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.
22 *
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/basicLock.hpp"
37 #include "runtime/frame.inline.hpp"
38 #include "runtime/globals.hpp"
39 #include "runtime/os.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/stubRoutines.hpp"
42 #include "utilities/checkedCast.hpp"
43 #include "utilities/globalDefinitions.hpp"
44
45 int C1_MacroAssembler::lock_object(Register hdr, Register obj, Register disp_hdr, Register tmp, Label& slow_case) {
46 assert(hdr == rax, "hdr must be rax, for the cmpxchg instruction");
47 assert_different_registers(hdr, obj, disp_hdr, tmp);
48 int null_check_offset = -1;
49
50 verify_oop(obj);
51
52 // save object being locked into the BasicObjectLock
53 movptr(Address(disp_hdr, BasicObjectLock::obj_offset()), obj);
54
55 null_check_offset = offset();
56
57 lightweight_lock(disp_hdr, obj, hdr, tmp, slow_case);
58
59 return null_check_offset;
60 }
61
62 void C1_MacroAssembler::unlock_object(Register hdr, Register obj, Register disp_hdr, Label& slow_case) {
63 assert(disp_hdr == rax, "disp_hdr must be rax, for the cmpxchg instruction");
64 assert(hdr != obj && hdr != disp_hdr && obj != disp_hdr, "registers must be different");
65
66 // load object
67 movptr(obj, Address(disp_hdr, BasicObjectLock::obj_offset()));
68 verify_oop(obj);
69
70 lightweight_unlock(obj, disp_hdr, hdr, slow_case);
71 }
72
73
74 // Defines obj, preserves var_size_in_bytes
75 void C1_MacroAssembler::try_allocate(Register obj, Register var_size_in_bytes, int con_size_in_bytes, Register t1, Register t2, Label& slow_case) {
76 if (UseTLAB) {
77 tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case);
78 } else {
79 jmp(slow_case);
80 }
81 }
82
83
84 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
85 assert_different_registers(obj, klass, len, t1, t2);
86 if (UseCompactObjectHeaders || EnableValhalla) {
87 // COH: Markword contains class pointer which is only known at runtime.
88 // Valhalla: Could have value class which has a different prototype header to a normal object.
89 // In both cases, we need to fetch dynamically.
90 movptr(t1, Address(klass, Klass::prototype_header_offset()));
91 movptr(Address(obj, oopDesc::mark_offset_in_bytes()), t1);
92 } else {
93 // Otherwise: Can use the statically computed prototype header which is the same for every object.
94 movptr(Address(obj, oopDesc::mark_offset_in_bytes()), checked_cast<int32_t>(markWord::prototype().value()));
95 }
96 if (!UseCompactObjectHeaders) {
97 // COH: Markword already contains class pointer. Nothing else to do.
98 // Otherwise: Fetch klass pointer following the markword
99 if (UseCompressedClassPointers) { // Take care not to kill klass
100 movptr(t1, klass);
101 encode_klass_not_null(t1, rscratch1);
102 movl(Address(obj, oopDesc::klass_offset_in_bytes()), t1);
103 } else {
104 movptr(Address(obj, oopDesc::klass_offset_in_bytes()), klass);
105 }
106 }
107
108 if (len->is_valid()) {
109 movl(Address(obj, arrayOopDesc::length_offset_in_bytes()), len);
110 int base_offset = arrayOopDesc::length_offset_in_bytes() + BytesPerInt;
111 if (!is_aligned(base_offset, BytesPerWord)) {
112 assert(is_aligned(base_offset, BytesPerInt), "must be 4-byte aligned");
113 // Clear gap/first 4 bytes following the length field.
114 xorl(t1, t1);
115 movl(Address(obj, base_offset), t1);
116 }
117 } else if (UseCompressedClassPointers && !UseCompactObjectHeaders) {
118 xorptr(t1, t1);
119 store_klass_gap(obj, t1);
120 }
121 }
122
123
124 // preserves obj, destroys len_in_bytes
125 void C1_MacroAssembler::initialize_body(Register obj, Register len_in_bytes, int hdr_size_in_bytes, Register t1) {
126 assert(hdr_size_in_bytes >= 0, "header size must be positive or 0");
127 Label done;
128
129 // len_in_bytes is positive and ptr sized
130 subptr(len_in_bytes, hdr_size_in_bytes);
131 zero_memory(obj, len_in_bytes, hdr_size_in_bytes, t1);
132 bind(done);
133 }
134
135
136 void C1_MacroAssembler::allocate_object(Register obj, Register t1, Register t2, int header_size, int object_size, Register klass, Label& slow_case) {
137 assert(obj == rax, "obj must be in rax, for cmpxchg");
138 assert_different_registers(obj, t1, t2); // XXX really?
