Mercurial > jdk8-mips64-public > hotspot / file comparison
comparison: src/share/vm/opto/loopTransform.cpp
src/share/vm/opto/loopTransform.cpp
- changeset 2865
- ae93231c7a1f
- parent 2750
- 6c97c830fb6f
- child 2877
- bad7ecd0b6ed
equal
deleted
inserted
replaced
| 2815:01fd6090fdd8 | 2865:ae93231c7a1f |
|---|---|
| 630 | 630 |
| 631 return true; // Do maximally unroll | 631 return true; // Do maximally unroll |
| 632 } | 632 } |
| 633 | 633 |
| 634 | 634 |
| 635 #define MAX_UNROLL 16 // maximum number of unrolls for main loop | |
| 636 | |
| 635 //------------------------------policy_unroll---------------------------------- | 637 //------------------------------policy_unroll---------------------------------- |
| 636 // Return TRUE or FALSE if the loop should be unrolled or not. Unroll if | 638 // Return TRUE or FALSE if the loop should be unrolled or not. Unroll if |
| 637 // the loop is a CountedLoop and the body is small enough. | 639 // the loop is a CountedLoop and the body is small enough. |
| 638 bool IdealLoopTree::policy_unroll( PhaseIdealLoop *phase ) const { | 640 bool IdealLoopTree::policy_unroll( PhaseIdealLoop *phase ) const { |
| 639 | 641 |
| 644 return false; // Malformed counted loop | 646 return false; // Malformed counted loop |
| 645 | 647 |
| 646 // protect against over-unrolling | 648 // protect against over-unrolling |
| 647 if (cl->trip_count() <= 1) return false; | 649 if (cl->trip_count() <= 1) return false; |
| 648 | 650 |
| 649 // Check for stride being a small enough constant | |
| 650 if (abs(cl->stride_con()) > (1<<3)) return false; | |
| 651 | |
| 652 int future_unroll_ct = cl->unrolled_count() * 2; | 651 int future_unroll_ct = cl->unrolled_count() * 2; |
| 652 if (future_unroll_ct > MAX_UNROLL) return false; | |
| 653 | |
| 654 // Check for initial stride being a small enough constant | |
| 655 if (abs(cl->stride_con()) > (1<<2)*future_unroll_ct) return false; | |
| 653 | 656 |
| 654 // Don't unroll if the next round of unrolling would push us | 657 // Don't unroll if the next round of unrolling would push us |
| 655 // over the expected trip count of the loop. One is subtracted | 658 // over the expected trip count of the loop. One is subtracted |
| 656 // from the expected trip count because the pre-loop normally | 659 // from the expected trip count because the pre-loop normally |
| 657 // executes 1 iteration. | 660 // executes 1 iteration. |
