1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2012, 2014 SAP AG. 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 "precompiled.hpp"
27 #include "asm/assembler.inline.hpp"
28 #include "asm/macroAssembler.inline.hpp"
29 #include "compiler/disassembler.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "runtime/java.hpp"
32 #include "runtime/os.hpp"
33 #include "runtime/stubCodeGenerator.hpp"
34 #include "utilities/defaultStream.hpp"
35 #include "vm_version_ppc.hpp"
36
37 # include <sys/sysinfo.h>
38
39 int VM_Version::_features = VM_Version::unknown_m;
40 int VM_Version::_measured_cache_line_size = 128; // default value
41 const char* VM_Version::_features_str = "";
42 bool VM_Version::_is_determine_features_test_running = false;
43
44
45 #define MSG(flag) \
46 if (flag && !FLAG_IS_DEFAULT(flag)) \
47 jio_fprintf(defaultStream::error_stream(), \
48 "warning: -XX:+" #flag " requires -XX:+UseSIGTRAP\n" \
49 " -XX:+" #flag " will be disabled!\n");
50
51 void VM_Version::initialize() {
52
53 // Test which instructions are supported and measure cache line size.
54 determine_features();
55
56 // If PowerArchitecturePPC64 hasn't been specified explicitly determine from features.
57 if (FLAG_IS_DEFAULT(PowerArchitecturePPC64)) {
58 if (VM_Version::has_popcntw()) {
59 FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 7);
60 } else if (VM_Version::has_cmpb()) {
61 FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 6);
62 } else if (VM_Version::has_popcntb()) {
63 FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 5);
64 } else {
65 FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 0);
66 }
67 }
68 guarantee(PowerArchitecturePPC64 == 0 || PowerArchitecturePPC64 == 5 ||
69 PowerArchitecturePPC64 == 6 || PowerArchitecturePPC64 == 7,
70 "PowerArchitecturePPC64 should be 0, 5, 6 or 7");
71
72 if (!UseSIGTRAP) {
73 MSG(TrapBasedICMissChecks);
74 MSG(TrapBasedNotEntrantChecks);
75 MSG(TrapBasedNullChecks);
76 FLAG_SET_ERGO(bool, TrapBasedNotEntrantChecks, false);
77 FLAG_SET_ERGO(bool, TrapBasedNullChecks, false);
78 FLAG_SET_ERGO(bool, TrapBasedICMissChecks, false);
79 }
80
81 #ifdef COMPILER2
82 if (!UseSIGTRAP) {
83 MSG(TrapBasedRangeChecks);
84 FLAG_SET_ERGO(bool, TrapBasedRangeChecks, false);
85 }
86
87 // On Power6 test for section size.
88 if (PowerArchitecturePPC64 == 6) {
89 determine_section_size();
90 // TODO: PPC port } else {
91 // TODO: PPC port PdScheduling::power6SectorSize = 0x20;
92 }
93
94 MaxVectorSize = 8;
95 #endif
96
97 // Create and print feature-string.
98 char buf[(num_features+1) * 16]; // Max 16 chars per feature.
99 jio_snprintf(buf, sizeof(buf),
100 "ppc64%s%s%s%s%s%s%s%s",
101 (has_fsqrt() ? " fsqrt" : ""),
102 (has_isel() ? " isel" : ""),
103 (has_lxarxeh() ? " lxarxeh" : ""),
104 (has_cmpb() ? " cmpb" : ""),
105 //(has_mftgpr()? " mftgpr" : ""),
106 (has_popcntb() ? " popcntb" : ""),
107 (has_popcntw() ? " popcntw" : ""),
108 (has_fcfids() ? " fcfids" : ""),
109 (has_vand() ? " vand" : "")
110 // Make sure number of %s matches num_features!
111 );
112 _features_str = os::strdup(buf);
113 NOT_PRODUCT(if (Verbose) print_features(););
114
115 // PPC64 supports 8-byte compare-exchange operations (see
116 // Atomic::cmpxchg and StubGenerator::generate_atomic_cmpxchg_ptr)
117 // and 'atomic long memory ops' (see Unsafe_GetLongVolatile).
118 _supports_cx8 = true;
119
120 UseSSE = 0; // Only on x86 and x64
121
122 intx cache_line_size = _measured_cache_line_size;
123
124 if (FLAG_IS_DEFAULT(AllocatePrefetchStyle)) AllocatePrefetchStyle = 1;
125
126 if (AllocatePrefetchStyle == 4) {
127 AllocatePrefetchStepSize = cache_line_size; // Need exact value.
128 if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) AllocatePrefetchLines = 12; // Use larger blocks by default.