139 assert(header_size >= 0 && object_size >= header_size, "illegal sizes");
140
141 try_allocate(obj, noreg, object_size * BytesPerWord, t1, t2, slow_case);
142
143 initialize_object(obj, klass, noreg, object_size * HeapWordSize, t1, t2, UseTLAB);
144 }
145
146 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) {
147 assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0,
148 "con_size_in_bytes is not multiple of alignment");
149 const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize;
150 if (UseCompactObjectHeaders) {
151 assert(hdr_size_in_bytes == 8, "check object headers size");
152 }
153 initialize_header(obj, klass, noreg, t1, t2);
154
155 if (!(UseTLAB && ZeroTLAB && is_tlab_allocated)) {
156 // clear rest of allocated space
157 const Register t1_zero = t1;
158 const Register index = t2;
159 const int threshold = 6 * BytesPerWord; // approximate break even point for code size (see comments below)
160 if (var_size_in_bytes != noreg) {
161 mov(index, var_size_in_bytes);
162 initialize_body(obj, index, hdr_size_in_bytes, t1_zero);
163 } else if (con_size_in_bytes <= threshold) {
164 // use explicit null stores
165 // code size = 2 + 3*n bytes (n = number of fields to clear)
166 xorptr(t1_zero, t1_zero); // use t1_zero reg to clear memory (shorter code)
167 for (int i = hdr_size_in_bytes; i < con_size_in_bytes; i += BytesPerWord)
168 movptr(Address(obj, i), t1_zero);
169 } else if (con_size_in_bytes > hdr_size_in_bytes) {
170 // use loop to null out the fields
171 // code size = 16 bytes for even n (n = number of fields to clear)
172 // initialize last object field first if odd number of fields
173 xorptr(t1_zero, t1_zero); // use t1_zero reg to clear memory (shorter code)
174 movptr(index, (con_size_in_bytes - hdr_size_in_bytes) >> 3);
175 // initialize last object field if constant size is odd
176 if (((con_size_in_bytes - hdr_size_in_bytes) & 4) != 0)
177 movptr(Address(obj, con_size_in_bytes - (1*BytesPerWord)), t1_zero);
178 // initialize remaining object fields: rdx is a multiple of 2
179 { Label loop;
180 bind(loop);
181 movptr(Address(obj, index, Address::times_8, hdr_size_in_bytes - (1*BytesPerWord)),
182 t1_zero);
183 decrement(index);
184 jcc(Assembler::notZero, loop);
185 }
186 }
187 }
188
189 if (CURRENT_ENV->dtrace_alloc_probes()) {
190 assert(obj == rax, "must be");
191 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_dtrace_object_alloc_id)));
192 }
193
194 verify_oop(obj);
195 }
196
197 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) {
198 assert(obj == rax, "obj must be in rax, for cmpxchg");
199 assert_different_registers(obj, len, t1, t2, klass);
200
201 // determine alignment mask
202 assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work");
203
204 // check for negative or excessive length
205 cmpptr(len, checked_cast<int32_t>(max_array_allocation_length));
206 jcc(Assembler::above, slow_case);
207
208 const Register arr_size = t2; // okay to be the same
209 // align object end
210 movptr(arr_size, base_offset_in_bytes + MinObjAlignmentInBytesMask);
211 lea(arr_size, Address(arr_size, len, f));
212 andptr(arr_size, ~MinObjAlignmentInBytesMask);
213
214 try_allocate(obj, arr_size, 0, t1, t2, slow_case);
215
216 initialize_header(obj, klass, len, t1, t2);
217
218 // clear rest of allocated space
219 if (zero_array) {
220 const Register len_zero = len;
221 // Align-up to word boundary, because we clear the 4 bytes potentially
222 // following the length field in initialize_header().
223 int base_offset = align_up(base_offset_in_bytes, BytesPerWord);
224 initialize_body(obj, arr_size, base_offset, len_zero);
225 }
226
227 if (CURRENT_ENV->dtrace_alloc_probes()) {
228 assert(obj == rax, "must be");
229 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_dtrace_object_alloc_id)));
230 }
231
232 verify_oop(obj);
233 }
234
235 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) {
236 push(rbp);
237 if (PreserveFramePointer) {
238 mov(rbp, rsp);
239 }
240 decrement(rsp, frame_size_in_bytes);
241
242 if (needs_stack_repair) {
243 // Save stack increment (also account for fixed framesize and rbp)
244 assert((sp_inc & (StackAlignmentInBytes-1)) == 0, "stack increment not aligned");
245 int real_frame_size = sp_inc + frame_size_in_bytes + wordSize;
246 movptr(Address(rsp, frame_size_in_bytes - wordSize), real_frame_size);
247 }
248 if (reset_orig_pc) {
249 // Zero orig_pc to detect deoptimization during buffering in the entry points
250 movptr(Address(rsp, sp_offset_for_orig_pc), 0);
251 }
252 }
253
254 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) {
255 // Make sure there is enough stack space for this method's activation.
256 // Note that we do this before doing an enter(). This matches the
257 // ordering of C2's stack overflow check / rsp decrement and allows
258 // the SharedRuntime stack overflow handling to be consistent
259 // between the two compilers.
