diff options
Diffstat (limited to 'gcc/tree-ssa-threadbackward.c')
| -rw-r--r-- | gcc/tree-ssa-threadbackward.c | 47 |
1 files changed, 8 insertions, 39 deletions
diff --git a/gcc/tree-ssa-threadbackward.c b/gcc/tree-ssa-threadbackward.c index 0f7b4a7..d067c47 100644 --- a/gcc/tree-ssa-threadbackward.c +++ b/gcc/tree-ssa-threadbackward.c @@ -91,7 +91,6 @@ private: edge maybe_register_path (); void maybe_register_path_dump (edge taken_edge); void find_paths_to_names (basic_block bb, bitmap imports); - bool resolve_def (tree name, bitmap interesting, vec<tree> &worklist); void resolve_phi (gphi *phi, bitmap imports); edge find_taken_edge (const vec<basic_block> &path); edge find_taken_edge_cond (const vec<basic_block> &path, gcond *); @@ -363,12 +362,8 @@ back_threader::resolve_phi (gphi *phi, bitmap interesting) edge e = gimple_phi_arg_edge (phi, i); // This is like path_crosses_loops in profitable_path_p but more - // restrictive, since profitable_path_p allows threading the - // first block because it would be redirected anyhow. - // - // If we loosened the restriction and used profitable_path_p() - // here instead, we would peel off the first iterations of loops - // in places like tree-ssa/pr14341.c. + // restrictive to avoid peeling off loop iterations (see + // tree-ssa/pr14341.c for an example). bool profitable_p = m_path[0]->loop_father == e->src->loop_father; if (!profitable_p) { @@ -404,33 +399,6 @@ back_threader::resolve_phi (gphi *phi, bitmap interesting) } } -// If the definition of NAME causes the final conditional of the -// current path to be constant, register the path, and return TRUE. - -bool -back_threader::resolve_def (tree name, bitmap interesting, vec<tree> &worklist) -{ - gimple *def_stmt = SSA_NAME_DEF_STMT (name); - - // Handle PHIs. - if (is_a<gphi *> (def_stmt)) - { - resolve_phi (as_a<gphi *> (def_stmt), interesting); - return true; - } - - // Defer copies of SSAs by adding the source to the worklist. - if (gimple_assign_single_p (def_stmt) - && TREE_CODE (gimple_assign_rhs1 (def_stmt)) == SSA_NAME) - { - tree rhs = gimple_assign_rhs1 (def_stmt); - bitmap_set_bit (m_imports, SSA_NAME_VERSION (rhs)); - bitmap_set_bit (interesting, SSA_NAME_VERSION (rhs)); - worklist.safe_push (rhs); - } - return false; -} - // Find jump threading paths to any of the SSA names in the // INTERESTING bitmap, and register any such paths. // @@ -464,13 +432,15 @@ back_threader::find_paths_to_names (basic_block bb, bitmap interesting) { tree name = worklist.pop (); unsigned i = SSA_NAME_VERSION (name); - basic_block def_bb = gimple_bb (SSA_NAME_DEF_STMT (name)); + gimple *def_stmt = SSA_NAME_DEF_STMT (name); + basic_block def_bb = gimple_bb (def_stmt); - // Process any names defined in this block. + // Process any PHIs defined in this block. if (def_bb == bb && bitmap_set_bit (processed, i) - && resolve_def (name, interesting, worklist)) + && gimple_code (def_stmt) == GIMPLE_PHI) { + resolve_phi (as_a<gphi *> (def_stmt), interesting); done = true; break; } @@ -515,10 +485,9 @@ back_threader::find_paths (basic_block bb, tree name) m_visited_bbs.empty (); m_path.truncate (0); m_name = name; - bitmap_clear (m_imports); + m_solver->compute_imports (m_imports, bb); auto_bitmap interesting; - bitmap_copy (m_imports, m_ranger->gori ().imports (bb)); bitmap_copy (interesting, m_imports); find_paths_to_names (bb, interesting); } |