This is the mail archive of the
binutils@sourceware.org
mailing list for the binutils project.
Delete redundant struct cie field
- From: Alan Modra <amodra at gmail dot com>
- To: binutils at sourceware dot org
- Date: Fri, 22 Aug 2014 10:13:40 +0930
- Subject: Delete redundant struct cie field
- Authentication-results: sourceware.org; auth=none
cie->output_sec is used to when merging CIEs to ensure that only CIEs
from the same output section are merged. I noticed an assignment to
this field in _bfd_elf_parse_eh_frame, and thought "That's wrong,
output_section isn't set properly when _bfd_elf_parse_eh_frame is
called from gc-sections code". It turns out that this assignment is
premature, and in fact a dead store. find_merged_cie overwrites with
the correct value before the field is ever used. On looking a little
more it becomes apparent that cie->cie_inf.u.cie.u.sec->output_section
holds the same value, so cie->output_sec is redundant.
* elf-eh-frame.c (struct cie): Delete "output_sec" field.
(cie_eq, cie_compute_hash): Use output_section from cie_inf instead.
diff --git a/bfd/elf-eh-frame.c b/bfd/elf-eh-frame.c
index 7783b08..d56440c 100644
--- a/bfd/elf-eh-frame.c
+++ b/bfd/elf-eh-frame.c
@@ -46,7 +46,6 @@ struct cie
} sym;
unsigned int reloc_index;
} personality;
- asection *output_sec;
struct eh_cie_fde *cie_inf;
unsigned char per_encoding;
unsigned char lsda_encoding;
@@ -232,7 +231,8 @@ cie_eq (const void *e1, const void *e2)
&& c1->augmentation_size == c2->augmentation_size
&& memcmp (&c1->personality, &c2->personality,
sizeof (c1->personality)) == 0
- && c1->output_sec == c2->output_sec
+ && (c1->cie_inf->u.cie.u.sec->output_section
+ == c2->cie_inf->u.cie.u.sec->output_section)
&& c1->per_encoding == c2->per_encoding
&& c1->lsda_encoding == c2->lsda_encoding
&& c1->fde_encoding == c2->fde_encoding
@@ -266,7 +266,7 @@ cie_compute_hash (struct cie *c)
h = iterative_hash_object (c->ra_column, h);
h = iterative_hash_object (c->augmentation_size, h);
h = iterative_hash_object (c->personality, h);
- h = iterative_hash_object (c->output_sec, h);
+ h = iterative_hash_object (c->cie_inf->u.cie.u.sec->output_section, h);
h = iterative_hash_object (c->per_encoding, h);
h = iterative_hash_object (c->lsda_encoding, h);
h = iterative_hash_object (c->fde_encoding, h);
@@ -625,7 +625,6 @@ _bfd_elf_parse_eh_frame (bfd *abfd, struct bfd_link_info *info,
cie->cie_inf = this_inf;
cie->length = hdr_length;
- cie->output_sec = sec->output_section;
start = buf;
REQUIRE (read_byte (&buf, end, &cie->version));
@@ -1072,7 +1071,6 @@ find_merged_cie (bfd *abfd, struct bfd_link_info *info, asection *sec,
}
/* See if we can merge this CIE with an earlier one. */
- cie->output_sec = sec->output_section;
cie_compute_hash (cie);
if (hdr_info->cies == NULL)
{
--
Alan Modra
Australia Development Lab, IBM