+/**
+ * A mapper for mapping f(0.0) to 0.0.
+ */
+static int i_mapper_zero_to_zero(ir_node *call, void *ctx, int reason) {
+ ir_node *val = get_Call_param(call, 0);
+ (void) ctx;
+
+ if (is_Const(val) && is_Const_null(val)) {
+ /* f(0.0) = 0.0 */
+ ir_node *mem = get_Call_mem(call);
+ DBG_OPT_ALGSIM0(call, val, reason);
+ replace_call(val, call, mem, NULL, NULL);
+ return 1;
+ }
+ return 0;
+} /* i_mapper_zero_to_zero */
+
+/**
+ * A mapper for mapping f(1.0) to 0.0.
+ */
+static int i_mapper_one_to_zero(ir_node *call, void *ctx, int reason) {
+ ir_node *val = get_Call_param(call, 0);
+ (void) ctx;
+
+ if (is_Const(val) && is_Const_one(val)) {
+ /* acos(1.0) = 0.0 */
+ ir_node *block = get_nodes_block(call);
+ ir_mode *mode = get_irn_mode(val);
+ ir_node *irn = new_r_Const(current_ir_graph, block, mode, get_mode_null(mode));
+ ir_node *mem = get_Call_mem(call);
+ DBG_OPT_ALGSIM0(call, irn, reason);
+ replace_call(irn, call, mem, NULL, NULL);
+ return 1;
+ }
+ return 0;
+} /* i_mapper_one_to_zero */
+
+/**
+ * A mapper for mapping a functions with the following characteristics:
+ * f(-x) = f(x).
+ * f(0.0) = 1.0
+ */
+static int i_mapper_symmetric_zero_to_one(ir_node *call, void *ctx, int reason) {
+ ir_node *val = get_Call_param(call, 0);
+ (void) ctx;
+
+ if (is_strictConv(val)) {
+ ir_node *op = get_Conv_op(val);
+ if (is_Minus(op)) {
+ /* f(-x) = f(x) with strictConv */
+ ir_node *block = get_nodes_block(call);
+ ir_mode *mode = get_irn_mode(val);
+ dbg_info *dbg = get_irn_dbg_info(val);
+
+ op = get_Minus_op(op);
+ val = new_rd_Conv(dbg, current_ir_graph, block, op, mode);
+ if (is_Conv(val)) {
+ /* still a Conv ? */
+ set_Conv_strict(val, 1);
+ }
+ DBG_OPT_ALGSIM2(call, op, call, FS_OPT_RTS_SYMMETRIC);
+ set_Call_param(call, 0, val);
+ }
+ } else if (is_Minus(val)) {
+ /* f(-x) = f(x) */
+ val = get_Minus_op(val);
+ DBG_OPT_ALGSIM2(call, val, call, FS_OPT_RTS_SYMMETRIC);
+ set_Call_param(call, 0, val);
+ }
+
+ if (is_Const(val) && is_Const_null(val)) {
+ /* f(0.0) = 1.0 */
+ ir_node *block = get_nodes_block(call);
+ ir_mode *mode = get_irn_mode(val);
+ ir_node *irn = new_r_Const(current_ir_graph, block, mode, get_mode_one(mode));
+ ir_node *mem = get_Call_mem(call);
+ DBG_OPT_ALGSIM0(call, irn, reason);
+ replace_call(irn, call, mem, NULL, NULL);
+ return 1;
+ }
+ return 0;
+} /* i_mapper_symmetric_zero_to_one */
+
+/* A mapper for the floating point log. */
+int i_mapper_log(ir_node *call, void *ctx) {
+ /* log(1.0) = 0.0 */
+ return i_mapper_one_to_zero(call, ctx, FS_OPT_RTS_LOG);
+} /* i_mapper_log */
+
+/* A mapper for the floating point sin. */
+int i_mapper_sin(ir_node *call, void *ctx) {
+ /* sin(0.0) = 0.0 */
+ return i_mapper_zero_to_zero(call, ctx, FS_OPT_RTS_SIN);
+} /* i_mapper_sin */
+
+/* A mapper for the floating point cos. */
+int i_mapper_cos(ir_node *call, void *ctx) {
+ /* cos(0.0) = 1.0, cos(-x) = x */
+ return i_mapper_symmetric_zero_to_one(call, ctx, FS_OPT_RTS_COS);
+} /* i_mapper_cos */
+
+/* A mapper for the floating point tan. */
+int i_mapper_tan(ir_node *call, void *ctx) {
+ /* tan(0.0) = 0.0 */
+ return i_mapper_zero_to_zero(call, ctx, FS_OPT_RTS_TAN);
+} /* i_mapper_tan */
+
+/* A mapper for the floating point asin. */
+int i_mapper_asin(ir_node *call, void *ctx) {
+ /* asin(0.0) = 0.0 */
+ return i_mapper_zero_to_zero(call, ctx, FS_OPT_RTS_ASIN);
+} /* i_mapper_asin */
+
+/* A mapper for the floating point acos. */
+int i_mapper_acos(ir_node *call, void *ctx) {
+ /* acos(1.0) = 0.0 */
+ return i_mapper_one_to_zero(call, ctx, FS_OPT_RTS_ACOS);
+} /* i_mapper_acos */
+
+/* A mapper for the floating point atan. */
+int i_mapper_atan(ir_node *call, void *ctx) {
+ /* atan(0.0) = 0.0 */
+ return i_mapper_zero_to_zero(call, ctx, FS_OPT_RTS_ATAN);
+} /* i_mapper_atan */
+
+/* A mapper for the floating point sinh. */
+int i_mapper_sinh(ir_node *call, void *ctx) {
+ /* sinh(0.0) = 0.0 */
+ return i_mapper_zero_to_zero(call, ctx, FS_OPT_RTS_SINH);
+} /* i_mapper_sinh */
+
+/* A mapper for the floating point cosh. */
+int i_mapper_cosh(ir_node *call, void *ctx) {
+ /* cosh(0.0) = 1.0, cosh(-x) = x */
+ return i_mapper_symmetric_zero_to_one(call, ctx, FS_OPT_RTS_COSH);
+} /* i_mapper_cosh */
+
+/* A mapper for the floating point tanh. */
+int i_mapper_tanh(ir_node *call, void *ctx) {
+ /* tanh(0.0) = 0.0 */
+ return i_mapper_zero_to_zero(call, ctx, FS_OPT_RTS_TANH);
+} /* i_mapper_tanh */
+
+/**
+ * Return the const entity that is accessed through the pointer ptr or
+ * NULL if there is no entity (or the entity is not constant).
+ *
+ * @param ptr the pointer
+ */
+static ir_entity *get_const_entity(ir_node *ptr) {
+ /* FIXME: this cannot handle constant strings inside struct initializers yet */
+ if (is_Global(ptr)) {
+ ir_entity *ent = get_Global_entity(ptr);
+
+ if (get_entity_variability(ent) == variability_constant) {
+ /* a constant entity */
+ return ent;
+ }
+ }
+ return NULL;
+} /* get_const_entity */
+
+/**
+ * Calculate the value of strlen if possible.
