Sort static functions in topological order.
2010-04-07 Sebastian Pop <sebastian.pop@amd.com> * tree-if-conv.c: Sort static functions in topological order. From-SVN: r158040
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Sebastian Pop
Sebastian Pop
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2 changed files with 285 additions and 316 deletions
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@ -1,3 +1,7 @@
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2010-04-07 Sebastian Pop <sebastian.pop@amd.com>
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* tree-if-conv.c: Sort static functions in topological order.
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2010-04-07 Sebastian Pop <sebastian.pop@amd.com>
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* tree-if-conv.c: Fix indentation and comments.
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@ -100,119 +100,150 @@ along with GCC; see the file COPYING3. If not see
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#include "tree-pass.h"
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#include "target.h"
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/* local function prototypes */
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static unsigned int main_tree_if_conversion (void);
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static tree tree_if_convert_stmt (struct loop *loop, gimple, tree,
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gimple_stmt_iterator *);
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static void tree_if_convert_cond_stmt (struct loop *, gimple, tree,
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gimple_stmt_iterator *);
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static bool if_convertible_phi_p (struct loop *, basic_block, gimple);
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static bool if_convertible_gimple_assign_stmt_p (struct loop *, basic_block,
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gimple);
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static bool if_convertible_stmt_p (struct loop *, basic_block, gimple);
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static bool if_convertible_bb_p (struct loop *, basic_block, basic_block);
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static bool if_convertible_loop_p (struct loop *, bool);
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static void add_to_predicate_list (basic_block, tree);
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static tree add_to_dst_predicate_list (struct loop * loop, edge,
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tree, tree,
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gimple_stmt_iterator *);
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static void clean_predicate_lists (struct loop *loop);
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static basic_block find_phi_replacement_condition (struct loop *loop,
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basic_block, tree *,
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gimple_stmt_iterator *);
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static void replace_phi_with_cond_gimple_assign_stmt (gimple, tree,
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basic_block,
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gimple_stmt_iterator *);
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static void process_phi_nodes (struct loop *);
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static void combine_blocks (struct loop *);
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static gimple ifc_temp_var (tree, tree);
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static bool pred_blocks_visited_p (basic_block, bitmap *);
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static basic_block * get_loop_body_in_if_conv_order (const struct loop *loop);
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static bool bb_with_exit_edge_p (struct loop *, basic_block);
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/* List of basic blocks in if-conversion-suitable order. */
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static basic_block *ifc_bbs;
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/* Main entry point. Apply if-conversion to the LOOP. Return true if
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successful otherwise return false. If false is returned then loop
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remains unchanged. FOR_VECTORIZER is a boolean flag. It indicates
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whether if-conversion is used for vectorizer or not. If it is used
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for vectorizer, additional checks are used. (Vectorization checks
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are not yet implemented). */
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/* Make a new temp variable of type TYPE. Add GIMPLE_ASSIGN to assign EXP
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to the new variable. */
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static gimple
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ifc_temp_var (tree type, tree exp)
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{
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const char *name = "_ifc_";
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tree var, new_name;
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gimple stmt;
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/* Create new temporary variable. */
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var = create_tmp_var (type, name);
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add_referenced_var (var);
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/* Build new statement to assign EXP to new variable. */
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stmt = gimple_build_assign (var, exp);
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/* Get SSA name for the new variable and set make new statement
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its definition statement. */
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new_name = make_ssa_name (var, stmt);
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gimple_assign_set_lhs (stmt, new_name);
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SSA_NAME_DEF_STMT (new_name) = stmt;
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update_stmt (stmt);
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return stmt;
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}
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/* Add condition COND into predicate list of basic block BB. */
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static void
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add_to_predicate_list (basic_block bb, tree new_cond)
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{
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tree cond = (tree) bb->aux;
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if (cond)
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cond = fold_build2_loc (EXPR_LOCATION (cond),
