added -(x >>u 31) and -(x >>s 31)
[libfirm] / ir / ir / iropt.c
index 195b235..02ed4e8 100644 (file)
@@ -1121,7 +1121,7 @@ static ir_node *equivalent_node_Or(ir_node *n) {
 }  /* equivalent_node_Or */
 
 /**
- * Optimize a & 0b1...1 = 0b1...1 & a =  a & a = a.
+ * Optimize a & 0b1...1 = 0b1...1 & a = a & a = (a|X) & a = a.
  */
 static ir_node *equivalent_node_And(ir_node *n) {
        ir_node *oldn = n;
@@ -1132,13 +1132,35 @@ static ir_node *equivalent_node_And(ir_node *n) {
        if (a == b) {
                n = a;    /* And has it's own neutral element */
                DBG_OPT_ALGSIM0(oldn, n, FS_OPT_AND);
-       } else if (classify_tarval(value_of(a)) == TV_CLASSIFY_ALL_ONE) {
+               return n;
+       }
+       if (classify_tarval(value_of(a)) == TV_CLASSIFY_ALL_ONE) {
                n = b;
                DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_AND);
-       } else if (classify_tarval(value_of(b)) == TV_CLASSIFY_ALL_ONE) {
+               return n;
+       }
+       if (classify_tarval(value_of(b)) == TV_CLASSIFY_ALL_ONE) {
                n = a;
                DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_AND);
+               return n;
+       }
+       if (is_Or(a)) {
+               if (b == get_Or_left(a) || b == get_Or_right(a)) {
+                       /* (a|X) & a */
+                       n = b;
+                       DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_AND);
+                       return n;
+               }
+       }
+       if (is_Or(b)) {
+               if (a == get_Or_left(b) || a == get_Or_right(b)) {
+                       /* a & (a|X) */
+                       n = a;
+                       DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_AND);
+                       return n;
+               }
        }
+
        return n;
 }  /* equivalent_node_And */
 
@@ -2001,23 +2023,44 @@ static ir_node *transform_node_Add(ir_node *n) {
                                }
                        }
                }
-               /* Here we rely on constants be on the RIGHT side */
-               if (get_mode_arithmetic(mode) == irma_twos_complement &&
-                        is_Not(a) && classify_Const(b) == CNST_ONE) {
-                       /* ~x + 1 = -x */
-                       ir_node *op = get_Not_op(a);
-                       ir_node *blk = get_irn_n(n, -1);
-                       n = new_rd_Minus(get_irn_dbg_info(n), current_ir_graph, blk, op, mode);
-                       DBG_OPT_ALGSIM0(oldn, n, FS_OPT_NOT_PLUS_1);
-                       return n;
+               if (get_mode_arithmetic(mode) == irma_twos_complement) {
+                       /* Here we rely on constants be on the RIGHT side */
+                       if (is_Not(a)) {
+                               ir_node *op = get_Not_op(a);
+
+                               if (classify_Const(b) == CNST_ONE) {
+                                       /* ~x + 1 = -x */
+                                       ir_node *blk = get_irn_n(n, -1);
+                                       n = new_rd_Minus(get_irn_dbg_info(n), current_ir_graph, blk, op, mode);
+                                       DBG_OPT_ALGSIM0(oldn, n, FS_OPT_NOT_PLUS_1);
+                                       return n;
+                               }
+                               if (op == b) {
+                                       /* ~x + x = -1 */
+                                       ir_node *blk = get_irn_n(n, -1);
+                                       n = new_r_Const(current_ir_graph, blk, mode, get_mode_minus_one(mode));
+                                       DBG_OPT_ALGSIM0(oldn, n, FS_OPT_ADD_X_NOT_X);
+                                       return n;
+                               }
+                       }
+                       if (is_Not(b)) {
+                               ir_node *op = get_Not_op(b);
+
+                               if (op == a) {
+                                       /* ~x + x = -1 */
+                                       ir_node *blk = get_irn_n(n, -1);
+                                       n = new_r_Const(current_ir_graph, blk, mode, get_mode_minus_one(mode));
+                                       DBG_OPT_ALGSIM0(oldn, n, FS_OPT_ADD_X_NOT_X);
+                                       return n;
+                               }
+                       }
                }
        }
        return n;
 }  /* transform_node_Add */
 
