/*
- * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
+ * Copyright (C) 1995-2011 University of Karlsruhe. All right reserved.
*
* This file is part of libFirm.
*
/**
* @file
- * @brief lowers operations with mode_b. The result is a graph which
- * might still contains some convs from/to mode_b, but no
- * operations are performed on them anymore, they are just there
- * so modes match. A backend can safely skip all mode_b convs.
+ * @brief lower mode_b operations to something the backend can handle
* @author Matthias Braun, Christoph Mallon
* @version $Id$
- *
- * After this pass the following should hold:
- * - The only inputs with mode_b are for the Cond node or the
- * Sel input of a Mux node.
- * - The only nodes producing mode_b are: Proj(Cmp) and ConvB(X) (where X
- * is some mode that can be converted to the lowered mode).
- * ConvB will usually be implemented by a comparison with 0 producing some
- * flags in the backends. It's debatable wether ConvB(X) is a goode idea.
- * Maybe we should rather introduce a Test node.
- * All other former uses should be converted to manipulations with an integer
- * mode that was specified in the pass configuration.
*/
#include "config.h"
+#include "lower_mode_b.h"
+
#include <stdlib.h>
#include <stdbool.h>
#include "util.h"
#include "array.h"
-static const lower_mode_b_config_t *config;
-static ir_type *lowered_type;
-static ir_node **lowered_nodes;
-static ir_node **check_later;
+typedef struct needs_lowering_t {
+ ir_node *node;
+ int input;
+} needs_lowering_t;
-/**
- * Removes a node if its out-edge count has reached 0.
- * temporary hack until we have proper automatic dead code elimination.
- */
-static void maybe_kill_node(ir_node *node)
-{
- ir_graph *irg;
- int i, arity;
-
- if (get_irn_n_edges(node) != 0)
- return;
-
- irg = get_irn_irg(node);
-
- assert(!is_Bad(node));
-
- arity = get_irn_arity(node);
- for (i = 0; i < arity; ++i) {
- set_irn_n(node, i, new_r_Bad(irg));
- }
- set_nodes_block(node, new_r_Bad(irg));
-
- edges_node_deleted(node, irg);
-}
+static const lower_mode_b_config_t *config;
+static needs_lowering_t *needs_lowering;
static ir_node *create_not(dbg_info *dbgi, ir_node *node)
{
return new_rd_Eor(dbgi, block, node, one, mode);
}
-static ir_node *create_convb(ir_node *node)
+static ir_node *convert_to_modeb(ir_node *node)
{
- ir_node *block = get_nodes_block(node);
- ir_node *conv = new_rd_Conv(NULL, block, node, mode_b);
-
- return conv;
-}
-
-static ir_type *create_lowered_type(void)
-{
- if (lowered_type == NULL) {
- lowered_type = new_type_primitive(config->lowered_mode);
- }
- return lowered_type;
-}
-
-ir_node *ir_create_mux_set(ir_node *cond, ir_mode *dest_mode)
-{
- ir_graph *irg = get_irn_irg(cond);
- ir_node *block = get_nodes_block(cond);
- ir_tarval *tv_one = get_mode_one(dest_mode);
- ir_node *one = new_r_Const(irg, tv_one);
- ir_tarval *tv_zero = get_mode_null(dest_mode);
+ ir_node *block = get_nodes_block(node);
+ ir_graph *irg = get_irn_irg(node);
+ ir_mode *mode = config->lowered_mode;
+ ir_tarval *tv_zero = get_mode_null(mode);
ir_node *zero = new_r_Const(irg, tv_zero);
- ir_node *set = new_r_Mux(block, cond, zero, one, dest_mode);
- return set;
+ ir_node *cmp = new_r_Cmp(block, node, zero, ir_relation_less_greater);
+ return cmp;
}
ir_node *ir_create_cond_set(ir_node *cond_value, ir_mode *dest_mode)
set_irn_in(lower_block, ARRAY_SIZE(lower_in), lower_in);
phi = new_r_Phi(lower_block, ARRAY_SIZE(phi_in), phi_in, dest_mode);