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TRUTH_OR_EXPR, boolean_type_node,
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unshare_expr (cond), new_cond);
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else
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cond = new_cond;
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bb->aux = cond;
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}
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/* Add condition COND into BB's predicate list. PREV_COND is
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existing condition. */
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static tree
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add_to_dst_predicate_list (struct loop *loop, edge e,
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tree prev_cond, tree cond,
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gimple_stmt_iterator *gsi)
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{
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tree new_cond = NULL_TREE;
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if (!flow_bb_inside_loop_p (loop, e->dest))
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return NULL_TREE;
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if (prev_cond == boolean_true_node || !prev_cond)
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new_cond = unshare_expr (cond);
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else
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{
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tree tmp;
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gimple tmp_stmt = NULL;
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prev_cond = force_gimple_operand_gsi (gsi, unshare_expr (prev_cond),
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true, NULL, true, GSI_SAME_STMT);
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cond = force_gimple_operand_gsi (gsi, unshare_expr (cond),
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true, NULL, true, GSI_SAME_STMT);
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/* Add the condition to aux field of the edge. In case edge
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destination is a PHI node, this condition will be ANDed with
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block predicate to construct complete condition. */
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e->aux = cond;
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tmp = build2 (TRUTH_AND_EXPR, boolean_type_node,
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unshare_expr (prev_cond), cond);
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tmp_stmt = ifc_temp_var (boolean_type_node, tmp);
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gsi_insert_before (gsi, tmp_stmt, GSI_SAME_STMT);
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new_cond = gimple_assign_lhs (tmp_stmt);
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}
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add_to_predicate_list (e->dest, new_cond);
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return new_cond;
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}
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/* Return true if one of the basic block BB edge is exit of LOOP. */
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static bool
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tree_if_conversion (struct loop *loop, bool for_vectorizer)
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bb_with_exit_edge_p (struct loop *loop, basic_block bb)
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{
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basic_block bb;
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gimple_stmt_iterator itr;
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unsigned int i;
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edge e;
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edge_iterator ei;
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bool exit_edge_found = false;
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ifc_bbs = NULL;
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FOR_EACH_EDGE (e, ei, bb->succs)
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if (loop_exit_edge_p (loop, e))
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{
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exit_edge_found = true;
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break;
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}
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/* If-conversion is not appropriate for all loops. First, check if
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loop is if-convertible or not. */
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if (!if_convertible_loop_p (loop, for_vectorizer))
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return exit_edge_found;
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}
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/* STMT is a GIMPLE_COND. Update two destination's predicate list.
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Remove COND_EXPR, if it is not the loop exit condition. Otherwise
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update loop exit condition appropriately. GSI is the iterator
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used to traverse statement list. STMT is part of loop LOOP. */
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static void
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tree_if_convert_cond_stmt (struct loop *loop, gimple stmt, tree cond,
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gimple_stmt_iterator *gsi)
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{
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tree c2;
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edge true_edge, false_edge;
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location_t loc = gimple_location (stmt);
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tree c = fold_build2_loc (loc, gimple_cond_code (stmt), boolean_type_node,
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gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
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extract_true_false_edges_from_block (gimple_bb (stmt),
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&true_edge, &false_edge);
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/* Add new condition into destination's predicate list. */
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/* If C is true, then TRUE_EDGE is taken. */
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add_to_dst_predicate_list (loop, true_edge, cond, c, gsi);
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/* If C is false, then FALSE_EDGE is taken. */
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c2 = invert_truthvalue_loc (loc, unshare_expr (c));
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add_to_dst_predicate_list (loop, false_edge, cond, c2, gsi);
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/* Now this conditional statement is redundant. Remove it.
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But, do not remove exit condition! Update exit condition
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using new condition. */
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if (!bb_with_exit_edge_p (loop, gimple_bb (stmt)))
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{
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if (dump_file && (dump_flags & TDF_DETAILS))
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fprintf (dump_file,"-------------------------\n");
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if (ifc_bbs)
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{
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free (ifc_bbs);
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ifc_bbs = NULL;
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}
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free_dominance_info (CDI_POST_DOMINATORS);
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return false;
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gsi_remove (gsi, true);
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cond = NULL_TREE;
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}
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/* Do actual work now. */
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for (i = 0; i < loop->num_nodes; i++)
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{
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tree cond;
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bb = ifc_bbs [i];
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/* Update condition using predicate list. */
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cond = (tree) bb->aux;
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/* Process all statements in this basic block.
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Remove conditional expression, if any, and annotate
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destination basic block(s) appropriately. */
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for (itr = gsi_start_bb (bb); !gsi_end_p (itr); /* empty */)
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{
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gimple t = gsi_stmt (itr);
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cond = tree_if_convert_stmt (loop, t, cond, &itr);
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if (!gsi_end_p (itr))
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gsi_next (&itr);
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}
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/* If current bb has only one successor, then consider it as an
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unconditional goto. */
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if (single_succ_p (bb))
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{
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basic_block bb_n = single_succ (bb);
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/* Successor bb inherits predicate of its predecessor. If there
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is no predicate in predecessor bb, then consider successor bb
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as always executed. */
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if (cond == NULL_TREE)
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cond = boolean_true_node;
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add_to_predicate_list (bb_n, cond);
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}
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}
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/* Now, all statements are if-converted and basic blocks are
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annotated appropriately. Combine all basic block into one huge
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basic block. */
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combine_blocks (loop);
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/* clean up */
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clean_predicate_lists (loop);
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free (ifc_bbs);
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ifc_bbs = NULL;
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return true;
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return;
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}
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/* If-convert stmt T which is part of LOOP.
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@ -269,47 +300,6 @@ tree_if_convert_stmt (struct loop * loop, gimple t, tree cond,
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return cond;
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}
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/* STMT is a GIMPLE_COND. Update two destination's predicate list.
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Remove COND_EXPR, if it is not the loop exit condition. Otherwise
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update loop exit condition appropriately. GSI is the iterator
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used to traverse statement list. STMT is part of loop LOOP. */
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static void
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tree_if_convert_cond_stmt (struct loop *loop, gimple stmt, tree cond,
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gimple_stmt_iterator *gsi)
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{
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tree c, c2;
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edge true_edge, false_edge;
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location_t loc = gimple_location (stmt);
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gcc_assert (gimple_code (stmt) == GIMPLE_COND);
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c = fold_build2_loc (loc, gimple_cond_code (stmt), boolean_type_node,
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gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
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extract_true_false_edges_from_block (gimple_bb (stmt),
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&true_edge, &false_edge);
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/* Add new condition into destination's predicate list. */
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/* If C is true, then TRUE_EDGE is taken. */
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add_to_dst_predicate_list (loop, true_edge, cond, c, gsi);
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/* If C is false, then FALSE_EDGE is taken. */
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c2 = invert_truthvalue_loc (loc, unshare_expr (c));
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add_to_dst_predicate_list (loop, false_edge, cond, c2, gsi);
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/* Now this conditional statement is redundant. Remove it.
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But, do not remove exit condition! Update exit condition
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using new condition. */
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if (!bb_with_exit_edge_p (loop, gimple_bb (stmt)))
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{
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gsi_remove (gsi, true);
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cond = NULL_TREE;
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}
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return;
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}
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/* Return true, iff PHI is if-convertible. PHI is part of loop LOOP
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and it belongs to basic block BB.
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PHI is not if-convertible
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@ -512,6 +502,80 @@ if_convertible_bb_p (struct loop *loop, basic_block bb, basic_block exit_bb)
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return true;
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}
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/* Return TRUE iff, all pred blocks of BB are visited.
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Bitmap VISITED keeps history of visited blocks. */
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static bool
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pred_blocks_visited_p (basic_block bb, bitmap *visited)
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{
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edge e;
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edge_iterator ei;
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FOR_EACH_EDGE (e, ei, bb->preds)
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if (!bitmap_bit_p (*visited, e->src->index))
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return false;
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return true;
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}
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/* Get body of a LOOP in suitable order for if-conversion. It is
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caller's responsibility to deallocate basic block list.
