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src/hotspot/share/opto/parse2.cpp

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1281     prob = (0+PROB_MIN) / 2;
1282   else if( !not_taken )
1283     prob = (1+PROB_MAX) / 2;
1284   else {                         // Compute probability of true path
1285     prob = (float)taken / (float)(taken + not_taken);
1286     if (prob > PROB_MAX)  prob = PROB_MAX;
1287     if (prob < PROB_MIN)   prob = PROB_MIN;
1288   }
1289 
1290   assert((cnt > 0.0f) && (prob > 0.0f),
1291          "Bad frequency assignment in if cnt=%g prob=%g taken=%d not_taken=%d", cnt, prob, taken, not_taken);
1292 
1293   if (C->log() != nullptr) {
1294     const char* prob_str = nullptr;
1295     if (prob >= PROB_MAX)  prob_str = (prob == PROB_MAX) ? "max" : "always";
1296     if (prob <= PROB_MIN)  prob_str = (prob == PROB_MIN) ? "min" : "never";
1297     char prob_str_buf[30];
1298     if (prob_str == nullptr) {
1299       jio_snprintf(prob_str_buf, sizeof(prob_str_buf), "%20.2f", prob);
1300       prob_str = prob_str_buf;






1301     }
1302     C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d' cnt='%f' prob='%s'",
1303                    iter().get_dest(), taken, not_taken, cnt, prob_str);
1304   }
1305   return prob;
1306 }
1307 
1308 //-----------------------------branch_prediction-------------------------------
1309 float Parse::branch_prediction(float& cnt,
1310                                BoolTest::mask btest,
1311                                int target_bci,
1312                                Node* test) {
1313   float prob = dynamic_branch_prediction(cnt, btest, test);
1314   // If prob is unknown, switch to static prediction
1315   if (prob != PROB_UNKNOWN)  return prob;
1316 
1317   prob = PROB_FAIR;                   // Set default value
1318   if (btest == BoolTest::eq)          // Exactly equal test?
1319     prob = PROB_STATIC_INFREQUENT;    // Assume its relatively infrequent
1320   else if (btest == BoolTest::ne)

1281     prob = (0+PROB_MIN) / 2;
1282   else if( !not_taken )
1283     prob = (1+PROB_MAX) / 2;
1284   else {                         // Compute probability of true path
1285     prob = (float)taken / (float)(taken + not_taken);
1286     if (prob > PROB_MAX)  prob = PROB_MAX;
1287     if (prob < PROB_MIN)   prob = PROB_MIN;
1288   }
1289 
1290   assert((cnt > 0.0f) && (prob > 0.0f),
1291          "Bad frequency assignment in if cnt=%g prob=%g taken=%d not_taken=%d", cnt, prob, taken, not_taken);
1292 
1293   if (C->log() != nullptr) {
1294     const char* prob_str = nullptr;
1295     if (prob >= PROB_MAX)  prob_str = (prob == PROB_MAX) ? "max" : "always";
1296     if (prob <= PROB_MIN)  prob_str = (prob == PROB_MIN) ? "min" : "never";
1297     char prob_str_buf[30];
1298     if (prob_str == nullptr) {
1299       jio_snprintf(prob_str_buf, sizeof(prob_str_buf), "%20.2f", prob);
1300       prob_str = prob_str_buf;
1301       // The %20.2f adds many spaces to the string, to avoid some
1302       // picky overflow warning as noted in 8211929.  But, 20 is the
1303       // *minimum* width, not *maximum*, so it's not clear how this
1304       // helps prevent overflow.  Looks like we were forced to work
1305       // around a bug in gcc.  In any case, strip the blanks.
1306       while (*prob_str == ' ')  ++prob_str;
1307     }
1308     C->log()->elem("branch target_bci='%d' taken='%d' not_taken='%d' cnt='%f' prob='%s'",
1309                    iter().get_dest(), taken, not_taken, cnt, prob_str);
1310   }
1311   return prob;
1312 }
1313 
1314 //-----------------------------branch_prediction-------------------------------
1315 float Parse::branch_prediction(float& cnt,
1316                                BoolTest::mask btest,
1317                                int target_bci,
1318                                Node* test) {
1319   float prob = dynamic_branch_prediction(cnt, btest, test);
1320   // If prob is unknown, switch to static prediction
1321   if (prob != PROB_UNKNOWN)  return prob;
1322 
1323   prob = PROB_FAIR;                   // Set default value
1324   if (btest == BoolTest::eq)          // Exactly equal test?
1325     prob = PROB_STATIC_INFREQUENT;    // Assume its relatively infrequent
1326   else if (btest == BoolTest::ne)
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