Mercurial > hg > graal-jvmci-8
comparison src/cpu/sparc/vm/nativeInst_sparc.cpp @ 0:a61af66fc99e jdk7-b24
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author | duke |
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date | Sat, 01 Dec 2007 00:00:00 +0000 |
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children | 018d5b58dd4f |
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1 /* | |
2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
21 * have any questions. | |
22 * | |
23 */ | |
24 | |
25 # include "incls/_precompiled.incl" | |
26 # include "incls/_nativeInst_sparc.cpp.incl" | |
27 | |
28 | |
29 void NativeInstruction::set_data64_sethi(address instaddr, intptr_t x) { | |
30 ResourceMark rm; | |
31 CodeBuffer buf(instaddr, 10 * BytesPerInstWord ); | |
32 MacroAssembler* _masm = new MacroAssembler(&buf); | |
33 Register destreg; | |
34 | |
35 destreg = inv_rd(*(unsigned int *)instaddr); | |
36 // Generate a the new sequence | |
37 Address dest( destreg, (address)x ); | |
38 _masm->sethi( dest, true ); | |
39 ICache::invalidate_range(instaddr, 7 * BytesPerInstWord); | |
40 } | |
41 | |
42 void NativeInstruction::verify() { | |
43 // make sure code pattern is actually an instruction address | |
44 address addr = addr_at(0); | |
45 if (addr == 0 || ((intptr_t)addr & 3) != 0) { | |
46 fatal("not an instruction address"); | |
47 } | |
48 } | |
49 | |
50 void NativeInstruction::print() { | |
51 tty->print_cr(INTPTR_FORMAT ": 0x%x", addr_at(0), long_at(0)); | |
52 } | |
53 | |
54 void NativeInstruction::set_long_at(int offset, int i) { | |
55 address addr = addr_at(offset); | |
56 *(int*)addr = i; | |
57 ICache::invalidate_word(addr); | |
58 } | |
59 | |
60 void NativeInstruction::set_jlong_at(int offset, jlong i) { | |
61 address addr = addr_at(offset); | |
62 *(jlong*)addr = i; | |
63 // Don't need to invalidate 2 words here, because | |
64 // the flush instruction operates on doublewords. | |
65 ICache::invalidate_word(addr); | |
66 } | |
67 | |
68 void NativeInstruction::set_addr_at(int offset, address x) { | |
69 address addr = addr_at(offset); | |
70 assert( ((intptr_t)addr & (wordSize-1)) == 0, "set_addr_at bad address alignment"); | |
71 *(uintptr_t*)addr = (uintptr_t)x; | |
72 // Don't need to invalidate 2 words here in the 64-bit case, | |
73 // because the flush instruction operates on doublewords. | |
74 ICache::invalidate_word(addr); | |
75 // The Intel code has this assertion for NativeCall::set_destination, | |
76 // NativeMovConstReg::set_data, NativeMovRegMem::set_offset, | |
77 // NativeJump::set_jump_destination, and NativePushImm32::set_data | |
78 //assert (Patching_lock->owned_by_self(), "must hold lock to patch instruction") | |
79 } | |
80 | |
81 bool NativeInstruction::is_zero_test(Register ®) { | |
82 int x = long_at(0); | |
83 Assembler::op3s temp = (Assembler::op3s) (Assembler::sub_op3 | Assembler::cc_bit_op3); | |
84 if (is_op3(x, temp, Assembler::arith_op) && | |
85 inv_immed(x) && inv_rd(x) == G0) { | |
86 if (inv_rs1(x) == G0) { | |
87 reg = inv_rs2(x); | |
88 return true; | |
89 } else if (inv_rs2(x) == G0) { | |
90 reg = inv_rs1(x); | |
91 return true; | |
92 } | |
93 } | |
94 return false; | |
95 } | |
96 | |
97 bool NativeInstruction::is_load_store_with_small_offset(Register reg) { | |
98 int x = long_at(0); | |
99 if (is_op(x, Assembler::ldst_op) && | |
100 inv_rs1(x) == reg && inv_immed(x)) { | |
101 return true; | |
102 } | |
103 return false; | |
104 } | |
105 | |
106 void NativeCall::verify() { | |
107 NativeInstruction::verify(); | |
108 // make sure code pattern is actually a call instruction | |
109 if (!is_op(long_at(0), Assembler::call_op)) { | |
110 fatal("not a call"); | |
111 } | |
112 } | |
113 | |
114 void NativeCall::print() { | |
115 tty->print_cr(INTPTR_FORMAT ": call " INTPTR_FORMAT, instruction_address(), destination()); | |
116 } | |
117 | |
118 | |
119 // MT-safe patching of a call instruction (and following word). | |
120 // First patches the second word, and then atomicly replaces | |
121 // the first word with the first new instruction word. | |
122 // Other processors might briefly see the old first word | |
123 // followed by the new second word. This is OK if the old | |
124 // second word is harmless, and the new second word may be | |
125 // harmlessly executed in the delay slot of the call. | |
126 void NativeCall::replace_mt_safe(address instr_addr, address code_buffer) { | |
127 assert(Patching_lock->is_locked() || | |
128 SafepointSynchronize::is_at_safepoint(), "concurrent code patching"); | |
129 assert (instr_addr != NULL, "illegal address for code patching"); | |
130 NativeCall* n_call = nativeCall_at (instr_addr); // checking that it is a call | |
131 assert(NativeCall::instruction_size == 8, "wrong instruction size; must be 8"); | |
