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8sa1-gcc/gcc/ada/utils2.c
Eric Botcazou b55e7f34bc decl.c (gnat_to_gnu_entity): Do not set "const" flag on "pure" Ada subprograms if SJLJ exceptions are used. 
* decl.c (gnat_to_gnu_entity) <E_Procedure>: Do not set "const" flag
	on "pure" Ada subprograms if SJLJ exceptions are used.
	* trans.c (Handled_Sequence_Of_Statements_to_gnu): Set TREE_NO_WARNING
	on the declaration node of JMPBUF_SAVE.
	* utils.c (init_gigi_decls): Set DECL_IS_PURE on the declaration nodes
	of Get_Jmpbuf_Address_Soft and Get_GNAT_Exception.
	* utils2.c (build_call_0_expr): Do not set TREE_SIDE_EFFECTS.

From-SVN: r117299
2006-09-29 06:52:04 +00:00

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/****************************************************************************
* *
* GNAT COMPILER COMPONENTS *
* *
* U T I L S 2 *
* *
* C Implementation File *
* *
* Copyright (C) 1992-2006, 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- *
* ware Foundation; either version 2, or (at your option) any later ver- *
* sion. GNAT is distributed in the hope that it will be useful, but WITH- *
* OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
* for more details. You should have received a copy of the GNU General *
* Public License distributed with GNAT; see file COPYING. If not, write *
* to the Free Software Foundation, 51 Franklin Street, Fifth Floor, *
* Boston, MA 02110-1301, USA. *
* *
* GNAT was originally developed by the GNAT team at New York University. *
* Extensive contributions were provided by Ada Core Technologies Inc. *
* *
****************************************************************************/
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "rtl.h"
#include "ggc.h"
#include "flags.h"
#include "output.h"
#include "ada.h"
#include "types.h"
#include "atree.h"
#include "stringt.h"
#include "namet.h"
#include "uintp.h"
#include "fe.h"
#include "elists.h"
#include "nlists.h"
#include "sinfo.h"
#include "einfo.h"
#include "ada-tree.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);
/* 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) ? convert (type, integer_zero_node)
: convert (type, integer_one_node));
case REAL_CST:
return (real_zerop (expr) ? convert (type, integer_zero_node)
: convert (type, integer_one_node));
case COND_EXPR:
/* Distribute the conversion into the arms of a COND_EXPR. */
return fold
(build3 (COND_EXPR, type, TREE_OPERAND (expr, 0),
gnat_truthvalue_conversion (TREE_OPERAND (expr, 1)),
gnat_truthvalue_conversion (TREE_OPERAND (expr, 2))));
default:
return build_binary_op (NE_EXPR, type, expr,
convert (type, integer_zero_node));
}
}
/* Return the base type of TYPE. */
tree
get_base_type (tree type)
{
if (TREE_CODE (type) == RECORD_TYPE
&& TYPE_JUSTIFIED_MODULAR_P (type))
type = TREE_TYPE (TYPE_FIELDS (type));
while (TREE_TYPE (type)
&& (TREE_CODE (type) == INTEGER_TYPE
|| TREE_CODE (type) == REAL_TYPE))
type = TREE_TYPE (type);
return type;
}
/* EXP is a GCC tree representing an address. See if we can find how
strictly the object at that address is aligned. Return that alignment
in bits. If we don't know anything about the alignment, return 0. */
unsigned int
known_alignment (tree exp)
{
unsigned int this_alignment;
unsigned int lhs, rhs;
unsigned int type_alignment;
/* For pointer expressions, we know that the designated object is always at
least as strictly aligned as the designated subtype, so we account for
both type and expression information in this case.
Beware that we can still get a dummy designated subtype here (e.g. Taft
Amendement types), in which the alignment information is meaningless and
should be ignored.
We always compute a type_alignment value and return the MAX of it
compared with what we get from the expression tree. Just set the
type_alignment value to 0 when the type information is to be ignored. */
type_alignment
= ((POINTER_TYPE_P (TREE_TYPE (exp))
&& !TYPE_IS_DUMMY_P (TREE_TYPE (TREE_TYPE (exp))))
? TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp))) : 0);
switch (TREE_CODE (exp))
{
case CONVERT_EXPR:
case NOP_EXPR:
case NON_LVALUE_EXPR:
/* Conversions between pointers and integers don't change the alignment
of the underlying object. */
this_alignment = known_alignment (TREE_OPERAND (exp, 0));
break;
case PLUS_EXPR:
case MINUS_EXPR:
/* If two address are added, the alignment of the result is the
minimum of the two alignments. */
lhs = known_alignment (TREE_OPERAND (exp, 0));
rhs = known_alignment (TREE_OPERAND (exp, 1));
this_alignment = MIN (lhs, rhs);
break;
case INTEGER_CST:
/* The first part of this represents the lowest bit in the constant,
but is it in bytes, not bits. */
this_alignment
= MIN (BITS_PER_UNIT
* (TREE_INT_CST_LOW (exp) & - TREE_INT_CST_LOW (exp)),
BIGGEST_ALIGNMENT);
break;
case MULT_EXPR:
/* If we know the alignment of just one side, use it. Otherwise,
use the product of the alignments. */
lhs = known_alignment (TREE_OPERAND (exp, 0));
rhs = known_alignment (TREE_OPERAND (exp, 1));
if (lhs == 0 || rhs == 0)
this_alignment = MIN (BIGGEST_ALIGNMENT, MAX (lhs, rhs));
else
this_alignment = MIN (BIGGEST_ALIGNMENT, lhs * rhs);
break;
case ADDR_EXPR:
this_alignment = expr_align (TREE_OPERAND (exp, 0));
break;
default:
this_alignment = 0;
break;
}
return MAX (type_alignment, this_alignment);
}
/* We have a comparison or assignment operation on two types, T1 and T2,
which are both either array types or both record types.
Return the type that both operands should be converted to, if any.
Otherwise return zero. */
static tree
find_common_type (tree t1, tree t2)
{
/* If either type is non-BLKmode, use it. Note that we know that we will
not have any alignment problems since if we did the non-BLKmode
type could not have been used. */
if (TYPE_MODE (t1) != BLKmode)
return t1;
else if (TYPE_MODE (t2) != BLKmode)
return t2;
/* If both types have constant size, use the smaller one. Keep returning
T1 if we have a tie, to be consistent with the other cases. */
if (TREE_CONSTANT (TYPE_SIZE (t1)) && TREE_CONSTANT (TYPE_SIZE (t2)))
return tree_int_cst_lt (TYPE_SIZE (t2), TYPE_SIZE (t1)) ? t2 : t1;
/* Otherwise, if either type has a constant size, use it. */
else if (TREE_CONSTANT (TYPE_SIZE (t1)))
return t1;
else if (TREE_CONSTANT (TYPE_SIZE (t2)))
return t2;
/* In this case, both types have variable size. It's probably
best to leave the "type mismatch" because changing it could
case a bad self-referential reference. */
return 0;
}
/* 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. */
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 NOP_EXPR: case CONVERT_EXPR: 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;
}
}
/* 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;
}
}
/* 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. */
static tree
compare_arrays (tree result_type, tree a1, tree a2)
{
tree t1 = TREE_TYPE (a1);
tree t2 = TREE_TYPE (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 length_zero_p = false;
/* 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. */
while (TREE_CODE (t1) == ARRAY_TYPE && TREE_CODE (t2) == ARRAY_TYPE)
{
tree lb1 = TYPE_MIN_VALUE (TYPE_DOMAIN (t1));
tree ub1 = TYPE_MAX_VALUE (TYPE_DOMAIN (t1));
tree lb2 = TYPE_MIN_VALUE (TYPE_DOMAIN (t2));
tree ub2 = TYPE_MAX_VALUE (TYPE_DOMAIN (t2));
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;
/* If the length of the first array is a constant, swap our operands
unless the length of the second array is the constant zero.
