OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

re PR middle-end/22043 (Fields not initialized for automatic structs with flexible array members)

Browse Source 
PR tree-optimization/22043
	* tree.h (count_type_elements): Add ALLOW_FLEXARR argument.
	* expr.c (count_type_elements): Add ALLOW_FLEXARR argument.
	If ALLOW_FLEXARR, handle types ending with flexible array member.
	Pass false as second argument to recursive count_type_elements calls.
	(categorize_ctor_elements_1, mostly_zeros_p): Pass false as second
	argument to count_type_elements call.
	* tree-sra.c (decide_block_copy): Likewise.
	* gimplify.c (gimplify_init_constructor): If num_type_elements < 0
	for a constant-sized object, set cleared as well.  Pass true as
	second argument to count_type_elements call.

	* gcc.c-torture/execute/20050613-1.c: New test.

From-SVN: r103389
This commit is contained in:
Jakub Jelinek 2005-08-23 09:28:26 +02:00 committed by Jakub Jelinek
parent 18b10a7276
commit 73ed17ff80
7 changed files with 80 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
gcc/ChangeLog
View File

@ -1,3 +1,17 @@
2005-08-23 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/22043
* tree.h (count_type_elements): Add ALLOW_FLEXARR argument.
* expr.c (count_type_elements): Add ALLOW_FLEXARR argument.
If ALLOW_FLEXARR, handle types ending with flexible array member.
Pass false as second argument to recursive count_type_elements calls.
(categorize_ctor_elements_1, mostly_zeros_p): Pass false as second
argument to count_type_elements call.
* tree-sra.c (decide_block_copy): Likewise.
* gimplify.c (gimplify_init_constructor): If num_type_elements < 0
for a constant-sized object, set cleared as well. Pass true as
second argument to count_type_elements call.
2005-08-23 Alan Modra <amodra@bigpond.net.au>
PR target/21571

29
gcc/expr.c
View File

@ -4504,7 +4504,7 @@ categorize_ctor_elements_1 (tree ctor, HOST_WIDE_INT *p_nz_elts,
/* And now we have to find out if the element itself is fully
constructed. E.g. for union { struct { int a, b; } s; } u
= { .s = { .a = 1 } }. */
if (elt_count == count_type_elements (init_sub_type))
if (elt_count == count_type_elements (init_sub_type, false))
clear_this = false;
}
}
@ -4532,10 +4532,11 @@ categorize_ctor_elements (tree ctor, HOST_WIDE_INT *p_nz_elts,
}
/* Count the number of scalars in TYPE. Return -1 on overflow or
variable-sized. */
variable-sized. If ALLOW_FLEXARR is true, don't count flexible
array member at the end of the structure. */
HOST_WIDE_INT
count_type_elements (tree type)
count_type_elements (tree type, bool allow_flexarr)
{
const HOST_WIDE_INT max = ~((HOST_WIDE_INT)1 << (HOST_BITS_PER_WIDE_INT-1));
switch (TREE_CODE (type))
@ -4546,7 +4547,7 @@ count_type_elements (tree type)
if (telts && host_integerp (telts, 1))
{
HOST_WIDE_INT n = tree_low_cst (telts, 1) + 1;
HOST_WIDE_INT m = count_type_elements (TREE_TYPE (type));
HOST_WIDE_INT m = count_type_elements (TREE_TYPE (type), false);
if (n == 0)
return 0;
else if (max / n > m)
@ -4563,9 +4564,23 @@ count_type_elements (tree type)
for (f = TYPE_FIELDS (type); f ; f = TREE_CHAIN (f))
if (TREE_CODE (f) == FIELD_DECL)
{
t = count_type_elements (TREE_TYPE (f));
t = count_type_elements (TREE_TYPE (f), false);
if (t < 0)
return -1;
{
/* Check for structures with flexible array member. */
tree tf = TREE_TYPE (f);
if (allow_flexarr
&& TREE_CHAIN (f) == NULL
&& TREE_CODE (tf) == ARRAY_TYPE
&& TYPE_DOMAIN (tf)
&& TYPE_MIN_VALUE (TYPE_DOMAIN (tf))
&& integer_zerop (TYPE_MIN_VALUE (TYPE_DOMAIN (tf)))
&& !TYPE_MAX_VALUE (TYPE_DOMAIN (tf))
&& int_size_in_bytes (type) >= 0)
break;
return -1;
}
n += t;
}
@ -4623,7 +4638,7 @@ mostly_zeros_p (tree exp)
if (must_clear)
return 1;
elts = count_type_elements (TREE_TYPE (exp));
elts = count_type_elements (TREE_TYPE (exp), false);
return nz_elts < elts / 4;
}

