localopt/lower_dw opt: a==b && c==d => (a^b)|(c^d)==0
authorMatthias Braun <matze@braunis.de>
Sun, 29 May 2011 11:33:26 +0000 (13:33 +0200)
committerMatthias Braun <matze@braunis.de>
Mon, 30 May 2011 11:05:47 +0000 (13:05 +0200)
ir/ir/iropt.c
ir/lower/lower_dw.c

index 541e406..111d1b3 100644 (file)
@@ -2951,20 +2951,21 @@ static ir_node *transform_node_And(ir_node *n)
                        ir_relation new_relation = a_relation & b_relation;
                        return new_rd_Cmp(dbgi, block, a_left, a_right, new_relation);
                }
-               /* Cmp(a==0) and Cmp(b==0) can be optimized to Cmp(a|b==0) */
-               if (is_Const(a_right) && is_Const_null(a_right)
-                               && is_Const(b_right) && is_Const_null(b_right)
-                               && a_relation == b_relation && a_relation == ir_relation_equal
-                               && !mode_is_float(get_irn_mode(a_left))
-                               && !mode_is_float(get_irn_mode(b_left))) {
-                       dbg_info *dbgi     = get_irn_dbg_info(n);
-                       ir_node  *block    = get_nodes_block(n);
-                       ir_mode  *mode     = get_irn_mode(a_left);
-                       ir_node  *n_b_left = get_irn_mode(b_left) != mode ?
-                               new_rd_Conv(dbgi, block, b_left, mode) : b_left;
-                       ir_node  *or       = new_rd_Or(dbgi, block, a_left, n_b_left, mode);
-                       ir_graph *irg      = get_irn_irg(n);
-                       ir_node  *zero     = create_zero_const(irg, mode);
+               /* Cmp(a==b) and Cmp(c==d) can be optimized to Cmp((a^b)|(c^d)==0) */
+               if (a_relation == b_relation && a_relation == ir_relation_equal
+                   && !mode_is_float(get_irn_mode(a_left))
+                   && !mode_is_float(get_irn_mode(b_left))
+                   && values_in_mode(get_irn_mode(a_left), get_irn_mode(b_left))) {
+                       dbg_info *dbgi   = get_irn_dbg_info(n);
+                       ir_node  *block  = get_nodes_block(n);
+                       ir_mode  *a_mode = get_irn_mode(a_left);
+                       ir_mode  *b_mode = get_irn_mode(b_left);
+                       ir_node  *xora   = new_rd_Eor(dbgi, block, a_left, a_right, a_mode);
+                       ir_node  *xorb   = new_rd_Eor(dbgi, block, b_left, b_right, b_mode);
+                       ir_node  *conv   = new_rd_Conv(dbgi, block, xorb, a_mode);
+                       ir_node  *or     = new_rd_Or(dbgi, block, xora, conv, a_mode);
+                       ir_graph *irg    = get_irn_irg(n);
+                       ir_node  *zero   = create_zero_const(irg, a_mode);
                        return new_rd_Cmp(dbgi, block, or, zero, ir_relation_equal);
                }
        }
@@ -4659,20 +4660,19 @@ static ir_node *transform_node_Or_Rotl(ir_node *irn_or)
        return n;
 }  /* transform_node_Or_Rotl */
 
-static bool is_cmp_unequal_zero(const ir_node *node)
+static bool is_cmp_unequal(const ir_node *node)
 {
        ir_relation relation = get_Cmp_relation(node);
        ir_node    *left     = get_Cmp_left(node);
        ir_node    *right    = get_Cmp_right(node);
        ir_mode    *mode     = get_irn_mode(left);
 
-       if (!is_Const(right) || !is_Const_null(right))
-               return false;
-       if (mode_is_signed(mode)) {
-               return relation == ir_relation_less_greater;
-       } else {
+       if (relation == ir_relation_less_greater)
+               return true;
+
+       if (!mode_is_signed(mode) && is_Const(right) && is_Const_null(right))
                return relation == ir_relation_greater;
-       }
+       return false;
 }
 
 /**
@@ -4712,18 +4712,21 @@ static ir_node *transform_node_Or(ir_node *n)
                        ir_relation new_relation = a_relation | b_relation;
                        return new_rd_Cmp(dbgi, block, a_left, a_right, new_relation);
                }
-               /* Cmp(a!=0) or Cmp(b!=0) => Cmp(a|b != 0) */
-               if (is_cmp_unequal_zero(a) && is_cmp_unequal_zero(b)
-                               && !mode_is_float(get_irn_mode(a_left))
-                               && !mode_is_float(get_irn_mode(b_left))) {
-                       ir_graph *irg      = get_irn_irg(n);
-                       dbg_info *dbgi     = get_irn_dbg_info(n);
-                       ir_node  *block    = get_nodes_block(n);
-                       ir_mode  *mode     = get_irn_mode(a_left);
-                       ir_node  *n_b_left = get_irn_mode(b_left) != mode ?
-                               new_rd_Conv(dbgi, block, b_left, mode) : b_left;
-                       ir_node  *or   = new_rd_Or(dbgi, block, a_left, n_b_left, mode);
-                       ir_node  *zero = create_zero_const(irg, mode);
+               /* Cmp(a!=b) or Cmp(c!=d) => Cmp((a^b)|(c^d) != 0) */
+               if (is_cmp_unequal(a) && is_cmp_unequal(b)
+                   && !mode_is_float(get_irn_mode(a_left))
+                   && !mode_is_float(get_irn_mode(b_left))
+                   && values_in_mode(get_irn_mode(a_left), get_irn_mode(b_left))) {
+                       ir_graph *irg    = get_irn_irg(n);
+                       dbg_info *dbgi   = get_irn_dbg_info(n);
+                       ir_node  *block  = get_nodes_block(n);
+                       ir_mode  *a_mode = get_irn_mode(a_left);
+                       ir_mode  *b_mode = get_irn_mode(b_left);
+                       ir_node  *xora   = new_rd_Eor(dbgi, block, a_left, a_right, a_mode);
+                       ir_node  *xorb   = new_rd_Eor(dbgi, block, b_left, b_right, b_mode);
+                       ir_node  *conv   = new_rd_Conv(dbgi, block, xorb, a_mode);
+                       ir_node  *or     = new_rd_Or(dbgi, block, xora, conv, a_mode);
+                       ir_node  *zero   = create_zero_const(irg, a_mode);
                        return new_rd_Cmp(dbgi, block, or, zero, ir_relation_less_greater);
                }
        }
index 217bc0f..484f9da 100644 (file)
@@ -1168,7 +1168,7 @@ static void lower_Not(ir_node *node, ir_mode *mode)
        ir_set_dw_lowered(node, res_low, res_high);
 }
 