Note that we have set the `length' values to the length - 1. */
if (TREE_CODE (length1) == INTEGER_CST
&& !integer_zerop (fold (build2 (PLUS_EXPR, bt, length2,
convert (bt, integer_one_node)))))
{
tem = a1, a1 = a2, a2 = tem;
tem = t1, t1 = t2, t2 = tem;
tem = lb1, lb1 = lb2, lb2 = tem;
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;
}
/* If the length of this dimension in the second array is the constant
zero, we can just go inside the original bounds for the first
array and see if last < first. */
if (integer_zerop (fold (build2 (PLUS_EXPR, bt, length2,
convert (bt, integer_one_node)))))
{
tree ub = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
tree lb = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
comparison = build_binary_op (LT_EXPR, result_type, ub, lb);
comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
length_zero_p = true;
this_a1_is_null = comparison;
this_a2_is_null = convert (result_type, integer_one_node);
}
/* If the length is some other constant value, we know that the
this dimension in the first array cannot be superflat, so we
can just use its length from the actual stored bounds. */
else if (TREE_CODE (length2) == INTEGER_CST)
{
ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
ub2 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
lb2 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
nbt = get_base_type (TREE_TYPE (ub1));
comparison
= build_binary_op (EQ_EXPR, result_type,
build_binary_op (MINUS_EXPR, nbt, ub1, lb1),
build_binary_op (MINUS_EXPR, nbt, ub2, lb2));
/* Note that we know that UB2 and LB2 are constant and hence
cannot contain a PLACEHOLDER_EXPR. */
comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
this_a1_is_null = build_binary_op (LT_EXPR, result_type, ub1, lb1);
this_a2_is_null = convert (result_type, integer_zero_node);
}
/* Otherwise compare the computed lengths. */
else
{
length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
length2 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length2, a2);
comparison
= build_binary_op (EQ_EXPR, result_type, length1, length2);
this_a1_is_null
= build_binary_op (LT_EXPR, result_type, length1,
convert (bt, integer_zero_node));
this_a2_is_null
= build_binary_op (LT_EXPR, result_type, length2,
convert (bt, integer_zero_node));
}
result = build_binary_op (TRUTH_ANDIF_EXPR, result_type,
result, comparison);
a1_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
this_a1_is_null, a1_is_null);
a2_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
this_a2_is_null, a2_is_null);
t1 = TREE_TYPE (t1);
t2 = TREE_TYPE (t2);
}
/* Unless the size of some bound is known to be zero, compare the
data in the array. */
if (!length_zero_p)
{
tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
if (type)
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. */
result = build_binary_op (TRUTH_ORIF_EXPR, result_type,
build_binary_op (TRUTH_ANDIF_EXPR, result_type,
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))
result = build2 (COMPOUND_EXPR, result_type, a1, result);
if (contains_save_expr_p (a2))
result = build2 (COMPOUND_EXPR, result_type, a2, result);
return result;
}
/* Compute the result of applying OP_CODE to LHS and RHS, where both are of
type TYPE. We know that TYPE is a modular type with a nonbinary
modulus. */
static tree
nonbinary_modular_operation (enum tree_code op_code, tree type, tree lhs,
tree rhs)
{
tree modulus = TYPE_MODULUS (type);
unsigned int needed_precision = tree_floor_log2 (modulus) + 1;
unsigned int precision;
bool unsignedp = true;
tree op_type = type;
tree result;
/* If this is an addition of a constant, convert it to a subtraction
of a constant since we can do that faster. */
if (op_code == PLUS_EXPR && TREE_CODE (rhs) == INTEGER_CST)
rhs = fold (build2 (MINUS_EXPR, type, modulus, rhs)), op_code = MINUS_EXPR;
/* For the logical operations, we only need PRECISION bits. For
addition and subtraction, we need one more and for multiplication we
need twice as many. But we never want to make a size smaller than
our size. */
if (op_code == PLUS_EXPR || op_code == MINUS_EXPR)
needed_precision += 1;
else if (op_code == MULT_EXPR)
needed_precision *= 2;
precision = MAX (needed_precision, TYPE_PRECISION (op_type));
/* Unsigned will do for everything but subtraction. */
if (op_code == MINUS_EXPR)
unsignedp = false;
/* If our type is the wrong signedness or isn't wide enough, make a new
type and convert both our operands to it. */
if (TYPE_PRECISION (op_type) < precision
|| TYPE_UNSIGNED (op_type) != unsignedp)
{
/* Copy the node so we ensure it can be modified to make it modular. */
op_type = copy_node (gnat_type_for_size (precision, unsignedp));
modulus = convert (op_type, modulus);
SET_TYPE_MODULUS (op_type, modulus);
TYPE_MODULAR_P (op_type) = 1;
lhs = convert (op_type, lhs);
rhs = convert (op_type, rhs);
}
/* Do the operation, then we'll fix it up. */
result = fold (build2 (op_code, op_type, lhs, rhs));
/* For multiplication, we have no choice but to do a full modulus
operation. However, we want to do this in the narrowest
possible size. */
if (op_code == MULT_EXPR)
{
tree div_type = copy_node (gnat_type_for_size (needed_precision, 1));
modulus = convert (div_type, modulus);
SET_TYPE_MODULUS (div_type, modulus);
TYPE_MODULAR_P (div_type) = 1;
result = convert (op_type,
fold (build2 (TRUNC_MOD_EXPR, div_type,
convert (div_type, result), modulus)));
}
/* For subtraction, add the modulus back if we are negative. */
else if (op_code == MINUS_EXPR)
{
result = save_expr (result);
result = fold (build3 (COND_EXPR, op_type,
build2 (LT_EXPR, integer_type_node, result,
convert (op_type, integer_zero_node)),
fold (build2 (PLUS_EXPR, op_type,
result, modulus)),
result));
}
/* For the other operations, subtract the modulus if we are >= it. */
else
{
result = save_expr (result);
result = fold (build3 (COND_EXPR, op_type,
build2 (GE_EXPR, integer_type_node,
result, modulus),
fold (build2 (MINUS_EXPR, op_type,
result, modulus)),
result));
}
return convert (type, result);
}
/* Make a binary operation of kind OP_CODE. RESULT_TYPE is the type
desired for the result. Usually the operation is to be performed
in that type. For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
in which case the type to be used will be derived from the operands.
