diff options
Diffstat (limited to 'openmp/runtime/src/kmp_dispatch.cpp')
| -rw-r--r-- | openmp/runtime/src/kmp_dispatch.cpp | 44 |
1 files changed, 26 insertions, 18 deletions
diff --git a/openmp/runtime/src/kmp_dispatch.cpp b/openmp/runtime/src/kmp_dispatch.cpp index 23d736a1b5a..9c3974a2f4b 100644 --- a/openmp/runtime/src/kmp_dispatch.cpp +++ b/openmp/runtime/src/kmp_dispatch.cpp @@ -757,24 +757,29 @@ __kmp_dispatch_init( ); } } - - tc = ( ub - lb + st ); - if ( st != 1 ) { - if ( st < 0 ) { - if ( lb < ub ) { - tc = 0; // zero-trip - } else { // lb >= ub - tc = (ST)tc / st; // convert to signed division - } - } else { // st > 0 - if ( ub < lb ) { - tc = 0; // zero-trip - } else { // lb >= ub - tc /= st; - } + // compute trip count + if ( st == 1 ) { // most common case + if ( ub >= lb ) { + tc = ub - lb + 1; + } else { // ub < lb + tc = 0; // zero-trip + } + } else if ( st < 0 ) { + if ( lb >= ub ) { + // AC: cast to unsigned is needed for loops like (i=2B; i>-2B; i-=1B), + // where the division needs to be unsigned regardless of the result type + tc = (UT)(lb - ub) / (-st) + 1; + } else { // lb < ub + tc = 0; // zero-trip + } + } else { // st > 0 + if ( ub >= lb ) { + // AC: cast to unsigned is needed for loops like (i=-2B; i<2B; i+=1B), + // where the division needs to be unsigned regardless of the result type + tc = (UT)(ub - lb) / st + 1; + } else { // ub < lb + tc = 0; // zero-trip } - } else if ( ub < lb ) { // st == 1 - tc = 0; // zero-trip } // Any half-decent optimizer will remove this test when the blocks are empty since the macros expand to nothing @@ -2255,8 +2260,11 @@ __kmp_dist_get_bounds( trip_count = *pupper - *plower + 1; } else if(incr == -1) { trip_count = *plower - *pupper + 1; + } else if ( incr > 0 ) { + // upper-lower can exceed the limit of signed type + trip_count = (UT)(*pupper - *plower) / incr + 1; } else { - trip_count = (ST)(*pupper - *plower) / incr + 1; // cast to signed to cover incr<0 case + trip_count = (UT)(*plower - *pupper) / ( -incr ) + 1; } if( trip_count <= nteams ) { |
