/* Fold a constant sub-tree into a single node for C-compiler
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
Free Software Foundation, Inc.
This file is part of GCC.
static tree const_binop (enum tree_code, tree, tree, int);
static enum comparison_code comparison_to_compcode (enum tree_code);
static enum tree_code compcode_to_comparison (enum comparison_code);
-static tree combine_comparisons (enum tree_code, enum tree_code,
- enum tree_code, tree, tree, tree);
static int operand_equal_for_comparison_p (tree, tree, tree);
static int twoval_comparison_p (tree, tree *, tree *, int *);
static tree eval_subst (tree, tree, tree, tree, tree);
static tree fold_negate_const (tree, tree);
static tree fold_not_const (tree, tree);
static tree fold_relational_const (enum tree_code, tree, tree, tree);
+static tree fold_convert_const (enum tree_code, tree, tree);
/* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
of type CODE and returns the quotient.
Otherwise returns NULL_TREE. */
-static tree
+tree
div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
{
unsigned HOST_WIDE_INT int1l, int2l;
t = build_fixed (type, result);
/* Propagate overflow flags. */
if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
- {
- TREE_OVERFLOW (t) = 1;
- TREE_CONSTANT_OVERFLOW (t) = 1;
- }
- else if (TREE_CONSTANT_OVERFLOW (arg1) | TREE_CONSTANT_OVERFLOW (arg2))
- TREE_CONSTANT_OVERFLOW (t) = 1;
+ TREE_OVERFLOW (t) = 1;
return t;
}
return build_complex (type, real, imag);
}
+ if (TREE_CODE (arg1) == VECTOR_CST)
+ {
+ tree type = TREE_TYPE(arg1);
+ int count = TYPE_VECTOR_SUBPARTS (type), i;
+ tree elements1, elements2, list = NULL_TREE;
+
+ if(TREE_CODE(arg2) != VECTOR_CST)
+ return NULL_TREE;
+
+ elements1 = TREE_VECTOR_CST_ELTS (arg1);
+ elements2 = TREE_VECTOR_CST_ELTS (arg2);
+
+ for (i = 0; i < count; i++)
+ {
+ tree elem1, elem2, elem;
+
+ /* The trailing elements can be empty and should be treated as 0 */
+ if(!elements1)
+ elem1 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
+ else
+ {
+ elem1 = TREE_VALUE(elements1);
+ elements1 = TREE_CHAIN (elements1);
+ }
+
+ if(!elements2)
+ elem2 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
+ else
+ {
+ elem2 = TREE_VALUE(elements2);
+ elements2 = TREE_CHAIN (elements2);
+ }
+
+ elem = const_binop (code, elem1, elem2, notrunc);
+
+ /* It is possible that const_binop cannot handle the given
+ code and return NULL_TREE */
+ if(elem == NULL_TREE)
+ return NULL_TREE;
+
+ list = tree_cons (NULL_TREE, elem, list);
+ }
+ return build_vector(type, nreverse(list));
+ }
return NULL_TREE;
}
t = build_real (type, value);
TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
- TREE_CONSTANT_OVERFLOW (t)
- = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1);
return t;
}
/* Propagate overflow flags. */
if (overflow_p | TREE_OVERFLOW (arg1))
- {
- TREE_OVERFLOW (t) = 1;
- TREE_CONSTANT_OVERFLOW (t) = 1;
- }
- else if (TREE_CONSTANT_OVERFLOW (arg1))
- TREE_CONSTANT_OVERFLOW (t) = 1;
+ TREE_OVERFLOW (t) = 1;
return t;
}
/* Propagate overflow flags. */
if (overflow_p | TREE_OVERFLOW (arg1))
- {
- TREE_OVERFLOW (t) = 1;
- TREE_CONSTANT_OVERFLOW (t) = 1;
- }
- else if (TREE_CONSTANT_OVERFLOW (arg1))
- TREE_CONSTANT_OVERFLOW (t) = 1;
+ TREE_OVERFLOW (t) = 1;
return t;
}
/* Propagate overflow flags. */
if (overflow_p | TREE_OVERFLOW (arg1))
- {
