callGenerator.hpp revision 3718:b9a9ed0f8eeb
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See the GNU General Public License 1295421Sdarrenr * version 2 for more details (a copy is included in the LICENSE file that 1395421Sdarrenr * accompanied this code). 14153877Sguido * 15153877Sguido * You should have received a copy of the GNU General Public License version 1695421Sdarrenr * 2 along with this work; if not, write to the Free Software Foundation, 1795421Sdarrenr * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 1895421Sdarrenr * 1995421Sdarrenr * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2095421Sdarrenr * or visit www.oracle.com if you need additional information or have any 2195421Sdarrenr * questions. 2295421Sdarrenr * 2395421Sdarrenr */ 2495421Sdarrenr 2595421Sdarrenr#ifndef SHARE_VM_OPTO_CALLGENERATOR_HPP 2695421Sdarrenr#define SHARE_VM_OPTO_CALLGENERATOR_HPP 27130887Sdarrenr 28145510Sdarrenr#include "compiler/compileBroker.hpp" 29145510Sdarrenr#include "opto/callnode.hpp" 30153877Sguido#include "opto/compile.hpp" 31172771Sdarrenr#include "opto/type.hpp" 32#include "runtime/deoptimization.hpp" 33 34//---------------------------CallGenerator------------------------------------- 35// The subclasses of this class handle generation of ideal nodes for 36// call sites and method entry points. 37 38class CallGenerator : public ResourceObj { 39 public: 40 enum { 41 xxxunusedxxx 42 }; 43 44 private: 45 ciMethod* _method; // The method being called. 46 47 protected: 48 CallGenerator(ciMethod* method) : _method(method) {} 49 50 public: 51 // Accessors 52 ciMethod* method() const { return _method; } 53 54 // is_inline: At least some code implementing the method is copied here. 55 virtual bool is_inline() const { return false; } 56 // is_intrinsic: There's a method-specific way of generating the inline code. 57 virtual bool is_intrinsic() const { return false; } 58 // is_parse: Bytecodes implementing the specific method are copied here. 59 virtual bool is_parse() const { return false; } 60 // is_virtual: The call uses the receiver type to select or check the method. 61 virtual bool is_virtual() const { return false; } 62 // is_deferred: The decision whether to inline or not is deferred. 63 virtual bool is_deferred() const { return false; } 64 // is_predicted: Uses an explicit check against a predicted type. 65 virtual bool is_predicted() const { return false; } 66 // is_trap: Does not return to the caller. (E.g., uncommon trap.) 67 virtual bool is_trap() const { return false; } 68 69 // is_late_inline: supports conversion of call into an inline 70 virtual bool is_late_inline() const { return false; } 71 // Replace the call with an inline version of the code 72 virtual void do_late_inline() { ShouldNotReachHere(); } 73 74 virtual CallStaticJavaNode* call_node() const { ShouldNotReachHere(); return NULL; } 75 76 // Note: It is possible for a CG to be both inline and virtual. 77 // (The hashCode intrinsic does a vtable check and an inlined fast path.) 78 79 // Utilities: 80 const TypeFunc* tf() const; 81 82 // The given jvms has state and arguments for a call to my method. 83 // Edges after jvms->argoff() carry all (pre-popped) argument values. 84 // 85 // Update the map with state and return values (if any) and return it. 86 // The return values (0, 1, or 2) must be pushed on the map's stack, 87 // and the sp of the jvms incremented accordingly. 88 // 89 // The jvms is returned on success. Alternatively, a copy of the 90 // given jvms, suitably updated, may be returned, in which case the 91 // caller should discard the original jvms. 92 // 93 // The non-Parm edges of the returned map will contain updated global state, 94 // and one or two edges before jvms->sp() will carry any return values. 95 // Other map edges may contain locals or monitors, and should not 96 // be changed in meaning. 97 // 98 // If the call traps, the returned map must have a control edge of top. 99 // If the call can throw, the returned map must report has_exceptions(). 100 // 101 // If the result is NULL, it means that this CallGenerator was unable 102 // to handle the given call, and another CallGenerator should be consulted. 103 virtual JVMState* generate(JVMState* jvms) = 0; 104 105 // How to generate a call site that is inlined: 106 static CallGenerator* for_inline(ciMethod* m, float expected_uses = -1); 107 // How to generate code for an on-stack replacement handler. 