X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Flower%2Flower_mode_b.c;h=1949be0e8a278d48ec714c9729056b88ff3db4dd;hb=65f2648ba9eb6b3cdd7f0098f7a4e1882fab152a;hp=3df4b9bc0318654a5aa75ee84f62acb8c5bd3f2d;hpb=ca21c59ea00ff05918de26952e91ac39f1589e01;p=libfirm

diff --git a/ir/lower/lower_mode_b.c b/ir/lower/lower_mode_b.c
index 3df4b9bc0..1949be0e8 100644
--- a/ir/lower/lower_mode_b.c
+++ b/ir/lower/lower_mode_b.c
@@ -1,5 +1,5 @@
 /*
- * 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.
  *
@@ -19,26 +19,14 @@
 
 /**
  * @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>
 
@@ -49,169 +37,133 @@
 #include "irtools.h"
 #include "iredges.h"
 #include "iropt_t.h"
+#include "irgmod.h"
 #include "tv.h"
 #include "error.h"
 #include "lowering.h"
 #include "pdeq.h"
 #include "irpass_t.h"
+#include "util.h"
+#include "array.h"
 
-static lower_mode_b_config_t  config;
-static ir_type               *lowered_type  = NULL;
-static pdeq                  *lowered_nodes = NULL;
-
-/**
- * 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_Bad());
-	}
-	set_nodes_block(node, new_Bad());
+typedef struct needs_lowering_t {
+	ir_node *node;
+	int      input;
+} needs_lowering_t;
 
-	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)
 {
-	ir_node  *block  = get_nodes_block(node);
-	ir_mode  *mode   = config.lowered_mode;
-	tarval   *tv_one = get_mode_one(mode);
-	ir_node  *one    = new_d_Const(dbgi, tv_one);
+	ir_node   *block  = get_nodes_block(node);
+	ir_mode   *mode   = config->lowered_mode;
+	ir_tarval *tv_one = get_mode_one(mode);
+	ir_graph  *irg    = get_irn_irg(node);
+	ir_node   *one    = new_rd_Const(dbgi, irg, tv_one);
 
-	return new_rd_Eor(dbgi,	block, node, one, mode);
+	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;
+	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   *cmp     = new_r_Cmp(block, node, zero, ir_relation_less_greater);
+	return cmp;
 }
 
-static ir_type *create_lowered_type(void)
+ir_node *ir_create_cond_set(ir_node *cond_value, ir_mode *dest_mode)
 {
-	if (lowered_type == NULL) {
-		lowered_type = new_type_primitive(config.lowered_mode);
-	}
-	return lowered_type;
-}
-
-/**
- * creates a "set" node that produces a 0 or 1 based on a Cmp result
- */
-static ir_node *create_set(ir_node *node)
-{
-	dbg_info *dbgi    = get_irn_dbg_info(node);
-	ir_mode  *mode    = config.lowered_set_mode;
-	tarval   *tv_one  = get_mode_one(mode);
-	ir_node  *one     = new_d_Const(dbgi, tv_one);
-	ir_node  *block   = get_nodes_block(node);
-	tarval   *tv_zero = get_mode_null(mode);
-	ir_node  *zero    = new_d_Const(dbgi, tv_zero);
-
-	ir_node *set      = new_rd_Mux(dbgi, block, node, zero, one, mode);
-
-	if (mode != config.lowered_mode) {
-		set = new_r_Conv(block, set, config.lowered_mode);
-	}
-
-	return set;
-}
-
-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());
-		}
-	}
+	ir_node  *lower_block = part_block_edges(cond_value);
+	ir_node  *upper_block = get_nodes_block(cond_value);
+	ir_graph *irg         = get_irn_irg(cond_value);
+	ir_node  *cond        = new_r_Cond(upper_block, cond_value);
+	ir_node  *proj_true   = new_r_Proj(cond, mode_X, pn_Cond_true);
+	ir_node  *proj_false  = new_r_Proj(cond, mode_X, pn_Cond_false);
+	ir_node  *in_true[1]  = { proj_true };
+	ir_node  *in_false[1] = { proj_false };
+	ir_node  *true_block  = new_r_Block(irg, ARRAY_SIZE(in_true), in_true);
+	ir_node  *false_block = new_r_Block(irg, ARRAY_SIZE(in_false),in_false);
+	ir_node  *true_jmp    = new_r_Jmp(true_block);
+	ir_node  *false_jmp   = new_r_Jmp(false_block);
+	ir_node  *lower_in[2] = { true_jmp, false_jmp };
+	ir_node  *one         = new_r_Const(irg, get_mode_one(dest_mode));
+	ir_node  *zero        = new_r_Const(irg, get_mode_null(dest_mode));
+	ir_node  *phi_in[2]   = { one, zero };
+	ir_node  *phi;
+
+	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);
+
+	return phi;
 }
 
