1/*
2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2012, 2015 SAP SE. 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 "c1/c1_MacroAssembler.hpp"
28#include "c1/c1_Runtime1.hpp"
29#include "classfile/systemDictionary.hpp"
30#include "gc/shared/collectedHeap.hpp"
31#include "interpreter/interpreter.hpp"
32#include "oops/arrayOop.hpp"
33#include "oops/markOop.hpp"
34#include "runtime/basicLock.hpp"
35#include "runtime/biasedLocking.hpp"
36#include "runtime/os.hpp"
37#include "runtime/stubRoutines.hpp"
38#include "runtime/sharedRuntime.hpp"
39
40
41void C1_MacroAssembler::inline_cache_check(Register receiver, Register iCache) {
42  const Register temp_reg = R12_scratch2;
43  verify_oop(receiver);
44  load_klass(temp_reg, receiver);
45  if (TrapBasedICMissChecks) {
46    trap_ic_miss_check(temp_reg, iCache);
47  } else {
48    Label L;
49    cmpd(CCR0, temp_reg, iCache);
50    beq(CCR0, L);
51    //load_const_optimized(temp_reg, SharedRuntime::get_ic_miss_stub(), R0);
52    calculate_address_from_global_toc(temp_reg, SharedRuntime::get_ic_miss_stub(), true, true, false);
53    mtctr(temp_reg);
54    bctr();
55    align(32, 12);
56    bind(L);
57  }
58}
59
60
61void C1_MacroAssembler::explicit_null_check(Register base) {
62  Unimplemented();
63}
64
65
66void C1_MacroAssembler::build_frame(int frame_size_in_bytes, int bang_size_in_bytes) {
67  // Avoid stack bang as first instruction. It may get overwritten by patch_verified_entry.
68  const Register return_pc = R20;
69  mflr(return_pc);
70
71  // Make sure there is enough stack space for this method's activation.
72  assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
73  generate_stack_overflow_check(bang_size_in_bytes);
74
75  std(return_pc, _abi(lr), R1_SP);     // SP->lr = return_pc
76  push_frame(frame_size_in_bytes, R0); // SP -= frame_size_in_bytes
77}
78
79
80void C1_MacroAssembler::unverified_entry(Register receiver, Register ic_klass) {
81  Unimplemented(); // Currently unused.
82  //if (C1Breakpoint) illtrap();
83  //inline_cache_check(receiver, ic_klass);
84}
85
86
87void C1_MacroAssembler::verified_entry() {
88  if (C1Breakpoint) illtrap();
89  // build frame
90}
91
92
93void C1_MacroAssembler::lock_object(Register Rmark, Register Roop, Register Rbox, Register Rscratch, Label& slow_case) {
94  assert_different_registers(Rmark, Roop, Rbox, Rscratch);
95
96  Label done, cas_failed, slow_int;
97
98  // The following move must be the first instruction of emitted since debug
99  // information may be generated for it.
100  // Load object header.
101  ld(Rmark, oopDesc::mark_offset_in_bytes(), Roop);
102
103  verify_oop(Roop);
104
105  // Save object being locked into the BasicObjectLock...
106  std(Roop, BasicObjectLock::obj_offset_in_bytes(), Rbox);
107
108  if (UseBiasedLocking) {
109    biased_locking_enter(CCR0, Roop, Rmark, Rscratch, R0, done, &slow_int);
110  }
111
112  // ... and mark it unlocked.
113  ori(Rmark, Rmark, markOopDesc::unlocked_value);
114
115  // Save unlocked object header into the displaced header location on the stack.
116  std(Rmark, BasicLock::displaced_header_offset_in_bytes(), Rbox);
117
118  // Compare object markOop with Rmark and if equal exchange Rscratch with object markOop.
119  assert(oopDesc::mark_offset_in_bytes() == 0, "cas must take a zero displacement");
120  cmpxchgd(/*flag=*/CCR0,
121           /*current_value=*/Rscratch,
122           /*compare_value=*/Rmark,
123           /*exchange_value=*/Rbox,
124           /*where=*/Roop/*+0==mark_offset_in_bytes*/,
125           MacroAssembler::MemBarRel | MacroAssembler::MemBarAcq,
126           MacroAssembler::cmpxchgx_hint_acquire_lock(),
127           noreg,
128           &cas_failed,
129           /*check without membar and ldarx first*/true);
130  // If compare/exchange succeeded we found an unlocked object and we now have locked it
131  // hence we are done.