This function is very much unlike the ones for C and C++ since we
have already done any type conversion and matching required. All we
have to do here is validate the work done by SEM and handle subtypes. */
tree
build_binary_op (enum tree_code op_code, tree result_type,
tree left_operand, tree right_operand)
{
tree left_type = TREE_TYPE (left_operand);
tree right_type = TREE_TYPE (right_operand);
tree left_base_type = get_base_type (left_type);
tree right_base_type = get_base_type (right_type);
tree operation_type = result_type;
tree best_type = NULL_TREE;
tree modulus;
tree result;
bool has_side_effects = false;
if (operation_type
&& TREE_CODE (operation_type) == RECORD_TYPE
&& TYPE_JUSTIFIED_MODULAR_P (operation_type))
operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
if (operation_type
&& !AGGREGATE_TYPE_P (operation_type)
&& TYPE_EXTRA_SUBTYPE_P (operation_type))
operation_type = get_base_type (operation_type);
modulus = (operation_type && TREE_CODE (operation_type) == INTEGER_TYPE
&& TYPE_MODULAR_P (operation_type)
? TYPE_MODULUS (operation_type) : 0);
switch (op_code)
{
case MODIFY_EXPR:
/* If there were any integral or pointer conversions on LHS, remove
them; we'll be putting them back below if needed. Likewise for
conversions between array and record types. But don't do this if
the right operand is not BLKmode (for packed arrays)
unless we are not changing the mode. */
while ((TREE_CODE (left_operand) == CONVERT_EXPR
|| TREE_CODE (left_operand) == NOP_EXPR
|| TREE_CODE (left_operand) == VIEW_CONVERT_EXPR)
&& (((INTEGRAL_TYPE_P (left_type)
|| POINTER_TYPE_P (left_type))
&& (INTEGRAL_TYPE_P (TREE_TYPE
(TREE_OPERAND (left_operand, 0)))
|| POINTER_TYPE_P (TREE_TYPE
(TREE_OPERAND (left_operand, 0)))))
|| (((TREE_CODE (left_type) == RECORD_TYPE
/* Don't remove conversions to justified modular
types. */
&& !TYPE_JUSTIFIED_MODULAR_P (left_type))
|| TREE_CODE (left_type) == ARRAY_TYPE)
&& ((TREE_CODE (TREE_TYPE
(TREE_OPERAND (left_operand, 0)))
== RECORD_TYPE)
|| (TREE_CODE (TREE_TYPE
(TREE_OPERAND (left_operand, 0)))
== ARRAY_TYPE))
&& (TYPE_MODE (right_type) == BLKmode
|| (TYPE_MODE (left_type)
== TYPE_MODE (TREE_TYPE
(TREE_OPERAND
(left_operand, 0))))))))
{
left_operand = TREE_OPERAND (left_operand, 0);
left_type = TREE_TYPE (left_operand);
}
if (!operation_type)
operation_type = left_type;
/* If we are copying one array or record to another, find the best type
to use. */
if (((TREE_CODE (left_type) == ARRAY_TYPE
&& TREE_CODE (right_type) == ARRAY_TYPE)
|| (TREE_CODE (left_type) == RECORD_TYPE
&& TREE_CODE (right_type) == RECORD_TYPE))
&& (best_type = find_common_type (left_type, right_type)))
operation_type = best_type;
/* If a class-wide type may be involved, force use of the RHS type. */
if ((TREE_CODE (right_type) == RECORD_TYPE
|| TREE_CODE (right_type) == UNION_TYPE)
&& TYPE_ALIGN_OK (right_type))
operation_type = right_type;
/* Ensure everything on the LHS is valid. If we have a field reference,
strip anything that get_inner_reference can handle. Then remove any
conversions with type types having the same code and mode. Mark
VIEW_CONVERT_EXPRs with TREE_ADDRESSABLE. When done, we must have
either an INDIRECT_REF or a decl. */
result = left_operand;
while (1)
{
tree restype = TREE_TYPE (result);
if (TREE_CODE (result) == COMPONENT_REF
|| TREE_CODE (result) == ARRAY_REF
|| TREE_CODE (result) == ARRAY_RANGE_REF)
while (handled_component_p (result))
result = TREE_OPERAND (result, 0);
else if (TREE_CODE (result) == REALPART_EXPR
|| TREE_CODE (result) == IMAGPART_EXPR
|| ((TREE_CODE (result) == NOP_EXPR
|| TREE_CODE (result) == CONVERT_EXPR)
&& (((TREE_CODE (restype)
== TREE_CODE (TREE_TYPE
(TREE_OPERAND (result, 0))))
&& (TYPE_MODE (TREE_TYPE
(TREE_OPERAND (result, 0)))
== TYPE_MODE (restype)))
|| TYPE_ALIGN_OK (restype))))
result = TREE_OPERAND (result, 0);
else if (TREE_CODE (result) == VIEW_CONVERT_EXPR)
{
TREE_ADDRESSABLE (result) = 1;
result = TREE_OPERAND (result, 0);
}
else
break;
}
gcc_assert (TREE_CODE (result) == INDIRECT_REF
|| TREE_CODE (result) == NULL_EXPR || DECL_P (result));
/* Convert the right operand to the operation type unless
it is either already of the correct type or if the type
involves a placeholder, since the RHS may not have the same
record type. */
if (operation_type != right_type
&& (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (operation_type))))
{
right_operand = convert (operation_type, right_operand);
right_type = operation_type;
}
/* If the left operand is not the same type as the operation type,
surround it in a VIEW_CONVERT_EXPR. */
if (left_type != operation_type)
left_operand = unchecked_convert (operation_type, left_operand, false);
has_side_effects = true;
modulus = NULL_TREE;
break;
case ARRAY_REF:
if (!operation_type)
operation_type = TREE_TYPE (left_type);
/* ... fall through ... */
case ARRAY_RANGE_REF:
/* First convert the right operand to its base type. This will
prevent unneeded signedness conversions when sizetype is wider than
integer. */
right_operand = convert (right_base_type, right_operand);
right_operand = convert (TYPE_DOMAIN (left_type), right_operand);
if (!TREE_CONSTANT (right_operand)
|| !TREE_CONSTANT (TYPE_MIN_VALUE (right_type)))
gnat_mark_addressable (left_operand);
modulus = NULL_TREE;
break;
case GE_EXPR:
case LE_EXPR:
case GT_EXPR:
case LT_EXPR:
gcc_assert (!POINTER_TYPE_P (left_type));
/* ... fall through ... */
case EQ_EXPR:
case NE_EXPR:
/* If either operand is a NULL_EXPR, just return a new one. */
if (TREE_CODE (left_operand) == NULL_EXPR)
return build2 (op_code, result_type,
build1 (NULL_EXPR, integer_type_node,
TREE_OPERAND (left_operand, 0)),
integer_zero_node);
else if (TREE_CODE (right_operand) == NULL_EXPR)
return build2 (op_code, result_type,
build1 (NULL_EXPR, integer_type_node,
TREE_OPERAND (right_operand, 0)),
integer_zero_node);
/* If either object is a justified modular types, get the
fields from within. */
if (TREE_CODE (left_type) == RECORD_TYPE
&& TYPE_JUSTIFIED_MODULAR_P (left_type))
{
left_operand = convert (TREE_TYPE (TYPE_FIELDS (left_type)),
left_operand);
left_type = TREE_TYPE (left_operand);
left_base_type = get_base_type (left_type);
}
if (TREE_CODE (right_type) == RECORD_TYPE
&& TYPE_JUSTIFIED_MODULAR_P (right_type))
