static int all_ones_mask_p (const_tree, int);
static tree sign_bit_p (tree, const_tree);
static int simple_operand_p (const_tree);
+static bool simple_operand_p_2 (tree);
static tree range_binop (enum tree_code, tree, tree, int, tree, int);
static tree range_predecessor (tree);
static tree range_successor (tree);
static tree fold_range_test (location_t, enum tree_code, tree, tree, tree);
static tree fold_cond_expr_with_comparison (location_t, tree, tree, tree, tree);
static tree unextend (tree, int, int, tree);
-static tree fold_truthop (location_t, enum tree_code, tree, tree, tree);
static tree optimize_minmax_comparison (location_t, enum tree_code,
tree, tree, tree);
static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
return lhs;
}
\f
-/* Subroutine for fold_truthop: decode a field reference.
+/* Subroutine for fold_truth_andor_1: decode a field reference.
If EXP is a comparison reference, we return the innermost reference.
return NULL_TREE;
}
-/* Subroutine for fold_truthop: determine if an operand is simple enough
+/* Subroutine for fold_truth_andor_1: determine if an operand is simple enough
to be evaluated unconditionally. */
static int
STRIP_NOPS (exp);
return (CONSTANT_CLASS_P (exp)
- || TREE_CODE (exp) == SSA_NAME
+ || TREE_CODE (exp) == SSA_NAME
|| (DECL_P (exp)
&& ! TREE_ADDRESSABLE (exp)
&& ! TREE_THIS_VOLATILE (exp)
registers aren't expensive. */
&& (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
}
+
+/* Subroutine for fold_truth_andor: determine if an operand is simple enough
+ to be evaluated unconditionally.
+ I addition to simple_operand_p, we assume that comparisons and logic-not
+ operations are simple, if their operands are simple, too. */
+
+static bool
+simple_operand_p_2 (tree exp)
+{
+ enum tree_code code;
+
+ /* Strip any conversions that don't change the machine mode. */
+ STRIP_NOPS (exp);
+
+ code = TREE_CODE (exp);
+
+ if (TREE_SIDE_EFFECTS (exp)
+ || tree_could_trap_p (exp))
+ return false;
+
+ if (TREE_CODE_CLASS (code) == tcc_comparison)
+ return (simple_operand_p (TREE_OPERAND (exp, 0))
+ && simple_operand_p (TREE_OPERAND (exp, 1)));
+
+ if (code == TRUTH_NOT_EXPR)
+ return simple_operand_p_2 (TREE_OPERAND (exp, 0));
+
+ return simple_operand_p (exp);
+}
+
\f
/* The following functions are subroutines to fold_range_test and allow it to
try to change a logical combination of comparisons into a range test.
return 0;
}
\f
-/* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
+/* Subroutine for fold_truth_andor_1: C is an INTEGER_CST interpreted as a P
bit value. Arrange things so the extra bits will be set to zero if and
only if C is signed-extended to its full width. If MASK is nonzero,
it is an INTEGER_CST that should be AND'ed with the extra bits. */
We return the simplified tree or 0 if no optimization is possible. */
static tree
-fold_truthop (location_t loc, enum tree_code code, tree truth_type,
- tree lhs, tree rhs)
+fold_truth_andor_1 (location_t loc, enum tree_code code, tree truth_type,
+ tree lhs, tree rhs)
{
/* If this is the "or" of two comparisons, we can do something if
the comparisons are NE_EXPR. If this is the "and", we can do something
tree lntype, rntype, result;
HOST_WIDE_INT first_bit, end_bit;
int volatilep;
- tree orig_lhs = lhs, orig_rhs = rhs;
- enum tree_code orig_code = code;
/* Start by getting the comparison codes. Fail if anything is volatile.
