ld: Add fold_segment_align/fold_segment_relro_end/fold_segment_end

Extract DATA_SEGMENT_END/DATA_SEGMENT_ALIGN/DATA_SEGMENT_RELRO_END cases
for GNU_RELRO segment into separate functions so that they can also be
used for text-only LOAD segment.

	* ldexp.c (fold_unary): Extract the DATA_SEGMENT_END case to ...
	(fold_segment_end): New function.
	(fold_binary): Extract the DATA_SEGMENT_ALIGN case to ...
	(fold_segment_align): New function.
	(fold_binary): Extract the DATA_SEGMENT_RELRO_END case to ...
	(fold_segment_relro_end): New function.
This commit is contained in:
H.J. Lu 2017-11-12 17:20:09 -08:00
parent 0f99513f2a
commit d7475e036f
2 changed files with 114 additions and 89 deletions

View File

@ -1,3 +1,12 @@
2017-11-12 H.J. Lu <hongjiu.lu@intel.com>
* ldexp.c (fold_unary): Extract the DATA_SEGMENT_END case to ...
(fold_segment_end): New function.
(fold_binary): Extract the DATA_SEGMENT_ALIGN case to ...
(fold_segment_align): New function.
(fold_binary): Extract the DATA_SEGMENT_RELRO_END case to ...
(fold_segment_relro_end): New function.
2017-11-12 H.J. Lu <hongjiu.lu@intel.com>
* ldexp.h (phase_enum): Rename exp_dataseg_none,