-static bool is_equality_cmp_0(const ir_node *node)
+static bool is_equality_cmp(const ir_node *node)
 {
        ir_relation relation = get_Cmp_relation(node);
        ir_node    *left     = get_Cmp_left(node);
@@ -1178,10 +1178,11 @@ static bool is_equality_cmp_0(const ir_node *node)
        /* this probably makes no sense if unordered is involved */
        assert(!mode_is_float(mode));
 
+       if (relation == ir_relation_equal || relation == ir_relation_less_greater)
+               return true;
+
        if (!is_Const(right) || !is_Const_null(right))
                return false;
-       if (relation == ir_relation_equal)
-               return true;
        if (mode_is_signed(mode)) {
                return relation == ir_relation_less_greater;
        } else {
@@ -1272,12 +1273,16 @@ static void lower_Cond(ir_node *node, ir_mode *mode)
        dbg      = get_irn_dbg_info(sel);
        relation = get_Cmp_relation(sel);
 
-       if (is_equality_cmp_0(sel)) {
-               /* x ==/!= 0 ==> or(low,high) ==/!= 0 */
-               ir_mode *mode   = env->low_unsigned;
-               ir_node *low    = new_r_Conv(block, lentry->low_word, mode);
-               ir_node *high   = new_r_Conv(block, lentry->high_word, mode);
-               ir_node *ornode = new_rd_Or(dbg, block, low, high, mode);
+       if (is_equality_cmp(sel)) {
+               /* x ==/!= y ==> or(x_low^y_low,x_high^y_high) ==/!= 0 */
+               ir_mode *mode       = env->low_unsigned;
+               ir_node *low_left   = new_rd_Conv(dbg, block, lentry->low_word, mode);
+               ir_node *high_left  = new_rd_Conv(dbg, block, lentry->high_word, mode);
+               ir_node *low_right  = new_rd_Conv(dbg, block, rentry->low_word, mode);
+               ir_node *high_right = new_rd_Conv(dbg, block, rentry->high_word, mode);
+               ir_node *xor_low    = new_rd_Eor(dbg, block, low_left, low_right, mode);
+               ir_node *xor_high   = new_rd_Eor(dbg, block, high_left, high_right, mode);
+               ir_node *ornode = new_rd_Or(dbg, block, xor_low, xor_high, mode);
                ir_node *cmp    = new_rd_Cmp(dbg, block, ornode, new_r_Const_long(irg, mode, 0), relation);
                set_Cond_selector(node, cmp);
                return;
@@ -1530,13 +1535,17 @@ static void lower_Cmp(ir_node *cmp, ir_mode *m)
        dbg      = get_irn_dbg_info(cmp);
 
        /* easy case for x ==/!= 0 (see lower_Cond for details) */
-       if (is_equality_cmp_0(cmp)) {
-               ir_graph *irg     = get_irn_irg(cmp);
-               ir_mode  *mode    = env->low_unsigned;
-               ir_node  *low     = new_r_Conv(block, lentry->low_word, mode);
-               ir_node  *high    = new_r_Conv(block, lentry->high_word, mode);
-               ir_node  *ornode  = new_rd_Or(dbg, block, low, high, mode);
-               ir_node  *new_cmp = new_rd_Cmp(dbg, block, ornode, new_r_Const_long(irg, mode, 0), relation);
+       if (is_equality_cmp(cmp)) {
+               ir_graph *irg        = get_irn_irg(cmp);
+               ir_mode  *mode       = env->low_unsigned;
+               ir_node  *low_left   = new_rd_Conv(dbg, block, lentry->low_word, mode);
+               ir_node  *high_left  = new_rd_Conv(dbg, block, lentry->high_word, mode);
+               ir_node  *low_right  = new_rd_Conv(dbg, block, rentry->low_word, mode);
+               ir_node  *high_right = new_rd_Conv(dbg, block, rentry->high_word, mode);
+               ir_node  *xor_low    = new_rd_Eor(dbg, block, low_left, low_right, mode);
+               ir_node  *xor_high   = new_rd_Eor(dbg, block, high_left, high_right, mode);
+               ir_node  *ornode     = new_rd_Or(dbg, block, xor_low, xor_high, mode);
+               ir_node  *new_cmp    = new_rd_Cmp(dbg, block, ornode, new_r_Const_long(irg, mode, 0), relation);
                exchange(cmp, new_cmp);
                return;
        }