");
2893
2894 assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
2895
2896 // Allocate space for the code
2897 ResourceMark rm;
2898 // Setup code generation tools
2899 CodeBuffer buffer("exception_blob", 2048, 1024);
2900 MacroAssembler* masm = new MacroAssembler(&buffer);
2901
2902 // TODO check various assumptions made here
2903 //
2904 // make sure we do so before running this
2905
2906 address start = __ pc();
2907
2908 // push rfp and retaddr by hand
2909 // Exception pc is 'return address' for stack walker
2910 __ stp(rfp, lr, Address(__ pre(sp, -2 * wordSize)));
2911 // there are no callee save registers and we don't expect an
2912 // arg reg save area
2913 #ifndef PRODUCT
2914 assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
2915 #endif
2916 // Store exception in Thread object. We cannot pass any arguments to the
2917 // handle_exception call, since we do not want to make any assumption
2918 // about the size of the frame where the exception happened in.
2919 __ str(r0, Address(rthread, JavaThread::exception_oop_offset()));
2920 __ str(r3, Address(rthread, JavaThread::exception_pc_offset()));
2921
2922 // This call does all the hard work. It checks if an exception handler
2923 // exists in the method.
2924 // If so, it returns the handler address.
2925 // If not, it prepares for stack-unwinding, restoring the callee-save
2926 // registers of the frame being removed.
2927 //
2928 // address OptoRuntime::handle_exception_C(JavaThread* thread)
2929 //
2930 // n.b. 1 gp arg, 0 fp args, integral return type
2931
2932 // the stack should always be aligned
2933 address the_pc = __ pc();
2934 __ set_last_Java_frame(sp, noreg, the_pc, rscratch1);
2935 __ mov(c_rarg0, rthread);
2936 __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
2937 __ blr(rscratch1);
2938 __ maybe_isb();
2939
2940 // Set an oopmap for the call site. This oopmap will only be used if we
2941 // are unwinding the stack. Hence, all locations will be dead.
2942 // Callee-saved registers will be the same as the frame above (i.e.,
2943 // handle_exception_stub), since they were restored when we got the
2944 // exception.
2945
2946 OopMapSet* oop_maps = new OopMapSet();
2947
2948 oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
2949
2950 __ reset_last_Java_frame(false);
2951
2952 // Restore callee-saved registers
2953
2954 // rfp is an implicitly saved callee saved register (i.e. the calling
2955 // convention will save restore it in prolog/epilog) Other than that
2956 // there are no callee save registers now that adapter frames are gone.
2957 // and we dont' expect an arg reg save area
2958 __ ldp(rfp, r3, Address(__ post(sp, 2 * wordSize)));
2959
2960 // r0: exception handler
2961
2962 // Restore SP from BP if the exception PC is a MethodHandle call site.
2963 __ ldrw(rscratch1, Address(rthread, JavaThread::is_method_handle_return_offset()));
2964 // n.b. Intel uses special register rbp_mh_SP_save here but we will
2965 // just hard wire rfp
2966 __ cmpw(rscratch1, zr);
2967 // the obvious way to conditionally copy rfp to sp if NE
2968 // Label skip;
2969 // __ br(Assembler::EQ, skip);
2970 // __ mov(sp, rfp);
2971 // __ bind(skip);
2972 // same but branchless
2973 __ mov(rscratch1, sp);
2974 __ csel(rscratch1, rfp, rscratch1, Assembler::NE);
2975 __ mov(sp, rscratch1);
2976
2977 // We have a handler in r0 (could be deopt blob).
2978 __ mov(r8, r0);
2979
2980 // Get the exception oop
2981 __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2982 // Get the exception pc in case we are deoptimized
2983 __ ldr(r4, Address(rthread, JavaThread::exception_pc_offset()));
2984 #ifdef ASSERT
2985 __ str(zr, Address(rthread, JavaThread::exception_handler_pc_offset()));
2986 __ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
2987 #endif
2988 // Clear the exception oop so GC no longer processes it as a root.
2989 __ str(zr, Address(rthread, JavaThread::exception_oop_offset()));
2990
2991 // r0: exception oop
2992 // r8: exception handler
2993 // r4: exception pc
2994 // Jump to handler
2995
2996 __ br(r8);
2997
2998 // Make sure all code is generated
2999 masm->flush();
3000
3001 // Set exception blob
3002 _exception_blob = ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
3003 }
3004 #endif // COMPILER2