1 /*
2 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #include "c1/c1_MacroAssembler.hpp"
26 #include "c1/c1_Runtime1.hpp"
27 #include "code/compiledIC.hpp"
28 #include "compiler/compilerDefinitions.inline.hpp"
29 #include "gc/shared/barrierSet.hpp"
30 #include "gc/shared/barrierSetAssembler.hpp"
31 #include "gc/shared/collectedHeap.hpp"
32 #include "gc/shared/tlab_globals.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "oops/arrayOop.hpp"
35 #include "oops/markWord.hpp"
36 #include "runtime/arguments.hpp"
37 #include "runtime/basicLock.hpp"
38 #include "runtime/frame.inline.hpp"
39 #include "runtime/globals.hpp"
40 #include "runtime/os.hpp"
41 #include "runtime/sharedRuntime.hpp"
42 #include "runtime/stubRoutines.hpp"
43 #include "utilities/checkedCast.hpp"
44 #include "utilities/globalDefinitions.hpp"
45
46 int C1_MacroAssembler::lock_object(Register hdr, Register obj, Register basic_lock, Register tmp, Label& slow_case) {
47 assert(hdr == rax, "hdr must be rax, for the cmpxchg instruction");
48 assert_different_registers(hdr, obj, basic_lock, tmp);
49 int null_check_offset = -1;
50
51 verify_oop(obj);
52
53 // save object being locked into the BasicObjectLock
54 movptr(Address(basic_lock, BasicObjectLock::obj_offset()), obj);
55
56 null_check_offset = offset();
57
58 fast_lock(basic_lock, obj, hdr, tmp, slow_case);
59
60 return null_check_offset;
61 }
62
63 void C1_MacroAssembler::unlock_object(Register hdr, Register obj, Register basic_lock, Label& slow_case) {
64 assert(basic_lock == rax, "basic_lock must be rax, for the cmpxchg instruction");
65 assert(hdr != obj && hdr != basic_lock && obj != basic_lock, "registers must be different");
66
67 // load object
68 movptr(obj, Address(basic_lock, BasicObjectLock::obj_offset()));
69 verify_oop(obj);
70
71 fast_unlock(obj, rax, hdr, slow_case);
72 }
73
74
75 // Defines obj, preserves var_size_in_bytes
76 void C1_MacroAssembler::try_allocate(Register obj, Register var_size_in_bytes, int con_size_in_bytes, Register t1, Register t2, Label& slow_case) {
77 if (UseTLAB) {
78 tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case);
79 } else {
80 jmp(slow_case);
81 }
82 }
83
84
85 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
86 assert_different_registers(obj, klass, len, t1, t2);
87 if (UseCompactObjectHeaders || Arguments::is_valhalla_enabled()) {
88 // COH: Markword contains class pointer which is only known at runtime.
89 // Valhalla: Could have value class which has a different prototype header to a normal object.
90 // In both cases, we need to fetch dynamically.
91 movptr(t1, Address(klass, Klass::prototype_header_offset()));
92 movptr(Address(obj, oopDesc::mark_offset_in_bytes()), t1);
93 } else {
94 // Otherwise: Can use the statically computed prototype header which is the same for every object.
95 movptr(Address(obj, oopDesc::mark_offset_in_bytes()), checked_cast<int32_t>(markWord::prototype().value()));
96 }
97 if (!UseCompactObjectHeaders) {
98 // COH: Markword already contains class pointer. Nothing else to do.
99 // Otherwise: Fetch klass pointer following the markword
100 if (UseCompressedClassPointers) { // Take care not to kill klass
101 movptr(t1, klass);
102 encode_klass_not_null(t1, rscratch1);
103 movl(Address(obj, oopDesc::klass_offset_in_bytes()), t1);
104 } else {
105 movptr(Address(obj, oopDesc::klass_offset_in_bytes()), klass);
106 }
107 }
108
109 if (len->is_valid()) {
110 movl(Address(obj, arrayOopDesc::length_offset_in_bytes()), len);
111 int base_offset = arrayOopDesc::length_offset_in_bytes() + BytesPerInt;
112 if (!is_aligned(base_offset, BytesPerWord)) {
113 assert(is_aligned(base_offset, BytesPerInt), "must be 4-byte aligned");
114 // Clear gap/first 4 bytes following the length field.