+ *
+ * @param ent the entity
+ * @param res_tp the result type
+ *
+ * @return a Const node containing the strlen() result or NULL
+ * if the evaluation fails
+ */
+static ir_node *eval_strlen(ir_entity *ent, ir_type *res_tp) {
+ ir_type *tp = get_entity_type(ent);
+ ir_mode *mode;
+ int i, n, len = -1;
+
+ if (! is_Array_type(tp))
+ return NULL;
+ tp = get_array_element_type(tp);
+ if (! is_Primitive_type(tp))
+ return NULL;
+ mode = get_type_mode(tp);
+
+ /* FIXME: This is too restrict, as the type char might be more the 8bits */
+ if (!mode_is_int(mode) || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
+ return NULL;
+
+ n = get_compound_ent_n_values(ent);
+ for (i = 0; i < n; ++i) {
+ ir_node *irn = get_compound_ent_value(ent, i);
+
+ if (! is_Const(irn))
+ return NULL;
+
+ if (is_Const_null(irn)) {
+ /* found the length */
+ len = i;
+ break;
+ }
+ }
+ if (len >= 0) {
+ tarval *tv = new_tarval_from_long(len, get_type_mode(res_tp));
+ return new_Const_type(tv, res_tp);
+ }
+ return NULL;
+} /* eval_strlen */
+
+/* A mapper for strlen */
+int i_mapper_strlen(ir_node *call, void *ctx) {
+ ir_node *s = get_Call_param(call, 0);
+ ir_entity *ent = get_const_entity(s);
+
+ (void) ctx;
+
+ /* FIXME: this cannot handle constant strings inside struct initializers yet */
+ if (ent != NULL) {
+ /* a constant entity */
+ ir_type *tp = get_Call_type(call);
+ ir_node *irn;
+
+ tp = get_method_res_type(tp, 0);
+ irn = eval_strlen(ent, tp);
+
+ if (irn) {
+ ir_node *mem = get_Call_mem(call);
+ DBG_OPT_ALGSIM0(call, irn, FS_OPT_RTS_STRLEN);
+ replace_call(irn, call, mem, NULL, NULL);
+ return 1;
+ }
+ }
+ return 0;
+} /* i_mapper_strlen */
+
+/**
+ * Calculate the value of strlen if possible.
+ *
+ * @param left the left entity
+ * @param right the right entity
+ * @param res_tp the result type
+ *
+ * @return a Const node containing the strcmp() result or NULL
+ * if the evaluation fails
+ */
+static ir_node *eval_strcmp(ir_entity *left, ir_entity *right, ir_type *res_tp) {
+ ir_type *tp;
+ ir_mode *mode;
+ int i, n, n_r, res;
+
+ tp = get_entity_type(left);
+ if (! is_Array_type(tp))
+ return NULL;
+ tp = get_array_element_type(tp);
+ if (! is_Primitive_type(tp))
+ return NULL;
+ mode = get_type_mode(tp);
+
+ /* FIXME: This is too restrict, as the type char might be more the 8bits */
+ if (!mode_is_int(mode) || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
+ return NULL;
+
+ tp = get_entity_type(right);
+ if (! is_Array_type(tp))
+ return NULL;
+ tp = get_array_element_type(tp);
+ if (! is_Primitive_type(tp))
+ return NULL;
+ mode = get_type_mode(tp);
+
+ /* FIXME: This is too restrict, as the type char might be more the 8bits */
+ if (!mode_is_int(mode) || get_mode_size_bits(mode) != get_mode_size_bits(mode_Bs))
+ return NULL;
+
+ n = get_compound_ent_n_values(left);
+ n_r = get_compound_ent_n_values(right);
+ if (n_r < n)
+ n = n_r;
+ for (i = 0; i < n; ++i) {
+ ir_node *irn;
+ long v_l, v_r;
+ tarval *tv;
+
+ irn = get_compound_ent_value(left, i);
+ if (! is_Const(irn))
+ return NULL;
+ tv = get_Const_tarval(irn);
+ v_l = get_tarval_long(tv);
+
+ irn = get_compound_ent_value(right, i);
+ if (! is_Const(irn))
+ return NULL;
+ tv = get_Const_tarval(irn);
+ v_r = get_tarval_long(tv);
+
+ if (v_l < v_r) {
+ res = -1;
+ break;
+ }
+ if (v_l > v_r) {
+ res = +1;
+ break;
+ }
+
+ if (v_l == 0) {
+ res = 0;
+ break;
+ }
+ }
+ if (i < n) {
+ /* we found an end */
+ tarval *tv = new_tarval_from_long(res, get_type_mode(res_tp));
+ return new_Const_type(tv, res_tp);
+ }
+ return NULL;
+} /* eval_strcmp */
+
+/**
+ * Checks if an entity represents the empty string.
+ *
+ * @param ent the entity
+ *
+ * @return non-zero if ent represents the empty string
+ */
+static int is_empty_string(ir_entity *ent) {
+ ir_type *tp = get_entity_type(ent);
+ ir_mode *mode;
+ int n;