 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_mode  *mode  = config->lowered_mode;
+	ir_node  *res   = (ir_node*)get_irn_link(node);
+	ir_graph *irg;
 
-	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);
 	switch (get_irn_opcode(node)) {
 	case iro_Phi: {
 		int       i, arity;
 		ir_node **in;
-		ir_node  *unknown, *new_phi;
+		ir_node  *dummy;
+		ir_node  *new_phi;
 
-		arity   = get_irn_arity(node);
-		in      = ALLOCAN(ir_node*, arity);
-		unknown = new_Unknown(mode);
+		arity = get_irn_arity(node);
+		in    = ALLOCAN(ir_node*, arity);
+		dummy = new_r_Dummy(irg, mode);
 		for (i = 0; i < arity; ++i) {
-			in[i] = unknown;
+			in[i] = dummy;
 		}
 		new_phi = new_r_Phi(block, arity, in, mode);
 		/* FIXME This does not correctly break cycles: The Phi might not be the
-		 * first in the recursion, so the caller(s) are some yet un-lowered nodes
-		 * and this Phi might have them (indirectly) as operands, so they would be
-		 * replaced twice. */
+		 * first in the recursion, so the caller(s) are some yet un-lowered
+		 * nodes and this Phi might have them (indirectly) as operands, so they
+		 * would be replaced twice. */
 		set_irn_link(node, new_phi);
-		pdeq_putr(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;
 	}
 
-	case iro_And:
-	case iro_Or:
+	case iro_And: {
+		ir_node *lowered_left  = lower_node(get_And_left(node));
+		ir_node *lowered_right = lower_node(get_And_right(node));
+		res = new_rd_And(dbgi, block, lowered_left, lowered_right, mode);
+		break;
+	}
+	case iro_Or: {
+		ir_node *lowered_left  = lower_node(get_Or_left(node));
+		ir_node *lowered_right = lower_node(get_Or_right(node));
+		res = new_rd_Or(dbgi, block, lowered_left, lowered_right, mode);
+		break;
+	}
 	case iro_Eor: {
-		int i, arity;
-
-		res   = exact_copy(node);
-		arity = get_irn_arity(node);
-		for (i = 0; i < arity; ++i) {
-			ir_node *in     = get_irn_n(node, i);
-			ir_node *low_in = lower_node(in);
-
-			set_irn_n(res, i, low_in);
-		}
-		set_irn_mode(res, mode);
+		ir_node *lowered_left  = lower_node(get_Eor_left(node));
+		ir_node *lowered_right = lower_node(get_Eor_right(node));
+		res = new_rd_Eor(dbgi, block, lowered_left, lowered_right, mode);
 		break;
 	}
 
@@ -238,105 +190,74 @@ static ir_node *lower_node(ir_node *node)
 		break;
 	}
 
-	case iro_Conv: {
-		ir_node *pred     = get_Conv_op(node);
-		ir_mode *mode     = get_irn_mode(pred);
-		tarval  *tv_zeroc = get_mode_null(mode);
-		ir_node *zero_cmp = new_d_Const(dbgi, 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 = 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;
-				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_d_Const(dbgi, 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 = create_set(node);
+			if (cmp_mode != mode) {
+				a = new_rd_Conv(dbgi, block, a, mode);
+				b = new_rd_Conv(dbgi, block, b, 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_entity *entity = get_irg_entity(current_ir_graph);
-			ir_type   *type   = get_entity_type(entity);
-			adjust_method_type(type);
-			set_irn_mode(node, mode);
-			res = node;
-			goto own_replacement;
+
+			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 {
-			panic("unexpected projb: %+F (pred: %+F)", node, pred);
+			/* synthesize the 0/1 value */
+synth_zero_one:
+			res = config->create_set(node);
 		}
 		break;
 	}
 
