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.
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23 */
24
25 #ifdef COMPILER2
26 #include "asm/macroAssembler.hpp"
27 #include "asm/macroAssembler.inline.hpp"
28 #include "code/vmreg.hpp"
29 #include "interpreter/interpreter.hpp"
30 #include "opto/runtime.hpp"
31 #include "runtime/sharedRuntime.hpp"
32 #include "runtime/stubRoutines.hpp"
33 #include "runtime/vframeArray.hpp"
34 #include "utilities/globalDefinitions.hpp"
35 #include "vmreg_x86.inline.hpp"
36
37 class SimpleRuntimeFrame {
38
39 public:
40
41 // Most of the runtime stubs have this simple frame layout.
42 // This class exists to make the layout shared in one place.
43 // Offsets are for compiler stack slots, which are jints.
44 enum layout {
45 // The frame sender code expects that rbp will be in the "natural" place and
46 // will override any oopMap setting for it. We must therefore force the layout
47 // so that it agrees with the frame sender code.
48 rbp_off = frame::arg_reg_save_area_bytes/BytesPerInt,
49 rbp_off2,
50 return_off, return_off2,
51 framesize
52 };
53 };
54
55 #define __ masm->
56
57 //------------------------------generate_uncommon_trap_blob--------------------
58 UncommonTrapBlob* OptoRuntime::generate_uncommon_trap_blob() {
59 // Allocate space for the code
60 ResourceMark rm;
61 // Setup code generation tools
62 const char* name = OptoRuntime::stub_name(OptoStubId::uncommon_trap_id);
63 CodeBuffer buffer(name, 2048, 1024);
64 if (buffer.blob() == nullptr) {
65 return nullptr;
66 }
67 MacroAssembler* masm = new MacroAssembler(&buffer);
68
69 assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
70
71 address start = __ pc();
72
73 // Push self-frame. We get here with a return address on the
74 // stack, so rsp is 8-byte aligned until we allocate our frame.
75 __ subptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog!
76
77 // No callee saved registers. rbp is assumed implicitly saved
78 __ movptr(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
79
80 // compiler left unloaded_class_index in j_rarg0 move to where the
81 // runtime expects it.
82 __ movl(c_rarg1, j_rarg0);
83
84 __ set_last_Java_frame(noreg, noreg, nullptr, rscratch1);
85
86 // Call C code. Need thread but NOT official VM entry
87 // crud. We cannot block on this call, no GC can happen. Call should
88 // capture callee-saved registers as well as return values.
89 // Thread is in rdi already.
90 //
91 // UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
92
93 __ mov(c_rarg0, r15_thread);
94 __ movl(c_rarg2, Deoptimization::Unpack_uncommon_trap);
95 __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::uncommon_trap)));
96
97 // Set an oopmap for the call site
98 OopMapSet* oop_maps = new OopMapSet();
99 OopMap* map = new OopMap(SimpleRuntimeFrame::framesize, 0);
100
101 // location of rbp is known implicitly by the frame sender code
102
103 oop_maps->add_gc_map(__ pc() - start, map);
104
105 __ reset_last_Java_frame(false);
106
107 // Load UnrollBlock* into rdi
108 __ mov(rdi, rax);
109
110 #ifdef ASSERT
111 { Label L;
112 __ cmpptr(Address(rdi, Deoptimization::UnrollBlock::unpack_kind_offset()),
113 Deoptimization::Unpack_uncommon_trap);
114 __ jcc(Assembler::equal, L);
115 __ stop("OptoRuntime::generate_uncommon_trap_blob: expected Unpack_uncommon_trap");
116 __ bind(L);
117 }
118 #endif
119
120 // Pop all the frames we must move/replace.
121 //
122 // Frame picture (youngest to oldest)
123 // 1: self-frame (no frame link)
124 // 2: deopting frame (no frame link)
125 // 3: caller of deopting frame (could be compiled/interpreted).
126
127 // Pop self-frame. We have no frame, and must rely only on rax and rsp.
128 __ addptr(rsp, (SimpleRuntimeFrame::framesize - 2) << LogBytesPerInt); // Epilog!
129
130 // Pop deoptimized frame (int)
131 __ movl(rcx, Address(rdi,
132 Deoptimization::UnrollBlock::
133 size_of_deoptimized_frame_offset()));
134 __ addptr(rsp, rcx);
135
136 // rsp should be pointing at the return address to the caller (3)
137
138 // Pick up the initial fp we should save
139 // restore rbp before stack bang because if stack overflow is thrown it needs to be pushed (and preserved)
140 __ movptr(rbp, Address(rdi, Deoptimization::UnrollBlock::initial_info_offset()));
141
142 #ifdef ASSERT
143 // Compilers generate code that bang the stack by as much as the
144 // interpreter would need. So this stack banging should never
145 // trigger a fault. Verify that it does not on non product builds.
