1 /*
2 * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2016, 2024 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 "asm/macroAssembler.inline.hpp"
27 #include "c1/c1_MacroAssembler.hpp"
28 #include "c1/c1_Runtime1.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/os.hpp"
38 #include "runtime/sharedRuntime.hpp"
39 #include "runtime/stubRoutines.hpp"
40 #include "utilities/macros.hpp"
41
42 void C1_MacroAssembler::explicit_null_check(Register base) {
43 ShouldNotCallThis(); // unused
44 }
45
46 void C1_MacroAssembler::build_frame(int frame_size_in_bytes, int bang_size_in_bytes,
47 int sp_offset_for_orig_pc,
48 bool needs_stack_repair, bool has_scalarized_args,
49 Label* verified_inline_entry_label) {
50 assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect");
51 generate_stack_overflow_check(bang_size_in_bytes);
52 save_return_pc();
53 push_frame(frame_size_in_bytes);
54
55 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
56 bs->nmethod_entry_barrier(this);
57 }
58
59 void C1_MacroAssembler::verified_entry(bool breakAtEntry) {
60 if (breakAtEntry) z_illtrap(0xC1);
61 }
62
63 void C1_MacroAssembler::lock_object(Register Rmark, Register Roop, Register Rbox, Label& slow_case) {
64 const Register tmp = Z_R1_scratch;
65
66 assert_different_registers(Rmark, Roop, Rbox, tmp);
67
68 verify_oop(Roop, FILE_AND_LINE);
69
70 // Save object being locked into the BasicObjectLock...
71 z_stg(Roop, Address(Rbox, BasicObjectLock::obj_offset()));
72
73 fast_lock(Rbox, Roop, Rmark, tmp, slow_case);
74 }
75
76 void C1_MacroAssembler::unlock_object(Register Rmark, Register Roop, Register Rbox, Label& slow_case) {
77 assert_different_registers(Rmark, Roop, Rbox);
78
79 // Load object.
80 z_lg(Roop, Address(Rbox, BasicObjectLock::obj_offset()));
81 verify_oop(Roop, FILE_AND_LINE);
82
83 fast_unlock(Roop, Rmark, Z_R1_scratch, slow_case);
84 }
85
86 void C1_MacroAssembler::try_allocate(
87 Register obj, // result: Pointer to object after successful allocation.
88 Register var_size_in_bytes, // Object size in bytes if unknown at compile time; invalid otherwise.
89 int con_size_in_bytes, // Object size in bytes if known at compile time.
90 Register t1, // Temp register.
91 Label& slow_case // Continuation point if fast allocation fails.
92 ) {
93 if (UseTLAB) {
94 tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, slow_case);
95 } else {
96 // Allocation in shared Eden not implemented, because sapjvm allocation trace does not allow it.
97 z_brul(slow_case);
98 }
99 }
100
101 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register Rzero, Register t1) {
102 assert_different_registers(obj, klass, len, t1, Rzero);
103 if (UseCompactObjectHeaders) {
104 z_lg(t1, Address(klass, in_bytes(Klass::prototype_header_offset())));
105 z_stg(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
106 } else {
107 load_const_optimized(t1, (intx)markWord::prototype().value());
108 z_stg(t1, Address(obj, oopDesc::mark_offset_in_bytes()));
109 store_klass(klass, obj, t1);
110 }
111
112 if (len->is_valid()) {
113 // Length will be in the klass gap.
114 z_st(len, Address(obj, arrayOopDesc::length_offset_in_bytes()));
115 } else if (!UseCompactObjectHeaders) {
116 store_klass_gap(Rzero, obj); // Zero klass gap.
117 }
118 }
119
120 void C1_MacroAssembler::initialize_body(Register objectFields, Register len_in_bytes, Register Rzero) {
121 assert_different_registers(objectFields, len_in_bytes, Rzero);
122
123 // Initialize object fields.
124 // See documentation for MVCLE instruction!!!
125 assert(objectFields->encoding()%2==0, "objectFields must be an even register");
126 assert(len_in_bytes->encoding() == (objectFields->encoding()+1), "objectFields and len_in_bytes must be a register pair");
127 assert(Rzero->encoding()%2==1, "Rzero must be an odd register");
128
129 // Use Rzero as src length, then mvcle will copy nothing
130 // and fill the object with the padding value 0.
131 move_long_ext(objectFields, as_Register(Rzero->encoding()-1), 0);
132 }
133
134 void C1_MacroAssembler::allocate_object(
135 Register obj, // Result: pointer to object after successful allocation.
136 Register t1, // temp register
137 Register t2, // temp register: Must be a global register for try_allocate.
138 int hdr_size, // object header size in words
139 int obj_size, // object size in words
140 Register klass, // object klass
141 Label& slow_case // Continuation point if fast allocation fails.
142 ) {
143 assert_different_registers(obj, t1, t2, klass);
144
145 // Allocate space and initialize header.
146 try_allocate(obj, noreg, obj_size * wordSize, t1, slow_case);
147
148 initialize_object(obj, klass, noreg, obj_size * HeapWordSize, t1, t2);
149 }
150
151 void C1_MacroAssembler::initialize_object(
152 Register obj, // result: Pointer to object after successful allocation.
153 Register klass, // object klass
154 Register var_size_in_bytes, // Object size in bytes if unknown at compile time; invalid otherwise.
155 int con_size_in_bytes, // Object size in bytes if known at compile time.
