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varasm.c (align_variable): New function.

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* varasm.c (align_variable): New function.
	(get_block_for_decl): Apply align_variable to DECL before
	calculating section information.
	(assemble_variable): Split out alignment computation.

From-SVN: r113250
This commit is contained in:
David Edelsohn 2006-04-25 15:00:53 +00:00 committed by David Edelsohn
parent 495db1a115
commit d5fa3ec8dc
2 changed files with 54 additions and 37 deletions
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7
gcc/ChangeLog
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@ -1,3 +1,10 @@
2006-04-25 David Edelsohn <edelsohn@gnu.org>
* varasm.c (align_variable): New function.
(get_block_for_decl): Apply align_variable to DECL before
calculating section information.
(assemble_variable): Split out alignment computation.
2006-04-25 Andreas Krebbel <krebbel1@de.ibm.com>
* expmed.c (store_bit_field): Handle paradoxical subregs on big endian

84
gcc/varasm.c
View File

@ -828,6 +828,48 @@ bss_initializer_p (tree decl)
&& initializer_zerop (DECL_INITIAL (decl))));
}
/* Compute the alignment of variable specified by DECL.
DONT_OUTPUT_DATA is from assemble_variable. */
static void
align_variable (tree decl, bool dont_output_data)
{
unsigned int align = DECL_ALIGN (decl);
/* In the case for initialing an array whose length isn't specified,
where we have not yet been able to do the layout,
figure out the proper alignment now. */
if (dont_output_data && DECL_SIZE (decl) == 0
&& TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
/* Some object file formats have a maximum alignment which they support.
In particular, a.out format supports a maximum alignment of 4. */
if (align > MAX_OFILE_ALIGNMENT)
{
warning (0, "alignment of %q+D is greater than maximum object "
"file alignment. Using %d", decl,
MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
align = MAX_OFILE_ALIGNMENT;
}
/* On some machines, it is good to increase alignment sometimes. */
if (! DECL_USER_ALIGN (decl))
{
#ifdef DATA_ALIGNMENT
align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
#endif
#ifdef CONSTANT_ALIGNMENT
if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
#endif
}
/* Reset the alignment in case we have made it tighter, so we can benefit
from it in get_pointer_alignment. */
DECL_ALIGN (decl) = align;
}
/* Return the section into which the given VAR_DECL or CONST_DECL
should be placed. PREFER_NOSWITCH_P is true if a noswitch
section should be used wherever possible. */
@ -899,6 +941,8 @@ get_block_for_decl (tree decl)
/* Find out which section should contain DECL. We cannot put it into
an object block if it requires a standalone definition. */
if (TREE_CODE (decl) == VAR_DECL)
align_variable (decl, 0);
sect = get_variable_section (decl, true);
if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
return NULL;
@ -1683,7 +1727,6 @@ assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
int at_end ATTRIBUTE_UNUSED, int dont_output_data)
{
const char *name;
unsigned int align;
rtx decl_rtl, symbol;
section *sect;
@ -1764,41 +1807,8 @@ assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
/* Compute the alignment of this data. */
align = DECL_ALIGN (decl);
/* In the case for initialing an array whose length isn't specified,
where we have not yet been able to do the layout,
figure out the proper alignment now. */
if (dont_output_data && DECL_SIZE (decl) == 0
&& TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
/* Some object file formats have a maximum alignment which they support.
In particular, a.out format supports a maximum alignment of 4. */
if (align > MAX_OFILE_ALIGNMENT)
{
warning (0, "alignment of %q+D is greater than maximum object "
"file alignment. Using %d", decl,
MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
align = MAX_OFILE_ALIGNMENT;
}
/* On some machines, it is good to increase alignment sometimes. */
if (! DECL_USER_ALIGN (decl))
{
#ifdef DATA_ALIGNMENT
align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
#endif
#ifdef CONSTANT_ALIGNMENT
if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
#endif
}
/* Reset the alignment in case we have made it tighter, so we can benefit
from it in get_pointer_alignment. */
DECL_ALIGN (decl) = align;
set_mem_align (decl_rtl, align);
align_variable (decl, dont_output_data);
set_mem_align (decl_rtl, DECL_ALIGN (decl));
if (TREE_PUBLIC (decl))
maybe_assemble_visibility (decl);
@ -1834,7 +1844,7 @@ assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
else
{
switch_to_section (sect);
if (align > BITS_PER_UNIT)
if (DECL_ALIGN (decl) > BITS_PER_UNIT)
ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
assemble_variable_contents (decl, name, dont_output_data);
}