Mercurial > jdk8-mips64-public > hotspot / changeset

     1.1 --- a/src/share/vm/opto/loopTransform.cpp	Thu Apr 28 14:00:13 2011 -0700
     1.2 +++ b/src/share/vm/opto/loopTransform.cpp	Thu Apr 28 16:40:23 2011 -0700
     1.3 @@ -632,6 +632,8 @@
     1.4  }
     1.5  
     1.6  
     1.7 +#define MAX_UNROLL 16 // maximum number of unrolls for main loop
     1.8 +
     1.9  //------------------------------policy_unroll----------------------------------
    1.10  // Return TRUE or FALSE if the loop should be unrolled or not.  Unroll if
    1.11  // the loop is a CountedLoop and the body is small enough.
    1.12 @@ -646,10 +648,11 @@
    1.13    // protect against over-unrolling
    1.14    if (cl->trip_count() <= 1) return false;
    1.15  
    1.16 -  // Check for stride being a small enough constant
    1.17 -  if (abs(cl->stride_con()) > (1<<3)) return false;
    1.18 +  int future_unroll_ct = cl->unrolled_count() * 2;
    1.19 +  if (future_unroll_ct > MAX_UNROLL) return false;
    1.20  
    1.21 -  int future_unroll_ct = cl->unrolled_count() * 2;
    1.22 +  // Check for initial stride being a small enough constant
    1.23 +  if (abs(cl->stride_con()) > (1<<2)*future_unroll_ct) return false;
    1.24  
    1.25    // Don't unroll if the next round of unrolling would push us
    1.26    // over the expected trip count of the loop.  One is subtracted