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If-conversion suitable order is, breadth first sort (BFS) order
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with an additional constraint: select a block only if all its
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predecessors are already selected. */
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static basic_block *
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get_loop_body_in_if_conv_order (const struct loop *loop)
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{
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basic_block *blocks, *blocks_in_bfs_order;
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basic_block bb;
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bitmap visited;
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unsigned int index = 0;
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unsigned int visited_count = 0;
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gcc_assert (loop->num_nodes);
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gcc_assert (loop->latch != EXIT_BLOCK_PTR);
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blocks = XCNEWVEC (basic_block, loop->num_nodes);
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visited = BITMAP_ALLOC (NULL);
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blocks_in_bfs_order = get_loop_body_in_bfs_order (loop);
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index = 0;
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while (index < loop->num_nodes)
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{
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bb = blocks_in_bfs_order [index];
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if (bb->flags & BB_IRREDUCIBLE_LOOP)
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{
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free (blocks_in_bfs_order);
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BITMAP_FREE (visited);
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free (blocks);
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return NULL;
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}
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if (!bitmap_bit_p (visited, bb->index))
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{
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if (pred_blocks_visited_p (bb, &visited)
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|| bb == loop->header)
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{
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/* This block is now visited. */
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bitmap_set_bit (visited, bb->index);
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blocks[visited_count++] = bb;
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}
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}
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index++;
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if (index == loop->num_nodes
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&& visited_count != loop->num_nodes)
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/* Not done yet. */
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index = 0;
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}
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free (blocks_in_bfs_order);
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BITMAP_FREE (visited);
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return blocks;
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}
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/* Return true, iff LOOP is if-convertible.
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LOOP is if-convertible if:
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- it is innermost,
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@ -613,65 +677,6 @@ if_convertible_loop_p (struct loop *loop, bool for_vectorizer ATTRIBUTE_UNUSED)
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return true;
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}
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/* Add condition COND into predicate list of basic block BB. */
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static void
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add_to_predicate_list (basic_block bb, tree new_cond)
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{
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tree cond = (tree) bb->aux;
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if (cond)
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cond = fold_build2_loc (EXPR_LOCATION (cond),
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TRUTH_OR_EXPR, boolean_type_node,
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unshare_expr (cond), new_cond);
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else
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cond = new_cond;
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bb->aux = cond;
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}
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/* Add condition COND into BB's predicate list. PREV_COND is
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existing condition. */
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static tree
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add_to_dst_predicate_list (struct loop * loop, edge e,
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tree prev_cond, tree cond,
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gimple_stmt_iterator *gsi)
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{
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tree new_cond = NULL_TREE;
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if (!flow_bb_inside_loop_p (loop, e->dest))
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return NULL_TREE;
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if (prev_cond == boolean_true_node || !prev_cond)
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new_cond = unshare_expr (cond);
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else
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{
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tree tmp;
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gimple tmp_stmt = NULL;
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prev_cond = force_gimple_operand_gsi (gsi, unshare_expr (prev_cond),
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true, NULL, true, GSI_SAME_STMT);
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cond = force_gimple_operand_gsi (gsi, unshare_expr (cond),
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true, NULL, true, GSI_SAME_STMT);
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/* Add the condition to aux field of the edge. In case edge
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destination is a PHI node, this condition will be ANDed with
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block predicate to construct complete condition. */
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e->aux = cond;
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/* new_cond == prev_cond AND cond */
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tmp = build2 (TRUTH_AND_EXPR, boolean_type_node,
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unshare_expr (prev_cond), cond);
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tmp_stmt = ifc_temp_var (boolean_type_node, tmp);
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gsi_insert_before (gsi, tmp_stmt, GSI_SAME_STMT);
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new_cond = gimple_assign_lhs (tmp_stmt);
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}
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add_to_predicate_list (e->dest, new_cond);
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return new_cond;
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}
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/* During if-conversion aux field from basic block structure is used to hold
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predicate list. Clean each basic block's predicate list for the given LOOP.
