Hi,
>> That's not what Richard meant. We already have:
Done. As per the comments.
Please find attached the modified patch as per your comments.
Please review them and let me know if any further modifications are required.
Thanks,
Naveen
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index de45a2c..1e7fbb4 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -9803,20 +9803,6 @@ fold_binary_loc (location_t loc,
goto associate;
case MULT_EXPR:
- /* (-A) * (-B) -> A * B */
- if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
- return fold_build2_loc (loc, MULT_EXPR, type,
- fold_convert_loc (loc, type,
- TREE_OPERAND (arg0, 0)),
- fold_convert_loc (loc, type,
- negate_expr (arg1)));
- if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
- return fold_build2_loc (loc, MULT_EXPR, type,
- fold_convert_loc (loc, type,
- negate_expr (arg0)),
- fold_convert_loc (loc, type,
- TREE_OPERAND (arg1, 0)));
-
if (! FLOAT_TYPE_P (type))
{
/* Transform x * -C into -x * C if x is easily negatable. */
@@ -9830,16 +9816,6 @@ fold_binary_loc (location_t loc,
negate_expr (arg0)),
tem);
- /* (a * (1 << b)) is (a << b) */
- if (TREE_CODE (arg1) == LSHIFT_EXPR
- && integer_onep (TREE_OPERAND (arg1, 0)))
- return fold_build2_loc (loc, LSHIFT_EXPR, type, op0,
- TREE_OPERAND (arg1, 1));
- if (TREE_CODE (arg0) == LSHIFT_EXPR
- && integer_onep (TREE_OPERAND (arg0, 0)))
- return fold_build2_loc (loc, LSHIFT_EXPR, type, op1,
- TREE_OPERAND (arg0, 1));
-
/* (A + A) * C -> A * 2 * C */
if (TREE_CODE (arg0) == PLUS_EXPR
&& TREE_CODE (arg1) == INTEGER_CST
@@ -9882,21 +9858,6 @@ fold_binary_loc (location_t loc,
}
else
{
- /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
- the result for floating point types due to rounding so it is applied
- only if -fassociative-math was specify. */
- if (flag_associative_math
- && TREE_CODE (arg0) == RDIV_EXPR
- && TREE_CODE (arg1) == REAL_CST
- && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
- {
- tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
- arg1);
- if (tem)
- return fold_build2_loc (loc, RDIV_EXPR, type, tem,
- TREE_OPERAND (arg0, 1));
- }
-
/* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
if (operand_equal_p (arg0, arg1, 0))
{
@@ -10053,22 +10014,6 @@ fold_binary_loc (location_t loc,
goto bit_rotate;
case BIT_AND_EXPR:
- /* ~X & X, (X == 0) & X, and !X & X are always zero. */
- if ((TREE_CODE (arg0) == BIT_NOT_EXPR
- || TREE_CODE (arg0) == TRUTH_NOT_EXPR
- || (TREE_CODE (arg0) == EQ_EXPR
- && integer_zerop (TREE_OPERAND (arg0, 1))))
- && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
- return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
-
- /* X & ~X , X & (X == 0), and X & !X are always zero. */
- if ((TREE_CODE (arg1) == BIT_NOT_EXPR
- || TREE_CODE (arg1) == TRUTH_NOT_EXPR
- || (TREE_CODE (arg1) == EQ_EXPR
- && integer_zerop (TREE_OPERAND (arg1, 1))))
- && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
- return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
-
/* Fold (X ^ 1) & 1 as (X & 1) == 0. */
if (TREE_CODE (arg0) == BIT_XOR_EXPR
&& INTEGRAL_TYPE_P (type)
diff --git a/gcc/match.pd b/gcc/match.pd
index f3813d8..04b6138 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -324,6 +324,27 @@ along with GCC; see the file COPYING3. If not see
(if (real_isinteger (&TREE_REAL_CST (@1), &n) && (n & 1) == 0)
(pows @0 @1))))))
+/* Fold (a * (1 << b)) into (a << b) */
+(simplify
+ (mult:c @0 (convert? (lshift integer_onep@1 @2)))
+ (if (! FLOAT_TYPE_P (type)
+ && tree_nop_conversion_p (type, TREE_TYPE (@1)))
+ (lshift @0 @2)))
+
+/* Fold (C1/X)*C2 into (C1*C2)/X. */
+(simplify
+ (mult (rdiv:s REAL_CST@0 @1) REAL_CST@2)
+ (if (flag_associative_math)
+ (with
+ { tree tem = const_binop (MULT_EXPR, type, @0, @2); }
+ (if (tem)
+ (rdiv { tem; } @1)))))
+
+/* Simplify ~X & X as zero. */
+(simplify
+ (bit_and:c (convert? @0) (convert? (bit_not @0)))
+ { build_zero_cst (type); })
+
/* X % Y is smaller than Y. */
(for cmp (lt ge)
(simplify
@@ -543,6 +564,13 @@ along with GCC; see the file COPYING3. If not see
(match negate_expr_p
VECTOR_CST
(if (FLOAT_TYPE_P (TREE_TYPE (type)) || TYPE_OVERFLOW_WRAPS (type))))
+
+/* (-A) * (-B) -> A * B */
+(simplify
+ (mult:c (convert1? (negate @0)) (convert2? negate_expr_p@1))
+ (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
+ && tree_nop_conversion_p (type, TREE_TYPE (@1)))
+ (mult (convert @0) (convert (negate @1)))))
/* -(A + B) -> (-B) - A. */
(simplify
@@ -629,6 +657,8 @@ along with GCC; see the file COPYING3. If not see
(truth_not @0))
(match (logical_inverted_value @0)
+ (truth_not @0))
+(match (logical_inverted_value @0)
(bit_not truth_valued_p@0))
(match (logical_inverted_value @0)
(eq @0 integer_zerop))
@@ -637,10 +667,10 @@ along with GCC; see the file COPYING3. If not see
(match (logical_inverted_value @0)
(bit_xor truth_valued_p@0 integer_truep))
-/* X & !X -> 0. */
+/* X & !X or X & ~X -> 0. */
(simplify
(bit_and:c @0 (logical_inverted_value @0))
- { build_zero_cst (type); })
+ { build_zero_cst (type); })
/* X | !X and X ^ !X -> 1, , if X is truth-valued. */
(for op (bit_ior bit_xor)
(simplify
