* *
* C Implementation File *
* *
- * Copyright (C) 1992-2009, Free Software Foundation, Inc. *
+ * Copyright (C) 1992-2010, Free Software Foundation, Inc. *
* *
* GNAT is free software; you can redistribute it and/or modify it under *
* terms of the GNU General Public License as published by the Free Soft- *
#include "ggc.h"
#include "flags.h"
#include "output.h"
+#include "tree-inline.h"
#include "ada.h"
#include "types.h"
#include "gigi.h"
static tree find_common_type (tree, tree);
-static bool contains_save_expr_p (tree);
-static tree contains_null_expr (tree);
static tree compare_arrays (tree, tree, tree);
static tree nonbinary_modular_operation (enum tree_code, tree, tree, tree);
static tree build_simple_component_ref (tree, tree, tree, bool);
\f
-/* Prepare expr to be an argument of a TRUTH_NOT_EXPR or other logical
- operation.
-
- This preparation consists of taking the ordinary representation of
- an expression expr and producing a valid tree boolean expression
- describing whether expr is nonzero. We could simply always do
-
- build_binary_op (NE_EXPR, expr, integer_zero_node, 1),
-
- but we optimize comparisons, &&, ||, and !.
-
- The resulting type should always be the same as the input type.
- This function is simpler than the corresponding C version since
- the only possible operands will be things of Boolean type. */
-
-tree
-gnat_truthvalue_conversion (tree expr)
-{
- tree type = TREE_TYPE (expr);
-
- switch (TREE_CODE (expr))
- {
- case EQ_EXPR: case NE_EXPR: case LE_EXPR: case GE_EXPR:
- case LT_EXPR: case GT_EXPR:
- case TRUTH_ANDIF_EXPR:
- case TRUTH_ORIF_EXPR:
- case TRUTH_AND_EXPR:
- case TRUTH_OR_EXPR:
- case TRUTH_XOR_EXPR:
- case ERROR_MARK:
- return expr;
-
- case INTEGER_CST:
- return (integer_zerop (expr)
- ? build_int_cst (type, 0)
- : build_int_cst (type, 1));
-
- case REAL_CST:
- return (real_zerop (expr)
- ? fold_convert (type, integer_zero_node)
- : fold_convert (type, integer_one_node));
-
- case COND_EXPR:
- /* Distribute the conversion into the arms of a COND_EXPR. */
- {
- tree arg1 = gnat_truthvalue_conversion (TREE_OPERAND (expr, 1));
- tree arg2 = gnat_truthvalue_conversion (TREE_OPERAND (expr, 2));
- return fold_build3 (COND_EXPR, type, TREE_OPERAND (expr, 0),
- arg1, arg2);
- }
-
- default:
- return build_binary_op (NE_EXPR, type, expr,
- fold_convert (type, integer_zero_node));
- }
-}
-\f
/* Return the base type of TYPE. */
tree
this_alignment = expr_align (TREE_OPERAND (exp, 0));
break;
+ case CALL_EXPR:
+ {
+ tree t = maybe_inline_call_in_expr (exp);
+ if (t)
+ return known_alignment (t);
+ }
+
+ /* Fall through... */
+
default:
/* For other pointer expressions, we assume that the pointed-to object
is at least as aligned as the pointed-to type. Beware that we can
return NULL_TREE;
}
\f
-/* See if EXP contains a SAVE_EXPR in a position where we would
- normally put it.
-
- ??? This is a real kludge, but is probably the best approach short
- of some very general solution. */
+/* Return an expression tree representing an equality comparison of A1 and A2,
+ two objects of type ARRAY_TYPE. The result should be of type RESULT_TYPE.