129 if (AllocatePrefetchDistance < 0) AllocatePrefetchDistance = 2*cache_line_size; // Default is not defined?
130 } else {
131 if (cache_line_size > AllocatePrefetchStepSize) AllocatePrefetchStepSize = cache_line_size;
132 if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) AllocatePrefetchLines = 3; // Optimistic value.
133 if (AllocatePrefetchDistance < 0) AllocatePrefetchDistance = 3*cache_line_size; // Default is not defined?
134 }
135
136 assert(AllocatePrefetchLines > 0, "invalid value");
137 if (AllocatePrefetchLines < 1) // Set valid value in product VM.
138 AllocatePrefetchLines = 1; // Conservative value.
139
140 if (AllocatePrefetchStyle == 3 && AllocatePrefetchDistance < cache_line_size)
141 AllocatePrefetchStyle = 1; // Fall back if inappropriate.
142
143 assert(AllocatePrefetchStyle >= 0, "AllocatePrefetchStyle should be positive");
144 }
145
146 void VM_Version::print_features() {
147 tty->print_cr("Version: %s cache_line_size = %d", cpu_features(), (int) get_cache_line_size());
148 }
149
150 #ifdef COMPILER2
151 // Determine section size on power6: If section size is 8 instructions,
152 // there should be a difference between the two testloops of ~15 %. If
153 // no difference is detected the section is assumed to be 32 instructions.
154 void VM_Version::determine_section_size() {
155
156 int unroll = 80;
157
158 const int code_size = (2* unroll * 32 + 100)*BytesPerInstWord;
159
160 // Allocate space for the code.
161 ResourceMark rm;
162 CodeBuffer cb("detect_section_size", code_size, 0);
163 MacroAssembler* a = new MacroAssembler(&cb);
164
165 uint32_t *code = (uint32_t *)a->pc();
166 // Emit code.
167 void (*test1)() = (void(*)())(void *)a->function_entry();
168
169 Label l1;
170
171 a->li(R4, 1);
172 a->sldi(R4, R4, 28);
173 a->b(l1);
174 a->align(CodeEntryAlignment);
175
176 a->bind(l1);
177
178 for (int i = 0; i < unroll; i++) {
179 // Schleife 1
180 // ------- sector 0 ------------
181 // ;; 0
182 a->nop(); // 1
183 a->fpnop0(); // 2
184 a->fpnop1(); // 3
185 a->addi(R4,R4, -1); // 4
186
187 // ;; 1
188 a->nop(); // 5
189 a->fmr(F6, F6); // 6
190 a->fmr(F7, F7); // 7
191 a->endgroup(); // 8
192 // ------- sector 8 ------------
193
194 // ;; 2
195 a->nop(); // 9
196 a->nop(); // 10
197 a->fmr(F8, F8); // 11
198 a->fmr(F9, F9); // 12
199
200 // ;; 3
201 a->nop(); // 13
202 a->fmr(F10, F10); // 14
203 a->fmr(F11, F11); // 15
204 a->endgroup(); // 16
205 // -------- sector 16 -------------
206
207 // ;; 4
208 a->nop(); // 17
209 a->nop(); // 18
210 a->fmr(F15, F15); // 19
211 a->fmr(F16, F16); // 20
212
213 // ;; 5
214 a->nop(); // 21
215 a->fmr(F17, F17); // 22
216 a->fmr(F18, F18); // 23
217 a->endgroup(); // 24
218 // ------- sector 24 ------------
219
220 // ;; 6
221 a->nop(); // 25
222 a->nop(); // 26
223 a->fmr(F19, F19); // 27
224 a->fmr(F20, F20); // 28
225
226 // ;; 7
227 a->nop(); // 29
228 a->fmr(F21, F21); // 30
229 a->fmr(F22, F22); // 31
230 a->brnop0(); // 32
231
232 // ------- sector 32 ------------
233 }
234
235 // ;; 8
236 a->cmpdi(CCR0, R4, unroll); // 33
237 a->bge(CCR0, l1); // 34
238 a->blr();
239
240 // Emit code.