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Also clean aux field of successor edges, used to hold true and false
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@ -1015,127 +1020,87 @@ combine_blocks (struct loop *loop)
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merge_blocks (loop->header, exit_bb);
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}
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/* Make a new temp variable of type TYPE. Add GIMPLE_ASSIGN to assign EXP
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to the new variable. */
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static gimple
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ifc_temp_var (tree type, tree exp)
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{
|
||||
const char *name = "_ifc_";
|
||||
tree var, new_name;
|
||||
gimple stmt;
|
||||
|
||||
/* Create new temporary variable. */
|
||||
var = create_tmp_var (type, name);
|
||||
add_referenced_var (var);
|
||||
|
||||
/* Build new statement to assign EXP to new variable. */
|
||||
stmt = gimple_build_assign (var, exp);
|
||||
|
||||
/* Get SSA name for the new variable and set make new statement
|
||||
its definition statement. */
|
||||
new_name = make_ssa_name (var, stmt);
|
||||
gimple_assign_set_lhs (stmt, new_name);
|
||||
SSA_NAME_DEF_STMT (new_name) = stmt;
|
||||
update_stmt (stmt);
|
||||
|
||||
return stmt;
|
||||
}
|
||||
|
||||
|
||||
/* Return TRUE iff, all pred blocks of BB are visited.
|
||||
Bitmap VISITED keeps history of visited blocks. */
|
||||
/* Main entry point. Apply if-conversion to the LOOP. Return true if
|
||||
successful otherwise return false. If false is returned then loop
|
||||
remains unchanged. FOR_VECTORIZER is a boolean flag. It indicates
|
||||
whether if-conversion is used for vectorizer or not. If it is used
|
||||
for vectorizer, additional checks are used. (Vectorization checks
|
||||
are not yet implemented). */
|
||||
|
||||
static bool
|
||||
pred_blocks_visited_p (basic_block bb, bitmap *visited)
|
||||
tree_if_conversion (struct loop *loop, bool for_vectorizer)
|
||||
{
|
||||
edge e;
|
||||
edge_iterator ei;
|
||||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||||
if (!bitmap_bit_p (*visited, e->src->index))
|
||||
basic_block bb;
|
||||
gimple_stmt_iterator itr;
|
||||
unsigned int i;
|
||||
|
||||
ifc_bbs = NULL;
|
||||
|
||||
/* If-conversion is not appropriate for all loops. First, check if
|
||||
loop is if-convertible or not. */
|
||||
if (!if_convertible_loop_p (loop, for_vectorizer))
|
||||
{
|
||||
if (dump_file && (dump_flags & TDF_DETAILS))
|
||||
fprintf (dump_file,"-------------------------\n");
|
||||
if (ifc_bbs)
|
||||
{
|
||||
free (ifc_bbs);
|
||||
ifc_bbs = NULL;
|
||||
}
|
||||
free_dominance_info (CDI_POST_DOMINATORS);
|
||||
return false;
|
||||
}
|
||||
|
||||
/* Do actual work now. */
|
||||
for (i = 0; i < loop->num_nodes; i++)
|
||||
{
|
||||
tree cond;
|
||||
|
||||
bb = ifc_bbs [i];
|
||||
|
||||
/* Update condition using predicate list. */
|
||||
cond = (tree) bb->aux;
|
||||
|
||||
/* Process all statements in this basic block.