- TREE_OVERFLOW (t) = 1;
- TREE_CONSTANT_OVERFLOW (t) = 1;
- }
- else if (TREE_CONSTANT_OVERFLOW (arg1))
- TREE_CONSTANT_OVERFLOW (t) = 1;
+ TREE_OVERFLOW (t) = 1;
return t;
}
static tree
build_range_check (tree type, tree exp, int in_p, tree low, tree high)
{
- tree etype = TREE_TYPE (exp);
- tree value;
+ tree etype = TREE_TYPE (exp), value;
+ enum tree_code code;
#ifdef HAVE_canonicalize_funcptr_for_compare
/* Disable this optimization for function pointer expressions
/* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
This requires wrap-around arithmetics for the type of the expression. */
- switch (TREE_CODE (etype))
+ code = TREE_CODE (etype);
+ switch (code)
{
case INTEGER_TYPE:
+ case ENUMERAL_TYPE:
+ case BOOLEAN_TYPE:
/* There is no requirement that LOW be within the range of ETYPE
if the latter is a subtype. It must, however, be within the base
type of ETYPE. So be sure we do the subtraction in that type. */
- if (TREE_TYPE (etype))
- etype = TREE_TYPE (etype);
- break;
+ if (code == INTEGER_TYPE && TREE_TYPE (etype))
+ {
+ etype = TREE_TYPE (etype);
+ /* But not in an enumeral or boolean type though. */
+ code = TREE_CODE (etype);
+ }
- case ENUMERAL_TYPE:
- case BOOLEAN_TYPE:
- etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
- TYPE_UNSIGNED (etype));
+ if (code != INTEGER_TYPE)
+ etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
+ TYPE_UNSIGNED (etype));
break;
default:
else
maybe_same = arg11;
- if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0)
+ if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0
+ /* The remainder should not be a constant, otherwise we
+ end up folding i * 4 + 2 to (i * 2 + 1) * 2 which has
+ increased the number of multiplications necessary. */
+ && TREE_CODE (arg10) != INTEGER_CST)
{
alt0 = fold_build2 (MULT_EXPR, TREE_TYPE (arg00), arg00,
build_int_cst (TREE_TYPE (arg00),
}
/* Build an expression for the address of T. Folds away INDIRECT_REF
- to avoid confusing the gimplify process. When IN_FOLD is true
- avoid modifications of T. */
+ to avoid confusing the gimplify process. */
-static tree
-build_fold_addr_expr_with_type_1 (tree t, tree ptrtype, bool in_fold)
+tree
+build_fold_addr_expr_with_type (tree t, tree ptrtype)
{
/* The size of the object is not relevant when talking about its address. */
if (TREE_CODE (t) == WITH_SIZE_EXPR)
if (TREE_TYPE (t) != ptrtype)
t = build1 (NOP_EXPR, ptrtype, t);
}
- else if (!in_fold)
- {
- tree base = t;
-
- while (handled_component_p (base))
- base = TREE_OPERAND (base, 0);
-
- if (DECL_P (base))
- TREE_ADDRESSABLE (base) = 1;
-
- t = build1 (ADDR_EXPR, ptrtype, t);
- }
else
t = build1 (ADDR_EXPR, ptrtype, t);
return t;
}
-/* Build an expression for the address of T with type PTRTYPE. This
- function modifies the input parameter 'T' by sometimes setting the
- TREE_ADDRESSABLE flag. */
-
-tree
-build_fold_addr_expr_with_type (tree t, tree ptrtype)
-{
- return build_fold_addr_expr_with_type_1 (t, ptrtype, false);
-}
-
-/* Build an expression for the address of T. This function modifies
- the input parameter 'T' by sometimes setting the TREE_ADDRESSABLE
- flag. When called from fold functions, use fold_addr_expr instead. */
+/* Build an expression for the address of T. */
tree
build_fold_addr_expr (tree t)
{
- return build_fold_addr_expr_with_type_1 (t,
- build_pointer_type (TREE_TYPE (t)),
