Mercurial > hg > truffle
annotate src/share/vm/opto/callGenerator.hpp @ 1138:dd57230ba8fe
6893268: additional dynamic language related optimizations in C2
Summary: C2 needs some additional optimizations to be able to handle MethodHandle invokes and invokedynamic instructions at the best performance.
Reviewed-by: kvn, never
| author | twisti |
|---|---|
| date | Tue, 05 Jan 2010 15:21:25 +0100 |
| parents | 97125851f396 |
| children | c18cbe5936b8 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 * Copyright 2000-2005 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 //---------------------------CallGenerator------------------------------------- | |
| 26 // The subclasses of this class handle generation of ideal nodes for | |
| 27 // call sites and method entry points. | |
| 28 | |
| 29 class CallGenerator : public ResourceObj { | |
| 30 public: | |
| 31 enum { | |
| 32 xxxunusedxxx | |
| 33 }; | |
| 34 | |
| 35 private: | |
| 36 ciMethod* _method; // The method being called. | |
| 37 | |
| 38 protected: | |
| 39 CallGenerator(ciMethod* method); | |
| 40 | |
| 41 public: | |
| 42 // Accessors | |
| 43 ciMethod* method() const { return _method; } | |
| 44 | |
| 45 // is_inline: At least some code implementing the method is copied here. | |
| 46 virtual bool is_inline() const { return false; } | |
| 47 // is_intrinsic: There's a method-specific way of generating the inline code. | |
| 48 virtual bool is_intrinsic() const { return false; } | |
| 49 // is_parse: Bytecodes implementing the specific method are copied here. | |
| 50 virtual bool is_parse() const { return false; } | |
| 51 // is_virtual: The call uses the receiver type to select or check the method. | |
| 52 virtual bool is_virtual() const { return false; } | |
| 53 // is_deferred: The decision whether to inline or not is deferred. | |
| 54 virtual bool is_deferred() const { return false; } | |
| 55 // is_predicted: Uses an explicit check against a predicted type. | |
| 56 virtual bool is_predicted() const { return false; } | |
| 57 // is_trap: Does not return to the caller. (E.g., uncommon trap.) | |
| 58 virtual bool is_trap() const { return false; } | |
| 59 | |
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60 // is_late_inline: supports conversion of call into an inline |
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61 virtual bool is_late_inline() const { return false; } |
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62 // Replace the call with an inline version of the code |
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63 virtual void do_late_inline() { ShouldNotReachHere(); } |
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64 |
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65 virtual CallStaticJavaNode* call_node() const { ShouldNotReachHere(); return NULL; } |
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66 |
| 0 | 67 // Note: It is possible for a CG to be both inline and virtual. |
| 68 // (The hashCode intrinsic does a vtable check and an inlined fast path.) | |
| 69 | |
| 70 // Utilities: | |
| 71 const TypeFunc* tf() const; | |
| 72 | |
| 73 // The given jvms has state and arguments for a call to my method. | |
| 74 // Edges after jvms->argoff() carry all (pre-popped) argument values. | |
| 75 // | |
| 76 // Update the map with state and return values (if any) and return it. | |
| 77 // The return values (0, 1, or 2) must be pushed on the map's stack, | |
| 78 // and the sp of the jvms incremented accordingly. | |
| 79 // | |
| 80 // The jvms is returned on success. Alternatively, a copy of the | |
| 81 // given jvms, suitably updated, may be returned, in which case the | |
| 82 // caller should discard the original jvms. | |
| 83 // | |
| 84 // The non-Parm edges of the returned map will contain updated global state, | |
| 85 // and one or two edges before jvms->sp() will carry any return values. | |
| 86 // Other map edges may contain locals or monitors, and should not | |
| 87 // be changed in meaning. | |
| 88 // | |
| 89 // If the call traps, the returned map must have a control edge of top. | |
| 90 // If the call can throw, the returned map must report has_exceptions(). | |
| 91 // | |
| 92 // If the result is NULL, it means that this CallGenerator was unable | |
| 93 // to handle the given call, and another CallGenerator should be consulted. | |
| 94 virtual JVMState* generate(JVMState* jvms) = 0; | |
| 95 | |
| 96 // How to generate a call site that is inlined: | |
| 97 static CallGenerator* for_inline(ciMethod* m, float expected_uses = -1); | |
| 98 // How to generate code for an on-stack replacement handler. | |
| 99 static CallGenerator* for_osr(ciMethod* m, int osr_bci); | |
| 100 | |