|
||||
Remove conditional expression, if any, and annotate
|
||||
destination basic block(s) appropriately. */
|
||||
for (itr = gsi_start_bb (bb); !gsi_end_p (itr); /* empty */)
|
||||
{
|
||||
gimple t = gsi_stmt (itr);
|
||||
cond = tree_if_convert_stmt (loop, t, cond, &itr);
|
||||
if (!gsi_end_p (itr))
|
||||
gsi_next (&itr);
|
||||
}
|
||||
|
||||
/* If current bb has only one successor, then consider it as an
|
||||
unconditional goto. */
|
||||
if (single_succ_p (bb))
|
||||
{
|
||||
basic_block bb_n = single_succ (bb);
|
||||
|
||||
/* Successor bb inherits predicate of its predecessor. If there
|
||||
is no predicate in predecessor bb, then consider successor bb
|
||||
as always executed. */
|
||||
if (cond == NULL_TREE)
|
||||
cond = boolean_true_node;
|
||||
|
||||
add_to_predicate_list (bb_n, cond);
|
||||
}
|
||||
}
|
||||
|
||||
/* Now, all statements are if-converted and basic blocks are
|
||||
annotated appropriately. Combine all basic block into one huge
|
||||
basic block. */
|
||||
combine_blocks (loop);
|
||||
|
||||
/* clean up */
|
||||
clean_predicate_lists (loop);
|
||||
free (ifc_bbs);
|
||||
ifc_bbs = NULL;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
/* Get body of a LOOP in suitable order for if-conversion. It is
|
||||
caller's responsibility to deallocate basic block list.
|
||||
If-conversion suitable order is, breadth first sort (BFS) order
|
||||
with an additional constraint: select a block only if all its
|
||||
predecessors are already selected. */
|
||||
|
||||
static basic_block *
|
||||
get_loop_body_in_if_conv_order (const struct loop *loop)
|
||||
{
|
||||
basic_block *blocks, *blocks_in_bfs_order;
|
||||
basic_block bb;
|
||||
bitmap visited;
|
||||
unsigned int index = 0;
|
||||
unsigned int visited_count = 0;
|
||||
|
||||
gcc_assert (loop->num_nodes);
|
||||
gcc_assert (loop->latch != EXIT_BLOCK_PTR);
|
||||
|
||||
blocks = XCNEWVEC (basic_block, loop->num_nodes);
|
||||
visited = BITMAP_ALLOC (NULL);
|
||||
|
||||
blocks_in_bfs_order = get_loop_body_in_bfs_order (loop);
|
||||
|
||||
index = 0;
|
||||
while (index < loop->num_nodes)
|
||||
{
|
||||
bb = blocks_in_bfs_order [index];
|
||||
|
||||
if (bb->flags & BB_IRREDUCIBLE_LOOP)
|
||||
{
|
||||
free (blocks_in_bfs_order);
|
||||
BITMAP_FREE (visited);
|
||||
free (blocks);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
if (!bitmap_bit_p (visited, bb->index))
|
||||
{
|
||||
if (pred_blocks_visited_p (bb, &visited)
|
||||
|| bb == loop->header)
|
||||
{
|
||||
/* This block is now visited. */
|
||||
bitmap_set_bit (visited, bb->index);
|
||||
blocks[visited_count++] = bb;
|
||||
}
|
||||
}
|
||||
|
||||
index++;
|
||||
|
||||
if (index == loop->num_nodes
|
||||
&& visited_count != loop->num_nodes)
|
||||
/* Not done yet. */
|
||||
index = 0;
|
||||
}
|
||||
free (blocks_in_bfs_order);
|
||||
BITMAP_FREE (visited);
|
||||
return blocks;
|
||||
}
|
||||
|
||||
/* Return true if one of the basic block BB edge is exit of LOOP. */
|
||||
|
||||
static bool
|
||||
bb_with_exit_edge_p (struct loop *loop, basic_block bb)
|
||||
{
|
||||
edge e;
|
||||
edge_iterator ei;
|
||||
bool exit_edge_found = false;
|
||||
|
||||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||||
if (loop_exit_edge_p (loop, e))
|
||||
{
|
||||
exit_edge_found = true;
|
||||
break;
|
||||
}
|
||||
|
||||
return exit_edge_found;
|
||||
}
|
||||
|
||||
/* Tree if-conversion pass management. */
|
||||
|
||||
static unsigned int
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue