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authorIan Lance Taylor <iant@google.com>2008-02-14 02:40:15 +0000
committerIan Lance Taylor <iant@google.com>2008-02-14 02:40:15 +0000
commit935e887746227322222835cd002ec486f9f31402 (patch)
treeae527a59653cb6ab116f495c056ad97686ed69f9 /gold/ehframe.cc
parentfd247bfe68f03688b12c8583933f5471f1ed0a86 (diff)
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Align FDE and CIE lengths as needed.
Diffstat (limited to 'gold/ehframe.cc')
-rw-r--r--gold/ehframe.cc58
1 files changed, 43 insertions, 15 deletions
diff --git a/gold/ehframe.cc b/gold/ehframe.cc
index 80fd859..8306f51 100644
--- a/gold/ehframe.cc
+++ b/gold/ehframe.cc
@@ -336,21 +336,28 @@ Eh_frame_hdr::get_fde_addresses(Output_file* of,
// Write the FDE to OVIEW starting at OFFSET. CIE_OFFSET is the
// offset of the CIE in OVIEW. FDE_ENCODING is the encoding, from the
-// CIE. Record the FDE pc for EH_FRAME_HDR. Return the new offset.
+// CIE. ADDRALIGN is the required alignment. Record the FDE pc for
+// EH_FRAME_HDR. Return the new offset.
template<int size, bool big_endian>
section_offset_type
Fde::write(unsigned char* oview, section_offset_type offset,
- section_offset_type cie_offset, unsigned char fde_encoding,
- Eh_frame_hdr* eh_frame_hdr)
+ unsigned int addralign, section_offset_type cie_offset,
+ unsigned char fde_encoding, Eh_frame_hdr* eh_frame_hdr)
{
+ gold_assert((offset & (addralign - 1)) == 0);
+
size_t length = this->contents_.length();
+ // We add 8 when getting the aligned length to account for the
+ // length word and the CIE offset.
+ size_t aligned_full_length = align_address(length + 8, addralign);
+
// Write the length of the FDE as a 32-bit word. The length word
// does not include the four bytes of the length word itself, but it
// does include the offset to the CIE.
elfcpp::Swap<32, big_endian>::writeval(oview + offset,
- length + 4);
+ aligned_full_length - 4);
// Write the offset to the CIE as a 32-bit word. This is the
// difference between the address of the offset word itself and the
@@ -363,11 +370,14 @@ Fde::write(unsigned char* oview, section_offset_type offset,
// will later be applied to the FDE data.
memcpy(oview + offset + 8, this->contents_.data(), length);
+ if (aligned_full_length > length + 8)
+ memset(oview + offset + length + 8, 0, aligned_full_length - (length + 8));
+
// Tell the exception frame header about this FDE.
if (eh_frame_hdr != NULL)
eh_frame_hdr->record_fde(offset, fde_encoding);
- return offset + length + 8;
+ return offset + aligned_full_length;
}
// Class Cie.
@@ -390,13 +400,15 @@ Cie::set_output_offset(section_offset_type output_offset,
Merge_map* merge_map)
{
size_t length = this->contents_.length();
- gold_assert((length & (addralign - 1)) == 0);
+
// Add 4 for length and 4 for zero CIE identifier tag.
length += 8;
merge_map->add_mapping(this->object_, this->shndx_, this->input_offset_,
length, output_offset);
+ length = align_address(length, addralign);
+
for (std::vector<Fde*>::const_iterator p = this->fdes_.begin();
p != this->fdes_.end();
++p)
@@ -404,7 +416,7 @@ Cie::set_output_offset(section_offset_type output_offset,
(*p)->add_mapping(output_offset + length, merge_map);
size_t fde_length = (*p)->length();
- gold_assert((fde_length & (addralign - 1)) == 0);
+ fde_length = align_address(fde_length, addralign);
length += fde_length;
}
@@ -412,35 +424,48 @@ Cie::set_output_offset(section_offset_type output_offset,
}
// Write the CIE to OVIEW starting at OFFSET. EH_FRAME_HDR is for FDE
-// recording. Return the new offset.
+// recording. Round up the bytes to ADDRALIGN. Return the new
+// offset.
template<int size, bool big_endian>
section_offset_type
Cie::write(unsigned char* oview, section_offset_type offset,
- Eh_frame_hdr* eh_frame_hdr)
+ unsigned int addralign, Eh_frame_hdr* eh_frame_hdr)
{
+ gold_assert((offset & (addralign - 1)) == 0);
+
section_offset_type cie_offset = offset;
size_t length = this->contents_.length();
+ // We add 8 when getting the aligned length to account for the
+ // length word and the CIE tag.
+ size_t aligned_full_length = align_address(length + 8, addralign);
+
// Write the length of the CIE as a 32-bit word. The length word
// does not include the four bytes of the length word itself.
- elfcpp::Swap<32, big_endian>::writeval(oview + offset, length + 4);
+ elfcpp::Swap<32, big_endian>::writeval(oview + offset,
+ aligned_full_length - 4);
// Write the tag which marks this as a CIE: a 32-bit zero.
elfcpp::Swap<32, big_endian>::writeval(oview + offset + 4, 0);
// Write out the CIE data.
memcpy(oview + offset + 8, this->contents_.data(), length);
- offset += length + 8;
+
+ if (aligned_full_length > length + 8)
+ memset(oview + offset + length + 8, 0, aligned_full_length - (length + 8));
+
+ offset += aligned_full_length;
// Write out the associated FDEs.
unsigned char fde_encoding = this->fde_encoding_;
for (std::vector<Fde*>::const_iterator p = this->fdes_.begin();
p != this->fdes_.end();
++p)
- offset = (*p)->write<size, big_endian>(oview, offset, cie_offset,
- fde_encoding, eh_frame_hdr);
+ offset = (*p)->write<size, big_endian>(oview, offset, addralign,
+ cie_offset, fde_encoding,
+ eh_frame_hdr);
return offset;
}
@@ -1100,16 +1125,19 @@ template<int size, bool big_endian>
void
Eh_frame::do_sized_write(unsigned char* oview)
{
+ unsigned int addralign = this->addralign();
section_offset_type o = 0;
for (Unmergeable_cie_offsets::iterator p =
this->unmergeable_cie_offsets_.begin();
p != this->unmergeable_cie_offsets_.end();
++p)
- o = (*p)->write<size, big_endian>(oview, o, this->eh_frame_hdr_);
+ o = (*p)->write<size, big_endian>(oview, o, addralign,
+ this->eh_frame_hdr_);
for (Cie_offsets::iterator p = this->cie_offsets_.begin();
p != this->cie_offsets_.end();
++p)
- o = (*p)->write<size, big_endian>(oview, o, this->eh_frame_hdr_);
+ o = (*p)->write<size, big_endian>(oview, o, addralign,
+ this->eh_frame_hdr_);
}
#ifdef HAVE_TARGET_32_LITTLE