| 101 // How to generate vanilla out-of-line call sites: | |
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102 static CallGenerator* for_direct_call(ciMethod* m, bool separate_io_projs = false); // static, special |
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103 static CallGenerator* for_dynamic_call(ciMethod* m); // invokedynamic |
| 0 | 104 static CallGenerator* for_virtual_call(ciMethod* m, int vtable_index); // virtual, interface |
| 105 | |
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106 // How to generate a replace a direct call with an inline version |
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107 static CallGenerator* for_late_inline(ciMethod* m, CallGenerator* inline_cg); |
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108 |
| 0 | 109 // How to make a call but defer the decision whether to inline or not. |
| 110 static CallGenerator* for_warm_call(WarmCallInfo* ci, | |
| 111 CallGenerator* if_cold, | |
| 112 CallGenerator* if_hot); | |
| 113 | |
| 114 // How to make a call that optimistically assumes a receiver type: | |
| 115 static CallGenerator* for_predicted_call(ciKlass* predicted_receiver, | |
| 116 CallGenerator* if_missed, | |
| 117 CallGenerator* if_hit, | |
| 118 float hit_prob); | |
| 119 | |
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120 // How to make a call that optimistically assumes a MethodHandle target: |
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121 static CallGenerator* for_predicted_dynamic_call(ciMethodHandle* predicted_method_handle, |
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122 CallGenerator* if_missed, |
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123 CallGenerator* if_hit, |
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124 float hit_prob); |
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125 |
| 0 | 126 // How to make a call that gives up and goes back to the interpreter: |
| 127 static CallGenerator* for_uncommon_trap(ciMethod* m, | |
| 128 Deoptimization::DeoptReason reason, | |
| 129 Deoptimization::DeoptAction action); | |
| 130 | |
| 131 // Registry for intrinsics: | |
| 132 static CallGenerator* for_intrinsic(ciMethod* m); | |
| 133 static void register_intrinsic(ciMethod* m, CallGenerator* cg); | |
| 134 }; | |
| 135 | |
| 136 class InlineCallGenerator : public CallGenerator { | |
| 137 virtual bool is_inline() const { return true; } | |
| 138 | |
| 139 protected: | |
| 140 InlineCallGenerator(ciMethod* method) : CallGenerator(method) { } | |
| 141 }; | |
| 142 | |
| 143 | |
| 144 //---------------------------WarmCallInfo-------------------------------------- | |
| 145 // A struct to collect information about a given call site. | |
| 146 // Helps sort call sites into "hot", "medium", and "cold". | |
| 147 // Participates in the queueing of "medium" call sites for possible inlining. | |
| 148 class WarmCallInfo : public ResourceObj { | |
| 149 private: | |
| 150 | |
| 151 CallNode* _call; // The CallNode which may be inlined. | |
| 152 CallGenerator* _hot_cg;// CG for expanding the call node | |
| 153 | |
| 154 // These are the metrics we use to evaluate call sites: | |
| 155 | |
| 156 float _count; // How often do we expect to reach this site? | |
| 157 float _profit; // How much time do we expect to save by inlining? | |
| 158 float _work; // How long do we expect the average call to take? | |
| 159 float _size; // How big do we expect the inlined code to be? | |
| 160 | |
| 161 float _heat; // Combined score inducing total order on call sites. | |
| 162 WarmCallInfo* _next; // Next cooler call info in pending queue. | |
| 163 | |
| 164 // Count is the number of times this call site is expected to be executed. | |
| 165 // Large count is favorable for inlining, because the extra compilation | |
| 166 // work will be amortized more completely. | |
| 167 | |
| 168 // Profit is a rough measure of the amount of time we expect to save | |
| 169 // per execution of this site if we inline it. (1.0 == call overhead) | |
| 170 // Large profit favors inlining. Negative profit disables inlining. | |
| 171 | |
| 172 // Work is a rough measure of the amount of time a typical out-of-line | |
| 173 // call from this site is expected to take. (1.0 == call, no-op, return) | |
| 174 // Small work is somewhat favorable for inlining, since methods with | |
| 175 // short "hot" traces are more likely to inline smoothly. | |
| 176 | |
| 177 // Size is the number of graph nodes we expect this method to produce, | |
| 178 // not counting the inlining of any further warm calls it may include. | |
| 179 // Small size favors inlining, since small methods are more likely to | |
| 180 // inline smoothly. The size is estimated by examining the native code | |