241 void (*test2)() = (void(*)())(void *)a->function_entry();
242 // uint32_t *code = (uint32_t *)a->pc();
243
244 Label l2;
245
246 a->li(R4, 1);
247 a->sldi(R4, R4, 28);
248 a->b(l2);
249 a->align(CodeEntryAlignment);
250
251 a->bind(l2);
252
253 for (int i = 0; i < unroll; i++) {
254 // Schleife 2
255 // ------- sector 0 ------------
256 // ;; 0
257 a->brnop0(); // 1
258 a->nop(); // 2
259 //a->cmpdi(CCR0, R4, unroll);
260 a->fpnop0(); // 3
261 a->fpnop1(); // 4
262 a->addi(R4,R4, -1); // 5
263
264 // ;; 1
265
266 a->nop(); // 6
267 a->fmr(F6, F6); // 7
268 a->fmr(F7, F7); // 8
269 // ------- sector 8 ---------------
270
271 // ;; 2
272 a->endgroup(); // 9
273
274 // ;; 3
275 a->nop(); // 10
276 a->nop(); // 11
277 a->fmr(F8, F8); // 12
278
279 // ;; 4
280 a->fmr(F9, F9); // 13
281 a->nop(); // 14
282 a->fmr(F10, F10); // 15
283
284 // ;; 5
285 a->fmr(F11, F11); // 16
286 // -------- sector 16 -------------
287
288 // ;; 6
289 a->endgroup(); // 17
290
291 // ;; 7
292 a->nop(); // 18
293 a->nop(); // 19
294 a->fmr(F15, F15); // 20
295
296 // ;; 8
297 a->fmr(F16, F16); // 21
298 a->nop(); // 22
299 a->fmr(F17, F17); // 23
300
301 // ;; 9
302 a->fmr(F18, F18); // 24
303 // -------- sector 24 -------------
304
305 // ;; 10
306 a->endgroup(); // 25
307
308 // ;; 11
309 a->nop(); // 26
310 a->nop(); // 27
311 a->fmr(F19, F19); // 28
312
313 // ;; 12
314 a->fmr(F20, F20); // 29
315 a->nop(); // 30
316 a->fmr(F21, F21); // 31
317
318 // ;; 13
319 a->fmr(F22, F22); // 32
320 }
321
322 // -------- sector 32 -------------
323 // ;; 14
324 a->cmpdi(CCR0, R4, unroll); // 33
325 a->bge(CCR0, l2); // 34
326
327 a->blr();
328 uint32_t *code_end = (uint32_t *)a->pc();
329 a->flush();
330
331 double loop1_seconds,loop2_seconds, rel_diff;
332 uint64_t start1, stop1;
333
334 start1 = os::current_thread_cpu_time(false);
335 (*test1)();
336 stop1 = os::current_thread_cpu_time(false);
337 loop1_seconds = (stop1- start1) / (1000 *1000 *1000.0);
338
339
340 start1 = os::current_thread_cpu_time(false);
341 (*test2)();
342 stop1 = os::current_thread_cpu_time(false);
343
344 loop2_seconds = (stop1 - start1) / (1000 *1000 *1000.0);
345
346 rel_diff = (loop2_seconds - loop1_seconds) / loop1_seconds *100;
347
348 if (PrintAssembly) {
349 ttyLocker ttyl;
350 tty->print_cr("Decoding section size detection stub at " INTPTR_FORMAT " before execution:", p2i(code));
351 Disassembler::decode((u_char*)code, (u_char*)code_end, tty);
352 tty->print_cr("Time loop1 :%f", loop1_seconds);
353 tty->print_cr("Time loop2 :%f", loop2_seconds);
354 tty->print_cr("(time2 - time1) / time1 = %f %%", rel_diff);
355
356 if (rel_diff > 12.0) {
357 tty->print_cr("Section Size 8 Instructions");
358 } else{
359 tty->print_cr("Section Size 32 Instructions or Power5");
360 }
361 }
362
363 #if 0 // TODO: PPC port
364 // Set sector size (if not set explicitly).
365 if (FLAG_IS_DEFAULT(Power6SectorSize128PPC64)) {
366 if (rel_diff > 12.0) {
367 PdScheduling::power6SectorSize = 0x20;
368 } else {
369 PdScheduling::power6SectorSize = 0x80;
370 }
371 } else if (Power6SectorSize128PPC64) {
372 PdScheduling::power6SectorSize = 0x80;
373 } else {
374 PdScheduling::power6SectorSize = 0x20;
375 }
376 #endif
377 if (UsePower6SchedulerPPC64) Unimplemented();
378 }
379 #endif // COMPILER2
380
381 void VM_Version::determine_features() {
382 #if defined(ABI_ELFv2)
383 const int code_size = (num_features+1+2*7)*BytesPerInstWord; // TODO(asmundak): calculation is incorrect.
384 #else
385 // 7 InstWords for each call (function descriptor + blr instruction).
386 const int code_size = (num_features+1+2*7)*BytesPerInstWord;
387 #endif
388 int features = 0;
389
390 // create test area
391 enum { BUFFER_SIZE = 2*4*K }; // Needs to be >=2* max cache line size (cache line size can't exceed min page size).
