X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fopt%2Freassoc.c;h=319a80a395375af28b319ae35ece4bc4b9cef418;hb=3b7718957d840de642745275607f2e24f8b33f02;hp=2f4c26a59fe6fb1216ad00e8ab9f022df755fab7;hpb=802484dd3f5047d512b2496e1647aaed127a1a8c;p=libfirm

diff --git a/ir/opt/reassoc.c b/ir/opt/reassoc.c
index 2f4c26a59..319a80a39 100644
--- a/ir/opt/reassoc.c
+++ b/ir/opt/reassoc.c
@@ -25,6 +25,7 @@
  */
 #include "config.h"
 
+#include "iroptimize.h"
 #include "iropt_t.h"
 #include "irnode_t.h"
 #include "irgraph_t.h"
@@ -222,7 +223,7 @@ static ir_mode *get_mode_from_ops(ir_node *op1, ir_node *op2)
 static int reassoc_commutative(ir_node **node)
 {
 	ir_node *n     = *node;
-	ir_op *op      = get_irn_op(n);
+	ir_op   *op    = get_irn_op(n);
 	ir_node *block = get_nodes_block(n);
 	ir_node *t1, *c1;
 
@@ -306,6 +307,55 @@ static int reassoc_commutative(ir_node **node)
 			}
 		}
 	}
+	if (get_irn_op(c1) == op) {
+		ir_node *t = c1;
+		c1 = t1;
+		t1 = t;
+	}
+	if (get_irn_op(t1) == op) {
+		ir_node *l = get_binop_left(t1);
+		ir_node *r = get_binop_right(t1);
+		const_class_t c_r;
+
+		if (r == c1) {
+			ir_node *t = r;
+			r = l;
+			l = t;
+		}
+		c_r = get_const_class(r, block);
+		if (c_r != NO_CONSTANT) {
+			/*
+			 * Beware: don't do the following op if a constant was
+			 * placed below, else we will fall into a loop.
+			 */
+			return 0;
+		}
+
+		if (l == c1) {
+			/* convert x .OP. (x .OP. y) => y .OP. (x .OP. x) */
+			ir_mode *mode_res = get_irn_mode(n);
+			ir_mode *mode_c1  = get_irn_mode(c1);
+			ir_node *irn, *in[2];
+
+			in[0] = c1;
+			in[1] = c1;
+
+			in[1] = optimize_node(new_ir_node(NULL, current_ir_graph, block, op, mode_c1, 2, in));
+			in[0] = r;
+
+			irn   = optimize_node(new_ir_node(NULL, current_ir_graph, block, op, mode_res, 2, in));
+
+			DBG((dbg, LEVEL_5, "Applied: %n .%s. (%n .%s. %n) => %n .%s. (%n .%s. %n)\n",
+				c1, get_irn_opname(n), l, get_irn_opname(n), r,
+				r, get_irn_opname(n), c1, get_irn_opname(n), c1));
+
+			if (n != irn) {
+				exchange(n, irn);
+				*node = irn;
+				return 1;
+			}
+		}
+	}
 	return 0;
 }  /* reassoc_commutative */
 
@@ -499,7 +549,8 @@ static int reassoc_Mul(ir_node **node)
 /**
  * Reassociate Shl. We transform Shl(x, const) into Mul's if possible.
  */
-static int reassoc_Shl(ir_node **node) {
+static int reassoc_Shl(ir_node **node)
+{
 	ir_node *n = *node;
 	ir_node *c = get_Shl_right(n);
 	ir_node *x, *blk, *irn;
@@ -617,7 +668,8 @@ static void do_reassociation(walker_t *wenv)
  *
  * If the earliest block is the start block, return curr_blk instead
  */
-static ir_node *earliest_block(ir_node *a, ir_node *b, ir_node *curr_blk) {
+static ir_node *earliest_block(ir_node *a, ir_node *b, ir_node *curr_blk)
+{
 	ir_node *blk_a = get_nodes_block(a);
 	ir_node *blk_b = get_nodes_block(b);
 	ir_node *res;
@@ -641,7 +693,8 @@ static ir_node *earliest_block(ir_node *a, ir_node *b, ir_node *curr_blk) {
  * Handling SymConsts as const might be not a good idea for all
  * architectures ...
  */
-static int is_constant_expr(ir_node *irn) {
+static int is_constant_expr(ir_node *irn)
+{
 	ir_op *op;
 
 	switch (get_irn_opcode(irn)) {
@@ -664,7 +717,8 @@ static int is_constant_expr(ir_node *irn) {
 /**
  * Apply distributive Law for Mul and Add/Sub
  */
-static int reverse_rule_distributive(ir_node **node) {
+static int reverse_rule_distributive(ir_node **node)
+{
 	ir_node *n = *node;
 	ir_node *left  = get_binop_left(n);
 	ir_node *right = get_binop_right(n);
@@ -746,7 +800,8 @@ transform:
 /**
  * Move Constants towards the root.
  */
-static int move_consts_up(ir_node **node) {
+static int move_consts_up(ir_node **node)
+{
 	ir_node *n = *node;
 	ir_op *op;
 	ir_node *l, *r, *a, *b, *c, *blk, *irn, *in[2];
@@ -847,7 +902,8 @@ transform:
 /**
  * Apply the rules in reverse order, removing code that was not collapsed
  */
-static void reverse_rules(ir_node *node, void *env) {
+static void reverse_rules(ir_node *node, void *env)
+{
 	walker_t *wenv = env;
 	ir_mode *mode = get_irn_mode(node);
 	int res;
@@ -936,7 +992,8 @@ int optimize_reassociation(ir_graph *irg)
 }  /* optimize_reassociation */
 
 /* create a pass for the reassociation */
-ir_graph_pass_t *optimize_reassociation_pass(const char *name) {
+ir_graph_pass_t *optimize_reassociation_pass(const char *name)
+{
 	return def_graph_pass_ret(name ? name : "reassoc", optimize_reassociation);
 }  /* optimize_reassociation_pass */