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52 Commits

Author SHA1 Message Date
Alexey Bataev 69a4779965 [OPENMP] Fixed codegen for 'reduction' clause.
Fixed codegen for reduction operations min, max, && and ||. Codegen for them is quite similar and I was confused by this similarity.
Also added a call to kmpc_end_reduce() in atomic part of reduction codegen (call to kmpc_end_reduce_nowait() is not required).
Differential Revision: http://reviews.llvm.org/D9513

llvm-svn: 236689
2015-05-07 03:54:03 +00:00
Alexey Bataev a89adf22db [OPENMP] Codegen for 'reduction' clause in 'sections' directive.
Emit a code for reduction clause. Next code should be emitted for reductions:

static kmp_critical_name lock = { 0 };

void reduce_func(void *lhs[<n>], void *rhs[<n>]) {
    *(Type0*)lhs[0] = ReductionOperation0(*(Type0*)lhs[0], *(Type0*)rhs[0]);
      ...
        *(Type<n>-1*)lhs[<n>-1] =
          ReductionOperation<n>-1(*(Type<n>-1*)lhs[<n>-1],
            *(Type<n>-1*)rhs[<n>-1]);
}

...
void *RedList[<n>] = {&<RHSExprs>[0], ..., &<RHSExprs>[<n>-1]};
switch (__kmpc_reduce{_nowait}(<loc>, <gtid>, <n>, sizeof(RedList), RedList, reduce_func, &<lock>)) {
case 1:
  <LHSExprs>[0] = ReductionOperation0(*<LHSExprs>[0], *<RHSExprs>[0]);
  ...
  <LHSExprs>[<n>-1] = ReductionOperation<n>-1(*<LHSExprs>[<n>-1], *<RHSExprs>[<n>-1]);
  __kmpc_end_reduce{_nowait}(<loc>, <gtid>, &<lock>);
  break;
case 2:
  Atomic(<LHSExprs>[0] = ReductionOperation0(*<LHSExprs>[0], *<RHSExprs>[0]));
  ...
  Atomic(<LHSExprs>[<n>-1] = ReductionOperation<n>-1(*<LHSExprs>[<n>-1], *<RHSExprs>[<n>-1]));
  break;
default:;
}
Reduction variables are a kind of a private variables, they have private copies, but initial values are chosen in accordance with the reduction operation.
If sections directive has only single section, then original shared variables are used instead with barrier at the end of the directive.
Differential Revision: http://reviews.llvm.org/D9242

llvm-svn: 235835
2015-04-27 05:04:13 +00:00