132  b(done);
133
134  bind(slow_int);
135  b(slow_case); // far
136
137  bind(cas_failed);
138  // We did not find an unlocked object so see if this is a recursive case.
139  sub(Rscratch, Rscratch, R1_SP);
140  load_const_optimized(R0, (~(os::vm_page_size()-1) | markOopDesc::lock_mask_in_place));
141  and_(R0/*==0?*/, Rscratch, R0);
142  std(R0/*==0, perhaps*/, BasicLock::displaced_header_offset_in_bytes(), Rbox);
143  bne(CCR0, slow_int);
144
145  bind(done);
146}
147
148
149void C1_MacroAssembler::unlock_object(Register Rmark, Register Roop, Register Rbox, Label& slow_case) {
150  assert_different_registers(Rmark, Roop, Rbox);
151
152  Label slow_int, done;
153
154  Address mark_addr(Roop, oopDesc::mark_offset_in_bytes());
155  assert(mark_addr.disp() == 0, "cas must take a zero displacement");
156
157  if (UseBiasedLocking) {
158    // Load the object out of the BasicObjectLock.
159    ld(Roop, BasicObjectLock::obj_offset_in_bytes(), Rbox);
160    verify_oop(Roop);
161    biased_locking_exit(CCR0, Roop, R0, done);
162  }
163  // Test first it it is a fast recursive unlock.
164  ld(Rmark, BasicLock::displaced_header_offset_in_bytes(), Rbox);
165  cmpdi(CCR0, Rmark, 0);
166  beq(CCR0, done);
167  if (!UseBiasedLocking) {
168    // Load object.
169    ld(Roop, BasicObjectLock::obj_offset_in_bytes(), Rbox);
170    verify_oop(Roop);
171  }
172
173  // Check if it is still a light weight lock, this is is true if we see
174  // the stack address of the basicLock in the markOop of the object.
175  cmpxchgd(/*flag=*/CCR0,
176           /*current_value=*/R0,
177           /*compare_value=*/Rbox,
178           /*exchange_value=*/Rmark,
179           /*where=*/Roop,
180           MacroAssembler::MemBarRel,
181           MacroAssembler::cmpxchgx_hint_release_lock(),
182           noreg,
183           &slow_int);
184  b(done);
185  bind(slow_int);
186  b(slow_case); // far
187
188  // Done
189  bind(done);
190}
191
192
193void C1_MacroAssembler::try_allocate(
194  Register obj,                        // result: pointer to object after successful allocation
195  Register var_size_in_bytes,          // object size in bytes if unknown at compile time; invalid otherwise
196  int      con_size_in_bytes,          // object size in bytes if   known at compile time
197  Register t1,                         // temp register, must be global register for incr_allocated_bytes
198  Register t2,                         // temp register
199  Label&   slow_case                   // continuation point if fast allocation fails
200) {
201  if (UseTLAB) {
202    tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, slow_case);
203  } else {
204    eden_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case);
205    RegisterOrConstant size_in_bytes = var_size_in_bytes->is_valid()
206                                       ? RegisterOrConstant(var_size_in_bytes)
207                                       : RegisterOrConstant(con_size_in_bytes);
208    incr_allocated_bytes(size_in_bytes, t1, t2);
209  }
210}
211
212
213void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
214  assert_different_registers(obj, klass, len, t1, t2);
215  if (UseBiasedLocking && !len->is_valid()) {
216    ld(t1, in_bytes(Klass::prototype_header_offset()), klass);
217  } else {
218    load_const_optimized(t1, (intx)markOopDesc::prototype());
219  }
220  std(t1, oopDesc::mark_offset_in_bytes(), obj);
221  store_klass(obj, klass);
222  if (len->is_valid()) {
223    stw(len, arrayOopDesc::length_offset_in_bytes(), obj);
224  } else if (UseCompressedClassPointers) {
225    // Otherwise length is in the class gap.