- /* make sure we do visit the cond_value later... */
- ARR_APP1(ir_node*, check_later, cond_value);
-
return phi;
}
-static void adjust_method_type(ir_type *method_type)
-{
- int i;
- int n_params;
- int n_res;
-
- n_params = get_method_n_params(method_type);
- for (i = 0; i < n_params; ++i) {
- ir_type *param = get_method_param_type(method_type, i);
- if (get_type_mode(param) == mode_b) {
- set_method_param_type(method_type, i, create_lowered_type());
- }
- }
-
- n_res = get_method_n_ress(method_type);
- for (i = 0; i < n_res; ++i) {
- ir_type *res_type = get_method_res_type(method_type, i);
- if (get_type_mode(res_type) == mode_b) {
- set_method_res_type(method_type, i, create_lowered_type());
- }
- }
-}
-
static ir_node *lower_node(ir_node *node)
{
dbg_info *dbgi = get_irn_dbg_info(node);
ir_node *block = get_nodes_block(node);
ir_mode *mode = config->lowered_mode;
+ ir_node *res = (ir_node*)get_irn_link(node);
ir_graph *irg;
- ir_node *res;
- res = get_irn_link(node);
if (res != NULL)
return res;
+ node = skip_Tuple(node);
+
assert(get_irn_mode(node) == mode_b);
irg = get_irn_irg(node);
* nodes and this Phi might have them (indirectly) as operands, so they
* would be replaced twice. */
set_irn_link(node, new_phi);
- ARR_APP1(ir_node*, lowered_nodes, node);
for (i = 0; i < arity; ++i) {
- ir_node *in = get_irn_n(node, i);
- ir_node *low_in = lower_node(in);
+ ir_node *in = get_irn_n(node, i);
+ ir_node *lowered_in = lower_node(in);
- set_irn_n(new_phi, i, low_in);
+ set_irn_n(new_phi, i, lowered_in);
}
return new_phi;
break;
}
- case iro_Conv: {
- ir_node *pred = get_Conv_op(node);
- ir_mode *mode = get_irn_mode(pred);
- ir_tarval *tv_zeroc = get_mode_null(mode);
- ir_node *zero_cmp = new_rd_Const(dbgi, irg, tv_zeroc);
+ case iro_Cmp: {
+ ir_node *left = get_Cmp_left(node);
+ ir_node *right = get_Cmp_right(node);
+ ir_mode *cmp_mode = get_irn_mode(left);
+ ir_relation relation = get_Cmp_relation(node);
+
+ if ((mode_is_int(cmp_mode) || mode_is_reference(cmp_mode)) &&
+ (get_mode_size_bits(cmp_mode) < get_mode_size_bits(mode) ||
+ (mode_is_signed(cmp_mode) && is_Const(right) && is_Const_null(right) && relation != ir_relation_greater))) {
+ int need_not = 0;
+ ir_node *a = NULL;
+ ir_node *b = NULL;
+ int bits;
+ ir_tarval *tv;
+ ir_node *shift_cnt;
+
+ if (relation == ir_relation_less) {
+ /* a < b -> (a - b) >> 31 */
+ a = left;
+ b = right;
+ } else if (relation == ir_relation_less_equal) {
+ /* a <= b -> ~(a - b) >> 31 */
+ a = right;
+ b = left;
+ need_not = 1;
+ } else if (relation == ir_relation_greater) {
+ /* a > b -> (b - a) >> 31 */
+ a = right;
+ b = left;
+ } else if (relation == ir_relation_greater_equal) {
+ /* a >= b -> ~(a - b) >> 31 */
+ a = left;
+ b = right;
+ need_not = 1;
+ } else {
+ goto synth_zero_one;
+ }
- ir_node *cmp = new_rd_Cmp(dbgi, block, pred, zero_cmp);
- ir_node *proj = new_rd_Proj(dbgi, cmp, mode_b, pn_Cmp_Lg);
- res = config->create_set(proj);
- break;
- }
+ bits = get_mode_size_bits(mode);
+ tv = new_tarval_from_long(bits-1, mode_Iu);
+ shift_cnt = new_rd_Const(dbgi, irg, tv);
- case iro_Proj: {
- ir_node *pred = get_Proj_pred(node);
-
- if (is_Cmp(pred)) {
- ir_node *left = get_Cmp_left(pred);
- ir_node *right = get_Cmp_right(pred);
- ir_mode *cmp_mode = get_irn_mode(left);
-
- if ((mode_is_int(cmp_mode) || mode_is_reference(cmp_mode)) &&
- (get_mode_size_bits(cmp_mode) < get_mode_size_bits(mode) ||
- (mode_is_signed(cmp_mode) && is_Const(right) && is_Const_null(right)))) {
- int pnc = get_Proj_proj(node);