 	case iro_Const: {
-		tarval *tv = get_Const_tarval(node);
+		ir_tarval *tv = get_Const_tarval(node);
 		if (tv == get_tarval_b_true()) {
-			tarval  *tv_one  = get_mode_one(mode);
-			res              = new_d_Const(dbgi, tv_one);
+			ir_tarval *tv_one = get_mode_one(mode);
+			res               = new_rd_Const(dbgi, irg, tv_one);
 		} else if (tv == get_tarval_b_false()) {
-			tarval  *tv_zero = get_mode_null(mode);
-			res              = new_d_Const(dbgi, tv_zero);
+			ir_tarval *tv_zero = get_mode_null(mode);
+			res                = new_rd_Const(dbgi, irg, tv_zero);
 		} else {
 			panic("invalid boolean const %+F", node);
 		}
@@ -344,113 +265,98 @@ synth_zero_one:
 	}
 
 	case iro_Unknown:
-		res = new_Unknown(mode);
+		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);
 	}
 
-	pdeq_putr(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)
 {
-	int i, arity;
-	bool changed = 0;
+	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 arity = get_irn_arity(node);
+	int i;
 	(void) env;
 
-	arity = get_irn_arity(node);
+	/* 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;
+	}
+
 	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) {
-		add_identities(current_ir_graph->value_table, 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);
+	size_t i;
+	size_t n;
 
-	config        = *nconfig;
-	lowered_nodes = new_pdeq();
-	lowered_type  = NULL;
+	config = nconfig;
 
-	/* ensure no optimisation touches muxes anymore */
-	set_irg_state(irg, IR_GRAPH_STATE_KEEP_MUX);
+	/* edges are used by part_block_edges in the ir_create_cond_set variant. */
+	edges_assure(irg);
 
+	set_irg_state(irg, IR_GRAPH_STATE_MODEB_LOWERED);
 	ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
 
-	adjust_method_type(type);
+	needs_lowering = NEW_ARR_F(needs_lowering_t, 0);
+
+	irg_walk_graph(irg, firm_clear_link, collect_needs_lowering, NULL);
 
-	set_opt_allow_conv_b(0);
-	irg_walk_graph(irg, firm_clear_link, NULL, NULL);
-	irg_walk_graph(irg, lower_mode_b_walker, NULL, NULL);
+	n = ARR_LEN(needs_lowering);
+	for (i = 0; i < n; ++i) {
+		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);
 
-	while (!pdeq_empty(lowered_nodes)) {
-		ir_node *node = (ir_node*) pdeq_getr(lowered_nodes);
-		maybe_kill_node(node);
+		if (needs_mode_b_input(node, input))
+			lowered = convert_to_modeb(lowered);
+		set_irn_n(node, input, lowered);
 	}
-	del_pdeq(lowered_nodes);
 
 	ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
-}
-
-struct pass_t {
-	ir_graph_pass_t             pass;
-	const lower_mode_b_config_t *config;
-};
-
-/**
- * Wrapper to run ir_lower_mode_b() as an ir_graph pass
- */
-static int pass_wrapper(ir_graph *irg, void *context)
-{
-	struct pass_t *pass = context;
 
-	ir_lower_mode_b(irg, pass->config);
-	return 0;
-}
+	DEL_ARR_F(needs_lowering);
 
-ir_graph_pass_t *ir_lower_mode_b_pass(
-	const char *name, const lower_mode_b_config_t *config)
-{
-	struct pass_t *pass = XMALLOCZ(struct pass_t);
-
-	pass->config = config;
-	return def_graph_pass_constructor(
-		&pass->pass, name ? name : "lower_mode_b", pass_wrapper);
+	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);
+	}
 }