If one operand is a BIT_AND_EXPR with the constant one, treat it as if
/* If the RHS can be evaluated unconditionally and its operands are
simple, it wins to evaluate the RHS unconditionally on machines
with expensive branches. In this case, this isn't a comparison
- that can be merged. Avoid doing this if the RHS is a floating-point
- comparison since those can trap. */
+ that can be merged. */
if (BRANCH_COST (optimize_function_for_speed_p (cfun),
false) >= 2
build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
ll_arg, rl_arg),
build_int_cst (TREE_TYPE (ll_arg), 0));
-
- if (LOGICAL_OP_NON_SHORT_CIRCUIT)
- {
- if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
- return build2_loc (loc, code, truth_type, lhs, rhs);
- return NULL_TREE;
- }
}
/* See if the comparisons can be merged. Then get all the parameters for
lhs is another similar operation, try to merge its rhs with our
rhs. Then try to merge our lhs and rhs. */
if (TREE_CODE (arg0) == code
- && 0 != (tem = fold_truthop (loc, code, type,
- TREE_OPERAND (arg0, 1), arg1)))
+ && 0 != (tem = fold_truth_andor_1 (loc, code, type,
+ TREE_OPERAND (arg0, 1), arg1)))
return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
- if ((tem = fold_truthop (loc, code, type, arg0, arg1)) != 0)
+ if ((tem = fold_truth_andor_1 (loc, code, type, arg0, arg1)) != 0)
return tem;
+ if ((BRANCH_COST (optimize_function_for_speed_p (cfun),
+ false) >= 2)
+ && LOGICAL_OP_NON_SHORT_CIRCUIT
+ && (code == TRUTH_AND_EXPR
+ || code == TRUTH_ANDIF_EXPR
+ || code == TRUTH_OR_EXPR
+ || code == TRUTH_ORIF_EXPR))
+ {
+ enum tree_code ncode, icode;
+
+ ncode = (code == TRUTH_ANDIF_EXPR || code == TRUTH_AND_EXPR)
+ ? TRUTH_AND_EXPR : TRUTH_OR_EXPR;
+ icode = ncode == TRUTH_AND_EXPR ? TRUTH_ANDIF_EXPR : TRUTH_ORIF_EXPR;
+
+ /* Transform ((A AND-IF B) AND[-IF] C) into (A AND-IF (B AND C)),
+ or ((A OR-IF B) OR[-IF] C) into (A OR-IF (B OR C))
+ We don't want to pack more than two leafs to a non-IF AND/OR
+ expression.
+ If tree-code of left-hand operand isn't an AND/OR-IF code and not
+ equal to IF-CODE, then we don't want to add right-hand operand.
+ If the inner right-hand side of left-hand operand has
+ side-effects, or isn't simple, then we can't add to it,
+ as otherwise we might destroy if-sequence. */
+ if (TREE_CODE (arg0) == icode
+ && simple_operand_p_2 (arg1)
+ /* Needed for sequence points to handle trappings, and
+ side-effects. */
+ && simple_operand_p_2 (TREE_OPERAND (arg0, 1)))
+ {
+ tem = fold_build2_loc (loc, ncode, type, TREE_OPERAND (arg0, 1),
+ arg1);
+ return fold_build2_loc (loc, icode, type, TREE_OPERAND (arg0, 0),
+ tem);
+ }
+ /* Same as abouve but for (A AND[-IF] (B AND-IF C)) -> ((A AND B) AND-IF C),
+ or (A OR[-IF] (B OR-IF C) -> ((A OR B) OR-IF C). */
+ else if (TREE_CODE (arg1) == icode
+ && simple_operand_p_2 (arg0)
+ /* Needed for sequence points to handle trappings, and
+ side-effects. */
+ && simple_operand_p_2 (TREE_OPERAND (arg1, 0)))
+ {
+ tem = fold_build2_loc (loc, ncode, type,
+ arg0, TREE_OPERAND (arg1, 0));
+ return fold_build2_loc (loc, icode, type, tem,
+ TREE_OPERAND (arg1, 1));
+ }
+ /* Transform (A AND-IF B) into (A AND B), or (A OR-IF B)
+ into (A OR B).
+ For sequence point consistancy, we need to check for trapping,
+ and side-effects. */
+ else if (code == icode && simple_operand_p_2 (arg0)
+ && simple_operand_p_2 (arg1))
+ return fold_build2_loc (loc, ncode, type, arg0, arg1);
+ }
+
return NULL_TREE;
}
projects / platform / upstream / gcc.git / commitdiff