diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 84928803e9e..a9f74afcc1a 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,7 @@ +2012-05-20 Razya Ladelsky + + * tree-parloops.c (gen_parallel_loop): Change many_iterations_cond for outer loops. + 2012-05-18 Jan Hubicka * cgraphunit.c (handle_alias_pairs): Declare; free alias_pairs diff --git a/gcc/tree-parloops.c b/gcc/tree-parloops.c index 18bf645366e..7c1e462a0fb 100644 --- a/gcc/tree-parloops.c +++ b/gcc/tree-parloops.c @@ -1732,6 +1732,7 @@ gen_parallel_loop (struct loop *loop, htab_t reduction_list, unsigned prob; location_t loc; gimple cond_stmt; + unsigned int m_p_thread=2; /* From @@ -1786,15 +1787,31 @@ gen_parallel_loop (struct loop *loop, htab_t reduction_list, loop that will be split to loop_fn, the new one will be used for the remaining iterations. */ + /* We should compute a better number-of-iterations value for outer loops. + That is, if we have + + for (i = 0; i < n; ++i) + for (j = 0; j < m; ++j) + ... + + we should compute nit = n * m, not nit = n. + Also may_be_zero handling would need to be adjusted. */ + type = TREE_TYPE (niter->niter); nit = force_gimple_operand (unshare_expr (niter->niter), &stmts, true, NULL_TREE); if (stmts) gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts); - many_iterations_cond = - fold_build2 (GE_EXPR, boolean_type_node, - nit, build_int_cst (type, MIN_PER_THREAD * n_threads)); + if (loop->inner) + m_p_thread=2; + else + m_p_thread=MIN_PER_THREAD; + + many_iterations_cond = + fold_build2 (GE_EXPR, boolean_type_node, + nit, build_int_cst (type, m_p_thread * n_threads)); + many_iterations_cond = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, invert_truthvalue (unshare_expr (niter->may_be_zero)),