132 int i0 = ((int*)code_buffer)[0]; | |
133 int i1 = ((int*)code_buffer)[1]; | |
134 int* contention_addr = (int*) n_call->addr_at(1*BytesPerInstWord); | |
135 assert(inv_op(*contention_addr) == Assembler::arith_op || | |
136 *contention_addr == nop_instruction() || !VM_Version::v9_instructions_work(), | |
137 "must not interfere with original call"); | |
138 // The set_long_at calls do the ICacheInvalidate so we just need to do them in reverse order | |
139 n_call->set_long_at(1*BytesPerInstWord, i1); | |
140 n_call->set_long_at(0*BytesPerInstWord, i0); | |
141 // NOTE: It is possible that another thread T will execute | |
142 // only the second patched word. | |
143 // In other words, since the original instruction is this | |
144 // call patching_stub; nop (NativeCall) | |
145 // and the new sequence from the buffer is this: | |
146 // sethi %hi(K), %r; add %r, %lo(K), %r (NativeMovConstReg) | |
147 // what T will execute is this: | |
148 // call patching_stub; add %r, %lo(K), %r | |
149 // thereby putting garbage into %r before calling the patching stub. | |
150 // This is OK, because the patching stub ignores the value of %r. | |
151 | |
152 // Make sure the first-patched instruction, which may co-exist | |
153 // briefly with the call, will do something harmless. | |
154 assert(inv_op(*contention_addr) == Assembler::arith_op || | |
155 *contention_addr == nop_instruction() || !VM_Version::v9_instructions_work(), | |
156 "must not interfere with original call"); | |
157 } | |
158 | |
159 // Similar to replace_mt_safe, but just changes the destination. The | |
160 // important thing is that free-running threads are able to execute this | |
161 // call instruction at all times. Thus, the displacement field must be | |
162 // instruction-word-aligned. This is always true on SPARC. | |
163 // | |
164 // Used in the runtime linkage of calls; see class CompiledIC. | |
165 void NativeCall::set_destination_mt_safe(address dest) { | |
166 assert(Patching_lock->is_locked() || | |
167 SafepointSynchronize::is_at_safepoint(), "concurrent code patching"); | |
168 // set_destination uses set_long_at which does the ICache::invalidate | |
169 set_destination(dest); | |
170 } | |
171 | |
172 // Code for unit testing implementation of NativeCall class | |
173 void NativeCall::test() { | |
174 #ifdef ASSERT | |
175 ResourceMark rm; | |
176 CodeBuffer cb("test", 100, 100); | |
177 MacroAssembler* a = new MacroAssembler(&cb); | |
178 NativeCall *nc; | |
179 uint idx; | |
180 int offsets[] = { | |
181 0x0, | |
182 0xfffffff0, | |
183 0x7ffffff0, | |
184 0x80000000, | |
185 0x20, | |
186 0x4000, | |
187 }; | |
188 | |
189 VM_Version::allow_all(); | |
190 | |
191 a->call( a->pc(), relocInfo::none ); | |
192 a->delayed()->nop(); | |
193 nc = nativeCall_at( cb.code_begin() ); | |
194 nc->print(); | |
195 | |
196 nc = nativeCall_overwriting_at( nc->next_instruction_address() ); | |
197 for (idx = 0; idx < ARRAY_SIZE(offsets); idx++) { | |
198 nc->set_destination( cb.code_begin() + offsets[idx] ); | |
199 assert(nc->destination() == (cb.code_begin() + offsets[idx]), "check unit test"); | |
200 nc->print(); | |
201 } | |
202 | |
203 nc = nativeCall_before( cb.code_begin() + 8 ); | |
204 nc->print(); | |
205 | |
206 VM_Version::revert(); | |
207 #endif | |
208 } | |
209 // End code for unit testing implementation of NativeCall class | |
210 | |
211 //------------------------------------------------------------------- | |
212 | |
213 #ifdef _LP64 | |
214 | |
215 void NativeFarCall::set_destination(address dest) { | |
216 // Address materialized in the instruction stream, so nothing to do. | |
217 return; | |
218 #if 0 // What we'd do if we really did want to change the destination | |
219 if (destination() == dest) { | |
220 return; | |
221 } | |
222 ResourceMark rm; | |
223 CodeBuffer buf(addr_at(0), instruction_size + 1); | |
224 MacroAssembler* _masm = new MacroAssembler(&buf); | |
225 // Generate the new sequence | |
226 Address(O7, dest); | |
227 _masm->jumpl_to(dest, O7); | |
228 ICache::invalidate_range(addr_at(0), instruction_size ); | |
229 #endif | |
230 } | |
231 | |
232 void NativeFarCall::verify() { | |
233 // make sure code pattern is actually a jumpl_to instruction | |
234 assert((int)instruction_size == (int)NativeJump::instruction_size, "same as jump_to"); | |
235 assert((int)jmpl_offset == (int)NativeMovConstReg::add_offset, "sethi size ok"); | |
236 nativeJump_at(addr_at(0))->verify(); | |
237 } | |
238 | |
239 bool NativeFarCall::is_call_at(address instr) { | |
240 return nativeInstruction_at(instr)->is_sethi(); | |
241 } | |
242 | |
243 void NativeFarCall::print() { | |
244 tty->print_cr(INTPTR_FORMAT ": call " INTPTR_FORMAT, instruction_address(), destination()); | |
245 } | |
246 | |