108 static CallGenerator* for_osr(ciMethod* m, int osr_bci); 109 110 // How to generate vanilla out-of-line call sites: 111 static CallGenerator* for_direct_call(ciMethod* m, bool separate_io_projs = false); // static, special 112 static CallGenerator* for_virtual_call(ciMethod* m, int vtable_index); // virtual, interface 113 static CallGenerator* for_dynamic_call(ciMethod* m); // invokedynamic 114 115 static CallGenerator* for_method_handle_call( JVMState* jvms, ciMethod* caller, ciMethod* callee); 116 static CallGenerator* for_method_handle_inline(JVMState* jvms, ciMethod* caller, ciMethod* callee); 117 118 // How to generate a replace a direct call with an inline version 119 static CallGenerator* for_late_inline(ciMethod* m, CallGenerator* inline_cg); 120 121 // How to make a call but defer the decision whether to inline or not. 122 static CallGenerator* for_warm_call(WarmCallInfo* ci, 123 CallGenerator* if_cold, 124 CallGenerator* if_hot); 125 126 // How to make a call that optimistically assumes a receiver type: 127 static CallGenerator* for_predicted_call(ciKlass* predicted_receiver, 128 CallGenerator* if_missed, 129 CallGenerator* if_hit, 130 float hit_prob); 131 132 // How to make a call that optimistically assumes a MethodHandle target: 133 static CallGenerator* for_predicted_dynamic_call(ciMethodHandle* predicted_method_handle, 134 CallGenerator* if_missed, 135 CallGenerator* if_hit, 136 float hit_prob); 137 138 // How to make a call that gives up and goes back to the interpreter: 139 static CallGenerator* for_uncommon_trap(ciMethod* m, 140 Deoptimization::DeoptReason reason, 141 Deoptimization::DeoptAction action); 142 143 // Registry for intrinsics: 144 static CallGenerator* for_intrinsic(ciMethod* m); 145 static void register_intrinsic(ciMethod* m, CallGenerator* cg); 146 147 static void print_inlining(ciMethod* callee, int inline_level, int bci, const char* msg) { 148 if (PrintInlining) 149 CompileTask::print_inlining(callee, inline_level, bci, msg); 150 } 151}; 152 153 154//------------------------InlineCallGenerator---------------------------------- 155class InlineCallGenerator : public CallGenerator { 156 protected: 157 InlineCallGenerator(ciMethod* method) : CallGenerator(method) {} 158 159 public: 160 virtual bool is_inline() const { return true; } 161}; 162 163 164//---------------------------WarmCallInfo-------------------------------------- 165// A struct to collect information about a given call site. 166// Helps sort call sites into "hot", "medium", and "cold". 167// Participates in the queueing of "medium" call sites for possible inlining. 168class WarmCallInfo : public ResourceObj { 169 private: 170 171 CallNode* _call; // The CallNode which may be inlined. 172 CallGenerator* _hot_cg;// CG for expanding the call node 173 174 // These are the metrics we use to evaluate call sites: 175 176 float _count; // How often do we expect to reach this site? 177 float _profit; // How much time do we expect to save by inlining? 178 float _work; // How long do we expect the average call to take? 179 float _size; // How big do we expect the inlined code to be? 180 181 float _heat; // Combined score inducing total order on call sites. 182 WarmCallInfo* _next; // Next cooler call info in pending queue. 183 184 // Count is the number of times this call site is expected to be executed. 185 // Large count is favorable for inlining, because the extra compilation 186 // work will be amortized more completely. 187 188 // Profit is a rough measure of the amount of time we expect to save 189 // per execution of this site if we inline it. (1.0 == call overhead) 190 // Large profit favors inlining. Negative profit disables inlining. 191 192 // Work is a rough measure of the amount of time a typical out-of-line 193 // call from this site is expected to take. (1.0 == call, no-op, return) 194 // Small work is somewhat favorable for inlining, since methods with 195 // short "hot" traces are more likely to inline smoothly. 196 197 // Size is the number of graph nodes we expect this method to produce, 198 // not counting the inlining of any further warm calls it may include. 199 // Small size favors inlining, since small methods are more likely to 200 // inline smoothly. The size is estimated by examining the native code 201 // if available. The method bytecodes are also examined, assuming 202 // empirically observed node counts for each kind of bytecode. 