260 assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
261 generate_stack_overflow_check(bang_size_in_bytes);
262
263 build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, 0, has_scalarized_args, needs_stack_repair);
264
265 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
266 // C1 code is not hot enough to micro optimize the nmethod entry barrier with an out-of-line stub
267 bs->nmethod_entry_barrier(this, nullptr /* slow_path */, nullptr /* continuation */);
268
269 if (verified_inline_entry_label != nullptr) {
270 // Jump here from the scalarized entry points that already created the frame.
271 bind(*verified_inline_entry_label);
272 }
273 }
274
275 void C1_MacroAssembler::verified_entry(bool breakAtEntry) {
276 if (breakAtEntry) int3();
277 // build frame
278 }
279
280 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) {
281 assert(InlineTypePassFieldsAsArgs, "sanity");
282 // Make sure there is enough stack space for this method's activation.
283 assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
284 generate_stack_overflow_check(bang_size_in_bytes);
285
286 GrowableArray<SigEntry>* sig = ces->sig();
287 GrowableArray<SigEntry>* sig_cc = is_inline_ro_entry ? ces->sig_cc_ro() : ces->sig_cc();
288 VMRegPair* regs = ces->regs();
289 VMRegPair* regs_cc = is_inline_ro_entry ? ces->regs_cc_ro() : ces->regs_cc();
290 int args_on_stack = ces->args_on_stack();
291 int args_on_stack_cc = is_inline_ro_entry ? ces->args_on_stack_cc_ro() : ces->args_on_stack_cc();
292
293 assert(sig->length() <= sig_cc->length(), "Zero-sized inline class not allowed!");
294 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sig_cc->length());
295 int args_passed = sig->length();
296 int args_passed_cc = SigEntry::fill_sig_bt(sig_cc, sig_bt);
297
298 // Create a temp frame so we can call into the runtime. It must be properly set up to accommodate GC.
299 build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, 0, true, ces->c1_needs_stack_repair());
300
301 // The runtime call might safepoint, make sure nmethod entry barrier is executed
302 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
303 // C1 code is not hot enough to micro optimize the nmethod entry barrier with an out-of-line stub
304 bs->nmethod_entry_barrier(this, nullptr /* slow_path */, nullptr /* continuation */);
305
306 // FIXME -- call runtime only if we cannot in-line allocate all the incoming inline type args.
307 movptr(rbx, (intptr_t)(ces->method()));
308 if (is_inline_ro_entry) {
309 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_buffer_inline_args_no_receiver_id)));
310 } else {
311 call(RuntimeAddress(Runtime1::entry_for(StubId::c1_buffer_inline_args_id)));
312 }
313 int rt_call_offset = offset();
314
315 // Remove the temp frame
316 addptr(rsp, frame_size_in_bytes);
317 pop(rbp);
318
319 // Check if we need to extend the stack for packing
320 int sp_inc = 0;
321 if (args_on_stack > args_on_stack_cc) {
322 sp_inc = extend_stack_for_inline_args(args_on_stack);
323 }
324
325 shuffle_inline_args(true, is_inline_ro_entry, sig_cc,
326 args_passed_cc, args_on_stack_cc, regs_cc, // from
327 args_passed, args_on_stack, regs, // to
328 sp_inc, rax);
329
330 // Create the real frame. Below jump will then skip over the stack banging and frame
331 // setup code in the verified_inline_entry (which has a different real_frame_size).
332 build_frame_helper(frame_size_in_bytes, sp_offset_for_orig_pc, sp_inc, false, ces->c1_needs_stack_repair());
333
334 jmp(verified_inline_entry_label);
335 return rt_call_offset;
336 }
337
338 void C1_MacroAssembler::load_parameter(int offset_in_words, Register reg) {
339 // rbp, + 0: link
340 // + 1: return address
341 // + 2: argument with offset 0
342 // + 3: argument with offset 1
343 // + 4: ...
344
345 movptr(reg, Address(rbp, (offset_in_words + 2) * BytesPerWord));
346 }
347
348 #ifndef PRODUCT
349
350 void C1_MacroAssembler::verify_stack_oop(int stack_offset) {
351 if (!VerifyOops) return;
352 verify_oop_addr(Address(rsp, stack_offset));
353 }
354
355 void C1_MacroAssembler::verify_not_null_oop(Register r) {
356 if (!VerifyOops) return;
357 Label not_null;
358 testptr(r, r);
359 jcc(Assembler::notZero, not_null);
360 stop("non-null oop required");
361 bind(not_null);
362 verify_oop(r);
363 }
364
365 void C1_MacroAssembler::invalidate_registers(bool inv_rax, bool inv_rbx, bool inv_rcx, bool inv_rdx, bool inv_rsi, bool inv_rdi) {
366 #ifdef ASSERT
367 if (inv_rax) movptr(rax, 0xDEAD);
368 if (inv_rbx) movptr(rbx, 0xDEAD);
369 if (inv_rcx) movptr(rcx, 0xDEAD);
370 if (inv_rdx) movptr(rdx, 0xDEAD);
371 if (inv_rsi) movptr(rsi, 0xDEAD);
372 if (inv_rdi) movptr(rdi, 0xDEAD);
373 #endif
374 }
375
376 #endif // ifndef PRODUCT