| 181 // if available. The method bytecodes are also examined, assuming | |
| 182 // empirically observed node counts for each kind of bytecode. | |
| 183 | |
| 184 // Heat is the combined "goodness" of a site's inlining. If we were | |
| 185 // omniscient, it would be the difference of two sums of future execution | |
| 186 // times of code emitted for this site (amortized across multiple sites if | |
| 187 // sharing applies). The two sums are for versions of this call site with | |
| 188 // and without inlining. | |
| 189 | |
| 190 // We approximate this mythical quantity by playing with averages, | |
| 191 // rough estimates, and assumptions that history repeats itself. | |
| 192 // The basic formula count * profit is heuristically adjusted | |
| 193 // by looking at the expected compilation and execution times of | |
| 194 // of the inlined call. | |
| 195 | |
| 196 // Note: Some of these metrics may not be present in the final product, | |
| 197 // but exist in development builds to experiment with inline policy tuning. | |
| 198 | |
| 199 // This heuristic framework does not model well the very significant | |
| 200 // effects of multiple-level inlining. It is possible to see no immediate | |
| 201 // profit from inlining X->Y, but to get great profit from a subsequent | |
| 202 // inlining X->Y->Z. | |
| 203 | |
| 204 // This framework does not take well into account the problem of N**2 code | |
| 205 // size in a clique of mutually inlinable methods. | |
| 206 | |
| 207 WarmCallInfo* next() const { return _next; } | |
| 208 void set_next(WarmCallInfo* n) { _next = n; } | |
| 209 | |
| 210 static WarmCallInfo* _always_hot; | |
| 211 static WarmCallInfo* _always_cold; | |
| 212 | |
| 213 public: | |
| 214 // Because WarmInfo objects live over the entire lifetime of the | |
| 215 // Compile object, they are allocated into the comp_arena, which | |
| 216 // does not get resource marked or reset during the compile process | |
| 217 void *operator new( size_t x, Compile* C ) { return C->comp_arena()->Amalloc(x); } | |
| 218 void operator delete( void * ) { } // fast deallocation | |
| 219 | |
| 220 static WarmCallInfo* always_hot(); | |
| 221 static WarmCallInfo* always_cold(); | |
| 222 | |
| 223 WarmCallInfo() { | |
| 224 _call = NULL; | |
| 225 _hot_cg = NULL; | |
| 226 _next = NULL; | |
| 227 _count = _profit = _work = _size = _heat = 0; | |
| 228 } | |
| 229 | |
| 230 CallNode* call() const { return _call; } | |
| 231 float count() const { return _count; } | |
| 232 float size() const { return _size; } | |
| 233 float work() const { return _work; } | |
| 234 float profit() const { return _profit; } | |
| 235 float heat() const { return _heat; } | |
| 236 | |
| 237 void set_count(float x) { _count = x; } | |
| 238 void set_size(float x) { _size = x; } | |
| 239 void set_work(float x) { _work = x; } | |
| 240 void set_profit(float x) { _profit = x; } | |
| 241 void set_heat(float x) { _heat = x; } | |
| 242 | |
| 243 // Load initial heuristics from profiles, etc. | |
| 244 // The heuristics can be tweaked further by the caller. | |
| 245 void init(JVMState* call_site, ciMethod* call_method, ciCallProfile& profile, float prof_factor); | |
| 246 | |
| 247 static float MAX_VALUE() { return +1.0e10; } | |
| 248 static float MIN_VALUE() { return -1.0e10; } | |
| 249 | |
| 250 float compute_heat() const; | |
| 251 | |
| 252 void set_call(CallNode* call) { _call = call; } | |
| 253 void set_hot_cg(CallGenerator* cg) { _hot_cg = cg; } | |
| 254 | |
| 255 // Do not queue very hot or very cold calls. | |
| 256 // Make very cold ones out of line immediately. | |
| 257 // Inline very hot ones immediately. | |
| 258 // These queries apply various tunable limits | |
| 259 // to the above metrics in a systematic way. | |
| 260 // Test for coldness before testing for hotness. | |
| 261 bool is_cold() const; | |
| 262 bool is_hot() const; | |
| 263 | |
| 264 // Force a warm call to be hot. This worklists the call node for inlining. | |
| 265 void make_hot(); | |
| 266 | |
| 267 // Force a warm call to be cold. This worklists the call node for out-of-lining. | |
| 268 void make_cold(); | |
| 269 | |
| 270 // A reproducible total ordering, in which heat is the major key. | |
| 271 bool warmer_than(WarmCallInfo* that); | |
| 272 | |
| 273 // List management. These methods are called with the list head, | |
| 274 // and return the new list head, inserting or removing the receiver. | |
| 275 WarmCallInfo* insert_into(WarmCallInfo* head); | |
| 276 WarmCallInfo* remove_from(WarmCallInfo* head); | |
| 277 | |
| 278 #ifndef PRODUCT | |
| 279 void print() const; | |
| 280 void print_all() const; | |
| 281 int count_all() const; | |
| 282 #endif | |
| 283 }; |