1 /*
2 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, 2021, 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 "c1/c1_MacroAssembler.hpp"
27 #include "c1/c1_Runtime1.hpp"
28 #include "gc/shared/barrierSetAssembler.hpp"
29 #include "gc/shared/collectedHeap.hpp"
30 #include "gc/shared/tlab_globals.hpp"
31 #include "interpreter/interpreter.hpp"
32 #include "oops/arrayOop.hpp"
33 #include "oops/markWord.hpp"
34 #include "runtime/basicLock.hpp"
35 #include "runtime/os.hpp"
36 #include "runtime/sharedRuntime.hpp"
37 #include "runtime/stubRoutines.hpp"
38
39 void C1_MacroAssembler::float_cmp(bool is_float, int unordered_result,
40 FloatRegister f0, FloatRegister f1,
41 Register result)
42 {
43 Label done;
44 if (is_float) {
45 fcmps(f0, f1);
46 } else {
47 fcmpd(f0, f1);
48 }
49 if (unordered_result < 0) {
50 // we want -1 for unordered or less than, 0 for equal and 1 for
51 // greater than.
52 cset(result, NE); // Not equal or unordered
53 cneg(result, result, LT); // Less than or unordered
54 } else {
55 // we want -1 for less than, 0 for equal and 1 for unordered or
56 // greater than.
57 cset(result, NE); // Not equal or unordered
58 cneg(result, result, LO); // Less than
59 }
60 }
61
62 int C1_MacroAssembler::lock_object(Register hdr, Register obj, Register disp_hdr, Register temp, Label& slow_case) {
63 assert_different_registers(hdr, obj, disp_hdr, temp, rscratch2);
64 int null_check_offset = -1;
65
66 verify_oop(obj);
67
68 // save object being locked into the BasicObjectLock
69 str(obj, Address(disp_hdr, BasicObjectLock::obj_offset()));
70
71 null_check_offset = offset();
72
73 lightweight_lock(disp_hdr, obj, hdr, temp, rscratch2, slow_case);
74
75 return null_check_offset;
76 }
77
78
79 void C1_MacroAssembler::unlock_object(Register hdr, Register obj, Register disp_hdr, Register temp, Label& slow_case) {
80 assert_different_registers(hdr, obj, disp_hdr, temp, rscratch2);
81
82 // load object
83 ldr(obj, Address(disp_hdr, BasicObjectLock::obj_offset()));
84 verify_oop(obj);
85
86 lightweight_unlock(obj, hdr, temp, rscratch2, slow_case);
87 }
88
89
90 // Defines obj, preserves var_size_in_bytes
91 void C1_MacroAssembler::try_allocate(Register obj, Register var_size_in_bytes, int con_size_in_bytes, Register t1, Register t2, Label& slow_case) {
92 if (UseTLAB) {
93 tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case);
94 } else {
95 b(slow_case);
96 }
97 }
98
99 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) {
100 assert_different_registers(obj, klass, len);
101
102 if (UseCompactObjectHeaders) {
103 ldr(t1, Address(klass, Klass::prototype_header_offset()));
104 str(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
105 } else {
106 mov(t1, checked_cast<int32_t>(markWord::prototype().value()));
107 str(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
108 if (UseCompressedClassPointers) { // Take care not to kill klass
109 encode_klass_not_null(t1, klass);
110 strw(t1, Address(obj, oopDesc::klass_offset_in_bytes()));
111 } else {
112 str(klass, Address(obj, oopDesc::klass_offset_in_bytes()));
113 }
114 }
115
116 if (len->is_valid()) {
117 strw(len, Address(obj, arrayOopDesc::length_offset_in_bytes()));
118 int base_offset = arrayOopDesc::length_offset_in_bytes() + BytesPerInt;
119 if (!is_aligned(base_offset, BytesPerWord)) {
120 assert(is_aligned(base_offset, BytesPerInt), "must be 4-byte aligned");
121 // Clear gap/first 4 bytes following the length field.
122 strw(zr, Address(obj, base_offset));
123 }
124 } else if (UseCompressedClassPointers && !UseCompactObjectHeaders) {
125 store_klass_gap(obj, zr);
126 }
127 }
128
129 // preserves obj, destroys len_in_bytes
130 //
131 // Scratch registers: t1 = r10, t2 = r11
132 //
133 void C1_MacroAssembler::initialize_body(Register obj, Register len_in_bytes, int hdr_size_in_bytes, Register t1, Register t2) {
134 assert(hdr_size_in_bytes >= 0, "header size must be positive or 0");
135 assert(t1 == r10 && t2 == r11, "must be");
136
137 Label done;
138
139 // len_in_bytes is positive and ptr sized
140 subs(len_in_bytes, len_in_bytes, hdr_size_in_bytes);
141 br(Assembler::EQ, done);
142
143 // zero_words() takes ptr in r10 and count in words in r11
144 mov(rscratch1, len_in_bytes);
145 lea(t1, Address(obj, hdr_size_in_bytes));
146 lsr(t2, rscratch1, LogBytesPerWord);
147 address tpc = zero_words(t1, t2);
148
149 bind(done);
150 if (tpc == nullptr) {
151 Compilation::current()->bailout("no space for trampoline stub");
152 }
153 }
154
155
156 void C1_MacroAssembler::allocate_object(Register obj, Register t1, Register t2, int header_size, int object_size, Register klass, Label& slow_case) {
157 assert_different_registers(obj, t1, t2); // XXX really?
