+/*
+ * Copyright (C) 1995-2011 University of Karlsruhe. All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
+ *
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
+ */
+
+/**
+ * @file
+ * @brief doubleword lowering operations
+ * @author Michael Beck, Matthias Braun
+ */
+#ifndef FIRM_LOWER_LOWER_DW_H
+#define FIRM_LOWER_LOWER_DW_H
+
+/**
+ * Every double word node will be replaced,
+ * we need some store to hold the replacement:
+ */
+typedef struct lower64_entry_t {
+ ir_node *low_word; /**< the low word */
+ ir_node *high_word; /**< the high word */
+} lower64_entry_t;
+
+
+/**
+ * A callback type for creating an intrinsic entity for a given opcode.
+ *
+ * @param method the method type of the emulation function entity
+ * @param op the emulated ir_op
+ * @param imode the input mode of the emulated opcode
+ * @param omode the output mode of the emulated opcode
+ * @param context the context parameter
+ */
+typedef ir_entity *(create_intrinsic_fkt)(ir_type *method, const ir_op *op,
+ const ir_mode *imode,
+ const ir_mode *omode, void *context);
+
+/**
+ * The lowering parameter description.
+ */
+typedef struct lwrdw_param_t {
+ unsigned little_endian : 1; /**< if true should be lowered for little endian, else big endian */
+ unsigned doubleword_size; /**< bitsize of the doubleword mode */
+ create_intrinsic_fkt *create_intrinsic; /**< callback that creates the intrinsic entity */
+ void *ctx; /**< context parameter for the creator function */
+} lwrdw_param_t;
+
+/**
+ * Prepare the doubleword lowering algorithm. Creates an environment
+ * which can be used to register custom lowering functions
+ */
+void ir_prepare_dw_lowering(const lwrdw_param_t *param);
+
+/**
+ * Lower all doubleword operations in the program.
+ * Must be called after ir_prepare_dw_lowering()
+ */
+void ir_lower_dw_ops(void);
+
+typedef void (*lower_dw_func)(ir_node *node, ir_mode *mode);
+
+/**
+ * register a custom lowering function.
+ * After lowering the custom function should call ir_set_dw_lowered()
+ */
+void ir_register_dw_lower_function(ir_op *op, lower_dw_func func);
+
+/**
+ * After lowering a node a custom doubleword lowering function has to call this.
+ * It registers 2 new values for the high and low part of the lowered value.
+ */
+void ir_set_dw_lowered(ir_node *old, ir_node *new_low,
+ ir_node *new_high);
+
+/**
+ * Query lowering results of a node. In a lowering callback you can use this
+ * on all predecessors of a node. The only exception are block and phi nodes.
+ * Their predecessors are not necessarily transformed yet.
+ */
+lower64_entry_t *get_node_entry(ir_node *node);
+
+static inline ir_node *get_lowered_low(ir_node *node)
+{
+ return get_node_entry(node)->low_word;
+}
+
+static inline ir_node *get_lowered_high(ir_node *node)
+{
+ return get_node_entry(node)->high_word;
+}
+
+/**
+ * Default implementation. Context is unused.
+ */
+ir_entity *def_create_intrinsic_fkt(ir_type *method, const ir_op *op,
+ const ir_mode *imode, const ir_mode *omode,
+ void *context);
+
+#endif