 /* returns -cnst */
-static ir_node* const_negate(ir_node* cnst)
-{
+static ir_node *const_negate(ir_node *cnst) {
        tarval   *tv    = tarval_neg(get_Const_tarval(cnst));
        dbg_info *dbgi  = get_irn_dbg_info(cnst);
        ir_graph *irg   = get_irn_irg(cnst);
@@ -2270,11 +2313,26 @@ restart:
 
                add = new_r_Add(current_ir_graph, blk, y, b, mode);
 
-               set_Sub_left(n, x);
-               set_Sub_right(n, add);
-               DBG_OPT_ALGSIM0(n, n, FS_OPT_SUB_SUB_X_Y_Z);
+               n = new_rd_Sub(get_irn_dbg_info(n), current_ir_graph, blk, x, add, mode);
+               DBG_OPT_ALGSIM0(oldn, n, FS_OPT_SUB_SUB_X_Y_Z);
                return n;
        }
+
+       if (get_mode_arithmetic(mode) == irma_twos_complement) {
+               if (is_Const(a) && is_Not(b)) {
+                       /* c - ~X = X + (c+1) */
+                       tarval *tv = get_Const_tarval(a);
+
+                       tv = tarval_add(tv, get_mode_one(mode));
+                       if (tv != tarval_bad) {
+                               ir_node *blk = get_irn_n(n, -1);
+                               ir_node *c = new_r_Const(current_ir_graph, blk, mode, tv);
+                               n = new_rd_Add(get_irn_dbg_info(n), current_ir_graph, blk, get_Not_op(b), c, mode);
+                               DBG_OPT_ALGSIM0(oldn, n, FS_OPT_SUB_C_NOT_X);
+                               return n;
+                       }
+               }
+       }
        return n;
 }  /* transform_node_Sub */
 
@@ -2812,7 +2870,6 @@ static ir_node *transform_bitwise_distributive(ir_node *n,
                                set_binop_right(n, c);
                        }
 
-
                        DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_SHIFT_AND);
                        return n;
                }
@@ -2825,14 +2882,14 @@ static ir_node *transform_bitwise_distributive(ir_node *n,
  * Transform an And.
  */
 static ir_node *transform_node_And(ir_node *n) {
-       ir_node *c, *oldn;
+       ir_node *c, *oldn = n;
        ir_node *a = get_And_left(n);
        ir_node *b = get_And_right(n);
 
        HANDLE_BINOP_PHI(tarval_and, a,b,c);
 
        /* we can evaluate 2 Projs of the same Cmp */
-       if(get_irn_mode(n) == mode_b && is_Proj(a) && is_Proj(b)) {
+       if (get_irn_mode(n) == mode_b && is_Proj(a) && is_Proj(b)) {
                ir_node *pred_a = get_Proj_pred(a);
                ir_node *pred_b = get_Proj_pred(b);
                if(pred_a == pred_b) {
@@ -2847,6 +2904,45 @@ static ir_node *transform_node_And(ir_node *n) {
                                           new_pnc);
                }
        }
+       if (is_Or(a)) {
+               if (is_Not(b)) {
+                       ir_node *op = get_Not_op(b);
+                       if (is_And(op)) {
+                               ir_node *ba = get_And_left(op);
+                               ir_node *bb = get_And_right(op);
+
+                               /* it's enough to test the following cases due to normalization! */
+                               if (get_Or_left(a) == ba && get_Or_right(a) == bb) {
+                                       /* (a|b) & ~(a&b) = a^b */
+                                       ir_node *block = get_nodes_block(n);
+
+                                       n = new_rd_Eor(get_irn_dbg_info(n), current_ir_graph, block, ba, bb, get_irn_mode(n));
+                                       DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_TO_EOR);
+                                       return n;
+                               }
+                       }
+               }
+       }
+       if (is_Or(b)) {
+               if (is_Not(a)) {
+                       ir_node *op = get_Not_op(a);
+                       if (is_And(op)) {
+                               ir_node *aa = get_And_left(op);
+                               ir_node *ab = get_And_right(op);
+
+                               /* it's enough to test the following cases due to normalization! */
+                               if (get_Or_left(b) == aa && get_Or_right(b) == ab) {
+                                       /* (a|b) & ~(a&b) = a^b */
+                                       ir_node *block = get_nodes_block(n);
+
+                                       n = new_rd_Eor(get_irn_dbg_info(n), current_ir_graph, block, aa, ab, get_irn_mode(n));
+                                       DBG_OPT_ALGSIM1(oldn, a, b, n, FS_OPT_TO_EOR);
+                                       return n;
+                               }
+                       }
+               }
+
+       }
 