{
right_operand = convert (TREE_TYPE (TYPE_FIELDS (right_type)),
right_operand);
right_type = TREE_TYPE (right_operand);
right_base_type = get_base_type (right_type);
}
/* If both objects are arrays, compare them specially. */
if ((TREE_CODE (left_type) == ARRAY_TYPE
|| (TREE_CODE (left_type) == INTEGER_TYPE
&& TYPE_HAS_ACTUAL_BOUNDS_P (left_type)))
&& (TREE_CODE (right_type) == ARRAY_TYPE
|| (TREE_CODE (right_type) == INTEGER_TYPE
&& TYPE_HAS_ACTUAL_BOUNDS_P (right_type))))
{
result = compare_arrays (result_type, left_operand, right_operand);
if (op_code == NE_EXPR)
result = invert_truthvalue (result);
else
gcc_assert (op_code == EQ_EXPR);
return result;
}
/* Otherwise, the base types must be the same unless the objects are
records. If we have records, use the best type and convert both
operands to that type. */
if (left_base_type != right_base_type)
{
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. */
best_type = NULL_TREE;
gcc_assert (TYPE_NAME (left_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 if (TREE_CONSTANT (TYPE_SIZE (right_base_type)))
best_type = right_base_type;
else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type)))
best_type = left_base_type;
else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type)))
best_type = right_base_type;
else
gcc_unreachable ();
left_operand = convert (best_type, left_operand);
right_operand = convert (best_type, right_operand);
}
else
gcc_unreachable ();
}
/* 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);
}
modulus = NULL_TREE;
break;
case PREINCREMENT_EXPR:
case PREDECREMENT_EXPR:
case POSTINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
/* In these, the result type and the left operand type should be the
same. Do the operation in the base type of those and convert the
right operand (which is an integer) to that type.
Note that these operations are only used in loop control where
we guarantee that no overflow can occur. So nothing special need
be done for modular types. */
gcc_assert (left_type == result_type);
operation_type = get_base_type (result_type);
left_operand = convert (operation_type, left_operand);
right_operand = convert (operation_type, right_operand);
has_side_effects = true;
modulus = NULL_TREE;
break;
case LSHIFT_EXPR:
case RSHIFT_EXPR:
case LROTATE_EXPR:
case RROTATE_EXPR:
/* The RHS of a shift can be any type. Also, ignore any modulus
(we used to abort, but this is needed for unchecked conversion
to modular types). Otherwise, processing is the same as normal. */
gcc_assert (operation_type == left_base_type);
modulus = NULL_TREE;
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:
/* For binary modulus, if the inputs are in range, so are the
outputs. */
if (modulus && integer_pow2p (modulus))
modulus = NULL_TREE;
goto common;
case COMPLEX_EXPR:
gcc_assert (TREE_TYPE (result_type) == left_base_type
&& TREE_TYPE (result_type) == right_base_type);
left_operand = convert (left_base_type, left_operand);
right_operand = convert (right_base_type, right_operand);
break;
case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR:
case CEIL_DIV_EXPR: case CEIL_MOD_EXPR:
case FLOOR_DIV_EXPR: case FLOOR_MOD_EXPR:
case ROUND_DIV_EXPR: case ROUND_MOD_EXPR:
/* These always produce results lower than either operand. */
modulus = NULL_TREE;
goto common;
default:
common:
/* The result type should be the same as the base types of the
both operands (and they should be the same). Convert
everything to the result type. */
gcc_assert (operation_type == left_base_type
&& left_base_type == right_base_type);
left_operand = convert (operation_type, left_operand);
right_operand = convert (operation_type, right_operand);
}
if (modulus && !integer_pow2p (modulus))
{
result = nonbinary_modular_operation (op_code, operation_type,
left_operand, right_operand);
modulus = NULL_TREE;
}
/* If either operand is a NULL_EXPR, just return a new one. */
else if (TREE_CODE (left_operand) == NULL_EXPR)
return build1 (NULL_EXPR, operation_type, TREE_OPERAND (left_operand, 0));
else if (TREE_CODE (right_operand) == NULL_EXPR)
return build1 (NULL_EXPR, operation_type, TREE_OPERAND (right_operand, 0));
else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
result = fold (build4 (op_code, operation_type, left_operand,
right_operand, NULL_TREE, NULL_TREE));
else
result
= fold (build2 (op_code, operation_type, left_operand, right_operand));
TREE_SIDE_EFFECTS (result) |= has_side_effects;
TREE_CONSTANT (result)
|= (TREE_CONSTANT (left_operand) & TREE_CONSTANT (right_operand)
&& op_code != ARRAY_REF && op_code != ARRAY_RANGE_REF);
if ((op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
&& TYPE_VOLATILE (operation_type))
TREE_THIS_VOLATILE (result) = 1;
/* If we are working with modular types, perform the MOD operation
if something above hasn't eliminated the need for it. */
if (modulus)
result = fold (build2 (FLOOR_MOD_EXPR, operation_type, result,
convert (operation_type, modulus)));
if (result_type && result_type != operation_type)
result = convert (result_type, result);
return result;
}
/* Similar, but for unary operations. */
tree
build_unary_op (enum tree_code op_code, tree result_type, tree operand)
{
tree type = TREE_TYPE (operand);
tree base_type = get_base_type (type);
tree operation_type = result_type;
tree result;
bool side_effects = false;
if (operation_type
&& TREE_CODE (operation_type) == RECORD_TYPE
&& TYPE_JUSTIFIED_MODULAR_P (operation_type))
operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
if (operation_type
&& !AGGREGATE_TYPE_P (operation_type)
&& TYPE_EXTRA_SUBTYPE_P (operation_type))
operation_type = get_base_type (operation_type);
switch (op_code)
{
case REALPART_EXPR:
case IMAGPART_EXPR:
if (!operation_type)
result_type = operation_type = TREE_TYPE (type);
else
gcc_assert (result_type == TREE_TYPE (type));
result = fold (build1 (op_code, operation_type, operand));
break;
case TRUTH_NOT_EXPR:
gcc_assert (result_type == base_type);
result = invert_truthvalue (gnat_truthvalue_conversion (operand));
break;
case ATTR_ADDR_EXPR:
case ADDR_EXPR:
switch (TREE_CODE (operand))
{
case INDIRECT_REF:
case UNCONSTRAINED_ARRAY_REF:
result = TREE_OPERAND (operand, 0);
/* Make sure the type here is a pointer, not a reference.