392 char test_area[BUFFER_SIZE];
393 char *mid_of_test_area = &test_area[BUFFER_SIZE>>1];
394
395 // Allocate space for the code.
396 ResourceMark rm;
397 CodeBuffer cb("detect_cpu_features", code_size, 0);
398 MacroAssembler* a = new MacroAssembler(&cb);
399
400 // Must be set to true so we can generate the test code.
401 _features = VM_Version::all_features_m;
402
403 // Emit code.
404 void (*test)(address addr, uint64_t offset)=(void(*)(address addr, uint64_t offset))(void *)a->function_entry();
405 uint32_t *code = (uint32_t *)a->pc();
406 // Don't use R0 in ldarx.
407 // Keep R3_ARG1 unmodified, it contains &field (see below).
408 // Keep R4_ARG2 unmodified, it contains offset = 0 (see below).
409 a->fsqrt(F3, F4); // code[0] -> fsqrt_m
410 a->fsqrts(F3, F4); // code[1] -> fsqrts_m
411 a->isel(R7, R5, R6, 0); // code[2] -> isel_m
412 a->ldarx_unchecked(R7, R3_ARG1, R4_ARG2, 1); // code[3] -> lxarx_m
413 a->cmpb(R7, R5, R6); // code[4] -> bcmp
414 //a->mftgpr(R7, F3); // code[5] -> mftgpr
415 a->popcntb(R7, R5); // code[6] -> popcntb
416 a->popcntw(R7, R5); // code[7] -> popcntw
417 a->fcfids(F3, F4); // code[8] -> fcfids
418 a->vand(VR0, VR0, VR0); // code[9] -> vand
419 a->blr();
420
421 // Emit function to set one cache line to zero. Emit function descriptor and get pointer to it.
422 void (*zero_cacheline_func_ptr)(char*) = (void(*)(char*))(void *)a->function_entry();
423 a->dcbz(R3_ARG1); // R3_ARG1 = addr
424 a->blr();
425
426 uint32_t *code_end = (uint32_t *)a->pc();
427 a->flush();
428 _features = VM_Version::unknown_m;
429
430 // Print the detection code.
431 if (PrintAssembly) {
432 ttyLocker ttyl;
433 tty->print_cr("Decoding cpu-feature detection stub at " INTPTR_FORMAT " before execution:", p2i(code));
434 Disassembler::decode((u_char*)code, (u_char*)code_end, tty);
435 }
436
437 // Measure cache line size.
438 memset(test_area, 0xFF, BUFFER_SIZE); // Fill test area with 0xFF.
439 (*zero_cacheline_func_ptr)(mid_of_test_area); // Call function which executes dcbz to the middle.
440 int count = 0; // count zeroed bytes
441 for (int i = 0; i < BUFFER_SIZE; i++) if (test_area[i] == 0) count++;
442 guarantee(is_power_of_2(count), "cache line size needs to be a power of 2");
443 _measured_cache_line_size = count;
444
445 // Execute code. Illegal instructions will be replaced by 0 in the signal handler.
446 VM_Version::_is_determine_features_test_running = true;
447 (*test)((address)mid_of_test_area, (uint64_t)0);
448 VM_Version::_is_determine_features_test_running = false;
449
450 // determine which instructions are legal.
451 int feature_cntr = 0;
452 if (code[feature_cntr++]) features |= fsqrt_m;
453 if (code[feature_cntr++]) features |= fsqrts_m;
454 if (code[feature_cntr++]) features |= isel_m;
455 if (code[feature_cntr++]) features |= lxarxeh_m;
456 if (code[feature_cntr++]) features |= cmpb_m;
457 //if(code[feature_cntr++])features |= mftgpr_m;
458 if (code[feature_cntr++]) features |= popcntb_m;
459 if (code[feature_cntr++]) features |= popcntw_m;
460 if (code[feature_cntr++]) features |= fcfids_m;
461 if (code[feature_cntr++]) features |= vand_m;
462
463 // Print the detection code.
464 if (PrintAssembly) {
465 ttyLocker ttyl;
466 tty->print_cr("Decoding cpu-feature detection stub at " INTPTR_FORMAT " after execution:", p2i(code));
467 Disassembler::decode((u_char*)code, (u_char*)code_end, tty);
468 }
469
470 _features = features;
471 }
472
473
474 static int saved_features = 0;
475
476 void VM_Version::allow_all() {
477 saved_features = _features;
478 _features = all_features_m;
479 }
480
481 void VM_Version::revert() {
482 _features = saved_features;
483 }