158 assert(header_size >= 0 && object_size >= header_size, "illegal sizes");
159
160 try_allocate(obj, noreg, object_size * BytesPerWord, t1, t2, slow_case);
161
162 initialize_object(obj, klass, noreg, object_size * HeapWordSize, t1, t2, UseTLAB);
163 }
164
165 // Scratch registers: t1 = r10, t2 = r11
166 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) {
167 assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0,
168 "con_size_in_bytes is not multiple of alignment");
169 const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize;
170
171 initialize_header(obj, klass, noreg, t1, t2);
172
173 if (!(UseTLAB && ZeroTLAB && is_tlab_allocated)) {
174 // clear rest of allocated space
175 const Register index = t2;
176 if (var_size_in_bytes != noreg) {
177 mov(index, var_size_in_bytes);
178 initialize_body(obj, index, hdr_size_in_bytes, t1, t2);
179 if (Compilation::current()->bailed_out()) {
180 return;
181 }
182 } else if (con_size_in_bytes > hdr_size_in_bytes) {
183 con_size_in_bytes -= hdr_size_in_bytes;
184 lea(t1, Address(obj, hdr_size_in_bytes));
185 address tpc = zero_words(t1, con_size_in_bytes / BytesPerWord);
186 if (tpc == nullptr) {
187 Compilation::current()->bailout("no space for trampoline stub");
188 return;
189 }
190 }
191 }
192
193 membar(StoreStore);
194
195 if (CURRENT_ENV->dtrace_alloc_probes()) {
196 assert(obj == r0, "must be");
197 far_call(RuntimeAddress(Runtime1::entry_for(StubId::c1_dtrace_object_alloc_id)));
198 }
199
200 verify_oop(obj);
201 }
202 void C1_MacroAssembler::allocate_array(Register obj, Register len, Register t1, Register t2, int base_offset_in_bytes, int f, Register klass, Label& slow_case, bool zero_array) {
203 assert_different_registers(obj, len, t1, t2, klass);
204
205 // determine alignment mask
206 assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work");
207
208 // check for negative or excessive length
209 mov(rscratch1, (int32_t)max_array_allocation_length);
210 cmp(len, rscratch1);
211 br(Assembler::HS, slow_case);
212
213 const Register arr_size = t2; // okay to be the same
214 // align object end
215 mov(arr_size, (int32_t)base_offset_in_bytes + MinObjAlignmentInBytesMask);
216 add(arr_size, arr_size, len, ext::uxtw, f);
217 andr(arr_size, arr_size, ~MinObjAlignmentInBytesMask);
218
219 try_allocate(obj, arr_size, 0, t1, t2, slow_case);
220
221 initialize_header(obj, klass, len, t1, t2);
222
223 // Align-up to word boundary, because we clear the 4 bytes potentially
224 // following the length field in initialize_header().
225 int base_offset = align_up(base_offset_in_bytes, BytesPerWord);
226 // clear rest of allocated space
227 if (zero_array) {
228 initialize_body(obj, arr_size, base_offset, t1, t2);
229 }
230 if (Compilation::current()->bailed_out()) {
231 return;
232 }
233
234 membar(StoreStore);
235
236 if (CURRENT_ENV->dtrace_alloc_probes()) {
237 assert(obj == r0, "must be");
238 far_call(RuntimeAddress(Runtime1::entry_for(StubId::c1_dtrace_object_alloc_id)));
239 }
240
241 verify_oop(obj);
242 }
243
244 void C1_MacroAssembler::build_frame(int framesize, int bang_size_in_bytes) {
245 assert(bang_size_in_bytes >= framesize, "stack bang size incorrect");
246 // Make sure there is enough stack space for this method's activation.
247 // Note that we do this before creating a frame.
248 generate_stack_overflow_check(bang_size_in_bytes);
249 MacroAssembler::build_frame(framesize);
250
251 // Insert nmethod entry barrier into frame.
252 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
253 bs->nmethod_entry_barrier(this, nullptr /* slow_path */, nullptr /* continuation */, nullptr /* guard */);
254 }
255
256 void C1_MacroAssembler::remove_frame(int framesize) {
257 MacroAssembler::remove_frame(framesize);
258 }
259
260
261 void C1_MacroAssembler::verified_entry(bool breakAtEntry) {
262 // If we have to make this method not-entrant we'll overwrite its
263 // first instruction with a jump. For this action to be legal we
264 // must ensure that this first instruction is a B, BL, NOP, BKPT,
265 // SVC, HVC, or SMC. Make it a NOP.
266 nop();
267 }
268
269 void C1_MacroAssembler::load_parameter(int offset_in_words, Register reg) {
270 // rfp, + 0: link
271 // + 1: return address
272 // + 2: argument with offset 0
273 // + 3: argument with offset 1
274 // + 4: ...
275
276 ldr(reg, Address(rfp, (offset_in_words + 2) * BytesPerWord));
277 }
278
279 #ifndef PRODUCT
280
281 void C1_MacroAssembler::verify_stack_oop(int stack_offset) {
282 if (!VerifyOops) return;
283 verify_oop_addr(Address(sp, stack_offset));
284 }
285
286 void C1_MacroAssembler::verify_not_null_oop(Register r) {
287 if (!VerifyOops) return;
288 Label not_null;
289 cbnz(r, not_null);
290 stop("non-null oop required");
291 bind(not_null);
292 verify_oop(r);
293 }
294
295 void C1_MacroAssembler::invalidate_registers(bool inv_r0, bool inv_r19, bool inv_r2, bool inv_r3, bool inv_r4, bool inv_r5) {
296 #ifdef ASSERT
297 static int nn;
298 if (inv_r0) mov(r0, 0xDEAD);
299 if (inv_r19) mov(r19, 0xDEAD);
300 if (inv_r2) mov(r2, nn++);
301 if (inv_r3) mov(r3, 0xDEAD);
302 if (inv_r4) mov(r4, 0xDEAD);
303 if (inv_r5) mov(r5, 0xDEAD);
304 #endif
305 }
306 #endif // ifndef PRODUCT