GCC wants pointer types for function addresses. */
if (!result_type)
result_type = build_pointer_type (type);
break;
case NULL_EXPR:
result = operand;
TREE_TYPE (result) = type = build_pointer_type (type);
break;
case ARRAY_REF:
case ARRAY_RANGE_REF:
case COMPONENT_REF:
case BIT_FIELD_REF:
/* If this is for 'Address, find the address of the prefix and
add the offset to the field. Otherwise, do this the normal
way. */
if (op_code == ATTR_ADDR_EXPR)
{
HOST_WIDE_INT bitsize;
HOST_WIDE_INT bitpos;
tree offset, inner;
enum machine_mode mode;
int unsignedp, volatilep;
inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
&mode, &unsignedp, &volatilep,
false);
/* 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)))))))
inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
inner);
/* Compute the offset as a byte offset from INNER. */
if (!offset)
offset = size_zero_node;
if (bitpos % BITS_PER_UNIT != 0)
post_error
("taking address of object not aligned on storage unit?",
error_gnat_node);
offset = size_binop (PLUS_EXPR, offset,
size_int (bitpos / BITS_PER_UNIT));
/* Take the address of INNER, convert the offset to void *, and
add then. It will later be converted to the desired result
type, if any. */
inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
inner = convert (ptr_void_type_node, inner);
offset = convert (ptr_void_type_node, offset);
result = build_binary_op (PLUS_EXPR, ptr_void_type_node,
inner, offset);
result = convert (build_pointer_type (TREE_TYPE (operand)),
result);
break;
}
goto common;
case CONSTRUCTOR:
/* 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))
{
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;
}
goto common;
case NOP_EXPR:
if (AGGREGATE_TYPE_P (type)
&& AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
return build_unary_op (ADDR_EXPR, result_type,
TREE_OPERAND (operand, 0));
/* ... fallthru ... */
case VIEW_CONVERT_EXPR:
/* If this just a variant conversion or if the conversion doesn't
change the mode, get the result type from this type and go down.
This is needed for conversions of CONST_DECLs, to eventually get
to the address of their CORRESPONDING_VARs. */
if ((TYPE_MAIN_VARIANT (type)
== TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
|| (TYPE_MODE (type) != BLKmode
&& (TYPE_MODE (type)
== TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
return build_unary_op (ADDR_EXPR,
(result_type ? result_type
: build_pointer_type (type)),
TREE_OPERAND (operand, 0));
goto common;
case CONST_DECL:
operand = DECL_CONST_CORRESPONDING_VAR (operand);
/* ... fall through ... */
default:
common:
/* 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)
&& TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
&& TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
{
type = TREE_TYPE (TYPE_FIELDS (type));
operand = convert (type, operand);
}
if (type != error_mark_node)
operation_type = build_pointer_type (type);
gnat_mark_addressable (operand);
result = fold (build1 (ADDR_EXPR, operation_type, operand));
}
TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
break;
case INDIRECT_REF:
/* If we want to refer to an entire unconstrained array,
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)
&& TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
{
operand
= convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
operand);
type = TREE_TYPE (operand);
}
if (TYPE_FAT_POINTER_P (type))
{
result = build1 (UNCONSTRAINED_ARRAY_REF,
TYPE_UNCONSTRAINED_ARRAY (type), operand);
TREE_READONLY (result) = TREE_STATIC (result)
= TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
}
else if (TREE_CODE (operand) == ADDR_EXPR)
result = TREE_OPERAND (operand, 0);
else
{
result = fold (build1 (op_code, TREE_TYPE (type), operand));
TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
}
side_effects
= (!TYPE_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
break;
case NEGATE_EXPR:
case BIT_NOT_EXPR:
{
tree modulus = ((operation_type
&& TREE_CODE (operation_type) == INTEGER_TYPE
&& TYPE_MODULAR_P (operation_type))
? TYPE_MODULUS (operation_type) : 0);
int mod_pow2 = modulus && integer_pow2p (modulus);
/* If this is a modular type, there are various possibilities
depending on the operation and whether the modulus is a
power of two or not. */
if (modulus)
{
gcc_assert (operation_type == base_type);
operand = convert (operation_type, operand);
/* The fastest in the negate case for binary modulus is
the straightforward code; the TRUNC_MOD_EXPR below
is an AND operation. */
if (op_code == NEGATE_EXPR && mod_pow2)
result = fold (build2 (TRUNC_MOD_EXPR, operation_type,
fold (build1 (NEGATE_EXPR, operation_type,
operand)),
modulus));
/* For nonbinary negate case, return zero for zero operand,
else return the modulus minus the operand. If the modulus
is a power of two minus one, we can do the subtraction
as an XOR since it is equivalent and faster on most machines. */
else if (op_code == NEGATE_EXPR && !mod_pow2)
{
if (integer_pow2p (fold (build2 (PLUS_EXPR, operation_type,
modulus,
convert (operation_type,
integer_one_node)))))
result = fold (build2 (BIT_XOR_EXPR, operation_type,
operand, modulus));
else
result = fold (build2 (MINUS_EXPR, operation_type,
modulus, operand));
result = fold (build3 (COND_EXPR, operation_type,
fold (build2 (NE_EXPR,
integer_type_node,
operand,
convert
(operation_type,
integer_zero_node))),
result, operand));
}
else
{
/* For the NOT cases, we need a constant equal to
the modulus minus one. For a binary modulus, we
XOR against the constant and subtract the operand from
that constant for nonbinary modulus. */
tree cnst = fold (build2 (MINUS_EXPR, operation_type, modulus,
convert (operation_type,
integer_one_node)));
if (mod_pow2)
result = fold (build2 (BIT_XOR_EXPR, operation_type,
operand, cnst));
else
result = fold (build2 (MINUS_EXPR, operation_type,
cnst, operand));
}
break;
}
}
/* ... fall through ... */
default:
gcc_assert (operation_type == base_type);
result = fold (build1 (op_code, operation_type, convert (operation_type,
operand)));
}
if (side_effects)
{
TREE_SIDE_EFFECTS (result) = 1;
if (TREE_CODE (result) == INDIRECT_REF)
TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
}
if (result_type && TREE_TYPE (result) != result_type)
result = convert (result_type, result);
return result;
}
/* Similar, but for COND_EXPR. */
tree
build_cond_expr (tree result_type, tree condition_operand,
tree true_operand, tree false_operand)
{
tree result;
bool addr_p = false;
/* The front-end verifies that result, true and false operands have same base
type. Convert everything to the result type. */
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 (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
|| CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
{
addr_p = true;
result_type = build_pointer_type (result_type);
true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
false_operand = build_unary_op (ADDR_EXPR, result_type, false_operand);
}
result = fold (build3 (COND_EXPR, result_type, condition_operand,
true_operand, false_operand));
/* If either operand is a SAVE_EXPR (possibly surrounded by
arithmetic, make sure it gets done. */
true_operand = skip_simple_arithmetic (true_operand);
false_operand = skip_simple_arithmetic (false_operand);
if (TREE_CODE (true_operand) == SAVE_EXPR)
result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
if (TREE_CODE (false_operand) == SAVE_EXPR)
result = build2 (COMPOUND_EXPR, result_type, false_operand, result);
/* ??? Seems the code above is wrong, as it may move ahead of the COND
SAVE_EXPRs with side effects and not shared by both arms. */
if (addr_p)
result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
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. */
tree
build_return_expr (tree result_decl, tree ret_val)
{
tree result_expr;
if (result_decl)
{
/* The gimplifier explicitly enforces the following invariant:
RETURN_EXPR
|
MODIFY_EXPR
/ \
/ \
RESULT_DECL ...