247 bool NativeFarCall::destination_is_compiled_verified_entry_point() { | |
248 nmethod* callee = CodeCache::find_nmethod(destination()); | |
249 if (callee == NULL) { | |
250 return false; | |
251 } else { | |
252 return destination() == callee->verified_entry_point(); | |
253 } | |
254 } | |
255 | |
256 // MT-safe patching of a far call. | |
257 void NativeFarCall::replace_mt_safe(address instr_addr, address code_buffer) { | |
258 Unimplemented(); | |
259 } | |
260 | |
261 // Code for unit testing implementation of NativeFarCall class | |
262 void NativeFarCall::test() { | |
263 Unimplemented(); | |
264 } | |
265 // End code for unit testing implementation of NativeFarCall class | |
266 | |
267 #endif // _LP64 | |
268 | |
269 //------------------------------------------------------------------- | |
270 | |
271 | |
272 void NativeMovConstReg::verify() { | |
273 NativeInstruction::verify(); | |
274 // make sure code pattern is actually a "set_oop" synthetic instruction | |
275 // see MacroAssembler::set_oop() | |
276 int i0 = long_at(sethi_offset); | |
277 int i1 = long_at(add_offset); | |
278 | |
279 // verify the pattern "sethi %hi22(imm), reg ; add reg, %lo10(imm), reg" | |
280 Register rd = inv_rd(i0); | |
281 #ifndef _LP64 | |
282 if (!(is_op2(i0, Assembler::sethi_op2) && rd != G0 && | |
283 is_op3(i1, Assembler::add_op3, Assembler::arith_op) && | |
284 inv_immed(i1) && (unsigned)get_simm13(i1) < (1 << 10) && | |
285 rd == inv_rs1(i1) && rd == inv_rd(i1))) { | |
286 fatal("not a set_oop"); | |
287 } | |
288 #else | |
289 if (!is_op2(i0, Assembler::sethi_op2) && rd != G0 ) { | |
290 fatal("not a set_oop"); | |
291 } | |
292 #endif | |
293 } | |
294 | |
295 | |
296 void NativeMovConstReg::print() { | |
297 tty->print_cr(INTPTR_FORMAT ": mov reg, " INTPTR_FORMAT, instruction_address(), data()); | |
298 } | |
299 | |
300 | |
301 #ifdef _LP64 | |
302 intptr_t NativeMovConstReg::data() const { | |
303 return data64(addr_at(sethi_offset), long_at(add_offset)); | |
304 } | |
305 #else | |
306 intptr_t NativeMovConstReg::data() const { | |
307 return data32(long_at(sethi_offset), long_at(add_offset)); | |
308 } | |
309 #endif | |
310 | |
311 | |
312 void NativeMovConstReg::set_data(intptr_t x) { | |
313 #ifdef _LP64 | |
314 set_data64_sethi(addr_at(sethi_offset), x); | |
315 #else | |
316 set_long_at(sethi_offset, set_data32_sethi( long_at(sethi_offset), x)); | |
317 #endif | |
318 set_long_at(add_offset, set_data32_simm13( long_at(add_offset), x)); | |
319 | |
320 // also store the value into an oop_Relocation cell, if any | |
321 CodeBlob* nm = CodeCache::find_blob(instruction_address()); | |
322 if (nm != NULL) { | |
323 RelocIterator iter(nm, instruction_address(), next_instruction_address()); | |
324 oop* oop_addr = NULL; | |
325 while (iter.next()) { | |
326 if (iter.type() == relocInfo::oop_type) { | |
327 oop_Relocation *r = iter.oop_reloc(); | |
328 if (oop_addr == NULL) { | |
329 oop_addr = r->oop_addr(); | |
330 *oop_addr = (oop)x; | |
331 } else { | |
332 assert(oop_addr == r->oop_addr(), "must be only one set-oop here"); | |
333 } | |
334 } | |
335 } | |
336 } | |
337 } | |
338 | |
339 | |
340 // Code for unit testing implementation of NativeMovConstReg class | |
341 void NativeMovConstReg::test() { | |
342 #ifdef ASSERT | |
343 ResourceMark rm; | |
344 CodeBuffer cb("test", 100, 100); | |
345 MacroAssembler* a = new MacroAssembler(&cb); | |
346 NativeMovConstReg* nm; | |
347 uint idx; | |
348 int offsets[] = { | |
349 0x0, | |
350 0x7fffffff, | |
351 0x80000000, | |
352 0xffffffff, | |
353 0x20, | |
354 4096, | |
355 4097, | |
356 }; | |
357 | |
358 VM_Version::allow_all(); | |
359 | |
360 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); | |
361 a->add(I3, low10(0xaaaabbbb), I3); | |
362 a->sethi(0xccccdddd, O2, true, RelocationHolder::none); | |
363 a->add(O2, low10(0xccccdddd), O2); | |
364 | |
365 nm = nativeMovConstReg_at( cb.code_begin() ); | |
366 nm->print(); | |
367 | |
368 nm = nativeMovConstReg_at( nm->next_instruction_address() ); | |
369 for (idx = 0; idx < ARRAY_SIZE(offsets); idx++) { | |
370 nm->set_data( offsets[idx] ); | |
371 assert(nm->data() == offsets[idx], "check unit test"); | |
372 } | |
373 nm->print(); | |
374 | |
375 VM_Version::revert(); | |
376 #endif | |
377 } | |
378 // End code for unit testing implementation of NativeMovConstReg class | |
379 | |
380 //------------------------------------------------------------------- | |
381 | |
382 void NativeMovConstRegPatching::verify() { | |
383 NativeInstruction::verify(); | |
384 // Make sure code pattern is sethi/nop/add. | |
385 int i0 = long_at(sethi_offset); | |
386 int i1 = long_at(nop_offset); | |
387 int i2 = long_at(add_offset); | |
388 assert((int)nop_offset == (int)NativeMovConstReg::add_offset, "sethi size ok"); | |