        n = transform_bitwise_distributive(n, transform_node_And);
 
@@ -2945,6 +3041,7 @@ static ir_node *transform_node_Not(ir_node *n) {
  * Transform a Minus.
  * Optimize:
  *   -(~x) = x + 1
+ *   -(a-b) = b - a
  */
 static ir_node *transform_node_Minus(ir_node *n) {
        ir_node *c, *oldn = n;
@@ -2954,15 +3051,52 @@ static ir_node *transform_node_Minus(ir_node *n) {
        HANDLE_UNOP_PHI(tarval_neg,a,c);
 
        mode = get_irn_mode(a);
-       if (get_mode_arithmetic(mode) == irma_twos_complement && is_Not(a)) {
-               /* -(~x) = x + 1 */
-               ir_node *op   = get_Not_op(a);
-               tarval *tv    = get_mode_one(mode);
-               ir_node *blk  = get_irn_n(n, -1);
-               ir_node *c    = new_r_Const(current_ir_graph, blk, mode, tv);
-               n = new_rd_Add(get_irn_dbg_info(n), current_ir_graph, blk, op, c, mode);
-               DBG_OPT_ALGSIM2(oldn, a, n, FS_OPT_MINUS_NOT);
-       } else if (is_Sub(a)) {
+       if (get_mode_arithmetic(mode) == irma_twos_complement) {
+               /* the following rules are only to twos-complement */
+               if (is_Not(a)) {
+                       /* -(~x) = x + 1 */
+                       ir_node *op   = get_Not_op(a);
+                       tarval *tv    = get_mode_one(mode);
+                       ir_node *blk  = get_irn_n(n, -1);
+                       ir_node *c    = new_r_Const(current_ir_graph, blk, mode, tv);
+                       n = new_rd_Add(get_irn_dbg_info(n), current_ir_graph, blk, op, c, mode);
+                       DBG_OPT_ALGSIM2(oldn, a, n, FS_OPT_MINUS_NOT);
+                       return n;
+               }
+               if (is_Shr(a)) {
+                       ir_node *c = get_Shr_right(a);
+
+                       if (is_Const(c)) {
+                               tarval *tv = get_Const_tarval(c);
+
+                               if (tarval_is_long(tv) && get_tarval_long(tv) == get_mode_size_bits(mode) - 1) {
+                                       /* -(a >>u (size-1)) = a >>s (size-1) */
+                                       ir_node *v = get_Shr_left(a);
+
+                                       n = new_rd_Shrs(get_irn_dbg_info(n), current_ir_graph, get_irn_n(n, -1), v, c, mode);
+                                       DBG_OPT_ALGSIM2(oldn, a, n, FS_OPT_PREDICATE);
+                                       return n;
+                               }
+                       }
+               }
+               if (is_Shrs(a)) {
+                       ir_node *c = get_Shrs_right(a);
+
+                       if (is_Const(c)) {
+                               tarval *tv = get_Const_tarval(c);
+
+                               if (tarval_is_long(tv) && get_tarval_long(tv) == get_mode_size_bits(mode) - 1) {
+                                       /* -(a >>s (size-1)) = a >>u (size-1) */
+                                       ir_node *v = get_Shrs_left(a);
+
+                                       n = new_rd_Shr(get_irn_dbg_info(n), current_ir_graph, get_irn_n(n, -1), v, c, mode);
+                                       DBG_OPT_ALGSIM2(oldn, a, n, FS_OPT_PREDICATE);
+                                       return n;
+                               }
+                       }
+               }
+       }
+       if (is_Sub(a)) {
                /* - (a-b) = b - a */
                ir_node *la  = get_Sub_left(a);
                ir_node *ra  = get_Sub_right(a);
@@ -2970,6 +3104,7 @@ static ir_node *transform_node_Minus(ir_node *n) {
 