203 204 // Heat is the combined "goodness" of a site's inlining. If we were 205 // omniscient, it would be the difference of two sums of future execution 206 // times of code emitted for this site (amortized across multiple sites if 207 // sharing applies). The two sums are for versions of this call site with 208 // and without inlining. 209 210 // We approximate this mythical quantity by playing with averages, 211 // rough estimates, and assumptions that history repeats itself. 212 // The basic formula count * profit is heuristically adjusted 213 // by looking at the expected compilation and execution times of 214 // of the inlined call. 215 216 // Note: Some of these metrics may not be present in the final product, 217 // but exist in development builds to experiment with inline policy tuning. 218 219 // This heuristic framework does not model well the very significant 220 // effects of multiple-level inlining. It is possible to see no immediate 221 // profit from inlining X->Y, but to get great profit from a subsequent 222 // inlining X->Y->Z. 223 224 // This framework does not take well into account the problem of N**2 code 225 // size in a clique of mutually inlinable methods. 226 227 WarmCallInfo* next() const { return _next; } 228 void set_next(WarmCallInfo* n) { _next = n; } 229 230 static WarmCallInfo _always_hot; 231 static WarmCallInfo _always_cold; 232 233 // Constructor intitialization of always_hot and always_cold 234 WarmCallInfo(float c, float p, float w, float s) { 235 _call = NULL; 236 _hot_cg = NULL; 237 _next = NULL; 238 _count = c; 239 _profit = p; 240 _work = w; 241 _size = s; 242 _heat = 0; 243 } 244 245 public: 246 // Because WarmInfo objects live over the entire lifetime of the 247 // Compile object, they are allocated into the comp_arena, which 248 // does not get resource marked or reset during the compile process 249 void *operator new( size_t x, Compile* C ) { return C->comp_arena()->Amalloc(x); } 250 void operator delete( void * ) { } // fast deallocation 251 252 static WarmCallInfo* always_hot(); 253 static WarmCallInfo* always_cold(); 254 255 WarmCallInfo() { 256 _call = NULL; 257 _hot_cg = NULL; 258 _next = NULL; 259 _count = _profit = _work = _size = _heat = 0; 260 } 261 262 CallNode* call() const { return _call; } 263 float count() const { return _count; } 264 float size() const { return _size; } 265 float work() const { return _work; } 266 float profit() const { return _profit; } 267 float heat() const { return _heat; } 268 269 void set_count(float x) { _count = x; } 270 void set_size(float x) { _size = x; } 271 void set_work(float x) { _work = x; } 272 void set_profit(float x) { _profit = x; } 273 void set_heat(float x) { _heat = x; } 274 275 // Load initial heuristics from profiles, etc. 276 // The heuristics can be tweaked further by the caller. 277 void init(JVMState* call_site, ciMethod* call_method, ciCallProfile& profile, float prof_factor); 278 279 static float MAX_VALUE() { return +1.0e10; } 280 static float MIN_VALUE() { return -1.0e10; } 281 282 float compute_heat() const; 283 284 void set_call(CallNode* call) { _call = call; } 285 void set_hot_cg(CallGenerator* cg) { _hot_cg = cg; } 286 287 // Do not queue very hot or very cold calls. 288 // Make very cold ones out of line immediately. 289 // Inline very hot ones immediately. 290 // These queries apply various tunable limits 291 // to the above metrics in a systematic way. 292 // Test for coldness before testing for hotness. 293 bool is_cold() const; 294 bool is_hot() const; 295 296 // Force a warm call to be hot. This worklists the call node for inlining. 297 void make_hot(); 298 299 // Force a warm call to be cold. This worklists the call node for out-of-lining. 300 void make_cold(); 301 302 // A reproducible total ordering, in which heat is the major key. 303 bool warmer_than(WarmCallInfo* that); 304 305 // List management. These methods are called with the list head, 306 // and return the new list head, inserting or removing the receiver. 307 WarmCallInfo* insert_into(WarmCallInfo* head); 308 WarmCallInfo* remove_from(WarmCallInfo* head); 309 310#ifndef PRODUCT 311 void print() const; 312 void print_all() const; 313 int count_all() const; 314#endif 315}; 316 317#endif // SHARE_VM_OPTO_CALLGENERATOR_HPP 318