- int need_not = 0;
- ir_node *a = NULL;
- ir_node *b = NULL;
- int bits;
- ir_tarval *tv;
- ir_node *shift_cnt;
-
- if (pnc == pn_Cmp_Lt) {
- /* a < b -> (a - b) >> 31 */
- a = left;
- b = right;
- } else if (pnc == pn_Cmp_Le) {
- /* a <= b -> ~(a - b) >> 31 */
- a = right;
- b = left;
- need_not = 1;
- } else if (pnc == pn_Cmp_Gt) {
- /* a > b -> (b - a) >> 31 */
- a = right;
- b = left;
- } else if (pnc == pn_Cmp_Ge) {
- /* a >= b -> ~(a - b) >> 31 */
- a = left;
- b = right;
- need_not = 1;
- } else {
- goto synth_zero_one;
- }
-
- bits = get_mode_size_bits(mode);
- tv = new_tarval_from_long(bits-1, mode_Iu);
- shift_cnt = new_rd_Const(dbgi, irg, tv);
-
- if (cmp_mode != mode) {
- a = new_rd_Conv(dbgi, block, a, mode);
- b = new_rd_Conv(dbgi, block, b, mode);
- }
-
- res = new_rd_Sub(dbgi, block, a, b, mode);
- if (need_not) {
- res = new_rd_Not(dbgi, block, res, mode);
- }
- res = new_rd_Shr(dbgi, block, res, shift_cnt, mode);
- } else {
- /* synthesize the 0/1 value */
-synth_zero_one:
- res = config->create_set(node);
+ if (cmp_mode != mode) {
+ a = new_rd_Conv(dbgi, block, a, mode);
+ b = new_rd_Conv(dbgi, block, b, mode);
+ }
+
+ res = new_rd_Sub(dbgi, block, a, b, mode);
+ if (need_not) {
+ res = new_rd_Not(dbgi, block, res, mode);
}
- } else if (is_Proj(pred) && is_Call(get_Proj_pred(pred))) {
- ir_type *type = get_Call_type(get_Proj_pred(pred));
- adjust_method_type(type);
- set_irn_mode(node, mode);
- res = node;
- goto own_replacement;
- } else if (is_Proj(pred) && is_Start(get_Proj_pred(pred))) {
- ir_graph *irg = get_irn_irg(node);
- ir_entity *entity = get_irg_entity(irg);
- ir_type *type = get_entity_type(entity);
- adjust_method_type(type);
- set_irn_mode(node, mode);
- res = node;
- goto own_replacement;
+ res = new_rd_Shr(dbgi, block, res, shift_cnt, mode);
} else {
- panic("unexpected projb: %+F (pred: %+F)", node, pred);
+ /* synthesize the 0/1 value */
+synth_zero_one:
+ res = config->create_set(node);
}
break;
}
res = new_r_Unknown(irg, mode);
break;
+ case iro_Bad:
+ res = new_r_Bad(irg, mode);
+ break;
+
default:
- panic("didn't expect %+F to have mode_b", node);
+ panic("Don't know how to lower mode_b node %+F", node);
}
- ARR_APP1(ir_node*, lowered_nodes, node);
-own_replacement:
set_irn_link(node, res);
return res;
}
-static void lower_mode_b_walker(ir_node *node, void *env)
+static bool needs_mode_b_input(const ir_node *node, int input)
+{
+ return (is_Cond(node) && input == n_Cond_selector)
+ || (is_Mux(node) && input == n_Mux_sel);
+}
+
+/**
+ * Collects "roots" of a mode_b calculation. These are nodes which require a
+ * mode_b input (Cond, Mux, Conv(xxx_b))
+ */
+static void collect_needs_lowering(ir_node *node, void *env)
{
- int i, arity;
- bool changed = false;
+ int arity = get_irn_arity(node);
+ int i;
+ (void) env;
+
+ /* if the node produces mode_b then it is a not a root (but should be
+ * something our lower_node function can handle) */
+ if (get_irn_mode(node) == mode_b) {
+ assert(is_And(node) || is_Or(node) || is_Eor(node) || is_Phi(node)
+ || is_Not(node) || is_Mux(node) || is_Cmp(node)
+ || is_Const(node) || is_Unknown(node) || is_Bad(node));
+ return;
+ }
- arity = get_irn_arity(node);
for (i = 0; i < arity; ++i) {
- ir_node *lowered_in;
+ needs_lowering_t entry;
ir_node *in = get_irn_n(node, i);
if (get_irn_mode(in) != mode_b)
continue;
+ if (is_Cmp(in) && needs_mode_b_input(node, i))
+ continue;
- if (! config->lower_direct_cmp) {
- /* Proj(Cmp) as input for Cond and Mux nodes needs no changes.