115 xorl(t1, t1);
116 movl(Address(obj, base_offset), t1);
117 }
118 } else if (UseCompressedClassPointers && !UseCompactObjectHeaders) {
119 xorptr(t1, t1);
120 store_klass_gap(obj, t1);
121 }
122 }
123
124
125 // preserves obj, destroys len_in_bytes
126 void C1_MacroAssembler::initialize_body(Register obj, Register len_in_bytes, int hdr_size_in_bytes, Register t1) {
127 assert(hdr_size_in_bytes >= 0, "header size must be positive or 0");
128 Label done;
129
130 // len_in_bytes is positive and ptr sized
131 subptr(len_in_bytes, hdr_size_in_bytes);
132 zero_memory(obj, len_in_bytes, hdr_size_in_bytes, t1);
133 bind(done);
134 }
135
136
137 void C1_MacroAssembler::allocate_object(Register obj, Register t1, Register t2, int header_size, int object_size, Register klass, Label& slow_case) {
138 assert(obj == rax, "obj must be in rax, for cmpxchg");
139 assert_different_registers(obj, t1, t2); // XXX really?
140 assert(header_size >= 0 && object_size >= header_size, "illegal sizes");
141
142 try_allocate(obj, noreg, object_size * BytesPerWord, t1, t2, slow_case);
143
144 initialize_object(obj, klass, noreg, object_size * HeapWordSize, t1, t2, UseTLAB);
145 }
146
147 void C1_MacroAssembler::initialize_object(Register obj, Register klass, Register var_size_in_bytes, int con_size_in_bytes, Register t1, Register t2, bool is_tlab_allocated) {
148 assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0,
149 "con_size_in_bytes is not multiple of alignment");
150 const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize;
151 if (UseCompactObjectHeaders) {
152 assert(hdr_size_in_bytes == 8, "check object headers size");
153 }
154 initialize_header(obj, klass, noreg, t1, t2);
155
156 if (!(UseTLAB && ZeroTLAB && is_tlab_allocated)) {
157 // clear rest of allocated space
158 const Register t1_zero = t1;
159 const Register index = t2;
160 const int threshold = 6 * BytesPerWord; // approximate break even point for code size (see comments below)
161 if (var_size_in_bytes != noreg) {
162 mov(index, var_size_in_bytes);
163 initialize_body(obj, index, hdr_size_in_bytes, t1_zero);
164 } else if (con_size_in_bytes <= threshold) {
165 // use explicit null stores
166 // code size = 2 + 3*n bytes (n = number of fields to clear)
167 xorptr(t1_zero, t1_zero); // use t1_zero reg to clear memory (shorter code)
168 for (int i = hdr_size_in_bytes; i < con_size_in_bytes; i += BytesPerWord)
169 movptr(Address(obj, i), t1_zero);
170 } else if (con_size_in_bytes > hdr_size_in_bytes) {
171 // use loop to null out the fields
172 // code size = 16 bytes for even n (n = number of fields to clear)
173 // initialize last object field first if odd number of fields
174 xorptr(t1_zero, t1_zero); // use t1_zero reg to clear memory (shorter code)
175 movptr(index, (con_size_in_bytes - hdr_size_in_bytes) >> 3);
176 // initialize last object field if constant size is odd
177 if (((con_size_in_bytes - hdr_size_in_bytes) & 4) != 0)
178 movptr(Address(obj, con_size_in_bytes - (1*BytesPerWord)), t1_zero);
179 // initialize remaining object fields: rdx is a multiple of 2
180 { Label loop;
181 bind(loop);
182 movptr(Address(obj, index, Address::times_8, hdr_size_in_bytes - (1*BytesPerWord)),
183 t1_zero);
184 decrement(index);
185 jcc(Assembler::notZero, loop);
186 }
187 }
188 }
189
190 if (CURRENT_ENV->dtrace_alloc_probes()) {
191 assert(obj == rax, "must be");
192 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_dtrace_object_alloc_id)));
193 }
194
195 verify_oop(obj);
196 }
197
198 void C1_MacroAssembler::allocate_array(Register obj, Register len, Register t1, Register t2, int base_offset_in_bytes, Address::ScaleFactor f, Register klass, Label& slow_case, bool zero_array) {
199 assert(obj == rax, "obj must be in rax, for cmpxchg");
200 assert_different_registers(obj, len, t1, t2, klass);
201
202 // determine alignment mask
203 assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work");
204
205 // check for negative or excessive length
206 cmpptr(len, checked_cast<int32_t>(max_array_allocation_length));
207 jcc(Assembler::above, slow_case);
208
209 const Register arr_size = t2; // okay to be the same
210 // align object end
211 movptr(arr_size, base_offset_in_bytes + MinObjAlignmentInBytesMask);
212 lea(arr_size, Address(arr_size, len, f));
213 andptr(arr_size, ~MinObjAlignmentInBytesMask);
214
215 try_allocate(obj, arr_size, 0, t1, t2, slow_case);
216
217 initialize_header(obj, klass, len, t1, t2);
218
219 // clear rest of allocated space
220 if (zero_array) {
221 const Register len_zero = len;
222 // Align-up to word boundary, because we clear the 4 bytes potentially
223 // following the length field in initialize_header().
224 int base_offset = align_up(base_offset_in_bytes, BytesPerWord);
225 initialize_body(obj, arr_size, base_offset, len_zero);
226 }
227
228 if (CURRENT_ENV->dtrace_alloc_probes()) {
229 assert(obj == rax, "must be");
230 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_dtrace_object_alloc_id)));
231 }
232
233 verify_oop(obj);
234 }
235
236 void C1_MacroAssembler::build_frame_helper(int frame_size_in_bytes, int sp_offset_for_orig_pc, int sp_inc, bool reset_orig_pc, bool needs_stack_repair) {
237 push(rbp);
238 #ifdef ASSERT
239 if (sp_inc > 0) {
240 movl(Address(rsp, 0), badRegWordVal);
241 movl(Address(rsp, VMRegImpl::stack_slot_size), badRegWordVal);
242 }
243 #endif
244 if (PreserveFramePointer) {
245 mov(rbp, rsp);
246 }
247 decrement(rsp, frame_size_in_bytes);
248
249 if (needs_stack_repair) {
250 // Save stack increment (also account for fixed framesize and rbp)
251 assert((sp_inc & (StackAlignmentInBytes-1)) == 0, "stack increment not aligned");
252 int real_frame_size = sp_inc + frame_size_in_bytes;
253 movptr(Address(rsp, frame_size_in_bytes - wordSize), real_frame_size);
254 }
255 if (reset_orig_pc) {
256 // Zero orig_pc to detect deoptimization during buffering in the entry points
257 movptr(Address(rsp, sp_offset_for_orig_pc), 0);
258 }
259 }
260
261 void C1_MacroAssembler::build_frame(int frame_size_in_bytes, int bang_size_in_bytes, int sp_offset_for_orig_pc, bool needs_stack_repair, bool has_scalarized_args, Label* verified_inline_entry_label) {
262 // Make sure there is enough stack space for this method's activation.
263 // Note that we do this before doing an enter(). This matches the
264 // ordering of C2's stack overflow check / rsp decrement and allows
265 // the SharedRuntime stack overflow handling to be consistent
266 // between the two compilers.
267 assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
268 generate_stack_overflow_check(bang_size_in_bytes);
269
270 build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, 0, has_scalarized_args, needs_stack_repair);
271
272 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
273 // C1 code is not hot enough to micro optimize the nmethod entry barrier with an out-of-line stub
274 bs->nmethod_entry_barrier(this, nullptr /* slow_path */, nullptr /* continuation */);
275
276 if (verified_inline_entry_label != nullptr) {
277 // Jump here from the scalarized entry points that already created the frame.
278 bind(*verified_inline_entry_label);
279 }
280 }
281
282 void C1_MacroAssembler::verified_entry(bool breakAtEntry) {
283 if (breakAtEntry) int3();
284 // build frame
285 }
286
287 int C1_MacroAssembler::scalarized_entry(const CompiledEntrySignature* ces, int frame_size_in_bytes, int bang_size_in_bytes, int sp_offset_for_orig_pc, Label& verified_inline_entry_label, bool is_inline_ro_entry) {
288 assert(InlineTypePassFieldsAsArgs, "sanity");
289 // Make sure there is enough stack space for this method's activation.