146 __ movl(rbx, Address(rdi ,Deoptimization::UnrollBlock::total_frame_sizes_offset()));
147 __ bang_stack_size(rbx, rcx);
148 #endif
149
150 // Load address of array of frame pcs into rcx (address*)
151 __ movptr(rcx, Address(rdi, Deoptimization::UnrollBlock::frame_pcs_offset()));
152
153 // Trash the return pc
154 __ addptr(rsp, wordSize);
155
156 // Load address of array of frame sizes into rsi (intptr_t*)
157 __ movptr(rsi, Address(rdi, Deoptimization::UnrollBlock:: frame_sizes_offset()));
158
159 // Counter
160 __ movl(rdx, Address(rdi, Deoptimization::UnrollBlock:: number_of_frames_offset())); // (int)
161
162 // Now adjust the caller's stack to make up for the extra locals but
163 // record the original sp so that we can save it in the skeletal
164 // interpreter frame and the stack walking of interpreter_sender
165 // will get the unextended sp value and not the "real" sp value.
166
167 const Register sender_sp = r8;
168
169 __ mov(sender_sp, rsp);
170 __ movl(rbx, Address(rdi, Deoptimization::UnrollBlock:: caller_adjustment_offset())); // (int)
171 __ subptr(rsp, rbx);
172
173 // Push interpreter frames in a loop
174 Label loop;
175 __ bind(loop);
176 __ movptr(rbx, Address(rsi, 0)); // Load frame size
177 __ subptr(rbx, 2 * wordSize); // We'll push pc and rbp by hand
178 __ pushptr(Address(rcx, 0)); // Save return address
179 __ enter(); // Save old & set new rbp
180 __ subptr(rsp, rbx); // Prolog
181 __ movptr(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize),
182 sender_sp); // Make it walkable
183 // This value is corrected by layout_activation_impl
184 __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), NULL_WORD);
185 __ mov(sender_sp, rsp); // Pass sender_sp to next frame
186 __ addptr(rsi, wordSize); // Bump array pointer (sizes)
187 __ addptr(rcx, wordSize); // Bump array pointer (pcs)
188 __ decrementl(rdx); // Decrement counter
189 __ jcc(Assembler::notZero, loop);
190 __ pushptr(Address(rcx, 0)); // Save final return address
191
192 // Re-push self-frame
193 __ enter(); // Save old & set new rbp
194 __ subptr(rsp, (SimpleRuntimeFrame::framesize - 4) << LogBytesPerInt);
195 // Prolog
196
197 // Use rbp because the frames look interpreted now
198 // Save "the_pc" since it cannot easily be retrieved using the last_java_SP after we aligned SP.
199 // Don't need the precise return PC here, just precise enough to point into this code blob.
200 address the_pc = __ pc();
201 __ set_last_Java_frame(noreg, rbp, the_pc, rscratch1);
202
203 // Call C code. Need thread but NOT official VM entry
204 // crud. We cannot block on this call, no GC can happen. Call should
205 // restore return values to their stack-slots with the new SP.
206 // Thread is in rdi already.
207 //
208 // BasicType unpack_frames(JavaThread* thread, int exec_mode);
209
210 __ andptr(rsp, -(StackAlignmentInBytes)); // Align SP as required by ABI
211 __ mov(c_rarg0, r15_thread);
212 __ movl(c_rarg1, Deoptimization::Unpack_uncommon_trap);
213 __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
214
215 // Set an oopmap for the call site
216 // Use the same PC we used for the last java frame
217 oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
218
219 // Clear fp AND pc
220 __ reset_last_Java_frame(true);
221
222 // Pop self-frame.
223 __ leave(); // Epilog
224
225 // Jump to interpreter
226 __ ret(0);
227
228 // Make sure all code is generated
229 masm->flush();
230
231 return UncommonTrapBlob::create(&buffer, oop_maps,
232 SimpleRuntimeFrame::framesize >> 1);
233 }
234
235 //------------------------------generate_exception_blob---------------------------
236 // creates exception blob at the end
237 // Using exception blob, this code is jumped from a compiled method.
238 // (see emit_exception_handler in x86_64.ad file)
239 //
240 // Given an exception pc at a call we call into the runtime for the
241 // handler in this method. This handler might merely restore state
242 // (i.e. callee save registers) unwind the frame and jump to the
243 // exception handler for the nmethod if there is no Java level handler
244 // for the nmethod.
245 //
246 // This code is entered with a jmp.
247 //
248 // Arguments:
249 // rax: exception oop
250 // rdx: exception pc
251 //
252 // Results:
253 // rax: exception oop
254 // rdx: exception pc in caller or ???
255 // destination: exception handler of caller
256 //
257 // Note: the exception pc MUST be at a call (precise debug information)
258 // Registers rax, rdx, rcx, rsi, rdi, r8-r11 are not callee saved.
259 //
260
261 ExceptionBlob* OptoRuntime::generate_exception_blob() {
262 assert(!OptoRuntime::is_callee_saved_register(RDX_num), "");
263 assert(!OptoRuntime::is_callee_saved_register(RAX_num), "");
264 assert(!OptoRuntime::is_callee_saved_register(RCX_num), "");
265
266 assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
267
268 // Allocate space for the code
269 ResourceMark rm;
270 // Setup code generation tools
271 const char* name = OptoRuntime::stub_name(OptoStubId::exception_id);
272 CodeBuffer buffer(name, 2048, 1024);
273 if (buffer.blob() == nullptr) {
274 return nullptr;
275 }
276 MacroAssembler* masm = new MacroAssembler(&buffer);
277
278
279 address start = __ pc();
280
281 // Exception pc is 'return address' for stack walker
282 __ push(rdx);
283 __ subptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Prolog
284
285 // Save callee-saved registers. See x86_64.ad.
286
287 // rbp is an implicitly saved callee saved register (i.e., the calling
288 // convention will save/restore it in the prolog/epilog). Other than that
289 // there are no callee save registers now that adapter frames are gone.
290
291 __ movptr(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
292
293 // Store exception in Thread object. We cannot pass any arguments to the
294 // handle_exception call, since we do not want to make any assumption
295 // about the size of the frame where the exception happened in.
296 // c_rarg0 is either rdi (Linux) or rcx (Windows).
297 __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()),rax);
298 __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), rdx);
299
300 // This call does all the hard work. It checks if an exception handler
301 // exists in the method.
302 // If so, it returns the handler address.
303 // If not, it prepares for stack-unwinding, restoring the callee-save
304 // registers of the frame being removed.
305 //
306 // address OptoRuntime::handle_exception_C(JavaThread* thread)
307
308 // At a method handle call, the stack may not be properly aligned
309 // when returning with an exception.
310 address the_pc = __ pc();
311 __ set_last_Java_frame(noreg, noreg, the_pc, rscratch1);
312 __ mov(c_rarg0, r15_thread);
313 __ andptr(rsp, -(StackAlignmentInBytes)); // Align stack
314 __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
315
316 // Set an oopmap for the call site. This oopmap will only be used if we
317 // are unwinding the stack. Hence, all locations will be dead.
318 // Callee-saved registers will be the same as the frame above (i.e.,
319 // handle_exception_stub), since they were restored when we got the
320 // exception.
321
322 OopMapSet* oop_maps = new OopMapSet();
323
324 oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
325
326 __ reset_last_Java_frame(false);
327
328 // Restore callee-saved registers
329
330 // rbp is an implicitly saved callee-saved register (i.e., the calling
331 // convention will save restore it in prolog/epilog) Other than that
332 // there are no callee save registers now that adapter frames are gone.
333
334 __ movptr(rbp, Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt));
335
336 __ addptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog
337 __ pop(rdx); // No need for exception pc anymore
338
339 // rax: exception handler
340
341 // We have a handler in rax (could be deopt blob).
342 __ mov(r8, rax);
343
344 // Get the exception oop
345 __ movptr(rax, Address(r15_thread, JavaThread::exception_oop_offset()));
346 // Get the exception pc in case we are deoptimized
347 __ movptr(rdx, Address(r15_thread, JavaThread::exception_pc_offset()));
348 #ifdef ASSERT
349 __ movptr(Address(r15_thread, JavaThread::exception_handler_pc_offset()), NULL_WORD);
350 __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), NULL_WORD);
351 #endif
352 // Clear the exception oop so GC no longer processes it as a root.
353 __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()), NULL_WORD);
354
355 // rax: exception oop
356 // r8: exception handler
357 // rdx: exception pc
358 // Jump to handler
359
360 __ jmp(r8);
361
362 // Make sure all code is generated
363 masm->flush();
364
365 // Set exception blob
366 return ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
367 }
368 #endif // COMPILER2