- false);
-}
-
-/* Same as build_fold_addr_expr, builds an expression for the address
- of T, but avoids touching the input node 't'. Fold functions
- should use this version. */
-
-static tree
-fold_addr_expr (tree t)
-{
tree ptrtype = build_pointer_type (TREE_TYPE (t));
- return build_fold_addr_expr_with_type_1 (t, ptrtype, true);
+ return build_fold_addr_expr_with_type (t, ptrtype);
}
/* Fold a unary expression of code CODE and type TYPE with operand
&& inter_prec >= final_prec)
return fold_build1 (code, type, TREE_OPERAND (op0, 0));
- /* Likewise, if the intermediate and final types are either both
- float or both integer, we don't need the middle conversion if
- it is wider than the final type and doesn't change the signedness
- (for integers). Avoid this if the final type is a pointer
- since then we sometimes need the inner conversion. Likewise if
- the outer has a precision not equal to the size of its mode. */
+ /* Likewise, if the intermediate and initial types are either both
+ float or both integer, we don't need the middle conversion if the
+ former is wider than the latter and doesn't change the signedness
+ (for integers). Avoid this if the final type is a pointer since
+ then we sometimes need the middle conversion. Likewise if the
+ final type has a precision not equal to the size of its mode. */
if (((inter_int && inside_int)
|| (inter_float && inside_float)
|| (inter_vec && inside_vec))
if (! offset && bitpos == 0
&& TYPE_MAIN_VARIANT (TREE_TYPE (type))
== TYPE_MAIN_VARIANT (TREE_TYPE (base)))
- return fold_convert (type, fold_addr_expr (base));
+ return fold_convert (type, build_fold_addr_expr (base));
}
if (TREE_CODE (op0) == MODIFY_EXPR
} /* switch (code) */
}
+
+/* If the operation was a conversion do _not_ mark a resulting constant
+ with TREE_OVERFLOW if the original constant was not. These conversions
+ have implementation defined behavior and retaining the TREE_OVERFLOW
+ flag here would confuse later passes such as VRP. */
+tree
+fold_unary_ignore_overflow (enum tree_code code, tree type, tree op0)
+{
+ tree res = fold_unary (code, type, op0);
+ if (res
+ && TREE_CODE (res) == INTEGER_CST
+ && TREE_CODE (op0) == INTEGER_CST
+ && CONVERT_EXPR_CODE_P (code))
+ TREE_OVERFLOW (res) = TREE_OVERFLOW (op0);
+
+ return res;
+}
+
/* Fold a binary expression of code CODE and type TYPE with operands
OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
Return the folded expression if folding is successful. Otherwise,
&& operand_equal_p (offset0, offset1, 0))))
{
if (indirect_base0)
- base0 = fold_addr_expr (base0);
+ base0 = build_fold_addr_expr (base0);
if (indirect_base1)
- base1 = fold_addr_expr (base1);
+ base1 = build_fold_addr_expr (base1);
return fold_build2 (code, type, base0, base1);
}
}
}
/* Fold comparisons against infinity. */
- if (REAL_VALUE_ISINF (cst))
+ if (REAL_VALUE_ISINF (cst)
+ && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))))
{
tem = fold_inf_compare (code, type, arg0, arg1);
if (tem != NULL_TREE)
0 <= N < M as is common. In general, the precise value of P is unknown.
M is chosen as large as possible such that constant N can be determined.
- Returns M and sets *RESIDUE to N. */
+ Returns M and sets *RESIDUE to N.
+
+ If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into
+ account. This is not always possible due to PR 35705.
+ */
static unsigned HOST_WIDE_INT
-get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue)
+get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue,
+ bool allow_func_align)
{
enum tree_code code;
}
}
- if (DECL_P (expr) && TREE_CODE (expr) != FUNCTION_DECL)
+ if (DECL_P (expr)
+ && (allow_func_align || TREE_CODE (expr) != FUNCTION_DECL))
return DECL_ALIGN_UNIT (expr);
}
else if (code == POINTER_PLUS_EXPR)
op0 = TREE_OPERAND (expr, 0);
STRIP_NOPS (op0);
- modulus = get_pointer_modulus_and_residue (op0, residue);
+ modulus = get_pointer_modulus_and_residue (op0, residue,
+ allow_func_align);
op1 = TREE_OPERAND (expr, 1);
STRIP_NOPS (op1);
return NULL_TREE;
case PLUS_EXPR:
- /* PTR + INT -> (INT)(PTR p+ INT) */
- if (POINTER_TYPE_P (TREE_TYPE (arg0))
- && INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
- return fold_convert (type, fold_build2 (POINTER_PLUS_EXPR,
- TREE_TYPE (arg0),
- arg0,
- fold_convert (sizetype, arg1)));
- /* INT + PTR -> (INT)(PTR p+ INT) */
- if (POINTER_TYPE_P (TREE_TYPE (arg1))
- && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
- return fold_convert (type, fold_build2 (POINTER_PLUS_EXPR,
- TREE_TYPE (arg1),
- arg1,
- fold_convert (sizetype, arg0)));
/* A + (-B) -> A - B */
if (TREE_CODE (arg1) == NEGATE_EXPR)
return fold_build2 (MINUS_EXPR, type,
unsigned HOST_WIDE_INT modulus, residue;
unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
- modulus = get_pointer_modulus_and_residue (arg0, &residue);
+ modulus = get_pointer_modulus_and_residue (arg0, &residue,
+ integer_onep (arg1));
/* This works because modulus is a power of 2. If this weren't the
case, we'd have to replace it by its greatest power-of-2
fold_convert (TREE_TYPE (arg0), arg1),
TREE_OPERAND (arg0, 1)));
- /* Transform comparisons of the form X +- C CMP X. */
- if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+ /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
+ if ((TREE_CODE (arg0) == PLUS_EXPR
+ || TREE_CODE (arg0) == POINTER_PLUS_EXPR
+ || TREE_CODE (arg0) == MINUS_EXPR)
&& operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
&& (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
|| POINTER_TYPE_P (TREE_TYPE (arg0))))
{
- tree cst = TREE_OPERAND (arg0, 1);
+ tree val = TREE_OPERAND (arg0, 1);
+ return omit_two_operands (type,
+ fold_build2 (code, type,
+ val,
+ build_int_cst (TREE_TYPE (val),
+ 0)),
+ TREE_OPERAND (arg0, 0), arg1);
+ }
- if (code == EQ_EXPR
- && !integer_zerop (cst))
- return omit_two_operands (type, boolean_false_node,
- TREE_OPERAND (arg0, 0), arg1);
- else
- return omit_two_operands (type, boolean_true_node,
- TREE_OPERAND (arg0, 0), arg1);
+ /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
+ if (TREE_CODE (arg0) == MINUS_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)
+ && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
+ {
+ return omit_two_operands (type,
+ code == NE_EXPR
+ ? boolean_true_node : boolean_false_node,
+ TREE_OPERAND (arg0, 1), arg1);
}
/* If we have X - Y == 0, we can convert that to X == Y and similarly
if (!base)
return false;
- /* Weak declarations may link to NULL. */
- if (VAR_OR_FUNCTION_DECL_P (base))
- return !DECL_WEAK (base);
+ /* Weak declarations may link to NULL. Other things may also be NULL
+ so protect with -fdelete-null-pointer-checks; but not variables
+ allocated on the stack. */
+ if (DECL_P (base)
+ && (flag_delete_null_pointer_checks
+ || (TREE_CODE (base) == VAR_DECL && !TREE_STATIC (base))))
+ return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
/* Constants are never weak. */
if (CONSTANT_CLASS_P (base))
t = build_fixed (type, f);
/* Propagate overflow flags. */
if (overflow_p | TREE_OVERFLOW (arg0))
- {
- TREE_OVERFLOW (t) = 1;
- TREE_CONSTANT_OVERFLOW (t) = 1;
- }
- else if (TREE_CONSTANT_OVERFLOW (arg0))
- TREE_CONSTANT_OVERFLOW (t) = 1;
+ TREE_OVERFLOW (t) = 1;
break;
}
core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
poffset, &mode, &unsignedp, &volatilep,
false);
- core = fold_addr_expr (core);
+ core = build_fold_addr_expr (core);
}
else
{
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