1 /*
2 * Copyright (c) 2003, 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 #ifdef COMPILER2
26 #include "asm/macroAssembler.hpp"
27 #include "asm/macroAssembler.inline.hpp"
28 #include "code/aotCodeCache.hpp"
29 #include "code/vmreg.hpp"
30 #include "interpreter/interpreter.hpp"
31 #include "opto/runtime.hpp"
32 #include "runtime/sharedRuntime.hpp"
33 #include "runtime/stubRoutines.hpp"
34 #include "runtime/vframeArray.hpp"
35 #include "utilities/globalDefinitions.hpp"
36 #include "vmreg_x86.inline.hpp"
37
38 class SimpleRuntimeFrame {
39
40 public:
41
42 // Most of the runtime stubs have this simple frame layout.
43 // This class exists to make the layout shared in one place.
44 // Offsets are for compiler stack slots, which are jints.
45 enum layout {
46 // The frame sender code expects that rbp will be in the "natural" place and
47 // will override any oopMap setting for it. We must therefore force the layout
48 // so that it agrees with the frame sender code.
49 rbp_off = frame::arg_reg_save_area_bytes/BytesPerInt,
50 rbp_off2,
51 return_off, return_off2,
52 framesize
53 };
54 };
55
56 #define __ masm->
57
58 //------------------------------generate_uncommon_trap_blob--------------------
59 UncommonTrapBlob* OptoRuntime::generate_uncommon_trap_blob() {
60 // Allocate space for the code
61 ResourceMark rm;
62 // Setup code generation tools
63 const char* name = OptoRuntime::stub_name(OptoStubId::uncommon_trap_id);
64 CodeBuffer buffer(name, 2048, 1024);
65 if (buffer.blob() == nullptr) {
66 return nullptr;
67 }
68 MacroAssembler* masm = new MacroAssembler(&buffer);
69
70 assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
71
72 address start = __ pc();
73
74 // Push self-frame. We get here with a return address on the
75 // stack, so rsp is 8-byte aligned until we allocate our frame.
76 __ subptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog!
77
78 // No callee saved registers. rbp is assumed implicitly saved
79 __ movptr(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
80
81 // compiler left unloaded_class_index in j_rarg0 move to where the
82 // runtime expects it.
83 __ movl(c_rarg1, j_rarg0);
84
85 __ set_last_Java_frame(noreg, noreg, nullptr, rscratch1);
86
87 // Call C code. Need thread but NOT official VM entry
88 // crud. We cannot block on this call, no GC can happen. Call should
89 // capture callee-saved registers as well as return values.
90 // Thread is in rdi already.
91 //
92 // UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
93
94 __ mov(c_rarg0, r15_thread);
95 __ movl(c_rarg2, Deoptimization::Unpack_uncommon_trap);
96 __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::uncommon_trap)));
97
98 // Set an oopmap for the call site
99 OopMapSet* oop_maps = new OopMapSet();
100 OopMap* map = new OopMap(SimpleRuntimeFrame::framesize, 0);
101
102 // location of rbp is known implicitly by the frame sender code
103
104 oop_maps->add_gc_map(__ pc() - start, map);
105
106 __ reset_last_Java_frame(false);
107
108 // Load UnrollBlock* into rdi
109 __ mov(rdi, rax);
110
111 #ifdef ASSERT
112 { Label L;
113 __ cmpptr(Address(rdi, Deoptimization::UnrollBlock::unpack_kind_offset()),
114 Deoptimization::Unpack_uncommon_trap);
115 __ jcc(Assembler::equal, L);
116 __ stop("OptoRuntime::generate_uncommon_trap_blob: expected Unpack_uncommon_trap");
117 __ bind(L);
118 }
119 #endif
120
121 // Pop all the frames we must move/replace.
122 //
123 // Frame picture (youngest to oldest)
124 // 1: self-frame (no frame link)
125 // 2: deopting frame (no frame link)
126 // 3: caller of deopting frame (could be compiled/interpreted).
127
128 // Pop self-frame. We have no frame, and must rely only on rax and rsp.
129 __ addptr(rsp, (SimpleRuntimeFrame::framesize - 2) << LogBytesPerInt); // Epilog!
130
131 // Pop deoptimized frame (int)
132 __ movl(rcx, Address(rdi,
133 Deoptimization::UnrollBlock::
134 size_of_deoptimized_frame_offset()));
135 __ addptr(rsp, rcx);
136
137 // rsp should be pointing at the return address to the caller (3)
138
139 // Pick up the initial fp we should save
140 // restore rbp before stack bang because if stack overflow is thrown it needs to be pushed (and preserved)
141 __ movptr(rbp, Address(rdi, Deoptimization::UnrollBlock::initial_info_offset()));
142
143 #ifdef ASSERT
144 // Compilers generate code that bang the stack by as much as the
145 // interpreter would need. So this stack banging should never
146 // trigger a fault. Verify that it does not on non product builds.
147 __ movl(rbx, Address(rdi ,Deoptimization::UnrollBlock::total_frame_sizes_offset()));
148 __ bang_stack_size(rbx, rcx);
149 #endif
150
151 // Load address of array of frame pcs into rcx (address*)
152 __ movptr(rcx, Address(rdi, Deoptimization::UnrollBlock::frame_pcs_offset()));
153
154 // Trash the return pc
155 __ addptr(rsp, wordSize);
156
157 // Load address of array of frame sizes into rsi (intptr_t*)
158 __ movptr(rsi, Address(rdi, Deoptimization::UnrollBlock:: frame_sizes_offset()));
159
160 // Counter
161 __ movl(rdx, Address(rdi, Deoptimization::UnrollBlock:: number_of_frames_offset())); // (int)
162
163 // Now adjust the caller's stack to make up for the extra locals but
164 // record the original sp so that we can save it in the skeletal
165 // interpreter frame and the stack walking of interpreter_sender
166 // will get the unextended sp value and not the "real" sp value.
167
168 const Register sender_sp = r8;
169
170 __ mov(sender_sp, rsp);
171 __ movl(rbx, Address(rdi, Deoptimization::UnrollBlock:: caller_adjustment_offset())); // (int)
172 __ subptr(rsp, rbx);
173
174 // Push interpreter frames in a loop
175 Label loop;
176 __ bind(loop);
177 __ movptr(rbx, Address(rsi, 0)); // Load frame size
178 __ subptr(rbx, 2 * wordSize); // We'll push pc and rbp by hand
179 __ pushptr(Address(rcx, 0)); // Save return address
180 __ enter(); // Save old & set new rbp
181 __ subptr(rsp, rbx); // Prolog
182 __ movptr(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize),
183 sender_sp); // Make it walkable
184 // This value is corrected by layout_activation_impl
185 __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), NULL_WORD);
186 __ mov(sender_sp, rsp); // Pass sender_sp to next frame
187 __ addptr(rsi, wordSize); // Bump array pointer (sizes)
188 __ addptr(rcx, wordSize); // Bump array pointer (pcs)
189 __ decrementl(rdx); // Decrement counter
190 __ jcc(Assembler::notZero, loop);
191 __ pushptr(Address(rcx, 0)); // Save final return address
192
193 // Re-push self-frame
194 __ enter(); // Save old & set new rbp
195 __ subptr(rsp, (SimpleRuntimeFrame::framesize - 4) << LogBytesPerInt);
196 // Prolog
197
198 // Use rbp because the frames look interpreted now
199 // Save "the_pc" since it cannot easily be retrieved using the last_java_SP after we aligned SP.
200 // Don't need the precise return PC here, just precise enough to point into this code blob.
201 address the_pc = __ pc();
202 __ set_last_Java_frame(noreg, rbp, the_pc, rscratch1);
203
204 // Call C code. Need thread but NOT official VM entry
205 // crud. We cannot block on this call, no GC can happen. Call should
206 // restore return values to their stack-slots with the new SP.
207 // Thread is in rdi already.
208 //
209 // BasicType unpack_frames(JavaThread* thread, int exec_mode);
210
211 __ andptr(rsp, -(StackAlignmentInBytes)); // Align SP as required by ABI
212 __ mov(c_rarg0, r15_thread);
213 __ movl(c_rarg1, Deoptimization::Unpack_uncommon_trap);
214 __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
215
216 // Set an oopmap for the call site
217 // Use the same PC we used for the last java frame
218 oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
219
220 // Clear fp AND pc
221 __ reset_last_Java_frame(true);
222
223 // Pop self-frame.
224 __ leave(); // Epilog
225
226 // Jump to interpreter
227 __ ret(0);
228
229 // Make sure all code is generated
230 masm->flush();
231
232 return UncommonTrapBlob::create(&buffer, oop_maps,
233 SimpleRuntimeFrame::framesize >> 1);
234 }
235
236 //------------------------------generate_exception_blob---------------------------
237 // creates exception blob at the end
238 // Using exception blob, this code is jumped from a compiled method.
239 // (see emit_exception_handler in x86_64.ad file)
240 //
241 // Given an exception pc at a call we call into the runtime for the
242 // handler in this method. This handler might merely restore state
243 // (i.e. callee save registers) unwind the frame and jump to the
244 // exception handler for the nmethod if there is no Java level handler
245 // for the nmethod.
246 //
247 // This code is entered with a jmp.
248 //
249 // Arguments:
250 // rax: exception oop
251 // rdx: exception pc
252 //
253 // Results:
254 // rax: exception oop
255 // rdx: exception pc in caller or ???
256 // destination: exception handler of caller
257 //
258 // Note: the exception pc MUST be at a call (precise debug information)
259 // Registers rax, rdx, rcx, rsi, rdi, r8-r11 are not callee saved.
260 //
261
262 ExceptionBlob* OptoRuntime::generate_exception_blob() {
263 assert(!OptoRuntime::is_callee_saved_register(RDX_num), "");
264 assert(!OptoRuntime::is_callee_saved_register(RAX_num), "");
265 assert(!OptoRuntime::is_callee_saved_register(RCX_num), "");
266
267 assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
268
269 // Allocate space for the code
270 ResourceMark rm;
271 // Setup code generation tools
272 const char* name = OptoRuntime::stub_name(OptoStubId::exception_id);
273 CodeBuffer buffer(name, 2048, 1024);
274 if (buffer.blob() == nullptr) {
275 return nullptr;
276 }
277
278 int pc_offset = 0;
279 if (AOTCodeCache::load_exception_blob(&buffer, &pc_offset)) {
280 OopMapSet* oop_maps = new OopMapSet();
281 oop_maps->add_gc_map(pc_offset, new OopMap(SimpleRuntimeFrame::framesize, 0));
282
283 // Set exception blob
284 _exception_blob = ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
285 return _exception_blob;
286 }
287
288 MacroAssembler* masm = new MacroAssembler(&buffer);
289 address start = __ pc();
290
291 // Exception pc is 'return address' for stack walker
292 __ push(rdx);
293 __ subptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Prolog
294
295 // Save callee-saved registers. See x86_64.ad.
296
297 // rbp is an implicitly saved callee saved register (i.e., the calling
298 // convention will save/restore it in the prolog/epilog). Other than that
299 // there are no callee save registers now that adapter frames are gone.
300
301 __ movptr(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
302
303 // Store exception in Thread object. We cannot pass any arguments to the
304 // handle_exception call, since we do not want to make any assumption
305 // about the size of the frame where the exception happened in.
306 // c_rarg0 is either rdi (Linux) or rcx (Windows).
307 __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()),rax);
308 __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), rdx);
309
310 // This call does all the hard work. It checks if an exception handler
311 // exists in the method.
312 // If so, it returns the handler address.
313 // If not, it prepares for stack-unwinding, restoring the callee-save
314 // registers of the frame being removed.
315 //
316 // address OptoRuntime::handle_exception_C(JavaThread* thread)
317
318 // At a method handle call, the stack may not be properly aligned
319 // when returning with an exception.
320 address the_pc = __ pc();
321 __ set_last_Java_frame(noreg, noreg, the_pc, rscratch1);
322 __ mov(c_rarg0, r15_thread);
323 __ andptr(rsp, -(StackAlignmentInBytes)); // Align stack
324 __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
325
326 // Set an oopmap for the call site. This oopmap will only be used if we
327 // are unwinding the stack. Hence, all locations will be dead.
328 // Callee-saved registers will be the same as the frame above (i.e.,
329 // handle_exception_stub), since they were restored when we got the
330 // exception.
331
332 OopMapSet* oop_maps = new OopMapSet();
333
334 pc_offset = the_pc - start;
335 oop_maps->add_gc_map(pc_offset, new OopMap(SimpleRuntimeFrame::framesize, 0));
336
337 __ reset_last_Java_frame(false);
338
339 // Restore callee-saved registers
340
341 // rbp is an implicitly saved callee-saved register (i.e., the calling
342 // convention will save restore it in prolog/epilog) Other than that
343 // there are no callee save registers now that adapter frames are gone.
344
345 __ movptr(rbp, Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt));
346
347 __ addptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog
348 __ pop(rdx); // No need for exception pc anymore
349
350 // rax: exception handler
351
352 // We have a handler in rax (could be deopt blob).
353 __ mov(r8, rax);
354
355 // Get the exception oop
356 __ movptr(rax, Address(r15_thread, JavaThread::exception_oop_offset()));
357 // Get the exception pc in case we are deoptimized
358 __ movptr(rdx, Address(r15_thread, JavaThread::exception_pc_offset()));
359 #ifdef ASSERT
360 __ movptr(Address(r15_thread, JavaThread::exception_handler_pc_offset()), NULL_WORD);
361 __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), NULL_WORD);
362 #endif
363 // Clear the exception oop so GC no longer processes it as a root.
364 __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()), NULL_WORD);
365
366 // rax: exception oop
367 // r8: exception handler
368 // rdx: exception pc
369 // Jump to handler
370
371 __ jmp(r8);
372
373 // Make sure all code is generated
374 masm->flush();
375
376 AOTCodeCache::store_exception_blob(&buffer, pc_offset);
377 // Set exception blob
378 return ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
379 }
380 #endif // COMPILER2