15
gcc/gimplify.c
View File

@ -2706,13 +2706,18 @@ gimplify_init_constructor (tree *expr_p, tree *pre_p,
parts in, then generate code for the non-constant parts. */
/* TODO. There's code in cp/typeck.c to do this. */
num_type_elements = count_type_elements (TREE_TYPE (ctor));
num_type_elements = count_type_elements (type, true);
/* If there are "lots" of zeros, then block clear the object first. */
if (num_type_elements - num_nonzero_elements > CLEAR_RATIO
&& num_nonzero_elements < num_type_elements/4)
/* If count_type_elements could not determine number of type elements
for a constant-sized object, assume clearing is needed.
Don't do this for variable-sized objects, as store_constructor
will ignore the clearing of variable-sized objects. */
if (num_type_elements < 0 && int_size_in_bytes (type) >= 0)
cleared = true;
/* If there are "lots" of zeros, then block clear the object first. */
else if (num_type_elements - num_nonzero_elements > CLEAR_RATIO
&& num_nonzero_elements < num_type_elements/4)
cleared = true;
/* ??? This bit ought not be needed. For any element not present
in the initializer, we should simply set them to zero. Except
we'd need to *find* the elements that are not present, and that

5
gcc/testsuite/ChangeLog
View File

@ -1,3 +1,8 @@
2005-08-23 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/22043
* gcc.c-torture/execute/20050613-1.c: New test.
2005-08-23 Ben Elliston <bje@au.ibm.com>
* gcc.c-torture/execute/ieee/ieee.exp: Load gcc-dg.exp library.

27
gcc/testsuite/gcc.c-torture/execute/20050613-1.c Normal file
View File

@ -0,0 +1,27 @@
/* PR tree-optimization/22043 */
extern void abort (void);
struct A { int i; int j; int k; int l; };
struct B { struct A a; int r[1]; };
struct C { struct A a; int r[0]; };
struct D { struct A a; int r[]; };
void
foo (struct A *x)
{
if (x->i != 0 || x->j != 5 || x->k != 0 || x->l != 0)
abort ();
}
int
main ()
{
struct B b = { .a.j = 5 };
struct C c = { .a.j = 5 };
struct D d = { .a.j = 5 };
foo (&b.a);
foo (&c.a);
foo (&d.a);
return 0;
}

2
gcc/tree-sra.c
View File

@ -1338,7 +1338,7 @@ decide_block_copy (struct sra_elt *elt)
: MOVE_RATIO;
full_size = tree_low_cst (size_tree, 1);
full_count = count_type_elements (elt->type);
full_count = count_type_elements (elt->type, false);
inst_count = sum_instantiated_sizes (elt, &inst_size);
/* ??? What to do here. If there are two fields, and we've only

2
gcc/tree.h
View File

@ -3555,7 +3555,7 @@ extern bool initializer_zerop (tree);
extern void categorize_ctor_elements (tree, HOST_WIDE_INT *, HOST_WIDE_INT *,
HOST_WIDE_INT *, bool *);
extern HOST_WIDE_INT count_type_elements (tree);
extern HOST_WIDE_INT count_type_elements (tree, bool);
/* add_var_to_bind_expr (bind_expr, var) binds var to bind_expr. */