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. */
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);
}
else
result_expr = NULL_TREE;
return build1 (RETURN_EXPR, void_type_node, result_expr);
}
/* Build a CALL_EXPR to call FUNDECL with one argument, ARG. Return
the CALL_EXPR. */
tree
build_call_1_expr (tree fundecl, tree arg)
{
tree call = build3 (CALL_EXPR, TREE_TYPE (TREE_TYPE (fundecl)),
build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
chainon (NULL_TREE, build_tree_list (NULL_TREE, arg)),
NULL_TREE);
TREE_SIDE_EFFECTS (call) = 1;
return call;
}
/* Build a CALL_EXPR to call FUNDECL with two arguments, ARG1 & ARG2. Return
the CALL_EXPR. */
tree
build_call_2_expr (tree fundecl, tree arg1, tree arg2)
{
tree call = build3 (CALL_EXPR, TREE_TYPE (TREE_TYPE (fundecl)),
build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
chainon (chainon (NULL_TREE,
build_tree_list (NULL_TREE, arg1)),
build_tree_list (NULL_TREE, arg2)),
NULL_TREE);
TREE_SIDE_EFFECTS (call) = 1;
return call;
}
/* Likewise to call FUNDECL with no arguments. */
tree
build_call_0_expr (tree fundecl)
{
tree call = build3 (CALL_EXPR, TREE_TYPE (TREE_TYPE (fundecl)),
build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
NULL_TREE, NULL_TREE);
/* We rely on build3 to compute TREE_SIDE_EFFECTS. This makes it possible
to propagate the DECL_IS_PURE flag on parameterless functions. */
return call;
}
/* Call a function that raises an exception and pass the line number and file
name, if requested. MSG says which exception function to call.
GNAT_NODE is the gnat node conveying the source location for which the
error should be signaled, or Empty in which case the error is signaled on
the current ref_file_name/input_line. */
tree
build_call_raise (int msg, Node_Id gnat_node)
{
tree fndecl = gnat_raise_decls[msg];
const char *str
= (Debug_Flag_NN || Exception_Locations_Suppressed)
? ""
: (gnat_node != Empty)
? IDENTIFIER_POINTER
(get_identifier (Get_Name_String
(Debug_Source_Name
(Get_Source_File_Index (Sloc (gnat_node))))))
: ref_filename;
int len = strlen (str) + 1;
tree filename = build_string (len, str);
int line_number
= (gnat_node != Empty)
? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
TREE_TYPE (filename)
= build_array_type (char_type_node,
build_index_type (build_int_cst (NULL_TREE, len)));
return
build_call_2_expr (fndecl,
build1 (ADDR_EXPR, build_pointer_type (char_type_node),
filename),
build_int_cst (NULL_TREE, line_number));
}
/* qsort comparer for the bit positions of two constructor elements
for record components. */
static int
compare_elmt_bitpos (const PTR rt1, const PTR rt2)
{
tree elmt1 = * (tree *) rt1;
tree elmt2 = * (tree *) rt2;
tree pos_field1 = bit_position (TREE_PURPOSE (elmt1));
tree pos_field2 = bit_position (TREE_PURPOSE (elmt2));
if (tree_int_cst_equal (pos_field1, pos_field2))
return 0;
else if (tree_int_cst_lt (pos_field1, pos_field2))
return -1;
else
return 1;
}
/* Return a CONSTRUCTOR of TYPE whose list is LIST. */
tree
gnat_build_constructor (tree type, tree list)
{
tree elmt;
int n_elmts;
bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
bool side_effects = false;
tree result;
/* Scan the elements to see if they are all constant or if any has side
effects, to let us set global flags on the resulting constructor. Count
the elements along the way for possible sorting purposes below. */
for (n_elmts = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), n_elmts ++)
{
if (!TREE_CONSTANT (TREE_VALUE (elmt))
|| (TREE_CODE (type) == RECORD_TYPE
&& DECL_BIT_FIELD (TREE_PURPOSE (elmt))
&& TREE_CODE (TREE_VALUE (elmt)) != INTEGER_CST)
|| !initializer_constant_valid_p (TREE_VALUE (elmt),
TREE_TYPE (TREE_VALUE (elmt))))
allconstant = false;
if (TREE_SIDE_EFFECTS (TREE_VALUE (elmt)))
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 cmpiler blowing up. */
if (TREE_CODE (type) == RECORD_TYPE
&& (0 != (result
= contains_null_expr (DECL_SIZE (TREE_PURPOSE (elmt))))))
return build1 (NULL_EXPR, type, TREE_OPERAND (result, 0));
}
/* For record types with constant components only, sort field list
by increasing bit position. This is necessary to ensure the
constructor can be output as static data, which the gimplifier
might force in various circumstances. */
if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
{
/* Fill an array with an element tree per index, and ask qsort to order
them according to what a bitpos comparison function says. */
tree *gnu_arr = (tree *) alloca (sizeof (tree) * n_elmts);
int i;
for (i = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), i++)
gnu_arr[i] = elmt;
qsort (gnu_arr, n_elmts, sizeof (tree), compare_elmt_bitpos);
/* Then reconstruct the list from the sorted array contents. */
list = NULL_TREE;
for (i = n_elmts - 1; i >= 0; i--)
{
TREE_CHAIN (gnu_arr[i]) = list;
list = gnu_arr[i];
}
}
result = build_constructor_from_list (type, list);
TREE_CONSTANT (result) = TREE_INVARIANT (result)
= TREE_STATIC (result) = allconstant;
TREE_SIDE_EFFECTS (result) = side_effects;
TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
return result;
}
/* Return a COMPONENT_REF to access a field that is given by COMPONENT,
an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
for the field. Don't fold the result if NO_FOLD_P is true.
