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