-static bool
-contains_save_expr_p (tree exp)
-{
- switch (TREE_CODE (exp))
- {
- case SAVE_EXPR:
- return true;
-
- case ADDR_EXPR: case INDIRECT_REF:
- case COMPONENT_REF:
- CASE_CONVERT: case VIEW_CONVERT_EXPR:
- return contains_save_expr_p (TREE_OPERAND (exp, 0));
-
- case CONSTRUCTOR:
- {
- tree value;
- unsigned HOST_WIDE_INT ix;
-
- FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), ix, value)
- if (contains_save_expr_p (value))
- return true;
- return false;
- }
-
- default:
- return false;
- }
-}
-\f
-/* See if EXP contains a NULL_EXPR in an expression we use for sizes. Return
- it if so. This is used to detect types whose sizes involve computations
- that are known to raise Constraint_Error. */
-
-static tree
-contains_null_expr (tree exp)
-{
- tree tem;
-
- if (TREE_CODE (exp) == NULL_EXPR)
- return exp;
-
- switch (TREE_CODE_CLASS (TREE_CODE (exp)))
- {
- case tcc_unary:
- return contains_null_expr (TREE_OPERAND (exp, 0));
-
- case tcc_comparison:
- case tcc_binary:
- tem = contains_null_expr (TREE_OPERAND (exp, 0));
- if (tem)
- return tem;
-
- return contains_null_expr (TREE_OPERAND (exp, 1));
-
- case tcc_expression:
- switch (TREE_CODE (exp))
- {
- case SAVE_EXPR:
- return contains_null_expr (TREE_OPERAND (exp, 0));
-
- case COND_EXPR:
- tem = contains_null_expr (TREE_OPERAND (exp, 0));
- if (tem)
- return tem;
-
- tem = contains_null_expr (TREE_OPERAND (exp, 1));
- if (tem)
- return tem;
-
- return contains_null_expr (TREE_OPERAND (exp, 2));
-
- default:
- return 0;
- }
-
- default:
- return 0;
- }
-}
-\f
-/* Return an expression tree representing an equality comparison of
- A1 and A2, two objects of ARRAY_TYPE. The returned expression should
- be of type RESULT_TYPE
-
- Two arrays are equal in one of two ways: (1) if both have zero length
- in some dimension (not necessarily the same dimension) or (2) if the
- lengths in each dimension are equal and the data is equal. We perform the
- length tests in as efficient a manner as possible. */
+ Two arrays are equal in one of two ways: (1) if both have zero length in
+ some dimension (not necessarily the same dimension) or (2) if the lengths
+ in each dimension are equal and the data is equal. We perform the length
+ tests in as efficient a manner as possible. */
static tree
compare_arrays (tree result_type, tree a1, tree a2)
tree result = convert (result_type, integer_one_node);
tree a1_is_null = convert (result_type, integer_zero_node);
tree a2_is_null = convert (result_type, integer_zero_node);
+ bool a1_side_effects_p = TREE_SIDE_EFFECTS (a1);
+ bool a2_side_effects_p = TREE_SIDE_EFFECTS (a2);
bool length_zero_p = false;
+ /* If either operand has side-effects, they have to be evaluated only once
+ in spite of the multiple references to the operand in the comparison. */
+ if (a1_side_effects_p)
+ a1 = gnat_protect_expr (a1);
+
+ if (a2_side_effects_p)
+ a2 = gnat_protect_expr (a2);
+
/* Process each dimension separately and compare the lengths. If any
dimension has a size known to be zero, set SIZE_ZERO_P to 1 to
suppress the comparison of the data. */
tree bt = get_base_type (TREE_TYPE (lb1));
tree length1 = fold_build2 (MINUS_EXPR, bt, ub1, lb1);
tree length2 = fold_build2 (MINUS_EXPR, bt, ub2, lb2);
- tree nbt;
- tree tem;
tree comparison, this_a1_is_null, this_a2_is_null;
+ tree nbt, tem;
+ bool btem;
/* If the length of the first array is a constant, swap our operands
unless the length of the second array is the constant zero.
tem = ub1, ub1 = ub2, ub2 = tem;
tem = length1, length1 = length2, length2 = tem;
tem = a1_is_null, a1_is_null = a2_is_null, a2_is_null = tem;
+ btem = a1_side_effects_p, a1_side_effects_p = a2_side_effects_p,
+ a2_side_effects_p = btem;
}
/* If the length of this dimension in the second array is the constant
tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
if (type)
- a1 = convert (type, a1), a2 = convert (type, a2);
+ {
+ a1 = convert (type, a1),
+ a2 = convert (type, a2);
+ }
result = build_binary_op (TRUTH_ANDIF_EXPR, result_type, result,
fold_build2 (EQ_EXPR, result_type, a1, a2));
-
}
/* The result is also true if both sizes are zero. */
a1_is_null, a2_is_null),
result);
- /* If either operand contains SAVE_EXPRs, they have to be evaluated before
- starting the comparison above since the place it would be otherwise
- evaluated would be wrong. */
-
- if (contains_save_expr_p (a1))
+ /* If either operand has side-effects, they have to be evaluated before
+ starting the comparison above since the place they would be otherwise
+ evaluated could be wrong. */
+ if (a1_side_effects_p)
result = build2 (COMPOUND_EXPR, result_type, a1, result);
- if (contains_save_expr_p (a2))
+ if (a2_side_effects_p)
result = build2 (COMPOUND_EXPR, result_type, a2, result);
return result;
/* For subtraction, add the modulus back if we are negative. */
else if (op_code == MINUS_EXPR)
{
- result = save_expr (result);
+ result = gnat_protect_expr (result);
result = fold_build3 (COND_EXPR, op_type,
fold_build2 (LT_EXPR, integer_type_node, result,
convert (op_type, integer_zero_node)),
/* For the other operations, subtract the modulus if we are >= it. */
else
{
- result = save_expr (result);
+ result = gnat_protect_expr (result);
result = fold_build3 (COND_EXPR, op_type,
fold_build2 (GE_EXPR, integer_type_node,
result, modulus),
switch (op_code)
{
+ case INIT_EXPR:
case MODIFY_EXPR:
/* If there were integral or pointer conversions on the LHS, remove
them; we'll be putting them back below if needed. Likewise for
/* If we are copying between padded objects with compatible types, use
the padded view of the objects, this is very likely more efficient.
- Likewise for a padded that is assigned a constructor, in order to
- avoid putting a VIEW_CONVERT_EXPR on the LHS. But don't do this if
- we wouldn't have actually copied anything. */
- else if (TREE_CODE (left_type) == RECORD_TYPE
- && TYPE_IS_PADDING_P (left_type)
+ Likewise for a padded object that is assigned a constructor, if we
+ can convert the constructor to the inner type, to avoid putting a
+ VIEW_CONVERT_EXPR on the LHS. But don't do so if we wouldn't have
+ actually copied anything. */
+ else if (TYPE_IS_PADDING_P (left_type)
&& TREE_CONSTANT (TYPE_SIZE (left_type))
&& ((TREE_CODE (right_operand) == COMPONENT_REF
- && TREE_CODE (TREE_TYPE (TREE_OPERAND (right_operand, 0)))
- == RECORD_TYPE
&& TYPE_IS_PADDING_P
(TREE_TYPE (TREE_OPERAND (right_operand, 0)))
&& gnat_types_compatible_p
- (left_type,
- TREE_TYPE (TREE_OPERAND (right_operand, 0))))
- || TREE_CODE (right_operand) == CONSTRUCTOR)
+ (left_type,
+ TREE_TYPE (TREE_OPERAND (right_operand, 0))))
+ || (TREE_CODE (right_operand) == CONSTRUCTOR
+ && !CONTAINS_PLACEHOLDER_P
+ (DECL_SIZE (TYPE_FIELDS (left_type)))))
&& !integer_zerop (TYPE_SIZE (right_type)))
operation_type = left_type;
left_type = TREE_TYPE (left_operand);
}
+ /* For a range, make sure the element type is consistent. */
+ if (op_code == ARRAY_RANGE_REF
+ && TREE_TYPE (operation_type) != TREE_TYPE (left_type))
+ operation_type = build_array_type (TREE_TYPE (left_type),
+ TYPE_DOMAIN (operation_type));
+
/* Then convert the right operand to its base type. This will prevent
unneeded sign conversions when sizetype is wider than integer. */
right_operand = convert (right_base_type, right_operand);
return result;
}
- /* Otherwise, the base types must be the same unless the objects are
- fat pointers or records. If we have records, use the best type and
- convert both operands to that type. */
+ /* Otherwise, the base types must be the same, unless they are both fat
+ pointer types or record types. In the latter case, use the best type
+ and convert both operands to that type. */
if (left_base_type != right_base_type)
{
- if (TYPE_FAT_POINTER_P (left_base_type)
- && TYPE_FAT_POINTER_P (right_base_type)
- && TYPE_MAIN_VARIANT (left_base_type)
- == TYPE_MAIN_VARIANT (right_base_type))
- best_type = left_base_type;
+ if (TYPE_IS_FAT_POINTER_P (left_base_type)
+ && TYPE_IS_FAT_POINTER_P (right_base_type))
+ {
+ gcc_assert (TYPE_MAIN_VARIANT (left_base_type)
+ == TYPE_MAIN_VARIANT (right_base_type));
+ best_type = left_base_type;
+ }
+
else if (TREE_CODE (left_base_type) == RECORD_TYPE
&& TREE_CODE (right_base_type) == RECORD_TYPE)
{
- /* The only way these are permitted to be the same is if both
- types have the same name. In that case, one of them must
- not be self-referential. Use that one as the best type.
- Even better is if one is of fixed size. */
+ /* The only way this is permitted is if both types have the same
+ name. In that case, one of them must not be self-referential.
+ Use it as the best type. Even better with a fixed size. */
gcc_assert (TYPE_NAME (left_base_type)
- && (TYPE_NAME (left_base_type)
- == TYPE_NAME (right_base_type)));
+ && TYPE_NAME (left_base_type)
+ == TYPE_NAME (right_base_type));
if (TREE_CONSTANT (TYPE_SIZE (left_base_type)))
best_type = left_base_type;
else
gcc_unreachable ();
}
+
else
gcc_unreachable ();
left_operand = convert (best_type, left_operand);
right_operand = convert (best_type, right_operand);
}
-
- /* If we are comparing a fat pointer against zero, we need to
- just compare the data pointer. */
- else if (TYPE_FAT_POINTER_P (left_base_type)
- && TREE_CODE (right_operand) == CONSTRUCTOR
- && integer_zerop (VEC_index (constructor_elt,
- CONSTRUCTOR_ELTS (right_operand),
- 0)
- ->value))
- {
- right_operand = build_component_ref (left_operand, NULL_TREE,
- TYPE_FIELDS (left_base_type),
- false);
- left_operand = convert (TREE_TYPE (right_operand),
- integer_zero_node);
- }
else
{
left_operand = convert (left_base_type, left_operand);
right_operand = convert (right_base_type, right_operand);
}
+ /* If we are comparing a fat pointer against zero, we just need to
+ compare the data pointer. */
+ if (TYPE_IS_FAT_POINTER_P (left_base_type)
+ && TREE_CODE (right_operand) == CONSTRUCTOR
+ && integer_zerop (VEC_index (constructor_elt,
+ CONSTRUCTOR_ELTS (right_operand),
+ 0)->value))
+ {
+ left_operand
+ = build_component_ref (left_operand, NULL_TREE,
+ TYPE_FIELDS (left_base_type), false);
+ right_operand
+ = convert (TREE_TYPE (left_operand), integer_zero_node);
+ }
+
modulus = NULL_TREE;
break;
left_operand = convert (operation_type, left_operand);
break;
- case TRUTH_ANDIF_EXPR:
- case TRUTH_ORIF_EXPR:
- case TRUTH_AND_EXPR:
- case TRUTH_OR_EXPR:
- case TRUTH_XOR_EXPR:
- left_operand = gnat_truthvalue_conversion (left_operand);
- right_operand = gnat_truthvalue_conversion (right_operand);
- goto common;
-
case BIT_AND_EXPR:
case BIT_IOR_EXPR:
case BIT_XOR_EXPR:
case TRUTH_NOT_EXPR:
gcc_assert (result_type == base_type);
- result = invert_truthvalue (gnat_truthvalue_conversion (operand));
+ result = invert_truthvalue (operand);
break;
case ATTR_ADDR_EXPR:
TREE_TYPE (result) = type = build_pointer_type (type);
break;
+ case COMPOUND_EXPR:
+ /* Fold a compound expression if it has unconstrained array type
+ since the middle-end cannot handle it. But we don't it in the
+ general case because it may introduce aliasing issues if the
+ first operand is an indirect assignment and the second operand
+ the corresponding address, e.g. for an allocator. */
+ if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
+ {
+ result = build_unary_op (ADDR_EXPR, result_type,
+ TREE_OPERAND (operand, 1));
+ result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
+ TREE_OPERAND (operand, 0), result);
+ break;
+ }
+ goto common;
+
case ARRAY_REF:
case ARRAY_RANGE_REF:
case COMPONENT_REF:
/* If INNER is a padding type whose field has a self-referential
size, convert to that inner type. We know the offset is zero
and we need to have that type visible. */
- if (TREE_CODE (TREE_TYPE (inner)) == RECORD_TYPE
- && TYPE_IS_PADDING_P (TREE_TYPE (inner))
- && (CONTAINS_PLACEHOLDER_P
- (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
- (TREE_TYPE (inner)))))))
+ if (TYPE_IS_PADDING_P (TREE_TYPE (inner))
+ && CONTAINS_PLACEHOLDER_P
+ (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
+ (TREE_TYPE (inner))))))
inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
inner);
/* If this is just a constructor for a padded record, we can
just take the address of the single field and convert it to
a pointer to our type. */
- if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
+ if (TYPE_IS_PADDING_P (type))
{
- result = (VEC_index (constructor_elt,
- CONSTRUCTOR_ELTS (operand),
- 0)
- ->value);
-
+ result = VEC_index (constructor_elt,
+ CONSTRUCTOR_ELTS (operand),
+ 0)->value;
result = convert (build_pointer_type (TREE_TYPE (operand)),
build_unary_op (ADDR_EXPR, NULL_TREE, result));
break;
/* If we are taking the address of a padded record whose field is
contains a template, take the address of the template. */
- if (TREE_CODE (type) == RECORD_TYPE
- && TYPE_IS_PADDING_P (type)
+ if (TYPE_IS_PADDING_P (type)
&& TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
&& TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
{
make up an expression to do so. This will never survive to
the backend. If TYPE is a thin pointer, first convert the
operand to a fat pointer. */
- if (TYPE_THIN_POINTER_P (type)
+ if (TYPE_IS_THIN_POINTER_P (type)
&& TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
{
operand
type = TREE_TYPE (operand);
}
- if (TYPE_FAT_POINTER_P (type))
+ if (TYPE_IS_FAT_POINTER_P (type))
{
result = build1 (UNCONSTRAINED_ARRAY_REF,
TYPE_UNCONSTRAINED_ARRAY (type), operand);
- TREE_READONLY (result) = TREE_STATIC (result)
+ TREE_READONLY (result)
= TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
}
else if (TREE_CODE (operand) == ADDR_EXPR)
}
side_effects
- = (!TYPE_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
+ = (!TYPE_IS_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
break;
case NEGATE_EXPR:
true_operand = convert (result_type, true_operand);
false_operand = convert (result_type, false_operand);
- /* If the result type is unconstrained, take the address of the operands
- and then dereference our result. */
+ /* If the result type is unconstrained, take the address of the operands and
+ then dereference the result. Likewise if the result type is passed by
+ reference, but this is natively handled in the gimplifier. */
if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
|| CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
{
return result;
}
-/* Similar, but for RETURN_EXPR. If RESULT_DECL is non-zero, build
- a RETURN_EXPR around the assignment of RET_VAL to RESULT_DECL.
- If RESULT_DECL is zero, build a bare RETURN_EXPR. */
+/* Similar, but for RETURN_EXPR. If RET_VAL is non-null, build a RETURN_EXPR
+ around the assignment of RET_VAL to RET_OBJ. Otherwise just build a bare
+ RETURN_EXPR around RESULT_OBJ, which may be null in this case. */
tree
-build_return_expr (tree result_decl, tree ret_val)
+build_return_expr (tree ret_obj, tree ret_val)
{
tree result_expr;
- if (result_decl)
+ if (ret_val)
{
/* The gimplifier explicitly enforces the following invariant:
- RETURN_EXPR
- |
- MODIFY_EXPR
- / \
- / \
- RESULT_DECL ...
+ RETURN_EXPR
+ |
+ MODIFY_EXPR
+ / \
+ / \
+ RET_OBJ ...
- As a consequence, type-homogeneity dictates that we use the type
- of the RESULT_DECL as the operation type. */
-
- tree operation_type = TREE_TYPE (result_decl);
-
- /* Convert the right operand to the operation type. Note that
- it's the same transformation as in the MODIFY_EXPR case of
- build_binary_op with the additional guarantee that the type
- cannot involve a placeholder, since otherwise the function
- would use the "target pointer" return mechanism. */
+ As a consequence, type consistency dictates that we use the type
+ of the RET_OBJ as the operation type. */
+ tree operation_type = TREE_TYPE (ret_obj);
+ /* Convert the right operand to the operation type. Note that it's the
+ same transformation as in the MODIFY_EXPR case of build_binary_op,
+ with the assumption that the type cannot involve a placeholder. */
if (operation_type != TREE_TYPE (ret_val))
ret_val = convert (operation_type, ret_val);
- result_expr
- = build2 (MODIFY_EXPR, operation_type, result_decl, ret_val);
+ result_expr = build2 (MODIFY_EXPR, operation_type, ret_obj, ret_val);
}
else
- result_expr = NULL_TREE;
+ result_expr = ret_obj;
return build1 (RETURN_EXPR, void_type_node, result_expr);
}
if (TREE_SIDE_EFFECTS (val))
side_effects = true;
-
- /* Propagate an NULL_EXPR from the size of the type. We won't ever
- be executing the code we generate here in that case, but handle it
- specially to avoid the compiler blowing up. */
- if (TREE_CODE (type) == RECORD_TYPE
- && (result = contains_null_expr (DECL_SIZE (obj))) != NULL_TREE)
- return build1 (NULL_EXPR, type, TREE_OPERAND (result, 0));
}
/* For record types with constant components only, sort field list
tree new_field;
/* First loop thru normal components. */
-
for (new_field = TYPE_FIELDS (record_type); new_field;
new_field = TREE_CHAIN (new_field))
- if (field == new_field
- || DECL_ORIGINAL_FIELD (new_field) == field
- || new_field == DECL_ORIGINAL_FIELD (field)
- || (DECL_ORIGINAL_FIELD (field)
- && (DECL_ORIGINAL_FIELD (field)
- == DECL_ORIGINAL_FIELD (new_field))))
+ if (SAME_FIELD_P (field, new_field))
break;
/* Next, loop thru DECL_INTERNAL_P components if we haven't found
the component in the first search. Doing this search in 2 steps
is required to avoiding hidden homonymous fields in the
_Parent field. */
-
if (!new_field)
for (new_field = TYPE_FIELDS (record_type); new_field;
new_field = TREE_CHAIN (new_field))
{
/* Latch malloc's return value and get a pointer to the aligning field
first. */
- tree storage_ptr = save_expr (malloc_ptr);
+ tree storage_ptr = gnat_protect_expr (malloc_ptr);
tree aligning_record_addr
= convert (build_pointer_type (aligning_type), storage_ptr);
tree aligning_field
= build_component_ref (aligning_record, NULL_TREE,
- TYPE_FIELDS (aligning_type), 0);
+ TYPE_FIELDS (aligning_type), false);
tree aligning_field_addr
= build_unary_op (ADDR_EXPR, NULL_TREE, aligning_field);
tree storage_ptr_slot_addr
= build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
convert (ptr_void_type_node, aligning_field_addr),
- size_int (-POINTER_SIZE/BITS_PER_UNIT));
+ size_int (-(HOST_WIDE_INT) POINTER_SIZE
+ / BITS_PER_UNIT));
tree storage_ptr_slot
= build_unary_op (INDIRECT_REF, NULL_TREE,
= build_binary_op
(POINTER_PLUS_EXPR, ptr_void_type_node,
convert (ptr_void_type_node, data_ptr),
- size_int (-POINTER_SIZE/BITS_PER_UNIT));
+ size_int (-(HOST_WIDE_INT) POINTER_SIZE / BITS_PER_UNIT));
/* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
free_ptr
/* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
sizes of the object and its template. Allocate the whole thing and
fill in the parts that are known. */
- else if (TYPE_FAT_OR_THIN_POINTER_P (result_type))
+ else if (TYPE_IS_FAT_OR_THIN_POINTER_P (result_type))
{
tree storage_type
= build_unc_object_type_from_ptr (result_type, type,
storage = build_call_alloc_dealloc (NULL_TREE, size, storage_type,
gnat_proc, gnat_pool, gnat_node);
- storage = convert (storage_ptr_type, protect_multiple_eval (storage));
+ storage = convert (storage_ptr_type, gnat_protect_expr (storage));
- if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
+ if (TYPE_IS_PADDING_P (type))
{
type = TREE_TYPE (TYPE_FIELDS (type));
-
if (init)
init = convert (type, init);
}
build_component_ref
(build_unary_op (INDIRECT_REF, NULL_TREE,
convert (storage_ptr_type, storage)),
- NULL_TREE, TYPE_FIELDS (storage_type), 0),
+ NULL_TREE, TYPE_FIELDS (storage_type), false),
build_template (template_type, type, NULL_TREE)),
convert (result_type, convert (storage_ptr_type, storage)));
}
gnat_proc, gnat_pool,
gnat_node));
- /* If we have an initial value, put the new address into a SAVE_EXPR, assign
- the value, and return the address. Do this with a COMPOUND_EXPR. */
-
+ /* If we have an initial value, protect the new address, assign the value
+ and return the address with a COMPOUND_EXPR. */
if (init)
{
- result = save_expr (result);
+ result = gnat_protect_expr (result);
result
= build2 (COMPOUND_EXPR, TREE_TYPE (result),
build_binary_op
return gnat_build_constructor (record_type, nreverse (const_list));
}
-/* Indicate that we need to make the address of EXPR_NODE and it therefore
+/* Indicate that we need to take the address of T and that it therefore
should not be allocated in a register. Returns true if successful. */
bool
-gnat_mark_addressable (tree expr_node)
+gnat_mark_addressable (tree t)
{
- while (1)
- switch (TREE_CODE (expr_node))
+ while (true)
+ switch (TREE_CODE (t))
{
case ADDR_EXPR:
case COMPONENT_REF:
case VIEW_CONVERT_EXPR:
case NON_LVALUE_EXPR:
CASE_CONVERT:
- expr_node = TREE_OPERAND (expr_node, 0);
+ t = TREE_OPERAND (t, 0);
+ break;
+
+ case COMPOUND_EXPR:
+ t = TREE_OPERAND (t, 1);
break;
case CONSTRUCTOR:
- TREE_ADDRESSABLE (expr_node) = 1;
+ TREE_ADDRESSABLE (t) = 1;
return true;
case VAR_DECL:
case PARM_DECL:
case RESULT_DECL:
- TREE_ADDRESSABLE (expr_node) = 1;
+ TREE_ADDRESSABLE (t) = 1;
return true;
case FUNCTION_DECL:
- TREE_ADDRESSABLE (expr_node) = 1;
+ TREE_ADDRESSABLE (t) = 1;
return true;
case CONST_DECL:
- return (DECL_CONST_CORRESPONDING_VAR (expr_node)
- && (gnat_mark_addressable
- (DECL_CONST_CORRESPONDING_VAR (expr_node))));
+ return DECL_CONST_CORRESPONDING_VAR (t)
+ && gnat_mark_addressable (DECL_CONST_CORRESPONDING_VAR (t));
+
default:
return true;
}
}
+\f
+/* Save EXP for later use or reuse. This is equivalent to save_expr in tree.c
+ but we know how to handle our own nodes. */
+
+tree
+gnat_save_expr (tree exp)
+{
+ tree type = TREE_TYPE (exp);
+ enum tree_code code = TREE_CODE (exp);
+
+ if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
+ return exp;
+
+ if (code == UNCONSTRAINED_ARRAY_REF)
+ {
+ tree t = build1 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)));
+ TREE_READONLY (t) = TYPE_READONLY (type);
+ return t;
+ }
+
+ /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
+ This may be more efficient, but will also allow us to more easily find
+ the match for the PLACEHOLDER_EXPR. */
+ if (code == COMPONENT_REF
+ && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
+ return build3 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)),
+ TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
+
+ return save_expr (exp);
+}
+
+/* Protect EXP for immediate reuse. This is a variant of gnat_save_expr that
+ is optimized under the assumption that EXP's value doesn't change before
+ its subsequent reuse(s) except through its potential reevaluation. */
+
+tree
+gnat_protect_expr (tree exp)
+{
+ tree type = TREE_TYPE (exp);
+ enum tree_code code = TREE_CODE (exp);
+
+ if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
+ return exp;
+
+ /* If EXP has no side effects, we theoritically don't need to do anything.
+ However, we may be recursively passed more and more complex expressions
+ involving checks which will be reused multiple times and eventually be
+ unshared for gimplification; in order to avoid a complexity explosion
+ at that point, we protect any expressions more complex than a simple
+ arithmetic expression. */
+ if (!TREE_SIDE_EFFECTS (exp)
+ && !EXPRESSION_CLASS_P (skip_simple_arithmetic (exp)))
+ return exp;
+
+ /* If this is a conversion, protect what's inside the conversion. */
+ if (code == NON_LVALUE_EXPR
+ || CONVERT_EXPR_CODE_P (code)
+ || code == VIEW_CONVERT_EXPR)
+ return build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
+
+ /* If we're indirectly referencing something, we only need to protect the
+ address since the data itself can't change in these situations. */
+ if (code == INDIRECT_REF || code == UNCONSTRAINED_ARRAY_REF)
+ {
+ tree t = build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
+ TREE_READONLY (t) = TYPE_READONLY (type);
+ return t;
+ }
+
+ /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
+ This may be more efficient, but will also allow us to more easily find
+ the match for the PLACEHOLDER_EXPR. */
+ if (code == COMPONENT_REF
+ && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
+ return build3 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)),
+ TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
+
+ /* If this is a fat pointer or something that can be placed in a register,
+ just make a SAVE_EXPR. Likewise for a CALL_EXPR as large objects are
+ returned via invisible reference in most ABIs so the temporary will
+ directly be filled by the callee. */
+ if (TYPE_IS_FAT_POINTER_P (type)
+ || TYPE_MODE (type) != BLKmode
+ || code == CALL_EXPR)
+ return save_expr (exp);
+
+ /* Otherwise reference, protect the address and dereference. */
+ return
+ build_unary_op (INDIRECT_REF, type,
+ save_expr (build_unary_op (ADDR_EXPR,
+ build_reference_type (type),
+ exp)));
+}
+
+/* This is equivalent to stabilize_reference_1 in tree.c but we take an extra
+ argument to force evaluation of everything. */
+
+static tree
+gnat_stabilize_reference_1 (tree e, bool force)
+{
+ enum tree_code code = TREE_CODE (e);
+ tree type = TREE_TYPE (e);
+ tree result;
+
+ /* We cannot ignore const expressions because it might be a reference
+ to a const array but whose index contains side-effects. But we can
+ ignore things that are actual constant or that already have been
+ handled by this function. */
+ if (TREE_CONSTANT (e) || code == SAVE_EXPR)
+ return e;
+
+ switch (TREE_CODE_CLASS (code))
+ {
+ case tcc_exceptional:
+ case tcc_declaration:
+ case tcc_comparison:
+ case tcc_expression:
+ case tcc_reference:
+ case tcc_vl_exp:
+ /* If this is a COMPONENT_REF of a fat pointer, save the entire
+ fat pointer. This may be more efficient, but will also allow
+ us to more easily find the match for the PLACEHOLDER_EXPR. */
+ if (code == COMPONENT_REF
+ && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (e, 0))))
+ result
+ = build3 (code, type,
+ gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
+ TREE_OPERAND (e, 1), TREE_OPERAND (e, 2));
+ /* If the expression has side-effects, then encase it in a SAVE_EXPR
+ so that it will only be evaluated once. */
+ /* The tcc_reference and tcc_comparison classes could be handled as
+ below, but it is generally faster to only evaluate them once. */
+ else if (TREE_SIDE_EFFECTS (e) || force)
+ return save_expr (e);
+ else
+ return e;
+ break;
+
+ case tcc_binary:
+ /* Recursively stabilize each operand. */
+ result
+ = build2 (code, type,
+ gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
+ gnat_stabilize_reference_1 (TREE_OPERAND (e, 1), force));
+ break;
+
+ case tcc_unary:
+ /* Recursively stabilize each operand. */
+ result
+ = build1 (code, type,
+ gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force));
+ break;
+
+ default:
+ gcc_unreachable ();
+ }
+
+ /* See similar handling in gnat_stabilize_reference. */
+ TREE_READONLY (result) = TREE_READONLY (e);
+ TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (e);
+ TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
+
+ return result;
+}
+
+/* This is equivalent to stabilize_reference in tree.c but we know how to
+ handle our own nodes and we take extra arguments. FORCE says whether to
+ force evaluation of everything. We set SUCCESS to true unless we walk
+ through something we don't know how to stabilize. */
+
+tree
+gnat_stabilize_reference (tree ref, bool force, bool *success)
+{
+ tree type = TREE_TYPE (ref);
+ enum tree_code code = TREE_CODE (ref);
+ tree result;
+
+ /* Assume we'll success unless proven otherwise. */
+ if (success)
+ *success = true;
+
+ switch (code)
+ {
+ case CONST_DECL:
+ case VAR_DECL:
+ case PARM_DECL:
+ case RESULT_DECL:
+ /* No action is needed in this case. */
+ return ref;
+
+ case ADDR_EXPR:
+ CASE_CONVERT:
+ case FLOAT_EXPR:
+ case FIX_TRUNC_EXPR:
+ case VIEW_CONVERT_EXPR:
+ result
+ = build1 (code, type,
+ gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
+ success));
+ break;
+
+ case INDIRECT_REF:
+ case UNCONSTRAINED_ARRAY_REF:
+ result = build1 (code, type,
+ gnat_stabilize_reference_1 (TREE_OPERAND (ref, 0),
+ force));
+ break;
+
+ case COMPONENT_REF:
+ result = build3 (COMPONENT_REF, type,
+ gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
+ success),
+ TREE_OPERAND (ref, 1), NULL_TREE);
+ break;
+
+ case BIT_FIELD_REF:
+ result = build3 (BIT_FIELD_REF, type,
+ gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
+ success),
+ gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
+ force),
+ gnat_stabilize_reference_1 (TREE_OPERAND (ref, 2),
+ force));
+ break;
+
+ case ARRAY_REF:
+ case ARRAY_RANGE_REF:
+ result = build4 (code, type,
+ gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
+ success),
+ gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
+ force),
+ NULL_TREE, NULL_TREE);
+ break;
+
+ case CALL_EXPR:
+ result = gnat_stabilize_reference_1 (ref, force);
+ break;
+
+ case COMPOUND_EXPR:
+ result = build2 (COMPOUND_EXPR, type,
+ gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
+ success),
+ gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
+ force));
+ break;
+
+ case CONSTRUCTOR:
+ /* Constructors with 1 element are used extensively to formally
+ convert objects to special wrapping types. */
+ if (TREE_CODE (type) == RECORD_TYPE
+ && VEC_length (constructor_elt, CONSTRUCTOR_ELTS (ref)) == 1)
+ {
+ tree index
+ = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->index;
+ tree value
+ = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->value;
+ result
+ = build_constructor_single (type, index,
+ gnat_stabilize_reference_1 (value,
+ force));
+ }
+ else
+ {
+ if (success)
+ *success = false;
+ return ref;
+ }
+ break;
+
+ case ERROR_MARK:
+ ref = error_mark_node;
+
+ /* ... fall through to failure ... */
+
+ /* If arg isn't a kind of lvalue we recognize, make no change.
+ Caller should recognize the error for an invalid lvalue. */
+ default:
+ if (success)
+ *success = false;
+ return ref;
+ }
+
+ /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS set on the initial expression
+ may not be sustained across some paths, such as the way via build1 for
+ INDIRECT_REF. We reset those flags here in the general case, which is
+ consistent with the GCC version of this routine.
+
+ Special care should be taken regarding TREE_SIDE_EFFECTS, because some
+ paths introduce side-effects where there was none initially (e.g. if a
+ SAVE_EXPR is built) and we also want to keep track of that. */
+ TREE_READONLY (result) = TREE_READONLY (ref);
+ TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (ref);
+ TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
+
+ return result;
+}
git://gcc.gnu.org / gcc.git / blobdiff