389 | |
390 // Verify the pattern "sethi %hi22(imm), reg; nop; add reg, %lo10(imm), reg" | |
391 // The casual reader should note that on Sparc a nop is a special case if sethi | |
392 // in which the destination register is %g0. | |
393 Register rd0 = inv_rd(i0); | |
394 Register rd1 = inv_rd(i1); | |
395 if (!(is_op2(i0, Assembler::sethi_op2) && rd0 != G0 && | |
396 is_op2(i1, Assembler::sethi_op2) && rd1 == G0 && // nop is a special case of sethi | |
397 is_op3(i2, Assembler::add_op3, Assembler::arith_op) && | |
398 inv_immed(i2) && (unsigned)get_simm13(i2) < (1 << 10) && | |
399 rd0 == inv_rs1(i2) && rd0 == inv_rd(i2))) { | |
400 fatal("not a set_oop"); | |
401 } | |
402 } | |
403 | |
404 | |
405 void NativeMovConstRegPatching::print() { | |
406 tty->print_cr(INTPTR_FORMAT ": mov reg, " INTPTR_FORMAT, instruction_address(), data()); | |
407 } | |
408 | |
409 | |
410 int NativeMovConstRegPatching::data() const { | |
411 #ifdef _LP64 | |
412 return data64(addr_at(sethi_offset), long_at(add_offset)); | |
413 #else | |
414 return data32(long_at(sethi_offset), long_at(add_offset)); | |
415 #endif | |
416 } | |
417 | |
418 | |
419 void NativeMovConstRegPatching::set_data(int x) { | |
420 #ifdef _LP64 | |
421 set_data64_sethi(addr_at(sethi_offset), x); | |
422 #else | |
423 set_long_at(sethi_offset, set_data32_sethi(long_at(sethi_offset), x)); | |
424 #endif | |
425 set_long_at(add_offset, set_data32_simm13(long_at(add_offset), x)); | |
426 | |
427 // also store the value into an oop_Relocation cell, if any | |
428 CodeBlob* nm = CodeCache::find_blob(instruction_address()); | |
429 if (nm != NULL) { | |
430 RelocIterator iter(nm, instruction_address(), next_instruction_address()); | |
431 oop* oop_addr = NULL; | |
432 while (iter.next()) { | |
433 if (iter.type() == relocInfo::oop_type) { | |
434 oop_Relocation *r = iter.oop_reloc(); | |
435 if (oop_addr == NULL) { | |
436 oop_addr = r->oop_addr(); | |
437 *oop_addr = (oop)x; | |
438 } else { | |
439 assert(oop_addr == r->oop_addr(), "must be only one set-oop here"); | |
440 } | |
441 } | |
442 } | |
443 } | |
444 } | |
445 | |
446 | |
447 // Code for unit testing implementation of NativeMovConstRegPatching class | |
448 void NativeMovConstRegPatching::test() { | |
449 #ifdef ASSERT | |
450 ResourceMark rm; | |
451 CodeBuffer cb("test", 100, 100); | |
452 MacroAssembler* a = new MacroAssembler(&cb); | |
453 NativeMovConstRegPatching* nm; | |
454 uint idx; | |
455 int offsets[] = { | |
456 0x0, | |
457 0x7fffffff, | |
458 0x80000000, | |
459 0xffffffff, | |
460 0x20, | |
461 4096, | |
462 4097, | |
463 }; | |
464 | |
465 VM_Version::allow_all(); | |
466 | |
467 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); | |
468 a->nop(); | |
469 a->add(I3, low10(0xaaaabbbb), I3); | |
470 a->sethi(0xccccdddd, O2, true, RelocationHolder::none); | |
471 a->nop(); | |
472 a->add(O2, low10(0xccccdddd), O2); | |
473 | |
474 nm = nativeMovConstRegPatching_at( cb.code_begin() ); | |
475 nm->print(); | |
476 | |
477 nm = nativeMovConstRegPatching_at( nm->next_instruction_address() ); | |
478 for (idx = 0; idx < ARRAY_SIZE(offsets); idx++) { | |
479 nm->set_data( offsets[idx] ); | |
480 assert(nm->data() == offsets[idx], "check unit test"); | |
481 } | |
482 nm->print(); | |
483 | |
484 VM_Version::revert(); | |
485 #endif // ASSERT | |
486 } | |
487 // End code for unit testing implementation of NativeMovConstRegPatching class | |
488 | |
489 | |
490 //------------------------------------------------------------------- | |
491 | |
492 | |
493 void NativeMovRegMem::copy_instruction_to(address new_instruction_address) { | |
494 Untested("copy_instruction_to"); | |
495 int instruction_size = next_instruction_address() - instruction_address(); | |
496 for (int i = 0; i < instruction_size; i += BytesPerInstWord) { | |
497 *(int*)(new_instruction_address + i) = *(int*)(address(this) + i); | |
498 } | |
499 } | |
500 | |
501 | |
502 void NativeMovRegMem::verify() { | |
503 NativeInstruction::verify(); | |
504 // make sure code pattern is actually a "ld" or "st" of some sort. | |
505 int i0 = long_at(0); | |
506 int op3 = inv_op3(i0); | |
507 | |
508 assert((int)add_offset == NativeMovConstReg::add_offset, "sethi size ok"); | |
509 | |
510 if (!(is_op(i0, Assembler::ldst_op) && | |
511 inv_immed(i0) && | |
512 0 != (op3 < op3_ldst_int_limit | |
513 ? (1 << op3 ) & (op3_mask_ld | op3_mask_st) | |
514 : (1 << (op3 - op3_ldst_int_limit)) & (op3_mask_ldf | op3_mask_stf)))) | |
515 { | |
516 int i1 = long_at(ldst_offset); | |
517 Register rd = inv_rd(i0); | |
518 | |
519 op3 = inv_op3(i1); | |
520 if (!is_op(i1, Assembler::ldst_op) && rd == inv_rs2(i1) && | |
521 0 != (op3 < op3_ldst_int_limit | |
522 ? (1 << op3 ) & (op3_mask_ld | op3_mask_st) | |