290 assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
291 generate_stack_overflow_check(bang_size_in_bytes);
292
293 GrowableArray<SigEntry>* sig = ces->sig();
294 GrowableArray<SigEntry>* sig_cc = is_inline_ro_entry ? ces->sig_cc_ro() : ces->sig_cc();
295 VMRegPair* regs = ces->regs();
296 VMRegPair* regs_cc = is_inline_ro_entry ? ces->regs_cc_ro() : ces->regs_cc();
297 int args_on_stack = ces->args_on_stack();
298 int args_on_stack_cc = is_inline_ro_entry ? ces->args_on_stack_cc_ro() : ces->args_on_stack_cc();
299
300 assert(sig->length() <= sig_cc->length(), "Zero-sized inline class not allowed!");
301 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sig_cc->length());
302 int args_passed = sig->length();
303 int args_passed_cc = SigEntry::fill_sig_bt(sig_cc, sig_bt);
304
305 // Create a temp frame so we can call into the runtime. It must be properly set up to accommodate GC.
306 build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, 0, true, ces->c1_needs_stack_repair());
307
308 // The runtime call might safepoint, make sure nmethod entry barrier is executed
309 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
310 // C1 code is not hot enough to micro optimize the nmethod entry barrier with an out-of-line stub
311 bs->nmethod_entry_barrier(this, nullptr /* slow_path */, nullptr /* continuation */);
312
313 // FIXME -- call runtime only if we cannot in-line allocate all the incoming inline type args.
314 movptr(rbx, (intptr_t)(ces->method()));
315 if (is_inline_ro_entry) {
316 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_buffer_inline_args_no_receiver_id)));
317 } else {
318 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_buffer_inline_args_id)));
319 }
320 int rt_call_offset = offset();
321
322 // Remove the temp frame
323 addptr(rsp, frame_size_in_bytes);
324 pop(rbp);
325
326 // Check if we need to extend the stack for packing
327 int sp_inc = 0;
328 if (args_on_stack > args_on_stack_cc) {
329 sp_inc = extend_stack_for_inline_args(args_on_stack);
330 }
331
332 shuffle_inline_args(true, is_inline_ro_entry, sig_cc,
333 args_passed_cc, args_on_stack_cc, regs_cc, // from
334 args_passed, args_on_stack, regs, // to
335 sp_inc, rax);
336
337 // Create the real frame. Below jump will then skip over the stack banging and frame
338 // setup code in the verified_inline_entry (which has a different real_frame_size).
339 build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, sp_inc, false, ces->c1_needs_stack_repair());
340
341 jmp(verified_inline_entry_label);
342 return rt_call_offset;
343 }
344
345 void C1_MacroAssembler::load_parameter(int offset_in_words, Register reg) {
346 // rbp, + 0: link
347 // + 1: return address
348 // + 2: argument with offset 0
349 // + 3: argument with offset 1
350 // + 4: ...
351
352 movptr(reg, Address(rbp, (offset_in_words + 2) * BytesPerWord));
353 }
354
355 #ifndef PRODUCT
356
357 void C1_MacroAssembler::verify_stack_oop(int stack_offset) {
358 if (!VerifyOops) return;
359 verify_oop_addr(Address(rsp, stack_offset));
360 }
361
362 void C1_MacroAssembler::verify_not_null_oop(Register r) {
363 if (!VerifyOops) return;
364 Label not_null;
365 testptr(r, r);
366 jcc(Assembler::notZero, not_null);
367 stop("non-null oop required");
368 bind(not_null);
369 verify_oop(r);
370 }
371
372 void C1_MacroAssembler::invalidate_registers(bool inv_rax, bool inv_rbx, bool inv_rcx, bool inv_rdx, bool inv_rsi, bool inv_rdi) {
373 #ifdef ASSERT
374 if (inv_rax) movptr(rax, 0xDEAD);
375 if (inv_rbx) movptr(rbx, 0xDEAD);
376 if (inv_rcx) movptr(rcx, 0xDEAD);
377 if (inv_rdx) movptr(rdx, 0xDEAD);
378 if (inv_rsi) movptr(rsi, 0xDEAD);
379 if (inv_rdi) movptr(rdi, 0xDEAD);
380 #endif
381 }
382
383 #endif // ifndef PRODUCT