156 Register t1, // temp register
157 Register t2 // temp register
158 ) {
159 assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0,
160 "con_size_in_bytes is not multiple of alignment");
161 assert(var_size_in_bytes == noreg, "not implemented");
162 const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize;
163
164 const Register Rzero = t2;
165
166 z_xgr(Rzero, Rzero);
167 initialize_header(obj, klass, noreg, Rzero, t1);
168
169 // Clear rest of allocated space.
170 const int threshold = 4 * BytesPerWord;
171 if (con_size_in_bytes <= threshold) {
172 // Use explicit null stores.
173 // code size = 6*n bytes (n = number of fields to clear)
174 for (int i = hdr_size_in_bytes; i < con_size_in_bytes; i += BytesPerWord)
175 z_stg(Rzero, Address(obj, i));
176 } else {
177 // Code size generated by initialize_body() is 16.
178 Register object_fields = Z_R0_scratch;
179 Register len_in_bytes = Z_R1_scratch;
180 z_la(object_fields, hdr_size_in_bytes, obj);
181 load_const_optimized(len_in_bytes, con_size_in_bytes - hdr_size_in_bytes);
182 initialize_body(object_fields, len_in_bytes, Rzero);
183 }
184
185 // Dtrace support is unimplemented.
186 // if (CURRENT_ENV->dtrace_alloc_probes()) {
187 // assert(obj == rax, "must be");
188 // call(RuntimeAddress(Runtime1::entry_for (StubId::c1_dtrace_object_alloc_id)));
189 // }
190
191 verify_oop(obj, FILE_AND_LINE);
192 }
193
194 void C1_MacroAssembler::allocate_array(
195 Register obj, // result: Pointer to array after successful allocation.
196 Register len, // array length
197 Register t1, // temp register
198 Register t2, // temp register
199 int base_offset_in_bytes, // elements offset in bytes
200 int elt_size, // element size in bytes
201 Register klass, // object klass
202 Label& slow_case, // Continuation point if fast allocation fails.
203 bool zero_array // zero the allocated array or not
204 ) {
205 assert_different_registers(obj, len, t1, t2, klass);
206
207 // Determine alignment mask.
208 assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work");
209
210 // Check for negative or excessive length.
211 compareU64_and_branch(len, (int32_t)max_array_allocation_length, bcondHigh, slow_case);
212
213 // Compute array size.
214 // Note: If 0 <= len <= max_length, len*elt_size + header + alignment is
215 // smaller or equal to the largest integer. Also, since top is always
216 // aligned, we can do the alignment here instead of at the end address
217 // computation.
218 const Register arr_size = t2;
219 switch (elt_size) {
220 case 1: lgr_if_needed(arr_size, len); break;
221 case 2: z_sllg(arr_size, len, 1); break;
222 case 4: z_sllg(arr_size, len, 2); break;
223 case 8: z_sllg(arr_size, len, 3); break;
224 default: ShouldNotReachHere();
225 }
226 add2reg(arr_size, base_offset_in_bytes + MinObjAlignmentInBytesMask); // Add space for header & alignment.
227 z_nill(arr_size, (~MinObjAlignmentInBytesMask) & 0xffff); // Align array size.
228
229 try_allocate(obj, arr_size, 0, t1, slow_case);
230
231 initialize_header(obj, klass, len, noreg, t1);
232
233 // Clear rest of allocated space.
234 if (zero_array) {
235 Label done;
236 Register object_fields = t1;
237 Register Rzero = Z_R1_scratch;
238 z_aghi(arr_size, -base_offset_in_bytes);
239 z_bre(done); // Jump if size of fields is zero.
240 z_la(object_fields, base_offset_in_bytes, obj);
241 z_xgr(Rzero, Rzero);
242 initialize_body(object_fields, arr_size, Rzero);
243 bind(done);
244 }
245
246 // Dtrace support is unimplemented.
247 // if (CURRENT_ENV->dtrace_alloc_probes()) {
248 // assert(obj == rax, "must be");
249 // call(RuntimeAddress(Runtime1::entry_for (StubId::c1_dtrace_object_alloc_id)));
250 // }
251
252 verify_oop(obj, FILE_AND_LINE);
253 }
254
255 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) {
256 Unimplemented();
257 }
258
259
260
261 #ifndef PRODUCT
262
263 void C1_MacroAssembler::verify_stack_oop(int stack_offset) {
264 if (!VerifyOops) return;
265 verify_oop_addr(Address(Z_SP, stack_offset), FILE_AND_LINE);
266 }
267
268 void C1_MacroAssembler::verify_not_null_oop(Register r) {
269 if (!VerifyOops) return;
270 NearLabel not_null;
271 compareU64_and_branch(r, (intptr_t)0, bcondNotEqual, not_null);
272 stop("non-null oop required");
273 bind(not_null);
274 verify_oop(r, FILE_AND_LINE);
275 }
276
277 void C1_MacroAssembler::invalidate_registers(Register preserve1,
278 Register preserve2,
279 Register preserve3) {
280 Register dead_value = noreg;
281 for (int i = 0; i < FrameMap::nof_cpu_regs; i++) {
282 Register r = as_Register(i);
283 if (r != preserve1 && r != preserve2 && r != preserve3 && r != Z_SP && r != Z_thread) {
284 if (dead_value == noreg) {
285 load_const_optimized(r, 0xc1dead);
286 dead_value = r;
287 } else {
288 z_lgr(r, dead_value);
289 }
290 }
291 }
292 }
293
294 #endif // !PRODUCT