                n = new_rd_Sub(get_irn_dbg_info(n), current_ir_graph, blk, ra, la, mode);
                DBG_OPT_ALGSIM2(oldn, a, n, FS_OPT_MINUS_SUB);
+               return n;
        }
 
        return n;
@@ -3261,7 +3396,7 @@ static ir_node *transform_node_Proj_Cmp(ir_node *proj) {
                                        left  = lr;
                                        right = rl;
                                        changed |= 1;
-                               } else if (lr = rl) {
+                               } else if (lr == rl) {
                                        /* a + X CMP X + b ==> a CMP b */
                                        left  = ll;
                                        right = rr;
@@ -3299,6 +3434,8 @@ static ir_node *transform_node_Proj_Cmp(ir_node *proj) {
                                        changed |= 1;
                                }
                                break;
+                       default:
+                               break;
                        }
 
                }
@@ -3366,16 +3503,23 @@ static ir_node *transform_node_Proj_Cmp(ir_node *proj) {
                         * be optimized, see this:
                         * -MININT < 0 =/=> MININT > 0 !!!
                         */
-                       if (get_opt_constant_folding() && get_irn_op(left) == op_Minus &&
+                       if (is_Minus(left) &&
                                (!mode_overflow_on_unary_Minus(mode) ||
                                (mode_is_int(mode) && (proj_nr == pn_Cmp_Eq || proj_nr == pn_Cmp_Lg)))) {
-                               left = get_Minus_op(left);
                                tv = tarval_neg(tv);
 
                                if (tv != tarval_bad) {
+                                       left = get_Minus_op(left);
                                        proj_nr = get_inversed_pnc(proj_nr);
                                        changed |= 2;
                                }
+                       } else if (is_Not(left) && (proj_nr == pn_Cmp_Eq || proj_nr == pn_Cmp_Lg)) {
+                               tv = tarval_not(tv);
+
+                               if (tv != tarval_bad) {
+                                       left = get_Not_op(left);
+                                       changed |= 2;
+                               }
                        }
 
                        /* for integer modes, we have more */
@@ -3412,14 +3556,12 @@ static ir_node *transform_node_Proj_Cmp(ir_node *proj) {
                                if (proj_nr == pn_Cmp_Eq || proj_nr == pn_Cmp_Lg) {
 
                                        /* a-b == 0  ==>  a == b,  a-b != 0  ==>  a != b */
-                                       if (classify_tarval(tv) == TV_CLASSIFY_NULL && get_irn_op(left) == op_Sub) {
-                                               right = get_Sub_right(left);
+                                       if (classify_tarval(tv) == TV_CLASSIFY_NULL && is_Sub(left)) {
+                                               right =get_Sub_right(left);
                                                left  = get_Sub_left(left);
 
                                                tv = value_of(right);
-                                               if (tv != tarval_bad) {
-                                                       changed = 1;
-                                               }
+                                               changed = 1;
                                        }
 
                                        if (tv != tarval_bad) {
@@ -3522,8 +3664,7 @@ static ir_node *transform_node_Proj_Cmp(ir_node *proj) {
                        right = new_Const(mode, tv);
 
                /* create a new compare */
-               n = new_rd_Cmp(get_irn_dbg_info(n), current_ir_graph, block,
-                       left, right);
+               n = new_rd_Cmp(get_irn_dbg_info(n), current_ir_graph, block, left, right);
 
                set_Proj_pred(proj, n);
                set_Proj_proj(proj, proj_nr);