X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fopt%2Fconvopt.c;h=cfee6ee5cc88794d80ab81c4c36cc78f5e4bbe85;hb=e0a2eca7e1d13c2f1ccb8a70479039c01c0c69ef;hp=3ee9687b854c5c8f0a439237eab0ab760203b747;hpb=3cd2c1a3415e590caec9051ec33fe9ca2b2ae4dc;p=libfirm

diff --git a/ir/opt/convopt.c b/ir/opt/convopt.c
index 3ee9687b8..cfee6ee5c 100644
--- a/ir/opt/convopt.c
+++ b/ir/opt/convopt.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1995-2007 University of Karlsruhe.  All right reserved.
+ * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
  *
  * This file is part of libFirm.
  *
@@ -36,9 +36,7 @@
  * TODO: * try to optimize cmp modes
  *       * decide when it is useful to move the convs through phis
  */
-#ifdef HAVE_CONFIG_H
 #include "config.h"
-#endif
 
 #include "iroptimize.h"
 
@@ -54,7 +52,7 @@
 
 DEBUG_ONLY(static firm_dbg_module_t *dbg);
 
-static INLINE int imin(int a, int b) { return a < b ? a : b; }
+static inline int imin(int a, int b) { return a < b ? a : b; }
 
 static
 int is_optimizable_node(const ir_node *node)
@@ -87,7 +85,7 @@ int is_downconv(ir_mode *src_mode, ir_mode *dest_mode)
 	return
 		mode_is_int(src_mode) &&
 		mode_is_int(dest_mode) &&
-		get_mode_size_bits(dest_mode) < get_mode_size_bits(src_mode);
+		get_mode_size_bits(dest_mode) <= get_mode_size_bits(src_mode);
 }
 
 static
@@ -106,18 +104,17 @@ int get_conv_costs(const ir_node *node, ir_mode *dest_mode)
 		return conv_const_tv(node, dest_mode) == tarval_bad ? 1 : 0;
 	}
 
+	if (is_Conv(node) &&
+			is_downconv(mode, dest_mode) &&
+			get_irn_mode(get_Conv_op(node)) == dest_mode) {
+		return -1;
+	}
+
 	if (get_irn_n_edges(node) > 1) {
-		if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
-			return get_conv_costs(get_Conv_op(node), dest_mode) - 1;
-		}
 		DB((dbg, LEVEL_3, "multi outs at %+F\n", node));
 		return 1;
 	}
 
-	if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
-		return get_conv_costs(get_Conv_op(node), dest_mode) - 1;
-	}
-
 #if 0 // TODO
 	/* Take the minimum of the conversion costs for Phi predecessors as only one
 	 * branch is actually executed at a time */
@@ -137,12 +134,21 @@ int get_conv_costs(const ir_node *node, ir_mode *dest_mode)
 	}
 #endif
 
+	if (!is_downconv(mode, dest_mode)) {
+		return 1;
+	}
+
+	if (is_Conv(node)) {
+		return get_conv_costs(get_Conv_op(node), dest_mode) - 1;
+	}
+
 	if (!is_optimizable_node(node)) {
 		return 1;
 	}
 
 	costs = 0;
-	arity = get_irn_arity(node);
+	// The shift count does not participate in the conv optimisation
+	arity = is_Shl(node) ? 1 : get_irn_arity(node);
 	for (i = 0; i < arity; ++i) {
 		ir_node *pred = get_irn_n(node, i);
 		costs += imin(get_conv_costs(pred, dest_mode), 1);
@@ -161,10 +167,11 @@ static ir_node *place_conv(ir_node *node, ir_mode *dest_mode)
 static
 ir_node *conv_transform(ir_node *node, ir_mode *dest_mode)
 {
-	size_t arity;
-	size_t i;
+	ir_mode *mode = get_irn_mode(node);
+	size_t   arity;
+	size_t   i;
 
-	if (get_irn_mode(node) == dest_mode)
+	if (mode == dest_mode)
 		return node;
 
 	if (is_Const(node)) {
@@ -173,18 +180,25 @@ ir_node *conv_transform(ir_node *node, ir_mode *dest_mode)
 		if (tv == tarval_bad) {
 			return place_conv(node, dest_mode);
 		} else {
-			return new_Const(dest_mode, tv);
+			return new_Const(tv);
 		}
 	}
 
+	if (is_Conv(node) &&
+			is_downconv(mode, dest_mode) &&
+			get_irn_mode(get_Conv_op(node)) == dest_mode) {
+		return get_Conv_op(node);
+	}
+
 	if (get_irn_n_edges(node) > 1) {
-		if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
-			return conv_transform(get_Conv_op(node), dest_mode);
-		}
 		return place_conv(node, dest_mode);
 	}
 
-	if (is_Conv(node) && is_downconv(get_irn_mode(node), dest_mode)) {
+	if (!is_downconv(mode, dest_mode)) {
+		return place_conv(node, dest_mode);
+	}
+
+	if (is_Conv(node)) {
 		return conv_transform(get_Conv_op(node), dest_mode);
 	}
 
@@ -192,7 +206,8 @@ ir_node *conv_transform(ir_node *node, ir_mode *dest_mode)
 		return place_conv(node, dest_mode);
 	}
 
-	arity = get_irn_arity(node);
+	// The shift count does not participate in the conv optimisation
+	arity = is_Shl(node) ? 1 : get_irn_arity(node);
 	for (i = 0; i < arity; i++) {
 		ir_node *pred = get_irn_n(node, i);
 		ir_node *transformed;
@@ -247,6 +262,9 @@ void conv_opt_walker(ir_node *node, void *data)
 	mode      = get_irn_mode(node);
 	pred_mode = get_irn_mode(pred);
 
+	if (mode_is_reference(mode) || mode_is_reference(pred_mode))
+		return;
+
 	if (!is_Phi(pred) && !is_downconv(pred_mode, mode))
 		return;
 
@@ -262,7 +280,7 @@ void conv_opt_walker(ir_node *node, void *data)
 	}
 }
 
-void conv_opt(ir_graph *irg)
+int conv_opt(ir_graph *irg)
 {
 	char invalidate = 0;
 	FIRM_DBG_REGISTER(dbg, "firm.opt.conv");
@@ -280,4 +298,5 @@ void conv_opt(ir_graph *irg)
 	if (invalidate) {
 		set_irg_outs_inconsistent(irg);
 	}
+	return invalidate;
 }