* @param mtp the method type to lower
*
* The current implementation expects that a lowered type already
- * includes the necessery changes ...
+ * includes the necessary changes ...
*/
static ir_type *create_modified_mtd_type(const lower_params_t *lp, ir_type *mtp)
{
- ir_type *lowered;
+ ir_type *lowered, *ptr_tp;
ir_type **params, **results, *res_tp;
+ ir_mode *modes[MAX_REGISTER_RET_VAL];
int n_ress, n_params, nn_ress, nn_params, i, first_variadic;
ident *id;
add_hidden hidden_params;
for (nn_ress = nn_params = i = 0; i < n_ress; ++i) {
res_tp = get_method_res_type(mtp, i);
- if (is_compound_type(res_tp))
- params[nn_params++] = lp->find_pointer_type(res_tp, get_modeP_data(), lp->def_ptr_alignment);
+ if (is_compound_type(res_tp)) {
+ int n_regs = 0;
+
+ if (lp->flags & LF_SMALL_CMP_IN_REGS)
+ n_regs = lp->ret_compound_in_regs(res_tp, modes);
+
+ if (n_regs > 0) {
+ /* this compound will be returned solely in registers */
+ assert(0);
+ }
+ else {
+ /* this compound will be allocated on callers stack and its
+ address will be transmitted as a hidden parameter. */
+ ptr_tp = lp->find_pointer_type(res_tp, get_modeP_data(), lp->def_ptr_alignment);
+ params[nn_params++] = ptr_tp;
+ if (lp->flags & LF_RETURN_HIDDEN)
+ results[nn_ress++] = ptr_tp;
+ }
+ }
else
results[nn_ress++] = res_tp;
}
* Walker environment for fix_args_and_collect_calls().
*/
typedef struct _wlk_env_t {
- int arg_shift; /**< The Argument index shift for parameters. */
- int first_hidden; /**< The index of the first hidden argument. */
- struct obstack obst; /**< An obstack to allocate the data on. */
- cl_entry *cl_list; /**< The call list. */
- pmap *dummy_map; /**< A map for finding the dummy arguments. */
- unsigned dnr; /**< The dummy index number. */
+ int arg_shift; /**< The Argument index shift for parameters. */
+ int first_hidden; /**< The index of the first hidden argument. */
+ struct obstack obst; /**< An obstack to allocate the data on. */
+ cl_entry *cl_list; /**< The call list. */
+ pmap *dummy_map; /**< A map for finding the dummy arguments. */
+ unsigned dnr; /**< The dummy index number. */
+ const lower_params_t *params; /**< lowering parameters */
} wlk_env;
/**
}
else if (op == op_Call) {
ctp = get_Call_type(n);
- for (i = get_method_n_ress(ctp) -1; i >= 0; --i) {
- if (is_compound_type(get_method_res_type(ctp, i))) {
- /*
- * This is a call with a compound return. As the result
- * might be ignored, we must put it in the list.
- */
- (void)get_Call_entry(n, env);
+ if (env->params->flags & LF_COMPOUND_RETURN) {
+ /* check for compound returns */
+ for (i = get_method_n_ress(ctp) -1; i >= 0; --i) {
+ if (is_compound_type(get_method_res_type(ctp, i))) {
+ /*
+ * This is a call with a compound return. As the result
+ * might be ignored, we must put it in the list.
+ */
+ (void)get_Call_entry(n, env);
+ }
}
}
}
- else if (op == op_CopyB) {
+ else if (op == op_CopyB && env->params->flags & LF_COMPOUND_RETURN) {
+ /* check for compound returns */
ir_node *src = get_CopyB_src(n);
/* older scheme using value_res_ent */
if (is_Sel(src)) {
/**
* Fix all calls on a call list by adding hidden parameters.
*
- * @param lp the parameter struct
* @param irg the graph
* @param env the environment
*/
-static void fix_call_list(const lower_params_t *lp, ir_graph *irg, wlk_env *env) {
+static void fix_call_list(ir_graph *irg, wlk_env *env) {
+ const lower_params_t *lp = env->params;
cl_entry *p;
ir_node *call, **new_in;
ir_type *ctp, *lowered_mtp;
add_hidden hidden_params;
int i, n_params, n_com, pos;
- unsigned dnr = 0;
new_in = NEW_ARR_F(ir_node *, 0);
for (p = env->cl_list; p; p = p->next) {
{
entity *ent = get_irg_entity(irg);
ir_type *mtp, *lowered_mtp, *res_tp, *ft;
- int i, j, k, n_ress, n_com, n_cr_opt;
+ int i, j, k, n_ress, n_ret_com, n_cr_opt;
ir_node **new_in, *ret, *endbl, *bl, *mem, *copy;
cr_pair *cr_opt;
wlk_env env;
assert(get_irg_phase_state(irg) == phase_high && "call lowering must be done in phase high");
mtp = get_entity_type(ent);
- n_ress = get_method_n_ress(mtp);
- for (n_com = i = 0; i < n_ress; ++i) {
- res_tp = get_method_res_type(mtp, i);
- if (is_compound_type(res_tp))
- ++n_com;
+ if (lp->flags & LF_COMPOUND_RETURN) {
+ /* calculate the number of compound returns */
+ n_ress = get_method_n_ress(mtp);
+ for (n_ret_com = i = 0; i < n_ress; ++i) {
+ res_tp = get_method_res_type(mtp, i);
+
+ if (is_compound_type(res_tp))
+ ++n_ret_com;
+ }
}
- if (n_com) {
+ if (n_ret_com) {
/* much easier if we have only one return */
normalize_one_return(irg);
if (hidden_params == ADD_HIDDEN_ALWAYS_IN_FRONT) {
/* hidden arguments are added first */
- env.arg_shift = n_com;
+ env.arg_shift = n_ret_com;
env.first_hidden = 0;
}
else {
env.cl_list = NULL;
env.dummy_map = pmap_create_ex(8);
env.dnr = 0;
+ env.params = lp;
/* scan the code, fix argument numbers and collect calls. */
irg_walk_graph(irg, firm_clear_link, fix_args_and_collect_calls, &env);
/* fix all calls */
if (env.cl_list)
- fix_call_list(lp, irg, &env);
+ fix_call_list(irg, &env);
- if (n_com) {
+ if (n_ret_com) {
/*
* Now fix the Return node of the current graph.
*/
* STEP 2: fix it. For all compound return values add a CopyB,
* all others are copied.
*/
- NEW_ARR_A(ir_node *, new_in, n_ress - n_com + 1);
+ NEW_ARR_A(ir_node *, new_in, n_ress + 1);
bl = get_nodes_block(ret);
mem = get_Return_mem(ret);
ft = get_irg_frame_type(irg);
- NEW_ARR_A(cr_pair, cr_opt, n_com);
+ NEW_ARR_A(cr_pair, cr_opt, n_ret_com);
n_cr_opt = 0;
for (j = 1, i = k = 0; i < n_ress; ++i) {
ir_node *pred = get_Return_res(ret, i);
);
mem = new_r_Proj(irg, bl, copy, mode_M, pn_CopyB_M_regular);
}
+ if (lp->flags & LF_RETURN_HIDDEN) {
+ new_in[j] = arg;
+ ++j;
+ }
}
- else { /* skalar return value */
+ else { /* scalar return value */
new_in[j] = pred;
++j;
}
}
+ /* replace the in of the Return */
new_in[0] = mem;
set_irn_in(ret, j, new_in);
remove_class_member(ft, cr_opt[i].ent);
}
}
- } /* n_com */
+ } /* if (n_ret_com) */
pmap_destroy(env.dummy_map);
obstack_free(&env.obst, NULL);
* Returns non-zero if the given type is a method
* type that must be lowered.
*
+ * @param lp lowering parameters
* @param tp The type.
*/
-static int must_be_lowered(ir_type *tp) {
+static int must_be_lowered(const lower_params_t *lp, ir_type *tp) {
int i, n_ress;
ir_type *res_tp;
if (is_Method_type(tp)) {
- n_ress = get_method_n_ress(tp);
- for (i = 0; i < n_ress; ++i) {
- res_tp = get_method_res_type(tp, i);
-
- if (is_compound_type(res_tp))
- return 1;
+ if (lp->flags & LF_COMPOUND_RETURN) {
+ /* check for compound returns */
+ n_ress = get_method_n_ress(tp);
+ for (i = 0; i < n_ress; ++i) {
+ res_tp = get_method_res_type(tp, i);
+
+ if (is_compound_type(res_tp))
+ return 1;
+ }
}
}
return 0;
entity *ent = (entity *)tore;
tp = get_entity_type(ent);
- if (must_be_lowered(tp)) {
+ if (must_be_lowered(lp, tp)) {
tp = create_modified_mtd_type(lp, tp);
set_entity_type(ent, tp);
}
/* fix pointer to methods */
if (is_Pointer_type(tp)) {
ir_type *etp = get_pointer_points_to_type(tp);
- if (must_be_lowered(etp)) {
+ if (must_be_lowered(lp, etp)) {
etp = create_modified_mtd_type(lp, etp);
set_pointer_points_to_type(tp, etp);
}
}
/*
- * Lower calls with compound return types.
+ * Lower calls with compound parameters and return types.
* This function does the following transformations:
*
* - Adds a new (hidden) pointer parameter for
*
* - Replace a possible block copy after the function call.
*/
-void lower_compound_ret_calls(const lower_params_t *params)
+void lower_calls_with_compounds(const lower_params_t *params)
{
int i;
ir_graph *irg;
ADD_HIDDEN_SMART = 2, /**< add hidden parameters last for non-variadic and first for variadic functions. */
} add_hidden;
+/**
+ * Additional flags for the lowering.
+ */
+enum lowering_flags {
+ LF_NONE = 0, /**< no additional flags */
+ LF_COMPOUND_PARAM = 1, /**< lower calls with compound parameters */
+ LF_COMPOUND_RETURN = 2, /**< lower calls with compound returns */
+ LF_RETURN_HIDDEN = 4, /**< return the hidden address instead of void */
+ LF_SMALL_CMP_IN_REGS = 8 /**< return small compound values in registers */
+};
+
+/** Maximum number of registers that can be used to return compound values. */
+#define MAX_REGISTER_RET_VAL 2
+
/**
* A struct containing all control parameters for
* lower_compound_ret_calls().
*/
typedef struct {
int def_ptr_alignment; /**< Default alignment for data pointer. */
+ unsigned flags; /**< A bitmask of enum lowering_flags. */
add_hidden hidden_params; /**< Where to add hidden parameters. */
/**
* If this pointer is NULL, a new pointer type is always created.
*/
ir_type *(*find_pointer_type)(ir_type *e_type, ir_mode *mode, int alignment);
+
+ /**
+ * If the LF_SMALL_CMP_IN_REGS flag is set, this function will be called
+ * to decide, whether a compound value should be returned in registers.
+ * This function must return the number of used registers and fill in the modes
+ * of the registers to use. Up to MAX_REGISTER_RET_VAL registers can be used.
+ */
+ int (*ret_compound_in_regs)(ir_type *compound_tp, ir_mode **modes);
} lower_params_t;
/**
- * Lower calls with compound return types.
+ * Lower calls with compound parameter and return types.
* This function does the following transformations:
*
+ * If LF_COMPOUND_PARAM is set:
+ *
+ * - Copy compound parameters to a new location on the callers
+ * stack and transmit the address of this new location
+ *
+ * If LF_COMPOUND_RETURN is set:
+ *
* - Adds a new (hidden) pointer parameter for
- * any return compound type.
+ * any return compound type. The return type is replaced by void
+ * or if LOWERING_FLAGS_RETURN_HIDDEN is set by the address.
*
* - Use of the hidden parameters in the function code.
*
*
* - Replace a possible block copy after the function call.
*
+ * General:
+ *
* - Changes the types of methods and calls to the lowered ones
*
* - lower all method types of existing entities
* If params->find_pointer_type is NULL, new pointer types
* are always created automatically.
*/
-void lower_compound_ret_calls(const lower_params_t *params);
+void lower_calls_with_compounds(const lower_params_t *params);
#endif /* _LOWER_CALLS_H_ */
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