226    store_klass_gap(obj);
227  }
228}
229
230
231void C1_MacroAssembler::initialize_body(Register base, Register index) {
232  assert_different_registers(base, index);
233  srdi(index, index, LogBytesPerWord);
234  clear_memory_doubleword(base, index);
235}
236
237void C1_MacroAssembler::initialize_body(Register obj, Register tmp1, Register tmp2,
238                                        int obj_size_in_bytes, int hdr_size_in_bytes) {
239  const int index = (obj_size_in_bytes - hdr_size_in_bytes) / HeapWordSize;
240
241  // 2x unrolled loop is shorter with more than 9 HeapWords.
242  if (index <= 9) {
243    clear_memory_unrolled(obj, index, R0, hdr_size_in_bytes);
244  } else {
245    const Register base_ptr = tmp1,
246                   cnt_dwords = tmp2;
247
248    addi(base_ptr, obj, hdr_size_in_bytes); // Compute address of first element.
249    clear_memory_doubleword(base_ptr, cnt_dwords, R0, index);
250  }
251}
252
253void C1_MacroAssembler::allocate_object(
254  Register obj,                        // result: pointer to object after successful allocation
255  Register t1,                         // temp register
256  Register t2,                         // temp register
257  Register t3,                         // temp register
258  int      hdr_size,                   // object header size in words
259  int      obj_size,                   // object size in words
260  Register klass,                      // object klass
261  Label&   slow_case                   // continuation point if fast allocation fails
262) {
263  assert_different_registers(obj, t1, t2, t3, klass);
264
265  // allocate space & initialize header
266  if (!is_simm16(obj_size * wordSize)) {
267    // Would need to use extra register to load
268    // object size => go the slow case for now.
269    b(slow_case);
270    return;
271  }
272  try_allocate(obj, noreg, obj_size * wordSize, t2, t3, slow_case);
273
274  initialize_object(obj, klass, noreg, obj_size * HeapWordSize, t1, t2);
275}
276
277void C1_MacroAssembler::initialize_object(
278  Register obj,                        // result: pointer to object after successful allocation
279  Register klass,                      // object klass
280  Register var_size_in_bytes,          // object size in bytes if unknown at compile time; invalid otherwise
281  int      con_size_in_bytes,          // object size in bytes if   known at compile time
282  Register t1,                         // temp register
283  Register t2                          // temp register
284  ) {
285  const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize;
286
287  initialize_header(obj, klass, noreg, t1, t2);
288
289#ifdef ASSERT
290  {
291    lwz(t1, in_bytes(Klass::layout_helper_offset()), klass);
292    if (var_size_in_bytes != noreg) {
293      cmpw(CCR0, t1, var_size_in_bytes);
294    } else {
295      cmpwi(CCR0, t1, con_size_in_bytes);
296    }
297    asm_assert_eq("bad size in initialize_object", 0x753);
298  }
299#endif
300
301  // Initialize body.
302  if (var_size_in_bytes != noreg) {
303    // Use a loop.
304    addi(t1, obj, hdr_size_in_bytes);                // Compute address of first element.
305    addi(t2, var_size_in_bytes, -hdr_size_in_bytes); // Compute size of body.
306    initialize_body(t1, t2);
307  } else if (con_size_in_bytes > hdr_size_in_bytes) {
308    // Use a loop.
309    initialize_body(obj, t1, t2, con_size_in_bytes, hdr_size_in_bytes);
310  }
311
312  if (CURRENT_ENV->dtrace_alloc_probes()) {
313    Unimplemented();
314//    assert(obj == O0, "must be");
315//    call(CAST_FROM_FN_PTR(address, Runtime1::entry_for(Runtime1::dtrace_object_alloc_id)),
316//         relocInfo::runtime_call_type);
317  }
318
319  verify_oop(obj);
320}
321
322
323void C1_MacroAssembler::allocate_array(
324  Register obj,                        // result: pointer to array after successful allocation
325  Register len,                        // array length
326  Register t1,                         // temp register
327  Register t2,                         // temp register
328  Register t3,                         // temp register
329  int      hdr_size,                   // object header size in words
330  int      elt_size,                   // element size in bytes
331  Register klass,                      // object klass
332  Label&   slow_case                   // continuation point if fast allocation fails
333) {
334  assert_different_registers(obj, len, t1, t2, t3, klass);
335
336  // Determine alignment mask.
337  assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work");
338  int log2_elt_size = exact_log2(elt_size);
339
340  // Check for negative or excessive length.
341  size_t max_length = max_array_allocation_length >> log2_elt_size;
342  if (UseTLAB) {
343    size_t max_tlab = align_size_up(ThreadLocalAllocBuffer::max_size() >> log2_elt_size, 64*K);
344    if (max_tlab < max_length) { max_length = max_tlab; }
345  }
346  load_const_optimized(t1, max_length);
347  cmpld(CCR0, len, t1);
348  bc_far_optimized(Assembler::bcondCRbiIs1, bi0(CCR0, Assembler::greater), slow_case);
349
350  // compute array size
351  // note: If 0 <= len <= max_length, len*elt_size + header + alignment is
352  //       smaller or equal to the largest integer; also, since top is always
353  //       aligned, we can do the alignment here instead of at the end address
354  //       computation.
355  const Register arr_size = t1;
356  Register arr_len_in_bytes = len;
357  if (elt_size != 1) {
358    sldi(t1, len, log2_elt_size);
359    arr_len_in_bytes = t1;
360  }
361  addi(arr_size, arr_len_in_bytes, hdr_size * wordSize + MinObjAlignmentInBytesMask); // Add space for header & alignment.
362  clrrdi(arr_size, arr_size, LogMinObjAlignmentInBytes);                              // Align array size.
363
364  // Allocate space & initialize header.
365  if (UseTLAB) {
366    tlab_allocate(obj, arr_size, 0, t2, slow_case);
367  } else {
368    eden_allocate(obj, arr_size, 0, t2, t3, slow_case);
369  }
370  initialize_header(obj, klass, len, t2, t3);
371
372  // Initialize body.
373  const Register base  = t2;
374  const Register index = t3;
375  addi(base, obj, hdr_size * wordSize);               // compute address of first element
376  addi(index, arr_size, -(hdr_size * wordSize));      // compute index = number of bytes to clear
377  initialize_body(base, index);
378
379  if (CURRENT_ENV->dtrace_alloc_probes()) {
380    Unimplemented();
381    //assert(obj == O0, "must be");
382    //call(CAST_FROM_FN_PTR(address, Runtime1::entry_for(Runtime1::dtrace_object_alloc_id)),
383    //     relocInfo::runtime_call_type);
384  }
385
386  verify_oop(obj);
387}
388
389
390#ifndef PRODUCT
391
392void C1_MacroAssembler::verify_stack_oop(int stack_offset) {
393  verify_oop_addr((RegisterOrConstant)(stack_offset + STACK_BIAS), R1_SP, "broken oop in stack slot");
394}
395
396void C1_MacroAssembler::verify_not_null_oop(Register r) {
397  Label not_null;
398  cmpdi(CCR0, r, 0);
399  bne(CCR0, not_null);
400  stop("non-null oop required");
401  bind(not_null);
402  if (!VerifyOops) return;
403  verify_oop(r);
404}
405
406#endif // PRODUCT
407
408void C1_MacroAssembler::null_check(Register r, Label* Lnull) {
409  if (TrapBasedNullChecks) { // SIGTRAP based
410    trap_null_check(r);
411  } else { // explicit
412    //const address exception_entry = Runtime1::entry_for(Runtime1::throw_null_pointer_exception_id);
413    assert(Lnull != NULL, "must have Label for explicit check");
414    cmpdi(CCR0, r, 0);
415    bc_far_optimized(Assembler::bcondCRbiIs1, bi0(CCR0, Assembler::equal), *Lnull);
416  }
417}
418
419address C1_MacroAssembler::call_c_with_frame_resize(address dest, int frame_resize) {
420  if (frame_resize) { resize_frame(-frame_resize, R0); }
421#if defined(ABI_ELFv2)
422  address return_pc = call_c(dest, relocInfo::runtime_call_type);
423#else
424  address return_pc = call_c(CAST_FROM_FN_PTR(FunctionDescriptor*, dest), relocInfo::runtime_call_type);
425#endif
426  if (frame_resize) { resize_frame(frame_resize, R0); }
427  return return_pc;
428}
429