We also handle the fact that we might have been passed a pointer to the
actual record and know how to look for fields in variant parts. */
static tree
build_simple_component_ref (tree record_variable, tree component,
tree field, bool no_fold_p)
{
tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
tree ref;
gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
|| TREE_CODE (record_type) == UNION_TYPE
|| TREE_CODE (record_type) == QUAL_UNION_TYPE)
&& TYPE_SIZE (record_type)
&& (component != 0) != (field != 0));
/* If no field was specified, look for a field with the specified name
in the current record only. */
if (!field)
for (field = TYPE_FIELDS (record_type); field;
field = TREE_CHAIN (field))
if (DECL_NAME (field) == component)
break;
if (!field)
return NULL_TREE;
/* If this field is not in the specified record, see if we can find
something in the record whose original field is the same as this one. */
if (DECL_CONTEXT (field) != record_type)
/* Check if there is a field with name COMPONENT in the record. */
{
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))))
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))
if (DECL_INTERNAL_P (new_field))
{
tree field_ref
= build_simple_component_ref (record_variable,
NULL_TREE, new_field, no_fold_p);
ref = build_simple_component_ref (field_ref, NULL_TREE, field,
no_fold_p);
if (ref)
return ref;
}
field = new_field;
}
if (!field)
return NULL_TREE;
/* If the field's offset has overflowed, do not attempt to access it
as doing so may trigger sanity checks deeper in the back-end.
Note that we don't need to warn since this will be done on trying
to declare the object. */
if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
&& TREE_CONSTANT_OVERFLOW (DECL_FIELD_OFFSET (field)))
return NULL_TREE;
/* It would be nice to call "fold" here, but that can lose a type
we need to tag a PLACEHOLDER_EXPR with, so we can't do it. */
ref = build3 (COMPONENT_REF, TREE_TYPE (field), record_variable, field,
NULL_TREE);
if (TREE_READONLY (record_variable) || TREE_READONLY (field))
TREE_READONLY (ref) = 1;
if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
|| TYPE_VOLATILE (record_type))
TREE_THIS_VOLATILE (ref) = 1;
return no_fold_p ? ref : fold (ref);
}
/* Like build_simple_component_ref, except that we give an error if the
reference could not be found. */
tree
build_component_ref (tree record_variable, tree component,
tree field, bool no_fold_p)
{
tree ref = build_simple_component_ref (record_variable, component, field,
no_fold_p);
if (ref)
return ref;
/* If FIELD was specified, assume this is an invalid user field so
raise constraint error. Otherwise, we can't find the type to return, so
abort. */
gcc_assert (field);
return build1 (NULL_EXPR, TREE_TYPE (field),
build_call_raise (CE_Discriminant_Check_Failed, Empty));
}
/* Build a GCC tree to call an allocation or deallocation function.
If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
generate an allocator.
GNU_SIZE is the size of the object in bytes and ALIGN is the alignment in
bits. GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the
storage pool to use. If not preset, malloc and free will be used except
if GNAT_PROC is the "fake" value of -1, in which case we allocate the
object dynamically on the stack frame. */
tree
build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, unsigned align,
Entity_Id gnat_proc, Entity_Id gnat_pool,
Node_Id gnat_node)
{
tree gnu_align = size_int (align / BITS_PER_UNIT);
gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
if (Present (gnat_proc))
{
/* The storage pools are obviously always tagged types, but the
secondary stack uses the same mechanism and is not tagged */
if (Is_Tagged_Type (Etype (gnat_pool)))
{
/* The size is the third parameter; the alignment is the
same type. */
Entity_Id gnat_size_type
= Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
tree gnu_proc = gnat_to_gnu (gnat_proc);
tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
tree gnu_pool = gnat_to_gnu (gnat_pool);
tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
tree gnu_args = NULL_TREE;
tree gnu_call;
/* The first arg is always the address of the storage pool; next
comes the address of the object, for a deallocator, then the
size and alignment. */
gnu_args
= chainon (gnu_args, build_tree_list (NULL_TREE, gnu_pool_addr));
if (gnu_obj)
gnu_args
= chainon (gnu_args, build_tree_list (NULL_TREE, gnu_obj));
gnu_args
= chainon (gnu_args,
build_tree_list (NULL_TREE,
convert (gnu_size_type, gnu_size)));
gnu_args
= chainon (gnu_args,
build_tree_list (NULL_TREE,
convert (gnu_size_type, gnu_align)));
gnu_call = build3 (CALL_EXPR, TREE_TYPE (TREE_TYPE (gnu_proc)),
gnu_proc_addr, gnu_args, NULL_TREE);
TREE_SIDE_EFFECTS (gnu_call) = 1;
return gnu_call;
}
/* Secondary stack case. */
else
{
/* The size is the second parameter */
Entity_Id gnat_size_type
= Etype (Next_Formal (First_Formal (gnat_proc)));
tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
tree gnu_proc = gnat_to_gnu (gnat_proc);
tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
tree gnu_args = NULL_TREE;
tree gnu_call;
/* The first arg is the address of the object, for a
deallocator, then the size */
if (gnu_obj)
gnu_args
= chainon (gnu_args, build_tree_list (NULL_TREE, gnu_obj));
gnu_args
= chainon (gnu_args,
build_tree_list (NULL_TREE,
convert (gnu_size_type, gnu_size)));
gnu_call = build3 (CALL_EXPR, TREE_TYPE (TREE_TYPE (gnu_proc)),
gnu_proc_addr, gnu_args, NULL_TREE);
TREE_SIDE_EFFECTS (gnu_call) = 1;
return gnu_call;
}
}
else if (gnu_obj)
return build_call_1_expr (free_decl, gnu_obj);
/* ??? For now, disable variable-sized allocators in the stack since
we can't yet gimplify an ALLOCATE_EXPR. */
else if (gnat_pool == -1
&& TREE_CODE (gnu_size) == INTEGER_CST && !flag_stack_check)
{
/* If the size is a constant, we can put it in the fixed portion of
the stack frame to avoid the need to adjust the stack pointer. */
if (TREE_CODE (gnu_size) == INTEGER_CST && !flag_stack_check)
{
tree gnu_range
= build_range_type (NULL_TREE, size_one_node, gnu_size);
tree gnu_array_type = build_array_type (char_type_node, gnu_range);
tree gnu_decl
= create_var_decl (get_identifier ("RETVAL"), NULL_TREE,
gnu_array_type, NULL_TREE, false, false, false,
false, NULL, gnat_node);
return convert (ptr_void_type_node,
build_unary_op (ADDR_EXPR, NULL_TREE, gnu_decl));
}
else
gcc_unreachable ();
#if 0
return build2 (ALLOCATE_EXPR, ptr_void_type_node, gnu_size, gnu_align);
#endif
}
else
{
if (Nkind (gnat_node) != N_Allocator || !Comes_From_Source (gnat_node))
Check_No_Implicit_Heap_Alloc (gnat_node);
return build_call_1_expr (malloc_decl, gnu_size);
}
}
/* Build a GCC tree to correspond to allocating an object of TYPE whose
initial value is INIT, if INIT is nonzero. Convert the expression to
RESULT_TYPE, which must be some type of pointer. Return the tree.
GNAT_PROC and GNAT_POOL optionally give the procedure to call and
the storage pool to use. GNAT_NODE is used to provide an error
location for restriction violations messages. If IGNORE_INIT_TYPE is
true, ignore the type of INIT for the purpose of determining the size;
this will cause the maximum size to be allocated if TYPE is of
self-referential size. */
tree
build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
{
tree size = TYPE_SIZE_UNIT (type);
tree result;
/* If the initializer, if present, is a NULL_EXPR, just return a new one. */
if (init && TREE_CODE (init) == NULL_EXPR)
return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
/* 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))
{
tree storage_type
= build_unc_object_type_from_ptr (result_type, type,
get_identifier ("ALLOC"));
tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
tree storage_ptr_type = build_pointer_type (storage_type);
tree storage;
tree template_cons = NULL_TREE;
size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
init);
/* If the size overflows, pass -1 so the allocator will raise
storage error. */
if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
size = ssize_int (-1);
storage = build_call_alloc_dealloc (NULL_TREE, size,
TYPE_ALIGN (storage_type),
gnat_proc, gnat_pool, gnat_node);
storage = convert (storage_ptr_type, protect_multiple_eval (storage));
if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
{
type = TREE_TYPE (TYPE_FIELDS (type));
if (init)
init = convert (type, init);
}
/* If there is an initializing expression, make a constructor for
the entire object including the bounds and copy it into the
object. If there is no initializing expression, just set the
bounds. */
if (init)
{
template_cons = tree_cons (TREE_CHAIN (TYPE_FIELDS (storage_type)),
init, NULL_TREE);
template_cons = tree_cons (TYPE_FIELDS (storage_type),
build_template (template_type, type,
init),
template_cons);
return convert
(result_type,
build2 (COMPOUND_EXPR, storage_ptr_type,
build_binary_op
(MODIFY_EXPR, storage_type,
build_unary_op (INDIRECT_REF, NULL_TREE,
convert (storage_ptr_type, storage)),
gnat_build_constructor (storage_type, template_cons)),
convert (storage_ptr_type, storage)));
}
else
return build2
(COMPOUND_EXPR, result_type,
build_binary_op
(MODIFY_EXPR, template_type,
build_component_ref
(build_unary_op (INDIRECT_REF, NULL_TREE,
convert (storage_ptr_type, storage)),
NULL_TREE, TYPE_FIELDS (storage_type), 0),
build_template (template_type, type, NULL_TREE)),
convert (result_type, convert (storage_ptr_type, storage)));
}
/* If we have an initializing expression, see if its size is simpler
than the size from the type. */
if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
&& (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
|| CONTAINS_PLACEHOLDER_P (size)))
size = TYPE_SIZE_UNIT (TREE_TYPE (init));
/* If the size is still self-referential, reference the initializing
expression, if it is present. If not, this must have been a
call to allocate a library-level object, in which case we use
the maximum size. */
if (CONTAINS_PLACEHOLDER_P (size))
{
if (!ignore_init_type && init)
size = substitute_placeholder_in_expr (size, init);
else
size = max_size (size, true);
}
/* If the size overflows, pass -1 so the allocator will raise
storage error. */
if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
size = ssize_int (-1);
/* If this is a type whose alignment is larger than the
biggest we support in normal alignment and this is in
the default storage pool, make an "aligning type", allocate
it, point to the field we need, and return that. */
if (TYPE_ALIGN (type) > BIGGEST_ALIGNMENT
&& No (gnat_proc))
{
tree new_type = make_aligning_type (type, TYPE_ALIGN (type), size);
result = build_call_alloc_dealloc (NULL_TREE, TYPE_SIZE_UNIT (new_type),
BIGGEST_ALIGNMENT, Empty,
Empty, gnat_node);
result = save_expr (result);
result = convert (build_pointer_type (new_type), result);
result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
result = build_component_ref (result, NULL_TREE,
TYPE_FIELDS (new_type), 0);
result = convert (result_type,
build_unary_op (ADDR_EXPR, NULL_TREE, result));
}
else
result = convert (result_type,
build_call_alloc_dealloc (NULL_TREE, size,
TYPE_ALIGN (type),
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 (init)
{
result = save_expr (result);
result
= build2 (COMPOUND_EXPR, TREE_TYPE (result),
build_binary_op
(MODIFY_EXPR, NULL_TREE,
build_unary_op (INDIRECT_REF,
TREE_TYPE (TREE_TYPE (result)), result),
init),
result);
}
return convert (result_type, result);
}
/* Fill in a VMS descriptor for EXPR and return a constructor for it.
GNAT_FORMAL is how we find the descriptor record. */
tree
fill_vms_descriptor (tree expr, Entity_Id gnat_formal)
{
tree record_type = TREE_TYPE (TREE_TYPE (get_gnu_tree (gnat_formal)));
tree field;
tree const_list = NULL_TREE;
expr = maybe_unconstrained_array (expr);
gnat_mark_addressable (expr);
for (field = TYPE_FIELDS (record_type); field; field = TREE_CHAIN (field))
const_list
= tree_cons (field,
convert (TREE_TYPE (field),
SUBSTITUTE_PLACEHOLDER_IN_EXPR
(DECL_INITIAL (field), expr)),
const_list);
return gnat_build_constructor (record_type, nreverse (const_list));
}
/* Indicate that we need to make the address of EXPR_NODE and it therefore
should not be allocated in a register. Returns true if successful. */
bool
gnat_mark_addressable (tree expr_node)
{
while (1)
switch (TREE_CODE (expr_node))
{
case ADDR_EXPR:
case COMPONENT_REF:
case ARRAY_REF:
case ARRAY_RANGE_REF:
case REALPART_EXPR:
case IMAGPART_EXPR:
case VIEW_CONVERT_EXPR:
case CONVERT_EXPR:
case NON_LVALUE_EXPR:
case NOP_EXPR:
expr_node = TREE_OPERAND (expr_node, 0);
break;
case CONSTRUCTOR:
TREE_ADDRESSABLE (expr_node) = 1;
return true;
case VAR_DECL:
case PARM_DECL:
case RESULT_DECL:
TREE_ADDRESSABLE (expr_node) = 1;
return true;
case FUNCTION_DECL:
TREE_ADDRESSABLE (expr_node) = 1;
return true;
case CONST_DECL:
return (DECL_CONST_CORRESPONDING_VAR (expr_node)
&& (gnat_mark_addressable
(DECL_CONST_CORRESPONDING_VAR (expr_node))));
default:
return true;
}
}
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