diff options
Diffstat (limited to 'gcc/tree-ssa-dom.c')
| -rw-r--r-- | gcc/tree-ssa-dom.c | 64 |
1 files changed, 32 insertions, 32 deletions
diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c index db21218629e..dd9fd566785 100644 --- a/gcc/tree-ssa-dom.c +++ b/gcc/tree-ssa-dom.c @@ -83,7 +83,7 @@ struct cond_equivalence Computing and storing the edge equivalences instead of creating them on-demand can save significant amounts of time, particularly - for pathological cases involving switch statements. + for pathological cases involving switch statements. These structures live for a single iteration of the dominator optimizer in the edge's AUX field. At the end of an iteration we @@ -210,7 +210,7 @@ initialize_hash_element (gimple stmt, tree lhs, enum tree_code subcode = gimple_assign_rhs_code (stmt); expr->type = NULL_TREE; - + switch (get_gimple_rhs_class (subcode)) { case GIMPLE_SINGLE_RHS: @@ -255,7 +255,7 @@ initialize_hash_element (gimple stmt, tree lhs, if (gimple_call_flags (stmt) & (ECF_CONST | ECF_PURE)) expr->ops.call.pure = true; - else + else expr->ops.call.pure = false; expr->ops.call.nargs = nargs; @@ -293,7 +293,7 @@ static void initialize_expr_from_cond (tree cond, struct hashable_expr *expr) { expr->type = boolean_type_node; - + if (COMPARISON_CLASS_P (cond)) { expr->kind = EXPR_BINARY; @@ -415,7 +415,7 @@ hashable_expr_equal_p (const struct hashable_expr *expr0, return true; } - + default: gcc_unreachable (); } @@ -473,7 +473,7 @@ iterative_hash_hashable_expr (const struct hashable_expr *expr, hashval_t val) val = iterative_hash_expr (expr->ops.call.args[i], val); } break; - + default: gcc_unreachable (); } @@ -496,7 +496,7 @@ print_expr_hash_elt (FILE * stream, const struct expr_hash_elt *element) print_generic_expr (stream, element->lhs, 0); fprintf (stream, " = "); } - + switch (element->expr.kind) { case EXPR_SINGLE: @@ -597,7 +597,7 @@ free_all_edge_infos (void) } } -/* Jump threading, redundancy elimination and const/copy propagation. +/* Jump threading, redundancy elimination and const/copy propagation. This pass may expose new symbols that need to be renamed into SSA. For every new symbol exposed, its corresponding bit will be set in @@ -646,7 +646,7 @@ tree_ssa_dominator_optimize (void) for jump threading; this may include back edges that are not part of a single loop. */ mark_dfs_back_edges (); - + /* Recursively walk the dominator tree optimizing statements. */ walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR); @@ -720,10 +720,10 @@ tree_ssa_dominator_optimize (void) /* Free asserted bitmaps and stacks. */ BITMAP_FREE (need_eh_cleanup); - + VEC_free (expr_hash_elt_t, heap, avail_exprs_stack); VEC_free (tree, heap, const_and_copies_stack); - + /* Free the value-handle array. */ threadedge_finalize_values (); ssa_name_values = NULL; @@ -737,7 +737,7 @@ gate_dominator (void) return flag_tree_dom != 0; } -struct gimple_opt_pass pass_dominator = +struct gimple_opt_pass pass_dominator = { { GIMPLE_PASS, @@ -908,7 +908,7 @@ static void record_equivalences_from_phis (basic_block bb) { gimple_stmt_iterator gsi; - + for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { gimple phi = gsi_stmt (gsi); @@ -1094,7 +1094,7 @@ record_cond (struct cond_equivalence *p) /* Build a cond_equivalence record indicating that the comparison CODE holds between operands OP0 and OP1. */ - + static void build_and_record_new_cond (enum tree_code code, tree op0, tree op1, @@ -1371,7 +1371,7 @@ record_equality (tree x, tree y) /* Returns true when STMT is a simple iv increment. It detects the following situation: - + i_1 = phi (..., i_2) i_2 = i_1 +/- ... */ @@ -1410,7 +1410,7 @@ simple_iv_increment_p (gimple stmt) } /* CONST_AND_COPIES is a table which maps an SSA_NAME to the current - known value for that SSA_NAME (or NULL if no value is known). + known value for that SSA_NAME (or NULL if no value is known). Propagate values from CONST_AND_COPIES into the PHI nodes of the successors of BB. */ @@ -1846,7 +1846,7 @@ eliminate_redundant_computations (gimple_stmt_iterator* gsi) } opt_stats.num_re++; - + if (assigns_var_p && !useless_type_conversion_p (expr_type, TREE_TYPE (cached_lhs))) cached_lhs = fold_convert (expr_type, cached_lhs); @@ -1881,7 +1881,7 @@ record_equivalences_from_stmt (gimple stmt, int may_optimize_p) && gimple_assign_single_p (stmt)) { tree rhs = gimple_assign_rhs1 (stmt); - + /* If the RHS of the assignment is a constant or another variable that may be propagated, register it in the CONST_AND_COPIES table. We do not need to record unwind data for this, since this is a true @@ -2031,7 +2031,7 @@ cprop_operand (gimple stmt, use_operand_p op_p) } /* CONST_AND_COPIES is a table which maps an SSA_NAME to the current - known value for that SSA_NAME (or NULL if no value is known). + known value for that SSA_NAME (or NULL if no value is known). Propagate values from CONST_AND_COPIES into the uses, vuses and vdef_ops of STMT. */ @@ -2050,7 +2050,7 @@ cprop_into_stmt (gimple stmt) } /* Optimize the statement pointed to by iterator SI. - + We try to perform some simplistic global redundancy elimination and constant propagation: @@ -2072,10 +2072,10 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si) bool modified_p = false; old_stmt = stmt = gsi_stmt (si); - + if (gimple_code (stmt) == GIMPLE_COND) canonicalize_comparison (stmt); - + update_stmt_if_modified (stmt); opt_stats.num_stmts++; @@ -2167,7 +2167,7 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si) where it goes. If that is the case, then mark the CFG as altered. This will cause us to later call remove_unreachable_blocks and - cleanup_tree_cfg when it is safe to do so. It is not safe to + cleanup_tree_cfg when it is safe to do so. It is not safe to clean things up here since removal of edges and such can trigger the removal of PHI nodes, which in turn can release SSA_NAMEs to the manager. @@ -2191,7 +2191,7 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si) if (gimple_modified_p (stmt) || modified_p) { tree val = NULL; - + update_stmt_if_modified (stmt); if (gimple_code (stmt) == GIMPLE_COND) @@ -2259,7 +2259,7 @@ lookup_avail_expr (gimple stmt, bool insert) if (slot == NULL) { free (element); - return NULL_TREE; + return NULL_TREE; } if (*slot == NULL) @@ -2469,7 +2469,7 @@ get_lhs_or_phi_result (gimple stmt) nodes as well in an effort to pick up secondary optimization opportunities. */ -static void +static void propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_names) { /* First verify that propagation is valid and isn't going to move a @@ -2496,7 +2496,7 @@ propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_name fprintf (dump_file, "'\n"); } - /* Walk over every use of LHS and try to replace the use with RHS. + /* Walk over every use of LHS and try to replace the use with RHS. At this point the only reason why such a propagation would not be successful would be if the use occurs in an ASM_EXPR. */ FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs) @@ -2506,7 +2506,7 @@ propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_name into debug stmts will occur then. */ if (gimple_debug_bind_p (use_stmt)) continue; - + /* It's not always safe to propagate into an ASM_EXPR. */ if (gimple_code (use_stmt) == GIMPLE_ASM && ! may_propagate_copy_into_asm (lhs)) @@ -2559,7 +2559,7 @@ propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_name continue; } - /* From this point onward we are propagating into a + /* From this point onward we are propagating into a real statement. Folding may (or may not) be possible, we may expose new operands, expose dead EH edges, etc. */ @@ -2680,7 +2680,7 @@ propagate_rhs_into_lhs (gimple stmt, tree lhs, tree rhs, bitmap interesting_name } } - /* Ensure there is nothing else to do. */ + /* Ensure there is nothing else to do. */ gcc_assert (!all || has_zero_uses (lhs)); /* If we were able to propagate away all uses of LHS, then @@ -2804,7 +2804,7 @@ eliminate_degenerate_phis (void) A set bit indicates that the statement or PHI node which defines the SSA_NAME should be (re)examined to determine if it has become a degenerate PHI or trivial const/copy propagation - opportunity. + opportunity. Experiments have show we generally get better compilation time behavior with bitmaps rather than sbitmaps. */ @@ -2882,7 +2882,7 @@ struct gimple_opt_pass pass_phi_only_cprop = 0, /* properties_destroyed */ 0, /* todo_flags_start */ TODO_cleanup_cfg - | TODO_dump_func + | TODO_dump_func | TODO_ggc_collect | TODO_verify_ssa | TODO_verify_stmts |