- (Mux with mode_b is an exception as it gets replaced by and/or
- anyway so we still lower the inputs then) */
- if (is_Cond(node) ||
- (is_Mux(node) && get_irn_mode(node) != mode_b)) {
- if (is_Proj(in)) {
- ir_node *pred = get_Proj_pred(in);
- if (is_Cmp(pred))
- continue;
- }
- }
- }
-
- lowered_in = lower_node(in);
-
- if (is_Call(node)) {
- ir_type *type = get_Call_type(node);
- adjust_method_type(type);
- } else if (is_Cond(node) || (is_Mux(node) && i == 0)) {
- lowered_in = create_convb(lowered_in);
- }
- set_irn_n(node, i, lowered_in);
- changed = true;
- }
- if (changed) {
- bool *global_changed = env;
- *global_changed = true;
- add_identities(node);
+ entry.node = node;
+ entry.input = i;
+ ARR_APP1(needs_lowering_t, needs_lowering, entry);
}
}
void ir_lower_mode_b(ir_graph *irg, const lower_mode_b_config_t *nconfig)
{
- ir_entity *entity = get_irg_entity(irg);
- ir_type *type = get_entity_type(entity);
- bool changed = false;
- int i;
- int n;
+ size_t i;
+ size_t n;
- config = nconfig;
- lowered_nodes = NEW_ARR_F(ir_node*, 0);
- check_later = NEW_ARR_F(ir_node*, 0);
- lowered_type = NULL;
+ config = nconfig;
+ /* edges are used by part_block_edges in the ir_create_cond_set variant. */
edges_assure(irg);
- /* ensure no optimisation touches muxes anymore */
- set_irg_state(irg, IR_GRAPH_STATE_KEEP_MUX | IR_GRAPH_STATE_BCONV_ALLOWED);
-
+ set_irg_state(irg, IR_GRAPH_STATE_MODEB_LOWERED);
ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
- adjust_method_type(type);
-
- irg_walk_graph(irg, firm_clear_link, NULL, NULL);
- irg_walk_graph(irg, lower_mode_b_walker, NULL, &changed);
+ needs_lowering = NEW_ARR_F(needs_lowering_t, 0);
- for (i = 0; i < ARR_LEN(check_later); ++i) {
- ir_node *node = check_later[i];
- irg_walk_core(node, lower_mode_b_walker, NULL, &changed);
- }
+ irg_walk_graph(irg, firm_clear_link, collect_needs_lowering, NULL);
- n = ARR_LEN(lowered_nodes);
+ n = ARR_LEN(needs_lowering);
for (i = 0; i < n; ++i) {
- ir_node *node = lowered_nodes[i];
- maybe_kill_node(node);
+ const needs_lowering_t *entry = &needs_lowering[i];
+ ir_node *node = entry->node;
+ int input = entry->input;
+ ir_node *in = get_irn_n(node, input);
+ ir_node *lowered = lower_node(in);
+
+ if (needs_mode_b_input(node, input))
+ lowered = convert_to_modeb(lowered);
+ set_irn_n(node, input, lowered);
}
- DEL_ARR_F(check_later);
- DEL_ARR_F(lowered_nodes);
ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
- if (changed) {
- set_irg_outs_inconsistent(irg);
+ DEL_ARR_F(needs_lowering);
+
+ if (n > 0) {
+ /* lowering might create new blocks, so be sure to handle this */
+ set_irg_extblk_inconsistent(irg);
+ clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE);
+ edges_deactivate(irg);
}
}
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