View File

@ -342,6 +342,30 @@ update_definedness (const char *name, struct bfd_link_hash_entry *h)
return ret;
}
static void
fold_segment_end (seg_align_type *seg)
{
if (expld.phase == lang_first_phase_enum
|| expld.section != bfd_abs_section_ptr)
{
expld.result.valid_p = FALSE;
}
else if (seg->phase == exp_seg_align_seen
|| seg->phase == exp_seg_relro_seen)
{
seg->phase = exp_seg_end_seen;
seg->end = expld.result.value;
}
else if (seg->phase == exp_seg_done
|| seg->phase == exp_seg_adjust
|| seg->phase == exp_seg_relro_adjust)
{
/* OK. */
}
else
expld.result.valid_p = FALSE;
}
static void
fold_unary (etree_type *tree)
{
@ -389,25 +413,7 @@ fold_unary (etree_type *tree)
break;
case DATA_SEGMENT_END:
if (expld.phase == lang_first_phase_enum
|| expld.section != bfd_abs_section_ptr)
{
expld.result.valid_p = FALSE;
}
else if (expld.dataseg.phase == exp_seg_align_seen
|| expld.dataseg.phase == exp_seg_relro_seen)
{
expld.dataseg.phase = exp_seg_end_seen;
expld.dataseg.end = expld.result.value;
}
else if (expld.dataseg.phase == exp_seg_done
|| expld.dataseg.phase == exp_seg_adjust
|| expld.dataseg.phase == exp_seg_relro_adjust)
{
/* OK. */
}
else
expld.result.valid_p = FALSE;
fold_segment_end (&expld.dataseg);
break;
default:
@ -443,6 +449,84 @@ arith_result_section (const etree_value_type *lhs)
}
}
static void
fold_segment_align (seg_align_type *seg, etree_value_type *lhs)
{
seg->relro = exp_seg_relro_start;
if (expld.phase == lang_first_phase_enum
|| expld.section != bfd_abs_section_ptr)
expld.result.valid_p = FALSE;
else
{
bfd_vma maxpage = lhs->value;
bfd_vma commonpage = expld.result.value;
expld.result.value = align_n (expld.dot, maxpage);
if (seg->phase == exp_seg_relro_adjust)
expld.result.value = seg->base;
else if (seg->phase == exp_seg_adjust)
{
if (commonpage < maxpage)
expld.result.value += ((expld.dot + commonpage - 1)
& (maxpage - commonpage));
}
else
{
expld.result.value += expld.dot & (maxpage - 1);
if (seg->phase == exp_seg_done)
{
/* OK. */
}
else if (seg->phase == exp_seg_none)
{
seg->phase = exp_seg_align_seen;
seg->base = expld.result.value;
seg->pagesize = commonpage;
seg->maxpagesize = maxpage;
seg->relro_end = 0;
}
else
expld.result.valid_p = FALSE;
}
}
}
static void
fold_segment_relro_end (seg_align_type *seg, etree_value_type *lhs)
{
/* Operands swapped! XXX_SEGMENT_RELRO_END(offset,exp) has offset
in expld.result and exp in lhs. */
seg->relro = exp_seg_relro_end;
seg->relro_offset = expld.result.value;
if (expld.phase == lang_first_phase_enum
|| expld.section != bfd_abs_section_ptr)
expld.result.valid_p = FALSE;
else if (seg->phase == exp_seg_align_seen
|| seg->phase == exp_seg_adjust
|| seg->phase == exp_seg_relro_adjust
|| seg->phase == exp_seg_done)
{
if (seg->phase == exp_seg_align_seen
|| seg->phase == exp_seg_relro_adjust)
seg->relro_end = lhs->value + expld.result.value;
if (seg->phase == exp_seg_relro_adjust
&& (seg->relro_end & (seg->pagesize - 1)))
{
seg->relro_end += seg->pagesize - 1;
seg->relro_end &= ~(seg->pagesize - 1);
expld.result.value = seg->relro_end - expld.result.value;
}
else
expld.result.value = lhs->value;
if (seg->phase == exp_seg_align_seen)
seg->phase = exp_seg_relro_seen;
}
else
expld.result.valid_p = FALSE;
}
static void
fold_binary (etree_type *tree)
{
@ -573,79 +657,11 @@ fold_binary (etree_type *tree)
break;
case DATA_SEGMENT_ALIGN:
expld.dataseg.relro = exp_seg_relro_start;
if (expld.phase == lang_first_phase_enum
|| expld.section != bfd_abs_section_ptr)
expld.result.valid_p = FALSE;
else
{
bfd_vma maxpage = lhs.value;
bfd_vma commonpage = expld.result.value;
expld.result.value = align_n (expld.dot, maxpage);
if (expld.dataseg.phase == exp_seg_relro_adjust)
expld.result.value = expld.dataseg.base;
else if (expld.dataseg.phase == exp_seg_adjust)
{
if (commonpage < maxpage)
expld.result.value += ((expld.dot + commonpage - 1)
& (maxpage - commonpage));
}
else
{
expld.result.value += expld.dot & (maxpage - 1);
if (expld.dataseg.phase == exp_seg_done)
{
/* OK. */
}
else if (expld.dataseg.phase == exp_seg_none)
{
expld.dataseg.phase = exp_seg_align_seen;
expld.dataseg.base = expld.result.value;
expld.dataseg.pagesize = commonpage;
expld.dataseg.maxpagesize = maxpage;
expld.dataseg.relro_end = 0;
}
else
expld.result.valid_p = FALSE;
}
}
fold_segment_align (&expld.dataseg, &lhs);
break;
case DATA_SEGMENT_RELRO_END:
/* Operands swapped! DATA_SEGMENT_RELRO_END(offset,exp)
has offset in expld.result and exp in lhs. */
expld.dataseg.relro = exp_seg_relro_end;
expld.dataseg.relro_offset = expld.result.value;
if (expld.phase == lang_first_phase_enum
|| expld.section != bfd_abs_section_ptr)
expld.result.valid_p = FALSE;
else if (expld.dataseg.phase == exp_seg_align_seen
|| expld.dataseg.phase == exp_seg_adjust
|| expld.dataseg.phase == exp_seg_relro_adjust
|| expld.dataseg.phase == exp_seg_done)
{
if (expld.dataseg.phase == exp_seg_align_seen
|| expld.dataseg.phase == exp_seg_relro_adjust)
expld.dataseg.relro_end = lhs.value + expld.result.value;
if (expld.dataseg.phase == exp_seg_relro_adjust
&& (expld.dataseg.relro_end
& (expld.dataseg.pagesize - 1)))
{
expld.dataseg.relro_end += expld.dataseg.pagesize - 1;
expld.dataseg.relro_end &= ~(expld.dataseg.pagesize - 1);
expld.result.value = (expld.dataseg.relro_end
- expld.result.value);
}
else
expld.result.value = lhs.value;
if (expld.dataseg.phase == exp_seg_align_seen)
expld.dataseg.phase = exp_seg_relro_seen;
}
else
expld.result.valid_p = FALSE;
fold_segment_relro_end (&expld.dataseg, &lhs);
break;
default: