You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
-#include "errors.h"
#include "ggc.h"
#include "tree.h"
#include "basic-block.h"
if (op2)
genop2 = find_or_generate_expression (block, op2, stmts);
- folded = fold (build (TREE_CODE (expr), TREE_TYPE (expr),
- genop0, genarglist, genop2));
+ folded = fold_build3 (TREE_CODE (expr), TREE_TYPE (expr),
+ genop0, genarglist, genop2);
break;
tree op2 = TREE_OPERAND (expr, 1);
tree genop1 = find_or_generate_expression (block, op1, stmts);
tree genop2 = find_or_generate_expression (block, op2, stmts);
- folded = fold (build (TREE_CODE (expr), TREE_TYPE (expr),
- genop1, genop2));
+ folded = fold_build2 (TREE_CODE (expr), TREE_TYPE (expr),
+ genop1, genop2);
break;
}
{
tree op1 = TREE_OPERAND (expr, 0);
tree genop1 = find_or_generate_expression (block, op1, stmts);
- folded = fold (build (TREE_CODE (expr), TREE_TYPE (expr),
- genop1));
+ folded = fold_build1 (TREE_CODE (expr), TREE_TYPE (expr),
+ genop1);
break;
}
that we will return. */
temp = create_tmp_var (TREE_TYPE (expr), "pretmp");
add_referenced_tmp_var (temp);
+ if (TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE)
+ DECL_COMPLEX_GIMPLE_REG_P (temp) = 1;
newexpr = build (MODIFY_EXPR, TREE_TYPE (expr), temp, newexpr);
name = make_ssa_name (temp, newexpr);
TREE_OPERAND (newexpr, 0) = name;
/* Now build a phi for the new variable. */
temp = create_tmp_var (type, tmpname);
add_referenced_tmp_var (temp);
+ if (TREE_CODE (type) == COMPLEX_TYPE)
+ DECL_COMPLEX_GIMPLE_REG_P (temp) = 1;
temp = create_phi_node (temp, block);
NECESSARY (temp) = 0;
VEC_safe_push (tree, heap, inserted_exprs, temp);
fprintf (dump_file, " in ");
print_generic_stmt (dump_file, stmt, 0);
}
+
if (TREE_CODE (sprime) == SSA_NAME)
NECESSARY (SSA_NAME_DEF_STMT (sprime)) = 1;
+ /* We need to make sure the new and old types actually match,
+ which may require adding a simple cast, which fold_convert
+ will do for us. */
+ if (TREE_CODE (*rhs_p) != SSA_NAME
+ && !tree_ssa_useless_type_conversion_1 (TREE_TYPE (*rhs_p),
+ TREE_TYPE (sprime)))
+ sprime = fold_convert (TREE_TYPE (*rhs_p), sprime);
+
pre_stats.eliminations++;
propagate_tree_value (rhs_p, sprime);
update_stmt (stmt);
TODO_dump_func | TODO_ggc_collect | TODO_verify_ssa, /* todo_flags_finish */
0 /* letter */
};
+
+/* Return true if T is a copy statement between two ssa names. */
+
+static bool
+is_copy_stmt (tree t)
+{
+ if (!t || TREE_CODE (t) != MODIFY_EXPR)
+ return false;
+ if (TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME
+ && TREE_CODE (TREE_OPERAND (t, 1)) == SSA_NAME)
+ return true;
+ return false;
+}
+
+/* Starting from START, walk copy statements till we hit a statement with a
+ VUSE or a non-copy statement. */
+
+static tree
+follow_copies_till_vuse (tree start)
+{
+ if (is_copy_stmt (start) && ZERO_SSA_OPERANDS (start, SSA_OP_VIRTUAL_USES))
+ {
+ tree rhs, defstmt;
+
+ rhs = TREE_OPERAND (start, 1);
+ defstmt = SSA_NAME_DEF_STMT (rhs);
+ return follow_copies_till_vuse (defstmt);
+ }
+ return start;
+}
+
+/* Gate and execute functions for eliminate useless stores.
+ The goal here is to recognize the pattern *x = ... *x, and eliminate the
+ store because the value hasn't changed. Store copy/const prop won't
+ do this because making *more* loads (IE propagating *x) is not a win, so it
+ ignores them.
+ This pass is currently geared completely towards static variable store
+ elimination. */
+
+static void
+do_eustores (void)
+{
+ basic_block bb;
+ /* For each basic block
+ For each statement (STMT) in the block
+ if STMT is a stores of the pattern *x = y
+ follow the chain of definitions for y, until we hit a non-copy
+ statement or a statement with a vuse.
+ if the statement we arrive at is a vuse of the operand we killed,
+ accessed through the same memory operation, then we have a
+ useless store (because it is *x = ... = *x). */
+
+ FOR_EACH_BB (bb)
+ {
+ block_stmt_iterator bsi;
+
+ for (bsi = bsi_start (bb);
+ !bsi_end_p (bsi);)
+ {
+ tree stmt = bsi_stmt (bsi);
+ tree startat;
+ tree kill;
+ tree found;
+
+ if (NUM_SSA_OPERANDS (stmt, SSA_OP_VMUSTDEF) != 1
+ || TREE_CODE (stmt) != MODIFY_EXPR
+ || TREE_CODE (TREE_OPERAND (stmt, 1)) != SSA_NAME)
+ {
+ bsi_next (&bsi);
+ continue;
+ }
+
+ kill = MUSTDEF_KILL (MUSTDEF_OPS (stmt));
+ startat = TREE_OPERAND (stmt, 1);
+ startat = SSA_NAME_DEF_STMT (startat);
+ found = follow_copies_till_vuse (startat);
+
+ if (found && TREE_CODE (found) == MODIFY_EXPR)
+ {
+
+ /* We want exactly one virtual use, and it should match up with
+ the use being killed. */
+
+ if (NUM_SSA_OPERANDS (found, SSA_OP_VUSE) != 1
+ || VUSE_OP (VUSE_OPS (found)) != kill
+ || !DECL_P (TREE_OPERAND (stmt, 0))
+ || !operand_equal_p (TREE_OPERAND (found, 1),
+ TREE_OPERAND (stmt, 0), 0))
+ {
+ bsi_next (&bsi);
+ continue;
+ }
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "Eliminating useless store ");
+ print_generic_stmt (dump_file, stmt, 0);
+ }
+ mark_sym_for_renaming (TREE_OPERAND (stmt, 0));
+ bsi_remove (&bsi);
+ }
+ else
+ {
+ bsi_next (&bsi);
+ continue;
+ }
+ }
+ }
+}
+
+static bool
+gate_eustores(void)
+{
+ return flag_unit_at_a_time != 0;
+}
+
+struct tree_opt_pass pass_eliminate_useless_stores =
+{
+ "eustores", /* name */
+ gate_eustores, /* gate */
+ do_eustores, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ 0, /* tv_id */
+ PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_update_ssa | TODO_dump_func
+ | TODO_ggc_collect | TODO_verify_ssa, /* todo_flags_finish */
+ 0 /* letter */
+};
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