523 : (1 << (op3 - op3_ldst_int_limit)) & (op3_mask_ldf | op3_mask_stf))) { | |
524 fatal("not a ld* or st* op"); | |
525 } | |
526 } | |
527 } | |
528 | |
529 | |
530 void NativeMovRegMem::print() { | |
531 if (is_immediate()) { | |
532 tty->print_cr(INTPTR_FORMAT ": mov reg, [reg + %x]", instruction_address(), offset()); | |
533 } else { | |
534 tty->print_cr(INTPTR_FORMAT ": mov reg, [reg + reg]", instruction_address()); | |
535 } | |
536 } | |
537 | |
538 | |
539 // Code for unit testing implementation of NativeMovRegMem class | |
540 void NativeMovRegMem::test() { | |
541 #ifdef ASSERT | |
542 ResourceMark rm; | |
543 CodeBuffer cb("test", 1000, 1000); | |
544 MacroAssembler* a = new MacroAssembler(&cb); | |
545 NativeMovRegMem* nm; | |
546 uint idx = 0; | |
547 uint idx1; | |
548 int offsets[] = { | |
549 0x0, | |
550 0xffffffff, | |
551 0x7fffffff, | |
552 0x80000000, | |
553 4096, | |
554 4097, | |
555 0x20, | |
556 0x4000, | |
557 }; | |
558 | |
559 VM_Version::allow_all(); | |
560 | |
561 a->ldsw( G5, low10(0xffffffff), G4 ); idx++; | |
562 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
563 a->ldsw( G5, I3, G4 ); idx++; | |
564 a->ldsb( G5, low10(0xffffffff), G4 ); idx++; | |
565 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
566 a->ldsb( G5, I3, G4 ); idx++; | |
567 a->ldsh( G5, low10(0xffffffff), G4 ); idx++; | |
568 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
569 a->ldsh( G5, I3, G4 ); idx++; | |
570 a->lduw( G5, low10(0xffffffff), G4 ); idx++; | |
571 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
572 a->lduw( G5, I3, G4 ); idx++; | |
573 a->ldub( G5, low10(0xffffffff), G4 ); idx++; | |
574 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
575 a->ldub( G5, I3, G4 ); idx++; | |
576 a->lduh( G5, low10(0xffffffff), G4 ); idx++; | |
577 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
578 a->lduh( G5, I3, G4 ); idx++; | |
579 a->ldx( G5, low10(0xffffffff), G4 ); idx++; | |
580 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
581 a->ldx( G5, I3, G4 ); idx++; | |
582 a->ldd( G5, low10(0xffffffff), G4 ); idx++; | |
583 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
584 a->ldd( G5, I3, G4 ); idx++; | |
585 a->ldf( FloatRegisterImpl::D, O2, -1, F14 ); idx++; | |
586 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
587 a->ldf( FloatRegisterImpl::S, O0, I3, F15 ); idx++; | |
588 | |
589 a->stw( G5, G4, low10(0xffffffff) ); idx++; | |
590 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
591 a->stw( G5, G4, I3 ); idx++; | |
592 a->stb( G5, G4, low10(0xffffffff) ); idx++; | |
593 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
594 a->stb( G5, G4, I3 ); idx++; | |
595 a->sth( G5, G4, low10(0xffffffff) ); idx++; | |
596 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
597 a->sth( G5, G4, I3 ); idx++; | |
598 a->stx( G5, G4, low10(0xffffffff) ); idx++; | |
599 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
600 a->stx( G5, G4, I3 ); idx++; | |
601 a->std( G5, G4, low10(0xffffffff) ); idx++; | |
602 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
603 a->std( G5, G4, I3 ); idx++; | |
604 a->stf( FloatRegisterImpl::S, F18, O2, -1 ); idx++; | |
605 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->add(I3, low10(0xaaaabbbb), I3); | |
606 a->stf( FloatRegisterImpl::S, F15, O0, I3 ); idx++; | |
607 | |
608 nm = nativeMovRegMem_at( cb.code_begin() ); | |
609 nm->print(); | |
610 nm->set_offset( low10(0) ); | |
611 nm->print(); | |
612 nm->add_offset_in_bytes( low10(0xbb) * wordSize ); | |
613 nm->print(); | |
614 | |
615 while (--idx) { | |
616 nm = nativeMovRegMem_at( nm->next_instruction_address() ); | |
617 nm->print(); | |
618 for (idx1 = 0; idx1 < ARRAY_SIZE(offsets); idx1++) { | |
619 nm->set_offset( nm->is_immediate() ? low10(offsets[idx1]) : offsets[idx1] ); | |
620 assert(nm->offset() == (nm->is_immediate() ? low10(offsets[idx1]) : offsets[idx1]), | |
621 "check unit test"); | |
622 nm->print(); | |
623 } | |
624 nm->add_offset_in_bytes( low10(0xbb) * wordSize ); | |
625 nm->print(); | |
626 } | |
627 | |
628 VM_Version::revert(); | |
629 #endif // ASSERT | |
630 } | |
631 | |
632 // End code for unit testing implementation of NativeMovRegMem class | |
633 | |
634 //-------------------------------------------------------------------------------- | |
635 | |
636 | |
637 void NativeMovRegMemPatching::copy_instruction_to(address new_instruction_address) { | |
638 Untested("copy_instruction_to"); | |
639 int instruction_size = next_instruction_address() - instruction_address(); | |
640 for (int i = 0; i < instruction_size; i += wordSize) { | |
641 *(long*)(new_instruction_address + i) = *(long*)(address(this) + i); | |
642 } | |
643 } | |
644 | |
645 | |
646 void NativeMovRegMemPatching::verify() { | |
647 NativeInstruction::verify(); | |
648 // make sure code pattern is actually a "ld" or "st" of some sort. | |
649 int i0 = long_at(0); | |
650 int op3 = inv_op3(i0); | |
651 | |
652 assert((int)nop_offset == (int)NativeMovConstReg::add_offset, "sethi size ok"); | |
653 | |
654 if (!(is_op(i0, Assembler::ldst_op) && | |
655 inv_immed(i0) && | |
656 0 != (op3 < op3_ldst_int_limit | |
657 ? (1 << op3 ) & (op3_mask_ld | op3_mask_st) | |
658 : (1 << (op3 - op3_ldst_int_limit)) & (op3_mask_ldf | op3_mask_stf)))) { | |
659 int i1 = long_at(ldst_offset); | |
660 Register rd = inv_rd(i0); | |
661 | |
662 op3 = inv_op3(i1); | |
663 if (!is_op(i1, Assembler::ldst_op) && rd == inv_rs2(i1) && | |
664 0 != (op3 < op3_ldst_int_limit | |
665 ? (1 << op3 ) & (op3_mask_ld | op3_mask_st) | |
666 : (1 << (op3 - op3_ldst_int_limit)) & (op3_mask_ldf | op3_mask_stf))) { | |
667 fatal("not a ld* or st* op"); | |
668 } | |
669 } | |
670 } | |
671 | |
672 | |
673 void NativeMovRegMemPatching::print() { | |
674 if (is_immediate()) { | |
675 tty->print_cr(INTPTR_FORMAT ": mov reg, [reg + %x]", instruction_address(), offset()); | |
676 } else { | |
677 tty->print_cr(INTPTR_FORMAT ": mov reg, [reg + reg]", instruction_address()); | |
678 } | |
679 } | |
680 | |
681 | |
682 // Code for unit testing implementation of NativeMovRegMemPatching class | |
683 void NativeMovRegMemPatching::test() { | |
684 #ifdef ASSERT | |
685 ResourceMark rm; | |
686 CodeBuffer cb("test", 1000, 1000); | |
687 MacroAssembler* a = new MacroAssembler(&cb); | |
688 NativeMovRegMemPatching* nm; | |
689 uint idx = 0; | |
690 uint idx1; | |
691 int offsets[] = { | |
692 0x0, | |
693 0xffffffff, | |
694 0x7fffffff, | |
695 0x80000000, | |
696 4096, | |
697 4097, | |
698 0x20, | |
699 0x4000, | |
700 }; | |
701 | |
702 VM_Version::allow_all(); | |
703 | |
704 a->ldsw( G5, low10(0xffffffff), G4 ); idx++; | |
705 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
706 a->ldsw( G5, I3, G4 ); idx++; | |
707 a->ldsb( G5, low10(0xffffffff), G4 ); idx++; | |
708 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
709 a->ldsb( G5, I3, G4 ); idx++; | |
710 a->ldsh( G5, low10(0xffffffff), G4 ); idx++; | |
711 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
712 a->ldsh( G5, I3, G4 ); idx++; | |
713 a->lduw( G5, low10(0xffffffff), G4 ); idx++; | |
714 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
715 a->lduw( G5, I3, G4 ); idx++; | |
716 a->ldub( G5, low10(0xffffffff), G4 ); idx++; | |
717 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
718 a->ldub( G5, I3, G4 ); idx++; | |
719 a->lduh( G5, low10(0xffffffff), G4 ); idx++; | |
720 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
721 a->lduh( G5, I3, G4 ); idx++; | |
722 a->ldx( G5, low10(0xffffffff), G4 ); idx++; | |
723 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
724 a->ldx( G5, I3, G4 ); idx++; | |
725 a->ldd( G5, low10(0xffffffff), G4 ); idx++; | |
726 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
727 a->ldd( G5, I3, G4 ); idx++; | |
728 a->ldf( FloatRegisterImpl::D, O2, -1, F14 ); idx++; | |
729 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
730 a->ldf( FloatRegisterImpl::S, O0, I3, F15 ); idx++; | |
731 | |
732 a->stw( G5, G4, low10(0xffffffff) ); idx++; | |
733 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
734 a->stw( G5, G4, I3 ); idx++; | |
735 a->stb( G5, G4, low10(0xffffffff) ); idx++; | |
736 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
737 a->stb( G5, G4, I3 ); idx++; | |
738 a->sth( G5, G4, low10(0xffffffff) ); idx++; | |
739 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
740 a->sth( G5, G4, I3 ); idx++; | |
741 a->stx( G5, G4, low10(0xffffffff) ); idx++; | |
742 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
743 a->stx( G5, G4, I3 ); idx++; | |
744 a->std( G5, G4, low10(0xffffffff) ); idx++; | |
745 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
746 a->std( G5, G4, I3 ); idx++; | |
747 a->stf( FloatRegisterImpl::S, F18, O2, -1 ); idx++; | |
748 a->sethi(0xaaaabbbb, I3, true, RelocationHolder::none); a->nop(); a->add(I3, low10(0xaaaabbbb), I3); | |
749 a->stf( FloatRegisterImpl::S, F15, O0, I3 ); idx++; | |
750 | |
751 nm = nativeMovRegMemPatching_at( cb.code_begin() ); | |
752 nm->print(); | |
753 nm->set_offset( low10(0) ); | |
754 nm->print(); | |
755 nm->add_offset_in_bytes( low10(0xbb) * wordSize ); | |
756 nm->print(); | |
757 | |
758 while (--idx) { | |
759 nm = nativeMovRegMemPatching_at( nm->next_instruction_address() ); | |
760 nm->print(); | |
761 for (idx1 = 0; idx1 < ARRAY_SIZE(offsets); idx1++) { | |
762 nm->set_offset( nm->is_immediate() ? low10(offsets[idx1]) : offsets[idx1] ); | |
763 assert(nm->offset() == (nm->is_immediate() ? low10(offsets[idx1]) : offsets[idx1]), | |
764 "check unit test"); | |
765 nm->print(); | |
766 } | |
767 nm->add_offset_in_bytes( low10(0xbb) * wordSize ); | |
768 nm->print(); | |
769 } | |
770 | |
771 VM_Version::revert(); | |
772 #endif // ASSERT | |
773 } | |
774 // End code for unit testing implementation of NativeMovRegMemPatching class | |
775 | |
776 | |
777 //-------------------------------------------------------------------------------- | |
778 | |
779 | |
780 void NativeJump::verify() { | |
781 NativeInstruction::verify(); | |
782 int i0 = long_at(sethi_offset); | |
783 int i1 = long_at(jmpl_offset); | |
784 assert((int)jmpl_offset == (int)NativeMovConstReg::add_offset, "sethi size ok"); | |
785 // verify the pattern "sethi %hi22(imm), treg ; jmpl treg, %lo10(imm), lreg" | |
786 Register rd = inv_rd(i0); | |
787 #ifndef _LP64 | |
788 if (!(is_op2(i0, Assembler::sethi_op2) && rd != G0 && | |
789 (is_op3(i1, Assembler::jmpl_op3, Assembler::arith_op) || | |
790 (TraceJumps && is_op3(i1, Assembler::add_op3, Assembler::arith_op))) && | |
791 inv_immed(i1) && (unsigned)get_simm13(i1) < (1 << 10) && | |
792 rd == inv_rs1(i1))) { | |
793 fatal("not a jump_to instruction"); | |
794 } | |
795 #else | |
796 // In LP64, the jump instruction location varies for non relocatable | |
797 // jumps, for example is could be sethi, xor, jmp instead of the | |
798 // 7 instructions for sethi. So let's check sethi only. | |
799 if (!is_op2(i0, Assembler::sethi_op2) && rd != G0 ) { | |
800 fatal("not a jump_to instruction"); | |
801 } | |
802 #endif | |
803 } | |
804 | |
805 | |
806 void NativeJump::print() { | |
807 tty->print_cr(INTPTR_FORMAT ": jmpl reg, " INTPTR_FORMAT, instruction_address(), jump_destination()); | |
808 } | |
809 | |
810 | |
811 // Code for unit testing implementation of NativeJump class | |
812 void NativeJump::test() { | |
813 #ifdef ASSERT | |
814 ResourceMark rm; | |
815 CodeBuffer cb("test", 100, 100); | |
816 MacroAssembler* a = new MacroAssembler(&cb); | |
817 NativeJump* nj; | |
818 uint idx; | |
819 int offsets[] = { | |
820 0x0, | |
821 0xffffffff, | |
822 0x7fffffff, | |
823 0x80000000, | |
824 4096, | |
825 4097, | |
826 0x20, | |
827 0x4000, | |
828 }; | |
829 | |
830 VM_Version::allow_all(); | |
831 | |
832 a->sethi(0x7fffbbbb, I3, true, RelocationHolder::none); | |
833 a->jmpl(I3, low10(0x7fffbbbb), G0, RelocationHolder::none); | |
834 a->delayed()->nop(); | |
835 a->sethi(0x7fffbbbb, I3, true, RelocationHolder::none); | |
836 a->jmpl(I3, low10(0x7fffbbbb), L3, RelocationHolder::none); | |
837 a->delayed()->nop(); | |
838 | |
839 nj = nativeJump_at( cb.code_begin() ); | |
840 nj->print(); | |
841 | |
842 nj = nativeJump_at( nj->next_instruction_address() ); | |
843 for (idx = 0; idx < ARRAY_SIZE(offsets); idx++) { | |
844 nj->set_jump_destination( nj->instruction_address() + offsets[idx] ); | |
845 assert(nj->jump_destination() == (nj->instruction_address() + offsets[idx]), "check unit test"); | |
846 nj->print(); | |
847 } | |
848 | |
849 VM_Version::revert(); | |
850 #endif // ASSERT | |
851 } | |
852 // End code for unit testing implementation of NativeJump class | |
853 | |
854 | |
855 void NativeJump::insert(address code_pos, address entry) { | |
856 Unimplemented(); | |
857 } | |
858 | |
859 // MT safe inserting of a jump over an unknown instruction sequence (used by nmethod::makeZombie) | |
860 // The problem: jump_to <dest> is a 3-word instruction (including its delay slot). | |
861 // Atomic write can be only with 1 word. | |
862 void NativeJump::patch_verified_entry(address entry, address verified_entry, address dest) { | |
863 // Here's one way to do it: Pre-allocate a three-word jump sequence somewhere | |
864 // in the header of the nmethod, within a short branch's span of the patch point. | |
865 // Set up the jump sequence using NativeJump::insert, and then use an annulled | |
866 // unconditional branch at the target site (an atomic 1-word update). | |
867 // Limitations: You can only patch nmethods, with any given nmethod patched at | |
868 // most once, and the patch must be in the nmethod's header. | |
869 // It's messy, but you can ask the CodeCache for the nmethod containing the | |
870 // target address. | |
871 | |
872 // %%%%% For now, do something MT-stupid: | |
873 ResourceMark rm; | |
874 int code_size = 1 * BytesPerInstWord; | |
875 CodeBuffer cb(verified_entry, code_size + 1); | |
876 MacroAssembler* a = new MacroAssembler(&cb); | |
877 if (VM_Version::v9_instructions_work()) { | |
878 a->ldsw(G0, 0, O7); // "ld" must agree with code in the signal handler | |
879 } else { | |
880 a->lduw(G0, 0, O7); // "ld" must agree with code in the signal handler | |
881 } | |
882 ICache::invalidate_range(verified_entry, code_size); | |
883 } | |
884 | |
885 | |
886 void NativeIllegalInstruction::insert(address code_pos) { | |
887 NativeIllegalInstruction* nii = (NativeIllegalInstruction*) nativeInstruction_at(code_pos); | |
888 nii->set_long_at(0, illegal_instruction()); | |
889 } | |
890 | |
891 static int illegal_instruction_bits = 0; | |
892 | |
893 int NativeInstruction::illegal_instruction() { | |
894 if (illegal_instruction_bits == 0) { | |
895 ResourceMark rm; | |
896 char buf[40]; | |
897 CodeBuffer cbuf((address)&buf[0], 20); | |
898 MacroAssembler* a = new MacroAssembler(&cbuf); | |
899 address ia = a->pc(); | |
900 a->trap(ST_RESERVED_FOR_USER_0 + 1); | |
901 int bits = *(int*)ia; | |
902 assert(is_op3(bits, Assembler::trap_op3, Assembler::arith_op), "bad instruction"); | |
903 illegal_instruction_bits = bits; | |
904 assert(illegal_instruction_bits != 0, "oops"); | |
905 } | |
906 return illegal_instruction_bits; | |
907 } | |
908 | |
909 static int ic_miss_trap_bits = 0; | |
910 | |
911 bool NativeInstruction::is_ic_miss_trap() { | |
912 if (ic_miss_trap_bits == 0) { | |
913 ResourceMark rm; | |
914 char buf[40]; | |
915 CodeBuffer cbuf((address)&buf[0], 20); | |
916 MacroAssembler* a = new MacroAssembler(&cbuf); | |
917 address ia = a->pc(); | |
918 a->trap(Assembler::notEqual, Assembler::ptr_cc, G0, ST_RESERVED_FOR_USER_0 + 2); | |
919 int bits = *(int*)ia; | |
920 assert(is_op3(bits, Assembler::trap_op3, Assembler::arith_op), "bad instruction"); | |
921 ic_miss_trap_bits = bits; | |
922 assert(ic_miss_trap_bits != 0, "oops"); | |
923 } | |
924 return long_at(0) == ic_miss_trap_bits; | |
925 } | |
926 | |
927 | |
928 bool NativeInstruction::is_illegal() { | |
929 if (illegal_instruction_bits == 0) { | |
930 return false; | |
931 } | |
932 return long_at(0) == illegal_instruction_bits; | |
933 } | |
934 | |
935 | |
936 void NativeGeneralJump::verify() { | |
937 assert(((NativeInstruction *)this)->is_jump() || | |
938 ((NativeInstruction *)this)->is_cond_jump(), "not a general jump instruction"); | |
939 } | |
940 | |
941 | |
942 void NativeGeneralJump::insert_unconditional(address code_pos, address entry) { | |
943 Assembler::Condition condition = Assembler::always; | |
944 int x = Assembler::op2(Assembler::br_op2) | Assembler::annul(false) | | |
945 Assembler::cond(condition) | Assembler::wdisp((intptr_t)entry, (intptr_t)code_pos, 22); | |
946 NativeGeneralJump* ni = (NativeGeneralJump*) nativeInstruction_at(code_pos); | |
947 ni->set_long_at(0, x); | |
948 } | |
949 | |
950 | |
951 // MT-safe patching of a jmp instruction (and following word). | |
952 // First patches the second word, and then atomicly replaces | |
953 // the first word with the first new instruction word. | |
954 // Other processors might briefly see the old first word | |
955 // followed by the new second word. This is OK if the old | |
956 // second word is harmless, and the new second word may be | |
957 // harmlessly executed in the delay slot of the call. | |
958 void NativeGeneralJump::replace_mt_safe(address instr_addr, address code_buffer) { | |
959 assert(Patching_lock->is_locked() || | |
960 SafepointSynchronize::is_at_safepoint(), "concurrent code patching"); | |
961 assert (instr_addr != NULL, "illegal address for code patching"); | |
962 NativeGeneralJump* h_jump = nativeGeneralJump_at (instr_addr); // checking that it is a call | |
963 assert(NativeGeneralJump::instruction_size == 8, "wrong instruction size; must be 8"); | |
964 int i0 = ((int*)code_buffer)[0]; | |
965 int i1 = ((int*)code_buffer)[1]; | |
966 int* contention_addr = (int*) h_jump->addr_at(1*BytesPerInstWord); | |
967 assert(inv_op(*contention_addr) == Assembler::arith_op || | |
968 *contention_addr == nop_instruction() || !VM_Version::v9_instructions_work(), | |
969 "must not interfere with original call"); | |
970 // The set_long_at calls do the ICacheInvalidate so we just need to do them in reverse order | |
971 h_jump->set_long_at(1*BytesPerInstWord, i1); | |
972 h_jump->set_long_at(0*BytesPerInstWord, i0); | |
973 // NOTE: It is possible that another thread T will execute | |
974 // only the second patched word. | |
975 // In other words, since the original instruction is this | |
976 // jmp patching_stub; nop (NativeGeneralJump) | |
977 // and the new sequence from the buffer is this: | |
978 // sethi %hi(K), %r; add %r, %lo(K), %r (NativeMovConstReg) | |
979 // what T will execute is this: | |
980 // jmp patching_stub; add %r, %lo(K), %r | |
981 // thereby putting garbage into %r before calling the patching stub. | |
982 // This is OK, because the patching stub ignores the value of %r. | |
983 | |
984 // Make sure the first-patched instruction, which may co-exist | |
985 // briefly with the call, will do something harmless. | |
986 assert(inv_op(*contention_addr) == Assembler::arith_op || | |
987 *contention_addr == nop_instruction() || !VM_Version::v9_instructions_work(), | |
988 "must not interfere with original call"); | |
989 } |